JP2002266250A - Spinning oil for carbon fiber production process - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a spinning oil which is useful for a carbon fiber production process, exhibits excellent heat resistance and excellent single fiber adhesion- preventing property and does not cause the deterioration in the performance of carbon fibers due to ash. SOLUTION: This spinning oil for the carbon fiber production process is characterized by containing one or more compounds represented by general formula (1) [X is H or a monocarboxylic acid residue; R is a 2 to 32C hydrocarbon group; A is a 2 to 10C hydrocarbon group; (m) is an integer of 1 to 100; (n) is an integer of 1 to 500; a plurality of Xs, Rs, As or (n)s may be identical or different, respectively].

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to an oil agent for a carbon fiber production process. More specifically, the present invention relates to an oil agent for a carbon fiber manufacturing process which is applied before a process for manufacturing a precursor fiber of a carbon fiber or a process for stabilizing a carbon fiber.

[0002]

2. Description of the Related Art Carbon fibers are generally used under an oxidizing atmosphere.
Since it is manufactured through a process of heating to 700 ° C. or more in an inert atmosphere after being heated to 00 ° C. to 300 ° C., it has a high degree of heat resistance and performance such that fibers are not fused even when subjected to heat treatment. Is required. Conventionally, an organopolysiloxane compound having an amino-modified group has been known as an oil agent for a carbon fiber production process exhibiting excellent heat resistance and anti-adhesion properties of a single fiber (JP-A-5-140821).
No.).

[0003]

However, in the above-mentioned organopolysiloxane compound, the processing cost of the silicon compound (ash) remaining after the firing, the damage to the inner wall of the firing furnace due to the ash, and the performance of the carbon fiber due to the remaining ash. There was a problem of reduction.

[0004]

According to the present invention, there is provided an oil agent for a carbon fiber production process, comprising one or more compounds represented by the following general formula (1): A method for treating a precursor fiber of a carbon fiber in which the oil agent is applied to the precursor fiber of the carbon fiber in an amount of 0.01 to 10% by mass on a pure basis based on the mass of the fiber after the treatment; Carbon fiber produced by the above method. Wherein X: a hydrogen atom or a monocarboxylic acid residue R: a hydrocarbon group having 2 to 32 carbon atoms A: a hydrocarbon group having 2 to 10 carbon atoms m: an integer of 1 to 100 n: 1 to 500 Integer A plurality of X, R, A, and n may be the same or different. ]

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The oil agent for a carbon fiber production process of the present invention contains a compound represented by the general formula (1) as an essential component. In the formula (1), X is a hydrogen atom or a monocarboxylic acid residue, and each X may be the same or different. X is preferably a monocarboxylic acid residue. The monocarboxylic acid residue means a residue obtained by removing OH from a monocarboxylic acid. The carbon number of the monocarboxylic acid residue is usually 2 to
32, preferably 4 to 24, more preferably 8
~ 18. When the carbon number is in this range, the smoothness as an oil agent becomes better. Examples of the monocarboxylic acid include saturated fatty acids having 2 to 32 carbon atoms (acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid,
C3 to C32 unsaturated fatty acids (acrylic acid, methacrylic acid, oleic acid, linoleic acid, linolenic acid, etc.), C6 to C32 cyclic saturated carboxylic acids (cyclohexanecarboxylic acid, cyclooctanecarboxylic acid) Acid, etc.), a cyclic unsaturated carboxylic acid having 6 to 32 carbon atoms (eg, cyclohexene carboxylic acid), and a carbon number of 7
To 32 aromatic carboxylic acids (phenylacetic acid, benzoic acid, toluic acid, etc.). Preferred among these are saturated and unsaturated fatty acids, and more preferred are lauric, palmitic, stearic and oleic acids.

R is one or more divalent hydrocarbon groups having 2 to 32 carbon atoms, and when m is 2 or more, a plurality of Rs are
They may be the same or different. R preferably has 2 to 18 carbon atoms, more preferably 2 to 10 carbon atoms, and particularly preferably 2 to 6 carbon atoms. When the carbon number of R is within these ranges, the adsorbability of the carbon fibers to the precursor fibers (acrylic fibers, rayon fibers, pitch-based fibers, etc .; hereinafter, these are abbreviated as precursors) tends to be further improved. There is. Examples of the hydrocarbon group include a linear or branched saturated hydrocarbon group having 2 to 32 carbon atoms (such as an ethylene group, a propylene group, and a butylene group);
C5-C32 saturated cyclic hydrocarbon group (cyclohexylene group, cyclooctylene group, etc.), C5-C32 unsaturated cyclic hydrocarbon group (cyclopentadienylene group, etc.)
And an aromatic hydrocarbon group having 6 to 32 carbon atoms (phenylene group, benzylene group, tolylene group, biphenylene group, naphthylene group, etc.). Of these, preferred are straight-chain saturated hydrocarbon groups and aromatic hydrocarbon groups, more preferred are ethylene groups, 1,3-propylene groups and phenylene groups, and particularly preferred are ethylene groups. is there.

