Chlorosulfonated polyolefin latex

Abstract

Provided is a means for producing a dip-molded article comprising a chlorosulfonated polyolefin without using sodium alginate. More specifically, provided is a chlorosulfonated polyolefin latex containing: (A) a chlorosulfonated polyolefin; (B) a surfactant having an anionic portion and a nonionic portion, the nonionic portion including a polyoxyalkylene chain and the anionic portion including a carboxylate salt, a sulfonate salt, a carbonate salt, a sulfate ester salt, or a phosphate ester salt; (C) at least one surfactant selected from the group consisting of an amino acid-type surfactant, an alkylarylsulfonic acid-type surfactant, an alkylsulfuric acid-type surfactant, and a sulfosuccinic acid-type surfactant; and (D) an aqueous dispersion medium.

Description

Technical Field

[0001] This invention relates to chlorosulfonated polyolefin latexes, and more specifically, to chlorosulfonated polyolefin latexes for dip molding. Furthermore, this invention also relates to dip-molded articles manufactured using the chlorosulfonated polyolefin latex. Background Technology

[0002] Rubber gloves are widely used in various industrial applications, such as household chores, food processing, and electronic component manufacturing, as well as medical applications. A common method for manufacturing rubber gloves is the coagulation-impregnation method using latex. For example, Patent Document 1 discloses a method in which a hand mold corresponding to the three-dimensional shape of a glove is prepared, the surface of the hand mold is treated with a coagulant such as an aqueous solution of calcium nitrate, the treated hand mold is then immersed in an impregnation solution containing nitrile rubber latex, and then lifted out, allowing rubber particles to adhere to the surface of the hand mold. The mixture is then dried and cross-linked to manufacture the glove.

[0003] Chlorosulfonated polyolefins exhibit excellent resistance to strong acids and alkalis, making them a popular raw material for protective gloves used in processes involving highly hazardous chemicals, such as plating, semiconductor manufacturing, and dyeing. Typically, chlorosulfonated polyolefin rubber gloves are manufactured by immersing a glove mold in an organic solvent solution of rubber, followed by drying and vulcanization (e.g., Patent Document 2). However, from an environmental perspective, it is desirable to manufacture gloves using rubber latex, thereby eliminating the need for organic solvents during glove production.

[0004] As a method for manufacturing gloves using chlorosulfonated polyolefin latex, for example, Patent Document 3 discloses the following method: immersing a mold with attached calcium ions into a chlorosulfonated polyethylene latex containing sodium alginate, κ-carrageenan, and pectin to manufacture an impregnated molded body.

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: International Publication No. 2015 / 146974

[0008] Patent Document 2: Japanese Patent Application Publication No. 05-230702

[0009] Patent Document 3: Japanese Patent No. 7033242

[0010] Patent Document 4: International Publication No. 2012 / 141020 Summary of the Invention

[0011] The problem that the invention aims to solve

[0012] However, sodium alginate and the like also have a thickening effect. From the viewpoint of freely controlling viscosity, it is preferable to use latex without sodium alginate or the like to manufacture the impregnated molded article. One aspect of the object of the present invention is to provide a method for manufacturing an impregnated molded article containing chlorosulfonated polyolefin without using sodium alginate or the like, a latex that can be used in the method, and an impregnated molded article containing chlorosulfonated polyolefin that does not require sodium alginate or the like.

[0013] Methods for solving problems

[0014] This invention includes the subject matter described in, for example, the following items.

[0015] <Item 1>

[0016] A chlorosulfonated polyolefin latex, comprising:

[0017] (A) Chlorosulfonated polyolefins;

[0018] (B) A surfactant having an anionic portion and a nonionic portion, wherein the nonionic portion comprises a polyoxyolefin chain and the anionic portion comprises a carboxylate, sulfonate, carbonate, sulfate, or phosphate.

[0019] (C) At least one surfactant selected from the group consisting of amino acid surfactants, alkyl aryl sulfonic acid surfactants, alkyl sulfuric acid surfactants, and sulfosuccinic acid surfactants; and

[0020] (D) Aqueous dispersion medium.

[0021] <Item 2>

[0022] The latex described in item 1 is used for impregnation molding.

[0023] <Item 3-1>

[0024] According to the latex described in item 1 or 2, the content of (C) is 1 to 10 parts by mass relative to 100 parts by mass of (A).

[0025] <Item 3-2>

[0026] According to the latex described in item 1, 2 or 3-1, the content of (B) is 0.3 to 12 parts by mass relative to 100 parts by mass of (A).

[0027] <Item 4-1>

[0028] The latex according to any one of items 1-2, 3-1 and 3-2, wherein,

[0029] Amino acid-type surfactants are at least one amino acid-type surfactant selected from the group consisting of glutamic acid-type surfactants, alanine-type surfactants, sarcosine-type surfactants, glycine-type surfactants, aspartic acid-type surfactants, and taurine-type surfactants.

[0030] Alkyl aryl sulfonic acid surfactants are surfactants in which the alkyl group is a straight-chain or branched C8-C18 alkyl group and the aryl group is a phenylene or naphthylene group.

[0031] Alkyl sulfate surfactants are at least one alkyl sulfate surfactant selected from the group consisting of alkyl sulfate surfactants and polyoxyethylene sulfonic acid surfactants.

[0032] The sulfosuccinic acid type surfactant is at least one sulfosuccinic acid type surfactant selected from the group consisting of monoalkyl sulfosuccinic acid type surfactants, dialkyl sulfosuccinic acid type surfactants, and alkyl alkenyl sulfosuccinic acid type surfactants.

[0033] <Item 4-2>

[0034] According to any one of items 1-2, 3-1 and 3-2, the latex in (C) is a surfactant selected from at least one of the group consisting of alanine-type surfactants, taurine-type surfactants, alkylbenzene sulfonic acid-type surfactants, alkyl sulfate-type surfactants, polyoxyethylene sulfonate-type surfactants, monoalkyl sulfosuccinate-type surfactants, dialkyl sulfosuccinate-type surfactants and alkylalkenyl sulfosuccinate-type surfactants.

[0035] <Item 4-3>

[0036] According to any one of claims 1-2, 3-1 and 3-2, the surfactant of (C) is at least one surfactant selected from the group consisting of N-C8-C18 aliphatic acylmethyl alanine salt and N-C8-C18 aliphatic acylmethyl taurate, straight-chain alkylbenzene sulfonate having a C8-C18 alkyl group, alkyl sulfate and polyoxyethylene sulfonate having a straight-chain or branched C8-C18 alkyl group, and mono-C8-C18 alkyl sulfosuccinate, di-C8-C18 alkyl sulfosuccinate and C8-C18 alkyl C2-C6 alkenyl sulfosuccinate.

[0037] <Item 5>

[0038] The latex according to any one of items 1-2, 3-1-3-2 and 4-1-4-3, wherein the chlorosulfonated polyolefin is chlorosulfonated polyethylene.

[0039] <Item 6-1>

[0040] The latex according to any one of items 1-2, 3-1-3-2, 4-1-4-3 and 5, wherein the surfactant of (B) is a compound represented by formula (I).

[0041] R 1 -O-(CH2CHR 2 -O) n -R 3 (I)

[0042] (where R is in the formula) 1 Indicates that by R 1a - indicates a group or is represented by R 1a -R 1b - indicates a group, R 1a - indicates an alkyl group with 6 to 20 carbon atoms, -R 1b - indicates phenylene, n represents an integer from 2 to 40, R 2 Same or different, indicating hydrogen or methyl, R 3 This can be represented as -SO3M or -COOM, where M indicates an alkali metal.

[0043] <Item 7>

[0044] An impregnation molded body is formed by impregnating the latex described in any one of items 1-2, 3-1-3-2, 4-1-4-3 and 5-6 with a polyvalent metal salt as a coagulant.

[0045] <Item 8>

[0046] The impregnated molded body according to item 7 has a thickness of 0.1 mm or more.

