Tetrafluoroethylene-based polymer composition, binder for electrochemical device, electrode mixture, electrode, and secondary battery

Abstract

To provide a tetrafluoroethylene-based polymer composition for a binder for an electrochemical device capable of improving high-temperature cycle characteristics of the electrochemical device and also suppressing gas generation and to provide a binder for the electrochemical device, an electrode composite, an electrode, and a secondary battery, all using the same.SOLUTION: The tetrafluoroethylene polymer composition for use in a binder for an electrochemical device contains a tetrafluoroethylene polymer, which is a copolymer of tetrafluoroethylene and a monomer having a polar group, and has fibrillation ability.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates to a tetrafluoroethylene-based polymer composition, a binder for an electrochemical device, an electrode mixture, an electrode, and a secondary battery. [Background technology]

[0002] Secondary batteries such as lithium-ion secondary batteries have high voltage, high energy density, low self-discharge, little memory effect, and can be made extremely lightweight, and are therefore used in small, portable electrical and electronic devices such as notebook computers, mobile phones, smartphones, tablet computers, and ultrabooks, and are also being put into practical use as a wide range of power sources, including on-board power supplies for driving automobiles and large-scale stationary power supplies. There is a demand for even higher energy densities in secondary batteries, and further improvements in their battery characteristics are also required.

[0003] Patent Document 1 describes an energy storage device in which at least one of the cathode and the anode contains a polytetrafluoroethylene mixed binder material.

[0004] Patent Documents 2 to 6 describe the use of polytetrafluoroethylene as a binder for batteries. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Special Publication No. 2017-517862 [Patent Document 2] International Publication No. 2021 / 181887 [Patent Document 3] International Publication No. 2021 / 181888 [Patent Document 4] International Publication No. 2021 / 192541 [Patent Document 5] International Publication No. 2022 / 138942 [Patent Document 6] International Publication No. 2022 / 138939 Summary of the Invention [Problem to be solved by the invention]

[0006] An object of the present disclosure is to provide a tetrafluoroethylene-based polymer composition for a binder for an electrochemical device that can improve the high-temperature cycle characteristics of an electrochemical device and suppress gas generation, as well as a binder for an electrochemical device, an electrode mixture, an electrode, and a secondary battery that use the same. [Means for solving the problem]

[0007] The present disclosure (1) is a tetrafluoroethylene-based polymer composition used as a binder for electrochemical devices, which contains a tetrafluoroethylene-based polymer that is a copolymer of tetrafluoroethylene and a monomer having a polar group, and has fibrillation ability.

[0008] The present disclosure (2) is the tetrafluoroethylene-based polymer composition according to the present disclosure (1), wherein the monomer having a polar group is at least one selected from the group consisting of a non-fluorinated monomer having a carboxyl group, a non-fluorinated monomer having a sulfo group, a monomer represented by the following formula (10-1), a monomer represented by the following general formula (5), and a monomer represented by the following general formula (6): CH2=CR 11 -CO-OR 13 (10-1) (In the formula, R 11 is a hydrogen atom or an alkyl group, and R 13 is a hydrogen atom or an alkyl group. CX2=CY(-CZ2-O-Rf-Y 3 )(5) (In the formula, X's may be the same or different and each represent -H or -F; Y's may be -H, -F, an alkyl group or a fluorine-containing alkyl group; and Z's may be the same or different and each represent -H, -F, an alkyl group or a fluorine-containing alkyl group. Rf's may be a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and an ether bond. Y 3 is a hydrophilic group. CX2=CY(-O-Rf-Y 3 )(6) (In the formula, X may be the same or different and is -H or -F; Y is -H, -F, an alkyl group or a fluorine-containing alkyl group; and Rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and an ether bond. Y 3 is a hydrophilic group.

[0009] The present disclosure (3) is a powder of the tetrafluoroethylene-based polymer composition according to the present disclosure (1) or (2).

[0010] The present disclosure (4) is a tetrafluoroethylene-based polymer composition according to any one of the present disclosures (1) to (3), which is used as a binder for lithium ion secondary batteries and is in the form of powder.

[0011] The present disclosure (5) is a binder for electrochemical devices consisting essentially of a tetrafluoroethylene-based polymer composition, the tetrafluoroethylene-based polymer composition containing a tetrafluoroethylene-based polymer that is a copolymer of tetrafluoroethylene and a monomer having a polar group, and having fibrillation ability.

[0012] The present disclosure (6) is the binder for electrochemical devices according to the present disclosure (5), wherein the tetrafluoroethylene-based polymer composition has an endothermic peak temperature of 327°C or higher and 350°C or lower.

[0013] The present disclosure (7) is the binder for electrochemical devices according to the present disclosure (5) or (6), wherein the standard specific gravity of the tetrafluoroethylene-based polymer composition is 2.280 or less.

[0014] The present disclosure (8) is the binder for electrochemical devices according to any one of the present disclosures (5) to (7), wherein the 1.0% mass loss temperature of the tetrafluoroethylene polymer composition is 492° C. or lower.

[0015] The present disclosure (9) is the binder for electrochemical devices according to any one of the present disclosures (5) to (8), wherein the tetrafluoroethylene polymer composition has a thermal stability index (TII) of 20 or more.

[0016] The present disclosure (10) is the binder for electrochemical devices according to any one of the present disclosures (5) to (9), wherein the tetrafluoroethylene polymer composition further contains a fluorine-containing compound having a hydrophilic group.

[0017] The present disclosure (11) is a method for manufacturing a compound according to the present invention, wherein the hydrophilic group is -SO3M a , -SO2M a , -OSO2M a , -PO3M a , -COOM a , -OCOM a , and -OM a (In the formula, M a -H, metal atom, -NR 2 4. An optionally substituted imidazolium, an optionally substituted pyridinium, or an optionally substituted phosphonium, wherein R 2 is H or an organic group.) is at least one selected from the group consisting of:

[0018] The present disclosure (12) is the binder for electrochemical devices according to any one of the present disclosures (5) to (11), wherein the tetrafluoroethylene-based polymer composition contains a compound represented by the following general formula (1): General formula (1):(H-(CF2) m-1 -COO)p M 1 (wherein m is 4 to 20. M 1 is H, metal atom, NR 5 4(R 5 may be the same or different and are H or an organic group having 1 to 10 carbon atoms), imidazolium which may have a substituent, pyridinium which may have a substituent, or phosphonium which may have a substituent. p is 1 or 2.

[0019] The present disclosure (13) is the binder for electrochemical devices according to any one of the present disclosures (5) to (12), wherein the tetrafluoroethylene polymer composition contains a compound represented by the following general formula (2): General formula (2):(H-(CF2) n -SO3) q M 2 (wherein n is 4 to 20. M 2 is H, metal atom, NR 5 4(R 5 is the same as above), optionally substituted imidazolium, optionally substituted pyridinium, or optionally substituted phosphonium. q is 1 or 2.

[0020] The present disclosure (14) is the binder for electrochemical devices according to any one of the present disclosures (5) to (13), wherein the tetrafluoroethylene-based polymer composition is substantially free of a compound represented by the following general formula (3): General formula (3): (H-(CF2)8-SO3) q M 2 (In the formula, M 2 is H, metal atom, NR 5 4(R 5 may be the same or different and are H or an organic group having 1 to 10 carbon atoms), imidazolium which may have a substituent, pyridinium which may have a substituent, or phosphonium which may have a substituent. q is 1 or 2.

[0021] The present disclosure (15) is the binder for electrochemical devices according to any one of the present disclosures (5) to (14), wherein the monomer having a polar group is a non-fluorine-containing monomer having a polar group.

[0022] The present disclosure (16) is the binder for electrochemical devices according to any one of the present disclosures (5) to (15), wherein the monomer having a polar group is a monomer represented by the following general formula (10): General formula (10): CH2=CR 11 -L 11 -R 12 (In the formula, R 11 represents a hydrogen atom or an alkyl group. 11 represents a single bond, -CO-O-*, -O-CO-* or -O-. * represents R 12 R represents the bond position with 12 represents a hydrogen atom, an alkyl group, or a nitrile group.

[0023] The present disclosure (17) is the binder for electrochemical devices according to any one of the present disclosures (5) to (15), wherein the monomer having a polar group is at least one selected from the group consisting of a non-fluorinated monomer having a carboxyl group, a non-fluorinated monomer having a sulfo group, a monomer represented by the following formula (10-1), a monomer represented by the following general formula (5), and a monomer represented by the following general formula (6): CH2=CR 11 -CO-OR 13 (10-1) (In the formula, R 11 is a hydrogen atom or an alkyl group, and R 13 is a hydrogen atom or an alkyl group. CX2=CY(-CZ2-O-Rf-Y 3 )(5) (In the formula, X's may be the same or different and each represent -H or -F; Y's may be -H, -F, an alkyl group or a fluorine-containing alkyl group; and Z's may be the same or different and each represent -H, -F, an alkyl group or a fluorine-containing alkyl group. Rf's may be a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and an ether bond. Y 3is a hydrophilic group. CX2=CY(-O-Rf-Y 3 )(6) (In the formula, X may be the same or different and is -H or -F; Y is -H, -F, an alkyl group or a fluorine-containing alkyl group; and Rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and an ether bond. Y 3 is a hydrophilic group.

[0024] The present disclosure (18) is a binder for lithium ion secondary batteries, and is the binder for electrochemical devices according to any one of the present disclosures (5) to (17) in the form of powder.

[0025] The present disclosure (19) is a tetrafluoroethylene-based polymer composition used in a binder for electrochemical devices, the tetrafluoroethylene-based polymer composition comprising a tetrafluoroethylene-based polymer that is a copolymer of tetrafluoroethylene and a monomer having a polar group, having fibrillated portions, and having an endothermic peak temperature of 327°C or higher and 350°C or lower.

[0026] The present disclosure (20) is the tetrafluoroethylene-based polymer composition according to the present disclosure (19), wherein the monomer having a polar group is at least one selected from the group consisting of a non-fluorinated monomer having a carboxyl group, a non-fluorinated monomer having a sulfo group, a monomer represented by the following formula (10-1), a monomer represented by the following general formula (5), and a monomer represented by the following general formula (6): CH2=CR 11 -CO-OR 13 (10-1) (In the formula, R 11 is a hydrogen atom or an alkyl group, and R 13 is a hydrogen atom or an alkyl group. CX2=CY(-CZ2-O-Rf-Y 3 )(5) (In the formula, X's may be the same or different and each represent -H or -F; Y's may be -H, -F, an alkyl group or a fluorine-containing alkyl group; and Z's may be the same or different and each represent -H, -F, an alkyl group or a fluorine-containing alkyl group. Rf's may be a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and an ether bond. Y 3 is a hydrophilic group. CX2=CY(-O-Rf-Y 3 )(6) (In the formula, X may be the same or different and is -H or -F; Y is -H, -F, an alkyl group or a fluorine-containing alkyl group; and Rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and an ether bond. Y 3 is a hydrophilic group.

[0027] The present disclosure (21) is a tetrafluoroethylene-based polymer composition according to the present disclosure (19) or (20) in the form of a sheet, which is used as a binder for lithium-ion secondary batteries.

[0028] The present disclosure (22) is a binder for electrochemical devices consisting essentially of a tetrafluoroethylene-based polymer composition, wherein the tetrafluoroethylene-based polymer composition contains a tetrafluoroethylene-based polymer that is a copolymer of tetrafluoroethylene and a monomer having a polar group, has fibrillated portions, and has an endothermic peak temperature of 327°C or higher and 350°C or lower.

[0029] The present disclosure (23) is the binder for electrochemical devices according to the present disclosure (22), wherein the monomer having a polar group is at least one selected from the group consisting of a non-fluorinated monomer having a carboxyl group, a non-fluorinated monomer having a sulfo group, a monomer represented by the following formula (10-1), a monomer represented by the following general formula (5), and a monomer represented by the following general formula (6): CH2=CR 11 -CO-OR 13 (10-1) (In the formula, R 11is a hydrogen atom or an alkyl group, and R 13 is a hydrogen atom or an alkyl group. CX2=CY(-CZ2-O-Rf-Y 3 )(5) (In the formula, X's may be the same or different and each represent -H or -F; Y's may be -H, -F, an alkyl group or a fluorine-containing alkyl group; and Z's may be the same or different and each represent -H, -F, an alkyl group or a fluorine-containing alkyl group. Rf's may be a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and an ether bond. Y 3 is a hydrophilic group. CX2=CY(-O-Rf-Y 3 )(6) (In the formula, X may be the same or different and is -H or -F; Y is -H, -F, an alkyl group or a fluorine-containing alkyl group; and Rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and an ether bond. Y 3 is a hydrophilic group.

[0030] The present disclosure (24) is a binder for lithium ion secondary batteries, and is the binder for electrochemical devices according to the present disclosure (22) or (23) in the form of a sheet.

[0031] The present disclosure (25) is an electrode mixture comprising the tetrafluoroethylene-based polymer composition according to any one of the present disclosures (1) to (4), (19) to (21), or the binder for electrochemical devices according to any one of the present disclosures (5) to (18), (22) to (24), and an electrode active material.

[0032] The present disclosure (26) is the electrode mixture according to the present disclosure (25) in the form of a sheet.

[0033] The present disclosure (27) is an electrode comprising the tetrafluoroethylene-based polymer composition according to any one of the present disclosures (1) to (4), (19) to (21), or the binder for electrochemical devices according to any one of the present disclosures (5) to (18), (22) to (24), an electrode active material, and a current collector.

[0034] The present disclosure (28) is a secondary battery including the electrode according to the present disclosure (27). [Effects of the Invention]

[0035] According to the present disclosure, it is possible to provide a tetrafluoroethylene-based polymer composition for a binder for an electrochemical device that can improve the high-temperature cycle characteristics of an electrochemical device and suppress gas generation, as well as a binder for an electrochemical device, an electrode mixture, an electrode, and a secondary battery that use the same. DETAILED DESCRIPTION OF THE INVENTION

[0036] In this disclosure, "organic group" means a group containing one or more carbon atoms or a group formed by removing one hydrogen atom from an organic compound. The organic group is preferably an alkyl group which may have one or more substituents.

[0037] The present disclosure will be specifically described below.

[0038] The present disclosure provides a tetrafluoroethylene (TFE)-based polymer composition used as a binder for electrochemical devices, the TFE-based polymer composition containing a TFE-based polymer that is a copolymer of TFE and a monomer having a polar group, and having fibrillation ability (hereinafter also referred to as the TFE-based polymer composition (1) of the present disclosure).

[0039] The TFE-based polymer composition (1) of the present disclosure, when used as a binder for electrochemical devices, can improve the high-temperature cycle characteristics of the electrochemical devices and suppress gas generation, and can also provide a composite sheet with excellent strength and flexibility. The TFE-based polymer composition (1) of the present disclosure can be used in a dry process, which eliminates the need for a large amount of a dispersion medium such as water or an organic solvent, and allows for a wide selection of electrode active materials and solid electrolytes to be combined, which is advantageous in terms of production process, and also reduces the number of steps and costs associated with the use of a dispersion medium. Furthermore, the TFE polymer composition (1) of the present disclosure has excellent binding strength with active materials and electrolytes, so that the amount used can be reduced.

[0040] The TFE-based polymer composition (1) of the present disclosure contains a TFE-based polymer that is a copolymer of TFE and a monomer having a polar group. The polar group is a group having polarity. Examples of the polar group include at least one functional group selected from the group consisting of an amino group, a nitrile group, and an oxygen-containing polar group. Among these, at least one selected from the group consisting of a nitrile group and an oxygen-containing polar group is preferred, and an oxygen-containing polar group is more preferred.

[0041] Examples of the oxygen-containing polar group include a carbonyl group-containing group, an epoxy group, an oxetanyl group, and -SO3X a , -SO2X a , -OSO2X a , -PO3X a , and -OX a (In the formula, X a -H, metal atom, -NR 1 4. An imidazolium group which may have a substituent, a pyridinium group which may have a substituent, a phosphonium group which may have a substituent, an alkyl group, or a nitrile group. 1 is H or an organic group. Among these, the carbonyl group-containing group, -SO3X a , and -OX a At least one selected from the group consisting of a carbonyl group-containing group and -SO3X a At least one selected from the group consisting of:

[0042] The carbonyl group-containing group is, for example, -COOX a , -OCOX a (In the formula, X a is the same as above.), carbonate group, haloformyl group, acid anhydride residue, isocyanate group, etc. Among them, -COOX a , -OCOX a and at least one selected from the group consisting of acid anhydride residues, a and at least one selected from the group consisting of acid anhydride residues are more preferred.

[0043] X a -H, metal atom, -NR 1 4. An imidazolium group which may have a substituent, a pyridinium group which may have a substituent, or a phosphonium group which may have a substituent, an alkyl group, or a nitrile group. X a The metal atom in the formula (I) includes monovalent and divalent metal atoms, such as alkali metals (group 1) or alkaline earth metals (group 2), and specific examples thereof include Na, K, and Li. The Four Rs 1 may be the same or different. 1 is preferably H or an organic group having 1 to 10 carbon atoms, more preferably H or an organic group having 1 to 4 carbon atoms. X a The number of carbon atoms in the alkyl group is preferably 1 or more, preferably 10 or less, more preferably 6 or less, and even more preferably 4 or less. The alkyl group may be linear or cyclic. When the alkyl group is cyclic, it corresponds to a cycloalkyl group. X a is preferably -H, an alkali metal atom, NH4, an alkyl group, or a nitrile group, more preferably -H, an alkali metal atom, NH4, or an alkyl group, and even more preferably -H, an alkali metal atom, or NH4.

[0044] The polar group-containing monomer may be a non-fluorine-containing monomer or a fluorine-containing monomer, but is preferably a non-fluorine-containing monomer.

[0045] Examples of the fluorine-free monomer include hydroxyl group-containing fluorine-free monomers such as hydroxyalkyl vinyl ethers, such as hydroxyethyl vinyl ether, hydroxypropyl vinyl ether, hydroxybutyl vinyl ether, hydroxyisobutyl vinyl ether, and hydroxycyclohexyl vinyl ether; carboxyl group-containing fluorine-free monomers, such as acrylic acid, methacrylic acid, itaconic acid, succinic acid, fumaric acid, crotonic acid, maleic acid, citraconic acid, undecylenic acid, and acetylenedicarboxylic acid; itaconic anhydride (hereinafter also referred to as "IAH"), citraconic anhydride (hereinafter also referred to as "CAH"), 5-norbornene-2, Examples of the non-fluorine-containing monomer include 3-dicarboxylic acid anhydride (hereinafter also referred to as "NAH"), succinic anhydride, fumaric anhydride, maleic anhydride, and other non-fluorine-containing monomers having an acid anhydride residue; vinyl sulfonic acid, and other non-fluorine-containing monomers having a sulfo group; glycidyl vinyl ether, glycidyl allyl ether, and other non-fluorine-containing monomers having an epoxy group (glycidyl group); aminoalkyl vinyl ether, aminoalkyl allyl ether, and other non-fluorine-containing monomers having an amino group; (meth)acrylamide, methylolacrylamide, and other non-fluorine-containing monomers having an amide group; and acrylonitrile, methacrylonitrile, and other non-fluorine-containing monomers having a nitrile group. Among these, preferred are non-fluorine-containing monomers having a carboxyl group and non-fluorine-containing monomers having an acid anhydride residue, more preferred are non-fluorine-containing monomers having an acid anhydride residue, and even more preferred are cyclic non-fluorine-containing monomers having an acid anhydride residue. Non-fluorine-containing monomers having a carboxyl group and non-fluorine-containing monomers having a sulfo group are also preferred.

[0046] The fluorine-free monomer is also preferably a monomer (10) represented by the following general formula (10). Formula (10): CH2=CR 11 -L 11 -R 12 R 11 represents a hydrogen atom or an alkyl group. The alkyl group preferably has 1 to 3 carbon atoms, and more preferably 1 carbon atom. L 11 represents a single bond, -CO-O-*, -O-CO-* or -O-. * represents R 12 For example, L 11 is -CO-O-*, then equation (10) becomes CH2=CR 11 -CO-OR 12 Represents. R 12 represents a hydrogen atom, an alkyl group, or a nitrile group. The alkyl group preferably has 1 to 10 carbon atoms, more preferably 1 to 6 carbon atoms, and even more preferably 1 to 4 carbon atoms. The alkyl group may be linear or cyclic. When the alkyl group is cyclic, it corresponds to a cycloalkyl group.

[0047] The monomer (10) is preferably a monomer selected from the group consisting of a monomer represented by formula (10-1), a monomer represented by formula (10-2), a monomer represented by formula (10-3), and a monomer represented by formula (10-4). Formula (10-1) CH2=CR 11 -CO-OR 13 Formula (10-2) CH2=CR 11 -O-CO-R 14 Formula (10-3) CH2=CR 11 -OR 15 Formula (10-4) CH2=CR 11 -R 16 R 11 The definition of is as described above. R 13 represents a hydrogen atom or an alkyl group, preferably an alkyl group having 1 to 6 carbon atoms. R 14 represents an alkyl group, preferably an alkyl group having 1 to 3 carbon atoms, more preferably a methyl group. R 15 represents an alkyl group, preferably a linear alkyl group or a cyclic alkyl group. R 16 represents a nitrile group.

[0048] Examples of the monomer (10) include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate, vinyl methacrylate, vinyl acetate, acrylic acid, methacrylic acid, acrylonitrile, methacrylonitrile, ethyl vinyl ether, and cyclohexyl vinyl ether. As the monomer (10), a monomer represented by formula (10-1) and a monomer represented by formula (10-2) are more preferred, and R 13 A monomer represented by formula (10-1) in which is an alkyl group having 1 to 6 carbon atoms is particularly preferred.

[0049] The polar group-containing monomer preferably includes a modified monomer having a functional group reactive in radical polymerization and a hydrophilic group (hereinafter referred to as "modified monomer (A)").

[0050] Examples of the hydrophilic group in the modified monomer (A) include -NH2, -PO3M, -OPO3M, -SO3M, -OSO3M, and -COOM (in each formula, M represents H, a metal atom, or NR 7 4. An imidazolium which may have a substituent, a pyridinium which may have a substituent, or a phosphonium which may have a substituent, R 7 are H or organic groups and may be the same or different. Any two of them may be bonded to each other to form a ring. ) are examples of the hydrophilic group. Of these, -SO3M or -COOM is preferred. R 7 As for H or C 1-10 is preferably an organic group represented by the formula: 1-4 The organic group is more preferably H or C 1-4 More preferred are alkyl groups of the formula: The metal atom may be a monovalent or divalent metal atom, such as an alkali metal (Group 1) or an alkaline earth metal (Group 2), with Na, K, or Li being preferred.

[0051] Examples of the "functional group capable of reacting by radical polymerization" in the modifying monomer (A) include groups having an ethylenically unsaturated bond, such as a vinyl group and an allyl group. The group having an ethylenically unsaturated bond is a group represented by the following formula: CX e X g =CX f R- (In the formula, X e , X f and X g are each independently F, Cl, H, CF3, CF2H, CFH2, or CH3; and R is a linking group. The linking group for R can be represented by the formula: a Preferred linking groups include -CH=CH2 and -CF=CH 2、 -CH=CF 2、 Examples include groups having an unsaturated bond such as -CF=CF2, -CH2-CH=CH2, -CF2-CF=CH2, -CF2-CF=CF2, -(C=O)-CH=CH2, -(C=O)-CF=CH2, -(C=O)-CH=CF2, -(C=O)-CF=CF2, -(C=O)-C(CH3)=CH2, -(C=O)-C(CF3)=CH2, -(C=O)-C(CH3)=CF2, -(C=O)-C(CF3)=CF2, -O-CH2-CH=CH2, -O-CF2-CF=CH2, -O-CH2-CH=CF2, and -O-CF2-CF=CF2.

[0052] The modified monomer (A) has a functional group capable of reacting by radical polymerization, and therefore, when used in polymerization, it is presumed that it reacts with the fluorine-containing monomer at the initial stage of the polymerization reaction, forming highly stable particles having hydrophilic groups derived from the modified monomer (A). Therefore, it is considered that the number of particles increases when polymerization is carried out in the presence of the modified monomer (A).

[0053] The above-mentioned modifying monomer (A) may be used alone or in combination of two or more kinds.

[0054] As the modifying monomer (A), a compound having an unsaturated bond can be used.

[0055] The modifying monomer (A) is represented by the general formula (4): CX i X k =CX j R a -(CZ 1 Z 2 ) k -Y 3 (4) (In the formula, X i , X j and X k are each independently F, Cl, H, or CF; Y 3 is a hydrophilic group; R a is a linking group; Z 1 and Z 2 are each independently H, F or CF3, and k is 0 or 1). Examples of the hydrophilic group include -NH2, -PO3M, -OPO3M, -SO3M, -OSO3M, and -COOM (in each formula, M represents H, a metal atom, or NR 7 4. An imidazolium which may have a substituent, a pyridinium which may have a substituent, or a phosphonium which may have a substituent, R 7 are H or organic groups and may be the same or different. Any two of them may be bonded to each other to form a ring. ) are examples of the hydrophilic group. Of these, -SO3M or -COOM is preferred. R 7 As for H or C 1-10 is preferably an organic group represented by the formula: 1-4 The organic group is more preferably H or C 1-4 More preferred are alkyl groups of the formula: The metal atom may be a monovalent or divalent metal atom, such as an alkali metal (Group 1) or an alkaline earth metal (Group 2), with Na, K, or Li being preferred. By using the modifying monomer (A), an aqueous dispersion having a smaller average primary particle size and better stability can be obtained, and the aspect ratio of the primary particles can also be made smaller.

[0056] Above R ais a linking group. In this specification, the term "linking group" refers to a divalent linking group. The linking group may be a single bond and preferably contains at least one carbon atom, and the number of carbon atoms may be 2 or more, 4 or more, 8 or more, 10 or more, or 20 or more. There is no upper limit, but it may be, for example, 100 or less, or 50 or less. The linking group may be linear or branched, cyclic or acyclic, saturated or unsaturated, substituted or unsubstituted, and may optionally contain one or more heteroatoms selected from the group consisting of sulfur, oxygen, and nitrogen, and may optionally contain one or more functional groups selected from the group consisting of ester, amide, sulfonamide, carbonyl, carbonate, urethane, urea, and carbamate. The linking group may not contain carbon atoms but may be a catenary heteroatom such as oxygen, sulfur, or nitrogen.

[0057] Above R a is preferably a catenary heteroatom such as oxygen, sulfur, or nitrogen, or a divalent organic group. R a When R is a divalent organic group, the hydrogen atom bonded to the carbon atom may be replaced with a halogen other than fluorine, such as chlorine, and may or may not contain a double bond. a may be either linear or branched, and may be either cyclic or acyclic. a may contain functional groups (e.g., esters, ethers, ketones, amines, halides, etc.). R a may also be a non-fluorinated divalent organic group, or a partially fluorinated or perfluorinated divalent organic group. R aExamples of the hydrocarbon group include a hydrocarbon group in which no fluorine atoms are bonded to a carbon atom, a hydrocarbon group in which some of the hydrogen atoms bonded to a carbon atom are substituted with fluorine atoms, a hydrocarbon group in which all of the hydrogen atoms bonded to a carbon atom are substituted with fluorine atoms, -(C=O)-, -(C=O)-O-, or a hydrocarbon group containing -(C=O)-, which may contain an oxygen atom, a double bond, or a functional group.

[0058] R a is preferably —(C═O)—, —(C═O)—O—, or a hydrocarbon group having 1 to 100 carbon atoms which may contain an ether bond and may contain a carbonyl group, and in the hydrocarbon group, some or all of the hydrogen atoms bonded to the carbon atoms may be substituted with fluorine. R a Preferably, -(CH2) a -, -(CF2) a -, -O-(CF2) a -, -(CF2) a -O-(CF2) b -, -O(CF2) a -O-(CF2) b -, -(CF2) a -[O-(CF2) b ] c -, -O(CF2) a -[O-(CF2) b ] c -, -[(CF2) a -O] b -[(CF2) c -O] d -, -O[(CF2) a -O] b -[(CF2) c -O] d -, -O-[CF2CF(CF3)O] a -(CF2) b -, -(C=O)-, -(C=O)-O-, -(C=O)-(CH2) a -, -(C=O)-(CF2) a -, -(C=O)-O-(CH2) a -, -(C=O)-O-(CF2) a-, -(C=O)-[(CH2) a -O] b -, -(C=O)-[(CF2) a -O] b -, -(C=O)-O[(CH2) a -O] b -, -(C=O)-O[(CF2) a -O] b -, -(C=O)-O[(CH2) a -O] b -(CH2) c -, -(C=O)-O[(CF2) a -O] b -(CF2) c -, -(C=O)-(CH2) a -O-(CH2) b -, -(C=O)-(CF2) a -O-(CF2) b -, -(C=O)-O-(CH2) a -O-(CH2) b -, -(C=O)-O-(CF2) a -O-(CF2) b At least one selected from -, -(C=O)-O-C6H4-, and combinations thereof. In the formula, a, b, c, and d are independently at least 1. a, b, c, and d may independently be 2 or more, 3 or more, 4 or more, 10 or more, or 20 or more. The upper limit of a, b, c, and d is, for example, 100.

[0059] R aSpecific examples suitable as -CF2-O-, -CF2-O-CF2-, -CF2-O-CH2-, -CF2-O-CH2CF2-, -CF2-O-CF2CF2-, -CF2-O-CF2CH2-, -CF2-O-CF2CF2CH2-, -CF2-O-CF(CF3)-, -CF2-O-CF(CF3) CF2-, -CF2-O-CF(CF3)CF2-O-, -CF2-O-CF(CF3)CH2-, -(C=O)-, -(C=O)-O-, -(C=O)- (CH2)-, -(C=O)-(CF2)-, -(C=O)-O-(CH2)-, -(C=O)-O-(CF2)-, -(C=O)-[(CH2)2-O] n -, -(C=O)-[(CF2)2-O] n -, -(C=O)-O[(CH2)2-O] n -, -(C=O)-O[(CF2)2-O] n -, -(C=O)-O[(CH2)2-O] n -(CH2)-, -(C=O)-O[(CF2)2-O] n -(CF2)-, -(C=O)-(CH2)2-O-(CH2)-, -(C=O)-(CF2)2-O-(CF2)-, -(C=O)-O-(CH2)2-O-(CH2)-, -(C=O)-O-(CF2)2-O-(CF2)-, -(C=O)-O-C6H4-, etc. a Specifically, -CF2-O-, -CF2-O-CF2-, -CF2-O-CF2CF2-, -CF2-O-CF(CF3)-, -CF2-O-CF(CF3)CF2-, -CF2 -O-CF(CF3)CF2-O-, -(C=O)-, -(C=O)-O-, -(C=O)-(CH2)-, -(C=O)-O-(CH2)-, -(C=O)-O[(CH2)2-O] n -, -(C=O)-O[(CH2)2-O] n -(CH2)-, -(C=O)-(CH2)2-O-(CH2)-, or -(C=O)-O-C6H4- is preferred. In the above formula, n is an integer of 1 to 10.

[0060] -R in the above general formula (4) a -(CZ 1 Z 2) k としては、-CF2-O-CF2-、-CF2-O-CF(CF3)-、-CF2-OC(CF3)2-、-CF2-O-CF2-CF2-、-CF2-O-CF2-CF(CF3)-、-CF2-O-CF2-C(CF3)2-、-CF2-O-CF2CF2-CF2-、-CF2-O-CF2CF2-CF (CF3)-、-CF2-O-CF2CF2-C(CF3)2-、-CF2-O-CF(CF3)-CF2-、-CF2-O-CF(CF3)-CF(CF 3)-、-CF2-O-CF(CF3)-C(CF3)2-、-CF2-O-CF(CF3)-CF2-、-CF2-O-CF(CF3)-CF(CF3) -、-CF2-O-CF(CF3)-C(CF3)2-、-CF2-O-CF(CF3)CF2-CF2-、-CF2-O-CF(CF3)CF2-CF( CF3)-、-CF2-O-CF(CF3)CF2-C(CF3)2-、-CF2-O-CF(CF3)CF2-O-CF2-、-CF2-O-CF(CF 3)CF2-O-CF(CF3)-、-CF2-O-CF(CF3)CF2-OC(CF3)2-、-(C=O)-、-(C=O)-O-、-(C=O)- (CH2)-、-(C=O)-(CF2)-、-(C=O)-O-(CH2)-、-(C=O)-O-(CF2)-、-(C=O)-[(CH2)2-O] n -(CH2)-、-(C=O)-[(CF2)2-O] n -(CF2)-、-(C=O)-[(CH2)2-O] n -(CH2)-(CH2)-、-(C=O)-[(CF2)2-O] n -(CF2)-(CF2)-、-(C=O)-O[(CH2)2-O] n -(CF2)-、-(C=O)-O[(CH2)2-O] n -(CH2)-(CH2)-、-(C=O)-O[(CF2)2-O] n -(CF2)-、-(C=O)-O[(CF2)2-O] n-(CF2)-(CF2)-, -(C=O)-(CH2)2-O-(CH2)-(CH2)-, -(C=O)-(CF2)2-O-(CF2)-(CF2)-, -(C=O)-O-(CH2)2-O-(CH2)-(CH2)-, -(C=O )-O-(CF2)2-O-(CF2)-(CF2)-, -(C=O)-O-(CH2)2-O-(CH2)-C(CF3)2-, -(C=O)-O-(CF2)2-O-(CF2)-C(CF3)2-, or -(C=O)-O-C6H4- C(CF3)2- is preferred, -CF2-O-CF(CF3)-, -CF2-O-CF2-CF(CF3)-, -CF2-O-CF2CF2-CF(CF3)-, -CF2-O-CF(CF3)-CF(CF3)-, -CF2-O-CF(C F3)CF2-CF(CF3)-, -CF2-O-CF(CF3)CF2-O-CF(CF3)-, -(C=O)-, -(C=O)-O-(CH2)-, -(C=O)-O-(CH2)-(CH2)-, -(C=O)-O[(CH2)2-O] n -(CH2)-(CH2)-, -(C=O)-O-(CH2)2-O-(CH2)-C(CF3)2-, or -(C=O)-O-C6H4-C(CF3)2- is more preferred. In the above formula, n is an integer of 1 to 10.

[0061] Specific examples of the compound represented by general formula (4) include: [ka] (In the formula, X j and Y 3 is the same as above. n is an integer of 1 to 10.

[0062] R a The following general formula (r1): -(C=O) h -(O) i -CF2-O-(CX 6 2) e -{O-CF(CF3)} f -(O) g -(r1) (In the formula, X 6are each independently H, F, or CF3, e is an integer of 0 to 3, f is an integer of 0 to 3, g is 0 or 1, h is 0 or 1, and i is 0 or 1), and a divalent group represented by the following general formula (r2): -(C=O) h -(O) i -CF2-O-(CX 7 2) e -(O) g -(r2) (In the formula, X 7 are each independently H, F or CF3, e is an integer of 0 to 3, g is 0 or 1, h is 0 or 1, and i is 0 or 1. Divalent groups represented by the following formula are also preferred.

[0063] -R in the above general formula (4) a -CZ 1 Z 2 - can also be represented by the following formula (t1): -(C=O) h -(O) i -CF2-O-(CX 6 2) e -{O-CF(CF3)} f -(O) g -CZ 1 Z 2 -(t1) (In the formula, X 6 are each independently H, F, or CF3, e is an integer of 0 to 3, f is an integer of 0 to 3, g is 0 or 1, h is 0 or 1, i is 0 or 1, and Z 1 and Z 2 are each independently F or CF3), and in formula (t1), Z 1 and Z 2 More preferably, one is F and the other is CF3. In addition, in the above general formula (4), -R a -CZ 1 Z 2 - is the following formula (t2): -(C=O) h -(O) i -CF2-O-(CX 7 2)e -(O) g -CZ 1 Z 2 -(t2) (In the formula, X 7 are each independently H, F, or CF3, e is an integer of 0 to 3, g is 0 or 1, h is 0 or 1, i is 0 or 1, and Z 1 and Z 2 are each independently H, F or CF3), and in formula (t2), Z 1 and Z 2 More preferably, one is F and the other is CF3.