A is at least one divalent hydrocarbon group having 2 to 10 carbon atoms. A preferably has 2 to 6 carbon atoms, and more preferably 2 to 4 carbon atoms. When the carbon number of A is within this range, the balance between heat resistance and smoothness is good. Specific examples of A include those having 2 to 10 carbon atoms among those described for the example of R. Of these, preferred are linear or branched saturated hydrocarbon groups, and more preferred are ethylene groups, 1,2- and 1,3-propylene groups, 1,2-, 1,3-, 2, 3-
And 1,4-butylene groups, particularly preferred are ethylene groups and 1,2-propylene groups.

M is an integer of 1 to 100;
It is preferably 0, more preferably 1 to 50, and particularly preferably 1 to 10. When m is in this range, the heat resistance becomes good.

N is an integer of 1 to 500, and 3 to 3
It is preferably 00, more preferably 5 to 200. When n is in this range, the viscosity of the oil agent is in an appropriate range, and the adhesion is good. As n decreases, dispersibility in water tends to decrease, and as n increases, thermal stability and adhesion to fibers tend to decrease.

As the compound represented by the formula (1), for example, an alkylene oxide having 2 to 10 carbon atoms is added to a polyamine or an amidated product thereof with a monocarboxylic acid, and if necessary, further esterified with a monocarboxylic acid. Compounds having the following structures: The polyamine preferably has 2 to 200 carbon atoms, more preferably has 2 to 100 carbon atoms, and particularly preferably has 2 to 32 carbon atoms. As a specific example, it has 2 to 32 carbon atoms (preferably 2 to 32 carbon atoms).
6) alkylenediamine (ethylenediamine, 1,3
-Diaminopropane, 1,4-diaminobutane, 1,5
-Diaminopentane, etc.), polyalkylenepolyamines having 4 to 32 (preferably 4 to 12) carbon atoms (such as diethylenetriamine, triethylenetetramine, and pentaethylenehexamine), and aromatic diamines having 6 to 32 carbon atoms (such as phenylenediamine) ). Of these, preferred are alkylene diamines having 2 to 6 carbon atoms, polyalkylene polyamines having 4 to 12 carbon atoms,
And phenylenediamine, and more preferred is ethylenediamine.

As an example of the above monocarboxylic acid, X
Examples of the acid forming the monocarboxylic acid residue include the compounds exemplified above. The same applies to preferred examples.

Examples of the alkylene oxide include ethylene oxide (EO), propylene oxide (PO), 1,2-, 1,3-, 2,3- and 1,4.
-Butylene oxide (BO), styrene oxide, and combinations of two or more of these (block and / or random addition). Of these, preferably E
O, PO and BO, and more preferably EO and PO.

The method for producing the compound of the formula (1) is not particularly limited. For example, 1 mol of a polyamine having two amino groups and (m-1) (0 when m = 1) imino groups After amidation by reacting about 2 moles of monocarboxylic acid with respect to the alkylene oxide (m + 1) -500
(M + 1) mol in the presence of a basic or acidic catalyst
A method in which an addition reaction is carried out at a temperature of from 150 ° C. to 150 ° C., and a reaction product is further reacted with a monocarboxylic acid to carry out esterification.

The reaction conditions for the amidation and the esterification at this time may be the methods usually used, and in any case, the reaction can be carried out under normal pressure, increased pressure or reduced pressure.
It may be performed in the presence of a catalyst. The reaction temperature is usually 70 to 25
At 0 ° C., the reaction time is usually 1 to 30 hours. Examples of the catalyst include an acid catalyst (eg, paratoluenesulfonic acid, methanesulfonic acid, sulfuric acid, etc.), a metal catalyst (eg, dibutyltin oxide, zinc acetate, etc.) or an alkali catalyst [eg, potassium hydroxide, sodium hydroxide, 1,8-diazabicyclo [ 5,4,0] undecene (DBU) etc.] can be used. When the catalyst is used, the amount used is preferably 0.01 to 3% by mass based on the total charged amount.

