JP5914780B1 - Acrylic fiber treatment agent and its use - Google Patents

Abstract

The objective of this invention is providing the acrylic fiber processing agent which can make the bundling property of the fiber bundle in carbon fiber manufacture, the fusion prevention between fibers, and the stable operativity compatible. The acrylic fiber treating agent of the present invention contains a compound (A) represented by the following general formula (1) and a polyether compound (B) having a weight average molecular weight of 8000 to 25000, and the compound (A) and the polyether compound. The total weight ratio of (B) is 50 to 99% by weight. In the formula (1), R1 and R2 are each independently a hydrogen atom or an alkyl group, AO is an oxyalkylene group having 2 to 4 carbon atoms, and m and n are each independently And a number of 1 or more.)

Description

  The present invention relates to an acrylic fiber treatment agent and use thereof. More specifically, the treatment agent used when producing the acrylic fiber, the acrylic fiber for producing carbon fiber using the treatment agent (hereinafter sometimes referred to as a precursor), and the carbon fiber using the treatment agent It relates to a manufacturing method.

Carbon fibers are widely used for aerospace applications, sports applications, general industrial applications and the like as reinforcing fibers for composite materials with plastics called matrix resins, utilizing their excellent mechanical properties.
As a method for producing carbon fiber, a method is generally used in which a precursor is converted to a flame-resistant fiber in an oxidizing atmosphere at 200 to 300 ° C., and subsequently carbonized in an inert atmosphere at 300 to 2000 ° C. At the time of firing by these high heats, there is a problem that fusion of single fibers occurs and the quality and quality of the obtained carbon fibers are deteriorated.

  In order to prevent this fusion, a silicone-based treatment agent having a silicone compound as a main component and having excellent heat resistance and excellent releasability due to smoothness between fibers and fibers, particularly amino which can further improve heat resistance by a crosslinking reaction. Many techniques for applying a modified silicone-based treatment agent to a precursor have been proposed (for example, Patent Document 1) and are widely used industrially.

However, on the other hand, the silicone treatment agent that has been subjected to adhesion treatment drops off from the fiber to become an adhesive, which accumulates on a drying roller, a guide, etc. in the precursor manufacturing process, and the fibers are seized or broken. There was a problem of causing a decrease in sex. In addition, some of the scales generate silicon oxide in the oxidizing atmosphere of the flameproofing process, and when nitrogen is used as an inert gas in the inert atmosphere of the carbonization process, silicon nitride is generated. It accumulates, and has had the problem of reducing operability and operability, and causing damage to the firing furnace.
Furthermore, the excellent releasability due to the fiber-to-fiber smoothness of the silicone treatment agent works effectively to prevent fusion between single fibers, while a large number of fiber bundles run simultaneously in parallel. In this case, the width of each fiber bundle expands due to the smoothness of the silicone treatment agent, so that the distance between adjacent fiber bundles is narrowed, and in some cases, there is a disadvantage that fluff is generated due to the interference.

  In order to avoid these problems, treatment agents with a reduced content of silicone compounds, treatment agents that do not use silicone compounds, and the like have been proposed. For example, a treatment agent (for example, Patent Document 2) containing a fatty acid ester of a bisphenol A-based alkylene oxide adduct as a main component and a reduced amino-modified silicone content, or a fatty acid ester of a bisphenol A alkylene oxide adduct There is a treatment agent (for example, Patent Document 3) which has a main component and does not use a silicone compound.

Japanese Unexamined Patent Publication No. 2002-371477 Japanese Unexamined Patent Publication No. 2005-89884 Japanese Unexamined Patent Publication No. 2004-143645

However, these treatment agents are effective in suppressing the problems such as the above-mentioned operability caused by the silicone compound, but the fiber bundles at the time of winding and unwinding in the precursor yarn-making process, In addition, there is a drawback in that the bundleability of the fiber bundles at the inlet and outlet of the flameproofing furnace in the flameproofing process is insufficient.
In view of such a conventional technical background, an object of the present invention is to provide an acrylic fiber treatment agent capable of achieving both the bundleability of fiber bundles, prevention of fusion between fibers and stable operability in carbon fiber production, and the treatment agent. An object of the present invention is to provide an acrylic fiber for producing carbon fiber using the above and a method for producing carbon fiber using the treating agent.

  As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that a conventional treating agent containing a fatty acid ester of an alkylene oxide adduct of bisphenol A has a large amount of nonionic properties to emulsify the ester in an aqueous system. A surfactant (emulsifier) was required, and it was found out that the bundledness of the fiber bundle was deteriorated in the precursor yarn-making process and the flameproofing process due to the influence of this large amount of emulsifier. And if it is a processing agent containing a specific component as a main component, it is possible to reduce the content of a nonionic surfactant and a silicone compound used as an emulsifier in the processing agent, fiber bundle convergence in carbon fiber production, The inventors have found that it is possible to achieve both fusion prevention between fibers and stable operability, and the present invention has been achieved.

  That is, the acrylic fiber treatment agent of the present invention contains a compound (A) represented by the following general formula (1) and a polyether compound (B) having a weight average molecular weight of 8000 to 25000, and occupies the nonvolatile content of the treatment agent. The total weight ratio of the compound (A) and the polyether compound (B) is 50 to 99% by weight.

（式（１）中、Ｒ^１及びＲ^２は、それぞれ独立して、水素原子又はアルキル基である。ＡＯは炭素数２〜４のオキシアルキレン基である。ｍ及びｎは、それぞれ独立して、１以上の数である。）

(In Formula (1), R ¹ and R ² are each independently a hydrogen atom or an alkyl group. AO is an oxyalkylene group having 2 to 4 carbon atoms. M and n are each independently 1 or more.)

  The weight ratio (A / B) between the compound (A) and the polyether compound (B) is preferably 90/10 to 20/80.

  The acrylic fiber treatment agent of the present invention preferably further contains a nonionic surfactant (C) represented by the following general formula (2).

（式（２）中、Ｒ^３は炭素数８〜２０の炭化水素基である。−Ｘ−は、−Ｏ−、−ＣＯＯ−又は−ＣＯＮＨ−である。ＥＯはオキシエチレン基、ＰＯはオキシプロピレン基である。ａ及びｂは平均付加モル数を表わし、ａは３〜２０、ｂは０〜６である。なお、ＥＯ群とＰＯ群の付加形態はブロックでもランダムでもよい。Ｒ^４は水素原子又は炭素数１〜６の炭化水素基である。）

(In the formula (2), R ³ is a hydrocarbon group having 8 to 20 carbon atoms. -X- is -O-, -COO- or -CONH-. EO is an oxyethylene group, and PO is an oxy group. A and b represent the average number of moles added, a is from 3 to 20, and b is from 0 to 6. The addition form of the EO group and the PO group may be block or random, R ⁴ is It is a hydrogen atom or a C1-C6 hydrocarbon group.)

  The weight ratio of the nonionic surfactant (C) in the non-volatile content of the treatment agent is preferably 0.5 to 15% by weight.

The acrylic fiber treatment agent of the present invention preferably further contains a modified silicone (D) having a modifying group containing a nitrogen atom.
It is preferable that the weight ratio of the modified silicone (D) in the nonvolatile content of the treatment agent is 5 to 40% by weight.