[0047] <Item 9>

[0048] According to item 7, the dip-molded body is a glove.

[0049] <Item 10>

[0050] A method for manufacturing an impregnated molded article, comprising:

[0051] A step of preparing an impregnation composition by mixing (C) at least one surfactant selected from the group consisting of amino acid surfactants, alkyl aryl sulfonic acid surfactants, alkyl sulfuric acid surfactants and sulfosuccinic acid surfactants into a latex, wherein the latex contains (A) chlorosulfonated polyolefin, (B) a surfactant having an anionic and nonionic portion, wherein the nonionic portion comprises a polyoxyethylene chain and the anionic portion comprises a carboxylate, sulfonate, carbonate, sulfate, or phosphate salt, and (D) an aqueous dispersion medium.

[0052] The process of adhering a coagulant to the surface of a mold having a desired shape; and

[0053] The process of immersing a mold coated with a coagulant into an impregnation molding composition to form a solidified film.

[0054] <Item 11>

[0055] The method for manufacturing an impregnated molded article according to item 10 further includes:

[0056] The steps of removing the mold from the dip-molding composition and cleaning the solidified film described above; and

[0057] The process of heating the solidified film.

[0058] Invention Effects

[0059] A method for manufacturing impregnated molded articles containing chlorosulfonated polyolefins without using sodium alginate is provided, along with the latex that can be used in this method and the impregnated molded articles containing chlorosulfonated polyolefins that do not require sodium alginate. This allows for the simple manufacture of impregnated molded articles with preferred strength and excellent chemical resistance. Detailed Implementation

[0060] The various embodiments of the present invention will be described in more detail below. The present invention preferably includes chlorosulfonated polyolefin latex, its uses, and manufacturing methods, but is not limited thereto. The present invention includes all the contents disclosed in this specification and that can be recognized by those skilled in the art.

[0061] The chlorosulfonated polyolefin latex included in this invention comprises: (A) a chlorosulfonated polyolefin; (B) a surfactant having an anionic and nonionic portion, wherein the nonionic portion comprises a polyoxyethylene chain and the anionic portion comprises a carboxylate, sulfonate, carbonate, sulfate, or phosphate salt; (C) at least one surfactant selected from the group consisting of amino acid surfactants, alkyl aryl sulfonic acid surfactants, alkyl sulfate surfactants, and sulfosuccinic acid surfactants; and (D) an aqueous dispersion medium. The chlorosulfonated polyolefin latex included in this invention is sometimes referred to as "the latex of this invention." Additionally, these components are sometimes referred to as components (A) to (D).

[0062] The chlorosulfonated polyolefin, which is component (A), is obtained by chlorinating and chlorosulfonating a polyolefin. Examples of polyolefins include polymers or copolymers of α-olefins, copolymers of α-olefins with other polymerizable components, etc.

[0063] Examples of α-olefins include ethylene, propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene, 1-octene, and 1-decene. Other polymerizable components include chain dienes such as isoprene, 1,3-butadiene, 1,4-hexadiene, 1,6-octadiene, and 2-methyl-1,5-hexadiene; cyclic dienes such as 1,4-cyclohexadiene, dicyclopentadiene, 5-vinyl-2-norbornene, 5-ethylidene-2-norbornene, 5-methylene-2-norbornene, 5-isopropylidene-2-norbornene, and 6-chloromethyl-5-isopropenyl-2-norbornene; and vinyl compounds such as vinyl acetate, vinyl chloride, acrylonitrile, styrene, methyl acrylate, and methyl methacrylate.

[0064] As a chlorosulfonated polyolefin, a chlorosulfonated α-olefin polymer is preferred. In a chlorosulfonated α-olefin polymer, one or more α-olefins may be used alone. When two or more α-olefins are used, ethylene is preferred as one of them.

[0065] More specifically, examples of chlorosulfonated polyolefins include chlorosulfonated polyethylene, chlorosulfonated ethylene-α-olefin copolymers, and chlorosulfonated α-olefin polymers. It should be noted that "α-olefin" in chlorosulfonated ethylene-α-olefin copolymers and chlorosulfonated α-olefin polymers refers to α-olefins other than ethylene. Propylene is a preferred example of an α-olefin other than ethylene. That is, chlorosulfonated ethylene-α-olefin copolymers are preferably exemplified by chlorosulfonated ethylene-propylene copolymers, and chlorosulfonated propylene polymers are preferably exemplified by chlorosulfonated α-olefin polymers.

[0066] Chlorosulfonated polyolefins can be used alone or in combination with two or more.

[0067] Furthermore, the sulfur content in the chlorosulfonated polyolefin is preferably 0.5% by mass or more, more preferably 0.8% by mass or more. It is also preferably 2.0% by mass or less, more preferably 1.5% by mass or less. Additionally, it is preferably 0.5 to 2.0% by mass, more preferably 0.8 to 1.5% by mass.

[0068] The chlorine content in the chlorosulfonated polyolefin of the present invention is not particularly limited, but is preferably 10% by mass or more, more preferably 20% by mass or more. Furthermore, it is preferably 50% by mass or less, more preferably 40% by mass or less. Additionally, it is preferably 10 to 50% by mass, more preferably 20 to 40% by mass.

[0069] The sulfur and chlorine content of chlorosulfonated polyolefins are the contents of sulfur and chlorine atoms in the chlorosulfonated polyolefins, respectively, and can be determined by the oxygen flask combustion method.

[0070] Methods for chlorinating and chlorosulfonating polyolefins include solution methods where the polyolefin is dissolved in an organic solvent and the reaction is carried out in a homogeneous system; suspension methods where the polyolefin is suspended in a solvent and the reaction is carried out; melt methods where the reaction is carried out in a molten state; and gas-phase methods where the polyolefin is suspended in a gas phase and the reaction is carried out. From the viewpoint of uniformly carrying out chlorination and chlorosulfonation, solution methods are preferred. Examples of chlorinating and chlorosulfonating agents used include the combined use of chlorine and sulfur dioxide, the combined use of chlorine and sulfonyl chloride, and the use of sulfonyl chloride alone. The chlorosulfonation reaction can be carried out by using a chlorinating agent, a chlorosulfonating agent, a free radical generator, and a co-catalyst such as pyridine, as needed.

[0071] Commercially available chlorosulfonated polyolefins can be used. Examples of commercially available products include Tosoh Corporation's trade names "TOSO-CSM" and "extos" (chlorosulfonated polyethylene).

[0072] The content of (A) in the latex of the present invention is preferably about 20% to about 60% by mass, more preferably about 25% to about 55% by mass, and even more preferably about 30% to about 50% by mass.

[0073] (B) The surfactant is a surfactant having an anionic and nonionic portion, wherein the nonionic portion comprises a polyoxyolefin chain, and the anionic portion comprises a carboxylate, sulfonate, carbonate, sulfate, or phosphate (preferably a carbonate or sulfate). It should be noted that alkali metal salts (especially sodium and potassium salts), ammonium salts, amine salts, etc., can be listed as such salts, with alkali metal salts being preferred.

[0074] Polyoxyethylene, polyoxypropylene, or polyoxyethylene-polyoxypropylene are preferred examples of this polyoxyethylene, with polyoxyethylene being particularly preferred. Furthermore, the number of moles of the olefin added (repetition number) is preferably an integer from 2 to 40 (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, or 40).

[0075] As component (B), a surfactant having a polyoxyalkylene ether structure or a polyoxyalkylene phenyl ether structure is more preferred.

[0076] As for the "alkyl ether" in the polyoxyethylene alkyl ether structure, alkyl ethers with 6 to 20 carbon atoms (6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20) are preferably listed. Furthermore, as for the "alkyl phenyl ether" in the polyoxyethylene alkyl phenyl ether structure, alkyl phenyl ethers in which a phenylene (especially 1,4-phenylene) exists between the alkyl and oxygen atoms are preferred.