[0064] The compound represented by the general formula (4) is a hydrophilic group (Y 3 ), it is also preferable that the compound has a C—F bond and does not have a C—H bond. i , X j , and X k All of the are F and R a is preferably a perfluoroalkylene group having one or more carbon atoms, and the perfluoroalkylene group may be either linear or branched, may be cyclic or acyclic, and may contain at least one catenary heteroatom. The number of carbon atoms in the perfluoroalkylene group may be 2 to 20, or may be 4 to 18.

[0065] The compound represented by the general formula (4) may be partially fluorinated. That is, the compound represented by the general formula (4) may have a hydrophilic group (Y 3 ), it is also preferred that the alkyl group has at least one hydrogen atom bonded to a carbon atom and at least one fluorine atom bonded to a carbon atom.

[0066] The compound represented by general formula (4) is also preferably a compound represented by the following formula (4a). CF2=CF-O-Rf 0 -Y 3 (4a) (In the formula, Y 3 is a hydrophilic group, and Rf 0is a perfluorinated divalent linking group which may be linear or branched, cyclic or acyclic in structure, saturated or unsaturated, substituted or unsubstituted, and which optionally contains one or more heteroatoms selected from the group consisting of sulfur, oxygen, and nitrogen.

[0067] The compound represented by general formula (4) is also preferably a compound represented by the following formula (4b). CH2=CH-O-Rf 0 -Y 3 (4b) (In the formula, Y 3 is a hydrophilic group, and Rf 0 is a perfluorinated divalent linking group defined by formula (4a).

[0068] In general formula (4), Y 3 One of the preferred embodiments is -OSO3M. 3 is -OSO3M, examples of the polymerized units based on the compound represented by general formula (4) include -[CF2CF(OCF2CF2CH2OSO3M)]-, -[CH2CH((CF2)4CH2OSO3M)]-, -[CF2CF(O(CF2)4CH2OSO3M)]-, -[CF2CF(OCF2CF(CF3)CH2OSO3M)]-, -[CF2CF(OCF2CF(CF3)OCF2CF2CH2OSO3M)]-, -[CH2CH((CF2)4CH2OSO3M)]-, -[CF2CF(OCF2CF2SO2N(CH3) In the above formula, M is the same as above.

[0069] In general formula (4), Y 3 Another preferred form is -SO3M. 3is -SO3M, examples of polymerized units based on the compound represented by general formula (4) include -[CF2CF(OCF2CF2SO3M)]-, -[CF2CF(O(CF2)4SO3M)]-, -[CF2CF(OCF2CF(CF3)SO3M)]-, -[CF2CF(OCF2CF(CF3)OCF2CF2SO3M)]-, -[CH2CH(CF2CF2SO3M)]-, -[CF2CF(OCF2CF(CF3)OCF2CF2CF2CF2SO3M)]-, -[CH2CH((CF2)4SO3M)]-, -[CH2CH(CF2CF2SO3M)]-, -[CH2CH(CF2CF2SO3M)]-, and the like. In the above formulas, M is the same as above.

[0070] In general formula (4), Y 3 -COOM is also a preferred form. 3 is -COOM, the polymerized units based on the compound represented by general formula (4) include -[CFCF(OCFCFCOOM)]-, -[CFCF(O(CF)COOM)]-, -[CFCF(OCFCF(CF)COOM)]-, -[CFCF(OCFCF(CF)O(CF) n COOM)]-(n is greater than 1), -[CH2CH(CF2CF2COOM)]-, -[CH2CH((CF2)4COOM)]-, -[CH2CH(CF2CF2COOM)]-, -[CH2CH((CF2)4COOM)]-, -[CF2CF(OCF2CF2SO2NR'CH2COOM)]-, -[CF2CF(O(CF2)4SO2NR'CH2COOM)]-, -[CF2CF(OCF2CF(CF3)SO2NR'CH2COOM)]-, -[CF2CF( OCF2CF(CF3)OCF2CF2SO2NR'CH2COOM)]-, -[CH2CH(CF2CF2SO2NR'CH2COOM)]-, -[CF2CF(OCF2CF(CF3)OCF2CF2CF2CF2SO2NR'CH2COOM)]-, -[CH2CH((CF2)4SO2NR'CH2COOM)]-, -[CH2CH(CF2CF2SO2NR'CH2COOM)]-, -[CH2CH((CF2)4SO2NR'CH2COOM)]-, etc. In the above formula, R' represents H or C1-4 is an alkyl group, and M is the same as above.

[0071] In general formula (4), Y 3 In another preferred embodiment, Y is -OPO3M. 3 is -OPO3M, examples of the polymerized units based on the compound represented by general formula (4) include -[CF2CF(OCF2CF2CH2OP(O)(OM)2)]-, -[CF2CF(O(CF2)4CH2OP(O)(OM)2)]-, -[CF2CF(OCF2CF(CF3)CH2OP(O)(OM)2)]-, -[CF2CF(OCF2CF(CF3)OCF2CF2CH2OP(O)(OM)2)]-, -[CF2CF(OCF2CF2SO2N(C H3)CH2CH2OP(O)(OM)2)]-, -[CF2CF(OCF2CF2CF2CF2SO2N(CH3)CH2CH2OP(O)(OM)2)]-, -[CH2CH(CF2CF2CH2OP(O)(OM)2)]-, -[CH2CH((CF2)4CH2OP(O)(OM)2)]-, -[CH2CH(CF2CF2CH2OP(O)(OM)2)]-, -[CH2CH((CF2)4CH2OP(O)(OM)2)]-, etc. In the above formula, M is the same as above.

[0072] In general formula (4), Y 3 In another preferred embodiment, Y is -PO3M. 3 is -PO3M, examples of the polymerized units based on the compound represented by general formula (4) include -[CF2CF(OCF2CF2P(O)(OM)2)]-, -[CF2CF(O(CF2)4P(O)(OM)2)]-, -[CF2CF(OCF2CF(CF3)P(O)(OM)2)]-, -[CF2CF(OCF2CF(CF3)OCF2CF2P(O)(OM)2)]-, -[CH2CH(CF2CF2P(O)(OM)2)]-, -[CH2CH((CF2)4P(O)(OM)2)]-, -[CH2CH(CF2CF2P(O)(OM)2)]-, and -[CH2CH((CF2)4P(O)(OM)2)]-, where M is the same as above.

[0073] The compound represented by the above general formula (4) includes compounds represented by the following general formula (5): CX2=CY(-CZ2-O-Rf-Y 3 )(5) (In the formula, X's may be the same or different and each represent -H or -F; Y's may be -H, -F, an alkyl group or a fluorine-containing alkyl group; and Z's may be the same or different and each represent -H, -F, an alkyl group or a fluorine-containing alkyl group. Rf's may be a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and an ether bond. Y 3 is the same as above, a monomer represented by the following general formula (6): CX2=CY(-O-Rf-Y 3 )(6) (In the formula, X may be the same or different and is -H or -F; Y is -H, -F, an alkyl group or a fluorine-containing alkyl group; and Rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and an ether bond. Y 3 is the same as above.) and a monomer represented by the following general formula (7): CX2=CY(-Rf-Y 3 )(7) (In the formula, X may be the same or different and is -H or -F; Y is -H, -F, an alkyl group or a fluorine-containing alkyl group; and Rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and an ether bond. Y 3 is the same as above. Preferably, the monomer is at least one selected from the group consisting of:

[0074] In the above general formula (5), X is -H or -F. Both Xs may be -F, or at least one X may be -H. For example, one X may be -F and the other may be -H, or both Xs may be -H.

[0075] In the above general formula (5), Y is —H, —F, an alkyl group or a fluorine-containing alkyl group. The alkyl group is an alkyl group that does not contain a fluorine atom, and may have a carbon number of at least 1. The alkyl group preferably has 6 or less carbon atoms, more preferably 4 or less carbon atoms, and even more preferably 3 or less carbon atoms. The fluorine-containing alkyl group is an alkyl group containing at least one fluorine atom, and may have a carbon number of at least 1. The fluorine-containing alkyl group preferably has 6 or less carbon atoms, more preferably 4 or less carbon atoms, and even more preferably 3 or less carbon atoms. The above Y is preferably -H, -F or -CF3, and more preferably -F.

[0076] In the above general formula (5), Z may be the same or different and is —H, —F, an alkyl group or a fluoroalkyl group. The alkyl group is an alkyl group that does not contain a fluorine atom, and may have a carbon number of at least 1. The alkyl group preferably has 6 or less carbon atoms, more preferably 4 or less carbon atoms, and even more preferably 3 or less carbon atoms. The fluorine-containing alkyl group is an alkyl group containing at least one fluorine atom, and may have a carbon number of at least 1. The fluorine-containing alkyl group preferably has 6 or less carbon atoms, more preferably 4 or less carbon atoms, and even more preferably 3 or less carbon atoms. The above Z is preferably -H, -F or -CF3, and more preferably -F.

[0077] In the general formula (5), it is preferable that at least one of X, Y, and Z contains a fluorine atom. For example, X may be —H, and Y and Z may be —F.

[0078] In the general formula (5), Rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms, or a fluorine-containing alkylene group having 2 to 100 carbon atoms and an ether bond. The number of carbon atoms in the fluorine-containing alkylene group is preferably 2 or more. Also, it is preferably 30 or less, more preferably 20 or less, and even more preferably 10 or less. Examples of the fluorine-containing alkylene group include -CF2-, -CH2CF2-, -CF2CF2-, -CF2CH2-, -CF2CF2CH2-, -CF(CF3)-, -CF(CF3)CF2-, and -CF(CF3)CH2-. The fluorine-containing alkylene group is preferably a perfluoroalkylene group.

[0079] The number of carbon atoms in the fluorine-containing alkylene group having an ether bond is preferably 3 or more, and more preferably 60 or less, more preferably 30 or less, and even more preferably 12 or less. For example, the following formula: [ka] (In the formula, Z 1 is F or CF3;Z 2 and Z 3 are H or F;Z respectively 4 is H, F, or CF3; p1+q1+r1 are integers from 0 to 10; s1 is 0 or 1; t1 is an integer from 0 to 5, except for Z 3 and Z 4 are both H, it is also preferable that p1+q1+r1+s1 is not 0). Specific examples of the fluorine-containing alkylene group having an ether bond include -CF(CF3)CF2-O-CF(CF3)-, -(CF(CF3)CF2-O) n -CF(CF3)- (wherein n is an integer of 1 to 10), -CF(CF3)CF2-O-CF(CF3)CH2-, -(CF(CF3)CF2-O) n Examples thereof include -CF(CF3)CH2- (wherein n is an integer of 1 to 10), -CH2CF2CF2O-CH2CF2CH2-, -CF2CF2CF2O-CF2CF2-, -CF2CF2CF2O-CF2CF2CH2-, -CF2CF2O-CF2-, -CF2CF2O-CF2CH2-, -CF2CF2O-CF2CH2-, -CF2CF2O-CF2CH2-, -CF(CF3)CH2-, and the like. The fluorine-containing alkylene group having an ether bond is preferably a perfluoroalkylene group.

[0080] In the above general formula (5), Y 3 is -COOM, -SO3M or -OSO3M (M is H, a metal atom, NR 7 4. An imidazolium which may have a substituent, a pyridinium which may have a substituent, or a phosphonium which may have a substituent, R 7 are H or organic groups and may be the same or different. Any two of them may be bonded to each other to form a ring. R 7 As for H or C 1-10 is preferably an organic group represented by the formula: 1-4 The organic group is more preferably H or C 1-4 More preferred are alkyl groups of the formula: The metal atom includes alkali metals (Group 1) and alkaline earth metals (Group 2), and is preferably Na, K or Li. The above M is —H, a metal atom, or —NR 7 4 is preferred, and -H, an alkali metal (Group 1), an alkaline earth metal (Group 2) or -NR 7 4 is more preferred, -H, -Na, -K, -Li or -NH4 is even more preferred, -Na, -K or -NH4 is even more preferred, -Na or -NH4 is especially preferred, and -NH4 is most preferred. Above Y 3 As the alkyl group, -COOM or -SO3M is preferred, and -COOM is more preferred.

[0081] Examples of the monomer represented by general formula (5) include the following formula (5a): CX h 2=CFCF2-O-(CF(CF3)CF2O) n5 -CF(CF3)-Y 3 (5a) (In the formula, each h are the same and represent F or H. n5 represents 0 or an integer of 1 to 10, and Y 3 is the same as defined above. ) is a suitable example of a fluoroallyl ether compound. In the general formula (5a), n5 is preferably 0 or an integer of 1 to 5, more preferably 0, 1 or 2, and even more preferably 0 or 1, in that TFE-based polymer particles having a small primary particle size can be obtained. 3 is preferably -COOM in that it provides suitable water solubility and surface activity, and the above M is preferably H or NH4 in that it is less likely to remain as an impurity and the heat resistance of the resulting composition and the stretched body obtained from the composition is improved.

[0082] The monomer represented by the general formula (5) is preferably a monomer (5b) represented by the following general formula (5b). CH2=CF(-CF2-O-Rf-Y 3 )(5b) (Wherein Rf and Y 3 is the same as above.)

[0083] Specific examples of the monomer represented by the general formula (5b) include those represented by the following formula:

[0084] [ka]

[0085] (In the formula, Z 1 is F or CF3;Z 2 and Z 3 are H or F;Z respectively 4 is H, F, or CF3; p1+q1+r1 are integers between 0 and 10; s1 is 0 or 1; t1 is an integer between 0 and 5; Y 3 is the same as above, except for Z 3 and Z 4 are both H, then p1+q1+r1+s1 is not 0). More specifically,

[0086] [ka]

[0087] Among them,

[0088] [ka]

[0089] It is preferable that:

[0090] The monomer represented by the general formula (5b) includes, for example, Y 3 is preferably -COOM, and particularly preferably at least one selected from the group consisting of CH2=CFCF2OCF(CF3)COOM and CH2=CFCF2OCF(CF3)CF2OCF(CF3)COOM (wherein M is as defined above), and more preferably CH2=CFCF2OCF(CF3)COOM.

[0091] The monomer represented by the general formula (5) is preferably a monomer (5c) represented by the following general formula (5c). CX 2 2=CFCF2-O-(CF(CF3)CF2O) n5 -CF(CF3)-Y 3 (5c) (In the formula, each 2 are the same and represent F or H. n5 represents 0 or an integer of 1 to 10, and Y 3 is the same as the definition above.)

[0092] In the formula (5c), n5 is preferably 0 or an integer of 1 to 5, more preferably 0, 1 or 2, and even more preferably 0 or 1, in terms of the stability of the resulting aqueous dispersion. 3 -COOM is advantageous in that it provides moderate water solubility and stability of aqueous dispersion. 1 It is preferable that the above M 1 is preferably H or NH4, since it is unlikely to remain as an impurity and the heat resistance of the resulting molded article is improved.

[0093] Examples of the perfluorovinyl alkyl compound represented by the formula (5c) include CH2=CFCF2OCF(CF3)COOM 1, CH2=CFCF2OCF(CF3)CF2OCF(CF3)COOM 1 (In the formula, M 1 is the same as the definition above.

[0094] Furthermore, examples of the monomer represented by general formula (5) include a monomer represented by the following general formula (5d) and a monomer represented by the following general formula (5e).

[0095] CF2=CFCF2-O-Rf-Y 3 (5d) CF2=CF-Rf-Y 3 (5e) (Wherein Rf and Y 3 is the same as above)

[0096] More specifically, [ka] etc.

[0097] In the above general formula (6), X is -H or -F. Both Xs may be -F, or at least one X may be -H. For example, one X may be -F and the other may be -H, or both Xs may be -H.

[0098] In the above general formula (6), Y is —H, —F, an alkyl group or a fluorine-containing alkyl group. The alkyl group is an alkyl group that does not contain a fluorine atom, and may have a carbon number of at least 1. The alkyl group preferably has 6 or less carbon atoms, more preferably 4 or less carbon atoms, and even more preferably 3 or less carbon atoms. The fluorine-containing alkyl group is an alkyl group containing at least one fluorine atom, and may have a carbon number of at least 1. The fluorine-containing alkyl group preferably has 6 or less carbon atoms, more preferably 4 or less carbon atoms, and even more preferably 3 or less carbon atoms. The above Y is preferably -H, -F or -CF3, and more preferably -F.

[0099] In the general formula (6), it is preferable that at least one of X and Y contains a fluorine atom. For example, X may be —H, and Y and Z may be —F.

[0100] In the general formula (6), Rf is a fluorine-containing alkylene group having 1 to 40 carbon atoms or a fluorine-containing alkylene group having 2 to 100 carbon atoms and an ether bond. The number of carbon atoms in the fluorine-containing alkylene group is preferably 2 or more. Also, it is preferably 30 or less, more preferably 20 or less, and even more preferably 10 or less. Examples of the fluorine-containing alkylene group include -CF2-, -CH2CF2-, -CF2CF2-, -CF2CH2-, -CF2CF2CH2-, -CF(CF3)-, -CF(CF3)CF2-, and -CF(CF3)CH2-. The fluorine-containing alkylene group is preferably a perfluoroalkylene group.

[0101] The monomer represented by the above general formula (6) is preferably at least one selected from the group consisting of monomers represented by the following general formulae (6a), (6b), (6c) and (6d). CF2=CF-(CF2) n1 -Y 3 (6a) (wherein n1 represents an integer of 1 to 10, and Y 3 -SO3M 1 or -COOM 1 represents M 1 is H, metal atom, NR 7 4. An imidazolium which may have a substituent, a pyridinium which may have a substituent, or a phosphonium which may have a substituent, R 7 represents H or an organic group. CF2=CF-(CF2C(CF3)F) n2 -Y 3 (6b) (wherein n2 represents an integer of 1 to 5, and Y 3 is the same as the definition above.) CF2=CF-O-(CFX 1 ) n3 -Y 3 (6c) (In the formula, X1 represents F or CF3, n3 represents an integer of 1 to 10, and Y 3 is the same as the definition above.) CF2=CF-O-(CF2CFX 1 O) n4 -CF2CF2-Y 3 (6d) (wherein n4 represents an integer of 1 to 10, and Y 3 and X 1 is the same as the definition above.)

[0102] In the formula (6a), n1 is preferably an integer of 5 or less, and more preferably an integer of 2 or less. 3 -COOM is advantageous in that it can provide adequate water solubility and stability of the aqueous dispersion. 1 Preferably, M 1 is preferably H or NH4, since it is unlikely to remain as an impurity and the heat resistance of the resulting molded article is improved.

[0103] The perfluorovinyl alkyl compound represented by the above formula (6a) is, for example, CF2=CFCF2COOM 1 (In the formula, M 1 is the same as the definition above.

[0104] In the formula (6b), n2 is preferably an integer of 3 or less in terms of the stability of the resulting aqueous dispersion, and Y 3 -COOM is advantageous in that it provides adequate water solubility and stability of the aqueous dispersion. 1 Preferably, M 1 is preferably H or NH4, since it is unlikely to remain as an impurity and the heat resistance of the resulting molded article is improved.

[0105] In the formula (6c), n3 is preferably an integer of 5 or less in terms of water solubility, and Y 3 -COOM is advantageous in that it provides adequate water solubility and stability of the aqueous dispersion. 1 It is preferable that the above M 1is preferably H or NH4 in terms of improving dispersion stability.

[0106] In the above formula (6d), the above X 1 is preferably —CF3 from the viewpoint of stability of the aqueous dispersion, n4 is preferably an integer of 5 or less from the viewpoint of water solubility, and Y 3 -COOM is advantageous in that it provides moderate water solubility and stability of aqueous dispersion. 1 It is preferable that the above M 1 is preferably H or NH4.

[0107] Examples of the perfluorovinyl ether compound represented by the above formula (6d) include CF2=CFOCF2CF(CF3)OCF2CF2COOM 1 (In the formula, M 1 represents H, NH4 or an alkali metal.

[0108] In the above general formula (7), Rf is preferably a fluorine-containing alkylene group having a carbon number of 1 to 40. In general formula (7), at least one of X and Y preferably contains a fluorine atom.

[0109] The monomer represented by the above general formula (7) is represented by the following general formula (7a): CF2=CF-(CF2) n1 -Y 3 (7a) (wherein n1 represents an integer of 1 to 10, and Y 3 is as defined above.) and a monomer represented by the following general formula (7b): CF2=CF-(CF2C(CF3)F) n2 -Y 3 (7b) (wherein n2 represents an integer of 1 to 5, and Y 3 is as defined above. At least one selected from the group consisting of monomers represented by Above Y 3 -SO3M 1 or -COOM 1 is preferred, and M 1is H, metal atom, NR 7 4. It is preferably an imidazolium which may have a substituent, a pyridinium which may have a substituent, or a phosphonium which may have a substituent. 7 represents H or an organic group.

[0110] In the formula (7a), n1 is preferably an integer of 5 or less, and more preferably an integer of 2 or less. 3 -COOM is advantageous in that it can provide adequate water solubility and stability of the aqueous dispersion. 1 Preferably, M 1 is preferably H or NH4, since it is unlikely to remain as an impurity and the heat resistance of the resulting molded article is improved. The perfluorovinyl alkyl compound represented by the above formula (7a) is, for example, CF2=CFCF2COOM 1 (In the formula, M 1 is the same as the definition above.

[0111] In the formula (7b), n2 is preferably an integer of 3 or less in terms of the stability of the resulting aqueous dispersion, and Y 3 -COOM is advantageous in that it provides adequate water solubility and stability of the aqueous dispersion. 1 Preferably, M 1 is preferably H or NH4, since it is unlikely to remain as an impurity and the heat resistance of the resulting molded article is improved.

[0112] The modifying monomer (A) is preferably at least one selected from the group consisting of compounds represented by general formula (5c), general formula (6a), general formula (6b), general formula (6c), and general formula (6d), and more preferably a compound represented by general formula (5c).

[0113] The content of the polymerized units based on the monomer having a polar group (monomer units having a polar group) is preferably in the range of 0.0001 to 1.0% by mass relative to the total polymerized units, from the viewpoints of improving cycle characteristics, suppressing gas generation, and obtaining a composite sheet having excellent strength and flexibility. The lower limit of the content of the monomer units having a polar group is more preferably 0.0005% by mass, even more preferably 0.001% by mass, and even more preferably 0.002% by mass. The upper limit of the content of the monomer units having a polar group is more preferably 0.8% by mass, even more preferably 0.5% by mass, even more preferably 0.3% by mass, even more preferably 0.2% by mass, and particularly preferably 0.1% by mass.

[0114] The total amount of polymerized units based on TFE (TFE units) and monomer units having a polar group is preferably 95.0% by mass or more, more preferably 97.0% by mass or more, even more preferably 99.0% by mass or more, still more preferably 99.5% by mass or more, and particularly preferably 99.9% by mass or more, based on the total polymerized units. The upper limit is not particularly limited, and may be, for example, 100% by mass.

[0115] The TFE-based polymer may further contain polymerized units (other monomer units) based on monomers (other monomers) other than TFE and the monomer having a polar group.

[0116] The other monomer is not particularly limited as long as it is copolymerizable with TFE and a monomer having a polar group, and examples thereof include perfluoroolefins such as hexafluoropropylene (HFP), hydrogen-containing fluoroolefins such as trifluoroethylene and vinylidene fluoride (VDF), perhaloolefins such as chlorotrifluoroethylene (CTFE), perfluorovinyl ether, perfluoroallyl ether, (perfluoroalkyl)ethylene, ethylene, etc. The other monomer used may be one type or multiple types.

[0117] The perfluorovinyl ether is not particularly limited, and examples thereof include perfluorovinyl ethers represented by the following general formula (A): CF2=CF-ORf 1 (A) (In the formula, Rf 1 represents a perfluoroorganic group. ) and perfluorounsaturated compounds represented by the following formula (I) are included. In this specification, the "perfluoroorganic group" refers to an organic group in which all hydrogen atoms bonded to carbon atoms are substituted with fluorine atoms. The perfluoroorganic group may have an ether oxygen.

[0118] The perfluorovinyl ether may be, for example, a compound represented by the general formula (A) in which Rf 1 is a perfluoroalkyl group having 1 to 10 carbon atoms. The number of carbon atoms in the perfluoroalkyl group is preferably 1 to 5.

[0119] Examples of the perfluoroalkyl group in the PAVE include a perfluoromethyl group, a perfluoroethyl group, a perfluoropropyl group, a perfluorobutyl group, a perfluoropentyl group, and a perfluorohexyl group.

[0120] The perfluorovinyl ether further includes a compound represented by the general formula (A) in which Rf 1 is a perfluoro(alkoxyalkyl) group having 4 to 9 carbon atoms, Rf 1 is the following formula:

[0121] [ka]

[0122] (wherein m represents 0 or an integer of 1 to 4), Rf 1 is the following formula:

[0123] [ka]

[0124] (wherein n represents an integer of 1 to 4).

[0125] The (perfluoroalkyl)ethylene [PFAE] is not particularly limited, and examples thereof include (perfluorobutyl)ethylene [PFBE] and (perfluorohexyl)ethylene.

[0126] Examples of perfluoroallyl ethers include those represented by the general formula (B): CF2=CF-CF2-ORf 2 (B) (In the formula, Rf 2 represents a perfluoroorganic group.

[0127] Above Rf 2 is preferably a perfluoroalkyl group having 1 to 10 carbon atoms or a perfluoroalkoxyalkyl group having 1 to 10 carbon atoms. The perfluoroallyl ether is preferably at least one selected from the group consisting of CF2=CF-CF2-O-CF3, CF2=CF-CF2-O-C2F5, CF2=CF-CF2-O-C3F7, and CF2=CF-CF2-O-C4F9, more preferably at least one selected from the group consisting of CF2=CF-CF2-O-C2F5, CF2=CF-CF2-O-C3F7, and CF2=CF-CF2-O-C4F9, and even more preferably CF2=CF-CF2-O-CF2CF2CF3.

[0128] The other monomers are represented by the following general formula (i): CX 1 X 2 =CX 3 X 4 (i) (In the formula, X 1 ~X 3 are each independently H or F. 4 is F, Cl, Rf or O-Rf. Rf is a perfluoro organic group.

[0129] Rf in general formula (i) is preferably a perfluoroalkyl group having 1 to 10 carbon atoms, more preferably a perfluoroalkyl group having 1 to 5 carbon atoms, and even more preferably a perfluoroalkyl group having 1 to 4 carbon atoms.

[0130] As the other monomer, in terms of improving the stretchability, binding strength, and flexibility of the composite sheet, at least one selected from the group consisting of HFP, PAVE, and PFAE is preferred, at least one selected from the group consisting of HFP, perfluoro(methyl vinyl ether) [PMVE], perfluoro(propyl vinyl ether) [PPVE], and PFBE is more preferred, at least one selected from the group consisting of HFP, PMVE, and PPVE is even more preferred, at least one selected from the group consisting of HFP and PPVE is even more preferred, and HFP is even more preferred.

[0131] The TFE polymer may be a TFE copolymer containing TFE units and polymerized units (modified monomer units) based on a modified monomer copolymerizable with TFE. The modified monomer includes the above-mentioned monomer having a polar group and other monomers. The TFE-based polymer is preferably polytetrafluoroethylene (PTFE) in terms of improving cycle characteristics, suppressing gas generation, and obtaining a composite sheet excellent in strength and flexibility, and is more preferably a modified PTFE containing 99.0% by mass or more of TFE units and 1.0% by mass or less of modified monomer units.

[0132] The content of the modified monomer units (total amount of monomer units having a polar group and other monomer units) is preferably in the range of 0.0001 to 10% by mass relative to all polymerized units, from the viewpoints of improving cycle characteristics, suppressing gas generation, and obtaining a composite sheet with excellent strength and flexibility. The lower limit of the content of the modified monomer units is more preferably 0.001% by mass, even more preferably 0.010% by mass, even more preferably 0.015% by mass, and particularly preferably 0.020% by mass. The upper limit of the content of the modified monomer units is preferably 5.0% by mass, more preferably 3.0% by mass, even more preferably 1.0% by mass, even more preferably 0.80% by mass, even more preferably 0.60% by mass, even more preferably 0.50% by mass, even more preferably 0.40% by mass, even more preferably 0.30% by mass, and particularly preferably 0.20% by mass. In this specification, the modified monomer unit means a part of the molecular structure of the TFE polymer that is derived from the modified monomer.

[0133] The content of each of the above-mentioned polymerized units can be calculated by appropriately combining NMR, FT-IR, elemental analysis, and X-ray fluorescence analysis depending on the type of monomer.

[0134] The TFE polymer may have a core-shell structure. Examples of TFE polymers having a core-shell structure include modified PTFE particles containing a core of high molecular weight PTFE and a shell of lower molecular weight PTFE or modified PTFE. Examples of such modified PTFE include the PTFE described in JP-A-2005-527652.

[0135] The TFE-based polymer is preferably non-melt processable. In this specification, non-melt-processable means that the melt flow rate (MFR) is less than 0.25 g / 10 min, preferably less than 0.10 g / 10 min, more preferably 0.05 g / 10 min or less, and even more preferably 0.01 g / 10 min or less. The MFR is a value obtained in accordance with ASTM D1238 using a melt indexer, as the mass (g / 10 min) of polymer flowing out of a nozzle having an inner diameter of 2.095 mm and a length of 8 mm at 372°C under a load of 5 kg per 10 min.

[0136] The content of the TFE polymer in the TFE polymer composition (1) of the present disclosure may be 95.0% by mass or more, preferably 98.0% by mass or more, more preferably 99.0% by mass or more, even more preferably 99.5% by mass or more, particularly preferably 99.9% by mass or more, and most preferably 99.95% by mass or more, based on the TFE polymer composition.

[0137] The TFE-based polymer composition (1) of the present disclosure may contain a fluorine-containing compound having a hydrophilic group.

[0138] The hydrophilic group is, for example, -SO3M a , -SO2M a , -OSO2M a , -PO3M a , -COOM a , -OCOM a , and -OM a (In the formula, M a -H, metal atom, -NR 1 4. An optionally substituted imidazolium, an optionally substituted pyridinium, or an optionally substituted phosphonium, wherein R 1 is H or an organic group. The hydrophilic group may be an ionic group, and is preferably an anionic group.

[0139] Examples of the fluorine-containing compound having a hydrophilic group include a fluorine-containing compound having a hydrophilic group with a molecular weight of 1000 or less, i.e., a fluorine-containing compound having a hydrophilic group with a molecular weight of 1000 g / mol or less. The molecular weight of the fluorine-containing compound is preferably 800 or less, and more preferably 500 or less. Polymer particles obtained by polymerization in the presence of a fluorine-containing surfactant usually contain a fluorine-containing surfactant in addition to the TFE polymer. In this specification, the fluorine-containing surfactant is one that is used during polymerization. The fluorine-containing compound having a molecular weight of 1,000 or less may be a compound that is not added during polymerization, for example, a compound that is produced as a by-product during polymerization. When the fluorine-containing compound having a molecular weight of 1000 or less contains an anionic moiety and a cationic moiety, the fluorine-containing compound has a molecular weight of 1000 or less in the anionic moiety. The fluorine-containing compound having a molecular weight of 1000 or less does not include TFE polymers.

[0140] Examples of the fluorine-containing compound having a hydrophilic group with a molecular weight of 1000 or less include surfactants (anionic fluorine-containing surfactants) whose anionic moiety contains fluorine and whose molecular weight is 1000 or less. The "anionic moiety" refers to the portion of the fluorine-containing surfactant excluding the cation. For example, F(CF2) n1 In the case of COOM, "F(CF2) n1 The "COO" part.

[0141] The anionic fluorine-containing surfactants include those represented by the general formula (N 0 ): X n0 -Rf n0 -Y 0 (N 0 ) (In the formula, X n0 is H, Cl or F. n0 is a linear, branched or cyclic alkylene group having 3 to 20 carbon atoms, in which some or all of the H atoms have been substituted with F, and the alkylene group may contain one or more ether bonds, and some of the H atoms may have been substituted with Cl. Y 0 is an anionic group.

[0142] Y 0The anionic group may be -COOM, -SO2M, or -SO3M, where M is H, a metal atom, NR 7 4. An optionally substituted imidazolium, an optionally substituted pyridinium, or an optionally substituted phosphonium, wherein R 7 is H or an organic group. The metal atom includes alkali metals (Group 1) and alkaline earth metals (Group 2), such as Na, K, or Li. 7 As for H or C 1-10 and may be an organic group of H or C 1-4 and may be an organic group of H or C 1-4 M may be an alkyl group of the formula: H, a metal atom, or NR 7 4, and may be H, an alkali metal (Group 1), an alkaline earth metal (Group 2), or NR 7 4, and may be H, Na, K, Li, or NH4. n0 may be one in which 50% or more of H is substituted with fluorine.

[0143] General formula (N 0 The compound represented by the general formula (N 1 ): X n0 -(CF2) m1 -Y 0 (N 1 ) (In the formula, X n0 is H, Cl, and F, m1 is an integer from 3 to 15, and Y 0 is as defined above, a compound represented by the general formula (N 2 ): Rf n1 -O-(CF(CF3)CF2O) m2 CFX n1 -Y 0 (N 2 ) (In the formula, Rf n1 is a perfluoroalkyl group having 1 to 5 carbon atoms, m2 is an integer of 0 to 3, and X n1 is F or CF3, and Y 0is as defined above, a compound represented by the general formula (N 3 ): Rf n2 (CH2) m3 -(Rf n3 ) q -Y 0 (N 3 ) (In the formula, Rf n2 is a partially or fully fluorinated alkyl group having 1 to 13 carbon atoms which may contain an ether bond, m3 is an integer of 1 to 3, and Rf n3 is a linear or branched perfluoroalkylene group having 1 to 3 carbon atoms, q is 0 or 1, and Y 0 is as defined above, a compound represented by the general formula (N 4 ): Rf n4 -O-(CY n1 Y n2 ) p CF2-Y 0 (N 4 ) (In the formula, Rf n4 is a linear or branched partially or fully fluorinated alkyl group having 1 to 12 carbon atoms, which may contain an ether bond and / or a chlorine atom, and Y n1 and Y n2 are the same or different and are H or F, p is 0 or 1, and Y 0 is as defined above, a compound represented by the general formula (N 5 ): [ka] (In the formula, X n2 , X n3 and X n4 Rf may be the same or different and are H, F, or a linear or branched partially or fully fluorinated alkyl group having 1 to 6 carbon atoms, which may contain an ether bond. n5 is a linear or branched partially or fully fluorinated alkylene group having 1 to 3 carbon atoms, which may contain an ether bond; L is a linking group; Y 0 is as defined above, where Xn2 , X n3 , X n4 and Rf n5 The total number of carbon atoms is 18 or less.

[0144] General formula (N 0 ) More specifically, the compounds represented by the general formula (I) include perfluorocarboxylic acids (I), ω-H perfluorocarboxylic acids (II), general formula (III), perfluoroethercarboxylic acids (III), general formula (IV), perfluoroalkyl alkylene carboxylic acids (IV), general formula (V), perfluoroalkoxy fluorocarboxylic acids (V), general formula (VI), perfluoroalkyl sulfonic acids (VI), general formula (VII), ω-H perfluoro sulfonic acids (VII), general formula (VIII), perfluoroalkyl alkylene sulfonic acids (VIII), general formula (IX), alkyl alkylene carboxylic acids (IX), general formula (X), fluorocarboxylic acids (X), general formula (XI), alkoxy fluoro sulfonic acids (XI), general formula (XII), and general formula (XIII).