  The acrylic fiber for producing carbon fiber of the present invention is produced by attaching the above-mentioned acrylic fiber treating agent to the raw acrylic fiber of the acrylic fiber for producing carbon fiber.

  The carbon fiber production method of the present invention includes a yarn production process in which the above acrylic fiber treatment agent is attached to the raw acrylic fiber of the acrylic fiber for carbon fiber production, and flameproofing in an oxidizing atmosphere at 200 to 300 ° C. It includes a flameproofing treatment step that converts to a fiber, and a carbonization treatment step of carbonizing the flameproofing fiber in an inert atmosphere at 300 to 2000 ° C.

The acrylic fiber treatment agent of the present invention can achieve both the bundledness of fiber bundles, prevention of fusion between fibers, and stable operability in the production of carbon fiber by performing a treatment of attaching the acrylic fiber treatment agent to a precursor in advance.
If the acrylic fiber for carbon fiber production of the present invention is used, it is possible to achieve both the bundleability of the fiber bundle, the prevention of fusion between fibers, and stable operability in the production of carbon fiber. In addition, according to the method for producing carbon fiber of the present invention, it is possible to achieve both the bundleability of the fiber bundle, the prevention of fusion between fibers, and stable operability in the production of carbon fiber, and it is possible to produce a high-quality carbon fiber. .

  The acrylic fiber treatment agent of the present invention is a treatment agent for the purpose of imparting to acrylic fibers (carbon fiber precursors) used in carbon fiber production, and is a specific compound (A) and a specific polyether compound (B ) As a main component. Details will be described below.

(Compound (A))
The compound (A) used in the acrylic fiber treating agent of the present invention is represented by the above general formula (1), and has a structure in which alkylene oxide is added to both ends of a central portion composed of a bisphenol type skeleton. is there. As described above, by using the compound (A) together with the polyether compound (B) described later, it is possible to achieve both the bundledness of the fiber bundle, the prevention of fusion between fibers, and the stable operability in the production of carbon fiber. . Furthermore, since the compound (A) has water solubility, it can be mixed with water without using a nonionic surfactant as an emulsifier. As a result, there is a problem due to the heavy use of emulsifiers that the fiber bundles are not sufficiently converged at the time of winding and unwinding in the precursor yarn production process, and at the entrance and exit of the flameproofing furnace in the flame resistance process. Can be prevented.

In the general formula (1), R ¹ and R ² are each independently a hydrogen atom or an alkyl group. 1-2 are preferable and, as for carbon number of an alkyl group, 1 is more preferable. AO is an oxyalkylene group having 2 to 4 carbon atoms, preferably an oxyalkylene group having 2 to 3 carbon atoms (oxyethylene group, oxypropylene group), and more preferably an oxyethylene group having 2 carbon atoms. m and n are each independently a number of 1 or more, preferably 4 to 20, more preferably 4 to 15, and still more preferably 4 to 10. Furthermore, it is preferable that m and n are numbers satisfying m + n = 8 to 50 in order to further exhibit the effects of the present invention. m + n is preferably 8 to 40, more preferably 8 to 30, further preferably 8 to 20, and particularly preferably 10 to 20.

  In the compound (A), the addition amount of alkylene oxide added to both ends of the central portion composed of the bisphenol type skeleton does not need to be the same on the left and right of the central portion, but the compound (A) In general, since the alkylene oxide is obtained by adding an alkylene oxide to a bisphenol compound, the amount of alkylene oxide added to both ends of the central portion composed of a bisphenol type skeleton is determined at the left and right of the central portion. In many cases, the added amount is not so different.

[Polyether compound (B)]
The compound (B) used for the acrylic fiber treating agent of the present invention is a polyether compound having a weight average molecular weight of 8000 to 25000. As described above, by using the polyether compound (B) in combination with the compound (A), it is possible to achieve both fiber bundle convergence, prevention of fusion between fibers, and stable operability in the production of carbon fibers. Furthermore, since the polyether compound (B) has water solubility, it can be mixed with water without using a nonionic surfactant as an emulsifier. As a result, there is a problem due to the heavy use of emulsifiers that the fiber bundles are not sufficiently converged at the time of winding and unwinding in the precursor yarn production process, and at the entrance and exit of the flameproofing furnace in the flame resistance process. Can be prevented.

  The polyether compound (B) is a polyalkylene glycol obtained by addition polymerization of alkylene oxide (AO) such as ethylene oxide (EO), propylene oxide (PO), butylene oxide (BO), and among them, propylene oxide (PO) A polyalkylene glycol copolymer obtained by addition polymerization of ethylene oxide (EO) is preferred. The polyether compound (B) may be used alone or in combination of two or more. The polyalkylene glycol copolymer is preferably a random or block copolymer of PO and EO. One end or both ends of the polyalkylene glycol copolymer may be blocked with an ether bond or an ester bond with a monovalent or higher alcohol or basic acid. Such a polyalkylene glycol copolymer can be obtained by copolymerizing PO, EO or the like by a known method.

  The PO / EO molar ratio of the polyether compound (B) is preferably 20/80 to 50/50, more preferably 20/80 to 40/60. The weight average molecular weight of the polyether compound (B) is preferably 10000 to 20000, more preferably 11000 to 19000, and still more preferably 12000 to 18000. In addition, the weight average molecular weight as used in the field of this invention means the value converted into polystyrene by measuring with the gel permeation chromatograph (GPC) measuring method on the following measurement conditions.

(GPC measurement conditions)
Device: Device name “HPLC LC-6A SYSTEM” (manufactured by SHIMAZU)
Column: “KF-800P (10 mm × 4.6 mmφ)”, “KF-804 (300 mm × 8 mmφ)”, “KF-802.5 (300 mm × 8 mmφ)”, “KF-801 (300 mm × 8 mmφ)” ( (SHOEX manufactured by the above)
Mobile phase: Tetrahydrofuran (THF)
Flow rate: 1.0 ml / min
Sample volume: 100 μl (100-fold dilution)
Column temperature: 50 ° C
Calibration curve creation reference material: polystyrene (PSt)

[Nonionic surfactant (C)]
The acrylic fiber treatment agent of the present invention may further contain a nonionic surfactant (C) represented by the above general formula (2) that can impart uniform adhesion to a fiber bundle in carbon fiber production. preferable.
Examples of the nonionic surfactant (C) include polyoxyalkylene alkyl ethers, polyoxyalkylene alkyl phenyl ethers, polyoxyalkylene glycol fatty acid esters, polyoxyethylene polyoxypropylene block polymers, which satisfy the general formula (2). Can be mentioned.
In formula (2), R ³ is a hydrocarbon group having 8 to 20 carbon atoms. Examples of the hydrocarbon group include an alkyl group, an alkenyl group, an aryl group, and an aralkyl group, and an alkyl group and an alkenyl group are preferable. As carbon number of a hydrocarbon group, 10-18 are preferable and 12-18 are more preferable.
“—X—” is “—O—”, “—COO—” or “—CONH—”, preferably “—O—” or “—COO—”, more preferably “—O—”.
EO is an oxyethylene group and PO is an oxypropylene group. a and b represent the average number of moles added. a is 3-20, 5-18 are preferable and 7-12 are more preferable. b is 0 to 6, preferably 0 to 3, and more preferably 0. The addition form of the EO group and the PO group may be block or random.
R ⁴ is a hydrogen atom or a hydrocarbon group having 1 to 6 carbon atoms. Examples of the hydrocarbon group include an alkyl group and an alkenyl group. R ⁴ is preferably a hydrogen atom or a hydrocarbon group having 1 to 3 carbon atoms, and more preferably a hydrogen atom.

