Treatment agent for carbon fiber precursor and carbon fiber precursor

Abstract

To provide a treatment agent for a carbon fiber precursor that achieves the prevention of scum adhesion on a roller, the improvement of convergence of the carbon fiber precursor, and the enhancement of emulsion stability.SOLUTION: A treatment agent for a carbon fiber precursor according to the present invention comprises a saturated monoalcohol (A), a nonionic surfactant (B), and a smoothing agent (C), where the smoothing agent (C) comprises silicone (C1).SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a treating agent for a carbon fiber precursor and a carbon fiber precursor. [Background technology]

[0002] A commonly used method for producing carbon fibers is to spin a fibrous material and then calcinate the material, and this fibrous material is called a carbon fiber precursor. As the carbon fiber precursor, a fibrous material such as a polymer having a carbon fiber precursor treatment attached to the surface thereof may be used. Such a treatment is used for the purpose of improving the handleability of the carbon fiber precursor in various steps of producing carbon fibers.

[0003] International Publication No. 2018 / 163739 (Patent Document 1) discloses a treatment agent for acrylic fibers that contains an amino-modified silicone, a Bronsted acid compound, and an acetylene-based surfactant. Acrylic fibers for carbon fiber production produced by applying the treatment agent described in Patent Document 1 are less likely to deteriorate even when stored for a long period of time. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2018 / 163739 Summary of the Invention [Problem to be solved by the invention]

[0005] Carbon fiber precursors are generally wound up on a winding device such as a winder after successively undergoing processes such as spinning, drawing, drying, and application of a treatment agent. In this continuous process, the carbon fiber precursor passes through each process while being guided by a guide such as a roller. The carbon fiber precursor to which the treatment agent described in Patent Document 1 is applied has room for improvement in terms of preventing scum adhesion on the roller and improving the bundling property of the wound carbon fiber precursor. In addition, the dispersion (emulsion) of the treatment agent described in Patent Document 1 may cause gel formation in the oil bath due to its low mechanical stability, which may hinder the continuous production of carbon fiber precursors.

[0006] Therefore, there is a need for a treatment agent for carbon fiber precursors that prevents scum adhesion on rollers, improves the bundling ability of carbon fiber precursors, and improves emulsion stability, as well as a carbon fiber precursor to which the treatment agent has been applied. [Means for solving the problem]

[0007] The treating agent for carbon fiber precursor according to the present invention is The number of carbon atoms is 8 to 26. The composition is characterized in that it contains a saturated monoalcohol (A), a nonionic surfactant (B), and a smoothing agent (C), and the smoothing agent (C) contains a silicone (C1).

[0008] The carbon fiber precursor according to the present invention is characterized in that a treating agent for carbon fiber precursors is adhered to the carbon fiber precursor.

[0009] According to these configurations, it is possible to prevent scum from adhering to the roller, improve the bundling property of the carbon fiber precursor, and improve the emulsion stability. Furthermore, it is possible to obtain a carbon fiber precursor having good friction characteristics.

[0010] Preferred embodiments of the present invention will be described below. However, the scope of the present invention is not limited to the preferred embodiments described below.

[0011] In one embodiment of the treating agent for carbon fiber precursor according to the present invention, the saturated monoalcohol (A) preferably has a branched chain at the β-position of the hydroxyl group.

[0012] According to this configuration, the emulsion stability of the treatment agent for carbon fiber precursors is further improved.

[0013] In one embodiment of the treating agent for carbon fiber precursor according to the present invention, the proportion of the saturated monoalcohol (A) in the non-volatile content is preferably 0.1% by mass or more and 20% by mass or less.

[0014] According to this configuration, the bundling property of the carbon fiber precursor is further improved.

[0015] In one embodiment of the treating agent for carbon fiber precursor according to the present invention, the silicone (C1) preferably includes an amino-modified silicone.

[0016] According to this configuration, the friction characteristics of the carbon fiber precursor to which the treating agent for carbon fiber precursor has been applied are further improved.

[0017] In one embodiment of the treating agent for carbon fiber precursor according to the present invention, the nonionic surfactant (B) preferably contains an alkylene oxide adduct (B1) of a monoalcohol having a branched chain at the β-position of a hydroxy group.

[0018] According to this configuration, the emulsion stability of the treatment agent for carbon fiber precursors is further improved.

[0019] In one embodiment, the treatment agent for carbon fiber precursor according to the present invention preferably has a proportion of the saturated monoalcohol (A) in the non-volatile matter of 0.1 mass % or more and 20 mass % or less, a proportion of the nonionic surfactant (B) in the non-volatile matter of 10 mass % or more and 70 mass % or less, and a proportion of the smoothing agent (C) in the non-volatile matter of 29.9 mass % or more and 89.9 mass % or less.