[0145] The perfluorocarboxylic acid (I) is represented by the general formula (I): F(CF2) n1 COOM (I) (wherein n1 is an integer of 3 to 14, and M is H, a metal atom, or NR 7 4. An optionally substituted imidazolium, an optionally substituted pyridinium, or an optionally substituted phosphonium, wherein R 7 is H or an organic group.

[0146] The ω-H perfluorocarboxylic acid (II) is represented by the general formula (II): H(CF2) n2 COOM (II) (wherein n2 is an integer of 4 to 15, and M is as defined above).

[0147] The perfluoroethercarboxylic acid (III) is represented by the general formula (III): Rf 1 -O-(CF(CF3)CF2O) n3 CF(CF3)COOM (III) (In the formula, Rf 1 is a perfluoroalkyl group having 1 to 5 carbon atoms, n3 is an integer of 0 to 3, and M is as defined above.

[0148] The perfluoroalkyl alkylene carboxylic acid (IV) is represented by the general formula (IV): Rf 2 (CH2) n4 Rf 3 COOM (IV) (In the formula, Rf 2 is a perfluoroalkyl group having 1 to 5 carbon atoms, and Rf 3 is a linear or branched perfluoroalkylene group having 1 to 3 carbon atoms, n4 is an integer of 1 to 3, and M is as defined above.

[0149] The alkoxyfluorocarboxylic acid (V) is represented by the general formula (V): Rf 4 -O-CY 1 Y 2 CF2-COOM (V) (In the formula, Rf 4 is a linear or branched partially or fully fluorinated alkyl group having 1 to 12 carbon atoms, which may contain an ether bond and / or a chlorine atom, and Y 1 and Y 2 are the same or different and are H or F, and M is as defined above.

[0150] The perfluoroalkylsulfonic acid (VI) is represented by the general formula (VI): F(CF2) n5SO3M (VI) (wherein n5 is an integer of 3 to 14, and M is as defined above).

[0151] The ω-H perfluorosulfonic acid (VII) is represented by the general formula (VII): H(CF2) n6 SO3M (VII) (wherein n6 is an integer of 4 to 14, and M is as defined above).

[0152] The perfluoroalkyl alkylene sulfonic acid (VIII) is represented by the general formula (VIII): Rf 5 (CH2) n7 SO3M (VIII) (In the formula, Rf 5 is a perfluoroalkyl group having 1 to 13 carbon atoms, n7 is an integer of 1 to 3, and M is as defined above.

[0153] The alkyl alkylene carboxylic acid (IX) is represented by the general formula (IX): Rf 6 (CH2) n8 COOM (IX) (In the formula, Rf 6 is a linear or branched partially or fully fluorinated alkyl group having 1 to 13 carbon atoms which may contain an ether bond, n8 is an integer from 1 to 3, and M is as defined above.

[0154] The fluorocarboxylic acid (X) is represented by the general formula (X): Rf 7 -O-Rf 8 -O-CF2-COOM (X) (In the formula, Rf 7 is a linear or branched partially or fully fluorinated alkyl group having 1 to 6 carbon atoms, which may contain an ether bond and / or a chlorine atom, and Rf 8is a linear or branched, partially or fully fluorinated alkyl group having 1 to 6 carbon atoms, and M is as defined above.

[0155] The alkoxyfluorosulfonic acid (XI) is represented by the general formula (XI): Rf 9 -O-CY 1 Y 2 CF2-SO3M (XI) (In the formula, Rf 9 is a linear or branched alkyl group having 1 to 12 carbon atoms, which may contain an ether bond, and which may contain chlorine, and which is partially or completely fluorinated; Y 1 and Y 2 are the same or different and are H or F, and M is as defined above.

[0156] The compound (XII) is represented by the general formula (XII): [ka] (In the formula, X 1 , X 2 and X 3 Rf may be the same or different and are H, F, and linear or branched partially or fully fluorinated alkyl groups having 1 to 6 carbon atoms, which may contain ether bonds; 10 is a perfluoroalkylene group having 1 to 3 carbon atoms, L is a linking group, and Y 0 is an anionic group. 0 may be -COOM, -SO2M, or -SO3M, and may be -SO3M or COOM (wherein M is as defined above). Examples of L include a single bond, and a partially or fully fluorinated alkylene group having 1 to 10 carbon atoms which may contain an ether bond.

[0157] The compound (XIII) is represented by the following general formula (XIII): Rf 11 -O-(CF2CF(CF3)O) n9(CF2O) n10 CF2COOM (XIII) (In the formula, Rf 11 is a fluoroalkyl group containing chlorine and having 1 to 5 carbon atoms, n9 is an integer of 0 to 3, n10 is an integer of 0 to 3, and M is as defined above. Compound (XIII) is represented by the formula: CF2ClO(CF2CF(CF3)O) n9 (CF2O) n10 CF2COONH4 (a mixture having an average molecular weight of 750, wherein n9 and n10 are defined above).

[0158] Thus, examples of the anionic fluorine-containing surfactant include carboxylic acid surfactants and sulfonic acid surfactants.

[0159] The fluorine-containing surfactant may be one type of fluorine-containing surfactant or a mixture containing two or more types of fluorine-containing surfactants.

[0160] Examples of the fluorine-containing surfactant include compounds represented by the following formula: The fluorine-containing surfactant may be a mixture of these compounds. F(CF2)7COOM, F(CF2)5COOM, H(CF2)6COOM, H(CF2)7COOM, CF3O(CF2)3OCHFCF2COOM, C3F7OCF(CF3)CF2OCF(CF3)COOM, CF3CF2CF2OCF(CF3)COOM, CF3CF2OCF2CF2OCF2COOM, C2F5OCF(CF3)CF2OCF(CF3)COOM, CF3OCF(CF3)CF2OCF(CF3)COOM, CF2ClCF2CF2OCF(CF3)CF2OCF2COOM, CF2ClCF2CF2OCF2CF(CF3)OCF2COOM, CF2ClCF(CF3)OCF(CF3)CF2OCF2COOM, CF2ClCF(CF3)OCF2CF(CF3)OCF2COOM, and [ka] (In each formula, M is H, metal atom, NR 7 4. An imidazolium which may have a substituent, a pyridinium which may have a substituent, or a phosphonium which may have a substituent. 7 is H or an organic group.

[0161] In each of the above formulas, M is H, a metal atom, or NR 7 4, and may be H, an alkali metal (Group 1), an alkaline earth metal (Group 2), or NR 7 4, which may be H, Na, K, Li, or NH4. R 7 is H or C 1-10 may be an organic group of H or C 1-4 may be an organic group of H or C 1-4 The alkyl group may be:

[0162] The content of the anionic fluorine-containing surfactant is preferably 25 mass ppb or less, more preferably 20 mass ppb or less, even more preferably 15 mass ppb or less, even more preferably 10 mass ppb or less, even more preferably less than 10 mass ppb, even more preferably 1 mass ppb or less, even more preferably less than 1 mass ppb, and particularly preferably less than the lower limit of quantitation, relative to the TFE-based polymer composition. The lower limit is not particularly limited, and may be an amount less than the lower limit of quantitation.

[0163] The amount of the anionic fluorine-containing surfactant is measured by the following method. Weigh out 1 g of sample, add 10 g (12.6 ml) of methanol, and ultrasonicate for 60 minutes to obtain an extract. The resulting extract is concentrated using an appropriate nitrogen purge, and the fluorine-containing compounds in the concentrated extract are measured by LC / MS / MS. Molecular weight information is extracted from the obtained LC / MS spectrum, and a match with the structural formula of the candidate fluorine-containing compound is confirmed. Aqueous solutions with five or more levels of standard substance content are prepared, and LC / MS analysis is performed on each solution. The relationship between content and area relative to that content is plotted, and a calibration curve is drawn. Using the above calibration curve, the area of ​​the LC / MS chromatogram of the fluorine-containing compounds in the extract is converted to the content of the fluorine-containing compounds. The lower limit of quantification in this measurement method is 10 ppb by mass.

[0164] The TFE polymer composition containing an anionic fluorine-containing surfactant can be obtained, for example, by polymerization using an anionic fluorine-containing surfactant.

[0165] The above-mentioned fluorine-containing compound having a hydrophilic group and a molecular weight of 1000 or less also includes a compound represented by the following general formula (1) (hereinafter also referred to as compound (1)). General formula (1):(H-(CF2) m-1 -COO) p M 1 (wherein m is 4 to 20. M 1 is H, metal atom, NR 5 4(R 5 may be the same or different and are H or an organic group having 1 to 10 carbon atoms), imidazolium which may have a substituent, pyridinium which may have a substituent, or phosphonium which may have a substituent. p is 1 or 2.

[0166] M 1 Examples of the metal atom as the metal atom include monovalent and divalent metal atoms, such as alkali metals (Group 1) or alkaline earth metals (Group 2), and specific examples include Na, K, and Li. The Four Rs 5 may be the same or different.5 is preferably H or an organic group having 1 to 10 carbon atoms, more preferably H or an organic group having 1 to 4 carbon atoms.

[0167] In general formula (1), m is preferably 6 or more, more preferably 8 or more, even more preferably 11 or more, even more preferably 13 or more, particularly preferably 15 or more, and is preferably 18 or less, more preferably 16 or less.

[0168] The TFE polymer composition (1) of the present disclosure may contain one or more types of compound (1), but may also contain two or more types, or may also contain three or more types.

[0169] The content of compound (1) (the content of each component when two or more types are present) relative to the TFE-based polymer may be 10 ppm by mass or less, preferably 5,000 ppb by mass or less, more preferably 1,000 ppb by mass or less, even more preferably 500 ppb by mass or less, even more preferably 100 ppb by mass or less, even more preferably 50 ppb by mass or less, even more preferably 25 ppb by mass or less, and particularly preferably 10 ppb by mass or less. The lower limit is not particularly limited, but may be 0.1 mass ppb or 1 mass ppb.

[0170] The above-mentioned fluorine-containing compound having a hydrophilic group and a molecular weight of 1000 or less also includes a compound represented by the following general formula (2) (hereinafter also referred to as compound (2)). General formula (2):(H-(CF2) n -SO3) q M 2 (wherein n is 4 to 20. M 2 is H, metal atom, NR 5 4(R 5 is the same as above), optionally substituted imidazolium, optionally substituted pyridinium, or optionally substituted phosphonium. q is 1 or 2.

[0171] M 2 Examples of the metal atom as the metal atom include monovalent and divalent metal atoms, such as alkali metals (Group 1) or alkaline earth metals (Group 2), and specific examples include Na, K, and Li. The Four Rs 5 may be the same or different. 5 is preferably H or an organic group having 1 to 10 carbon atoms, more preferably H or an organic group having 1 to 4 carbon atoms.

[0172] In general formula (2), n is preferably 6 or more, more preferably 8 or more, even more preferably 11 or more, even more preferably 13 or more, particularly preferably 15 or more, and is preferably 18 or less, more preferably 16 or less.

[0173] The TFE polymer composition (1) of the present disclosure may contain one or more types of compound (2), but may also contain two or more types, or may also contain three or more types.

[0174] The content of compound (2) (content of each component when two or more types are present) may be 10 ppm by mass or less relative to the TFE-based polymer, preferably 5000 ppb by mass or less, more preferably 1000 ppb by mass or less, even more preferably 500 ppb by mass or less, even more preferably 100 ppb by mass or less, even more preferably 50 ppb by mass or less, even more preferably 25 ppb by mass or less, even more preferably 10 ppb by mass or less, even more preferably 1 ppb by mass or less, even more preferably less than 1 ppb by mass, and particularly preferably less than the lower limit of quantitation. The lower limit is not particularly limited, and may be an amount less than the lower limit of quantitation.

[0175] The TFE polymer composition containing the compound (1) and / or (2) can be obtained by using a hydrocarbon surfactant. The TFE polymer composition (1) of the present disclosure may contain a hydrocarbon surfactant in addition to the TFE polymer and the compound (1) and / or (2). The content of the hydrocarbon surfactant in the TFE polymer composition is not particularly limited, but is usually 100 ppm by mass to 10% by mass. In the hydrocarbon surfactant, the proportion of hydrogen atoms bonded to carbon atoms that are substituted with fluorine atoms is preferably 50% or less, more preferably 25% or less, even more preferably 10% or less, and most preferably 0% (no substitution with fluorine atoms at all).

[0176] The TFE polymer composition (1) of the present disclosure preferably contains the compound (1) and / or (2), and is preferably obtained by polymerization using a hydrocarbon surfactant.

[0177] The TFE polymer composition (1) of the present disclosure preferably does not substantially contain a compound represented by the following general formula (3) (hereinafter also referred to as compound (3)). General formula (3): (H-(CF2)8-SO3) q M 2 (In the formula, M 2 is H, metal atom, NR 5 4(R 5 may be the same or different and are H, an organic group having 1 to 10 carbon atoms (preferably an organic group not containing fluorine), an imidazolium which may have a substituent, a pyridinium which may have a substituent, or a phosphonium which may have a substituent. q is 1 or 2.

[0178] "Substantially free of compound (3)" means that the content of compound (3) is 25 mass ppb or less relative to the TFE-based polymer. The content of compound (3) is preferably 20 mass ppb or less, more preferably 15 mass ppb or less, and even more preferably 10 mass ppb or less relative to the TFE-based polymer. The lower limit is not particularly limited, but may be 0 mass ppb, 0.1 mass ppb, or 1 mass ppb.

[0179] The contents of compounds (1), (2) and (3) are values ​​measured by liquid chromatography mass spectrometry as described in the Examples below.

[0180] The TFE polymer composition (1) of the present disclosure is preferably substantially free of water. This can suppress gas generation and deterioration of electrochemical device properties. Furthermore, it is advantageous in terms of production processes because a wide range of electrode active materials and solid electrolytes can be selected for combination. Being substantially free of water means that the water content of the TFE polymer composition is 0.010% by mass or less. The water content is preferably 0.005% by mass or less, more preferably 0.003% by mass or less, even more preferably 0.002% by mass or less, and even more preferably 0.001% by mass or less. The water content is measured by the following method. The mass of the TFE-based polymer composition is measured before and after heating at 150°C for 2 hours, and calculated according to the following formula: A sample is taken three times, and after calculation for each, the average value is calculated and adopted. Water content (mass%)=[(mass (g) of TFE-based polymer composition before heating)−(mass (g) of TFE-based polymer composition after heating)] / (mass (g) of TFE-based polymer composition before heating)×100

[0181] The TFE polymer composition (1) of the present disclosure has fibrillation ability, which refers to the property of easily fiberizing and forming fibrils by shear force. Since a TFE-based polymer composition having fibrillation ability can be paste-extruded, and a TFE-based polymer composition not having fibrillation ability cannot be paste-extruded, whether a TFE-based polymer composition has fibrillation ability can be determined based on whether the composition is paste-extrudable. Specifically, the determination is made in the following manner. 60 g of the TFE-based polymer composition and 12.3 g of hydrocarbon oil (trade name: Isopar G (registered trademark), manufactured by ExxonMobil Corporation) serving as an extrusion aid were mixed in a polyethylene container for 3 minutes. The mixture was filled into the cylinder of an extruder at room temperature (25±2°C), and a load of 0.47 MPa was applied to the piston inserted into the cylinder and maintained for 1 minute. The mixture was then extruded through the orifice at a ram speed of 20 mm / min. The ratio of the cross-sectional area of ​​the cylinder to the cross-sectional area of ​​the orifice was 100. If the beads broke and could not be continuously extruded, it was determined that there was no fibrillation ability (paste extrusion was not possible); if the beads could be continuously extruded without breaking, it was determined that there was fibrillation ability (paste extrusion was possible).

[0182] The TFE-based polymer composition (1) of the present disclosure is preferably non-melt processable.

[0183] The TFE-based polymer composition (1) of the present disclosure may have a 1.0% mass loss temperature of 492°C or lower. A TFE polymer composition having a 1.0% mass loss temperature of 492° C. or less can be obtained by using a hydrocarbon surfactant. The 1.0% mass loss temperature is a value measured by the following method. Approximately 10 mg of a TFE-based polymer composition that has not been heated to temperatures above 300°C is weighed out and placed in a special aluminum pan for measurement using a TG / DTA (thermogravimetric and differential thermal analyzer). The 1.0% mass loss temperature is determined as the temperature at which a 1.0 mass% weight loss occurs when the aluminum pan is heated in an air atmosphere from 25°C to 600°C at a rate of 10°C / min.

[0184] The TFE-based polymer composition (1) of the present disclosure may have a thermal stability index (TII) of 20 or more. A TFE polymer composition having a TII of 20 or more can be obtained by using a hydrocarbon surfactant. The TII is preferably 25 or more, more preferably 30 or more, even more preferably 35 or more, and particularly preferably 40 or more. The TII is also preferably 50 or less. The TII is measured in accordance with ASTM D 4895-89.

[0185] The TFE polymer composition (1) of the present disclosure has an endothermic peak temperature of preferably 327°C or higher, more preferably 330°C or higher, even more preferably 333°C or higher, even more preferably 335°C or higher, even more preferably 337°C or higher, particularly preferably 340°C or higher, and preferably 350°C or lower, more preferably 346°C or lower, in order to form a composite sheet having even greater strength. The endothermic peak temperature is the temperature corresponding to the minimum point in the heat of fusion curve obtained by performing differential scanning calorimetry (DSC) at a heating rate of 10°C / min on a TFE-based polymer composition that has not been heated to a temperature of 300°C or higher. When there are two or more minimum points in one melting peak, each of them is regarded as an endothermic peak temperature.

[0186] The TFE polymer composition (1) of the present disclosure has a melting point of preferably 315°C or higher, more preferably 320°C or higher, even more preferably 323°C or higher, and even more preferably 325°C or higher, in order to form a composite sheet having even greater strength, and preferably 335°C or lower, more preferably 330°C or lower. The melting point is the temperature corresponding to the minimum point in the heat of fusion curve obtained by subjecting a TFE-based polymer composition that has been heated to a temperature of 300°C or higher to differential scanning calorimetry (DSC) at a heating rate of 10°C / min.

[0187] The TFE-based polymer composition (1) of the present disclosure preferably has a standard specific gravity (SSG) of 2.280 or less, more preferably 2.250 or less, even more preferably 2.220 or less, even more preferably 2.200 or less, even more preferably 2.190 or less, especially preferably 2.180 or less, and particularly preferably 2.170 or less, in order to form a composite sheet having even greater strength. The SSG is also preferably 2.130 or more. The SSG is measured by the water displacement method according to ASTM D 792 using a sample molded according to ASTM D 4895 89.

[0188] The TFE polymer composition (1) of the present disclosure may have an average secondary particle size of 350 μm or more, preferably 400 μm or more, and more preferably 450 μm or more, and is preferably 1000 μm or less, more preferably 900 μm or less, even more preferably 800 μm or less, still more preferably 700 μm or less, and particularly preferably 600 μm or less. The average secondary particle diameter is measured in accordance with JIS K 6891.

[0189] The TFE polymer composition (1) of the present disclosure preferably has an apparent density of 0.40 g / ml or more, more preferably 0.43 g / ml or more, from the viewpoint of excellent handleability. The upper limit is not particularly limited, but may be 0.70 g / ml. The apparent density is measured in accordance with JIS K 6892.

[0190] The form of the TFE polymer composition (1) of the present disclosure is not limited, but is preferably a powder, since it can be mixed with an electrode active material and a solid electrolyte without using a large amount of a dispersion medium. The TFE polymer composition may be in a form other than a powder, for example, a dispersion.

[0191] The TFE polymer composition (1) of the present disclosure can be suitably produced, for example, by a production method including a step (A) of preparing an aqueous dispersion of a TFE polymer, a step (B) of coagulating the aqueous dispersion to obtain a wet powder, and a step (C) of drying the wet powder.

[0192] The step (A) is preferably, for example, a step (A1) of obtaining an aqueous dispersion of a TFE-based polymer by emulsion polymerizing TFE and a monomer having a polar group in an aqueous medium in the presence of an anionic fluorine-containing surfactant.

[0193] The emulsion polymerization in step (A1) can be carried out by a known method. For example, an aqueous dispersion containing particles (primary particles) of the TFE-based polymer can be obtained by emulsion polymerization of monomers necessary for constituting the TFE-based polymer in an aqueous medium in the presence of an anionic fluorine-containing surfactant and a polymerization initiator. In the emulsion polymerization, a chain transfer agent, a buffer, a pH adjuster, a stabilizing aid, a dispersion stabilizer, a radical scavenger, etc. may be used as necessary.

[0194] The emulsion polymerization can be carried out, for example, in an aqueous medium in the presence of an anionic fluorine-containing surfactant and a polymerization initiator. The emulsion polymerization can be carried out by charging an aqueous medium, the anionic fluorine-containing surfactant, monomers, and other additives as necessary into a polymerization reactor, stirring the contents of the reactor, maintaining the reactor at a predetermined polymerization temperature, and then adding a predetermined amount of polymerization initiator to initiate the polymerization reaction. After the start of the polymerization reaction, monomers, polymerization initiator, chain transfer agent, the surfactant, etc. may be additionally added depending on the purpose.

[0195] The polymerization initiator is not particularly limited as long as it can generate radicals within the polymerization temperature range, and known oil-soluble and / or water-soluble polymerization initiators can be used. Furthermore, polymerization can also be initiated as a redox reaction in combination with a reducing agent or the like. The concentration of the polymerization initiator is determined appropriately depending on the type of monomer, the molecular weight of the target TFE-based polymer, and the reaction rate.

[0196] As the polymerization initiator, an oil-soluble radical polymerization initiator or a water-soluble radical polymerization initiator can be used.

[0197] The oil-soluble radical polymerization initiator may be a known oil-soluble peroxide, for example, dialkyl peroxycarbonates such as diisopropyl peroxydicarbonate and di-sec-butyl peroxydicarbonate, peroxyesters such as t-butyl peroxyisobutyrate and t-butyl peroxypivalate, dialkyl peroxides such as di-t-butyl peroxide, and the like. Also usable are di(ω-hydro-dodecafluoroheptanoyl) peroxide, di(ω-hydro-tetradecafluoroheptanoyl) peroxide, di(ω-hydro-hexadecafluorononanoyl) peroxide, di(perfluorobutyryl) peroxide, di(perfluorovaleryl) peroxide, di(perfluorohexanoyl) peroxide, di(perfluoroheptanoyl) peroxide, di(perfluorooctanoyl) peroxide, di(perfluorononanoyl) peroxide, di(ω-chloro Representative examples include di[perfluoro(or fluorochloro)acyl]peroxides such as di(ω-hexafluorobutyryl)peroxide, di(ω-chloro-decafluorohexanoyl)peroxide, di(ω-chloro-tetradecafluorooctanoyl)peroxide, ω-hydro-dodecafluoroheptanoyl-ω-hydrohexadecafluorononanoyl-peroxide, ω-chloro-hexafluorobutyryl-ω-chloro-decafluorohexanoyl-peroxide, ω-hydrododecafluoroheptanoyl-perfluorobutyryl-peroxide, di(dichloropentafluorobutanoyl)peroxide, di(trichlorooctafluorohexanoyl)peroxide, di(tetrachloroundecafluorooctanoyl)peroxide, di(pentachlorotetradecafluorodecanoyl)peroxide, and di(undecachlorodotriacontafluorodocosanoyl)peroxide.

[0198] The water-soluble radical polymerization initiator may be a known water-soluble peroxide, such as ammonium salts, potassium salts, or sodium salts of persulfuric acid, perborate, perchloric acid, perphosphoric acid, or percarbonate, t-butyl permaleate, t-butyl hydroperoxide, or disuccinic acid peroxide. Among these, ammonium persulfate and disuccinic acid peroxide are preferred. A reducing agent such as sulfites or sulfites may also be contained, and the amount used may be 0.1 to 20 times the amount of the peroxide.

[0199] The amount of the water-soluble radical polymerization initiator to be added is not particularly limited, but may be added all at once, stepwise, or continuously at the beginning of the polymerization in an amount (for example, several ppm relative to the water concentration) that does not significantly decrease the polymerization rate. The upper limit is a range in which the reaction temperature can be increased while removing heat from the equipment using the heat of polymerization reaction, and a more preferred upper limit is a range in which the heat of polymerization reaction can be removed from the equipment. In terms of easily obtaining the above-mentioned physical properties, the amount of the polymerization initiator added is preferably an amount corresponding to 0.1 ppm or more, more preferably an amount corresponding to 1.0 ppm or more, and is preferably an amount corresponding to 100 ppm or less, more preferably an amount corresponding to 10 ppm or less, relative to the aqueous medium.

[0200] For example, when polymerization is carried out at low temperatures below 30°C, it is preferable to use a redox initiator, which combines an oxidizing agent and a reducing agent, as the polymerization initiator. Examples of oxidizing agents include persulfates, organic peroxides, potassium permanganate, manganese triacetate, cerium ammonium nitrate, and bromates. Examples of reducing agents include sulfites, bisulfites, bromates, diimines, and oxalic acid. Examples of persulfates include ammonium persulfate and potassium persulfate. Examples of sulfites include sodium sulfite and ammonium sulfite. To increase the decomposition rate of the initiator, it is also preferable to add a copper salt or an iron salt to the redox initiator combination. Examples of copper salts include copper(II) sulfate, and examples of iron salts include iron(II) sulfate.

[0201] As the redox initiator, it is preferred that the oxidizing agent is permanganic acid or a salt thereof, a persulfate, manganese triacetate, a cerium (IV) salt, or bromic acid or a salt thereof, and the reducing agent is a dicarboxylic acid or a salt thereof, or a diimine. More preferably, the oxidizing agent is permanganic acid or a salt thereof, persulfate, or bromic acid or a salt thereof, and the reducing agent is a dicarboxylic acid or a salt thereof.

[0202] Examples of the redox initiator include combinations of potassium permanganate / oxalic acid, potassium permanganate / ammonium oxalate, manganese triacetate / oxalic acid, manganese triacetate / ammonium oxalate, cerium ammonium nitrate / oxalic acid, and cerium ammonium nitrate / ammonium oxalate. When a redox initiator is used, either the oxidizing agent or the reducing agent may be charged into a polymerization vessel in advance, and then the other may be added continuously or intermittently to initiate polymerization. For example, when potassium permanganate / oxalic acid is used, it is preferable to charge oxalic acid into a polymerization vessel and then continuously add potassium permanganate thereto. In this specification, when the redox initiator is described as "potassium permanganate / oxalic acid," it means a combination of potassium permanganate and oxalic acid. The same applies to other compounds.

[0203] The redox initiator is particularly preferably a combination of an oxidizing agent that is a salt and a reducing agent that is a salt. For example, the oxidizing agent that is the salt is more preferably at least one selected from the group consisting of persulfates, permanganates, cerium (IV) salts, and bromates, further preferably permanganates, and particularly preferably potassium permanganate. Furthermore, the reducing agent which is the salt is more preferably at least one selected from the group consisting of oxalate, malonate, succinate, glutarate and bromate, further preferably oxalate, and particularly preferably ammonium oxalate.

[0204] Specifically, the redox initiator is preferably at least one selected from the group consisting of potassium permanganate / oxalic acid, potassium permanganate / ammonium oxalate, potassium bromate / ammonium sulfite, manganese triacetate / ammonium oxalate, and cerium ammonium nitrate / ammonium oxalate, more preferably at least one selected from the group consisting of potassium permanganate / oxalic acid, potassium permanganate / ammonium oxalate, potassium bromate / ammonium sulfite, and cerium ammonium nitrate / ammonium oxalate, and even more preferably potassium permanganate / oxalic acid.

[0205] When a redox initiator is used, the oxidizing agent and the reducing agent may be added all at once at the beginning of the polymerization, or the reducing agent may be added all at once at the beginning of the polymerization and the oxidizing agent may be added continuously, or the oxidizing agent may be added all at once at the beginning of the polymerization and the reducing agent may be added continuously, or both the oxidizing agent and the reducing agent may be added continuously.

[0206] When one of the redox polymerization initiators is added at the beginning of the polymerization and the other is added continuously, the rate of addition is preferably gradually reduced in order to obtain a TFE-based polymer having a low SSG, and further, the addition is preferably stopped midway through the polymerization, preferably before 20 to 40% by mass of the total TFE consumed in the polymerization reaction is consumed.

[0207] When a redox initiator is used as a polymerization initiator, the amount of oxidizing agent added to the aqueous medium is preferably 0.1 ppm or more, more preferably 0.3 ppm or more, even more preferably 0.5 ppm or more, even more preferably 1 ppm or more, particularly preferably 5 ppm or more, particularly preferably 10 ppm or more, and preferably 10,000 ppm or less, more preferably 1,000 ppm or less, even more preferably 100 ppm or less, and even more preferably 50 ppm or less. The amount of reducing agent added is preferably 0.1 ppm or more, more preferably 1.0 ppm or more, even more preferably 3 ppm or more, even more preferably 5 ppm or more, particularly preferably 10 ppm or more, and preferably 10,000 ppm or less, more preferably 1,000 ppm or less, even more preferably 100 ppm or less, and even more preferably 50 ppm or less. When a redox initiator is used in the emulsion polymerization, the polymerization temperature is preferably 100° C. or lower, more preferably 95° C. or lower, and even more preferably 90° C. or lower. The polymerization temperature is preferably 10° C. or higher, more preferably 20° C. or higher, and even more preferably 30° C. or higher.

[0208] As the polymerization initiator, a water-soluble radical polymerization initiator and a redox initiator are preferred, since the above-mentioned properties can be easily obtained.

[0209] The aqueous medium is a reaction medium for polymerization and refers to a liquid containing water. The aqueous medium is not particularly limited as long as it contains water, and may contain water and, for example, a fluorine-free organic solvent such as an alcohol, ether, or ketone, and / or a fluorine-containing organic solvent having a boiling point of 40° C. or lower.

[0210] In the emulsion polymerization, a nucleating agent, a chain transfer agent, a buffer, a pH adjuster, a stabilizing aid, a dispersion stabilizer, a radical scavenger, a decomposing agent for the polymerization initiator, a dicarboxylic acid, etc. may be used, if necessary.

[0211] The emulsion polymerization is preferably carried out with the addition of a nucleating agent for the purpose of adjusting the particle size, and the nucleating agent is preferably added before the start of the polymerization reaction. As the nucleating agent, known agents can be used, and for example, at least one selected from the group consisting of fluoropolyethers, nonionic surfactants, and chain transfer agents is preferred, and a nonionic surfactant is more preferred.

[0212] The fluoropolyether may, for example, be a perfluoropolyether (PFPE) acid or a salt thereof. The perfluoropolyether (PFPE) acid or salt thereof may have any chain structure in which oxygen atoms in the main chain of the molecule are separated by saturated fluorocarbon groups having 1 to 3 carbon atoms. Two or more types of fluorocarbon groups may be present in the molecule. A typical structure has a repeating unit represented by the following formula: (-CFCF3-CF2-O-) n (-CF2-CF2-CF2-O-) n (-CF2-CF2-O-) n -(-CF2-O-) m (-CF2-CFCF3-O-) n -(-CF2-O-) m

[0213] These structures are described by Kasai in J. Appl. Polymer Sci. 57, 797 (1995). As disclosed therein, the PFPE acid or its salt may have a carboxylic acid group or a salt thereof at one or both ends. The PFPE acid or its salt may also have a sulfonic acid or phosphonic acid group or a salt thereof at one or both ends. The PFPE acid or its salt may also have a different group at each end. For monofunctional PFPEs, the other end of the molecule is usually perfluorinated but may contain a hydrogen or chlorine atom. The PFPE acid or its salt has at least two ether oxygens, preferably at least four ether oxygens, and even more preferably at least six ether oxygens. Preferably, at least one of the fluorocarbon groups separating the ether oxygens, more preferably at least two of such fluorocarbon groups, has 2 or 3 carbon atoms. Even more preferably, at least 50% of the fluorocarbon groups separating the ether oxygens have 2 or 3 carbon atoms. Also preferably, the PFPE acid or salt thereof has a total of at least 15 carbon atoms, for example, the preferred minimum value of n or n+m in the repeating unit structure above is at least 5. Two or more of the PFPE acids or salts thereof having acid groups at one or both termini can be used in the manufacturing method of the present disclosure. The PFPE acid or salt thereof preferably has a number average molecular weight of less than 6000 g / mol.

[0214] The emulsion polymerization is preferably carried out with the addition of a radical scavenger or a decomposer for the polymerization initiator, since this allows the TFE polymer to have a higher molecular weight and improves the strength of the mixture sheet.The radical scavenger or decomposer for the polymerization initiator is preferably added after the start of the polymerization reaction, preferably before 10% by mass or more, preferably 20% by mass or more of the total TFE consumed in the polymerization reaction is polymerized, and preferably before 50% by mass or less, preferably 40% by mass or less is polymerized.When depressurization and repressurization are performed as described below, it is preferable to add it after that.

[0215] The radical scavenger is a compound that does not have the ability to restart after addition or chain transfer to a free radical in the polymerization system. Specifically, a compound that easily undergoes a chain transfer reaction with a primary radical or a propagating radical to generate a stable radical that does not subsequently react with the monomer, or a compound that easily undergoes an addition reaction with a primary radical or a propagating radical to generate a stable radical, is used. Generally, the activity of what is called a chain transfer agent is characterized by the chain transfer constant and the reinitiation efficiency, but among chain transfer agents, those with a reinitiation efficiency of almost 0% are called radical scavengers. The radical scavenger can also be described as a compound whose chain transfer constant with TFE at the polymerization temperature is greater than the polymerization rate constant and whose reinitiation efficiency is substantially zero percent. "Reinitiation efficiency is substantially zero percent" means that the generated radicals turn the radical scavenger into stable radicals. Preferably, the compound has a chain transfer constant (Cs) with TFE at the polymerization temperature (=chain transfer rate constant (kc) / polymerization rate constant (kp)) of more than 0.1, and the compound has a chain transfer constant (Cs) of more preferably 0.5 or more, even more preferably 1.0 or more, even more preferably 5.0 or more, and particularly preferably 10 or more.

[0216] The radical scavenger is preferably at least one selected from the group consisting of, for example, aromatic hydroxy compounds, aromatic amines, N,N-diethylhydroxylamine, quinone compounds, terpenes, thiocyanates, and cupric chloride (CuCl). Examples of aromatic hydroxy compounds include unsubstituted phenol, polyhydric phenol, salicylic acid, m- or p-salicylic acid, gallic acid, and naphthol. Examples of the unsubstituted phenol include o-, m-, or p-nitrophenol, o-, m-, or p-aminophenol, p-nitrosophenol, etc. Examples of the polyhydric phenol include catechol, resorcinol, hydroquinone, pyrogallol, phloroglucinol, naphthresorcinol, etc. Examples of aromatic amines include o-, m-, or p-phenylenediamine, benzidine, and the like. Examples of the quinone compound include o-, m-, or p-benzoquinone, 1,4-naphthoquinone, and alizarin. Examples of thiocyanates include ammonium thiocyanate (NH4SCN), potassium thiocyanate (KSCN), and sodium thiocyanate (NaSCN). Of the above radical scavengers, aromatic hydroxy compounds are preferred, unsubstituted phenols or polyhydric phenols are more preferred, and hydroquinone is even more preferred.

[0217] The amount of the radical scavenger added is preferably an amount equivalent to 3 to 500% (molar basis) of the polymerization initiator concentration, from the viewpoint of appropriately reducing the standard specific gravity. A more preferred lower limit is 10% (molar basis), and even more preferred is 15% (molar basis). A more preferred upper limit is 400% (molar basis), and even more preferred is 300% (molar basis).