[Modified silicone (D) having a modifying group containing a nitrogen atom]
The acrylic fiber treatment agent of the present invention preferably further contains a modified silicone (D) having a modifying group containing a nitrogen atom from the viewpoint of preventing fusion between fibers in carbon fiber production. Since the acrylic fiber treating agent of the present invention contains the total of the above-mentioned compound (A) and polyether compound (B) as the main component, the modified silicone (D) is not used as the main component, and in carbon fiber production. It is possible to achieve both bundleability of the fiber bundle, prevention of fusion between fibers, and stable operability.

  If the modified silicone (D) is a modified group containing a nitrogen atom, the type of the modified group is not particularly limited. Examples of the modifying group containing a nitrogen atom include a modifying group containing an amino bond or an imino bond (ie, an amino group), a modifying group containing an amide bond (ie, an amide group), and the like. A modified group having a plurality of different bonds may be used. The modifying group containing a nitrogen atom may be bonded to the side chain of silicone as the main chain, may be bonded to the terminal, or may be bonded to both. Moreover, you may have a polyoxyalkylene group (For example, a polyoxyethylene group, a polyoxypropylene group, a polyoxybutylene group etc.) in the molecule | numerator.

  Examples of the modified silicone (D) having a modifying group containing a nitrogen atom include amino-modified silicone, amino polyether-modified silicone, amide-modified silicone, amide polyether-modified silicone, and the like. Alternatively, a plurality of modified silicones may be used in combination.

  Further, the content of nitrogen atom in the modified silicone (D) is preferably 0.35 to 3.2% by weight, more preferably 0.37 to 2.2% by weight, and 0.40 to 1.3% by weight. Further preferred. When the content of nitrogen atoms is lower than 0.35% by weight, the emulsion stability of the emulsion may deteriorate when aqueous emulsification is performed. On the other hand, when the content of nitrogen atoms is higher than 3.2% by weight, the adhesiveness of the modified silicone (D) increases due to thermal crosslinking, which causes gum up.

  Of these modified silicones (D), amino-modified silicones are preferred because they are excellent in emulsion stability when water-based emulsified and have excellent effects when used in combination with compound (A).

  When the modified silicone (D) is an amino-modified silicone, the structure of the amino-modified silicone is not particularly limited. That is, the amino group that is a modifying group may be bonded to the side chain of silicone that is the main chain, may be bonded to the terminal, or may be bonded to both. The amino group may be a monoamine type or a polyamine type, and both may be present in one molecule.

The amino group (NH ₂ ) content in the amino-modified silicone (hereinafter referred to as “amino weight%”) is preferably 0.4 to 3.7% by weight, more preferably 0.42 to 2.5% by weight, 0.46 to 1.5% by weight is more preferable. When amino weight% is lower than 0.4 weight%, the emulsion stability of the emulsion may deteriorate when aqueous emulsification is performed. On the other hand, when the content is higher than 3.7% by weight, the tackiness of the amino-modified silicone becomes high due to thermal crosslinking, which causes gum-up.

The viscosity of the amino-modified silicone at 25 ° C. is not particularly limited, but if the viscosity is too low, the treatment agent is likely to scatter, and the emulsion stability of the emulsion deteriorates when emulsified with water, and the treatment agent is converted into fibers. It becomes impossible to apply uniformly. As a result, fiber fusion may not be prevented. On the other hand, if the viscosity is too high, gum-up due to adhesiveness may be a problem. From the standpoint of preventing these problems, the viscosity at 25 ° C. of an amino-modified silicone is preferably 50~15,000mm ² / s, more preferably 500~10,000mm ² / s, 1,000~5,000mm ² / s is more preferable.

[Surfactant]
The acrylic fiber treatment agent of the present invention may contain a surfactant as long as the effects of the present invention are not impaired. Surfactants are used as emulsifiers, antistatic agents and the like. The surfactant is not particularly limited, and is a nonionic surfactant (excluding the nonionic surfactant (C)), anionic surfactant, cationic surfactant, and amphoteric surfactant. Therefore, known ones can be appropriately selected and used. Surfactant may use together 1 type (s) or 2 or more types.

  Examples of the nonionic surfactant include polyoxyalkylene linear alkyl ethers such as polyoxyethylene hexyl ether, polyoxyethylene octyl ether, polyoxyethylene decyl ether, polyoxyethylene lauryl ether, and polyoxyethylene cetyl ether; Polyoxyalkylene branched primary alkyl ethers such as polyoxyethylene 2-ethylhexyl ether, polyoxyethylene isocetyl ether, polyoxyethylene isostearyl ether; polyoxyethylene 1-hexyl hexyl ether, polyoxyethylene 1-octyl hexyl ether Polyoxyethylene 1-hexyl octyl ether, polyoxyethylene 1-pentyl heptyl ether, polyoxyethylene 1-heptylpentyl ether Polyoxyalkylene branched secondary alkyl ethers such as ter; polyoxyalkylene alkenyl ethers such as polyoxyethylene oleyl ether; polyoxys such as polyoxyethylene octyl phenyl ether, polyoxyethylene nonyl phenyl ether, polyoxyethylene dodecyl phenyl ether Alkylene alkyl phenyl ether; polyoxyethylene tristyryl phenyl ether, polyoxyethylene distyryl phenyl ether, polyoxyethylene styryl phenyl ether, polyoxyethylene tribenzyl phenyl ether, polyoxyethylene dibenzyl phenyl ether, polyoxyethylene benzyl phenyl ether Such as polyoxyalkylene alkyl aryl phenyl ether; Laurate, polyoxyethylene monooleate, polyoxyethylene monostearate, polyoxyethylene monomyristate, polyoxyethylene dilaurate, polyoxyethylene dioleate, polyoxyethylene dimyristate, polyoxyethylene distearate, etc. Polyoxyalkylene fatty acid esters; sorbitan esters such as sorbitan monopalmitate and sorbitan monooleate; polyoxyalkylene sorbitan fatty acid esters such as polyoxyethylene sorbitan monostearate and polyoxyethylene sorbitan monooleate; glycerin monostearate and glycerin monolaur Glycerin fatty acid ester such as rate and glycerin monopalmitate; Polyoxyalkylene sorbitol fatty acid ester; Sucrose fat Acid ester; polyoxyalkylene castor oil ether such as polyoxyethylene castor oil ether; polyoxyalkylene hardened castor oil ether such as polyoxyethylene hydrogenated castor oil ether; polyoxyalkylene alkyl such as polyoxyethylene lauryl amino ether and polyoxyethylene stearyl amino ether Amino ether; oxyethylene-oxypropylene block or random copolymer; oxyethylene-oxypropylene block or random copolymer terminal alkyl etherified product; oxyethylene-oxypropylene block or random copolymer terminal sucrose etherified product; Polyoxyalkylene alkylamides such as polyoxyethylene lauryl amide and polyoxyethylene stearyl amide; Can. In addition, the nonionic surfactant illustrated here means what remove | excluding the nonionic surfactant (C) shown by the said General formula (2). Moreover, a nonionic surfactant remove | excludes a polyether compound (B). The weight average molecular weight of the nonionic surfactant is preferably 2000 or less, more preferably 200 to 1800, more preferably 300 to 1500, and still more preferably 500 to 1000.