[0077] As component (B), more specifically, the compound shown in formula (I) is particularly preferred.

[0078] R 1 -O-(CH2CHR 2 -O) n -R 3 (I)

[0079] In equation (I), R 1 Indicates that by R 1a - indicates a group or is represented by R 1a -R 1b - indicates a group. R 1a - indicates an alkyl group with 6 to 20 carbon atoms (6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20). Additionally, -R 1b - indicates phenylene (preferably 1,4-phenylene).

[0080] R 2 This represents a hydrogen atom or a methyl group. n is the number of moles of olefin added, which is an integer from 2 to 40, preferably an integer from 2 to 35, and more preferably an integer from 2 to 20.

[0081] R 3 It can be represented as -SO3M or -COOM. Additionally, M represents an alkali metal, preferably sodium (Na) or potassium (K).

[0082] In formula (I), (CH2CHR) 2 -O)n represents a polyoxyethylene unit that can contain R 2 Two different polyoxyethylenes, namely polyoxyethylene ((CH2CH2-O)x) and polyoxypropylene ((CH2CH(CH3)-O)y) in a manner where the sum of x and y is n.

[0083] In equation (I), R 1 Indicates that by R 1a - indicates a group and R 3In the case of -SO3M, formula (I) represents polyoxyethylene alkyl ether sulfate. Specific examples of this polyoxyethylene alkyl ether sulfate include: sodium polyoxyethylene lauryl ether sulfate, sodium polyoxyethylene tridecyl ether sulfate, sodium polyoxyethylene myristyl ether sulfate, sodium polyoxyethylene oleyl ether sulfate, etc.; sodium polyoxypropylene lauryl ether sulfate, sodium polyoxypropylene tridecyl ether sulfate, sodium polyoxypropylene myristyl ether sulfate, and sodium polyoxypropylene oleyl ether sulfate, etc.; and sodium polyoxyethylene polyoxypropylene lauryl ether sulfate and sodium polyoxyethylene polyoxypropylene tridecyl ether sulfate, etc. Preferably, sodium polyoxyethylene lauryl ether sulfate, sodium polyoxyethylene tridecyl ether sulfate, sodium polyoxyethylene myristyl ether sulfate, sodium polyoxypropylene lauryl ether sulfate, sodium polyoxypropylene tridecyl ether sulfate, sodium polyoxyethylene polyoxypropylene lauryl ether sulfate, and sodium polyoxyethylene polyoxypropylene tridecyl ether sulfate are also mentioned. They can be used individually or in combination of two or more.

[0084] The polyoxyalkylene ether sulfate shown in Formula (I) can be used alone or in combination with two or more. When using one polyoxyalkylene ether sulfate, it is particularly preferred to use a polyoxyalkylene ether sulfate in Formula (I) where n is an integer from 2 to 20. On the other hand, when using two or more polyoxyalkylene ether sulfates, it is preferred to use a polyoxyalkylene ether sulfate containing a polyoxyalkylene ether sulfate (IA) in Formula (I) where n is an integer from 9 to 35 and a polyoxyalkylene ether sulfate (IB) in Formula (I) where n is an integer from 2 to 8. It should be noted that the polyoxyalkylene ether sulfate (IA) and the polyoxyalkylene ether sulfate (IB) are preferably selected such that the difference between n in Formula (I) is 8 to 30, and more preferably such that the difference between n in Formula (I) is 10 to 20.

[0085] When polyoxyalkylene ether sulfate (IA) and polyoxyalkylene ether sulfate (IB) are used together, the polyoxyalkylene ether sulfate preferably contains 0.1 to 5 parts by mass of polyoxyalkylene ether sulfate (IB) relative to 1 part by mass of polyoxyalkylene ether sulfate (IA), and more preferably contains 0.3 to 3 parts by mass of polyoxyalkylene ether sulfate (IB).

[0086] In the latex of the present invention, the content of component (B) is preferably set to 0.3 to 12 parts by mass relative to 100 parts by mass of chlorosulfonated polyolefin (A). When the amount of component (B) used is less than 0.3 parts by mass, the static stability and mechanical stability of the resulting latex may decrease. The above-mentioned part by mass range (0.3 to 12 parts by mass) is more preferably 0.5 to 10 parts by mass, and even more preferably 1 to 5 parts by mass.

[0087] As described above, the surfactant in component (C) is at least one surfactant selected from the group consisting of amino acid surfactants, alkyl aryl sulfonic acid surfactants, alkyl sulfuric acid surfactants, and sulfosuccinic acid surfactants.

[0088] As an amino acid-type surfactant, compounds having a structure formed by amide bonding of a fatty acid and an amino acid salt are preferred. As the fatty acid, coconut oil fatty acids and C8-C18 (C8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18) straight-chain or branched fatty acids are preferred. Furthermore, as the amino acid, glutamic acid, aspartic acid, glycine, alanine, methylalanine, sarcosine, methyltaurine, etc., are preferred. It should be noted that as the salt, alkali metal salts are preferred, sodium or potassium salts are more preferred, and sodium salts are even more preferred.

[0089] More specifically, amino acid-type surfactants include glutamate-type surfactants such as N-coconut oil fatty acid glutamate, N-lauroyl glutamate, and N-myristoyl glutamate; alanine-type surfactants such as N-coconut oil fatty acid alanine, N-lauroyl alanine, N-coconut oil fatty acid methyl alanine, and N-lauroyl methyl alanine; sarcosine-type surfactants such as N-coconut oil fatty acid sarcosine and N-lauroyl sarcosine; glycine-type surfactants such as N-coconut oil fatty acid glycine and N-lauroyl glycine; aspartic acid-type surfactants such as N-coconut oil fatty acid aspartate, N-lauroyl aspartate, and N-myristoyl aspartate; and taurine-type surfactants such as N-coconut oil fatty acid methyl taurine, N-lauroyl methyl taurine, N-myristoyl methyl taurine, and N-stearoyl methyl taurine. It should be noted that, as a salt, an alkali metal salt is preferred, a sodium or potassium salt is more preferred, and a sodium salt is even more preferred. From the viewpoint of coagulation efficiency, it is preferably selected from at least one of the group consisting of alanine-type surfactants and taurine-type surfactants, and particularly preferably from at least one of the group consisting of sodium N-C8 to C18 aliphatic acylmethyl alanine and sodium N-C8 to C18 aliphatic acylmethyl taurate.

[0090] As alkylaryl sulfonic acid surfactants, alkylaryl sulfonic acid surfactants having a straight-chain or branched (preferably straight-chain) alkyl group of C8 to C18 (C8, 9, 10, 11, 12, 13, 14, 15, 16, 17, or 18) alkyl group are preferred. Furthermore, benzene or naphthalene is preferred as the aryl group (i.e., phenylene or naphthylene is preferred; 1,4-phenylene is more preferred as phenylene; and 1,4-naphthylene is more preferred as naphthylene). More specifically, examples include straight-chain or branched alkylbenzene sulfonic acid surfactants such as octylbenzene sulfonate, decylbenzene sulfonate, undecylbenzene sulfonate, dodecylbenzene sulfonate, and tetradecylbenzene sulfonate; and straight-chain or branched alkylnaphthalene sulfonic acid surfactants such as butylnaphthalene sulfonate, octylnaphthalene sulfonate, decylnaphthalene sulfonate, and dodecylnaphthalene sulfonate. It should be noted that alkali metal salts are preferred as salts, sodium or potassium salts are more preferred, and sodium salts are even more preferred. From the viewpoint of solidification efficiency, linear alkylbenzene sulfonates having C8 to C18 alkyl groups are preferred, and linear alkylbenzene sulfonates having C10 to C16 alkyl groups are particularly preferred.