[0218] The polymerization initiator decomposer may be any compound capable of decomposing the polymerization initiator used, and is preferably at least one selected from the group consisting of sulfites, bisulfites, bromates, diimines, diimine salts, oxalic acid, oxalates, copper salts, and iron salts. Examples of sulfites include sodium sulfite and ammonium sulfite. Examples of copper salts include copper(II) sulfate, and examples of iron salts include iron(II) sulfate. The amount of the decomposing agent added is preferably an amount equivalent to 3 to 500% (molar basis) of the initiator concentration, from the viewpoint of appropriately reducing the standard specific gravity. A more preferred lower limit is 10% (molar basis), and even more preferred is 15% (molar basis). A more preferred upper limit is 400% (molar basis), and even more preferred is 300% (molar basis).

[0219] The emulsion polymerization may be carried out in the presence of 5 to 500 ppm of dicarboxylic acid relative to the aqueous medium, preferably 10 to 200 ppm, in order to reduce the amount of coagulation produced during polymerization. If the amount of dicarboxylic acid relative to the aqueous medium is too small, sufficient effects may not be obtained, while if the amount is too large, a chain transfer reaction may occur, resulting in a low molecular weight polymer. The amount of dicarboxylic acid is more preferably 150 ppm or less. The dicarboxylic acid may be added before the start of the polymerization reaction or during the polymerization.

[0220] The dicarboxylic acid is preferably, for example, one represented by the general formula: HOOCRCOOH (wherein R represents an alkylene group having 1 to 5 carbon atoms), more preferably succinic acid, malonic acid, glutaric acid, adipic acid, or pimelic acid, and even more preferably succinic acid.

[0221] In the emulsion polymerization, the polymerization temperature and polymerization pressure are appropriately determined depending on the type of monomer used, the molecular weight of the target TFE polymer, and the reaction rate. Usually, the polymerization temperature is 5 to 150°C, preferably 10°C or higher, more preferably 30°C or higher, and even more preferably 50°C or higher. Also, the polymerization temperature is more preferably 120°C or lower, and even more preferably 100°C or lower. The polymerization pressure is 0.05 to 10 MPaG. The polymerization pressure is more preferably 0.3 MPaG or more, and even more preferably 0.5 MPaG or more. The polymerization pressure is more preferably 5.0 MPaG or less, and even more preferably 3.0 MPaG or less.

[0222] When VDF is used as the modifying monomer, the VDF concentration in the gas in the reactor at the start of polymerization (when the initiator is added) is preferably 0.001 mol% or more, more preferably 0.01 mol% or more, in order to easily obtain the above-mentioned physical properties in the emulsion polymerization. The concentration may also be 15 mol% or less, preferably 6.0 mol% or less, more preferably 5.0 mol% or less, even more preferably 3.0 mol% or less, and particularly preferably 1.0 mol% or less. The VDF concentration may be maintained until the end of the polymerization reaction, or pressure may be released during the reaction. VDF is preferably charged all at once before the start of polymerization, but a portion may be added continuously or intermittently after the start of polymerization.

[0223] When VDF is used as the modifying monomer, it is preferable not to release the pressure in the emulsion polymerization after VDF is charged into the polymerization vessel until the polymerization is completed, which allows VDF to remain in the system until the end of the polymerization, thereby further increasing the strength of the resulting mixture sheet using the TFE-based polymer.

[0224] When HFP is used as the modifying monomer, the HFP concentration in the gas in the reactor at the start of polymerization (when the initiator is added) is preferably 0.01 to 3.0 mol % in the emulsion polymerization, since this facilitates the attainment of the above-mentioned physical properties. Furthermore, the HFP concentration in the gas in the reactor at the time when 40 mass % of the total TFE consumed in the polymerization reaction has been polymerized is preferably greater than 0 mol % and 0.2 mol % or less. The above HFP concentration is preferably maintained thereafter until the end of the polymerization reaction. HFP may be charged all at once before the start of polymerization, or a portion may be charged before the start of polymerization and then added continuously or intermittently after the start of polymerization. By allowing HFP to remain until the end of the polymerization reaction, the extrusion pressure is reduced, despite the high strength of the resulting composite sheet using the TFE-based polymer.

[0225] When HFP is used as the modifying monomer, in the above emulsion polymerization, it is preferable to release the pressure before 5 to 40 mass% of the total TFE consumed in the polymerization reaction is polymerized, and then re-increase the pressure using only TFE, in order to further improve the strength of the resulting mixture sheet using the TFE-based polymer. The pressure reduction is preferably carried out so that the pressure inside the reactor becomes 0.2 MPaG or less, more preferably 0.1 MPaG or less, and even more preferably 0.05 MPaG or less, and is preferably carried out so that the pressure inside the reactor becomes 0.0 MPaG or more. The depressurization and re-increase in pressure may be repeated several times. The depressurization may be carried out until the pressure is reduced using a vacuum pump.

[0226] When CTFE is used as the modifying monomer, in the emulsion polymerization, the CTFE concentration in the gas in the reactor at the start of polymerization (when the initiator is added) is preferably 0.001 mol% or more, more preferably 0.01 mol% or more, since this facilitates the attainment of the above-mentioned physical properties. The concentration is also preferably 3.0 mol% or less, more preferably 1.0 mol% or less. The CTFE concentration may be maintained until the end of the polymerization reaction, or pressure may be released during the reaction. CTFE is preferably charged all at once before the start of polymerization, but a portion may be added continuously or intermittently after the start of polymerization.

[0227] When CTFE is used as the modified monomer, it is preferable not to release the pressure in the emulsion polymerization after the CTFE is charged into the polymerization vessel until the polymerization is completed, which allows the CTFE to remain in the system until the end of the polymerization, and further increases the strength of the resulting mixture sheet using the TFE-based polymer.

[0228] Step (A) is also preferably step (A2) of obtaining an aqueous dispersion of a TFE-based polymer by emulsion polymerization of TFE and a monomer having a polar group in an aqueous medium in the presence of a hydrocarbon-based surfactant.

[0229] In the hydrocarbon surfactant, the proportion of hydrogen atoms bonded to carbon atoms that are substituted with fluorine atoms is preferably 50% or less, more preferably 25% or less, even more preferably 10% or less, and most preferably 0% (no substitution with fluorine atoms at all).

[0230] Step (A2) preferably comprises a step of carrying out emulsion polymerization of tetrafluoroethylene alone, or emulsion polymerization of tetrafluoroethylene and a modified monomer copolymerizable with tetrafluoroethylene, in an aqueous medium in the presence of a specific hydrocarbon surfactant, and a step of continuously adding the specific hydrocarbon surfactant in the above step.

[0231] The continuous addition of a specific hydrocarbon surfactant means, for example, adding the specific hydrocarbon surfactant over time, without interruption, or in portions, rather than all at once. The specific hydrocarbon surfactant is, for example, a hydrocarbon surfactant having one or more carbonyl groups (excluding carbonyl groups in carboxyl groups), or a hydrocarbon surfactant having one or more carbonyl groups (excluding carbonyl groups in carboxyl groups) that has been subjected to radical treatment or oxidation treatment. The radical treatment may be any treatment that generates radicals in a hydrocarbon surfactant having one or more carbonyl groups (excluding carbonyl groups in carboxyl groups). For example, the radical treatment may involve adding deionized water and a hydrocarbon surfactant to a reactor, sealing the reactor, replacing the system with nitrogen, heating and pressurizing the reactor, adding a polymerization initiator, stirring for a certain period of time, and then depressurizing the reactor to atmospheric pressure and cooling. The oxidation treatment is a treatment in which an oxidizing agent is added to a hydrocarbon surfactant having one or more carbonyl groups (excluding carbonyl groups in carboxyl groups). Examples of oxidizing agents include oxygen, ozone, hydrogen peroxide, manganese (IV) oxide, potassium permanganate, potassium dichromate, nitric acid, and sulfur dioxide. The production method described above makes it possible to produce a TFE polymer having a molecular weight equivalent to that of a production method using a conventional fluorine-containing surfactant, without using a conventional fluorine-containing surfactant.

[0232] In the above production method, the step of continuously adding the specific hydrocarbon surfactant preferably starts adding the hydrocarbon surfactant to the aqueous medium when the solid content of the TFE polymer formed in the aqueous medium is less than 0.60% by mass. It is preferable to start adding the specific hydrocarbon surfactant to the aqueous medium when it is 0.5% by mass or less. It is more preferable to start adding the specific hydrocarbon surfactant when the solid content is 0.3% by mass or less, even more preferably when it is 0.2% by mass or less, even more preferably when it is 0.1% by mass or less, and it is particularly preferable to start adding it at the start of polymerization. The solid content is the concentration relative to the total of the aqueous medium and the TFE polymer.

[0233] In the step of continuously adding the specific hydrocarbon surfactant, the amount of the specific hydrocarbon surfactant added is preferably 0.01 to 10% by mass relative to 100% by mass of the aqueous medium, more preferably 0.05% by mass at the lower limit, even more preferably 0.1% by mass at the lower limit, more preferably 5% by mass at the upper limit, and even more preferably 1% by mass at the upper limit.

[0234] In a process for emulsion polymerization of tetrafluoroethylene alone or tetrafluoroethylene and a modified monomer copolymerizable with tetrafluoroethylene in an aqueous medium in the presence of the specific hydrocarbon surfactant, the amount of the specific hydrocarbon surfactant is preferably large, preferably 0.0001 to 10% by mass relative to 100% by mass of the aqueous medium. A more preferred lower limit is 0.001% by mass, and a more preferred upper limit is 1% by mass. If the amount is less than 0.0001% by mass, the dispersion force may be insufficient, while if the amount exceeds 10% by mass, the effect commensurate with the amount may not be obtained, and instead, the polymerization rate may decrease or the reaction may stop. The amount of the specific hydrocarbon surfactant is determined appropriately depending on the type of monomer used, the molecular weight of the target TFE polymer, and other factors.

[0235] The specific hydrocarbon surfactants include those represented by the formula: RX (wherein R is a fluorine-free organic group having 1 to 2000 carbon atoms and one or more carbonyl groups (excluding carbonyl groups in carboxyl groups), and X is -OSOX 1 , -COOX 1 or -SO3X 1 (X 1 is H, metal atom, NR 1 4. An optionally substituted imidazolium, an optionally substituted pyridinium, or an optionally substituted phosphonium, wherein R 1 is H or an organic group (preferably an organic group not containing fluorine), and may be the same or different. )) is preferred. R preferably has 500 or less carbon atoms, more preferably 100 or less, even more preferably 50 or less, and even more preferably 30 or less. The specific hydrocarbon surfactant is a surfactant represented by the following formula (a): [ka] (In the formula, R 1a R is a linear or branched alkyl group having 1 or more carbon atoms or a cyclic alkyl group having 3 or more carbon atoms, in which a hydrogen atom bonded to a carbon atom may be substituted with a monovalent organic group containing a hydroxy group or an ester bond (preferably an organic group not containing fluorine), and when it has 2 or more carbon atoms, it may contain a carbonyl group, and when it has 3 or more carbon atoms, it may contain a monovalent or divalent heterocycle or form a ring. 2a and R 3a R is independently a single bond or a divalent linking group. 1a , R 2a and R 3a X has a total of 6 or more carbon atoms. a is H, metal atom, NR 4a 4. An optionally substituted imidazolium, an optionally substituted pyridinium, or an optionally substituted phosphonium, wherein R 4aR is H or an organic group (preferably an organic group not containing fluorine), and may be the same or different. 1a , R 2a and R 3a Any two of these may be bonded to each other to form a ring.) A surfactant (a) represented by the following formula (b): [ka] (In the formula, R 1b R is a linear or branched alkyl group having 1 or more carbon atoms which may have a substituent, or a cyclic alkyl group having 3 or more carbon atoms which may have a substituent, and when the alkyl group has 3 or more carbon atoms, it may contain a monovalent or divalent heterocycle or form a ring. 2b and R 4b are independently H or a substituent. 3b is an alkylene group having 1 to 10 carbon atoms which may have a substituent. n is an integer of 1 or more. p and q are independently integers of 0 or more. X b is H, metal atom, NR 5b 4. An optionally substituted imidazolium, an optionally substituted pyridinium, or an optionally substituted phosphonium, wherein R 5b R is H or an organic group (preferably an organic group not containing fluorine), and may be the same or different. 1b , R 2b , R 3b and R 4b Any two of may be bonded to each other to form a ring. L is a single bond, -CO2-B-*, -OCO-B-*, -CONR 6b -B-*, -NR 6b CO-B-* or -CO- (However, -CO2-B-, -OCO-B-, -CONR 6b -B-, -NR 6 The carbonyl group contained in CO-B- is excluded.) B is a single bond or an alkylene group having 1 to 10 carbon atoms which may have a substituent, and R 6b represents H or an alkyl group having 1 to 4 carbon atoms which may have a substituent. * represents -OSO3X in the formula. b(b) a surfactant represented by the following formula (c): [ka] (In the formula, R 1c R is a linear or branched alkyl group having 1 or more carbon atoms or a cyclic alkyl group having 3 or more carbon atoms, in which a hydrogen atom bonded to a carbon atom may be substituted with a monovalent organic group containing a hydroxy group or an ester bond (preferably an organic group not containing fluorine), and when it has 2 or more carbon atoms, it may contain a carbonyl group, and when it has 3 or more carbon atoms, it may contain a monovalent or divalent heterocycle or form a ring. 2c and R 3c R is independently a single bond or a divalent linking group. 1c , R 2c and R 3c A has a total of 5 or more carbon atoms. c -COOX c or -SO3X c (X c is H, metal atom, NR 4c 4. An optionally substituted imidazolium, an optionally substituted pyridinium, or an optionally substituted phosphonium, wherein R 4c R is H or an organic group (preferably an organic group not containing fluorine), and may be the same or different. 1c , R 2c and R 3c Any two of these may be bonded to each other to form a ring.) A surfactant (c) represented by the following formula (d): [ka] (In the formula, R 1d R is a linear or branched alkyl group having 1 or more carbon atoms which may have a substituent, or a cyclic alkyl group having 3 or more carbon atoms which may have a substituent, and when the alkyl group has 3 or more carbon atoms, it may contain a monovalent or divalent heterocycle or form a ring. 2d and R 4d are independently H or a substituent. 3dis an alkylene group having 1 to 10 carbon atoms which may have a substituent. n is an integer of 1 or more. p and q are independently integers of 0 or more. A d -SO3X d or -COOX d (X d is H, metal atom, NR 5d 4. An optionally substituted imidazolium, an optionally substituted pyridinium, or an optionally substituted phosphonium, wherein R 5d R is H or an organic group (preferably an organic group not containing fluorine), and may be the same or different. 1d , R 2d , R 3d and R 4d Any two of may be bonded to each other to form a ring. L is a single bond, -CO2-B-*, -OCO-B-*, -CONR 6d -B-*, -NR 6d CO-B-* or -CO- (However, -CO2-B-, -OCO-B-, -CONR 6d -B-, -NR 6d The carbonyl group contained in CO-B- is excluded.) B is a single bond or an alkylene group having 1 to 10 carbon atoms which may have a substituent, and R 6d is H or an alkyl group having 1 to 4 carbon atoms which may have a substituent. * represents A in the formula. d and a surfactant (d) represented by the following formula (e): [ka] (In the formula, R 1e ~R 5e represents H or a monovalent substituent, provided that R 1e and R 3e At least one of the groups has the general formula: -Y e -R 6e a group represented by R 2e and R 5e At least one of the groups has the general formula: -X e -A e or a group represented by the general formula: -Y e -R 6erepresents a group represented by the formula: Also, X e is the same or different in each occurrence and is a divalent linking group or bond; A e may be the same or different in each occurrence, -COOM e , -SO3M e or -OSO3M e (M e is H, metal atom, NR 7e 4. An imidazolium which may have a substituent, a pyridinium which may have a substituent, or a phosphonium which may have a substituent, R 7e is H or an organic group (preferably a fluorine-free organic group); Y e are the same or different in each occurrence, and are -S(=O)2-, -O-, -COO-, -OCO-, -CONR 8e - and -NR 8e a divalent linking group selected from the group consisting of CO—, or a bond, R 8e is H or an organic group (preferably a fluorine-free organic group); R 6e are the same or different in each occurrence and each represents an alkyl group having two or more carbon atoms which may contain at least one group selected from the group consisting of a carbonyl group, an ester group, an amide group and a sulfonyl group between carbon atoms; Represents. R 1e ~R 5e Any two of the groups may be bonded to each other to form a ring.)

[0236] The surfactant (a) will now be described.

[0237] In formula (a), R 1a is a linear or branched alkyl group having 1 or more carbon atoms or a cyclic alkyl group having 3 or more carbon atoms. When the alkyl group has three or more carbon atoms, it may contain a carbonyl group (-C(=O)-) between two carbon atoms. When the alkyl group has two or more carbon atoms, it may also contain the carbonyl group at the terminal of the alkyl group. In other words, acyl groups such as an acetyl group represented by CH3-C(=O)- are also included in the alkyl group. Furthermore, when the alkyl group has 3 or more carbon atoms, it may contain a monovalent or divalent heterocyclic ring or may form a ring. The heterocyclic ring is preferably an unsaturated heterocyclic ring, more preferably an oxygen-containing unsaturated heterocyclic ring, such as a furan ring. 1a In the above, a divalent heterocycle may be inserted between two carbon atoms, a divalent heterocycle may be located at a terminal and bonded to -C(=O)-, or a monovalent heterocycle may be located at the terminal of the alkyl group.

[0238] In this specification, the "number of carbon atoms" of the alkyl group includes the number of carbon atoms constituting the carbonyl group and the number of carbon atoms constituting the heterocycle. For example, a group represented by CH3-C(=O)-CH2- has 3 carbon atoms, a group represented by CH3-C(=O)-C2H4-C(=O)-C2H4- has 7 carbon atoms, and a group represented by CH3-C(=O)- has 2 carbon atoms.

[0239] In the alkyl group, a hydrogen atom bonded to a carbon atom may be substituted with a functional group, for example, with a hydroxy group (—OH) or a monovalent organic group containing an ester bond (preferably an organic group not containing fluorine), but it is preferable that the alkyl group is not substituted with any functional group. The monovalent organic group containing an ester bond is a group represented by the formula: -OC(=O)-R 101a (In the formula, R 101a is an alkyl group). The alkyl group may have 75% or less, 50% or less, or 25% or less of the hydrogen atoms bonded to carbon atoms substituted with halogen atoms, but is preferably a non-halogenated alkyl group that does not contain halogen atoms such as fluorine atoms or chlorine atoms.

[0240] In the formula, R 2a and R 3a are independently a single bond or a divalent linking group. R 2a and R 3a are preferably independently a single bond, a linear or branched alkylene group having one or more carbon atoms, or a cyclic alkylene group having three or more carbon atoms. R 2a and R 3a The alkylene group constituting the formula (I) preferably does not contain a carbonyl group.

[0241] In the alkylene group, a hydrogen atom bonded to a carbon atom may be substituted with a functional group, for example, with a hydroxy group (—OH) or a monovalent organic group containing an ester bond (preferably an organic group not containing fluorine), but it is preferable that the alkylene group is not substituted with any functional group. The monovalent organic group containing an ester bond is a group represented by the formula: -OC(=O)-R 102a (In the formula, R 102a is an alkyl group). The alkylene group may have 75% or less, 50% or less, or 25% or less of the hydrogen atoms bonded to carbon atoms substituted with halogen atoms, but is preferably a non-halogenated alkylene group that does not contain halogen atoms such as fluorine atoms or chlorine atoms.

[0242] R 1a , R 2a and R 3ahas a total carbon number of 6 or more. The total carbon number is preferably 8 or more, more preferably 9 or more, and even more preferably 10 or more, and is preferably 20 or less, more preferably 18 or less, and even more preferably 15 or less. R 1a , R 2a and R 3a Any two of these may be bonded to each other to form a ring.

[0243] In formula (a), X a is H, metal atom, NR 4a 4. An optionally substituted imidazolium, an optionally substituted pyridinium, or an optionally substituted phosphonium, wherein R 4a is H or an organic group (preferably an organic group not containing fluorine). 4a may be the same or different. 4a The organic group in R is preferably an alkyl group. 4a is preferably H or an organic group having 1 to 10 carbon atoms, more preferably H or an organic group having 1 to 4 carbon atoms, and even more preferably H or an alkyl group having 1 to 4 carbon atoms. Examples of the metal atom include alkali metals (Group 1) and alkaline earth metals (Group 2), and Na, K, or Li is preferred. X a H, alkali metals (group 1), alkaline earth metals (group 2) or NR 4a X is preferred, H, Na, K, Li or NH is more preferred because they are easily soluble in water, Na, K or NH is even more preferred because they are even more easily soluble in water, Na or NH is particularly preferred, and NH is most preferred because it is easily removed. a When is NH4, the surfactant has excellent solubility in an aqueous medium, and metal components are less likely to remain in the TFE-based polymer or the final product.

[0244] Examples of surfactant (a) include the following surfactants: a is as described above.

[0245] [ka]

[0246] [ka]

[0247] [ka]

[0248] [ka]

[0249] [ka]

[0250] [ka]

[0251] [ka]

[0252] [ka]

[0253] The surfactant (a) can be produced, for example, by the production method described in WO 2020 / 022355.

[0254] Next, the surfactant (b) will be described.

[0255] In formula (b), R 1b is a linear or branched alkyl group having 1 or more carbon atoms which may have a substituent, or a cyclic alkyl group having 3 or more carbon atoms which may have a substituent. When the alkyl group has 3 or more carbon atoms, it may contain a monovalent or divalent heterocyclic ring or may form a ring. The heterocyclic ring is preferably an unsaturated heterocyclic ring, more preferably an oxygen-containing unsaturated heterocyclic ring, such as a furan ring. 1b In the above, a divalent heterocycle may be inserted between two carbon atoms, a divalent heterocycle may be located at a terminal and bonded to -C(=O)-, or a monovalent heterocycle may be located at the terminal of the alkyl group.

[0256] In this specification, the "number of carbon atoms" of the alkyl group includes the number of carbon atoms constituting the heterocycle.

[0257] R 1b The substituent that the alkyl group may have is preferably a halogen atom, a linear or branched alkyl group having 1 to 10 carbon atoms, a cyclic alkyl group having 3 to 10 carbon atoms, or a hydroxy group, and particularly preferably a methyl group or an ethyl group.

[0258] R 1b The alkyl group as above preferably does not contain a carbonyl group. The alkyl group may have 75% or less, 50% or less, or 25% or less of the hydrogen atoms bonded to carbon atoms substituted with halogen atoms, but is preferably a non-halogenated alkyl group that does not contain halogen atoms such as fluorine atoms or chlorine atoms. The alkyl group preferably does not have any substituents.

[0259] R 1bAs the alkyl group, a linear or branched alkyl group having 1 to 10 carbon atoms which may have a substituent or a cyclic alkyl group having 3 to 10 carbon atoms which may have a substituent is preferred, a linear or branched alkyl group having 1 to 10 carbon atoms which does not contain a carbonyl group or a cyclic alkyl group having 3 to 10 carbon atoms which does not contain a carbonyl group is more preferred, a linear or branched alkyl group having 1 to 10 carbon atoms which does not contain a substituent is even more preferred, a linear or branched alkyl group having 1 to 3 carbon atoms which does not contain a substituent is even more preferred, a methyl group (-CH3) or an ethyl group (-C2H5) is particularly preferred, and a methyl group (-CH3) is most preferred.

[0260] In formula (b), R 2b and R 4b are independently H or a substituent. 2b and R 4b may be the same or different.

[0261] R 2b and R 4b The substituent as is preferably a halogen atom, a linear or branched alkyl group having 1 to 10 carbon atoms, a cyclic alkyl group having 3 to 10 carbon atoms, or a hydroxy group, and particularly preferably a methyl group or an ethyl group.

[0262] R 2b and R 4b The alkyl group as above preferably does not contain a carbonyl group. The alkyl group may have 75% or less, 50% or less, or 25% or less of the hydrogen atoms bonded to carbon atoms substituted with halogen atoms, but is preferably a non-halogenated alkyl group that does not contain halogen atoms such as fluorine atoms or chlorine atoms. The alkyl group preferably does not have any substituents.

[0263] R 2b and R 4bThe alkyl group as the alkyl group is preferably a linear or branched alkyl group having 1 to 10 carbon atoms and not containing a carbonyl group, or a cyclic alkyl group having 3 to 10 carbon atoms and not containing a carbonyl group, more preferably a linear or branched alkyl group having 1 to 10 carbon atoms and not containing a carbonyl group, even more preferably a linear or branched alkyl group having 1 to 3 carbon atoms and not containing a substituent, and particularly preferably a methyl group (-CH3) or an ethyl group (-C2H5).

[0264] R 2b and R 4b are each independently preferably H or a straight-chain or branched-chain alkyl group having 1 to 10 carbon atoms and not containing a carbonyl group, more preferably H or a straight-chain or branched-chain alkyl group having 1 to 3 carbon atoms and not containing a substituent, even more preferably H, a methyl group (-CH3), or an ethyl group (-C2H5), and particularly preferably H.

[0265] In formula (b), R 3b R is an alkylene group having 1 to 10 carbon atoms which may have a substituent. 3b When there are a plurality of, they may be the same or different.

[0266] The alkylene group preferably does not contain a carbonyl group. The alkylene group may have 75% or less, 50% or less, or 25% or less of the hydrogen atoms bonded to carbon atoms substituted with halogen atoms, but is preferably a non-halogenated alkylene group that does not contain halogen atoms such as fluorine atoms or chlorine atoms. The alkylene group preferably does not have any substituents.

[0267] The alkylene group is preferably a linear or branched alkylene group having 1 to 10 carbon atoms which may have a substituent, or a cyclic alkylene group having 3 to 10 carbon atoms which may have a substituent, more preferably a linear or branched alkylene group having 1 to 10 carbon atoms which does not contain a carbonyl group, or a cyclic alkylene group having 3 to 10 carbon atoms which does not contain a carbonyl group, more preferably a linear or branched alkylene group having 1 to 10 carbon atoms which does not have a substituent, and still more preferably a methylene group (-CH2-), an ethylene group (-C2H4-), an isopropylene group (-CH(CH3)CH2-) or a propylene group (-C3H6-).

[0268] R 1b , R 2b , R 3b and R 4b Any two of may be bonded to each other to form a ring, but it is preferable that they do not form a ring.

[0269] In formula (b), n is an integer of 1 or greater. n is preferably an integer of 1 to 40, more preferably an integer of 1 to 30, still more preferably an integer of 5 to 25, and particularly preferably an integer of 5 to 9 or 11 to 25.

[0270] In formula (b), p and q are independently an integer of 0 or greater. p is preferably an integer of 0 to 10, more preferably 0 or 1. q is preferably an integer of 0 to 10, more preferably an integer of 0 to 5.

[0271] The sum of n, p, and q is preferably an integer of 5 or greater. The sum of n, p, and q is more preferably an integer of 8 or greater. The sum of n, p, and q is also preferably an integer of 60 or less, more preferably an integer of 50 or less, and even more preferably an integer of 40 or less.

[0272] In formula (b), X b is H, metal atom, NR 5b 4. An optionally substituted imidazolium, an optionally substituted pyridinium, or an optionally substituted phosphonium, wherein R 5bis H or an organic group (preferably an organic group not containing fluorine). 5b may be the same or different. 5b The organic group in R is preferably an alkyl group. 5b is preferably H or an organic group having 1 to 10 carbon atoms, more preferably H or an organic group having 1 to 4 carbon atoms, and even more preferably H or an alkyl group having 1 to 4 carbon atoms. Examples of the metal atom include alkali metals (Group 1) and alkaline earth metals (Group 2), and Na, K, or Li are preferred. X b is a metal atom or NR 5b 4(R 5b is as above). X b H, alkali metals (group 1), alkaline earth metals (group 2) or NR 5b X is preferred, H, Na, K, Li or NH is more preferred because they are easily soluble in water, Na, K or NH is even more preferred because they are even more easily soluble in water, Na or NH is particularly preferred, and NH is most preferred because it is easily removed. b When is NH4, the surfactant has excellent solubility in an aqueous medium, and metal components are less likely to remain in the TFE-based polymer or the final product.

[0273] In formula (b), L is a single bond, -CO2-B-*, -OCO-B-*, or -CONR 6b -B-*, -NR 6b CO-B-* or -CO- (However, -CO2-B-, -OCO-B-, -CONR 6b -B-, -NR 6b The carbonyl group contained in CO-B- is excluded.) B is a single bond or an alkylene group having 1 to 10 carbon atoms which may have a substituent, and R 6b is H or an alkyl group having 1 to 4 carbon atoms which may have a substituent. The alkylene group preferably has 1 to 5 carbon atoms. 6b is preferably H or a methyl group. * represents -OSO3X in the formula. b This refers to the side that binds to the

[0274] L is preferably a single bond.

[0275] The surfactant (b) may be a compound represented by the following formula: [ka] (In the formula, R 1b , R 2b , L, n and X b is as described above. ) is preferred.

[0276] Examples of the surfactant (b) include: CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Na, CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2OSO3Na, CH3C(O)CH2CH2CH2CH2CH2CH2CH2OSO3Na, CH3C(O)CH2CH2CH2CH2CH2CH2OSO3Na, CH3C(O)CH2CH2CH2CH2CH2OSO3Na, CH3C(O)CH2CH2CH2CH2OSO3Na, (CH3)3CC(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Na, (CH3)2CHC(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Na, (CH2)5CHC(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Na, CH3CH2C(O)CH2CH2CH2CH2CH2CH2CH2CH2OSO3Na, CH3CH2CH2C(O)CH2CH2CH2CH2CH2CH2CH2OSO3Na, CH3CH2CH2CH2C(O)CH2CH2CH2CH2CH2CH2OSO3Na, CH3CH2CH2CH2CH2C(O)CH2CH2CH2CH2CH2OSO3Na, CH3CH2CH2CH2CH2CH2C(O)CH2CH2CH2CH2OSO3Na, CH3CH2CH2CH2CH2CH2CH2C(O)CH2CH2CH2OSO3Naぁ CH3CH2CH2CH2CH2CH2CH2CH2C(O)CH2CH2OSO3Naぁ CH3CH2CH2CH2CH2CH2CH2CH2CH2C(O)CH2OSO3Naぁ CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2OCH2CH2OSO3Naぁ CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2C(O)NHCH2OSO3Na、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2NHC(O)CH2OSO3Na、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2C(O)OSO3Na、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2C(O)OCH2OSO3Na、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2OC(O)CH2OSO3Naぁ CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3H、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Liぁ CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3K、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3NH4、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH(CH3)2OSO3Naぁ CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Naぁ CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Naぁ CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Naぁ CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Naぁ CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Naぁ CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Naぁ CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Naぁ CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Naぁ (CH3)3CC(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Naぁ (CH3)2CHC(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Naぁ (CH2)5CHC(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Naぁ CH3CH2C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Naぁ CH3CH2CH2CH2CH2C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Naぁ CH3CH2CH2CH2CH2CH2CH2CH2C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Naぁ CH3CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2C(O)CH2CH2CH2CH2CH2CH2CH2OSO3Naぁ CH3CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2C(O)CH2CH2CH2CH2OSO3Na, CH3CH2C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OCH2CH2OSO3Na, CH3CH2C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2C(O)NHCH2CH2OSO3Na, CH3CH2C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2NHC(O)CH2CH2OSO3Na, CH3CH2C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2C(O)OCH2CH2OSO3Na, CH3CH2C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OC(O)CH2CH2OSO3Na, CH3CH2C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2C(O)OSO3Na, CH3CH2C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3H, CH3CH2C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Li, CH3CH2C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3K, CH3CH2C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3NH4, CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2OSO3Na and the like can be mentioned.

[0277] The surfactant (b) can be produced, for example, by the production method described in WO 2020 / 022355.

[0278] Next, the surfactant (c) will be described.

[0279] In formula (c), R 1c is a linear or branched alkyl group having 1 or more carbon atoms or a cyclic alkyl group having 3 or more carbon atoms. When the alkyl group has three or more carbon atoms, it may contain a carbonyl group (-C(=O)-) between two carbon atoms. When the alkyl group has two or more carbon atoms, it may also contain the carbonyl group at the terminal of the alkyl group. In other words, acyl groups such as an acetyl group represented by CH3-C(=O)- are also included in the alkyl group. Furthermore, when the alkyl group has 3 or more carbon atoms, it may contain a monovalent or divalent heterocyclic ring or may form a ring. The heterocyclic ring is preferably an unsaturated heterocyclic ring, more preferably an oxygen-containing unsaturated heterocyclic ring, such as a furan ring. 1c In the above, a divalent heterocycle may be inserted between two carbon atoms, a divalent heterocycle may be located at a terminal and bonded to -C(=O)-, or a monovalent heterocycle may be located at the terminal of the alkyl group.

[0280] In this specification, the "number of carbon atoms" of the alkyl group includes the number of carbon atoms constituting the carbonyl group and the number of carbon atoms constituting the heterocycle. For example, a group represented by CH3-C(=O)-CH2- has 3 carbon atoms, a group represented by CH3-C(=O)-C2H4-C(=O)-C2H4- has 7 carbon atoms, and a group represented by CH3-C(=O)- has 2 carbon atoms.

[0281] In the alkyl group, a hydrogen atom bonded to a carbon atom may be substituted with a functional group, for example, with a hydroxy group (—OH) or a monovalent organic group containing an ester bond (preferably an organic group not containing fluorine), but it is preferable that the alkyl group is not substituted with any functional group. The monovalent organic group containing an ester bond is a group represented by the formula: -OC(=O)-R 101c (In the formula, R 101c is an alkyl group). The alkyl group may have 75% or less, 50% or less, or 25% or less of the hydrogen atoms bonded to carbon atoms substituted with halogen atoms, but is preferably a non-halogenated alkyl group that does not contain halogen atoms such as fluorine atoms or chlorine atoms.

[0282] In formula (c), R 2c and R 3c are independently a single bond or a divalent linking group. R 2c and R 3c are preferably independently a single bond, a linear or branched alkylene group having 1 or more carbon atoms, or a cyclic alkylene group having 3 or more carbon atoms. R 2c and R 3c The alkylene group constituting the formula (I) preferably does not contain a carbonyl group.

[0283] In the alkylene group, a hydrogen atom bonded to a carbon atom may be substituted with a functional group, for example, with a hydroxy group (—OH) or a monovalent organic group containing an ester bond (preferably an organic group not containing fluorine), but it is preferable that the alkylene group is not substituted with any functional group. The monovalent organic group containing an ester bond is a group represented by the formula: -OC(=O)-R 102c (In the formula, R 102c is an alkyl group). The alkylene group may have 75% or less, 50% or less, or 25% or less of the hydrogen atoms bonded to carbon atoms substituted with halogen atoms, but is preferably a non-halogenated alkylene group that does not contain halogen atoms such as fluorine atoms or chlorine atoms.

[0284] R 1c , R 2c and R 3c has a total carbon number of 5 or more. The total carbon number is preferably 7 or more, more preferably 9 or more, and is preferably 20 or less, more preferably 18 or less, and even more preferably 15 or less. R 1c , R 2c and R 3c Any two of these may be bonded to each other to form a ring.