  Among these nonionic surfactants, polyoxyalkylene branched primary alkyl ethers, polyoxyalkylene branched secondary alkyl ethers, polyoxyalkylene alkenyl ethers are preferred because they are particularly excellent in aqueous emulsifying power of esters and silicone compounds. , Polyoxyalkylene alkyl phenyl ether, polyoxyalkylene fatty acid ester, oxyethylene-oxypropylene block copolymer, terminal alkyl ether compound of oxyethylene-oxypropylene block copolymer, and polyoxyalkylene alkylamide are preferred, and further a firing step The oxyethylene-oxypropylene block or the random copolymer, the oxyethylene-oxypropylene block, because it is difficult to tar the fiber and damage the fiber. Terminal alkyl ethers of copolymers, polyoxyalkylene alkylamide is more preferable.

  The polyoxyalkylene alkylamide is a compound obtained by adding polyoxyalkylene to an acid amide that is a condensate of a carboxylic acid and an amine compound. Examples of carboxylic acids include formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, enanthic acid, caprylic acid, pelargonic acid, capric acid, lauric acid, myristic acid, palmitic acid, margaric acid, stearic acid, and the like. Can be mentioned. Examples of amine compounds include alkanolamines such as monomethanolamine, dimethanolamine, monoethanolamine, diethanolamine, monopropanolamine, dipropanolamine, and monoisopropanolamine; polyamines such as diethylenetriamine and tetraethylenepentamine. Can do. Examples of the alkylene oxide include ethylene oxide (EO), propylene oxide (PO), butylene oxide (BO), and the like. Examples of the polyoxyalkylene alkylamide include an alkylene oxide adduct of carboxylic acid monoethanolamide, an alkylene oxide adduct of carboxylic acid diethanolamide, and the like. These polyoxyalkylene alkylamides can be used alone or in combination of two or more. Among these polyoxyalkylene alkyl amides, polyoxyethylene lauryl amide and polyoxyethylene stearyl amide are preferable because they are particularly excellent in aqueous emulsifying power of esters and silicone compounds.

  Examples of the anionic surfactant include fatty acids (salts) such as oleic acid, palmitic acid, sodium oleate, potassium palmitate, triethanolamine oleate; hydroxyacetic acid, potassium potassium hydroxyacetate, lactic acid, lactic acid Hydroxyl group-containing carboxylic acid (salt) such as potassium salt; polyoxyalkylene alkyl ether acetic acid (salt) such as polyoxyethylene tridecyl ether acetic acid (sodium salt); and many carboxyl groups such as potassium trimellitic acid and potassium pyromellitic acid Substituted aromatic compound salts; alkylbenzene sulfonic acid (salt) such as dodecylbenzene sulfonic acid (sodium salt); polyoxyalkylene alkyl ether sulfonic acid (salt) such as polyoxyethylene 2-ethylhexyl ether sulfonic acid (potassium salt); Higher fatty acid amide sulfonic acid (salt) such as theauroylmethyl taurine (sodium), lauroyl methyl taurine (sodium), myristoyl methyl taurine (sodium), palmitoyl methyl taurine (sodium); N-acyl such as lauroyl sarcosine acid (sodium) Sarcosine acid (salt); alkyl phosphonic acid (salt) such as octyl phosphonate (potassium salt); aromatic phosphonic acid (salt) such as phenyl phosphonate (potassium salt); 2-ethylhexyl phosphonate mono 2-ethylhexyl ester (potassium salt) Alkylphosphonic acid esters (salts) such as alkylphosphonic acid; nitrogen-containing alkylphosphonic acid (salt) such as aminoethylphosphonic acid (diethanolamine salt); alkylsulfuric acid such as 2-ethylhexyl sulfate (sodium salt) Esters (salts); polyoxyalkylene sulfate esters (salts) such as polyoxyethylene 2-ethylhexyl ether sulfate (sodium salt); long-chain sulfosuccinates such as sodium di-2-ethylhexyl sulfosuccinate and sodium dioctyl sulfosuccinate; N -Long-chain N-acyl glutamates such as monosodium lauroyl glutamate and disodium N-stearoyl-L-glutamate;

  Examples of the cationic surfactant include lauryl trimethyl ammonium chloride, myristyl trimethyl ammonium chloride, palmityl trimethyl ammonium chloride, stearyl trimethyl ammonium chloride, oleyl trimethyl ammonium chloride, cetyl trimethyl ammonium chloride, behenyl trimethyl ammonium chloride, coconut oil alkyl trimethyl. Ammonium chloride, tallow alkyltrimethylammonium chloride, stearyltrimethylammonium bromide, coconut oil alkyltrimethylammonium bromide, cetyltrimethylammonium methosulfate, oleyldimethylethylammonium ethosulphate, dioctyldimethylammonium chloride, dill Alkyl quaternary ammonium salts such as ril dimethyl ammonium chloride, distearyl dimethyl ammonium chloride, octadecyl diethyl methyl ammonium sulfate; (polyoxyethylene) lauryl amino ether lactate, stearyl amino ether lactate, di (polyoxyethylene) lauryl Methylaminoether dimethyl phosphate, di (polyoxyethylene) laurylethylammonium ethosulphate, di (polyoxyethylene) -cured tallow alkylethylamine ethosulphate, di (polyoxyethylene) laurylmethylammonium dimethylphosphate, di (polyoxyethylene) stearyl (Polyoxyalkylene) alkylamino ether salts such as amine lactate; N- (2-hydroxyethyl)- , N-dimethyl-N-stearoylamidopropylammonium nitrate, lanolin fatty acid amidopropylethyldimethylammonium ethosulphate, acylamidoalkyl quaternary ammonium salts such as lauroylamidoethylmethyldiethylammonium methosulfate; dipalmityl polyethenoxyethyl Alkylethenoxy quaternary ammonium salts such as ammonium chloride and distearyl polyethenoxymethylammonium chloride; alkylisoquinolinium salts such as laurylisoquinolinium chloride; lauryldimethylbenzylammonium chloride, stearyldimethylbenzylammonium chloride and the like Benzalkonium salt; benzyldimethyl {2- [2- (p-1,1,3,3-tetramethylbutylphenol) Oxy) ethoxy] ethyl} ammonium chloride and other benzethonium salts; cetylpyridinium chloride and other pyridinium salts; oleyl hydroxyethyl imidazolinium etosulphate, imidazolinium salts such as lauryl hydroxyethyl imidazolinium etosulphate; N-cocoyl arginine ethyl Acyl basic amino acid alkyl ester salts such as ester pyrrolidone carboxylate and N-lauroyllysine ethyl ethyl ester chloride; Primary amine salts such as laurylamine chloride, stearylamine bromide, hardened beef tallow alkylamine chloride, rosinamine acetate; cetyl Methylamine sulfate, laurylmethylamine chloride, dilaurylamine acetate, stearylethylamine bromide, lauric Secondary amine salts such as rupropylamine acetate, dioctylamine chloride, octadecylethylamine hydroxide; dilaurylmethylamine sulfate, lauryldiethylamine chloride, laurylethylmethylamine bromide, diethanol stearylamide ethylamine trihydroxyethyl phosphate salt, stearylamide Examples include tertiary amine salts such as ethyl ethanolamine urea polycondensate acetate; fatty acid amidoguanidinium salts; alkyltrialkylene glycol ammonium salts such as lauryl triethylene glycol ammonium hydroxide.