[0091] As an alkyl sulfate type surfactant, it can be an alkyl sulfate type surfactant, preferably an alkyl sulfate having a straight-chain or branched alkyl group of C8 to C18 (C8, 9, 10, 11, 12, 13, 14, 15, 16, 17 or 18), and more preferably an alkyl sulfate having a straight-chain alkyl group. More specifically, examples include straight-chain alkyl sulfate type surfactants such as octyl sulfate, decyl sulfate, undecyl sulfate, dodecyl sulfate (lauryl sulfate), α-olefin (C12 to 14) sulfate, α-olefin (C14 to 16) sulfate, stearyl sulfate, etc.; and branched-chain alkyl sulfate type surfactants such as 2-ethylhexyl sulfate, isostearyl sulfate, etc. It should be noted that as a salt, an alkali metal salt is preferred, more preferably a sodium or potassium salt, and even more preferably a sodium salt. Among these, from the viewpoint of coagulation efficiency, straight-chain alkyl sulfates of C8 to C18 are preferred, and straight-chain alkyl sulfates of C10 to C14 are particularly preferred.

[0092] As an alkyl sulfate type surfactant, a portion of the methylene group in its alkyl chain can be replaced by an ether bond (-O-), for example, alkyl sulfate type surfactants in which the alkyl chain is changed to a polyoxyethylene chain are also included. As an alkyl sulfate type surfactant, polyoxyethylene sulfonate type surfactants are also included, which can be polyoxyethylene sulfonate type surfactants, wherein polyoxyethylene sulfonates (especially polyoxyethylene monosulfonates and polyoxyethylene disulfonates) are preferred.

[0093] As a sulfosuccinic acid type surfactant, it can be a monoalkyl sulfosuccinic acid type surfactant, a dialkyl sulfosuccinic acid type surfactant, or an alkylalkenyl sulfosuccinic acid type surfactant. Examples include monoalkyl sulfosuccinic acid type surfactants such as monolauryl sulfosuccinate and monococoate fatty acid sulfosuccinate; dialkyl sulfosuccinic acid type surfactants such as diisobutyl sulfosuccinate, dihexyl sulfosuccinate, dioctyl sulfosuccinate, di(2-ethylhexyl)sulfosuccinate, and dinonyl sulfosuccinate; and alkylalkenyl sulfosuccinic acid type surfactants such as octylallyl sulfosuccinate, 2-ethylhexylallyl sulfosuccinate, nonylallyl sulfosuccinate, and dodecylallyl sulfosuccinate. It should be noted that, as a salt, an alkali metal salt is preferred, a sodium or potassium salt is more preferred, and a sodium salt is even more preferred. From the viewpoint of solidification efficiency, at least one of the following is particularly preferred: mono-C8-C18 alkyl sulfonyl succinate, di-C8-C18 alkyl sulfonyl succinate, and C8-C18 alkyl-C2-C6 alkenyl sulfonyl succinate.

[0094] The surfactant in component (C) can be synthesized appropriately or a commercially available product can be used. Furthermore, as mentioned above, the surfactant in component (C) can be used alone or in combination of two or more.

[0095] As component (C), it is more preferably selected from at least one of the group consisting of taurine-type surfactants, alkylbenzene sulfonic acid-type surfactants and dialkyl sulfosuccinic acid-type surfactants.

[0096] It should be noted that, without impairing the inventive effect of this invention, the latex of this invention may also contain surfactants other than components (B) and (C). Examples of such surfactants include alkyl sulfonate surfactants such as nonane sulfonate and dodecane sulfonate; fatty acid surfactants such as oleate, stearate, and myristate; alkylene disulfonate surfactants such as polyoxypropylene disulfonate and polyoxypropylene disulfonate; rosin-type surfactants such as rosin salts, hydrogenated rosin salts, and disproportionated rosin salts; and sulfated oil-type surfactants such as sulfated castor oil, sulfated tallow, and sulfated rapeseed oil.

[0097] In the latex of the present invention, the content of component (C) is preferably 0.5 to 12 parts by mass relative to 100 parts by mass of component (A). The upper or lower limit of this range can be, for example, 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, 10, 10.5, 11, or 11.5. More preferably, this range is 1 to 10 parts by mass, and even more preferably 2 to 8 parts by mass.

[0098] Water is preferably used as the aqueous dispersion medium for component (D). It should be noted that the content of component (D) in the latex of the present invention can be appropriately set according to the degree of emulsification, viscosity, etc. of the latex. For example, in the latex of the present invention, it is preferable to contain 60% by mass or more, more preferably 65% ​​by mass or more, or 70% by mass or more. It can also be used as the balance of components other than component (D), adjusting the content ratio of each component while ensuring the overall latex content is 100% by mass.

[0099] As described above, the latex of the present invention is suitable for preparing impregnated molded articles containing chlorosulfonated polyolefins even without containing sodium alginate or the like. However, it is not excluded to further incorporate sodium alginate or the like into the components (A) to (D) above. In other words, the latex of the present invention preferably contains a latex that does not contain sodium alginate or the like. More specifically, the latex of the present invention preferably does not contain alginic acid or its salts (especially sodium salts), carrageenan (especially κ-carrageenan), or pectin.

[0100] As a method for manufacturing the latex according to the present invention, one example is a method in which component (C) is added to a latex containing components (A), (B), and (D) after the latex has been prepared. For convenience, the latex containing components (A), (B), and (D) before the addition of component (C) is sometimes referred to as the precursor latex.

[0101] Methods for manufacturing precursor latex include melting component (A) and dispersing it in an aqueous dispersion medium containing component (B); dissolving component (A) in an organic solvent and dispersing it in an aqueous dispersion medium containing component (B), followed by removing the organic solvent. The removed organic solvent can be easily recycled and reused. Component (B) can function as an emulsifier. From the viewpoint of easily controlling the particle size of component (A) in the resulting latex, the latter method is preferred.

[0102] Examples of methods for dispersing component (A) in an aqueous dispersion medium using an organic solvent include: phase inversion emulsification, which involves adding an aqueous dispersion medium to component (A) dissolved in an organic solvent to form a water-in-oil (W / O) emulsion, followed by phase inversion to an oil-in-water (O / W) emulsion upon the addition of water; and forced emulsification, which uses an emulsification device to mechanically disperse component (A) dissolved in an organic solvent in water in the presence of component (B). These methods can be used individually or in combination.

[0103] As for the aforementioned organic solvents, there are no particular limitations on any organic solvent that can dissolve component (A) and is immiscible with water. Examples include aliphatic hydrocarbon solvents such as hexane, heptane, and cyclohexane; aromatic hydrocarbon solvents such as benzene, toluene, and xylene; chlorinated hydrocarbon solvents such as chloroform and 1,2-dichloroethane; alcohol solvents such as 1-butanol and isobutanol; ester solvents such as ethyl acetate, isopropyl acetate, and n-butyl acetate; ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone; and ether solvents such as diisopropyl ether, dibutyl ether, and anisole. These organic solvents can be used individually or in combination of two or more.

[0104] The amount of organic solvent used here is not particularly limited, but it is preferred to set the concentration of component (A) in the composition formed by dissolving component (A) in the organic solvent to be 5 to 25% by mass, and more preferably to set the concentration of component (A) to be 8 to 20% by mass.

[0105] Furthermore, the amount of component (B) used is not particularly limited, but is preferably 0.3 to 12 parts by mass relative to 100 parts by mass of component (A), more preferably 0.5 to 10 parts by mass, and particularly preferably 1 to 5 parts by mass.

[0106] As the emulsification device, known emulsification devices can be used, such as paddle mixers, planetary mixers, homogenizers, homogenizers, dispersion mixers, etc. The emulsification device can be batch or continuous.

[0107] The temperature during emulsification also depends on the type of organic solvent used, so it cannot be generalized. It is usually about 5°C to about 70°C.