[0285] In formula (c), in formula, A c -COOX c or -SO3X c (X c is H, metal atom, NR 4c 4. An optionally substituted imidazolium, an optionally substituted pyridinium, or an optionally substituted phosphonium, wherein R 4c R is H or an organic group (preferably an organic group not containing fluorine), and may be the same or different. 4c The organic group in R is preferably an alkyl group. 4c is preferably H or an organic group having 1 to 10 carbon atoms, more preferably H or an organic group having 1 to 4 carbon atoms, and even more preferably H or an alkyl group having 1 to 4 carbon atoms. Examples of the metal atom include alkali metals (Group 1) and alkaline earth metals (Group 2), and Na, K, or Li is preferred. X c H, alkali metals (group 1), alkaline earth metals (group 2) or NR 4cX is preferred, H, Na, K, Li or NH is more preferred because they are easily soluble in water, Na, K or NH is even more preferred because they are even more easily soluble in water, Na or NH is particularly preferred, and NH is most preferred because it is easily removed. c When is NH4, the surfactant has excellent solubility in an aqueous medium, and metal components are less likely to remain in the TFE-based polymer or the final product.

[0286] Examples of the surfactant (c) include the following surfactants: c is as described above.

[0287] [ka]

[0288] [ka]

[0289] [ka]

[0290] [ka]

[0291] [ka]

[0292] [ka]

[0293] [ka]

[0294] [ka]

[0295] The surfactant (c) can be produced, for example, by the production method described in WO 2020 / 022355.

[0296] Next, the surfactant (d) will be described.

[0297] In formula (d), R 1d is a linear or branched alkyl group having 1 or more carbon atoms which may have a substituent, or a cyclic alkyl group having 3 or more carbon atoms which may have a substituent. When the alkyl group has 3 or more carbon atoms, it may contain a monovalent or divalent heterocyclic ring or may form a ring. The heterocyclic ring is preferably an unsaturated heterocyclic ring, more preferably an oxygen-containing unsaturated heterocyclic ring, such as a furan ring. 1d In the above, a divalent heterocycle may be inserted between two carbon atoms, a divalent heterocycle may be located at a terminal and bonded to -C(=O)-, or a monovalent heterocycle may be located at the terminal of the alkyl group.

[0298] In this specification, the "number of carbon atoms" of the alkyl group includes the number of carbon atoms constituting the heterocycle.

[0299] R 1d The substituent that the alkyl group may have is preferably a halogen atom, a linear or branched alkyl group having 1 to 10 carbon atoms, a cyclic alkyl group having 3 to 10 carbon atoms, or a hydroxy group, and particularly preferably a methyl group or an ethyl group.

[0300] R 1d The alkyl group as above preferably does not contain a carbonyl group. The alkyl group may have 75% or less, 50% or less, or 25% or less of the hydrogen atoms bonded to carbon atoms substituted with halogen atoms, but is preferably a non-halogenated alkyl group that does not contain halogen atoms such as fluorine atoms or chlorine atoms. The alkyl group preferably does not have any substituents.

[0301] R 1d As the alkyl group, a linear or branched alkyl group having 1 to 10 carbon atoms which may have a substituent or a cyclic alkyl group having 3 to 10 carbon atoms which may have a substituent is preferred, a linear or branched alkyl group having 1 to 10 carbon atoms which does not contain a carbonyl group or a cyclic alkyl group having 3 to 10 carbon atoms which does not contain a carbonyl group is more preferred, a linear or branched alkyl group having 1 to 10 carbon atoms which does not contain a substituent is even more preferred, a linear or branched alkyl group having 1 to 3 carbon atoms which does not contain a substituent is even more preferred, a methyl group (-CH3) or an ethyl group (-C2H5) is particularly preferred, and a methyl group (-CH3) is most preferred.

[0302] In formula (d), R 2d and R 4d are independently H or a substituent. 2d and R 4d may be the same or different.

[0303] R 2d and R 4d The substituent as is preferably a halogen atom, a linear or branched alkyl group having 1 to 10 carbon atoms, a cyclic alkyl group having 3 to 10 carbon atoms, or a hydroxy group, and particularly preferably a methyl group or an ethyl group.

[0304] R 2d and R 4d The alkyl group as above preferably does not contain a carbonyl group. The alkyl group may have 75% or less, 50% or less, or 25% or less of the hydrogen atoms bonded to carbon atoms substituted with halogen atoms, but is preferably a non-halogenated alkyl group that does not contain halogen atoms such as fluorine atoms or chlorine atoms. The alkyl group preferably does not have any substituents.

[0305] R 2d and R 4d The alkyl group as the alkyl group is preferably a linear or branched alkyl group having 1 to 10 carbon atoms and not containing a carbonyl group, or a cyclic alkyl group having 3 to 10 carbon atoms and not containing a carbonyl group, more preferably a linear or branched alkyl group having 1 to 10 carbon atoms and not containing a carbonyl group, even more preferably a linear or branched alkyl group having 1 to 3 carbon atoms and not containing a substituent, and particularly preferably a methyl group (-CH3) or an ethyl group (-C2H5).

[0306] R 2d and R 4d are each independently preferably H or a straight-chain or branched-chain alkyl group having 1 to 10 carbon atoms and not containing a carbonyl group, more preferably H or a straight-chain or branched-chain alkyl group having 1 to 3 carbon atoms and not containing a substituent, even more preferably H, a methyl group (-CH3), or an ethyl group (-C2H5), and particularly preferably H.

[0307] In formula (d), R 3d R is an alkylene group having 1 to 10 carbon atoms which may have a substituent. 3d When there are a plurality of, they may be the same or different.

[0308] The alkylene group preferably does not contain a carbonyl group. The alkylene group may have 75% or less, 50% or less, or 25% or less of the hydrogen atoms bonded to carbon atoms substituted with halogen atoms, but is preferably a non-halogenated alkyl group that does not contain halogen atoms such as fluorine atoms or chlorine atoms. The alkylene group preferably does not have any substituents.

[0309] The alkylene group is preferably a linear or branched alkylene group having 1 to 10 carbon atoms which may have a substituent, or a cyclic alkylene group having 3 to 10 carbon atoms which may have a substituent, more preferably a linear or branched alkylene group having 1 to 10 carbon atoms which does not contain a carbonyl group, or a cyclic alkylene group having 3 to 10 carbon atoms which does not contain a carbonyl group, more preferably a linear or branched alkylene group having 1 to 10 carbon atoms which does not have a substituent, and still more preferably a methylene group (-CH2-), an ethylene group (-C2H4-), an isopropylene group (-CH(CH3)CH2-) or a propylene group (-C3H6-).

[0310] R 1d , R 2d , R 3d and R 4d Any two of these may be bonded to each other to form a ring.

[0311] In formula (d), n is an integer of 1 or greater. n is preferably an integer of 1 to 40, more preferably an integer of 1 to 30, and even more preferably an integer of 5 to 25.

[0312] In formula (d), p and q are independently an integer of 0 or greater. p is preferably an integer of 0 to 10, more preferably 0 or 1. q is preferably an integer of 0 to 10, more preferably an integer of 0 to 5.

[0313] The sum of n, p, and q is preferably an integer of 6 or greater. The sum of n, p, and q is more preferably an integer of 8 or greater. The sum of n, p, and q is also preferably an integer of 60 or less, more preferably an integer of 50 or less, and even more preferably an integer of 40 or less.

[0314] In formula (d), A d -SO3X d or -COOX d (X d is H, metal atom, NR 5d 4. An optionally substituted imidazolium, an optionally substituted pyridinium, or an optionally substituted phosphonium, wherein R 5d R is H or an organic group (preferably an organic group not containing fluorine), and may be the same or different. 5d The organic group in R is preferably an alkyl group. 5d is preferably H or an organic group having 1 to 10 carbon atoms, more preferably H or an organic group having 1 to 4 carbon atoms, and even more preferably H or an alkyl group having 1 to 4 carbon atoms. Examples of the metal atom include alkali metals (Group 1) and alkaline earth metals (Group 2), and Na, K, or Li are preferred. X d is a metal atom or NR 5d 4(R 5d is as above). X d H, alkali metals (group 1), alkaline earth metals (group 2) or NR 5d X is preferred, H, Na, K, Li or NH is more preferred because they are easily soluble in water, Na, K or NH is even more preferred because they are even more easily soluble in water, Na or NH is particularly preferred, and NH is most preferred because it is easily removed. d When is NH4, the surfactant has excellent solubility in an aqueous medium, and metal components are less likely to remain in the TFE-based polymer or the final product.

[0315] In formula (d), L is a single bond, -CO2-B-*, -OCO-B-*, or -CONR 6d -B-*, -NR6d CO-B-* or -CO- (However, -CO2-B-, -OCO-B-, -CONR 6d -B-, -NR 6d The carbonyl group contained in CO-B- is excluded.) B is a single bond or an alkylene group having 1 to 10 carbon atoms which may have a substituent, and R 6d is H or an alkyl group having 1 to 4 carbon atoms which may have a substituent. The alkylene group more preferably has 1 to 5 carbon atoms. 6d is more preferably H or a methyl group. d This refers to the side that binds to the

[0316] L is preferably a single bond.

[0317] Examples of the surfactant (d) include: CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2COOK, CH3C(O)CH2CH2CH2CH2CH2CH2CH2COONa, CH3C(O)CH2CH2CH2CH2CH2CH2COONa, CH3C(O)CH2CH2CH2CH2CH2COONa, CH3C(O)CH2CH2CH2CH2COONa, CH3C(O)CH2CH2CH2COONa, CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2COONa, CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2COONa, (CH3)3CC(O)CH2CH2CH2CH2CH2CH2CH2CH2COONa, (CH3)2CHC(O)CH2CH2CH2CH2CH2CH2CH2CH2COONa, (CH2)5CHC(O)CH2CH2CH2CH2CH2CH2CH2CH2COONa, CH3CH2C(O)CH2CH2CH2CH2CH2CH2CH2COONa、 CH3CH2CH2C(O)CH2CH2CH2CH2CH2CH2COONa、 CH3CH2CH2CH2C(O)CH2CH2CH2CH2CH2COONa、 CH3CH2CH2CH2CH2C(O)CH2CH2CH2CH2COONa、 CH3CH2CH2CH2CH2CH2C(O)CH2CH2CH2COONa、 CH3CH2CH2CH2CH2CH2CH2C(O)CH2CH2COONa、 CH3CH2CH2CH2CH2CH2CH2CH2C(O)CH2COONa、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2OCH2CH2COONa、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2C(O)NHCH2COOK、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2NHC(O)CH2COOK、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2C(O)OCH2COONa、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2OC(O)CH2COONa、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2C(O)COONa、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2C(O)COOH、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2C(O)COOLi, CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2C(O)COONH4、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2C(O)COONa、CH3C(O)CH2CH2CH2CH2CH2CH2CH2C(CH3)2COOK、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2SO3Na、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2SO3Naぁ CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2SO3Naぁ CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2CH2SO3Naぁ (CH3)3CC(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2SO3Naぁ (CH3)2CHC(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2SO3Naぁ (CH2)5CHC(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2SO3Naぁ CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2SO3Naぁ CH3C(O)CH2CH2CH2CH2CH2CH2CH2SO3Naぁ CH3C(O)CH2CH2CH2CH2CH2CH2SO3Naぁ CH3C(O)CH2CH2CH2CH2CH2SO3Naぁ CH3C(O)CH2CH2CH2CH2SO3Naぁ CH3C(O)CH2CH2CH2SO3Naぁ CH3C(O)CH2CH2SO3Naぁ CH3C(O)CH2SO3Naぁ CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2OCH2CH2CH2SO3Naぁ CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2C(O)NHCH2SO3Na、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2NHC(O)CH2SO3Na、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2C(O)SO3Na、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2C(O)OCH2SO3Na、 CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2OC(O)CH2SO3Na, CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2SO3H, CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2SO3K, CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2SO3Li, CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2CH2SO3NH4, CH3C(O)CH2CH2CH2CH2CH2CH2CH2CH2C(CH3)2SO3Na etc.

[0318] The surfactant (d) can be produced, for example, by the production method described in WO 2020 / 022355.

[0319] Next, the surfactant (e) will be described.

[0320] In formula (e), R 1e ~R 5e represents H or a monovalent substituent, provided that R 1e and R 3e At least one of the groups has the general formula: -Y e -R 6e a group represented by R 2e and R 5e At least one of the groups has the general formula: -X e -A e or a group represented by the general formula: -Y e -R 6e R represents a group represented by 1e ~R 5e Any two of these may be bonded to each other to form a ring.

[0321] R 1eThe substituent that the alkyl group may have is preferably a halogen atom, a linear or branched alkyl group having 1 to 10 carbon atoms, a cyclic alkyl group having 3 to 10 carbon atoms, or a hydroxy group, and particularly preferably a methyl group or an ethyl group.

[0322] R 1e The alkyl group as above preferably does not contain a carbonyl group. The alkyl group may have 75% or less, 50% or less, or 25% or less of the hydrogen atoms bonded to carbon atoms substituted with halogen atoms, but is preferably a non-halogenated alkyl group that does not contain halogen atoms such as fluorine atoms or chlorine atoms. The alkyl group preferably does not have any substituents.

[0323] R 1e As the alkyl group, a linear or branched alkyl group having 1 to 10 carbon atoms which may have a substituent or a cyclic alkyl group having 3 to 10 carbon atoms which may have a substituent is preferred, a linear or branched alkyl group having 1 to 10 carbon atoms which does not contain a carbonyl group or a cyclic alkyl group having 3 to 10 carbon atoms which does not contain a carbonyl group is more preferred, a linear or branched alkyl group having 1 to 10 carbon atoms which does not contain a substituent is even more preferred, a linear or branched alkyl group having 1 to 3 carbon atoms which does not contain a substituent is even more preferred, a methyl group (-CH3) or an ethyl group (-C2H5) is particularly preferred, and a methyl group (-CH3) is most preferred.

[0324] The monovalent substituent includes a group represented by the general formula: -Y e -R 6e a group represented by the general formula: -X e -A e a group represented by the formula: -H, optionally substituted C 1-20 Alkyl groups, -NH2, -NHR 9e (R 9e represents an organic group (preferably a fluorine-free organic group), -OH, -COOR 9e (R 9eis an organic group (preferably a fluorine-free organic group) or -OR 9e (R 9e is preferably an organic group (preferably an organic group not containing fluorine). The alkyl group preferably has 1 to 10 carbon atoms.

[0325] R 9e As for C 1-10 or C 1-10 The alkylcarbonyl group of C is preferred. 1-4 or C 1-4 The alkylcarbonyl group of the formula is more preferred.

[0326] In the formula, X e represents, the same or different in each occurrence, a divalent linking group or bond. R 6e does not contain any of a carbonyl group, an ester group, an amide group, and a sulfonyl group, X e is preferably a divalent linking group containing at least one selected from the group consisting of a carbonyl group, an ester group, an amide group, and a sulfonyl group.

[0327] X e Examples include -CO-, -S(=O)2-, -O-, -COO-, -OCO-, -S(=O)2-O-, -OS(=O)2-, and -CONR 8e - and -NR 8e a divalent linking group containing at least one bond selected from the group consisting of CO—, C 1-10 An alkylene group or a bond represented by the formula R 8e represents H or an organic group (preferably an organic group not containing fluorine).

[0328] R 8e The organic group in R is preferably an alkyl group. 8e As for H or C 1-10 is preferably an organic group represented by the formula: 1-4 The organic group is more preferably H or C 1-4 More preferred is an alkyl group of the formula (I), and even more preferred is H.

[0329] In formula (e), A e may be the same or different in each occurrence, -COOM e , -SO3M e or -OSO3M e (M e is H, metal atom, NR 7e 4. An imidazolium which may have a substituent, a pyridinium which may have a substituent, or a phosphonium which may have a substituent, R 7e is H or an organic group (preferably an organic group not containing fluorine). 7e may be the same or different. In formula (e), A e Ha-COOM e This is one of the preferred embodiments.

[0330] R 7e The organic group in R is preferably an alkyl group. 7e As for H or C 1-10 is preferably an organic group represented by the formula: 1-4 The organic group is more preferably H or C 1-4 More preferred are alkyl groups of the formula: The metal atom includes alkali metals (Group 1) and alkaline earth metals (Group 2), and is preferably Na, K or Li.

[0331] M e The group may be H, a metal atom, or NR 7e 4 is preferred, H, an alkali metal (Group 1), an alkaline earth metal (Group 2) or NR 7e 4 is more preferred, H, Na, K, Li or NH4 is even more preferred, Na, K or NH4 is even more preferred, Na or NH4 is particularly preferred, and NH4 is most preferred.

[0332] In formula (e), Y e are the same or different in each occurrence, and are -S(=O)2-, -O-, -COO-, -OCO-, -CONR 8e - and -NR 8e a divalent linking group selected from the group consisting of CO—, or a bond, R 8erepresents H or an organic group (preferably an organic group not containing fluorine).

[0333] Y e Examples include bonds, -O-, -COO-, -OCO-, and -CONR. 8e - and -NR 8e A divalent linking group selected from the group consisting of -CO- is preferred, and a divalent linking group selected from the group consisting of a bond, -COO-, and -OCO- is more preferred.

[0334] R 8e The organic group in R is preferably an alkyl group. 8e As for H or C 1-10 is preferably an organic group represented by the formula: 1-4 The organic group is more preferably H or C 1-4 More preferred is an alkyl group of the formula (I), and even more preferred is H.

[0335] In formula (e), R 6e In each occurrence, R may be the same or different and represent an alkyl group having two or more carbon atoms which may contain at least one group selected from the group consisting of a carbonyl group, an ester group, an amide group and a sulfonyl group between carbon atoms. 6e The organic group (preferably an organic group containing no fluorine) preferably has 2 to 20 carbon atoms, and more preferably 2 to 10 carbon atoms.

[0336] R 6e The alkyl group of R may contain one or more groups selected from the group consisting of a carbonyl group, an ester group, an amide group, and a sulfonyl group between carbon atoms, but does not contain these groups at the terminal of the alkyl group. 6e The alkyl group may have 75% or less, 50% or less, or 25% or less of the hydrogen atoms bonded to the carbon atoms substituted with halogen atoms, but is preferably a non-halogenated alkyl group that does not contain halogen atoms such as fluorine atoms or chlorine atoms.

[0337] R 6e As for General formula:-R 10e -CO-R 11e a group represented by General formula:-R 10e -COO-R 11e a group represented by General formula:-R 11e a group represented by General formula:-R 10e -NR 8e CO-R 11e or a group represented by General formula:-R 10e -CONR 8e -R 11e a group represented by (In the formula, R 8e represents H or an organic group (preferably an organic group not containing fluorine). 10e is an alkylene group, R 11e is preferably an alkyl group which may have a substituent. R 6e As the general formula: -R 10e -CO-R 11e A group represented by the following formula is more preferred.

[0338] R 8e The organic group in R is preferably an alkyl group. 8e As for H or C 1-10 is preferably an organic group represented by the formula: 1-4 The organic group is more preferably H or C 1-4 More preferred is an alkyl group of the formula (I), and even more preferred is H.

[0339] R 10e The number of carbon atoms in the alkylene group of R is preferably 1 or more, more preferably 3 or more, and is preferably 20 or less, more preferably 12 or less, even more preferably 10 or less, and particularly preferably 8 or less. 10e The alkylene group preferably has 1 to 20 carbon atoms, more preferably 1 to 10 carbon atoms, and even more preferably 3 to 10 carbon atoms.

[0340] R 11eThe number of carbon atoms in the alkyl group may be 1 to 20, preferably 1 to 15, more preferably 1 to 12, even more preferably 1 to 10, even more preferably 1 to 8, particularly preferably 1 to 6, even more preferably 1 to 3, particularly preferably 1 or 2, and most preferably 1. 11e The alkyl group of R is preferably composed of only primary, secondary, and tertiary carbon atoms, and particularly preferably composed of only primary and secondary carbon atoms. 11e As the alkyl group, a methyl group, an ethyl group, an n-propyl group, or an isopropyl group is preferred, and a methyl group is most preferred.

[0341] In formula (e), R 2e and R 5e At least one of the groups has the general formula: -X e -A e and A is a group represented by the formula: e Ha-COOM e In one preferred embodiment,

[0342] As the surfactant (e), a compound represented by general formula (e-1), a compound represented by general formula (e-2), or a compound represented by general formula (e-3) is preferred, and a compound represented by general formula (e-1) or a compound represented by general formula (e-2) is more preferred.

[0343] General formula (e-1): [ka] (In the formula, R 3e ~R 6e , X e , A e and Y e is as above.)

[0344] General formula (e-2): [ka] (In the formula, R 4e ~R 6e , X e , A e and Ye is as above.)

[0345] General formula (e-3): [ka] (In the formula, R 2e , R 4e ~R 6e , X e , A e and Y e is as above.)

[0346] General formula:-X e -A e Examples of the group represented by the formula: -COOM e , -R 12e COOM e , -SO3M e , -OSO3M e , -R 12e SO3M e , -R 12e OSO3M e , -OCO-R 12e -COOM e , -OCO-R 12e -SO3M e , -OCO-R 12e -OSO3M e , -COO-R 12e -COOM e , -COO-R 12e -SO3M e , -COO-R 12e -OSO3M e , -CONR 8e -R 12e -COOM e , -CONR 8e -R 12e -SO3M e , -CONR 8e -R 12e -OSO3M e , -NR 8e CO-R 12e -COOM e , -NR 8e CO-R 12e -SO3M e , -NR 8e CO-R 12e -OSO3M e , -OS(=O)2-R 12e -COOM e , -OS(=O)2-R 12e -SO3M e , or -OS(=O)2-R 12e -OSO3M e (In the formula, R 8e and M e As mentioned above, R 12e is C 1-10 An alkylene group represented by the formula: is preferred. Above R 12e In the alkylene group, 75% or less of the hydrogen atoms bonded to carbon atoms may be substituted with halogen atoms, 50% or less may be substituted with halogen atoms, or 25% or less may be substituted with halogen atoms, but it is preferably a non-halogenated alkylene group that does not contain halogen atoms such as fluorine atoms or chlorine atoms.

[0347] General formula:-Y e -R 6e Examples of the group represented by the formula: General formula:-R 10e -CO-R 11e a group represented by General formula:-OCO-R 10e -CO-R 11e a group represented by General formula:-COO-R 10e -CO-R 11e a group represented by General formula:-OCO-R 10e-COO-R 11e a group represented by General formula:-COO-R 11e a group represented by General formula:-NR 8e CO-R 10e -CO-R 11e or a group represented by General formula:-CONR 8e -R 10e -NR 8e CO-R 11e A group represented by (In the formula, R 8e , R 10e and R 11e is as described above.) is preferred.

[0348] In the formula, R 4e and R 5e are independently H or C 1-4 The alkyl groups are preferably: Above R 4e and R 5e The alkyl group may have 75% or less, 50% or less, or 25% or less of the hydrogen atoms bonded to the carbon atoms substituted with halogen atoms, but is preferably a non-halogenated alkyl group that does not contain halogen atoms such as fluorine atoms or chlorine atoms.

[0349] R in general formula (e-1) 3e is H or optionally substituted C 1-20 The alkyl group is preferably H or unsubstituted C 1-20 An alkyl group represented by the formula (I) is more preferred, and H is even more preferred. Above R 3e The alkyl group may have 75% or less, 50% or less, or 25% or less of the hydrogen atoms bonded to the carbon atoms substituted with halogen atoms, but is preferably a non-halogenated alkyl group that does not contain halogen atoms such as fluorine atoms or chlorine atoms.

[0350] R in general formula (e-3) 2e is H, OH or optionally substituted C 1-20 The alkyl group having no H, OH or substituent is preferably C 1-20 An alkyl group such as the above is more preferred, and H or OH is even more preferred. Above R 2e The alkyl group may have 75% or less, 50% or less, or 25% or less of the hydrogen atoms bonded to the carbon atoms substituted with halogen atoms, but is preferably a non-halogenated alkyl group that does not contain halogen atoms such as fluorine atoms or chlorine atoms.

[0351] The surfactant (e) can be produced by a known production method.

[0352] The specific hydrocarbon surfactant is preferably a carboxylic acid type hydrocarbon surfactant. The carboxylic acid type hydrocarbon surfactant is not limited as long as it has a carboxyl group (-COOH) or a group in which the hydrogen atom of the carboxyl group is substituted with an inorganic cation (for example, a metal atom, ammonium, etc.), and for example, from among the specific hydrocarbon surfactants described above, a hydrocarbon surfactant having a carboxyl group or a group in which the hydrogen atom of the carboxyl group is substituted with an inorganic cation can be used. In the above-mentioned carboxylic acid type hydrocarbon surfactant, the ratio of hydrogen atoms bonded to carbon atoms substituted with fluorine atoms is preferably 50% or less, more preferably 25% or less, even more preferably 10% or less, and most preferably 0% (no substitution with fluorine atoms at all).

[0353] The carboxylic acid type hydrocarbon surfactant is preferably at least one selected from the group consisting of surfactants (c) represented by the above formula (c) and surfactants (d) represented by the above formula (d), which have a carboxyl group (-COOH) or a group in which the hydrogen atom of the carboxyl group is substituted with an inorganic cation (e.g., a metal atom, ammonium, etc.).

[0354] It is also preferable that the specific hydrocarbon surfactant is a sulfonic acid hydrocarbon surfactant. The sulfonic acid hydrocarbon surfactant is not limited as long as it has a -SO3H group, a -OSO3H group, or a group in which the hydrogen atom of these groups is substituted with an inorganic cation (for example, a metal atom, ammonium, etc.). For example, from the specific hydrocarbon surfactants described above, a hydrocarbon surfactant having a -SO3H group, a -OSO3H group, or a group in which the hydrogen atom of these groups is substituted with an inorganic cation can be used. In the sulfonic acid type hydrocarbon surfactant, the ratio of hydrogen atoms bonded to carbon atoms substituted with fluorine atoms is preferably 50% or less, more preferably 25% or less, even more preferably 10% or less, and most preferably 0% (no substitution with fluorine atoms at all).

[0355] The TFE polymer composition of the present disclosure can be efficiently produced by using at least one of the specific hydrocarbon surfactants. The TFE polymer composition of the present disclosure may be produced by simultaneously using two or more of the specific hydrocarbon surfactants, or may be produced by simultaneously using other surfactant compounds other than the specific hydrocarbon surfactants, as long as they are volatile or may remain in a molded product or the like made of a TFE polymer.

[0356] As the other compounds having surface activity, for example, those described in JP-A Nos. 2013-542308, 2013-542309, and 2013-542310 can be used.

[0357] Other surface-active compounds may be surfactants having a hydrophilic portion and a hydrophobic portion on the same molecule, such as hydrocarbon surfactants, which may be cationic, nonionic, or anionic. In the above compound, the ratio of hydrogen atoms bonded to carbon atoms substituted with fluorine atoms is preferably 50% or less, more preferably 25% or less, even more preferably 10% or less, and most preferably 0% (no substitution with fluorine atoms).

[0358] Cationic surfactants typically have a positively charged hydrophilic portion, such as an alkylated ammonium halide, such as an alkylated ammonium bromide, and a hydrophobic portion, such as a long-chain fatty acid. In the cationic surfactant, the proportion of hydrogen atoms bonded to carbon atoms that are substituted with fluorine atoms is preferably 50% or less, more preferably 25% or less, even more preferably 10% or less, and most preferably 0% (no substitution with fluorine atoms at all).

[0359] Anionic surfactants typically have a hydrophilic portion, such as a carboxylate, sulfonate, or sulfate, and a hydrophobic portion, which is a long chain hydrocarbon moiety, such as an alkyl. In the anionic surfactant, the proportion of hydrogen atoms bonded to carbon atoms that are substituted with fluorine atoms is preferably 50% or less, more preferably 25% or less, even more preferably 10% or less, and most preferably 0% (no substitution with fluorine atoms).

[0360] Nonionic surfactants typically contain no charged groups and have a hydrophobic portion that is a long hydrocarbon chain. The hydrophilic portion of the nonionic surfactant contains water-soluble functional groups, such as ethylene ether chains derived from polymerization with ethylene oxide. In the nonionic surfactant, the ratio of hydrogen atoms bonded to carbon atoms substituted with fluorine atoms is preferably 50% or less, more preferably 25% or less, even more preferably 10% or less, and most preferably 0% (no substitution with fluorine atoms at all).

[0361] Examples of nonionic surfactants Polyoxyethylene alkyl ethers, polyoxyethylene alkylphenyl ethers, polyoxyethylene alkyl esters, sorbitan alkyl esters, polyoxyethylene sorbitan alkyl esters, glycerol esters, and derivatives thereof.

[0362] Specific examples of polyoxyethylene alkyl ethers include polyoxyethylene lauryl ether, polyoxyethylene cetyl ether, polyoxyethylene stearyl ether, polyoxyethylene oleyl ether, and polyoxyethylene behenyl ether.

[0363] Specific examples of polyoxyethylene alkylphenyl ethers include polyoxyethylene nonylphenyl ether and polyoxyethylene octylphenyl ether.

[0364] Specific examples of polyoxyethylene alkyl esters include polyethylene glycol monolaurate, polyethylene glycol monooleate, and polyethylene glycol monostearate.

[0365] Specific examples of sorbitan alkyl esters include polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, polyoxyethylene sorbitan monostearate, and polyoxyethylene sorbitan monooleate.

[0366] Specific examples of polyoxyethylene sorbitan alkyl esters include polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan monopalmitate, and polyoxyethylene sorbitan monostearate.

[0367] Specific examples of glycerol esters include glycerol monomyristate, glycerol monostearate, and glycerol monooleate.

[0368] Specific examples of the above derivatives include polyoxyethylene alkylamines, polyoxyethylene alkylphenyl-formaldehyde condensates, polyoxyethylene alkyl ether phosphates, and the like.

[0369] The ethers and esters may have an HLB value of 10-18.

[0370] Examples of nonionic surfactants include the Triton (registered trademark) X series (X15, X45, X100, etc.), Tergitol (registered trademark) 15-S series, Tergitol (registered trademark) TMN series (TMN-6, TMN-10, TMN-100, etc.), and Tergitol (registered trademark) L series, all manufactured by Dow Chemical Company; the Pluronic (registered trademark) R series (31R1, 17R2, 10R5, 25R4 (m to 22, n to 23)), and the Iconol (registered trademark) TDA series (TDA-6, TDA-9, TDA-10).

[0371] Examples of anionic hydrocarbon surfactants include Versatic (registered trademark) 10 manufactured by Resolution Performance Products, and Avanel S series (S-70, S-74, etc.) manufactured by BASF.

[0372] Other compounds having surface activity include RLM (wherein R is a linear or branched alkyl group having one or more carbon atoms which may have a substituent, or a cyclic alkyl group having three or more carbon atoms which may have a substituent, and when the number of carbon atoms is three or more, it may contain a monovalent or divalent heterocycle or may form a ring). L is -ArSO3 - , -SO3 - , -SO4-, -PO3 - or -COO - and M is H, a metal atom, or NR 5 4(R 5 may be the same or different and are H or an organic group (preferably an organic group not containing fluorine), an imidazolium group which may have a substituent, a pyridinium group which may have a substituent, or a phosphonium group which may have a substituent. - is an aryl sulfonate. )5 is preferably H or an organic group having 1 to 10 carbon atoms, more preferably H or an organic group having 1 to 4 carbon atoms. Specifically, CH3-(CH2) such as lauric acid n -LM (wherein n is an integer of 6 to 17, and L and M are the same as above). Mixtures in which R is an alkyl group having 12 to 16 carbon atoms and LM is sulfate or sodium dodecyl sulfate (SDS) can also be used. Other surfactant compounds include R 6 (-LM)2(wherein, R 6 is a linear or branched alkylene group having one or more carbon atoms which may have a substituent, or a cyclic alkylene group having three or more carbon atoms which may have a substituent, and when the number of carbon atoms is three or more, it may contain a monovalent or divalent heterocycle or may form a ring. - , -SO3 - , -SO4-, -PO3 - or -COO - and M is H, a metal atom, or NR 5 4. An imidazolium which may have a substituent, a pyridinium which may have a substituent, or a phosphonium which may have a substituent, R 5 is H or an organic group (preferably an organic group not containing fluorine), -ArSO3 - is an aryl sulfonate. ) Other surfactant compounds include R 7 (-LM)3(wherein, R 7 is a linear or branched alkylidyne group having one or more carbon atoms which may have a substituent, or a cyclic alkylidyne group having three or more carbon atoms which may have a substituent, and when the number of carbon atoms is three or more, it may contain a monovalent or divalent heterocycle or may form a ring. - , -SO3 - , -SO4-, -PO3 - or -COO - and M is H, a metal atom, or NR5 4. An imidazolium which may have a substituent, a pyridinium which may have a substituent, or a phosphonium which may have a substituent, R 5 is H or an organic group (preferably an organic group that does not contain fluorine). - is an aryl sulfonate. )

[0373] Siloxane hydrocarbon surfactants include those described in Silicone Surfactants, R.M. Hill, Marcel Dekker, Inc., ISBN: 0-8247-00104. The structure of the siloxane surfactant comprises a distinct hydrophobic portion and a hydrophilic portion. The hydrophobic portion comprises one or more dihydrocarbylsiloxane units, where the substituents on the silicone atom are entirely hydrocarbon. These siloxane surfactants can also be considered hydrocarbon surfactants in the sense that the carbon atoms of the hydrocarbyl groups are fully substituted by hydrogen atoms, which may be substituted by halogens such as fluorine, i.e., the monovalent substituents on the carbon atoms of the hydrocarbyl groups are hydrogen. In the above siloxane surfactant, the proportion of hydrogen atoms bonded to carbon atoms that are substituted with fluorine atoms is preferably 50% or less, more preferably 25% or less, even more preferably 10% or less, and most preferably 0% (no substitution with fluorine atoms at all).

[0374] Siloxane hydrocarbon surfactants are also disclosed in US Pat. No. 6,841,616.

[0375] Siloxane-based anionic hydrocarbon surfactants include SilSense available from Noveon® Consumer Specialties, manufactured by Lubrizol Advanced Materials, Inc. TM PE-100 Silicone, SilSense TM CA-1 silicone and the like.

[0376] Examples of anionic hydrocarbon surfactants include the sulfosuccinate surfactant Lankropol (registered trademark) K8300 manufactured by Akzo Nobel Surface Chemistry LLC. Examples of sulfosuccinate surfactants include sodium diisodecyl sulfosuccinate (Emulsogen (registered trademark) SB10 manufactured by Clariant) and sodium diisotridecyl sulfosuccinate (Polirol (registered trademark) TR / LNA manufactured by Cesapinia Chemicals).

[0377] Other surfactant compounds include PolyFox (registered trademark) surfactants manufactured by Omnova Solutions, Inc. TM PF-156A, PolyFox TM PF-136A, etc.)

[0378] The other surfactant compound is preferably an anionic hydrocarbon surfactant. As the anionic hydrocarbon surfactant, those described above can be used, but for example, the following hydrocarbon surfactants can be suitably used.

[0379] Examples of the anionic hydrocarbon surfactant include those represented by the following formula (α): R 100 -COOM (α) (In the formula, R 100 is a monovalent organic group containing one or more carbon atoms (preferably an organic group not containing fluorine); M is H, a metal atom, NR 101 4. An optionally substituted imidazolium, an optionally substituted pyridinium, or an optionally substituted phosphonium, wherein R 101 R is H or an organic group (preferably an organic group not containing fluorine), and may be the same or different. 101 The organic group in R is preferably an alkyl group. 101is preferably H or an organic group having 1 to 10 carbon atoms, more preferably H or an organic group having 1 to 4 carbon atoms, and even more preferably H or an alkyl group having 1 to 4 carbon atoms. From the viewpoint of surfactant activity, R 100 The number of carbon atoms in R is preferably 2 or more, and more preferably 3 or more. 100 The number of carbon atoms is preferably 29 or less, and more preferably 23 or less. The metal atom of M includes alkali metals (Group 1) and alkaline earth metals (Group 2), and is preferably Na, K, or Li. M may be H, a metal atom, or NR 101 4 is preferred, H, an alkali metal (Group 1), an alkaline earth metal (Group 2) or NR 101 4 is more preferred, H, Na, K, Li or NH4 is even more preferred, Na, K or NH4 is even more preferred, Na or NH4 is particularly preferred, and NH4 is most preferred.