  Examples of amphoteric surfactants include 2-undecyl-N, N- (hydroxyethylcarboxymethyl) -2-imidazoline sodium, 2-cocoyl-2-imidazolinium hydroxide-1-carboxyethyloxy disodium salt, and the like. Imidazoline-based amphoteric surfactants; 2-heptadecyl-N-carboxymethyl-N-hydroxyethylimidazolium betaine, lauryldimethylaminoacetic acid betaine, alkylbetaines, amide betaines, sulfobetaine, and other betaine-based amphoteric surfactants; N- Amino acid type amphoteric surfactants such as lauryl glycine, N-lauryl β-alanine, N-stearyl β-alanine and the like can be mentioned.

  Among these surfactants, nonionic surfactants are preferred because they are excellent in stability over time and in emulsifying power. Compared with nonionic surfactants, ionic surfactants have the advantage of excellent antistatic properties that can suppress fiber bundle fluctuations due to the generation of static electricity, so they should be used in combination with nonionic surfactants. Is preferred. Examples of the ionic surfactant include the above-mentioned anionic surfactants, cationic surfactants, and amphoteric surfactants. Among these, cationic surfactants are preferable, and among the cationic surfactants. Alkyl quaternary ammonium salts, (polyoxyalkylene) alkyl amino ether salts, acylaminoalkyl quaternary ammonium salts, alkylethenoxy quaternary ammonium salts, primary amine salts, secondary amine salts, tertiary More preferred are secondary amine salts and the like.

[Other ingredients]
The acrylic fiber treatment agent of the present invention may contain other components other than the above-described components as long as the effects of the present invention are not impaired. Other components include acid phosphate esters, phenolic, amine-based, sulfur-based, phosphorus-based and quinone-based antioxidants; sulfates of higher alcohols and higher alcohol ethers, sulfonates, higher alcohols and higher alcohols Antistatic agents such as phosphate salts of alcohol ethers, quaternary ammonium salt type cationic surfactants, amine salt type cationic surfactants; smoothing agents such as alkyl esters of higher alcohols, higher alcohol ethers, waxes, etc. Antibacterial agents; antiseptics; rust preventives; and hygroscopic agents.

The antioxidant is a component that effectively suppresses thermal decomposition of the acrylic fiber treatment agent by heating in the flameproofing treatment step and enhances the effect of preventing fusion between fibers.
Although there is no limitation in particular as antioxidant, From a viewpoint of baking furnace contamination prevention, an organic antioxidant and acidic phosphate ester are preferable, and acidic phosphate ester is further more preferable. Examples of organic antioxidants include 4,4′-butylidenebis (3-methyl-6-tert-butylphenol, trioctadecyl phosphite, N, N′-diphenyl-p-phenylenediamine, triethylene glycol bis [3- (3-t-butyl-4-hydroxy-5-methylphenyl) propionate], dioleyl-thiodipropionate, etc. These organic antioxidants may be used alone or in combination of two or more. Good.
As acidic phosphate ester, the acidic phosphate ester described in the claim of international publication WO2013 / 129115 can be mentioned, for example. Moreover, acidic phosphate ester can be manufactured by a well-known method, as described in the 0036 paragraph of international publication WO2013 / 129115. For example, an inorganic phosphoric acid such as anhydrous phosphoric acid P ₂ O ₅ , a compound having an alcoholic hydroxyl group in the molecule such as an alcohol or a polyoxyalkylene-added alkyl ether (hereinafter sometimes simply referred to as a raw material alcohol), an arbitrary It is obtained by reacting at a molar ratio of The obtained acidic phosphoric acid ester contains acidic polyphosphate esters (forming salts) such as by-produced acidic pyrophosphate esters (unneutralized pyrophosphate esters not forming a salt) and acidic triphosphate esters. Non-neutralized polyphosphate ester) may be contained.

  Moreover, the acrylic fiber treating agent of the present invention may contain a silicone component other than the modified silicone (D) having a modifying group containing a nitrogen atom as long as the effects of the present invention are not impaired. Specifically, dimethyl silicone, epoxy-modified silicone, alkylene oxide-modified silicone (polyether-modified silicone), epoxy polyether-modified silicone (see, for example, Japanese Patent No. 4616934), carboxy-modified silicone, carbinol-modified silicone, alkyl-modified silicone, Examples include phenol-modified silicone, methacrylate-modified silicone, alkoxy-modified silicone, and fluorine-modified silicone.

  Moreover, the acrylic fiber treatment agent of this invention may contain an ester compound in the range which does not inhibit the effect of this invention. Examples of ester compounds include ester compounds having 3 or more ester groups in the molecule described in republished WO 2007/066517, and sulfur-containing esters described in international application PCT / JP2013 / 75081. A compound etc. can be mentioned.

[Acrylic fiber treatment agent]
The acrylic fiber treating agent of the present invention essentially contains the compound (A) represented by the general formula (1) and the polyether compound (B) having a weight average molecular weight of 8000 to 25000. The total weight ratio of the compound (A) and the polyether compound (B) in the nonvolatile content of the treatment agent is preferably 50 to 99% by weight, more preferably 55 to 95% by weight, and 60 to 90% by weight. % Is more preferable, and 65 to 80% by weight is particularly preferable. The non-volatile content in the present invention refers to an absolutely dry component when the treatment agent is heat treated at 105 ° C. to remove the solvent and the like and reach a constant weight.

  Weight ratio (A / B) of the compound (A) and the polyether compound (B) from the viewpoint that both the bundleability of the fiber bundle in carbon fiber production, the prevention of fusion between fibers, and stable operability can be achieved. Is preferably 90/10 to 20/80, more preferably 75/25 to 35/65, and still more preferably 65/35 to 45/55.

  When the acrylic fiber treatment agent of the present invention contains a nonionic surfactant (C), the weight ratio of the nonionic surfactant (C) in the nonvolatile content of the treatment agent is 0.5 to 15% by weight. 1 to 10% by weight is more preferable, 1 to 8% by weight is further preferable, and 3 to 5% by weight is particularly preferable.

  When the acrylic fiber treatment agent of the present invention contains the modified silicone (D), the weight percentage of the modified silicone (D) in the nonvolatile content of the treatment agent is more preferably 5 to 40% by weight, and 10 to 30% by weight. Further preferred is 15 to 25% by weight.