[0108] To remove organic solvents from the emulsion obtained by the above method, distillation can be performed, for example, under normal pressure, reduced pressure, or pressurized pressure. In this case, the concentration of component (A) in the latex can also be adjusted to remove water simultaneously as needed. During this organic solvent removal operation, an antifoaming agent can be used to suppress foaming caused by the emulsifier. Examples of antifoaming agents include mineral oil-based antifoaming agents, polysiloxane-based antifoaming agents, acetylene-based antifoaming agents, metal soap-based antifoaming agents, acrylic antifoaming agents, and fluorinated antifoaming agents. Acetylene-based antifoaming agents are preferred. They can be used alone or in combination of two or more. The amount of antifoaming agent used also depends on the amount of component (B) used, and is preferably 100–2000 ppmwt (100 × 10⁻⁶) relative to 100 parts by mass of component (A). -6 ~2000×10 -6(Parts by weight). The defoamer can be added to the emulsion before the removal operation, or it can be added appropriately during the removal operation. Methods of addition include one-time addition, dripping, spraying, etc. When removing water after removing the organic solvent to further adjust the concentration, it can be removed by distillation, centrifugation, membrane separation, filtration, etc.

[0109] Commercially available precursor latex can be used. Examples of commercially available products include Sumitomo Seika Co., Ltd.'s product name "Ceporex CSM-N".

[0110] The latex of the present invention can be prepared, for example, by adding component (C) to the precursor latex.

[0111] The amount of component (C) added is preferably 0.5 to 12 parts by mass, more preferably 1 to 10 parts by mass, and more preferably 2 to 8 parts by mass, relative to 100 parts by mass of component (A) in the precursor latex.

[0112] Without impairing the inventive effect of the present invention, the latex of the present invention may also contain known additives such as rheology modifiers, anti-aging agents, defoamers, pH adjusters, chelating agents, vulcanizing agents, vulcanization accelerators, vulcanization accelerator aids, acid acceptors, film-forming aids, plasticizers, fillers, pigments, and thickeners.

[0113] As rheology modifiers, examples include polysaccharides such as cellulose, cellulose nanofibers, cellulose nanocrystals, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, carboxymethyl cellulose, chitin, chitosan, guar gum, xanthan gum, polyacrylic acid, sodium polyacrylate, cross-linked polyacrylic acid, polyacrylamide, polyvinyl alcohol, polyvinyl methyl ether, polyvinylpyrrolidone, and other water-soluble vinyl polymers, as well as clay minerals such as montmorillonite, chlorodeionite, soapstone, bedeite, and hydropyrite.

[0114] Examples of anti-aging agents include phenolic anti-aging agents such as butylated hydroxytoluene, 2,2'-methylenebis(4-ethyl-6-tert-butylphenol), and 2,5-di-tert-butylhydroquinone; amine anti-aging agents such as N-phenyl-1-naphthylamine and di(4-octylphenyl)amine; phosphorus anti-aging agents such as tri(nonylphenyl) phosphite; sulfur anti-aging agents such as dilauryl thiodipropionate, 2-mercaptobenzimidazole, and nickel dibutyldithiocarbamate; and bisphenol A type epoxy resins.

[0115] As defoamers, examples include oil-based defoamers, mineral oil-based defoamers, polysiloxane-based defoamers, and polyether-based defoamers.

[0116] Examples of pH adjusters include sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, ammonia, trimethylamine, triethanolamine, hydrochloric acid, sulfuric acid, phosphoric acid, citric acid, and acetic acid.

[0117] Examples of chelating agents include ethylenediaminetetraacetic acid, hypozinotriacetic acid, trans-1,2-cyclohexanediaminetetraacetic acid, diethylenetriaminepentaacetic acid, bis(aminoethyl) glycol ether-N,N,N',N'-tetraacetic acid, N-(2-hydroxyethyl)ethylenediamine-N,N',N'-triacetic acid, dihydroxyethylglycine, 1-hydroxyethane-1,1-diphosphonic acid, gluconic acid, citric acid, malic acid, and tartaric acid.

[0118] As vulcanizing agents, examples include powdered sulfur, sulfur bloom, precipitated sulfur, colloidal sulfur, and other sulfur compounds; organic peroxides such as di-tert-butyl peroxide and dicumyl peroxide; maleimide compounds such as N,N'-m-phenylene bismaleimide; quinone compounds such as p-quinone dioxime and p,p'-dibenzoylquinone dioxime; metal compounds such as magnesium oxide and lead oxide; and polyol compounds such as pentaerythritol, dipentaerythritol, sorbitol, and trimethylolpropane.

[0119] Examples of vulcanization accelerators include diethyldithiocarbamate, dibutyldithiocarbamate, diphenyldithiocarbamate, sodium diethyldithiocarbamate, sodium dibutyldithiocarbamate, sodium diphenyldithiocarbamate, zinc diethyldithiocarbamate, zinc dibutyldithiocarbamate, zinc diphenyldithiocarbamate, 2-mercaptobenzothiazole, zinc 2-mercaptobenzothiazole, and dibenzothiazole disulfide. 2-(4'-morpholinodithio)benzothiazole, trimethylthiourea, N,N'-diethylthiourea, 1,3-diphenylguanidine, 1,3-di-o-tolylguanidine, N-cyclohexyl-2-benzothiazole sulfenamide, N-oxodiethylene-2-benzothiazole sulfenamide, tetramethylthiuram disulfide, tetraethylthiuram disulfide, tetramethylthiuram monosulfide, dipentamethylenethiuram tetrasulfide, zinc isopropyl xanthionate, etc.

[0120] Examples of accelerators for vulcanization include metal oxides such as zinc oxide and magnesium oxide; and fatty acids such as stearic acid and palmitic acid.

[0121] Examples of acid acceptors include metal oxides such as lead oxide, magnesium oxide, zinc oxide, and calcium oxide; metal hydroxides such as magnesium hydroxide, calcium hydroxide, and aluminum hydroxide; clay minerals such as hydrotalcite; and epoxy compounds such as phenyl glycidyl ether, bisphenol A diglycidyl ether, epoxidized soybean oil, epoxidized linseed oil, epoxidized polybutadiene, and polyglycidyl methacrylate.

[0122] Examples of film-forming aids include propylene glycol, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, ethylene glycol mono-n-butyl ether, ethylene glycol monoisobutyl ether, ethylene glycol mono-tert-butyl ether, ethylene glycol monophenyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monoisopropyl ether, diethylene glycol mono-n-butyl ether, diethylene glycol monoisobutyl ether, diethylene glycol mono-tert-butyl ether, diethylene glycol monophenyl ether, diethylene glycol dimethyl ether, diethylene glycol dimethyl ether, diethylene glycol methyl ethyl ether, triethylene glycol monobutyl ether, triethylene glycol dimethyl ether, tetraethylene glycol dimethyl ether, dipropylene glycol mono-n-butyl ether, dipropylene glycol dimethyl ether, tripropylene glycol monomethyl ether, and 2,2,4-trimethyl-1,3-pentanediol monoisobutyrate, etc.

[0123] Examples of plasticizers include phthalates, adipates, glyceryl fatty acid esters, polyether polyols, and polyester polyols.

[0124] Examples of fillers include carbon fiber, cellulose fiber, carbon black, silica, talc, clay, calcium carbonate, titanium dioxide, and barium sulfate.

[0125] As pigments, examples include carbon black, titanium dioxide, chromium oxide, Prussian blue, amber, nickel titanium yellow, chrome green, cobalt blue, phthalocyanine blue, phthalocyanine green, molybdenum orange, chrome yellow, anthraquinone, and quinacridone.

[0126] When additives are present, the amount of additives contained in the latex of the present invention is not particularly limited, but is preferably 5 to 30 parts by mass relative to 100 parts by mass of the solid component (i.e., component (A)) in the latex composition.