[0020] According to this configuration, it is possible to prevent scum adhesion to the rollers, improve the bundling property of the carbon fiber precursor, and improve the emulsion stability, all at a high level.

[0021] Further features and advantages of the present invention will become more apparent from the following description of illustrative and non-limiting embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] The embodiments of the carbon fiber precursor treating agent and the carbon fiber precursor according to the present invention will be described below. In the following, an example in which the carbon fiber precursor treating agent according to the present invention (hereinafter, sometimes simply referred to as "treating agent") is applied to the treatment of a carbon fiber precursor will be described.

[0023] [Constitution of the treatment agent for carbon fiber precursor] The carbon fiber precursor treatment agent according to this embodiment contains, as non-volatile components, a saturated monoalcohol (A), a non-ionic surfactant (B), and a smoothing agent (C). The non-volatile components of the treatment agent refer to components that remain without volatilization when the treatment agent is heated in a hot air dryer at 105°C for 2 hours.

[0024] (Saturated monoalcohol) The saturated monoalcohol (A) is, as its name indicates, a saturated monoalcohol compound. That is, the saturated monoalcohol (A) is a compound in which one hydrogen atom of a saturated hydrocarbon is replaced with a hydroxyl group. The saturated monoalcohol (A) may be one type of saturated monoalcohol compound or a mixture of multiple types of saturated monoalcohol compounds.

[0025] The saturated monoalcohol (A) preferably has a carbon number of 8 or more and 26 or less. When the saturated monoalcohol (A) has a carbon number of 8 or more, it is preferable in that roller scum is unlikely to occur in the spinning process of spinning a carbon fiber precursor. When the saturated monoalcohol (A) has a carbon number of 26 or less, it is also preferable in that roller scum is unlikely to occur. The saturated monoalcohol (A) more preferably has a carbon number of 12 or more. The saturated monoalcohol (A) more preferably has a carbon number of 24 or less. When the saturated monoalcohol (A) is a mixture of multiple types of saturated monoalcohol compounds, it is preferable that the carbon number of at least one of the saturated monoalcohol compounds constituting the mixture is within the above range, and it is more preferable that the carbon numbers of all of the saturated monoalcohol compounds are within the above range.

[0026] The saturated monoalcohol (A) preferably has a branched chain at the β-position of the hydroxyl group. That is, a preferred embodiment of the saturated monoalcohol (A) is represented by the following general formula (1). [ka]

[0027] In the general formula (1), R 1 and R 2 is a saturated alkyl group. In a preferred embodiment, R 1 The number of carbon atoms, n, and R 2 The total number of carbon atoms (n+m) is 6 to 24. 1 and R 2 At least one of the saturated monoalcohol compounds (A) is preferably a saturated chain alkyl group, and more preferably both of the saturated monoalcohol compounds (A) are saturated chain alkyl groups. When the saturated monoalcohol (A) is a mixture of a plurality of saturated monoalcohol compounds, at least one of the saturated monoalcohol compounds constituting the mixture is preferably represented by general formula (1), and more preferably the carbon numbers of all the saturated monoalcohol compounds are represented by general formula (1).

[0028] Non-limiting examples of saturated monoalcohols (A) include 2-(1,3,3-trimethylbutyl)-5,7,7-trimethyl-1-octanol (carbon number: 18, n=9, m=7), 2-(4-methylhexyl)-8-methyl-1-decanol (carbon number: 18, n=9, m=7), 2-hexyl-1-decanol (carbon number: 16, n=8, m=6), 2-octyl-1-decanol (carbon number: 18, n=8, m=8), 2-hexyl-1-dodecanol (carbon number: 18, n=10, m=6), 2-octyl-1-dodecanol (carbon number: 20, n=10, m=8), 2-ethyl-1-hexanol (carbon number: 8, n=4, m=2), 2-butyl-1-octanol (carbon number: 12, n=6 , m=4), 2-decyl-1-tetradecanol (carbon number 24, n=12, m=10), 2-(4-methylnonyl)-7-methyl-1-tetradecanol (carbon number 25, n=13, m=10), 2-dodecyl-1-hexadecanol (carbon number 28, n=14, m=12), 2-tetradecyl-1-octadecanol (carbon number 32, n=16, m=14), 16-methyl-1-heptadecanol (carbon number 18), 1-dodecanol (carbon number 12), 1-nonanol (carbon number 9), 3,5,5-trimethyl-1-hexanol (carbon number 9), 1-octadecanol (carbon number 18), 1-hexanol (carbon number 6), and cyclohexanol (carbon number 6). Among the above-listed saturated monoalcohol compounds, those with the values ​​of n and m are examples of the saturated monoalcohol (A) represented by the general formula (1). A mixture of multiple types of saturated monoalcohol compounds selected from the above-listed compound groups is also an example of the saturated monoalcohol (A).