[0380] The compound (α) includes R 102 -COOM(in the formula, R 102 is a linear or branched alkyl group, alkenyl group, alkylene group or alkenylene group having 1 or more carbon atoms which may have a substituent, or a cyclic alkyl group, alkenyl group, alkylene group or alkenylene group having 3 or more carbon atoms which may have a substituent, and these may contain an ether bond. When the number of carbon atoms is 3 or more, it may contain a monovalent or divalent heterocycle or may form a ring. M is the same as above.) Specifically, CH3-(CH2) n -COOM (wherein n is an integer of 2 to 28, and M is the same as above).

[0381] From the viewpoint of emulsion stability, the compound (α) may not contain a carbonyl group (excluding a carbonyl group in a carboxyl group). Examples of the hydrocarbon-containing surfactant that does not contain a carbonyl group include surfactants represented by the following formula (A1): R 103-COO-M (A1) (In the formula, R 103 is an alkyl group, an alkenyl group, an alkylene group, or an alkenylene group containing 6 to 17 carbon atoms, which may contain an ether bond; M is H, a metal atom, NR 101 4. An imidazolium which may have a substituent, a pyridinium which may have a substituent, or a phosphonium which may have a substituent. 101 are the same or different and each represents H or an organic group (preferably an organic group not containing fluorine). In the above formula (A1), R 103 is preferably an alkyl group or an alkenyl group (which may contain an ether group). 103 The alkyl group or alkenyl group in the above R may be linear or branched. 103 The number of carbon atoms is not limited, but is, for example, 2 to 29.

[0382] When the alkyl group is linear, R 103 The number of carbon atoms in R is preferably 3 to 29, and more preferably 5 to 23. When the alkyl group is branched, R 103 The number of carbon atoms is preferably 5 to 35, and more preferably 11 to 23. When the alkenyl group is linear, R 103 The number of carbon atoms in R is preferably 2 to 29, and more preferably 9 to 23. When the alkenyl group is branched, R 103 The number of carbon atoms is preferably 2 to 29, and more preferably 9 to 23.

[0383] Examples of the alkyl group and alkenyl group include a methyl group, an ethyl group, an isobutyl group, a t-butyl group, and a vinyl group.

[0384] Examples of the compound (α) include butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, lauric acid, myristic acid, pentadecylic acid, palmitic acid, palmitoleic acid, margaric acid, stearic acid, oleic acid, vaccenic acid, linoleic acid, (9,12,15)-linolenic acid, (6,9,12)linolenic acid, eleostearic acid, arachidic acid, 8,11-eicosadienoic acid, mead acid, arachidonic acid, behenic acid, lignoceric acid, nervonic acid, cerotic acid, montanic acid, melissic acid, croscarmellose ... Examples of suitable oleic acids include oleic acid, myristoleic acid, palmitoleic acid, sapienic acid, elaidic acid, gadoleic acid, eicosenoic acid, erucic acid, nervonic acid, eicosadienoic acid, docosadienoic acid, linolenic acid, pinolenic acid, α-eleostearic acid, β-eleostearic acid, dihomo-γ-linolenic acid, eicosatrienoic acid, stearidonic acid, arachidonic acid, eicosatetraenoic acid, adrenic acid, bosseopentaenoic acid, eicosapentaenoic acid, osbondo acid, sardine acid, tetracosapentaenoic acid, docosahexaenoic acid, herring acid, and salts thereof. Particularly, at least one selected from the group consisting of lauric acid, capric acid, myristic acid, pentadecylic acid, palmitic acid, and salts thereof is preferred. The salts include those in which the hydrogen of the carboxyl group is replaced by a metal atom of the formula M, NR 11 4. Examples include, but are not limited to, imidazolium which may have a substituent, pyridinium which may have a substituent, or phosphonium which may have a substituent.

[0385] The anionic hydrocarbon surfactant also includes, for example, a surfactant represented by the following formula (β): R 100 -SO3M (β) (In the formula, R 100 is a monovalent organic group containing one or more carbon atoms (preferably an organic group not containing fluorine); M is H, a metal atom, NR 101 4. An optionally substituted imidazolium, an optionally substituted pyridinium, or an optionally substituted phosphonium, wherein R 101R is H or an organic group (preferably an organic group not containing fluorine), and may be the same or different. 101 The organic group in R is preferably an alkyl group. 101 is preferably H or an organic group having 1 to 10 carbon atoms, more preferably H or an organic group having 1 to 4 carbon atoms, and even more preferably H or an alkyl group having 1 to 4 carbon atoms. From the viewpoint of surfactant activity, R 100 The number of carbon atoms in R is preferably 2 or more, and more preferably 3 or more. 100 The number of carbon atoms is preferably 29 or less, and more preferably 23 or less. The metal atom of M includes alkali metals (Group 1) and alkaline earth metals (Group 2), and is preferably Na, K, or Li. M may be H, a metal atom, or NR 101 4 is preferred, H, an alkali metal (Group 1), an alkaline earth metal (Group 2) or NR 101 4 is more preferred, H, Na, K, Li or NH4 is even more preferred, Na, K or NH4 is even more preferred, Na or NH4 is particularly preferred, and NH4 is most preferred.

[0386] The compound (β) includes R 102 -SO3M (in the formula, R 102 is a linear or branched alkyl group, alkenyl group, alkylene group or alkenylene group having 1 or more carbon atoms which may have a substituent, or a cyclic alkyl group, alkenyl group, alkylene group or alkenylene group having 3 or more carbon atoms which may have a substituent, and these may contain an ether bond. When the number of carbon atoms is 3 or more, it may contain a monovalent or divalent heterocycle or may form a ring. M is the same as above.) Specifically, CH3-(CH2) n -SO3M (wherein n is an integer of 2 to 28, and M is the same as above) are exemplified.

[0387] From the viewpoint of emulsion stability, the compound (β) may not contain a carbonyl group (excluding a carbonyl group in a carboxyl group). Examples of the hydrocarbon-containing surfactant that does not contain a carbonyl group include surfactants represented by the following formula (B1): R 103 -SO3-M (B1) (In the formula, R 103 is an alkyl group, an alkenyl group, an alkylene group, or an alkenylene group containing 6 to 17 carbon atoms, which may contain an ether bond; M is H, a metal atom, NR 101 4. An imidazolium which may have a substituent, a pyridinium which may have a substituent, or a phosphonium which may have a substituent. 101 are the same or different and each represents H or an organic group (preferably an organic group not containing fluorine). In the above formula (B), R 103 is preferably an alkyl group or an alkenyl group (which may contain an ether group). 103 The alkyl group or alkenyl group in the above R may be linear or branched. 103 The number of carbon atoms is not limited, but is, for example, 2 to 29.

[0388] When the alkyl group is linear, R 103 The number of carbon atoms in R is preferably 3 to 29, and more preferably 5 to 23. When the alkyl group is branched, R 103 The number of carbon atoms is preferably 5 to 35, and more preferably 11 to 23. When the alkenyl group is linear, R 103 The number of carbon atoms in R is preferably 2 to 29, and more preferably 9 to 23. When the alkenyl group is branched, R 103 The number of carbon atoms is preferably 2 to 29, and more preferably 9 to 23.

[0389] Examples of the alkyl group and alkenyl group include a methyl group, an ethyl group, an isobutyl group, a t-butyl group, and a vinyl group.

[0390] Examples of the compound (β) include aliphatic, unsaturated aliphatic, and aromatic sulfonic acids, aliphatic, unsaturated aliphatic, and aromatic sulfates, and salts thereof. Examples of the sulfonic acids include 1-hexanesulfonic acid, 1-octane sulfonic acid, 1-decanesulfonic acid, 1-dodecanesulfonic acid, perfluorobutanesulfonic acid, linear alkylbenzenesulfonic acid, toluenesulfonic acid, cumenesulfonic acid, octylbenzenesulfonic acid, DBS, naphthalenesulfonic acid, naphthalenedisulfonic acid, naphthalenetrisulfonic acid, and butylnaphthalenesulfonic acid. Examples of the sulfates include sodium alkyl sulfates, alpha-sulfofatty acid ester salts, alkyl sulfate ester salts, polyoxyethylene alkyl ether sulfate ester salts, alpha-olefin sulfonates, lauryl sulfate, myristyl sulfate, laureth sulfate, and polyoxyethylene alkylphenol sulfonic acid. As the compound (β), at least one selected from the group consisting of saturated aliphatic and aromatic sulfate esters and their salts is particularly preferred, and at least one selected from the group consisting of sodium alkyl sulfate esters, alpha-sulfofatty acid ester salts, alkyl sulfate ester salts, polyoxyethylene alkyl ether sulfate ester salts, alpha-olefin sulfonates, lauryl sulfate, myristyl sulfate, laureth sulfate, polyoxyethylene alkylphenol sulfonic acid, and their salts is more preferred. The salts include those in which the hydrogen of the sulfonic acid group is replaced by a metal atom of the above formula M, NR 11 4. Examples include, but are not limited to, imidazolium which may have a substituent, pyridinium which may have a substituent, or phosphonium which may have a substituent.

[0391] The anionic hydrocarbon surfactant may be a surfactant represented by the following formula (1-0A): [ka] (In the formula, R 1A ~R 5A represents H, a monovalent hydrocarbon group which may contain an ester group between carbon atoms, or a group represented by the general formula: -X A -A, where R 2A and R 5A At least one of the groups has the general formula: -X A - represents a group represented by A. X A is, in each occurrence, the same or different, a divalent hydrocarbon radical or a bond; A is the same or different in each occurrence and is -COOM (M is H, a metal atom, NR 7 4. An imidazolium which may have a substituent, a pyridinium which may have a substituent, or a phosphonium which may have a substituent, R 7 is H or an organic group (preferably a fluorine-free organic group); R 1A ~R 5A Any two of these may be bonded to each other to form a ring.

[0392] In general formula (1-0A), R 1A ~R 5A In R, the monovalent hydrocarbon group which may contain an ester group between carbon atoms preferably has 1 to 50 carbon atoms, and more preferably has 5 to 20 carbon atoms. 1A ~R 5A Any two of these may be bonded to each other to form a ring. The monovalent hydrocarbon group which may contain an ester group between carbon atoms is preferably an alkyl group. In the formula, X A In the formula, the number of carbon atoms in the divalent hydrocarbon group is preferably 1 to 50, and more preferably 5 to 20. Examples of the divalent hydrocarbon group include an alkylene group and an alkanediyl group, with an alkylene group being preferred.

[0393] In general formula (1-0A), R2A and R 5A any one of the above general formula: -X A -A is preferred, and R 2A is represented by the above general formula: -X A A group represented by -A is more preferred.

[0394] In the general formula (1-0A), a preferred embodiment is R 2A is represented by the general formula: -X A -A, and R 1A , R 3A , R 4A and R 5A is H. In this case, X A is preferably a bond or an alkylene group having 1 to 5 carbon atoms.

[0395] In the general formula (1-0A), a preferred embodiment is also R 2A is represented by the general formula: -X A -A, and R 1A and R 3A Ga-Y A -R 6 and Y A is the same or different in each occurrence and is -COO-, -OCO-, or a bond; R 6 are the same or different in each occurrence and are alkyl groups having 2 or more carbon atoms. In this case, R 4A and R 5A is preferably H.

[0396] Examples of hydrocarbon surfactants represented by general formula (1-0A) include glutaric acid or a salt thereof, adipic acid or a salt thereof, pimelic acid or a salt thereof, suberic acid or a salt thereof, azelaic acid or a salt thereof, and sebacic acid or a salt thereof. Furthermore, the aliphatic carboxylic acid hydrocarbon surfactant represented by general formula (1-0A) may be a two-chain two-hydrophilic group synthetic surfactant, and examples of such Gemini surfactants include Geminisurf (Chukyo Yushi Co., Ltd.), Gemsurf α142 (12 carbon atoms, lauryl group), Gemsurf α102 (10 carbon atoms), and Gemsurf α182 (14 carbon atoms).

[0397] The anionic hydrocarbon surfactant may be a surfactant represented by the following formula I: R-(XZ) n (I) (wherein R is a hydrophobic hydrocarbon moiety containing one or more saturated or unsaturated, acyclic or cyclic aliphatic groups; the percentage of the total of CH groups relative to the total of CH, CH, and CH groups in the one or more aliphatic groups is at least about 70%, and the hydrophobic moiety does not contain a siloxane unit; each X, which may be the same or different, represents an ionic hydrophilic moiety; each Z, which may be the same or different, represents one or more counter ions of the ionic hydrophilic moiety; and n is 1 to 3.)

[0398] Compound I exhibits low reactivity with the polymerization initiator and / or propagating fluoropolymer radical in the emulsion polymerization of fluoromonomers.

[0399] Compound I has the formula: [ka] (In the formula, Y + is hydrogen, ammonium, quaternary ammonium, a nitrogen heterocycle, an alkali metal, or an alkaline earth metal.

[0400] Compound I has the following formula II: [ka] (In the formula, R 2’ and R 2’’’are the same or different and are saturated or unsaturated, acyclic or cyclic aliphatic groups having 4 to 16 carbon atoms; R 2’ and R 2’’’ the percentage of the total of CH3 groups to the total of CH3, CH2 and CH groups in the group is at least about 70%, or 2’ and R 2’’’ may be linked together to form a saturated or unsaturated aliphatic ring which may contain ether or ester linkages, provided that the percentage of the total of CH3 groups relative to the total of CH3, CH2, and CH groups in the ring is at least about 70%. 1 is hydrogen, methoxy, ethoxy or phenoxy. + is hydrogen, ammonium, quaternary ammonium, a nitrogen heterocycle, an alkali metal, or an alkaline earth metal.

[0401] As compound II, for example, the following compounds are preferred. [ka] Y in the above formula + may be hydrogen, ammonium, or an alkali metal.

[0402] Compound I has the following formula III: [ka] (In the formula, R 3 , R 4’ , and R 4’’ are the same or different and are hydrogen or a saturated or unsaturated, acyclic or cyclic aliphatic group having 4 to 16 carbon atoms; R 3 , R 4’ , and R 4’’ The percentage of total CH3 with respect to the total of CH3, CH2 and CH groups in the group is at least about 70%, provided that R 3 , R 4’ , and R 4’’ At least one of the groups is not hydrogen, and R 4’ and R 4’’ is hydrogen, R3 is not hydrogen, but R 3 is hydrogen, R 4’ and R 4’’ is not hydrogen. Y + is hydrogen, ammonium, quaternary ammonium, a nitrogen heterocycle, an alkali metal, or an alkaline earth metal.

[0403] As the compound III, for example, the following compounds are preferred. [ka] Y in the above formula + may be hydrogen, ammonium, or an alkali metal.

[0404] The TFE polymer composition of the present disclosure can be obtained, even in the case where the above-mentioned specific hydrocarbon surfactant is not used, by a production method including a polymerization step of polymerizing tetrafluoroethylene alone or tetrafluoroethylene and the above-mentioned modified monomer copolymerizable with tetrafluoroethylene in an aqueous medium having a pH of 4.0 or higher in the presence of a hydrocarbon surfactant and a polymerization initiator to obtain a TFE polymer. Conventionally, an acidic polymerization initiator has been used in the polymerization process for producing a TFE-based polymer, and therefore the pH of the aqueous medium used in the polymerization has been less than 4.0. As a result of intensive studies by the present inventors, it has been unexpectedly found that the stability of the polymerization can be improved by adjusting the pH of the aqueous medium used in the polymerization to 4.0 or more, and a TFE-based polymer with a high molecular weight can be produced. In the above production method, tetrafluoroethylene alone, or tetrafluoroethylene and a modified monomer copolymerizable with the tetrafluoroethylene, are polymerized in an aqueous medium having a pH of 4.0 or higher. The pH may be 4.0 or higher, preferably greater than 4.0, more preferably 4.5 or higher, even more preferably 5.0 or higher, even more preferably 5.5 or higher, especially preferably 6.0 or higher, particularly preferably 6.5 or higher, particularly preferably 7.0 or higher, particularly preferably 7.5 or higher, and particularly preferably 8.0 or higher. The upper limit of the pH is not particularly limited, but may be, for example, 13.0 or lower. From the viewpoint of corrosion of the polymerization vessel, it is preferably 12.0 or lower, more preferably 11.5 or lower, and even more preferably 11.0 or lower. The pH can be measured using a pH meter.

[0405] In the above-mentioned production method, the method for adjusting the pH of the aqueous medium to 4.0 or higher is not particularly limited. For example, the pH can be adjusted to 4.0 or higher by using an alkaline aqueous solution, an alkaline aqueous dispersion, or a pH adjuster, but is not particularly limited thereto. Even when a polymerization initiator that is acidic when dissolved in an aqueous medium is used, the pH can be adjusted to 4.0 or higher by further adding an alkaline compound such as sodium hydroxide. - Any compound capable of generating the above-mentioned polymerization reaction may be used, and examples thereof include, but are not limited to, hydroxides of alkali metals such as sodium hydroxide and potassium hydroxide; hydroxides of alkaline earth metals; ammonia; amines, etc. The polymerization step may include a step of adding an alkali compound to the aqueous medium.

[0406] In the above production method, the pH of the aqueous medium may be 4.0 or higher throughout the entire polymerization step. Alternatively, the pH may be 4.0 or higher in the middle of the polymerization step, or in the latter half of the polymerization step. Alternatively, the pH may be 4.0 or higher in both the middle and latter half of the polymerization step.

[0407] In the above-mentioned production method, the hydrocarbon surfactant is a fluorine-free hydrocarbon surfactant, preferably an anionic hydrocarbon surfactant, more preferably a carboxylic acid hydrocarbon surfactant. The anionic hydrocarbon surfactant and the carboxylic acid hydrocarbon surfactant are not particularly limited, but for example, the compound (α) exemplified among the above-mentioned other compounds having surface activity can be suitably used.

[0408] In the above-mentioned production method, the hydrocarbon surfactant is a fluorine-free hydrocarbon surfactant, preferably an anionic hydrocarbon surfactant, and also preferably a sulfonic acid hydrocarbon surfactant. The anionic hydrocarbon surfactant and the sulfonic acid hydrocarbon surfactant are not particularly limited. For example, the compound (β) exemplified among the above-mentioned other compounds having surface activity can be suitably used.

[0409] Even if the TFE polymer composition of the present disclosure does not use the above-mentioned specific hydrocarbon surfactant, it comprises the polymerization step of obtaining a TFE polymer by polymerizing tetrafluoroethylene alone or tetrafluoroethylene and the modified monomer copolymerizable with the above-mentioned tetrafluoroethylene in an aqueous medium in the presence of anionic hydrocarbon surfactant and a polymerization initiator, and the above-mentioned hydrocarbon surfactant comprises the salt of the hydrocarbon surfactant.In other words, at least a part of the anionic hydrocarbon surfactant in the above-mentioned polymerization step is in the form of a salt. As a result of intensive studies, the present inventors have unexpectedly found that when an anionic hydrocarbon surfactant contains a salt of the anionic hydrocarbon surfactant, the stability of polymerization is improved and a TFE polymer having a large molecular weight can be produced. The anionic hydrocarbon surfactants will be described later. Whether the anionic hydrocarbon surfactant contains a salt of the hydrocarbon surfactant can be confirmed by measuring the electrical conductivity. In the above-mentioned production method, the concentration of the salt of the anionic hydrocarbon surfactant is preferably 50% by mass or more, more preferably 60% by mass or more, even more preferably 70% by mass or more, even more preferably 80% by mass or more, particularly preferably 90% by mass or more, and particularly preferably 95% by mass or more, relative to the total mass of the anionic hydrocarbon surfactant. The proportion of the salt can be measured by the solution concentration and conductivity. In the above-mentioned production method, the hydrocarbon surfactant is preferably a carboxylic acid-type hydrocarbon surfactant, and the hydrocarbon surfactant does not contain fluorine. In the salts of anionic hydrocarbon surfactants, the cations (excluding hydrogen atoms) that replace the hydrogen atoms of the acid are, for example, metal atoms, NR y 4(R y may be the same or different and each represents H or an organic group (preferably an organic group not containing fluorine), an imidazolium group which may have a substituent, a pyridinium group which may have a substituent, or a phosphonium group which may have a substituent. y is preferably H or an alkyl group, more preferably H or an alkyl group having 1 to 10 carbon atoms, and even more preferably H or an alkyl group having 1 to 4 carbon atoms. The cation in the salt of the anionic hydrocarbon surfactant may be a metal atom or NR y 4 is preferred, NR y 4 is more preferred, and NH4 is even more preferred. Since conductivity is greatly affected by temperature, a thermostatic bath is used to keep the sample liquid temperature at 25°C, and the pH meter cell temperature is also kept at the same level before measuring the conductivity.

[0410] In the above-mentioned production method, the polymerization step is preferably carried out substantially in the absence of the hydrocarbon surfactant in the form of an organic acid. By carrying out the polymerization substantially in the absence of the hydrocarbon surfactant in the form of an organic acid, the stability of the polymerization is further improved, and a high molecular weight TFE polymer can be obtained. Substantially in the absence of the hydrocarbon surfactant in the form of an organic acid means that the concentration of the organic acid is preferably 1.0 mass% or less, more preferably 0.5 mass% or less, even more preferably 0.1 mass% or less, particularly preferably 0.05 mass% or less, and particularly preferably 0.01 mass% or less, relative to the mass of the obtained aqueous dispersion. In this specification, the term "organic acid" refers to an organic compound that exhibits acidity. Examples of organic acids include carboxylic acids having a -COOH group and sulfonic acids having a -SOH group. Carboxylic acids are preferred because they allow for easy adjustment of the pH of an aqueous solution containing the organic acid. Furthermore, the "form of organic acid" refers to a form in which the H of the acidic group (for example, -COOH group, -SO3H group, etc.) contained in the organic acid is not free. In the above production method, the hydrocarbon surfactant is an anionic hydrocarbon surfactant.

[0411] In the polymerization step, the amount of hydrocarbon surfactant at the start of polymerization is preferably more than 50 ppm relative to the aqueous medium. The amount of hydrocarbon surfactant at the start of polymerization is preferably 60 ppm or more, more preferably 70 ppm or more, even more preferably 80 ppm or more, and even more preferably 100 ppm or more. There is no particular upper limit, but for example, it is preferably 10,000 ppm, and more preferably 5,000 ppm. By keeping the amount of hydrocarbon surfactant at the start of polymerization within the above range, an aqueous dispersion having a smaller average primary particle size and better stability can be obtained. Polymerization can be said to have begun when the gaseous TFE in the reactor becomes a TFE-based polymer and a pressure drop occurs in the reactor. U.S. Pat. No. 3,391,099 (Punderson) discloses dispersion polymerization of tetrafluoroethylene in an aqueous medium, which consists of two distinct stages in the polymerization process: first, the formation of polymer nuclei as nucleation sites, and then, a growth stage involving the polymerization of the established particles. Polymerization usually begins when both the monomer to be polymerized and the polymerization initiator are charged into the reactor. In this disclosure, the additive involved in the formation of nucleation sites is referred to as a nucleating agent.

[0412] The polymerization step preferably includes an addition step of adding a composition containing a hydrocarbon surfactant after the initiation of polymerization, which further improves the stability of the polymerization and allows a TFE polymer with a higher molecular weight to be obtained. The hydrocarbon surfactant may be in the form of, for example, a solid (for example, a powder of a hydrocarbon surfactant) or a liquid. The composition may be any composition containing a hydrocarbon surfactant, and may consist of only a hydrocarbon surfactant, or may be a solution or dispersion of a hydrocarbon surfactant containing a hydrocarbon surfactant and a liquid medium. Therefore, the addition step can also be said to be a step of adding a hydrocarbon surfactant alone or a composition containing a hydrocarbon surfactant after the initiation of polymerization. The hydrocarbon surfactant is not limited to one type, and may be a mixture of two or more types. The liquid medium may be either an aqueous medium or an organic solvent, or a combination of an aqueous medium and an organic solvent may be used. Specific examples of the composition include an aqueous solution in which a hydrocarbon surfactant is dissolved in an aqueous medium, and an aqueous dispersion in which a hydrocarbon surfactant is dispersed in an aqueous medium.

[0413] The amount of the hydrocarbon surfactant added in the addition step is preferably 0.0001 to 10% by mass relative to the aqueous medium. It is more preferably 0.001% by mass or more, even more preferably 0.01% by mass or more, and particularly preferably 0.05% by mass or more, relative to the aqueous medium. It is also more preferably 5% by mass or less, even more preferably 3% by mass or less, and particularly preferably 1% by mass or less, relative to the aqueous medium.

[0414] The composition is preferably an aqueous solution containing a hydrocarbon surfactant and having a pH of 5.0 or higher, since this improves the stability of the polymerization and allows a TFE polymer with a higher molecular weight to be obtained. The pH of the aqueous solution is preferably 6.0 or higher, more preferably 6.5 or higher, even more preferably 7.0 or higher, particularly preferably 7.5 or higher, and particularly preferably 8.0 or higher. The upper limit of the pH is not particularly limited, but may be 12.0 or lower, or may be 11.0 or lower.

[0415] The hydrocarbon surfactant used in the above-mentioned addition step is preferably an anionic hydrocarbon surfactant, and more preferably a carboxylic acid type hydrocarbon surfactant. The anionic hydrocarbon surfactant and the carboxylic acid type hydrocarbon surfactant are not particularly limited, but for example, the compound (α) exemplified among the above-mentioned other compounds having surface activity can be suitably used.

[0416] The carboxylic acid type hydrocarbon surfactant used in the polymerization step and the addition step includes the surfactant (e) and surfactants represented by the above formula: R 6 (-LM)2 and anionic surfactants represented by the above formula: R 7 Among the anionic surfactants represented by (-LM)3, at least one selected from the group consisting of those having a carboxyl group (-COOH) or a group in which the hydrogen atom of the carboxyl group is substituted with an inorganic cation (e.g., a metal atom, ammonium, etc.), the above compound (α), the above surfactant (1-0A), and surfactants obtained by radical treatment or oxidation treatment of these surfactants is preferred. The above carboxylic acid type hydrocarbon surfactants may be used alone or as a mixture of two or more types. The compound (α) has the above-mentioned formula: R 102 -COOM(in the formula, R 102and M are the same as above.), as well as anionic surfactants represented by the above formula: RLM (wherein R, L, and M are the same as above), and surfactants (c) and (d) above which have a carboxyl group (—COOH) or a group in which the hydrogen atom of the carboxyl group is substituted with an inorganic cation (for example, a metal atom, ammonium, etc.).

[0417] The carboxylic acid type hydrocarbon surfactant is preferably the compound (α), and is preferably a compound represented by the formula (A1), a compound represented by the formula (c), c Ga-COOX c A compound represented by the formula (d) d Ga-COOX d A compound represented by the formula (e) e -COOM e and a compound represented by the above formula (1-0A) in which A is -COOM, and a compound obtained by subjecting these compounds to radical treatment or oxidation treatment, and further preferably at least one selected from the group consisting of a compound represented by the above formula (A1) and a compound obtained by subjecting these compounds to radical treatment or oxidation treatment. Particularly preferred is at least one selected from the group consisting of lauric acid, capric acid, myristic acid, pentadecylic acid, palmitic acid, salts thereof, and compounds obtained by radical treatment or oxidation treatment of these compounds. As the salts, those in which the hydrogen of the carboxyl group is bonded to a metal atom of the above-mentioned formula M, NR 101 4. Examples include, but are not limited to, imidazolium which may have a substituent, pyridinium which may have a substituent, or phosphonium which may have a substituent.

[0418] The above production method preferably involves polymerizing tetrafluoroethylene substantially in the absence of a fluorine-containing surfactant. In the above production method, "substantially in the absence of a fluorinated surfactant" means that the fluorinated surfactant is present at 10 ppm by mass or less relative to the aqueous medium, preferably 1 ppm by mass or less, more preferably 100 ppb by mass or less, even more preferably 10 ppb by mass or less, still more preferably less than 10 ppb by mass, still more preferably 1 ppb by mass or less, and particularly preferably less than 1 ppb by mass. "Substantially in the absence of a fluorine-containing surfactant" also means that no fluorine-containing surfactant is intentionally added.

[0419] The fluorine-containing surfactant may, for example, be an anionic fluorine-containing surfactant. The anionic fluorine-containing surfactant may be, for example, a surfactant containing fluorine atoms and having a total carbon number of 20 or less excluding the anionic group.

[0420] The fluorine-containing surfactant may also be a surfactant containing fluorine in the anionic moiety having a molecular weight of 1,000 or less, preferably 800 or less. The "anionic portion" refers to the portion of the fluorine-containing surfactant excluding the cation. For example, F(CF2) represented by the formula (I) below n1 In the case of COOM, "F(CF2) n1 The "COO" part.

[0421] Specific examples of the fluorine-containing surfactants include those described in U.S. Patent Application Publication Nos. 2007 / 0015864, 2007 / 0015865, 2007 / 0015866, 2007 / 0276103, 2007 / 0117914, 2007 / 142541, 2008 / 0015319, and U.S. Pat. No. 3,250,808. , U.S. Pat. No. 3,271,341, JP 2003-119204 A, WO 2005 / 042593, WO 2008 / 060461, WO 2007 / 046377, WO 2007 / 119526, WO 2007 / 046482, WO 2007 / 046345, U.S. Patent Application Publication No. 2014 / 0228531, WO 2013 / 189824, and WO 2013 / 189826.

[0422] The anionic fluorine-containing surfactants include those represented by the above-mentioned general formula (N 0 ) is an example of a compound represented by the formula:

[0423] As described above, examples of the anionic fluorine-containing surfactant include carboxylic acid-based fluorine-containing surfactants and sulfonic acid-based fluorine-containing surfactants.

[0424] The TFE polymer composition of the present disclosure can be suitably produced by a production method including an addition step of adding at least one selected from the group consisting of a radical scavenger and a decomposer of a polymerization initiator. The addition step is carried out during the above-mentioned emulsion polymerization step in an aqueous medium. The radical concentration during polymerization can be adjusted by adding a radical scavenger or a decomposer of a polymerization initiator. From the viewpoint of reducing the radical concentration, a radical scavenger is preferred.

[0425] The radical scavenger is a compound that does not have the ability to restart after addition or chain transfer to a free radical in the polymerization system. Specifically, a compound that easily undergoes a chain transfer reaction with a primary radical or a propagating radical to generate a stable radical that does not subsequently react with the monomer, or a compound that easily undergoes an addition reaction with a primary radical or a propagating radical to generate a stable radical, is used. Generally, the activity of what is called a chain transfer agent is characterized by the chain transfer constant and the reinitiation efficiency, but among chain transfer agents, those with a reinitiation efficiency of almost 0% are called radical scavengers. The radical scavenger can also be described as a compound whose chain transfer constant with TFE at the polymerization temperature is greater than the polymerization rate constant and whose reinitiation efficiency is substantially zero percent. "Reinitiation efficiency is substantially zero percent" means that the generated radicals turn the radical scavenger into stable radicals. Preferably, the compound has a chain transfer constant (Cs) with TFE at the polymerization temperature (=chain transfer rate constant (kc) / polymerization rate constant (kp)) of more than 0.1, and the compound has a chain transfer constant (Cs) of more preferably 0.5 or more, even more preferably 1.0 or more, even more preferably 5.0 or more, and particularly preferably 10 or more.

[0426] The radical scavenger in the present disclosure is preferably at least one selected from the group consisting of, for example, aromatic hydroxy compounds, aromatic amines, N,N-diethylhydroxylamine, quinone compounds, terpenes, thiocyanates, and cupric chloride (CuCl). Examples of aromatic hydroxy compounds include unsubstituted phenol, polyhydric phenol, salicylic acid, m- or p-salicylic acid, gallic acid, and naphthol. Examples of the unsubstituted phenol include o-, m-, or p-nitrophenol, o-, m-, or p-aminophenol, p-nitrosophenol, etc. Examples of the polyhydric phenol include catechol, resorcinol, hydroquinone, pyrogallol, phloroglucinol, naphthresorcinol, etc. Examples of aromatic amines include o-, m-, or p-phenylenediamine, benzidine, and the like. Examples of the quinone compound include o-, m-, or p-benzoquinone, 1,4-naphthoquinone, and alizarin. Examples of thiocyanates include ammonium thiocyanate (NH4SCN), potassium thiocyanate (KSCN), and sodium thiocyanate (NaSCN). Of the above radical scavengers, aromatic hydroxy compounds are preferred, unsubstituted phenols or polyhydric phenols are more preferred, and hydroquinone is even more preferred.

[0427] The amount of radical scavenger added is preferably an amount equivalent to 3 to 500% (molar basis) of the polymerization initiator concentration, from the viewpoint of reducing the standard specific gravity. A more preferred lower limit is 5% (molar basis), even more preferably 8% (molar basis), even more preferably 10% (molar basis), even more preferably 15% (molar basis), especially preferably 20% (molar basis), particularly preferably 25% (molar basis), especially preferably 30% (molar basis), especially preferably 35% (molar basis). A more preferred upper limit is 400% (molar basis), even more preferably 300% (molar basis), even more preferably 200% (molar basis), especially preferably 100% (molar basis).

[0428] The polymerization initiator decomposer may be any compound capable of decomposing the polymerization initiator used, and is preferably at least one selected from the group consisting of sulfites, bisulfites, bromates, diimines, diimine salts, oxalic acid, oxalates, copper salts, and iron salts. Examples of sulfites include sodium sulfite and ammonium sulfite. Examples of copper salts include copper(II) sulfate, and examples of iron salts include iron(II) sulfate. The amount of the polymerization initiator decomposer added is in the range of 25 to 300% by mass, preferably 25 to 150% by mass, and more preferably 50 to 100% by mass, based on the amount of the oxidizing agent combined as the polymerization initiator (redox initiator described below). The amount of decomposer for the polymerization initiator added is preferably an amount corresponding to 3 to 500% (molar basis) of the polymerization initiator concentration, from the viewpoint of reducing the standard specific gravity. A more preferred lower limit is 5% (molar basis), even more preferably 8% (molar basis), even more preferably 10% (molar basis), even more preferably 13% (molar basis), and even more preferably 15% (molar basis). A more preferred upper limit is 400% (molar basis), even more preferably 300% (molar basis), even more preferably 200% (molar basis), and especially preferably 100% (molar basis).

[0429] At least one selected from the group consisting of a radical scavenger and a decomposer of a polymerization initiator is preferably added when the concentration of the TFE polymer formed in the aqueous medium is 5% by mass or more, more preferably 10% by mass or more. It is also preferable to add the TFE polymer when the concentration of the TFE polymer formed in the aqueous medium is 40% by mass or less, more preferably 35% by mass or less, and even more preferably 30% by mass or less.

[0430] The adding step may be a step of continuously adding at least one selected from the group consisting of a radical scavenger and a decomposer for a polymerization initiator. Continuously adding at least one selected from the group consisting of radical scavengers and decomposers for polymerization initiators means, for example, adding at least one selected from the group consisting of radical scavengers and decomposers for polymerization initiators over time, without interruption, or in portions, rather than all at once.

[0431] The polymerization step may further comprise polymerizing tetrafluoroethylene in the presence of a nucleating agent.

[0432] The nucleating agent is preferably at least one selected from the group consisting of, for example, fluoropolyethers, nonionic surfactants, and chain transfer agents. In this case, the polymerization step is preferably a step of obtaining a TFE-based polymer by polymerizing tetrafluoroethylene in an aqueous medium in the presence of a hydrocarbon surfactant and the nucleating agent.

[0433] The fluoropolyether is preferably a perfluoropolyether.