[0127] The preparation method of the latex of the present invention is not particularly limited, and examples include: a method of mixing component (C) and various other additives as needed in a precursor latex using a disperser such as a ball mill, bead mill, kneader, or disperser; a method of preparing an aqueous dispersion containing component (C) and various other additives as needed using a disperser in advance, and then mixing the aqueous dispersion with the precursor latex; a method of mixing component (C) and a portion of the additives in a precursor latex, and then mixing an aqueous dispersion of the additives with other additives; and a method of mixing a portion of the additives in a precursor latex, and then mixing it with an aqueous dispersion of component (C) and other additives, etc.

[0128] From the viewpoint of easy coagulation, the pH of the latex of the present invention is preferably pH 5 or higher, and more preferably pH 7 to 12.

[0129] The solid content of the latex of the present invention is preferably 20-60% by mass, more preferably 25-50% by mass.

[0130] The viscosity of the latex of the present invention is preferably 20–300 mPa·s at 25°C, more preferably 30–200 mPa·s, and particularly preferably 50–100 mPa·s. When the viscosity is within this range, it is easy to obtain a film with uniform thickness during impregnation molding. It should be noted that the viscosity in the present invention is the viscosity measured one minute after measurement using a Brookfield viscometer with rotor No. 1 or No. 2 at a rotation speed of 60 rpm.

[0131] The latex of the present invention is preferably used for dip molding. In other words, the latex of the present invention is preferably used as a composition for dip molding.

[0132] The latex of the present invention can be cured (also known as pre-vulcanization) before being supplied for impregnation molding. The curing time can be appropriately set according to the type of additives and the curing temperature, for example, preferably 1 to 7 days, more preferably 1 to 3 days. In addition, the curing temperature is preferably 10 to 50°C, more preferably 20 to 40°C.

[0133] After curing, it is preferably stored at a temperature below 30°C before being used for impregnation molding.

[0134] The particle size of component (A) in the latex of the present invention is not particularly limited, but the median particle size on a volume basis, as measured by a laser diffraction particle size analyzer, is preferably 0.1–10 μm, more preferably 0.3–5 μm, and particularly preferably 0.5–2.0 μm. When the particle size is within this range, a dense film is more easily obtained during coagulation. This particle size can be adjusted, for example, by the organic solvent used in the preparation of the precursor latex, the type and amount of emulsifier, the amount of water used, and the operating conditions of the emulsification apparatus. Alternatively, it can be adjusted by the amount of component (C) used in preparing the latex of the present invention from the precursor latex, the type and amount of known additives that can be used as needed, and the preparation method.

[0135] To improve the stability of the latex of the present invention, dispersing stabilizers such as polyvinyl alcohol, polyvinylpyrrolidone, and hydroxyethyl cellulose, and additives such as butylated hydroxytoluene, 2,5-di-tert-butylhydroquinone, and bisphenol A type epoxy resin can be added. Such additives can be added to the precursor latex, or, depending on the type of additive, to the organic solvent solution or water used during emulsification during the preparation of the precursor latex. Alternatively, they can be added beforehand to component (A) as a raw material. It should be noted that the additive is generally preferably added in the form of an aqueous solution or aqueous dispersion, either alone or in mixtures. When this additive is added, the total amount is preferably 0.1 to 10 parts by weight relative to 100 parts by weight of component (A).

[0136] The present invention also includes dip-molded articles obtained by using the latex of the present invention as a dip-molding composition.

[0137] Dip molding is a method in which a mold (molding mold) is immersed in a dip molding composition, causing the composition to deposit on the surface of the mold, the mold is then lifted from the composition, and the composition deposited on the surface of the mold is dried. The method for preparing dip-molded articles of the present invention is described in more detail below.

[0138] The mold used in dip molding can be made of ceramic, metal, glass, plastic, or other materials, and corresponds to the desired three-dimensional shape. The surface of the mold can be finished to resemble a pear skin, or made of other raw materials such as fibers or other types of rubber films, depending on the purpose of the dip-molded body. Furthermore, the mold can be preheated before being dipped into the dip molding composition.

[0139] Before immersing the mold in the dip-molding composition, or after removing the mold from the dip-molding composition, a coagulant is preferably used to coagulate the solid component (sometimes called the rubber component) with chlorosulfonated polyolefin as the main component. Methods of using the coagulant include: immersing the mold before immersion in the dip-molding composition into a solution of the coagulant (hereinafter also referred to as the coagulant liquid) to allow the coagulant to adhere to the mold; and immersing the mold with the dip-molding composition deposited on it into the coagulant liquid. From the viewpoint of obtaining a dip-molded body with less thickness unevenness, the method of immersing the mold before immersion in the dip-molding composition into a solution of the coagulant to allow the coagulant to adhere to the mold is preferred.

[0140] Metal salts can be used as coagulants, with water-soluble metal salts being more preferred. Among metal salts, from the viewpoint of high coagulation power, polyvalent metal salts that generate polyvalent metal ions are preferred, and water-soluble polyvalent metal salts are even more preferred. Examples of water-soluble metal salts include metal halides such as sodium chloride, potassium chloride, barium chloride, calcium chloride, magnesium chloride, zinc chloride, and aluminum chloride; metal nitrates such as sodium nitrate, potassium nitrate, barium nitrate, calcium nitrate, zinc nitrate, and aluminum nitrate; metal acetates such as sodium acetate, potassium acetate, barium acetate, calcium acetate, zinc acetate, and aluminum acetate; and water-soluble metal sulfates such as sodium sulfate, potassium sulfate, calcium sulfate, magnesium sulfate, and aluminum sulfate. Alkaline earth metals are preferred as polyvalent metals, with calcium, barium, and magnesium being more preferred, and calcium being the most preferred. Furthermore, from the viewpoint of high solubility in water, calcium chloride and calcium nitrate are particularly preferred as coagulants. These coagulants can be used alone or in combination of two or more.

[0141] The coagulant is preferably used in the form of an aqueous solution. This aqueous solution may also contain water-soluble organic solvents such as methanol and ethanol, and nonionic surfactants. The concentration of the coagulant is not particularly limited, but is preferably 5-50% by mass, more preferably 10-40% by mass, and particularly preferably 15-35% by mass. The immersion time of the molding die in the coagulant is not particularly limited, but is generally preferably 5-300 seconds, more preferably 10-100 seconds.

[0142] After immersing the molding die in the coagulating liquid to allow the liquid to adhere to its surface, the solvent in the coagulating liquid can be removed by drying. The drying temperature can be appropriately set depending on the type of solvent and salt used, preferably 60–150°C, more preferably 80–120°C. Furthermore, the drying time is not particularly limited, preferably 1–600 seconds, more preferably 5–300 seconds. By drying the coagulating liquid on the surface of the molding die, it is easy to form a state where salt is uniformly adhered to the surface of the molding die.

[0143] The time for immersing the molding die in the latex (implant molding composition) of the present invention can be appropriately set according to the desired thickness (film thickness), preferably 5 to 600 seconds, more preferably 10 to 300 seconds.

[0144] After the molding die is lifted from the dip-molding composition, it is usually heated to dry the solidified film formed on the die surface. The drying method is not particularly limited; hot air heating devices, infrared heating devices, microwave heating devices, high-frequency heating devices, etc., can be used. The drying temperature is not particularly limited, but is preferably 50–160°C, more preferably 60–140°C, and particularly preferably 70–120°C. Furthermore, the drying time is not particularly limited, but is preferably 1–120 minutes, more preferably 10–100 minutes, and particularly preferably 20–60 minutes.

[0145] Alternatively, further heating can be applied as needed to vulcanize the solidified film formed on the mold surface. The heating conditions during vulcanization are not particularly limited, but 60–200°C is preferred, more preferably 80–180°C, and particularly preferably 100–160°C. By maintaining the heating temperature within this range, a suitable vulcanization rate can be achieved while suppressing the deterioration of the rubber components caused by excessive heating. The heating time for vulcanization can be appropriately selected based on the heating temperature, typically ranging from 5 to 120 minutes. The heating method can, for example, be the same as the heating method described above.