[0029] In the treatment agent according to the present embodiment, the ratio of the saturated monoalcohol (A) in the non-volatile content is preferably 0.1% by mass or more and 20% by mass or less. When the ratio of the saturated monoalcohol (A) is 0.1% by mass or more, it is preferable in that roller scum is unlikely to occur. When the ratio of the saturated monoalcohol (A) is 20% by mass or less, the bundling property of the carbon fiber precursor is likely to be high.

[0030] (Nonionic surfactant) The nonionic surfactant (B) may be any nonionic surfactant commonly used in the art. The nonionic surfactant (B) may be a single compound or a mixture of multiple compounds.

[0031] The nonionic surfactant (B) may be, for example, an alkylene oxide adduct of a compound having a hydroxy group, or a derivative thereof (such as an esterified product). The nonionic surfactant (B) preferably contains an alkylene oxide adduct (B1) of a monoalcohol having a branched chain at the β-position of the hydroxy group (hereinafter, sometimes referred to as nonionic surfactant (B1)).

[0032] A preferred embodiment of the nonionic surfactant (B1) is represented by the following general formula (2). [ka]

[0033] In the general formula (2), R 3 and R 4 is any hydrocarbon group, R 5 is an alkylene oxide residue. 3 and R 4 At least one of R is preferably a saturated alkyl group, and more preferably both are saturated alkyl groups. 3 and R 4 At least one of R is preferably a chain alkyl group, and more preferably both are chain alkyl groups. 3 and R 4 It is particularly preferable that both of the groups are saturated chain alkyl groups.

[0034] R 5 is the ethylene oxide residue (-(C2H4O) x -) and propylene oxide residue (-(C3H6) x -) or both.

[0035] When the nonionic surfactant (B) is a mixture of multiple types of nonionic surfactants, it is preferable that at least one of the nonionic surfactants constituting the mixture is nonionic surfactant (B1) (general formula (2)), and it is more preferable that all of the nonionic surfactants are nonionic surfactant (B1) (general formula (2)).

[0036] Non-limiting examples are given below for cases where the non-ionic surfactant (B) is an alkylene oxide adduct of a compound having a hydroxy group. The compounds listed as non-limiting examples of the saturated monoalcohol (A) above are all examples of compounds having a hydroxy group that give the non-ionic surfactant (B). That is, examples of compounds having a hydroxy group include 2-(1,3,3-trimethylbutyl)-5,7,7-trimethyl-1-octanol, 2-(4-methylhexyl)-8-methyl-1-decanol, 2-hexyl-1-decanol, 2-octyl-1-decanol, 2-hexyl-1-dodecanol, 2-octyl-1-dodecanol, 2-ethyl-1-hexanol, and 2-butyl-1-octanol. , 2-dodecyl-1-tetradecanol, 2-(4-methylnonyl)-7-methyl-1-tetradecanol, 2-dodecyl-1-hexadecanol, 2-tetradecyl-1-octadecanol, 16-methyl-1-heptadecanol, 1-dodecanol, 1-nonanol, 3,5,5-trimethyl-1-hexanol, 1-octadecanol, 1-hexanol, and cyclohexanol are exemplified. Other examples of compounds having a hydroxyl group include 11-methyl-undecanol, tetradecyl alcohol, tridecyl alcohol, dodecyl alcohol, secondary tetradecyl alcohol, secondary tridecyl alcohol, tristyrenated phenol, distyrenated phenol, and bisphenol A. Non-limiting examples of alkylene oxides include ethylene oxide and propylene oxide.

[0037] Therefore, the nonionic surfactant (B) may be, for example, a compound obtained by reacting one or more of the above-listed compounds having hydroxyl groups with one or more of the above-listed alkylene oxides in a predetermined molar ratio. Due to the nature of the alkylene oxide addition reaction, the product of the reaction is generally a mixture of multiple compounds with different numbers of alkylene oxides added. Therefore, the nonionic surfactant (B) may be specified by the type of the hydroxyl group-containing compound and alkylene oxide used as the substrate, and the molar ratio thereof.

[0038] The nonionic surfactant (B) may be an alkylene oxide adduct of an amine compound or a derivative thereof (such as an esterified product). A non-limiting example of this case is an ethylene oxide adduct of dodecylamine.

[0039] In the treatment agent according to the present embodiment, the proportion of the nonionic surfactant (B) in the nonvolatile content is preferably 10% by mass or more and 70% by mass or less. If the proportion of the nonionic surfactant (B) is 10% by mass or more and 70% by mass or less, it is preferable in that emulsification is facilitated.