  The acrylic fiber treatment agent of the present invention can reduce the amount of nonionic surfactant used as an emulsifier. As a result, the total amount of nonionic surfactant can be reduced. Specifically, the weight ratio of the nonionic surfactant (total amount) in the nonvolatile content of the treatment agent can be 20% by weight or less, preferably 15% by weight or less, and more preferably 10% by weight or less. When the weight ratio exceeds 20% by weight, fiber bundles may be deteriorated in the precursor yarn-making process and the flame-proofing process due to the influence of a large amount of nonionic surfactant. When the acrylic fiber treatment agent of the present invention contains a nonionic surfactant (C), the weight ratio of the nonionic surfactant (total amount) in the nonvolatile content of the treatment agent is preferably 1 to 20% by weight. 2 to 15% by weight is more preferable, and 3 to 10% by weight is more preferable.

The acrylic fiber treatment agent of the present invention comprises a compound (A), a polyether compound (B), a nonionic surfactant (C), and a modified silicone (D), if necessary, dissolved, solubilized, emulsified or emulsified in water. A dispersed state is preferable.
There is no particular limitation on the weight ratio of water and the weight ratio of non-volatile content in the entire acrylic fiber treatment agent. For example, what is necessary is just to determine suitably in consideration of the transport cost at the time of transporting the acrylic fiber processing agent of this invention, the handleability etc. resulting from emulsion viscosity, etc. The weight ratio of water in the entire acrylic fiber treating agent is preferably 0.1 to 99.9% by weight, more preferably 10 to 99.5% by weight, and particularly preferably 50 to 99% by weight. The weight ratio (concentration) of the nonvolatile component in the entire acrylic fiber treatment agent is preferably 0.01 to 99.9% by weight, more preferably 0.5 to 90% by weight, and particularly preferably 1 to 50% by weight.

  From the viewpoint of heat resistance in the flameproofing treatment process and the effect of preventing fiber-fiber fusion, the weight reduction rate after heat treatment at 250 ° C. in air for 1 hour in the acrylic fiber treatment agent of the present invention is Is less than 30% by weight, more preferably less than 25%. When the weight reduction rate is 40% or more, the treatment agent film remaining on the fiber in the flameproofing treatment step decreases, and the effect of preventing the fusion between the fibers and the fibers may not be sufficiently obtained.

  The acrylic fiber treatment agent of the present invention can be produced by mixing the components described above. The method for emulsifying and dispersing the components described above is not particularly limited, and a known method can be employed. As such a method, for example, each component constituting the acrylic fiber treatment agent is put into warm water under stirring and emulsified and dispersed, or each component constituting the acrylic fiber treatment agent is mixed, and then homogenizer, homogenizer is mixed. Examples include a method of phase inversion emulsification by gradually adding water while applying mechanical shearing force using a mixer, a ball mill, or the like.

  The acrylic fiber treatment agent of the present invention can be suitably used as a treatment agent (precursor treatment agent) for acrylic fibers (precursor) for producing carbon fibers. You may use as spinning oil agent of acrylic fibers other than a precursor.

  The viscosity at 50 ° C. of the nonvolatile content of the acrylic fiber treatment agent of the present invention is preferably 350 to 25000 mPa · s, and preferably 1000 to 20000 mPa · s, from the viewpoint of imparting good fiber bundle convergence in the precursor yarn-making process and flameproofing process. s is more preferable, and 1500 to 15000 mPa · s is more preferable. When the viscosity is less than 350 mPa · s, fiber bundles may be deteriorated in the precursor yarn-making process or the flame-proofing process. Further, if the viscosity exceeds 25000 mPa · s, the treatment agent viscosity becomes too high and the handling property of the treatment agent deteriorates even if good fiber bundle convergence in the precursor yarn forming process and the flameproofing process can be imparted. There is a case. In addition, the measuring method of this viscosity is based on the method described in the Example.

[Acrylic fiber for producing carbon fiber, method for producing the same, and method for producing carbon fiber]
The acrylic fiber for carbon fiber production (precursor) of the present invention is produced by attaching the above-mentioned acrylic fiber treatment agent to the precursor acrylic fiber of the precursor. The method for producing a precursor according to the present invention includes a yarn production step in which the acrylic fiber treatment agent is attached to the raw material acrylic fiber of the precursor to produce a yarn.
The carbon fiber production method of the present invention includes a spinning process in which the above acrylic fiber treatment agent is attached to the precursor acrylic fiber to produce the precursor, and the precursor produced in the spinning process is oxidized at 200 to 300 ° C. A flameproofing process for converting to a flameproofed fiber in a neutral atmosphere, and a carbonization process for carbonizing the flameproofed fiber in an inert atmosphere at 300 to 2000 ° C.

The yarn making process is a process of making a precursor by attaching an acrylic fiber treatment agent to the precursor raw acrylic fiber, and includes an adhesion treatment process and a stretching process.
The adhesion treatment process is a process of adhering the acrylic fiber treatment agent after spinning the precursor raw acrylic fiber. That is, the acrylic fiber treatment agent is adhered to the precursor raw acrylic fiber in the adhesion treatment step. The precursor raw acrylic fiber is stretched immediately after spinning, and the high-strength stretching after the adhesion treatment step is particularly called a “stretching step”. The stretching process may be a wet heat stretching method using high temperature steam or a dry heat stretching method using a hot roller.

  A precursor is comprised from the acrylic fiber which has as a main component the polyacrylonitrile obtained by copolymerizing at least 95 mol% or more of acrylonitrile and 5 mol% or less of a flame-resistant acceleration | stimulation component. As the flame resistance promoting component, a vinyl group-containing compound having copolymerizability with acrylonitrile can be suitably used. Although there is no limitation in particular about the single fiber fineness of a precursor, from the balance of a performance and manufacturing cost, Preferably it is 0.1-2.0 dTex. Further, the number of single fibers constituting the precursor fiber bundle is not particularly limited, but is preferably 1,000 to 96,000 from the balance between performance and production cost.

  The acrylic fiber treatment agent may be attached to the precursor raw acrylic fiber at any stage of the yarn production process, but is preferably attached once before the drawing process. It may be attached at any stage before the stretching process, for example, immediately after spinning. Further, it may be reattached at any stage after the stretching process, for example, it may be reattached immediately after the stretching process, it may be reattached at the winding stage, or it may be reattached immediately before the flameproofing process. You may let them. As for the attachment method, it may be attached using a roller or the like, or may be attached by a dipping method, a spray method or the like.

  In the adhesion treatment process, the application rate of the acrylic fiber treatment agent obtains the effect of preventing fiber-to-fiber sticking and the prevention of fusion, and prevents the deterioration of the quality of the carbon fiber due to the tar product of the treatment agent in the carbonization treatment process. From the balance with the content of the precursor, it is preferably 0.1 to 2% by weight, more preferably 0.3 to 1.5% by weight, based on the weight of the precursor. When the application rate of the acrylic fiber treatment agent is less than 0.1% by weight, sticking and fusion between single fibers cannot be sufficiently prevented, and the strength of the obtained carbon fibers may be lowered. On the other hand, when the application rate of the acrylic fiber treatment agent is more than 2% by weight, the acrylic fiber treatment agent covers more than necessary between the single fibers, so that the supply of oxygen to the fibers is hindered in the flameproofing treatment step, and thus obtained. The strength of the carbon fiber may decrease. In addition, the provision rate of an acrylic fiber processing agent here is defined with the percentage of the non volatile matter weight to which the acrylic fiber processing agent adhered with respect to the precursor weight.