[0146] In addition, before or after heating the mold on which the impregnation molding composition has been deposited, it is preferable to clean the mold with water or warm water to remove water-soluble impurities (e.g., residual emulsifier, surfactant, coagulant, uncured latex, etc.). The temperature of the water or warm water used is preferably 20 to 80°C, more preferably 30 to 70°C. The cleaning time is preferably about 0.5 minutes to about 60 minutes.

[0147] After drying (and further vulcanization as needed), the dipped molded body is removed from the molding die. Methods of removal include peeling by hand, peeling using a peeling roller, and peeling using water pressure or compressed air pressure. After removal from the die, the dipped molded body can be further washed. Furthermore, as needed, to prevent adhesion between the contact surfaces of the dipped molded bodies and improve smoothness during loading and unloading, inorganic microparticles such as talc or calcium carbonate, or organic microparticles such as corn starch, can be coated on the surface; or an elastomer layer containing microparticles can be further formed on the surface; or the surface layer can be chlorinated.

[0148] The resulting impregnated molded body has a film thickness preferably of 0.1 to 2 mm, more preferably 0.2 to 1.5 mm, and particularly preferably 0.3 to 1.0 mm. As described above, the film thickness can be appropriately set according to the impregnation time, etc.

[0149] It should be noted that, in this specification, "comprising" also includes "consisting essentially of" and "consisting of." Furthermore, this invention encompasses all arbitrary combinations of the technical features described in this specification.

[0150] Furthermore, the various characteristics (properties, structures, functions, etc.) described in the above embodiments of the present invention can be arbitrarily combined when determining the subject matter encompassed by the present invention. That is, the present invention includes all combinations of the various characteristics that can be combined as described in this specification.

[0151] Example

[0152] The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited by these examples or any other examples.

[0153] The surfactants used in the following examples and comparative examples are listed below.

[0154] A: Sodium alkyl (C10-16)benzenesulfonate (manufactured by Nippon Oil Co., Ltd., trade name "Newrex R", solid content concentration 50% by mass)

[0155] B: Sodium di-2-ethylhexyl sulfosuccinate (manufactured by Nippon Oil Co., Ltd., trade name "Rapiso A-80", solid content concentration 80% by mass)

[0156] C: Sodium N-acylmethyl taurate (manufactured by Nippon Oil Co., Ltd., trade name "Dyapon S", solid content concentration 13% by mass)

[0157] D: Sodium alkylallyl sulfosuccinate (manufactured by Sanyo Chemical Industry Co., Ltd., trade name "Elemino JS-20", solid content concentration 40% by mass)

[0158] E: Sodium lauryl sulfate (manufactured by Tokyo Chemical Industry Co., Ltd., reagent, solid content concentration 97% by mass)

[0159] F: Sodium polyoxyethylene disulfonate (manufactured by Nippon Emulsifier Co., Ltd., trade name "Newco 240", solid content concentration 30% by mass)

[0160] G: Disodium lauryl sulfosuccinate (manufactured by Sanyo Chemical Industry Co., Ltd., trade name "Beaulight SSS", solid content concentration 40% by mass)

[0161] H: Sodium N-lauroyl methyl alanine (manufactured by Nippon Oil Co., Ltd., trade name "Sofitel AS-L", solid content concentration 30% by mass)

[0162] I: Potassium oleate (manufactured by Nippon Oil Co., Ltd., trade name "Nonzal OK-1", solid content concentration 80% by mass)

[0163] J: Sodium salt of β-naphthalenesulfonic acid formaldehyde condensate (manufactured by Kao Corporation, trade name "Demor N", solid content concentration 100% by mass)

[0164] K: Lauryl dimethylaminoacetic acid betaine (manufactured by Nichiyu Corporation, trade name "Nissannon BL", solid content concentration 35% by mass)

[0165] L: Potassium rosinate (manufactured by Arakawa Chemical Industry Co., Ltd., trade name "Ronz K-25", solid content concentration 25% by mass)

[0166] Furthermore, the mass parts of each surfactant in each embodiment and comparative example are values ​​relative to 100 parts by mass of chlorosulfonated polyolefin in the chlorosulfonated polyolefin latex (specifically, manufactured by Sumitomo Seika Co., Ltd., trade name "Ceporex CSM-N" (chlorosulfonated polyethylene), with a solids concentration of 40% by mass). The addition part [phr] (per hundred rubber) in Table 1 represents this value.

[0167] It should be noted that the surfactant concentration (solid component concentration) in each of the above-mentioned surfactant products A to L is different. The mass fraction values ​​of each surfactant in the examples are values ​​calculated based on the amount of surfactant converted from the solid component concentration. For example, as described below, in Example 1, chlorosulfonated polyethylene latex (Sepoleux CSM-N) with a solid component concentration of approximately 40% by mass was used, compared to 2.5 parts by mass of sodium alkyl (C10-16) benzenesulfonate product (Newlex R) with a solid component concentration of 50% by mass. In this case, if the amount of Sepoleux CSM-N used is set to α parts by mass, the amount of chlorosulfonated polyethylene is 0.4α parts by mass, and the amount of sodium alkyl (C10-16) benzenesulfonate is 0.4α × 2.5 / 100 = 0.01α parts by mass. Furthermore, the amount of Newrex R used is 0.01α ÷ 0.5 = 0.02α parts by mass. In other words, the number of parts added [phr] in Table 1 represents the number of parts by mass of surfactant in the surfactant product used relative to 100 parts by mass of chlorosulfonated polyolefin contained in the chlorosulfonated polyolefin latex used.

[0168] In addition, Sepolex CSM-N contains 40% by mass of chlorosulfonated polyethylene, about 60% by mass of water, and a certain amount (about 0.1% to about 2% by mass) of polyoxyalkylene ether sulfate as an emulsifier in the form of a latex composition.

[0169] Evaluation methods

[0170] <Evaluation of whether solidification is possible>

[0171] Regarding whether solidification is possible, cases with a film thickness of 0.1 mm or more are considered to have solidified and are evaluated as ○, while cases with a film thickness of less than 0.1 mm are considered to have not solidified and are evaluated as ×.

[0172] <Film Strength>

[0173] Using Autograph (trade name "AGS-X" of Shimadzu Corporation), tensile tests were conducted on test pieces cut from the obtained film into JIS4 dumbbell shapes at a test temperature of 25°C and a tensile speed of 300 mm / min to determine the breaking strength and elongation at break.

[0174] <Chemical resistance of film>

[0175] A 1cm square test piece was cut from the obtained membrane and a pH test strip (manufactured by WATT MANN CO., LTD., pH test strip, SR type) was attached to the back. One drop of 95% sulfuric acid (manufactured by Fujifilm and Koichi Chemical Co., Ltd., reagent) was placed on the front of the membrane, and the membrane was left to stand for 1 hour. The change in pH test strip color after 1 hour was observed. No color change of pH test strip color was considered as no sulfuric acid transmission and was evaluated as ○, while a color change of pH test strip color was considered as sulfuric acid transmission and was evaluated as ×.

[0176] (Example 1)

[0177] <Preparation of Compositions for Impregnation Molding>

[0178] In a chlorosulfonated polyethylene latex (manufactured by Sumitomo Seika Co., Ltd., trade name "Sepoleex CSM-N", solids concentration of 40% by mass), 2.5 parts by mass of sodium alkyl (C10-16)benzenesulfonate (manufactured by Nippon Oil Co., Ltd., trade name "Newles R") were added relative to 100 parts by mass of chlorosulfonated polyethylene contained in the latex, and the mixture was stirred until completely dissolved to obtain a composition for impregnation molding. The viscosity of the obtained impregnation molding composition at 25°C was 56 mPa·s.