[0040] (Smoothing agent) The smoothing agent (C) includes a silicone (C1). The smoothing agent (C) may be one type of compound or a mixture of multiple types of compounds. When the smoothing agent (C) includes multiple types of compounds, it may be a mixture of multiple types of silicones (C1), or a mixture of one or multiple types of silicones (C1) and one or multiple types of non-silicone smoothing agents (C2). The smoothing agent (C) preferably includes 15% by mass or more of silicone (C1).

[0041] Silicone (C1) can be specified by its kinematic viscosity at 25° C. measured with a Cannon-Fenske viscometer. The kinematic viscosity of silicone at 25° C. is 80 mm 2 / s or more 2000mm 2 / s or less.

[0042] The silicone (C1) preferably contains an amino-modified silicone. The modification in the amino-modified silicone may be performed in any manner. Therefore, the amino-modified silicone may be a compound in which an amino group is introduced to the end of the silicone main chain, the side chain, or both. When an amino group is introduced to the end of the silicone main chain, the amino group may be introduced to both ends, or only one end. Furthermore, the amino group to be introduced may be any, and may be a monoamine, a diamine, an amino polyether, or the like. When the end group is not modified, the end group may be a hydroxyl group, a methoxy group, or the like.

[0043] The amino-modified silicone can be specified by the amino equivalent (g / mol) calculated from the total amine value (KOH-mg / g) measured by precisely weighing 1 g into a mixed solution of 60 mL of acetone and 20 mL of normal hexane and titrating it with a perchloric acid solution of known concentration. The amino equivalent of the amino-modified silicone can be 2000 or more and 8000 or less.

[0044] The silicone (C1) may be a modified silicone other than the amino-modified silicone. Examples of such modified silicone include polyether-modified silicone, carboxyl-modified silicone, hydroxyl-modified silicone, and alkyl-modified silicone.

[0045] Non-silicone smoothing agent (C2) can be any non-silicone smoothing agent commonly used in the art.Non-limiting examples of non-silicone smoothing agent (C2) include the reaction product of polybutenyl succinic anhydride and triethylenetetramine, the reaction product of polybutenyl-modified phenol, formaldehyde and triethylenetetramine, and mineral oil.

[0046] In the treatment agent according to the present embodiment, the ratio of the smoothing agent (C) in the non-volatile content is preferably 29.9% by mass or more and 89.9% by mass or less. When the ratio of the smoothing agent (C) is 29.9% by mass or more, it is preferable in terms of friction characteristics. When the ratio of the smoothing agent (C) is 89.9% by mass or less, it is preferable in terms of emulsifiability.

[0047] (Other Ingredients) The treatment agent according to this embodiment may contain other components than the saturated monoalcohol (A), the nonionic surfactant (B), and the smoothing agent (C). Examples of such other components include, but are not limited to, preservatives, antistatic agents, antioxidants, ultraviolet absorbers, and defoamers.

[0048] In addition, as a typical embodiment in which the treatment agent is used to treat a carbon fiber precursor, a non-volatile content such as a saturated monoalcohol (A) is diluted with a diluent. Such a diluent is also an example of another component. Examples of diluents include water (tap water, industrial water, ion-exchanged water, distilled water, etc.), acetone, methyl ethyl ketone, N-methyl-2-pyrrolidone, etc., but are not limited thereto. The concentration of the non-volatile content in the treatment agent in an embodiment in which the non-volatile content is diluted with a diluent is not particularly limited, but may be, for example, 10% by mass or more and 60% by mass or less. As described above, the non-volatile content of the treatment agent refers to the components that remain without volatilization after the treatment agent is heated in a hot air dryer at 105°C for 2 hours, and the concentration refers to the ratio of the mass of the non-volatile content in the treatment agent to the mass of the treatment agent.

[0049] [Method for producing a treatment agent for carbon fiber precursor] The treatment agent according to the present embodiment can be obtained by mixing the saturated monoalcohol (A), the nonionic surfactant (B), the smoothing agent (C), and any other components by a known method. For example, the treatment agent can be produced by adding water to the saturated monoalcohol (A), the nonionic surfactant (B), the smoothing agent (C), and any other components while stirring at a temperature between 20°C and 90°C for 5 hours.

[0050] [Carbon fiber precursor] The carbon fiber precursor according to the present embodiment is an embodiment in which the treatment agent according to the present embodiment is attached to a fiber material generally used as a carbon fiber precursor. The fiber material here refers to a fibrous material that becomes carbon fiber through a firing process, and may be polyacrylonitrile-based fiber, polyamide-based fiber, polyester-based fiber, polyolefin-based fiber, cellulose-based fiber, lignin-based fiber, phenolic resin, pitch, or a combination of these.

[0051] The method for applying the treatment agent to the textile material can be any method commonly used in the art for applying this type of treatment agent to textile materials. That is, the immersion oiling method, the spray oiling method, the roller oiling method, the guide oiling method, etc. can be used. When applying each method, the treatment agent can be appropriately diluted with a solvent such as water.