[0434] The above fluoropolyether preferably has repeating units represented by formulas (1a) to (1d). (-CFCF3-CF2-O-) n (1a) (-CF2-CF2-CF2-O-) n (1b) (-CF2-CF2-O-) n -(-CF2-O-) m (1c) (-CF2-CFCF3-O-) n -(-CF2-O-) m (1d) (In formulas (1a) to (1d), m and n are integers of 1 or more.)

[0435] The fluoropolyether is preferably a fluoropolyether acid or its salt, and the fluoropolyether acid is preferably a carboxylic acid, a sulfonic acid, a sulfonamide, or a phosphonic acid, and more preferably a carboxylic acid. Among the fluoropolyether acids or their salts, the salt of a fluoropolyether acid is preferred, the ammonium salt of a fluoropolyether acid is more preferred, and the ammonium salt of a fluoropolyether carboxylic acid is even more preferred.

[0436] The fluoropolyether acids or salts thereof can have any chain structure in which oxygen atoms in the main chain of the molecule are separated by saturated fluorocarbon groups having 1 to 3 carbon atoms. Two or more types of fluorocarbon groups can be present in the molecule.

[0437] The fluoropolyether acid or salt thereof is selected from the group consisting of fluoropolyether acids and fluoropolyether salts having the following formula: CF3-CF2-CF2-O(-CFCF3-CF2-O-) n CFCF3-COOH, CF3-CF2-CF2-O(-CF2-CF2-CF2-O-) n -CF2-CF2COOH, or HOOC-CF2-O(-CF2-CF2-O-) n -(-CF2-O-) m CF2COOH (wherein m and n are the same as above.) or a salt thereof.

[0438] These structures are discussed by Kasai in J. Appl. Polymer Sci., 57, 797 (1995). As disclosed therein, such fluoropolyethers can have carboxylic acid groups or salts thereof at one or both ends. Similarly, such fluoropolyethers can have sulfonic or phosphonic acid groups or salts thereof at one or both ends. In addition, fluoropolyethers with acid functional groups at both ends can have different groups at each end. For monofunctional fluoropolyethers, the other end of the molecule is usually perfluorinated, but may contain hydrogen or chlorine atoms.

[0439] Fluoropolyethers having acid groups at one or both ends have at least two ether oxygens, preferably at least four ether oxygens, and even more preferably at least six ether oxygens. Preferably, at least one of the fluorocarbon groups separating the ether oxygens, more preferably at least two of such fluorocarbon groups, has 2 or 3 carbon atoms. Even more preferably, at least 50% of the fluorocarbon groups separating the ether oxygens have 2 or 3 carbon atoms. Also, preferably, the fluoropolyether has a total of at least 15 carbon atoms, and for example, the preferred minimum value of n or n + m in the above repeating unit structure is at least 5. Two or more fluoropolyethers having acid groups at one or both ends can be used in the method according to the present disclosure. Typically, unless special care is taken in the preparation of a single specific fluoropolyether compound, the fluoropolyether may contain multiple compounds in various proportions within the molecular weight range relative to the average molecular weight.

[0440] The fluoropolyether preferably has a number average molecular weight of 800 g / mol or more. Because the fluoropolyether acid or its salt may be difficult to disperse in an aqueous medium, the number average molecular weight is preferably less than 6000 g / mol. The fluoropolyether acid or its salt more preferably has a number average molecular weight of 800 to 3500 g / mol, and even more preferably 1000 to 2500 g / mol.

[0441] The amount of the fluoropolyether is preferably 5 to 3000 ppm, more preferably 5 to 2000 ppm, with a more preferred lower limit of 10 ppm and a more preferred upper limit of 100 ppm relative to the aqueous medium.

[0442] The nonionic surfactant as the nucleating agent may be any of the nonionic surfactants described above, and is preferably a nonionic surfactant that does not contain fluorine. For example, the nonionic surfactant may be a nonionic surfactant represented by the following general formula (i): R3 -OA 1 -H(i) (In the formula, R 3 is a linear or branched primary or secondary alkyl group having 8 to 18 carbon atoms, and A 1 is a polyoxyalkylene chain. R 3 The number of carbon atoms in R is preferably 10 to 16, and more preferably 12 to 16. 3 When the carbon number of R is 18 or less, good dispersion stability of the aqueous dispersion is easily obtained. 3 If the carbon number exceeds 18, the flow temperature is high and it is difficult to handle. 3 If the number of carbon atoms is less than 8, the surface tension of the aqueous dispersion increases, and the permeability and wettability tend to decrease.

[0443] The polyoxyalkylene chain may be composed of oxyethylene and oxypropylene. The polyoxyalkylene chain has an average repeat number of 5 to 20 oxyethylene groups and an average repeat number of 0 to 2 oxypropylene groups, and is a hydrophilic group. The number of oxyethylene units may include either a broad or narrow unimodal distribution, which is typically provided, or a broader or bimodal distribution obtained by blending. When the average repeat number of oxypropylene groups is greater than 0, the oxyethylene and oxypropylene groups in the polyoxyalkylene chain may be arranged in a block or random configuration. From the viewpoint of viscosity and stability of the aqueous dispersion, a polyoxyalkylene chain having an average repeat number of 7 to 12 oxyethylene groups and an average repeat number of 0 to 2 oxypropylene groups is preferred. 1 If the oxypropylene group has an average of 0.5 to 1.5, low foaming properties are favorable and it is preferable.

[0444] More preferably, R 3is (R')(R")HC-, where R' and R" are the same or different straight, branched, or cyclic alkyl groups having a total of at least 5, preferably 7 to 17, carbon atoms. Preferably, at least one of R' or R" is a branched or cyclic hydrocarbon group.

[0445] Specific examples of the polyoxyethylene alkyl ether include C 13 H 27 -O-(C2H4O) 10 -H, C 12 H 25 -O-(C2H4O) 10 -H, C 10 H 21 CH(CH3)CH2-O-(C2H4O)9-H, C 13 H 27 -O-(C2H4O)9-(CH(CH3)CH2O)-H, C 16 H 33 -O-(C2H4O) 10 -H, HC(CH 11 )(C7H 15 )-O-(C2H4O)9-H, etc. Examples of commercially available polyoxyethylene alkyl ethers include Genapol X080 (product name, manufactured by Clariant), the Noigen TDS series (manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) such as Noigen TDS-80 (trade name), the Leocol TD series (manufactured by Lion Chemical) such as Leocol TD-90 (trade name), the Lionol (registered trademark) TD series (manufactured by Lion Chemical), the T-Det A series (manufactured by Harcros Chemicals) such as T-Det A138 (trade name), and the Tergitol (registered trademark) 15S series (manufactured by Dow Chemical).

[0446] The nonionic surfactant is preferably an ethoxylate of 2,6,8-trimethyl-4-nonanol having an average of about 4 to about 18 ethylene oxide units, an ethoxylate of 2,6,8-trimethyl-4-nonanol having an average of about 6 to about 12 ethylene oxide units, or a mixture thereof. Nonionic surfactants of this type are also commercially available, for example, as TERGITOL TMN-6, TERGITOL TMN-10, and TERGITOL TMN-100X (all product names, manufactured by Dow Chemical).

[0447] The hydrophobic group of the nonionic surfactant may be any of an alkylphenol group, a linear alkyl group, and a branched alkyl group. For example, the polyoxyethylene alkylphenyl ether-based nonionic compound may be, for example, a compound represented by the following general formula (ii): R 4 -C6H4-OA 2 -H (ii) (In the formula, R 4 is a linear or branched primary or secondary alkyl group having 4 to 12 carbon atoms, and A 2 is a polyoxyalkylene chain.) Specific examples of the polyoxyethylene alkylphenyl ether-based nonionic compounds include Triton (registered trademark) X-100 (product name, manufactured by Dow Chemical Co.).

[0448] Other nonionic surfactants include difunctional block copolymers supplied by BASF as their Pluronic® R series, tridecyl alcohol alkoxylates supplied by BASF Corporation as their Iconol® TDA series, and hydrocarbon-containing siloxane surfactants, preferably hydrocarbon surfactants, wherein the hydrocarbyl groups, which may be substituted by halogens such as fluorine, are fully substituted by hydrogen atoms, whereby these siloxane surfactants can also be considered hydrocarbon surfactants, i.e., the monovalent substituents on the hydrocarbyl groups are hydrogen.

[0449] In the above production method, in addition to the specific hydrocarbon surfactant and other surface-active compounds used as desired, additives can be used to stabilize each compound, such as buffers, pH adjusters, stabilizing aids, and dispersion stabilizers.

[0450] The stabilizing aid is preferably paraffin wax, fluorine-based oil, fluorine-based solvent, silicone oil, etc. The stabilizing aid may be used alone or in combination of two or more. The stabilizing aid is more preferably paraffin wax. The paraffin wax may be liquid, semi-solid, or solid at room temperature, but is preferably a saturated hydrocarbon having 12 or more carbon atoms. The melting point of the paraffin wax is usually preferably 40 to 65°C, more preferably 50 to 65°C.

[0451] The amount of the stabilizing aid used is preferably 0.1 to 12 mass % based on the mass of the aqueous medium used, and more preferably 0.1 to 8 mass %. It is desirable that the stabilizing aid is sufficiently hydrophobic so that it is completely separated from the aqueous TFE polymer emulsion after emulsion polymerization of TFE and does not become a contaminating component.

[0452] In the above production method, emulsion polymerization can be carried out by charging an aqueous medium, the hydrocarbon surfactant, monomers, and other additives as necessary into a polymerization reactor, stirring the contents of the reactor, maintaining the reactor at a predetermined polymerization temperature, and then adding a predetermined amount of polymerization initiator to initiate the polymerization reaction. After the polymerization reaction has started, additional monomers, polymerization initiators, chain transfer agents, the surfactants, etc. may be added depending on the purpose. The hydrocarbon surfactant may also be added after the polymerization reaction has started.

[0453] In the emulsion polymerization, the polymerization temperature and polymerization pressure are appropriately determined depending on the type of monomer used, the molecular weight of the target TFE polymer, and the reaction rate. Usually, the polymerization temperature is 5 to 150°C, preferably 10°C or higher, more preferably 30°C or higher, and even more preferably 50°C or higher. Also, the polymerization temperature is more preferably 120°C or lower, and even more preferably 100°C or lower. The polymerization pressure is 0.05 to 10 MPaG. The polymerization pressure is more preferably 0.3 MPaG or more, and even more preferably 0.5 MPaG or more. The polymerization pressure is more preferably 5.0 MPaG or less, and even more preferably 3.0 MPaG or less. In particular, from the viewpoint of improving yield, the pressure is preferably 1.0 MPaG or higher, more preferably 1.2 MPaG or higher, even more preferably 1.5 MPaG or higher, still more preferably 1.8 MPaG or higher, and particularly preferably 2.0 MPaG or higher.

[0454] In the emulsion polymerization, the hydrocarbon surfactant is preferably added when the concentration of the TFE polymer formed in the aqueous medium is less than 0.60% by mass. More preferably, the concentration is 0.50% by mass or less, even more preferably 0.36% by mass or less, even more preferably 0.30% by mass or less, particularly preferably 0.20% by mass or less, and particularly preferably 0.10% by mass or less, and it is most preferable to add the surfactant at the start of polymerization. The above concentration is the concentration relative to the total of the aqueous medium and the TFE polymer. Furthermore, in the emulsion polymerization, the amount of hydrocarbon surfactant at the start of polymerization is preferably 1 ppm or more relative to the aqueous medium. The amount of hydrocarbon surfactant at the start of polymerization is preferably 10 ppm or more, more preferably 50 ppm or more, even more preferably 100 ppm or more, and even more preferably 200 ppm or more. There is no particular upper limit, but for example, it is preferably 100,000 ppm, and more preferably 50,000 ppm. By keeping the amount of hydrocarbon surfactant at the start of polymerization within the above range, an aqueous dispersion having a smaller average primary particle size and better stability can be obtained.

[0455] The polymerization initiator is not particularly limited as long as it can generate radicals within the polymerization temperature range, and known oil-soluble and / or water-soluble polymerization initiators can be used. Furthermore, polymerization can also be initiated as a redox reaction in combination with a reducing agent or the like. The concentration of the polymerization initiator is determined appropriately depending on the type of monomer, the molecular weight of the target TFE-based polymer, and the reaction rate.

[0456] As the polymerization initiator, an oil-soluble radical polymerization initiator or a water-soluble radical polymerization initiator can be used.

[0457] The oil-soluble radical polymerization initiator may be a known oil-soluble peroxide, and representative examples thereof include dialkyl peroxycarbonates such as diisopropyl peroxydicarbonate and di-sec-butyl peroxydicarbonate, peroxyesters such as t-butyl peroxyisobutyrate and t-butyl peroxypivalate, and dialkyl peroxides such as di-t-butyl peroxide.

[0458] The water-soluble radical polymerization initiator may be a known water-soluble peroxide, such as ammonium salts, potassium salts, or sodium salts of persulfuric acid, perborate, perchloric acid, perphosphoric acid, or percarbonate, t-butyl permaleate, or t-butyl hydroperoxide. A reducing agent such as sulfites or sulfites may also be contained, and the amount used may be 0.1 to 20 times the amount of the peroxide.

[0459] For example, when polymerization is carried out at low temperatures below 30°C, it is preferable to use a redox initiator, which combines an oxidizing agent and a reducing agent, as the polymerization initiator. Examples of oxidizing agents include persulfates, organic peroxides, potassium permanganate, manganese triacetate, cerium ammonium nitrate, and bromates. Examples of reducing agents include sulfites, bisulfites, bromates, diimines, and oxalic acid. Examples of persulfates include ammonium persulfate and potassium persulfate. Examples of sulfites include sodium sulfite and ammonium sulfite. To increase the decomposition rate of the initiator, it is also preferable to add a copper salt or an iron salt to the redox initiator combination. Examples of copper salts include copper(II) sulfate, and examples of iron salts include iron(II) sulfate.

[0460] As the redox initiator, it is preferred that the oxidizing agent is permanganic acid or a salt thereof, a persulfate, manganese triacetate, a cerium (IV) salt, or bromic acid or a salt thereof, and the reducing agent is a dicarboxylic acid or a salt thereof, or a diimine. More preferably, the oxidizing agent is permanganic acid or a salt thereof, persulfate, or bromic acid or a salt thereof, and the reducing agent is a dicarboxylic acid or a salt thereof.

[0461] Examples of the redox initiator include combinations of potassium permanganate / oxalic acid, potassium permanganate / ammonium oxalate, manganese triacetate / oxalic acid, manganese triacetate / ammonium oxalate, cerium ammonium nitrate / oxalic acid, and cerium ammonium nitrate / ammonium oxalate. When a redox initiator is used, either the oxidizing agent or the reducing agent may be charged into a polymerization vessel in advance, and then the other may be added continuously or intermittently to initiate polymerization. For example, when potassium permanganate / ammonium oxalate is used, it is preferable to charge ammonium oxalate into a polymerization vessel and then continuously add potassium permanganate thereto. In this specification, when the redox initiator is described as "potassium permanganate / ammonium oxalate," it means a combination of potassium permanganate and ammonium oxalate. The same applies to other compounds. As the redox initiator, it is preferable to use an oxidizing agent or reducing agent that can adjust the pH of the redox initiator aqueous solution to 4.0 or higher. The redox initiator aqueous solution refers to an aqueous solution of an oxidizing agent at a concentration of 0.50% by mass or an aqueous solution of a reducing agent at a concentration of 0.50% by mass. That is, it is sufficient that the pH of at least one of the 0.50 mass % aqueous solution of the oxidizing agent and the 0.50 mass % aqueous solution of the reducing agent is 4.0 or higher, and it is preferable that the pH of both the 0.50 mass % aqueous solution of the oxidizing agent and the 0.50 mass % aqueous solution of the reducing agent is 4.0 or higher. The pH of the redox initiator aqueous solution (0.50 mass % aqueous solution of oxidizing agent or 0.50 mass % aqueous solution of reducing agent) is more preferably 5.0 or higher, further preferably 5.5 or higher, and particularly preferably 6.0 or higher.

[0462] The redox initiator is particularly preferably a combination of an oxidizing agent that is a salt and a reducing agent that is a salt. For example, the oxidizing agent that is the salt is more preferably at least one selected from the group consisting of persulfates, permanganates, cerium (IV) salts, and bromates, further preferably permanganates, and particularly preferably potassium permanganate. Furthermore, the reducing agent which is the salt is more preferably at least one selected from the group consisting of oxalate, malonate, succinate, glutarate and bromate, further preferably oxalate, and particularly preferably ammonium oxalate.

[0463] Specifically, the redox initiator is preferably at least one selected from the group consisting of potassium permanganate / ammonium oxalate, potassium bromate / ammonium sulfite, manganese triacetate / ammonium oxalate, and cerium ammonium nitrate / ammonium oxalate, and more preferably at least one selected from the group consisting of potassium permanganate / ammonium oxalate, potassium bromate / ammonium sulfite, and cerium ammonium nitrate / ammonium oxalate.

[0464] By using a redox initiator in the polymerization step, the molecular weight of the resulting TFE-based polymer can be increased, which in turn reduces the SSG and makes the polymer stretchable. Furthermore, by using a redox initiator in the polymerization step, it is possible to increase the number of TFE polymer particles produced in the aqueous dispersion, and also to increase the yield of the TFE polymer. When a redox initiator is used, the oxidizing agent and the reducing agent may be added all at once at the beginning of the polymerization, or the reducing agent may be added all at once at the beginning of the polymerization and the oxidizing agent may be added continuously, or the oxidizing agent may be added all at once at the beginning of the polymerization and the reducing agent may be added continuously, or both the oxidizing agent and the reducing agent may be added continuously. When a redox initiator is used as the polymerization initiator, the amount of the oxidizing agent added is preferably 5 to 10,000 ppm, more preferably 10 to 1,000 ppm, and the amount of the reducing agent added is preferably 5 to 10,000 ppm, more preferably 10 to 1,000 ppm, relative to the aqueous medium. When a redox initiator is used in the polymerization step, the polymerization temperature is preferably 100° C. or lower, more preferably 95° C. or lower, and even more preferably 90° C. or lower. The polymerization temperature is preferably 10° C. or higher, more preferably 20° C. or higher, and even more preferably 30° C. or higher.

[0465] The amount of polymerization initiator added is not particularly limited, but may be added all at once, incrementally, or continuously at the beginning of polymerization in an amount (e.g., several ppm relative to the water concentration) that does not significantly decrease the polymerization rate. The upper limit is a range in which the reaction temperature can be increased while removing heat from the equipment using the heat of polymerization reaction, and a more preferred upper limit is a range in which the heat of polymerization reaction can be removed from the equipment. More specifically, for example, the amount is preferably 1 ppm or more relative to the aqueous medium, more preferably 10 ppm or more, and even more preferably 50 ppm or more. Also, the amount is preferably 100,000 ppm or less, more preferably 10,000 ppm or less, and even more preferably 5,000 ppm or less.

[0466] The aqueous medium is a reaction medium for polymerization and refers to a liquid containing water. The aqueous medium is not particularly limited as long as it contains water, and may contain water and, for example, a fluorine-free organic solvent such as an alcohol, ether, or ketone, and / or a fluorine-containing organic solvent having a boiling point of 40° C. or lower.

[0467] In the emulsion polymerization, a known chain transfer agent may be added depending on the purpose to adjust the polymerization rate and molecular weight.

[0468] Examples of the chain transfer agent include esters such as dimethyl malonate, diethyl malonate, methyl acetate, ethyl acetate, butyl acetate, and dimethyl succinate, as well as isopentane, methane, ethane, propane, isobutane, methanol, ethanol, isopropanol, acetone, various mercaptans, various halogenated hydrocarbons such as carbon tetrachloride, and cyclohexane.

[0469] Bromine compounds or iodine compounds may be used as chain transfer agents. Polymerization methods using bromine compounds or iodine compounds include, for example, a method of polymerizing fluoromonomers in an aqueous medium in the presence of a bromine compound or an iodine compound in a substantially oxygen-free state (iodine transfer polymerization method). Representative examples of the bromine compounds or iodine compounds used include, for example, compounds represented by the general formula: R a Ix Br y (wherein x and y are each an integer of 0 to 2 and satisfy 1≦x+y≦2; R a is a saturated or unsaturated fluorohydrocarbon group or chlorofluorohydrocarbon group having 1 to 16 carbon atoms, or a hydrocarbon group having 1 to 3 carbon atoms, which may contain an oxygen atom). By using a bromine compound or an iodine compound, iodine or bromine is introduced into the polymer and functions as a crosslinking point.

[0470] Examples of iodine compounds include 1,3-diiodoperfluoropropane, 2-iodoperfluoropropane, 1,3-diiodo-2-chloroperfluoropropane, 1,4-diiodoperfluorobutane, 1,5-diiodo-2,4-dichloroperfluoropentane, 1,6-diiodoperfluorohexane, 1,8-diiodoperfluorooctane, 1,12-diiodoperfluorododecane, 1,16-diiodoperfluorohexadecane, diiodomethane, 1,2-diiodoethane, 1,3-diiodo-n-propane, CF2Br2, BrCF2CF2Br, CF3CFBrCF2Br, CFClBr2, and BrCF2CFCl. Br, CFBrClCFClBr, BrCFCFCFBr, BrCFCFBrOCF, 1-bromo-2-iodoperfluoroethane, 1-bromo-3-iodoperfluoropropane, 1-bromo-4-iodoperfluorobutane, 2-bromo-3-iodoperfluorobutane, 3-bromo-4-iodoperfluorobutene-1, 2-bromo-4-iodoperfluorobutene-1, monoiodomonobromo-substituted benzene, diiodomonobromo-substituted benzene, and (2-iodoethyl) and (2-bromoethyl) substituted benzenes. These compounds may be used alone or in combination with each other.

[0471] Among these, it is preferable to use 1,4-diiodoperfluorobutane, 1,6-diiodoperfluorohexane, and 2-iodoperfluoropropane in terms of polymerization reactivity, crosslinking reactivity, availability, and the like.

[0472] The amount of the chain transfer agent used is usually 1 to 50,000 ppm, preferably 1 to 20,000 ppm, based on the total amount of fluoromonomers supplied.

[0473] The chain transfer agent may be added all at once to the reaction vessel before the initiation of polymerization, may be added all at once after the initiation of polymerization, may be added in multiple divided portions during the polymerization, or may be added continuously during the polymerization.

[0474] An aqueous dispersion of a TFE polymer can be obtained by step (A2). The aqueous dispersion usually contains a TFE polymer, compound (1) and / or (2), and an aqueous medium. The solids concentration of the aqueous dispersion is not limited, but may be, for example, 1.0 to 70% by mass. The solids concentration is preferably 8.0% by mass or more, more preferably 10.0% by mass or more, and is preferably 60.0% by mass or less, more preferably 50.0% by mass or less. In the above production method, the amount of adhesion is preferably 3.0% by mass or less, more preferably 2.0% by mass or less, more preferably 1.0% by mass or less, even more preferably 0.8% by mass or less, still more preferably 0.7% by mass or less, and particularly preferably 0.6% by mass or less, based on the finally obtained TFE-based polymer.

[0475] The coagulation in step (B) can be carried out by a known method. When coagulation is performed on the aqueous dispersion of the TFE polymer, the aqueous dispersion obtained by polymerization of a polymer latex or the like is usually diluted with water to a polymer concentration of 10 to 25% by mass (preferably 10 to 20% by mass), and the pH is adjusted to neutral or alkaline as needed, followed by stirring more vigorously than during the reaction in a vessel equipped with a stirrer. The coagulation may be performed while stirring while adding a coagulant such as a water-soluble organic compound such as methanol or acetone, an inorganic salt such as potassium nitrate or ammonium carbonate, or an inorganic acid such as hydrochloric acid, sulfuric acid, or nitric acid. The coagulation may also be performed continuously using an in-line mixer or the like.

[0476] The drying (heat treatment) in step (C) is usually carried out by using a vacuum, high frequency, hot air, or other means while the wet powder is kept in a state where it is not fluidized much, preferably kept stationary. Friction between powders, particularly at high temperatures, generally has an undesirable effect on fine powder TFE polymers. This is because particles made of this type of TFE polymer tend to easily fibrillate even with a small shear force, losing their original stable particle structure.

[0477] The drying temperature in step (C) is preferably 130°C or higher, more preferably 140°C or higher, even more preferably 150°C or higher, even more preferably 160°C or higher, even more preferably 180°C or higher, even more preferably 200°C or higher, particularly preferably 220°C or higher, and is preferably 300°C or lower, more preferably 280°C or lower, and even more preferably 250°C or lower, in order to more efficiently remove moisture and fluorine-containing compounds. When a vacuum is used, drying at a low temperature, for example, 60°C or higher, 70°C or higher, 80°C or higher, or 90°C or higher, is also preferred.

[0478] The drying time in step (C) is preferably 2 hours or more, more preferably 5 hours or more, even more preferably 10 hours or more, and even more preferably 15 hours or more, in order to more efficiently remove moisture and the fluorine-containing compound. The upper limit is not particularly limited, but is, for example, preferably 100 hours, more preferably 50 hours, and even more preferably 30 hours.

[0479] The air velocity in step (C) is preferably 0.01 m / s or more, more preferably 0.03 m / s or more, even more preferably 0.05 m / s or more, and even more preferably 0.1 m / s or more, from the viewpoint of more efficiently removing moisture and fluorine-containing compounds, and is preferably 50 m / s or less, more preferably 30 m / s or less, and even more preferably 10 m / s or less, from the viewpoint of suppressing scattering of powder.

[0480] The drying in step (C) can be carried out using an electric furnace or a steam furnace. For example, it can be carried out using an electric furnace such as a parallel-flow box-type electric furnace, a ventilated box-type electric furnace, a ventilated conveyor-type electric furnace, a band furnace, a radiant conveyor-type electric furnace, a fluidized-bed electric furnace, a vacuum electric furnace, an agitator-type electric furnace, an airflow-type electric furnace, or a hot-air circulation electric furnace, or a steam furnace corresponding to the above (an apparatus obtained by replacing the electric furnace in the apparatus name of each electric furnace with steam furnace). In terms of being able to remove moisture and fluorine-containing compounds more efficiently, a parallel-flow box-type electric furnace, a ventilated box-type electric furnace, a ventilated conveyor-type electric furnace, a band furnace, a fluidized-bed electric furnace, a hot-air circulation electric furnace, or a steam furnace corresponding to the above (an apparatus obtained by replacing the electric furnace in the apparatus name of each electric furnace with steam furnace) is preferred.

[0481] The drying in step (C) is preferably carried out by placing the wet powder in a container whose bottom and / or sides are breathable, since this allows for more efficient removal of moisture and the fluorine-containing compound. The container whose bottom and / or sides are breathable may be any container that can withstand the drying temperature, but is preferably made of a metal such as stainless steel. The container having breathable bottom and / or sides is preferably a tray (bat) having breathable bottom and / or sides, and more preferably a tray having a mesh bottom and / or sides (mesh tray). The mesh is preferably either a woven mesh or a punched metal. The mesh size is preferably 2000 μm or less (ASTM standard 10 mesh or more), more preferably 595 μm or less (30 mesh or more), even more preferably 297 μm or less (50 mesh or more), even more preferably 177 μm or less (80 mesh or more), particularly preferably 149 μm or less (100 mesh or more), and particularly preferably 74 μm or less (200 mesh or more). Also, 25 μm or more (500 mesh or less) is preferred. When the mesh is a woven net, the weaving method may be, for example, plain weave, twill weave, plain tatami weave, or twill tatami weave. When the mesh is a punched metal, the porosity is preferably 10% or more, more preferably 20% or more, and even more preferably 30% or more, and is preferably 95% or less.

[0482] In step (C), the amount of the wet powder to be placed is preferably 10 g / cm 3 in order to more efficiently remove moisture and fluorine-containing compounds. 2 Preferably, it is 8 g / cm or less. 2 More preferably, it is 5 g / cm or less. 2 More preferably, it is 3 g / cm or less. 2 It is particularly preferable that the density is 0.01 g / cm or less. 2 It is preferable that the concentration is 0.05 g / cm or more. 2 More preferably, it is 0.1 g / cm or more. 2 More preferably, it is equal to or greater than this.

[0483] The moisture content of the wet powder to be dried in step (C) is preferably 10% by mass or more, more preferably 20% by mass or more, and even more preferably 30% by mass or more, relative to the wet powder, in order to more efficiently remove moisture and the fluorine-containing compound, and is preferably 150% by mass or less, and more preferably 100% by mass or less.

[0484] In the above-mentioned production method, it is also preferable to carry out a treatment for reducing thermally induced discoloration of the TFE-based polymer. The treatment may be carried out on an aqueous dispersion of the TFE-based polymer, on a wet polymer after coagulation, on a polymer after drying, or a combination thereof.

[0485] Methods for reducing thermally induced discoloration include, for example, exposing aqueous dispersions of TFE-based polymers to oxidizing agents.

[0486] In the method of the present disclosure, the oxidizing agent is preferably an oxygen source. As used herein, "oxygen source" refers to any available chemical source of oxygen. "Available oxygen" refers to oxygen that can react as an oxidizing agent. The oxygen source utilized in accordance with the method of the present disclosure is preferably selected from the group consisting of air, oxygen-rich gas, ozone-containing gas, and hydrogen peroxide. "Oxygen-rich gas" refers to pure oxygen and gas mixtures containing more than about 21% oxygen by volume, preferably oxygen-enriched air. Preferably, oxygen-rich gas contains at least about 22% oxygen by volume. "Ozone-containing gas" refers to pure ozone and gas mixtures containing ozone, preferably ozone-enriched air. Preferably, the ozone content in the gas mixture is at least about 10 ppm ozone by volume.

[0487] One preferred oxygen source for practicing the method of the present disclosure is an ozone-containing gas. Another preferred oxygen source for practicing the method of the present disclosure is hydrogen peroxide. To expose the dispersion to an oxygen source, air, oxygen-rich gas, or ozone-containing gas can be injected into the dispersion continuously or intermittently (preferably in a stoichiometric excess) to provide an oxygen source during exposure to ultraviolet light. Hydrogen peroxide can also be added to the dispersion, preferably in a stoichiometric excess, by adding a hydrogen peroxide solution. The concentration of hydrogen peroxide is preferably about 0.1% to about 10% by weight, based on the TFE-based polymer solids content in the dispersion.

[0488] Exposure of the dispersion to an oxidizing agent can be accomplished by a variety of techniques. One preferred embodiment involves exposing the aqueous TFE-based polymer dispersion to ultraviolet light in the presence of an oxygen source. Depending on the equipment used, ultraviolet light exposure may be more effective on diluted dispersions in reducing discoloration. Therefore, to practice this embodiment, it is preferred that the aqueous TFE-based polymer dispersion is first diluted with water to a concentration less than that of the polymerized aqueous TFE-based polymer dispersion. A preferred concentration is about 2% to about 30% by weight, more preferably about 2% to about 20% by weight.

[0489] Ultraviolet light has a wavelength range or about 10 nm to about 400 nm, and is considered to have bands including UVA (315 nm to 400 nm), UVB (280 nm to 315 nm), and UVC (100 nm to 280 nm). Preferably, the ultraviolet light utilized has a wavelength in the UVC band.

[0490] Any of various types of ultraviolet lamps can be used as the ultraviolet light source. For example, submersible UV clarifier / sterilizer units sold for the purpose of controlling algae and bacterial growth in ponds are commercially available and can be used to implement this embodiment. These units include a low-pressure mercury UVC lamp in a water-circulating enclosure. The lamp is protected by a quartz tube so that water can circulate through the enclosure to be exposed to the ultraviolet light. This type of submersible UV clarifier / sterilizer unit is sold, for example, by Danner Manufacturing, Inc. of Islandia, NY under the brand name Pondmaster. For continuous processing, the dispersion can be circulated through this type of unit to expose the dispersion to the ultraviolet light. Single-pass or multi-pass processing can be used.

[0491] The dispersion can also be processed in a batch process in a container suitable for exposure to ultraviolet light in the presence of an oxygen source. In this embodiment, it is desirable to immerse a suitably protected ultraviolet lamp in the dispersion. For example, a container typically used for coagulating aqueous TFE-based polymer dispersions to produce TFE-based polymers can be used to practice the method of this embodiment by immersing an ultraviolet lamp in the dispersion held in the container. If desired, the dispersion can be circulated or stirred to facilitate exposure to ultraviolet light. When the oxygen source is a gas, as discussed below, circulation can be achieved or enhanced by injecting the oxygen source into the dispersion. Ultraviolet lamps equipped with protective quartz tubes of the type utilized in underwater UV clarifier / sterilizer units can be utilized for immersion in the dispersion after removal from the housing. Other ultraviolet lamps, such as medium-pressure mercury lamps, can also be used, provided that the lamp is suitably protected for immersion in the dispersion, such as by enclosing the lamp in a quartz photowell. Borosilicate glass photowells can also be used, but these may filter ultraviolet light in the UVC and UVB bands, reducing their effectiveness. Suitable medium pressure mercury vapor lamps are sold by Hanovia of Fairfield, New Jersey.

[0492] As used in this embodiment, "oxygen source" refers to any chemical source of available oxygen. "Available oxygen" refers to oxygen that can react as an oxidant. The oxygen source utilized in this embodiment is preferably selected from the group consisting of air, oxygen-rich gas, ozone-containing gas, and hydrogen peroxide. "Oxygen-rich gas" refers to pure oxygen and gas mixtures containing greater than about 21% oxygen by volume, preferably oxygen-enriched air. Preferably, oxygen-rich gas contains at least about 22% oxygen by volume. "Ozone-containing gas" refers to pure ozone and gas mixtures containing ozone, preferably ozone-enriched air. Preferably, the ozone content in the gas mixture is at least about 10 ppm ozone by volume.

[0493] One preferred oxygen source for the practice of this embodiment is an ozone-containing gas. Another preferred oxygen source for the practice of this embodiment is hydrogen peroxide. To ensure that an oxygen source is present in the dispersion during exposure to ultraviolet light, air, an oxygen-rich gas, or an ozone-containing gas can be injected into the dispersion continuously or intermittently (preferably in a stoichiometric excess) to provide an oxygen source during exposure to ultraviolet light. Hydrogen peroxide can also be added to the dispersion, preferably in a stoichiometric excess, by adding a hydrogen peroxide solution. The concentration of hydrogen peroxide is preferably about 0.1% to about 10% by weight, based on the TFE-based polymer solids content in the dispersion.

[0494] Ultraviolet light with an oxygen source is effective at ambient or mild temperatures, and therefore, elevated temperatures are typically not required to practice this embodiment. In a preferred form of this embodiment, the step of exposing the aqueous TFE-based polymer dispersion to ultraviolet light in the presence of an oxygen source is carried out at a temperature of from about 5° C. to about 70° C., preferably from about 15° C. to about 70° C.

[0495] The time period for which this embodiment is practiced will vary depending on factors including the power of the ultraviolet light used, the type of oxygen source, the processing conditions, etc. A preferred time period for this embodiment is from about 15 minutes to about 10 hours.

[0496] Another preferred embodiment includes exposing the aqueous TFE-based polymer dispersion to light having a wavelength of 10 nm to 760 nm in the presence of an oxygen source and a photocatalyst. Depending on the equipment used, light exposure may be more effective for diluted dispersions in reducing discoloration. Therefore, in practicing this embodiment, it is preferred that the aqueous TFE-based polymer dispersion be first diluted with water to a concentration lower than that of the polymerized aqueous TFE-based polymer dispersion. A preferred concentration is about 2% by weight to about 30% by weight, more preferably about 2% by weight to about 20% by weight.