[0179] <Manufacturing of Impregnated Molded Body>

[0180] The ceramic mold was immersed in a 35% (w / w) calcium nitrate aqueous solution for 5 seconds and dried in a blower dryer at 120°C for 5 minutes. Then, the ceramic mold was immersed in the above-mentioned impregnation molding composition for 30 seconds to allow the rubber component to adhere to the ceramic mold, and then lifted from the impregnation molding composition. The ceramic mold with the rubber component attached was dried in a blower dryer at 70°C for 4 hours, and then immersed in warm water at 60°C for 1 hour to remove water-soluble components. Then, it was dried at 70°C for 1 hour and further heated at 120°C for 20 minutes. After cooling to room temperature, the film was peeled off from the ceramic mold to obtain the impregnated molded body. The obtained impregnated molded body was evaluated according to the following criteria. It should be noted that the ceramic mold used was a boat-shaped mold measuring 10cm × 1.5cm × 1cm (length × width × depth), and the above-described operation was performed using it to obtain the film (impregnated molded body).

[0181] (Examples 2-15)

[0182] In Example 1, the compounding agents, amounts, and impregnation times were changed to those listed in Table 1, and the same operation as in Example 1 was performed to obtain an impregnated molded article. It should be noted that in Examples 11-15, after adding surfactant 1 to chlorosulfonated polyethylene latex, surfactant 2 was further added and stirred until completely dissolved to obtain a composition for impregnation molding.

[0183] (Comparative Example 1)

[0184] A composition for impregnation molding is prepared by not specifically adding any substance to chlorosulfonated polyethylene latex (manufactured by Sumitomo Seika Co., Ltd., trade name "Sepoleex CSM-N", solid content concentration of 40% by mass).

[0185] (Comparative Examples 2-5)

[0186] In Example 1, the compounding agent, compounding amount, and impregnation time were changed to those recorded in Table 1, and the same operation as in Example 1 was performed to obtain an impregnated molded body.

[0187]

[0188] (Examples 16 and 17)

[0189] <Preparation of Compositions for Impregnation Molding>

[0190] Add 7.5 parts by weight of the surfactant formulated as shown in Table 2 to chlorosulfonated polyethylene latex (manufactured by Sumitomo Seika Co., Ltd., trade name "Seporex CSM-N", solids concentration of 40% by mass), and stir until completely dissolved or dispersed. It should be noted that this "7.5 parts by mass" is the same as the addition amount [phr] in Table 1, representing the mass of surfactant contained in the surfactant product relative to 100 parts by mass of chlorosulfonated polyolefin contained in the chlorosulfonated polyolefin latex used.

[0191] Then, 3 parts by weight of sodium dibutyldithiocarbamate aqueous solution (manufactured by Ouchi Shinsei Chemical Co., Ltd., trade name "Nocuser TP") and 10 parts by weight of triethylene glycol monobutyl ether (manufactured by Nippon Emulsifier Co., Ltd., trade name "Buchilt Rigrillol") were added, and the mixture was stirred until homogeneous to obtain a composition for impregnation molding. The viscosity of the obtained composition for impregnation molding at 25°C was 121 mPa·s.

[0192] <Manufacturing of Impregnated Molded Body>

[0193] The ceramic mold was immersed in a 35% (w / w) calcium nitrate aqueous solution for 5 seconds and dried in a blower dryer at 120°C for 5 minutes. Then, the ceramic mold was immersed in the above-mentioned impregnation molding composition for 5 minutes to allow the rubber component to adhere to the ceramic mold, and then lifted from the impregnation molding composition. The ceramic mold with the rubber component attached was dried in a blower dryer at 70°C for 4 hours, and then further heated at 120°C for 20 minutes. After cooling to room temperature, the film was peeled off from the ceramic mold to obtain the impregnated molded body. The obtained impregnated molded body was evaluated according to the above criteria. It should be noted that the ceramic mold used was rectangular, 20cm × 8cm, and the above-described operation using it yielded the film (impregnated molded body).

[0194]

[0195] Based on the above results, it can be seen that by adding specific surfactants to chlorosulfonated polyolefin latex, solidification can be achieved, resulting in impregnated molded bodies with excellent strength and chemical resistance.

[0196] Industrial availability

[0197] A method for manufacturing impregnated molded articles containing chlorosulfonated polyolefins without using sodium alginate is provided, along with the latex that can be used in this method and the impregnated molded articles containing chlorosulfonated polyolefins that do not require sodium alginate. This allows for the simple manufacture of impregnated molded articles with preferred strength and excellent chemical resistance. Furthermore, since impregnated molding does not use organic solvents, it is beneficial for environmental protection, as it allows for the production of impregnated molded articles such as gloves.

Claims

1. A chlorosulfonated polyolefin latex, comprising: (A) Chlorosulfonated polyolefins; (B) A surfactant having an anionic portion and a nonionic portion, wherein the nonionic portion comprises a polyoxyolefin chain and the anionic portion comprises a carboxylate, sulfonate, carbonate, sulfate, or phosphate. (C) At least one surfactant selected from the group consisting of amino acid surfactants, alkyl aryl sulfonic acid surfactants, alkyl sulfuric acid surfactants, and sulfosuccinic acid surfactants; and (D) Aqueous dispersion medium.

2. The latex according to claim 1, used for impregnation molding.

3. The latex according to claim 1 or 2, wherein, The content of (C) is 1 to 10 parts by mass relative to 100 parts by mass of (A).

4. The latex according to claim 1 or 2, wherein, Amino acid-type surfactants are at least one amino acid-type surfactant selected from the group consisting of glutamic acid-type surfactants, alanine-type surfactants, sarcosine-type surfactants, glycine-type surfactants, aspartic acid-type surfactants, and taurine-type surfactants. Alkyl aryl sulfonic acid surfactants are surfactants in which the alkyl group is a straight-chain or branched C8-C18 alkyl group and the aryl group is a phenylene or naphthylene group. Alkyl sulfate surfactants are at least one alkyl sulfate surfactant selected from the group consisting of alkyl sulfate surfactants and polyoxyethylene sulfonic acid surfactants. The sulfosuccinic acid type surfactant is at least one sulfosuccinic acid type surfactant selected from the group consisting of monoalkyl sulfosuccinic acid type surfactants, dialkyl sulfosuccinic acid type surfactants, and alkyl alkenyl sulfosuccinic acid type surfactants.

5. The latex according to claim 1 or 2, wherein, Chlorosulfonated polyolefin is chlorosulfonated polyethylene.

6. The latex according to claim 1 or 2, wherein, The surfactant in (B) is the compound shown in formula (I). R 1 -O-(CH2CHR 2 -O) n -R 3 (I) In equation (I), R 1 Indicates that by R 1a - indicates a group or is represented by R 1a -R 1b - indicates a group, R 1a - indicates an alkyl group with 6 to 20 carbon atoms, -R 1b - indicates phenylene, n represents an integer from 2 to 40, R 2 Same or different, indicating hydrogen or methyl, R 3 It can be represented as -SO3M or -COOM, where M represents an alkali metal.

7. An impregnated molded body, which is formed by impregnating the latex of claim 1 or 2 with a polyvalent metal salt as a coagulant.

8. The impregnated molded body according to claim 7, wherein the thickness is 0.1 mm or more.

9. The impregnated molded article according to claim 7, wherein, The dipped and molded body is a glove.

10. A method for manufacturing an impregnated molded article, comprising: A step of preparing an impregnation composition by mixing (C) at least one surfactant selected from the group consisting of amino acid surfactants, alkyl aryl sulfonic acid surfactants, alkyl sulfuric acid surfactants and sulfosuccinic acid surfactants into a latex, wherein the latex contains (A) chlorosulfonated polyolefin, (B) a surfactant having an anionic and nonionic portion, wherein the nonionic portion comprises a polyoxyethylene chain and the anionic portion comprises a carboxylate, sulfonate, carbonate, sulfate, or phosphate salt, and (D) an aqueous dispersion medium. The process of applying a coagulant to the surface of a mold having a desired shape; as well as The process of immersing a mold coated with a coagulant into an impregnation molding composition to form a solidified film.

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