  The flameproofing treatment step is a step of converting the precursor with the acrylic fiber treating agent attached thereto into flameproofing fibers in an oxidizing atmosphere at 200 to 300 ° C. The oxidizing atmosphere is usually an air atmosphere. The temperature of the oxidizing atmosphere is preferably 230 to 280 ° C. In the flameproofing treatment step, the acrylic fiber after the adhesion treatment is applied for 20 to 100 minutes (preferably 30) while applying a tension ratio of 0.90 to 1.10 (preferably 0.95 to 1.05). Heat treatment is performed for ˜60 minutes. In this flameproofing treatment, a flameproof fiber having a flameproof structure is produced through intramolecular cyclization and oxygen addition to the ring.

  The carbonization treatment step is a step of carbonizing the flameproof fiber in an inert atmosphere of 300 to 2000 ° C. In the carbonization treatment step, first, in a firing furnace having a temperature gradient from 300 ° C. to 800 ° C. in an inert atmosphere such as nitrogen or argon, a tension ratio of 0.95 to 1.15 is applied to the flameproof fiber. It is preferable to carry out a pre-carbonization treatment step (first carbonization treatment step) by applying heat treatment for several minutes while applying. Thereafter, in order to further promote carbonization and advance graphitization, a tension ratio of 0.95 to 1.05 is applied to the first carbonization treatment step in an inert atmosphere such as nitrogen or argon. While being applied, heat treatment is performed for several minutes to perform the second carbonization treatment step, and the flame resistant fiber is carbonized. About control of the heat processing temperature in a 2nd carbonization process process, it is good to make maximum temperature into 1000 degreeC or more (preferably 1000-2000 degreeC), applying a temperature gradient. This maximum temperature is appropriately selected and determined according to the required characteristics (tensile strength, elastic modulus, etc.) of the desired carbon fiber.

  In the carbon fiber manufacturing method of the present invention, when a carbon fiber having a higher elastic modulus is desired, the graphitization treatment step can be performed subsequent to the carbonization treatment step. The graphitization treatment step is usually performed at a temperature of 2000 to 3000 ° C. while applying tension to the fiber obtained in the carbonization treatment step in an inert atmosphere such as nitrogen or argon.

  The carbon fiber thus obtained can be subjected to a surface treatment for increasing the adhesive strength with the matrix resin when made into a composite material, depending on the purpose. As the surface treatment method, gas phase or liquid phase treatment can be adopted, and from the viewpoint of productivity, liquid phase treatment with an electrolytic solution of acid, alkali or the like is preferable. Furthermore, various sizing agents having excellent compatibility with the matrix resin can be added to improve the processability and handleability of the carbon fiber.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, it is not limited to the Example described here. In addition, the percentage (%) and part shown in the following examples indicate “% by weight” and “part by weight” unless otherwise specified. Each characteristic value was measured based on the following method.

<Application rate of treatment agent>
The application rate of the acrylic fiber treating agent was calculated by an ethanol extraction method using a Soxhlet extractor. However, about the Example and modified example containing modified silicone (D), the provision rate was computed with the following method.
The precursor after application of the treatment agent was alkali-melted with potassium hydroxide / sodium butyrate, dissolved in water, and adjusted to pH 1 with hydrochloric acid. This was added with sodium sulfite and ammonium molybdate to develop a color, and colorimetric determination (wavelength 815 mμ) of silicomomolybdenum blue was performed to determine the silicon content. The application rate (% by weight) of the acrylic fiber treatment agent was calculated using the silicon content obtained here and the value of the silicon content in the treatment agent obtained in advance by the same method.

<Viscosity>
Each treatment agent was sampled on an aluminum cup having a diameter of 60 mm so that the weight of the nonvolatile component became 1 g, and treated with a hot air dryer at 105 ° C. for 3 hours to remove moisture. The obtained sample (1 g) was carried out using an ICI cone plate viscometer (manufactured by RESEACH EQUIIPMENT (LONDON) LTD.).
More specifically, the temperature of the plate is set to 50 ° C., then the sample is loaded into the sample loading port provided on the plate, and then the cone plate is lowered to the sample loading port, and then 90 seconds. Later, the motor was switched on and measurement started. The value when the numerical value was stabilized was taken as the measured value.

<Yarn operability (roller dirt)>
The degree of contamination (gum-up) of the drying roller after applying the treatment agent to 50 kg of the precursor was determined according to the following evaluation criteria.
◎: There is no roller contamination due to gum-up, and there is no problem with spinning operation ○: Little roller contamination due to gum-up and there is no problem with yarn-making operability △: Roller contamination due to gum-up is slightly inferior, x Roller contamination due to

<Fiber bundle convergence>
The degree of convergence of the fiber bundles was observed at the entrance and exit of the flameproofing furnace at the time of winding, unwinding and at the flameproofing process in the precursor yarn making process, and comprehensively judged visually by the following evaluation criteria.
(Double-circle): It is a fiber bundle of uniform thickness, and the single fiber variation is not seen at all.
○: A fiber bundle having a uniform thickness, with almost no single fiber flaking.
(Triangle | delta): Although it is a fiber bundle of uniform thickness, the loose single fiber is seen a little.
X: Many single fibers were broken and single yarn breakage was observed.

<Fused prevention>
Twenty locations were selected at random from carbon fibers, 10 mm-long short fibers were cut out therefrom, the fused state was observed, and the following evaluation criteria were used.
◎: No fusion ○: Almost no fusion △: Less fusion ×: Many fusion

<Carbon fiber strength>
Measurement was performed according to the epoxy resin impregnated strand method defined in JIS-R-7601, and the average value of 10 measurements was defined as carbon fiber strength (GPa).

(Preparation of modified silicone (D) emulsion)
The following modified silicones D1 to D4 are respectively nonionic surfactants (polyoxyethylene 7 mol addition alkyl ether (the alkyl group has 12 to 14 carbon atoms), polyoxyethylene 12 mol addition tristyrenated phenyl ether and ethylene oxide / propylene oxide. (50/50) block copolymer) is water-based emulsified, and has a non-volatile composition of the following modified silicone / non-ionic surfactant = 80/20 weight ratio modified silicone having a non-volatile content of 20% by weight. An emulsion was obtained.
D1: amino-modified silicone (viscosity at 25 ° C .: 1300 mm ² / s, amino equivalent: 2000 g / mol, modified type: diamine)
D2: amino-modified silicone (25 ° C. viscosity: 90 mm ² / s, amino equivalent: 2200 g / mol, modified type: both ends)
D3: amino-modified silicone (viscosity at 25 ° C .: 250 mm ² / s, amino equivalent: 7600 g / mol, modified type: diamine)
D4: amino-modified silicone (viscosity at 25 ° C .: 90 mm ² / s, amino equivalent: 8800 g / mol, modified type: monoamine)