[0052] In the carbon fiber precursor according to this embodiment, the amount of the treatment agent attached is not particularly limited. For example, it is preferable that the treatment agent is attached in an amount of 0.3 mass % to 3 mass % based on the entire carbon fiber precursor to which the treatment agent is attached.

[0053] Other embodiments The present invention may be a treatment agent for carbon fiber precursors, comprising a saturated monoalcohol (A), a nonionic surfactant (B), and a smoothing agent (C), wherein the smoothing agent (C) contains a silicone (C1).

[0054] In the treating agent for carbon fiber precursors, the saturated monoalcohol (A) may have a carbon number of 8 or more and 26 or less. According to this configuration, roller scum is particularly unlikely to occur.

[0055] Regarding other configurations, it should be understood that the embodiments disclosed in this specification are illustrative in all respects and that the scope of the present invention is not limited thereto. A person skilled in the art would easily understand that appropriate modifications are possible without departing from the spirit of the present invention. Therefore, other embodiments modified without departing from the spirit of the present invention are naturally included in the scope of the present invention. EXAMPLES

[0056] The present invention will be further described below with reference to examples, but the present invention is not limited to the following examples.

[0057] [Preparation of treatment agent for carbon fiber precursor] The following methods were used to prepare the samples shown in Tables 1 to 3 in the following examples. 19, Reference examples 1-5, And, treating agents for carbon fiber precursors of Comparative Examples 1 to 4 were obtained.

[0058] (1) Reagents (1-1) Alcohol The following alcohols A-1 to A-18 and a-1 to a-3 were used as the alcohols. Among these, the alcohols A-1 to A-18 are saturated monoalcohols. The alcohols A-1 to A-11 are saturated monoalcohols represented by the general formula (1). The carbon number and n and m of each alcohol are the same as those in the above embodiment.

[0059] A-1: 2-(1,3,3-trimethylbutyl)-5,7,7-trimethyl-1-octanol (carbon number 18, n=9, m=7) A-2: 2-(4-methylhexyl)-8-methyl-1-decanol (carbon number 18, n=9, m=7) A-3: 2-hexyl-1-decanol (carbon number 16, n=8, m=6) A-4: A 50:50 molar mixture of 2-octyl-1-decanol (carbon number 18, n=8, m=8) and 2-hexyl-1-dodecanol (carbon number 18, n=10, m=6) A-5: 2-octyl-1-dodecanol (carbon number 20, n=10, m=8) A-6: 2-Ethyl-1-hexanol (carbon number 8, n=4, m=2) A-7: 2-Butyl-1-octanol (carbon number 12, n=6, m=4) A-8: 2-Decyl-1-tetradecanol (carbon number 24, n=12, m=10) A-9: 2-(4-methylnonyl)-7-methyl-1-tetradecanol (carbon number 25, n=13, m=10) A-10: 2-dodecyl-1-hexadecanol (carbon number 28, n=14, m=12) A-11: 2-tetradecyl-1-octadecanol (carbon number 32, n=16, m=14) A-12: 16-methyl-1-heptadecanol (carbon number 18) A-13: 1-dodecanol (carbon number 12) A-14: 1-nonanol (carbon number 9) A-15: 3,5,5-trimethyl-1-hexanol (carbon number 9) A-16: 1-Octadecanol (carbon number 18) A-17: 1-Hexanol (carbon number 6) A-18: Cyclohexanol (carbon number 6) a-1: 3,6-dimethyl-4-octyne-3,6-diol a-2: cis-9-octadecene-1-ol a-3: 9Z,12Z-octadecadien-1-ol

[0060] (1-2) Nonionic surfactants The following nonionic surfactants B-1 to B-17 were used as the nonionic surfactant. All of the nonionic surfactants correspond to the nonionic surfactant (B) according to the above embodiment, and among them, nonionic surfactants B-1 to B-3 correspond to the nonionic surfactant (B1) represented by general formula (2). However, the manufacturing method shown for each nonionic surfactant is only an example, and even if the nonionic surfactant is manufactured by a method different from the method exemplified below, the embodiment can be used. , reference example, And the results of the comparative examples remain unchanged.

[0061] (Nonionic surfactant B-1) 2-Hexyl-1-decanol was reacted with ethylene oxide in a molar ratio of 1:3 to obtain a nonionic surfactant B-1, which is an ethylene oxide adduct of 2-hexyl-1-decanol.

[0062] (Nonionic surfactant B-2) 2-Hexyl-1-decanol was reacted with ethylene oxide in a molar ratio of 1:6 to obtain a nonionic surfactant B-2, which is an ethylene oxide adduct of 2-hexyl-1-decanol.