[0497] The light utilized in accordance with this embodiment has a wavelength range of about 10 nm to about 760 nm. This wavelength range includes ultraviolet light, which has a wavelength range of about 10 nm to about 400 nm. Ultraviolet light has a wavelength range of about 10 nm to about 400 nm and is considered to have bands including UVA (315 nm to 400 nm), UVB (280 nm to 315 nm), and UVC (100 nm to 280 nm). Light utilized in accordance with this embodiment also includes visible light, which has a wavelength range of about 400 nm to about 760 nm.

[0498] Any of various types of lamps can be used as the light source. For example, submersible UV clarifier / sterilizer units sold for the purpose of controlling algae and bacterial growth in ponds are commercially available and can be used to implement this embodiment. These units include a low-pressure mercury UVC lamp in a water-circulating enclosure. The lamp is protected by a quartz tube so that water can circulate through the enclosure to be exposed to the ultraviolet light. This type of submersible UV clarifier / sterilizer unit is sold, for example, by Danner Manufacturing, Inc. of Islandia, NY under the brand name Pondmaster. For continuous processing, the dispersion can be circulated through this type of unit to expose it to the light. Single-pass or multi-pass processing can be used.

[0499] The dispersion can also be processed in a batch process in a container suitable for exposure to light in the presence of an oxygen source and a photocatalyst. In this embodiment, it is desirable to immerse a suitably protected lamp in the dispersion. For example, a container typically used for coagulating aqueous TFE-based polymer dispersions to produce TFE-based polymers can be used to practice the method of this embodiment by immersing a lamp in the dispersion held in the container. If desired, the dispersion can be circulated or stirred to facilitate exposure to light. When the oxygen source is a gas, as discussed below, circulation can be achieved or enhanced by injecting the oxygen source into the dispersion. Ultraviolet lamps equipped with protective quartz tubes of the type utilized in underwater UV clarifier / sterilizer units can be utilized for immersion in the dispersion after removal from their housings. Other ultraviolet lamps, such as medium-pressure mercury lamps, can also be used, provided that the lamp is suitably protected for immersion in the dispersion, such as by enclosing the lamp in a quartz photowell. Borosilicate glass photowells can also be used, but these may filter ultraviolet light in the UVC and UVB bands, reducing their effectiveness. Suitable medium pressure mercury vapor lamps are sold by Hanovia of Fairfield, New Jersey.

[0500] As used in this embodiment, "oxygen source" refers to any chemical source of available oxygen. "Available oxygen" refers to oxygen that can react as an oxidant. The oxygen source utilized in this embodiment is preferably selected from the group consisting of air, oxygen-rich gas, ozone-containing gas, and hydrogen peroxide. "Oxygen-rich gas" refers to pure oxygen and gas mixtures containing greater than about 21% oxygen by volume, preferably oxygen-enriched air. Preferably, oxygen-rich gas contains at least about 22% oxygen by volume. "Ozone-containing gas" refers to pure ozone and gas mixtures containing ozone, preferably ozone-enriched air. Preferably, the ozone content in the gas mixture is at least about 10 ppm ozone by volume.

[0501] One preferred oxygen source for the practice of this embodiment is an ozone-containing gas. Another preferred oxygen source for the practice of this embodiment is hydrogen peroxide. To provide an oxygen source in the dispersion during exposure to ultraviolet light, air, an oxygen-rich gas, or an ozone-containing gas can be injected into the dispersion continuously or intermittently (preferably in a stoichiometric excess) to provide an oxygen source during exposure to light. Hydrogen peroxide can also be added to the dispersion, preferably in a stoichiometric excess, by adding a hydrogen peroxide solution. The concentration of hydrogen peroxide is preferably about 0.1% to about 10% by weight, based on the TFE-based polymer solids content in the dispersion.

[0502] Any of a variety of photocatalysts can be used in the practice of this embodiment. Preferably, the photocatalyst is a heterogeneous photocatalyst. Most preferably, the heterogeneous photocatalyst is selected from the group consisting of titanium dioxide and zinc oxide. For example, titanium dioxide sold under the trade name Degussa P25, which has a primary particle size of 21 nm and is a mixture of 70% anatase and 30% rutile titanium dioxide, has been found to be an effective heterogeneous photocatalyst. Heterogeneous photocatalysts can be used by dispersing them in a dispersion prior to exposure to light. A preferred level of heterogeneous photocatalyst is from about 1 ppm to about 100 ppm based on the TFE-based polymer solids in the dispersion.

[0503] Light with an oxygen source and photocatalyst is effective at ambient or mild temperatures, and therefore, elevated temperatures are typically not required to practice this embodiment. In a preferred method according to this embodiment, the step of exposing the aqueous TFE-based polymer dispersion to ultraviolet light in the presence of an oxygen source is carried out at a temperature of from about 5°C to about 70°C, preferably from about 15°C to about 70°C.

[0504] The time period for which this embodiment is practiced will vary depending on factors including the power of the ultraviolet light used, the type of oxygen source, the processing conditions, etc. A preferred time period for this embodiment is from about 15 minutes to about 10 hours.

[0505] Another preferred embodiment includes a step of exposing the TFE-based polymer aqueous dispersion to hydrogen peroxide. To practice this embodiment, the TFE-based polymer aqueous dispersion is preferably first diluted with water to a concentration lower than the concentration of the polymerized TFE-based polymer aqueous dispersion. A preferred concentration is about 2% by weight to about 30% by weight, more preferably about 2% by weight to about 20% by weight.

[0506] The step of exposing the aqueous TFE polymer dispersion to hydrogen peroxide is preferably carried out by adding hydrogen peroxide to the aqueous TFE polymer dispersion, preferably in an amount of about 0.1% by mass to about 10% by mass based on the mass of the TFE polymer solids. Preferably, the step of exposing the aqueous TFE polymer dispersion to hydrogen peroxide is carried out at a temperature of about 10° C. to about 70° C., preferably about 25° C. to about 60° C. The time used for exposing the aqueous TFE polymer dispersion is preferably about 1 hour to about 48 hours.

[0507] It is also preferred for this embodiment to inject air, oxygen-rich gas, or ozone-containing gas into the TFE-based polymer dispersion during the step of exposing the TFE-based polymer aqueous dispersion to hydrogen peroxide. "Oxygen-rich gas" refers to a gas mixture containing more than about 21% oxygen by volume, preferably oxygen-enriched air, and pure oxygen. Preferably, oxygen-rich gas contains at least about 22% oxygen by volume. "Ozone-containing gas" refers to a gas mixture containing ozone, preferably ozone-enriched air, and pure ozone. Preferably, the ozone content in the gas mixture is at least about 10 ppm ozone by volume. The introduction of such a gas can be achieved by injecting the gas into the TFE-based polymer aqueous dispersion.

[0508] Preferably, the step of exposing the TFE-based polymer aqueous dispersion to hydrogen peroxide comprises exposing the TFE-based polymer aqueous dispersion to Fe +2 , Cu +1 or Mn +2 The reaction is carried out in the presence of Fe ions. +2 , Cu +1or Mn +2 The amount of ions is about 0.1 ppm to about 100 ppm based on the TFE-based polymer solids in the dispersion.

[0509] Although this method can be carried out in a continuous manner, a batch method is preferred because it is easy to control the time for exposing the TFE-based polymer aqueous dispersion to hydrogen peroxide to achieve the desired reduction in thermally induced discoloration.The batch method can be carried out in any suitable tank or vessel made of suitable materials and, if desired, can be heated to heat the dispersion during processing.For example, the batch method can be carried out in a vessel commonly used for coagulating TFE-based polymer aqueous dispersions, which typically has an impeller that can be used to stir the dispersion during processing.The dispersion can also be stirred by injecting air, oxygen-rich gas, or ozone-containing gas.

[0510] Another preferred embodiment includes exposing the TFE-based polymer aqueous dispersion to an oxidizing agent selected from the group consisting of hypochlorite and nitrite. To practice this embodiment, the TFE-based polymer aqueous dispersion is preferably first diluted with water to a concentration lower than that of the polymerized TFE-based polymer aqueous dispersion. A preferred concentration is about 2% to about 30% by weight, more preferably about 2% to about 20% by weight.

[0511] The step of exposing the aqueous TFE-based polymer dispersion to an oxidizing agent selected from the group consisting of hypochlorites and nitrites is preferably carried out by adding the oxidizing agent to the aqueous TFE-based polymer dispersion in an amount of about 0.05% to about 5% by weight, based on the weight of the TFE-based polymer solids. The preferred hypochlorites for addition to the dispersion are sodium hypochlorite or potassium hypochlorite. Sodium hypochlorite or potassium hypochlorite is preferably used in an amount of about 0.05% to about 5% by weight, based on the weight of the TFE-based polymer solids. However, if the aqueous medium of the dispersion is sufficiently alkaline, for example by containing sodium hydroxide, hypochlorite can also be generated in situ by injecting chlorine gas into the dispersion. The preferred nitrites for addition to the dispersion are sodium nitrite, potassium nitrite, and ammonium nitrite. Sodium nitrite, potassium nitrite, and ammonium nitrite are preferably used in an amount of about 0.5% to about 5% by weight, based on the weight of the TFE-based polymer solids.

[0512] Preferably, the step of exposing the TFE-based polymer aqueous dispersion to the oxidizing agent is carried out at a temperature of about 10° C. to about 70° C. The exposure time to the TFE-based polymer aqueous dispersion is preferably about 5 minutes to about 3 hours.

[0513] It is also preferred for this embodiment to introduce air, oxygen-rich gas, or ozone-containing gas into the TFE-based polymer dispersion during the step of exposing the TFE-based polymer aqueous dispersion to an oxidizing agent. "Oxygen-rich gas" refers to a gas mixture containing more than about 21% oxygen by volume, preferably oxygen-enriched air, and pure oxygen. Preferably, oxygen-rich gas contains at least about 22% oxygen by volume. "Ozone-containing gas" refers to a gas mixture containing ozone, preferably ozone-enriched air, and pure ozone. Preferably, the ozone content in the gas mixture is at least about 10 ppm ozone by volume. The introduction of such gases can be achieved by injecting such gases into the TFE-based polymer aqueous dispersion.

[0514] Although this embodiment can also be carried out in a continuous method, batch method is preferred because in batch method, it is easy to control the exposure time of hypochlorite or nitrite and TFE-based polymer aqueous dispersion to achieve the desired reduction of thermally induced discoloration.Batch method can be carried out in any suitable tank or container that is made of suitable construction material and can be heated if necessary to heat dispersion during processing.For example, batch method can be carried out in the container that is usually used for coagulating TFE-based polymer aqueous dispersion, which is typically equipped with an impeller that can be used to stir dispersion during processing.It is also possible to use the injection of air, oxygen-rich gas or ozone-containing gas to stir dispersion.

[0515] Another preferred embodiment includes adjusting the pH of the aqueous medium of the TFE-based polymer aqueous dispersion to greater than about 8.5 and exposing the TFE-based polymer aqueous dispersion to an oxygen source. To practice this embodiment, the TFE-based polymer aqueous dispersion is preferably first diluted with water to a concentration lower than that of the polymerized TFE-based polymer aqueous dispersion. A preferred concentration is about 2% to about 30% by weight, more preferably about 2% to about 20% by weight.

[0516] The pH of the TFE-based polymer aqueous dispersion is preferably adjusted to about 8.5 to about 11. More preferably, the pH of the aqueous medium of the TFE-based polymer aqueous dispersion is adjusted to about 9.5 to about 10.

[0517] In the practice of this embodiment, the pH can be adjusted by adding a base that is sufficiently strong enough to adjust the pH of the aqueous TFE-based polymer dispersion to the desired level and that is otherwise compatible with the processing of the dispersion and the final use properties of the resulting TFE-based polymer. Preferred bases are alkali metal hydroxides such as sodium hydroxide or potassium hydroxide. Ammonium hydroxide can also be used.

[0518] As used in this embodiment, "oxygen source" refers to any chemical source of available oxygen. "Available oxygen" refers to oxygen that can react as an oxidant. The oxygen source utilized in this embodiment is preferably selected from the group consisting of air, oxygen-rich gas, ozone-containing gas, and hydrogen peroxide. "Oxygen-rich gas" refers to pure oxygen and gas mixtures containing greater than about 21% oxygen by volume, preferably oxygen-enriched air. Preferably, oxygen-rich gas contains at least about 22% oxygen by volume. "Ozone-containing gas" refers to pure ozone and gas mixtures containing ozone, preferably ozone-enriched air. Preferably, the ozone content in the gas mixture is at least about 10 ppm ozone by volume.

[0519] For the practice of this embodiment, one preferred oxygen source is an ozone-containing gas. Another preferred oxygen source for the practice of this embodiment is hydrogen peroxide. To expose the dispersion to the oxygen source, air, oxygen-rich gas, or ozone-containing gas can be injected into the dispersion continuously or intermittently (preferably in a stoichiometric excess). Hydrogen peroxide can also be added to the dispersion, preferably in a stoichiometric excess, by adding a hydrogen peroxide solution. The concentration of hydrogen peroxide is preferably about 0.1% to about 10% by weight, based on the TFE-based polymer solids content in the dispersion.

[0520] Preferably, the step of exposing the aqueous TFE polymer dispersion to the oxygen source is carried out at a temperature of from about 10° C. to about 95° C., more preferably from about 20° C. to about 80° C., and most preferably from about 25° C. to about 70° C. The time utilized for exposing the aqueous TFE polymer dispersion to the oxygen source is preferably from about 5 minutes to about 24 hours.

[0521] Although this method can be carried out in a continuous manner, a batch method is preferred because it is easy to control the time for exposing the TFE-based polymer aqueous dispersion to hydrogen peroxide to achieve the desired reduction in thermally induced discoloration.The batch method can be carried out in any suitable tank or vessel made of suitable materials and, if desired, can be heated to heat the dispersion during processing.For example, the batch method can be carried out in a vessel commonly used for coagulating TFE-based polymer aqueous dispersions, which typically has an impeller that can be used to stir the dispersion during processing.The dispersion can also be stirred by injecting air, oxygen-rich gas, or ozone-containing gas.

[0522] Another preferred method for reducing thermally induced discoloration is to contact an aqueous dispersion of a TFE-based polymer with an adsorbent.

[0523] The term "sorbent" refers to a material capable of removing compounds, such as hydrocarbon surfactants, that cause thermally induced discoloration of TFE-based polymers upon contact with aqueous dispersions of TFE-based polymers. Adsorbents useful in practicing the methods of the present disclosure can be in any of a variety of physical forms, such as particles or larger structures with porosity that provide sufficient surface area to be effective as adsorbents. The term adsorbent is not intended to be limited in any way by mechanism or mode of operation; adsorbents can operate by adsorption, absorption, or other mechanisms that achieve removal of compounds that cause thermally induced discoloration of TFE-based polymers upon contact with aqueous dispersions of TFE-based polymers.

[0524] The adsorbent is preferably in the form of particles, which provides increased surface area. This is because increased surface area generally increases the adsorbent's adsorption rate and / or ability to adsorb color-forming compounds. Particulate adsorbents can have any shape, such as beads, spheres, cylinders, rods, etc., and can also include mixtures of such shapes. The adsorbent particles are preferably porous to further increase surface area. Porous particles allow for the use of larger particle sizes, which facilitates handling and use as an adsorbent. Depending on the type of adsorbent and the porosity of the particles, particle size can vary, but preferably ranges from about 0.05 mm to about 20 mm in number average particle diameter. Depending on the type, the surface area of ​​the adsorbent can vary widely, but is preferably about 10 m 2 / g~about 3000m 2 / g range.

[0525] Adsorbents useful in carrying out the method of the present disclosure include activated carbon, ion exchange resins, silica gel, polymeric adsorbents, diatomaceous earth, zeolites, clay, and bonded silica.Preferred adsorbents are activated carbon, ion exchange resins, silica gel, polymeric adsorbents, diatomaceous earth, and zeolites.A particularly preferred adsorbent is activated carbon.Another particularly preferred adsorbent is ion exchange resins.

[0526] Activated carbon is available in a variety of forms, including powder, granules, and extruded forms (extruded activated carbon contains a binder to form the particles into a larger shape). Granular activated carbons sold for use in water treatment applications are suitable for use in practicing the methods of the present disclosure. Suitable granular activated carbons are, for example, Calgon DSR-C8X30 and Calgon Filtrasorb® 400, available from Calgon Carbon Corporation of Pittsburgh, Pennsylvania.

[0527] Ion exchange resins, especially anion exchange resins, can be particularly effective when anionic hydrocarbon surfactants that cause thermally induced discoloration are present in the fluoropolymer dispersion. Useful anion exchange resins include strong-base and weak-base anion exchange resins. Suitable weak-base anion exchange resins contain primary, secondary, or tertiary amine groups. Suitable strong-base anion exchange resins contain quaternary ammonium groups. Weak-base resins are useful because they are easy to regenerate, while strong-base resins can reduce discoloration-causing compounds and increase resin utilization. Strong-base anion exchange resins also have the advantage of being less sensitive to the pH of the medium. Strong-base anion exchange resins have an associated counterion, typically available in the chloride or hydroxyl form, but can be easily converted to other forms as needed. Examples of suitable commercially available strong base anion exchange resins having quaternary ammonium groups with trimethylamine moieties include Dowex® 550A, Siemens A-464-OH, Sybron M-500-OH, Sybron ASB1-OH, Purolite A-500-OH, Itochu TSA 1200, and Amberlite® IR 402. Examples of suitable commercially available strong base anion exchange resins having quaternary ammonium groups with dimethylethanolamine moieties include Siemens A-244-OH, Amberlite® 410, Dowex® Marathon A2, and Dowex® Upcore Mono A2.

[0528] Silica gel suitable for practicing the methods of the present disclosure is commercially available. One example is Grace Davison Grade 408 silica gel, available from Grace Davison, Baltimore, Maryland.

[0529] Polymeric adsorbents useful in practicing the disclosed method are highly porous polymeric resin beads with an internal surface capable of adsorbing compounds that cause thermally induced discoloration. Various polymers, such as styrene divinylbenzene, ethylene dimethacrylate, and methacrylate styrene, are used as polymeric adsorbents. Examples of suitable polymeric adsorbents include Amberlite® XAD-2, Amberlite® XAD-16, and Amberlite® XAD-1180, available from Dow Chemical, Midland, Michigan.

[0530] Diatomaceous earth suitable for carrying out the methods of the present disclosure is commercially available in various forms, including diatomaceous earth sold as a coarse filter aid, such as Celite® 545, available from Sigma Aldrich, St. Louis, Missouri.

[0531] Zeolites are microporous aluminosilicate minerals commonly used as commercial adsorbents. They are also known as "molecular sieves" due to their ability to selectively separate molecules primarily based on a size exclusion process. Commercially available zeolites are suitable for practicing the methods of the present disclosure, such as Grace Davison Zeolite A, available from Grace Davison, Baltimore, Maryland.

[0532] When carrying out the method of the present disclosure, the solids content of the aqueous fluoropolymer dispersion during contact with the adsorbent is preferably about 2% to about 60% by weight. It may be advantageous to dilute the as-polymerized dispersion with water to a concentration lower than that of the as-polymerized aqueous TFE-based polymer dispersion. A preferred concentration is about 2% to about 30% by weight, more preferably about 2% to about 20% by weight.

[0533] Preferably, the contact between the aqueous TFE polymer dispersion and the adsorbent is carried out at a temperature of about 5°C to about 80°C. The temperature used will vary depending on the type of adsorbent used. For example, activated carbon is particularly effective at temperatures close to room temperature, i.e., about 10 to about 30°C. Ion exchange membranes can be operated at slightly higher temperatures, i.e., about 50 to about 70°C, to increase the sorption rate.

[0534] In one embodiment, the method of the present disclosure is carried out by contacting the aqueous TFE-based polymer dispersion with the adsorbent by mixing the adsorbent with the aqueous TFE-based polymer dispersion and then separating the adsorbent from the dispersion. For example, a stirred tank containing a slurry of the dispersion and adsorbent can be used to contact the adsorbent with the dispersion, followed by filtration to remove the adsorbent. It is desirable to use enough adsorbent so that the contact time is practical, for example, from about 5 minutes to about 4 hours.

[0535] According to a preferred embodiment of the method of the present disclosure, the contact between the aqueous TFE-based polymer dispersion and the adsorbent is carried out by passing the aqueous TFE-based polymer dispersion through an adsorbent bed. For example, a column packed with the adsorbent can be used as a fixed bed. The column can be used to allow gravity flow of the dispersion, or the dispersion can be pumped upward or downward through the column as needed. If necessary, multiple passes through the column can be made.

[0536] For dispersions stabilized solely by hydrocarbon surfactant, which is removed by a sorbent, it is preferred that the sorbent not remove so much hydrocarbon surfactant that the dispersion becomes unstable and coagulates prematurely.

[0537] Another preferred method for reducing thermally induced discoloration is post-treating the TFE-based polymer by exposing it to an oxidizing agent. The additive effect of combining this post-treatment with the step of exposing the aqueous dispersion to an oxidizing agent or contacting it with an adsorbent can provide an improvement over the reduction in thermally induced discoloration achieved by exposing the aqueous dispersion to an oxidizing agent or contacting it with an adsorbent alone.

[0538] Post-treatment of TFE-based polymers can be accomplished by a variety of techniques. A preferred post-treatment involves exposing the TFE-based polymer to fluorine. While fluorine exposure can be accomplished with a variety of fluorine radical-generating compounds, the TFE-based polymer is preferably exposed by contacting the TFE-based polymer with fluorine gas. Because the reaction with fluorine is highly exothermic, it is preferable to dilute the fluorine with an inert gas such as nitrogen. The level of fluorine in the fluorine / inert gas mixture can range from 1 to 100% by volume, but is preferably about 5 to about 25% by volume due to the high hazards of working with pure fluorine. For TFE-based polymers that exhibit severe thermally induced discoloration, the fluorine / inert gas mixture should be sufficiently diluted to prevent overheating of the TFE-based polymer and the associated fire hazards.

[0539] Heating the TFE-based polymer during exposure to fluorine enhances the reaction rate. Because the reaction of fluorine to reduce thermally induced discoloration is highly exothermic, some or all of the desired heating may be provided by a reaction involving fluorine. This post-treatment can be carried out on a TFE-based polymer that has been heated to a temperature above the melting point of the TFE-based polymer or below the melting point of the TFE-based polymer.

[0540] For processes carried out below the melting point, the step of exposing the TFE-based polymer to fluorine is preferably carried out with the TFE-based polymer heated to a temperature of about 20°C to about 250°C. In one embodiment, the temperature utilized is about 150°C to about 250°C. In another embodiment, the temperature is about 20°C to about 100°C. For PTFE resins (including modified PTFE resins) that are not melt-processable, i.e., PTFE fine powder, it is preferred to carry out the process at a temperature below the melting point of the PTFE resin to prevent sintering and melting of the resin. Preferably, the PTFE fine powder resin is heated to a temperature below about 200°C to prevent adverse effects on the end-use characteristics of the PTFE resin. In one preferred embodiment, the temperature is about 20°C to about 100°C.

[0541] For TFE-based polymers that are melt-processible, the method can be carried out with the TFE-based polymer heated to a temperature below or above the melting point of the TFE-based polymer. Preferably, the method for melt-processible resins is carried out with the TFE-based polymer heated to a temperature above its melting point. Preferably, the step of exposing the TFE-based polymer to fluorine is carried out with the TFE-based polymer heated to a temperature above its melting temperature up to about 400°C.

[0542] For the processing involving TFE-based polymers heated ...

Claims

1. A tetrafluoroethylene-based polymer composition used in a binder for an electrochemical device, the composition comprising a tetrafluoroethylene-based polymer which is a copolymer of tetrafluoroethylene and a monomer having a polar group, and having fibrillation ability, the monomer having a polar group is a non-fluorine-containing monomer having a polar group, the content of the monomer unit having a polar group is 0.0001 to 1.0% by mass based on the total polymerized units; the monomer having a polar group is at least one selected from the group consisting of a non-fluorine-containing monomer having a carboxyl group, a non-fluorine-containing monomer having a sulfo group, and a monomer represented by the following general formula (10): A tetrafluoroethylene polymer composition, wherein the monomer represented by the general formula (10) is at least one selected from the group consisting of a monomer represented by the following formula (10-1), a monomer represented by the following formula (10-2), a monomer represented by the following formula (10-3), and a monomer represented by the following formula (10-4): General formula (10): CH ２ =CR １１ -L １１ -R １２ (In the formula, R １１ represents a hydrogen atom or an alkyl group. １１ represents a single bond, -CO-O-*, -O-CO-* or -O-. * represents R １２ represents the bonding position with １２ represents a hydrogen atom, an alkyl group, or a nitrile group. Formula (10-1) CH 2 =CR 11 -CO-O-R 13 Formula (10-2) CH 2 =CR 11 -O-CO-R 14 Formula (10-3) CH 2 =CR 11 -OR 15 Formula (10-4) CH 2 =CR 11 -R 16 (In the formula, R 11 is defined as above. R 13 represents a hydrogen atom or an alkyl group. R 14 represents an alkyl group. R 15 represents an alkyl group. R 16 represents a nitrile group.)

2. The tetrafluoroethylene polymer composition according to claim 1, wherein the monomer having a polar group is at least one selected from the group consisting of a non-fluorinated monomer having a carboxyl group, a non-fluorinated monomer having a sulfo group, and a monomer represented by the following formula (10-1): CH ２ =CR １１ -CO-O-R １３ (10-1) (In the formula, R １１ is a hydrogen atom or an alkyl group, and R １３ is a hydrogen atom or an alkyl group.

3. 3. The tetrafluoroethylene polymer composition according to claim 1, in the form of a powder.

4. 3. The tetrafluoroethylene polymer composition according to claim 1, which is used as a binder for lithium ion secondary batteries and is in the form of a powder.

5. A binder for electrochemical devices consisting essentially of a tetrafluoroethylene-based polymer composition, the tetrafluoroethylene-based polymer composition containing a tetrafluoroethylene-based polymer which is a copolymer of tetrafluoroethylene and a monomer having a polar group, and having fibrillating ability; the monomer having a polar group is a non-fluorine-containing monomer having a polar group, the content of the monomer unit having a polar group is 0.0001 to 1.0% by mass based on the total polymerized units; the monomer having a polar group is at least one selected from the group consisting of a non-fluorine-containing monomer having a carboxyl group, a non-fluorine-containing monomer having a sulfo group, and a monomer represented by the following general formula (10): The binder for electrochemical devices, wherein the monomer represented by the general formula (10) is at least one selected from the group consisting of a monomer represented by the following formula (10-1), a monomer represented by the following formula (10-2), a monomer represented by the following formula (10-3), and a monomer represented by the following formula (10-4): General formula (10): CH ２ =CR １１ -L １１ -R １２ (In the formula, R １１ represents a hydrogen atom or an alkyl group. １１ represents a single bond, -CO-O-*, -O-CO-* or -O-. * represents R １２ represents the bonding position with １２ represents a hydrogen atom, an alkyl group, or a nitrile group. Formula (10-1) CH 2 =CR 11 -CO-O-R 13 Formula (10-2) CH 2 =CR 11 -O-CO-R 14 Formula (10-3) CH 2 =CR 11 -OR 15 Formula (10-4) CH 2 =CR 11 -R 16 (In the formula, R 11 is defined as above. R 13 represents a hydrogen atom or an alkyl group. R 14 represents an alkyl group. R 15 represents an alkyl group. R 16 represents a nitrile group.)

6. 6. The binder for electrochemical devices according to claim 5, wherein the tetrafluoroethylene polymer composition has an endothermic peak temperature of 327°C or higher and 350°C or lower.

7. 7. The binder for electrochemical devices according to claim 5, wherein the standard specific gravity of the tetrafluoroethylene polymer composition is 2.280 or less.

8. 7. The binder for electrochemical devices according to claim 5, wherein the 1.0% mass loss temperature of the tetrafluoroethylene-based polymer composition is 492°C or lower.

9. 7. The binder for electrochemical devices according to claim 5, wherein the tetrafluoroethylene polymer composition has a thermal stability index (TII) of 20 or more.

10. The tetrafluoroethylene-based polymer composition further contains a fluorine-containing compound having a hydrophilic group, The hydrophilic group is —SO ３ M ａ , -SO ２ M ａ , -OSO ２ M ａ , -PO ３ M ａ , -COOM ａ , -OCOM ａ , and -OM ａ (In the formula, M ａ is —H, a metal atom, —NR ２ ４ , optionally substituted imidazolium, optionally substituted pyridinium, or optionally substituted phosphonium, and R ２ 7. The binder for electrochemical devices according to claim 5, wherein the binder is at least one selected from the group consisting of:

11. 7. The binder for electrochemical devices according to claim 5, wherein the tetrafluoroethylene-based polymer composition contains a compound represented by the following general formula (1): General formula (1): (H-(CF) ２ ) ｍ－１ -COO) ｐ M １ (wherein m is 4 to 20. M １ represents H, a metal atom, NR ５ ４ (R ５ may be the same or different and are H or an organic group having 1 to 10 carbon atoms), an imidazolium which may have a substituent, a pyridinium which may have a substituent, or a phosphonium which may have a substituent; and p is 1 or 2.

12. 7. The binder for electrochemical devices according to claim 5, wherein the tetrafluoroethylene polymer composition contains a compound represented by the following general formula (2): General formula (2): (H-(CF) ２ ) ｎ -SO ３ ) ｑ M ２ (wherein n is 4 to 20. M ２ is H, metal atom, NR ５ ４ (R ５ is the same as above), optionally substituted imidazolium, optionally substituted pyridinium, or optionally substituted phosphonium. q is 1 or 2.

13. 7. The binder for electrochemical devices according to claim 5, wherein the tetrafluoroethylene polymer composition is substantially free of a compound represented by the following general formula (3): General formula (3): (H-(CF) ２ ) ８ -SO ３ ) ｑ M ２ (In the formula, M ２ is H, metal atom, NR ５ ４ (R ５ may be the same or different and are H or an organic group having 1 to 10 carbon atoms), an imidazolium which may have a substituent, a pyridinium which may have a substituent, or a phosphonium which may have a substituent; and q is 1 or 2.

14. 7. The binder for electrochemical devices according to claim 5, wherein the monomer having a polar group is at least one selected from the group consisting of a non-fluorinated monomer having a carboxyl group, a non-fluorinated monomer having a sulfo group, and a monomer represented by the following formula (10-1): CH ２ =CR １１ -CO-O-R １３ (10-1) (In the formula, R １１ is a hydrogen atom or an alkyl group, and R １３ is a hydrogen atom or an alkyl group.

15. 7. The binder for electrochemical devices according to claim 5 or 6, which is a binder for lithium ion secondary batteries and is in the form of powder.

16. A tetrafluoroethylene-based polymer composition used in a binder for an electrochemical device, the composition comprising a tetrafluoroethylene-based polymer which is a copolymer of tetrafluoroethylene and a monomer having a polar group, the composition having a fibrillated portion, and an endothermic peak temperature of 327°C or higher and 350°C or lower, the monomer having a polar group is a non-fluorine-containing monomer having a polar group, the content of the monomer unit having a polar group is 0.0001 to 1.0% by mass based on the total polymerized units; the monomer having a polar group is at least one selected from the group consisting of a non-fluorine-containing monomer having a carboxyl group, a non-fluorine-containing monomer having a sulfo group, and a monomer represented by the following general formula (10): A tetrafluoroethylene polymer composition, wherein the monomer represented by the general formula (10) is at least one selected from the group consisting of a monomer represented by the following formula (10-1), a monomer represented by the following formula (10-2), a monomer represented by the following formula (10-3), and a monomer represented by the following formula (10-4): General formula (10): CH ２ =CR １１ -L １１ -R １２ (In the formula, R １１ represents a hydrogen atom or an alkyl group. １１ represents a single bond, -CO-O-*, -O-CO-* or -O-. * represents R １２ represents the bonding position with １２ represents a hydrogen atom, an alkyl group, or a nitrile group. Formula (10-1) CH 2 =CR 11 -CO-O-R 13 Formula (10-2) CH 2 =CR 11 -O-CO-R 14 Formula (10-3) CH 2 =CR 11 -OR 15 Formula (10-4) CH 2 =CR 11 -R 16 (In the formula, R 11 is defined as above. R 13 represents a hydrogen atom or an alkyl group. R 14 represents an alkyl group. R 15 represents an alkyl group. R 16 represents a nitrile group.)

17. The tetrafluoroethylene polymer composition according to claim 16, wherein the monomer having a polar group is at least one selected from the group consisting of a fluorine-free monomer having a carboxyl group, a fluorine-free monomer having a sulfo group, and a monomer represented by the following formula (10-1): CH ２ =CR １１ -CO-O-R １３ (10-1) (In the formula, R １１ is a hydrogen atom or an alkyl group, and R １３ is a hydrogen atom or an alkyl group.

18. The tetrafluoroethylene polymer composition according to claim 16 or 17, which is used as a binder for lithium ion secondary batteries and is in the form of a sheet.

19. A binder for electrochemical devices consisting essentially of a tetrafluoroethylene-based polymer composition, wherein the tetrafluoroethylene-based polymer composition contains a tetrafluoroethylene-based polymer which is a copolymer of tetrafluoroethylene and a monomer having a polar group, has fibrillated portions, and has an endothermic peak temperature of 327°C or higher and 350°C or lower; the monomer having a polar group is a non-fluorine-containing monomer having a polar group, the content of the monomer unit having a polar group is 0.0001 to 1.0% by mass based on the total polymerized units; the monomer having a polar group is at least one selected from the group consisting of a non-fluorine-containing monomer having a carboxyl group, a non-fluorine-containing monomer having a sulfo group, and a monomer represented by the following general formula (10): The binder for electrochemical devices, wherein the monomer represented by the general formula (10) is at least one selected from the group consisting of a monomer represented by the following formula (10-1), a monomer represented by the following formula (10-2), a monomer represented by the following formula (10-3), and a monomer represented by the following formula (10-4): General formula (10): CH ２ =CR １１ -L １１ -R １２ (In the formula, R １１ represents a hydrogen atom or an alkyl group. １１ represents a single bond, -CO-O-*, -O-CO-* or -O-. * represents R １２ represents the bonding position with １２ represents a hydrogen atom, an alkyl group, or a nitrile group. Formula (10-1) CH 2 =CR 11 -CO-O-R 13 Formula (10-2) CH 2 =CR 11 -O-CO-R 14 Formula (10-3) CH 2 =CR 11 -OR 15 Formula (10-4) CH 2 =CR 11 -R 16 (In the formula, R 11 is defined as above. R 13 represents a hydrogen atom or an alkyl group. R 14 represents an alkyl group. R 15 represents an alkyl group. R 16 represents a nitrile group.)

20. The binder for electrochemical devices according to claim 19, wherein the monomer having a polar group is at least one selected from the group consisting of a non-fluorine-containing monomer having a carboxyl group, a non-fluorine-containing monomer having a sulfo group, and a monomer represented by the following formula (10-1): CH ２ =CR １１ -CO-O-R １３ (10-1) (In the formula, R １１ is a hydrogen atom or an alkyl group, and R １３ is a hydrogen atom or an alkyl group.

21. 21. The binder for electrochemical devices according to claim 19 or 20, which is a binder for lithium ion secondary batteries and is in the form of a sheet.

22. 21. An electrode mixture comprising the tetrafluoroethylene-based polymer composition according to claim 1, 2, 16, or 17, or the binder for electrochemical devices according to claim 5, 6, 19, or 20, and an electrode active material.

23. The electrode mixture according to claim 22, which is in the form of a sheet.

24. 21. An electrode comprising the tetrafluoroethylene-based polymer composition according to claim 1, 2, 16, or 17, or the binder for electrochemical devices according to claim 5, 6, 19, or 20, an electrode active material, and a current collector.

25. A secondary battery comprising the electrode according to claim 24.

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