(Preparation of ester compound (E) emulsion)
Each of the following ester compounds E1 and E2 is a nonionic surfactant (polyoxyethylene 7 mol addition alkyl ether (alkyl group having 12 to 14 carbon atoms), polyoxyethylene 12 mol addition tristyrenated phenyl ether and ethylene oxide / propylene. Oxide (50/50) block copolymer) and water-based emulsification, and the non-volatile composition is an ester having a non-volatile content of 20% by weight consisting of a weight ratio of the following ester compound / the nonionic surfactant = 70/30 An emulsion of the system compound was obtained.
E1: Dilauryl ester of ethylene oxide 2-mole adduct of bisphenol A E2: Triisodecyl trimellitic acid

[Examples 1 to 28, Comparative Examples 1 to 13]
The following compounds A1 to A3, polyether compounds B1 to B3, nonionic surfactants C1 to C3, aqueous emulsions of modified silicones D1 to D4 prepared above, aqueous emulsions of ester compounds E1 to E2, and water Were mixed and stirred so as to have the non-volatile composition shown in Tables 1 to 3, and acrylic fiber treatment agents having a non-volatile content in the treatment agent of 20% by weight were prepared. In addition, the numerical value of a table | surface shows the weight ratio of each component which occupies for the non volatile matter of a processing agent. For example, the numerical values of the compounds A1 to A3 in the table indicate the weight ratio of the compounds A1 to A3 in the nonvolatile content of the treatment agent. Moreover, the numerical value of "nonionic surfactant" of Tables 1-3 shows the weight ratio (weight%) of the nonionic surfactant (total amount) which occupies for a non volatile matter.
Next, the prepared treatment agent was further diluted with water to obtain treatment solutions having a nonvolatile content concentration of 3.0% by weight.
Each treatment solution was adhered to a precursor (single fiber fineness 0.8 dtex, 24,000 filaments) so as to give an application rate of 1.0% by weight, and dried at 100 to 140 ° C. to remove moisture. The precursor after the treatment liquid was attached was flameproofed for 60 minutes in a 250 ° C flameproofing furnace, and then baked in a carbonization furnace having a temperature gradient of 300 to 1400 ° C in a nitrogen atmosphere to be converted into carbon fibers. The evaluation result of each characteristic value is shown in Tables 1-3.

A1: POE (8) bisphenol A ether A2: POE (10) bisphenol A ether A3: POE (17.5) bisphenol A ether The above POE (X) bisphenol A ether is represented by R in the general formula (1) ¹ and R ² represent a hydrogen atom, m + n = X, and AO represents an oxyethylene group having 2 carbon atoms.

B1: PO / EO = 25/75 polyether (weight average molecular weight 13000): PO and EO randomly added to diethylene glycol at a weight ratio of PO / EO = 25/75, and the weight average molecular weight is 12,000. Polyether compounds.
B2: PO / EO = 25/75 polyether (weight average molecular weight 15000): PO and EO randomly added to diethylene glycol at a weight ratio of PO / EO = 25/75, and the weight average molecular weight is 15,000. Polyether compounds.
B3: PO / EO = 25/75 polyether (weight average molecular weight 18500): PO and EO randomly added to diethylene glycol at a weight ratio of PO / EO = 25/75, and the weight average molecular weight is 18500. Polyether compounds.

C1: Nonionic surfactant obtained by adding an average of 7 mol of EO to a linear primary alcohol having 12 to 14 carbon atoms C2: 7 mol of EO was added to an average of 7 mol of secondary alcohol having 12 to 14 carbon atoms Nonionic surfactant C3: Nonionic surfactant obtained by adding a block to a linear primary alcohol having 12 to 14 carbon atoms in the order of an average of 5 mol of EO, an average of 2 mol of PO, and an average of 3 mol of EO

As shown in Tables 1 to 3, it can be seen that, in any of the examples, it is possible to achieve both the bundleability of the fiber bundle, the prevention of fusion between fibers, and the stable operability in the production of carbon fibers.
On the other hand, in the comparative example, it can be seen that the bundledness of the fiber bundle, the prevention of fusion between the fibers, and the stable operability in the production of the carbon fiber are not compatible. As in Comparative Examples 1 to 3 and 8 to 10, the yarn maneuverability is relatively good, but when the bundle of fibers is deteriorated and the carbon fiber strength is inferior, or Comparative Examples 4 to 7 and 11 to 13 In addition, it can be seen that the prevention of fusion between the fibers is relatively good, but the yarn operability is deteriorated.

  The acrylic fiber treatment agent of the present invention is a treatment agent used when producing an acrylic fiber for producing carbon fibers, and is useful for producing high-quality carbon fibers. The acrylic fiber for producing carbon fiber of the present invention is treated with the treatment agent of the present invention and is useful for producing high-quality carbon fiber. High quality carbon fibers can be obtained by the carbon fiber manufacturing method of the present invention.

Claims (8)

An acrylic fiber treatment agent,
A compound (A) represented by the following general formula (1) and a polyether compound (B) having a weight average molecular weight of 8000 to 25000,
The acrylic fiber processing agent whose total weight ratio of the said compound (A) and the said polyether compound (B) to the non volatile matter of a processing agent is 50 to 99 weight%.

(In Formula (1), R ¹ and R ² are each independently a hydrogen atom or an alkyl group. AO is an oxyalkylene group having 2 to 4 carbon atoms. M and n are each independently 1 or more.)   The acrylic fiber processing agent of Claim 1 whose weight ratio (A / B) of the said compound (A) and the said polyether compound (B) is 90 / 10-20 / 80. The acrylic fiber processing agent of Claim 1 or 2 which further contains the nonionic surfactant (C) shown by following General formula (2).

(In the formula (2), R ³ is a hydrocarbon group having 8 to 20 carbon atoms. -X- is -O-, -COO- or -CONH-. EO is an oxyethylene group, and PO is an oxy group. A and b represent the average number of moles added, a is from 3 to 20, and b is from 0 to 6. The addition form of the EO group and the PO group may be block or random, R ⁴ is It is a hydrogen atom or a C1-C6 hydrocarbon group.)   The acrylic fiber processing agent of Claim 3 whose weight ratio of the said nonionic surfactant (C) to the non volatile matter of a processing agent is 0.5 to 15 weight%.   The acrylic fiber treating agent according to any one of claims 1 to 4, further comprising a modified silicone (D) having a modifying group containing a nitrogen atom.   The acrylic fiber processing agent of Claim 5 whose weight ratio of the said modified silicone (D) to the non volatile matter of a processing agent is 5 to 40 weight%.   The acrylic fiber for carbon fiber manufacture which made the acrylic fiber processing agent in any one of Claims 1-6 adhere to the raw material acrylic fiber of the acrylic fiber for carbon fiber manufacture, and produced the yarn.   A yarn-making process in which the acrylic fiber treatment agent according to any one of claims 1 to 6 is attached to a raw acrylic fiber for acrylic fiber for carbon fiber production, and a flame-resistant fiber in an oxidizing atmosphere at 200 to 300 ° C. A method for producing carbon fiber, comprising: a flameproofing treatment step for converting to a carbon dioxide, and a carbonization treatment step for carbonizing the flameproofed fiber in an inert atmosphere at 300 to 2000 ° C.