[0063] (Nonionic surfactant B-3) 2-Hexyl-1-decanol was reacted with ethylene oxide in a molar ratio of 1:9 to obtain a nonionic surfactant B-3, which is an ethylene oxide adduct of 2-hexyl-1-decanol.

[0064] (Nonionic surfactant B-4) Dodecyl alcohol and ethylene oxide were reacted in a molar ratio of 1:9 to obtain a nonionic surfactant B-4, which is an ethylene oxide adduct of dodecyl alcohol.

[0065] (Nonionic surfactant B-5) 11-Methyl-undecanol was reacted with ethylene oxide in a molar ratio of 1:12 to obtain a nonionic surfactant B-5, which is an ethylene oxide adduct of 11-methyl-undecanol.

[0066] (Nonionic surfactant B-6) Tetradecyl alcohol and ethylene oxide were reacted in a molar ratio of 1:7 to obtain a nonionic surfactant B-6, which is an ethylene oxide adduct of tetradecyl alcohol.

[0067] (Nonionic surfactant B-7) Tridecyl alcohol and ethylene oxide were reacted in a molar ratio of 1:15 to obtain a nonionic surfactant B-7, which is an ethylene oxide adduct of tridecyl alcohol.

[0068] (Nonionic surfactant B-8) Dodecyl alcohol and ethylene oxide were reacted in a molar ratio of 1:20 to obtain a nonionic surfactant B-8, which is an ethylene oxide adduct of dodecyl alcohol.

[0069] (Nonionic surfactant B-9) Secondary tetradecyl alcohol and ethylene oxide were reacted in a molar ratio of 1:10 to obtain nonionic surfactant B-9, which is an ethylene oxide adduct of secondary tetradecyl alcohol.

[0070] (Nonionic surfactant B-10) Secondary tridecyl alcohol and ethylene oxide were reacted in a molar ratio of 1:9 to obtain nonionic surfactant B-10, which is an ethylene oxide adduct of secondary tridecyl alcohol.

[0071] (Nonionic surfactant B-11) Dodecyl alcohol was reacted with ethylene oxide and propylene oxide in a molar ratio of 1:2:6 to obtain the nonionic surfactant B-11, which is a random adduct of ethylene oxide and propylene oxide with dodecyl alcohol.

[0072] (Nonionic surfactant B-12) Tristyrenated phenol was reacted with ethylene oxide and propylene oxide in a molar ratio of 1:15:9 to obtain the nonionic surfactant B-12, which is an ethylene oxide-propylene oxide random adduct of tristyrenated phenol.

[0073] (Nonionic surfactant B-13) Distyrenated phenol was reacted with ethylene oxide and propylene oxide in a molar ratio of 1:18:5 to obtain the nonionic surfactant B-13, which is an ethylene oxide-propylene oxide random adduct of distyrenated phenol.

[0074] (Nonionic surfactant B-14) Bisphenol A was reacted with ethylene oxide in a molar ratio of 1:18 to obtain a nonionic surfactant B-14, which is an ethylene oxide adduct of bisphenol A.

[0075] (Nonionic surfactant B-15) Tristyrenated phenol was reacted with ethylene oxide in a molar ratio of 1:30 to obtain nonionic surfactant B-15, which is an ethylene oxide adduct of tristyrenated phenol.

[0076] (Nonionic surfactant B-16) Dodecyl alcohol and ethylene oxide were reacted in a molar ratio of 1:6 to obtain a nonionic surfactant B-16, which is an ethylene oxide adduct of dodecyl alcohol.

[0077] (Nonionic surfactant B-17) Dodecylamine and ethylene oxide were reacted in a molar ratio of 1:10 to obtain a nonionic surfactant B-17, which is an ethylene oxide adduct of dodecylamine.

[0078] (1-3) Smoothing agent The following silicones C1-1 to C1-11 and non-silicone smoothing agents C2-1 to C2-5 were used as the smoothing agents. Of these, silicones C1-1 to C1-7 were amino-modified silicones.

[0079] (Silicone C1-1) Dynamic viscosity at 25°C is 80mm 2 The amino-modified silicone used had an amino equivalent of 4400 and a diamino side chain amino group.

[0080] (Silicone C1-2) The kinetic viscosity at 25°C is 800mm 2 The amino-modified silicone used had an amino equivalent of 3000 and a monoamino side chain amino group.

[0081] (Silicone C1-3) The kinetic viscosity at 25°C is 1200mm 2 The silicone used was an amino-modified silicone having an amino equivalent of 5000 and a diamino side chain.

[0082] (Silicone C1-4) The kinetic viscosity at 25°C is 2000mm 2 The silicone used was an amino-modified silicone having a molecular weight of 7000 and an amino equivalent of 7000, the amino groups of which were diamino groups on the side chains, and which was methoxy-type at both ends.

[0083] (Silicone C1-5) The kinetic viscosity at 25°C is 250mm 2 The amino-modified silicone used had a molecular weight of 1,000 and an amino equivalent of 2,000. The amino groups were diamino-type side chains.

[0084] (Silicone C1-6) Dynamic viscosity at 25°C is 1500mm 2 The amino-modified silicone used had a molecular weight of 1.0 / s, an amino equivalent of 8000, a side-chain monoamino type amino group, and a mixed type terminal group of a hydroxyl group and a methoxy group.

[0085] (Silicone C1-7) Dynamic viscosity at 25°C is 90mm 2 The amino-modified silicone used had an amino equivalent of 2200 and was diamino-type at both ends.

[0086] (Silicone C1-8) Dynamic viscosity at 25°C is 300mm 2 The side-chain type polyether-modified silicone used had a weight ratio of dimethyl silicone main chain / ethylene oxide / propylene oxide of 50 / 20 / 30.

[0087] (Silicone C1-9) The kinetic viscosity at 25°C is 1000mm 2 The ABn type polyether modified silicone was used, which has a dimethyl silicone main chain / ethylene oxide weight ratio of 70 / 30.

[0088] (Silicone C1-10) The kinetic viscosity at 25°C is 1000mm 2The polymer used was a dimethyl silicone with both ends blocked, i.e. / s.

[0089] (Silicone C1-11) Dynamic viscosity at 25°C is 80mm 2 The silicone was prepared using dimethyl silicone having OH groups at both ends, i.e., / s.

[0090] (Non-silicone smoothing agent C2-1) A compound obtained by reacting polybutenyl succinic anhydride, the polybutene portion of which has a number average molecular weight of 2000, with triethylenetetraamine was used.

[0091] (Non-silicone smoothing agent C2-2) A compound obtained by reacting phenol modified with a polybutenyl group, the number average molecular weight of which is 1500 in the polybutene portion, with formaldehyde and triethylenetetraamine was used.

[0092] (Non-silicone smoothing agent C2-3) It has a composition of 0.5% aromatics, 25% naphthenes, and 74.5% paraffins, and has a kinetic viscosity of 18mm at 30°C. 2 A mineral oil having a viscosity of 100:1 was used.

[0093] (Non-silicone smoothing agent C2-4) It has a composition of 2% aromatics, 40% naphthenes, and 58% paraffins, and its kinetic viscosity at 30°C is 9mm 2 A mineral oil having a viscosity of 100:1 was used.

[0094] (Non-silicone smoothing agent C2-5) It has a composition of 0.1% aromatics, 30% naphthenes, and 69.9% paraffins, and has a kinetic viscosity of 46mm at 30°C. 2 A mineral oil having a viscosity of 100:1 was used.

[0095] (1-4) Other ingredients The following were used as other components: D-1: Acetic acid D-2: Trimethyloctylammonium dimethyl phosphate Diluent: Ion-exchanged water

[0096] (2) Preparation of carbon fiber treatment agent (Preparation of Example 1) 10 parts by mass of alcohol A-1, 5 parts by mass of nonionic surfactant B-1, 5 parts by mass of nonionic surfactant B-4, 10 parts by mass of nonionic surfactant B-7, and 70 parts by mass of silicone C1-1 were weighed and put into a beaker. After thoroughly mixing the above components, 233 parts by mass of ion-exchanged water was gradually added while stirring to prepare the carbon fiber precursor treatment agent of Example 1.

[0097] (Other Examples , reference example, and preparation of comparative examples) Except for changing the types and parts by mass of the reagents to be mixed, the treating agent for carbon fiber precursor of each example was prepared in the same manner as in Example 1. The preparation conditions for all examples including Example 1 are shown in Tables 1 to 3 below.

[0098] [Evaluation of Treatment Agents for Carbon Fiber Precursors] (1) Preparation of carbon fiber (1-1) Preparation of fiber materials A copolymer with an intrinsic viscosity of 1.80 consisting of 95% by mass of acrylonitrile, 3.5% by mass of methyl acrylate, and 1.5% by mass of methacrylic acid was dissolved in dimethylacetamide (DMAC) to prepare a spinning dope with a polymer concentration of 21.0% by mass and a viscosity of 500 poise at 60°C. The spinning dope was discharged at a draft ratio of 0.8 from a spinneret with a hole diameter (inner diameter) of 0.075 mm and 12,000 holes into a coagulation bath of a 70% by mass aqueous solution of DMAC kept at a spinning bath temperature of 35°C. The coagulated yarn was stretched 5 times in a water washing tank while removing the solvent, to prepare a water-swollen acrylic fiber strand.

[0099] (1-2) Preparation of carbon fiber precursor For the acrylic fiber strands created, , reference example,A 3% ion-exchange aqueous solution of the carbon fiber precursor treatment agent of each of the examples and Comparative Examples was added by immersion so that the amount of the treatment agent attached was 1 mass % (not including the solvent). Thereafter, the acrylic fiber strand to which the treatment agent was attached was subjected to a drying and densifying treatment with a heating roller at 150°C, and further subjected to drawing by 1.7 times between heating rollers at 170°C, and then wound up on a yarn tube to obtain a carbon fiber precursor.

[0100] (2) Evaluation of the amount of scum generated Working Example , reference example, For each of the treatment agents of the comparative examples, the carbon fiber precursors were continuously produced by the above procedure (1), and the presence or absence and the degree of scum accumulation on the heating roller in the drying and densifying process were observed. Depending on the observation results, they were classified into the following three levels. A: There was little scum accumulation on the heating roller, and continuous operation was possible for more than 7 days without stopping due to thread breakage or other reasons. B: Although some scum accumulation was observed on the heating roller, continuous operation was possible for 3 to 7 days without stopping due to thread breakage or the like, and without cleaning. C: There was a lot of scum accumulation on the heating roller, and operations had to be stopped due to thread breakage, etc., and cleaning was required within 3 days.

[0101] (3) Evaluation of winding convergence Working Example , reference example, The treatment agents of the examples of the comparative examples were classified into the following three levels according to the state of the work when winding the carbon fiber precursor on the winder. A: There was almost no yarn breakage, and continuous winding was possible without stopping operations. B: Although some yarn breakage was observed, continuous winding was possible without stopping operations. C: The line broke badly and became wrapped around the traverse, making it necessary to stop operations.

[0102] (4) Emulsion stability Working Example , reference example,A 3% ion-exchange aqueous solution of each of the treatment agents of the examples and the comparative examples was circulated in an oil bath by a pump, and the state of the aqueous solution was visually observed. Depending on the observation results, it was classified into the following four levels. A: After 7 days, no gel formation was observed and smooth continuous operation was possible. B: After 7 days, a small amount of gel was observed, but smooth continuous operation was possible without cleaning the oil bath. C: After 7 days, gel was observed and cleaning was required to remove the gel from the oil bath, but continuous operation was possible. D: After 7 days, a lot of gel had formed and the operation had to be stopped for cleaning of the oil bath.

[0103] (5)Friction characteristics A 100g tension was applied to a 12K (12,000 pieces) carbon fiber precursor bundle with 1% treatment applied, and a 1cm chrome matte pin was rotated at 200 rpm for 10 minutes. The state of the carbon fiber precursor bundle was observed. The results were classified into the following three levels. A: No broken yarn or associated fluff was observed with the naked eye. B: Thread breakage and a small amount of associated fuzz (1-10 strands) were observed. C: Many broken threads and associated fuzz (11 or more threads) were observed.

[0104] 〔result〕 Working Example , reference example, The raw material composition and the results of each evaluation of each example and comparative example are shown in Tables 1 to 3.

[0105] Table 1: Examples 1 to 12 [Table 1]

[0106] Table 2: Example 13 19 and Reference Examples 1 to 5 [Table 2]

[0107] Table 3: Comparative Examples 1 to 4 [Table 3] [Industrial Applicability]

[0108] The present invention can be used, for example, in the production of carbon fiber precursors.

Claims

1. The composition contains a saturated monoalcohol (A), a nonionic surfactant (B), and a smoothing agent (C), The treatment agent for carbon fiber precursors, wherein the smoothing agent (C) contains a silicone (C1).

2. The treating agent for carbon fiber precursors according to claim 1 , wherein the saturated monoalcohol (A) has 8 or more and 26 or less carbon atoms.

3. The treatment agent for carbon fiber precursors according to claim 1 , wherein the saturated monoalcohol (A) has a branched chain at the β-position of a hydroxyl group.

4. The treatment agent for carbon fiber precursors according to claim 1 , wherein the saturated monoalcohol (A) accounts for 0.1 mass % or more and 20 mass % or less of the non-volatile content.

5. The treatment agent for carbon fiber precursors according to claim 1 , wherein the silicone (C1) comprises an amino-modified silicone.

6. 2. The treatment agent for carbon fiber precursors according to claim 1, wherein the nonionic surfactant (B) comprises an alkylene oxide adduct (B1) of a monoalcohol having a branched chain at the β-position of a hydroxy group.

7. In the non-volatile matter, The proportion of the saturated monoalcohol (A) is 0.1% by mass or more and 20% by mass or less, The proportion of the nonionic surfactant (B) is 10% by mass or more and 70% by mass or less, and The treatment agent for carbon fiber precursors according to claim 1 , wherein the ratio of the smoothing agent (C) is 29.9 mass % or more and 89.9 mass % or less.

8. A carbon fiber precursor having the treating agent for carbon fiber precursors according to any one of claims 1 to 7 adhered thereto.

Images