The number average molecular weight (hereinafter abbreviated as Mn) of the compound represented by the formula (1) by gel permeation chromatography (GPC) is preferably from 1,000 to 10
000, more preferably 2,000 to 80,00
0, particularly preferably 3,000 to 50,000. The viscosity at 25 ° C. is usually 10 to 10,
000 cPs, preferably 30 to 8,000 cPs, more preferably 50 to 5,000 cPs. When the molecular weight and the viscosity are in these ranges, it is preferable because it is excellent in preventing fusion between fibers and easy to handle as an oil agent.

The acid value of the compound represented by formula (1) is usually 60 or less, preferably 30 or less, particularly preferably 10 or less. Within this range, the smoothness, the heat resistance, and the uniform adhesion to the fiber become good, and a carbon fiber with higher strength tends to be obtained.

Preferred examples of the composition of the compound represented by the formula (1) include: alkylene diamine having 2 to 6 carbon atoms or polyalkylene polyamine having 4 to 12 carbon atoms.
A saturated or unsaturated fatty acid amide having 8 to 18 carbon atoms,
Compounds to which alkylene oxides having 2 and / or 3 carbon atoms are added and further esterified with the above-mentioned fatty acids may be mentioned. Specific examples include the following compounds.

[0018]

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[0019]

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[0020]

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[0021]

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In the oil agent for the carbon fiber production process of the present invention, other leveling agents, nonionic surfactants and antistatic agents can be added as long as the function of the component of the formula (1) is not impaired.

The following are examples of the smoothing agent. Mineral oil having a kinematic viscosity at 25 ° C of 10 to 3,000 cSt (for example, a kinematic viscosity at 25 ° C of 200 cS
t, refined spindle oil having a kinematic viscosity at 25 ° C. of 1
A liquid paraffin which is 00 cSt, etc.) Animal and vegetable oils (eg, tallow, sperm whale oil, coconut oil, castor oil, etc.) Fatty acid esters composed of a carboxylic acid having 8 to 32 carbon atoms and an alcohol having 4 to 32 carbon atoms (eg, isostearyl laurate) Oleyl oleate, dioleyl adipate, etc.) Alkyl ether esters composed of 1 to 10 moles of an EO adduct of a higher alcohol having 4 to 32 carbon atoms and a carboxylic acid having 8 to 32 carbon atoms (for example, E of lauryl alcohol)
O3 mol adduct laurate, EO 5 mol adduct laurate of isostearyl alcohol, etc.)

A polyether-based lubricant obtained by adding an alkylene oxide having 2 to 4 carbon atoms to a monohydric alcohol having 1 to 32 carbon atoms (for example, 1 to 100 moles added) [for example,
EO / PO random adduct of butanol (Mn = 500
EO and / or PO adduct of octyl alcohol (Mn = 300 to 10,000), and EO and / or PO adduct of stearyl alcohol (Mn = 5).
00-10,000)] Silicone compounds (for example, dimethylpolysiloxane, amino-modified silicone, phenyl-modified silicone,
Natural and synthetic waxes (eg, carnauba wax, beeswax, paraffin wax having a melting point of 30 ° C. to 100 ° C. and polyolefin wax (olefin having 2 to 18 carbon atoms, Mn = 1,000 to 10,000) , For example, polyethylene wax). Preferred among these are animal and vegetable oils,
Fatty acid esters, alkyl ether esters, polyether-based lubricants, silicone compounds and waxes,
More preferred are fatty acid esters, alkyl ether esters and polyether-based lubricants.

Examples of the nonionic surfactant include the following. An alkylene oxide adduct of 2 to 4 carbon atoms (e.g., 1 to 200 moles of addition) of an ester composed of a polyhydric alcohol having 2 to 6 or 3 to 8 or more carbon atoms and a fatty acid having 8 to 32 carbon atoms. (For example, EO 25 mol adduct of hydrogenated castor oil, EO 20 mol adduct of sorbitan trioleate, etc.) Alkylamines having 6 to 32 carbon atoms and alkylene oxide adducts having 2 to 4 carbon atoms (for example, 1 mol of addition moles) ~ 40) (for example, 1 mol adduct of EO of triethylamine, laurylamine, 7 mol adduct of EO of stearylamine, etc.) Among the above-mentioned examples of the smoothing agent, alkylene oxides having 2 to 4 carbon atoms of higher alcohols having 8 to 32 carbon atoms The adduct (for example, 1 to 100 moles of addition) also has a function as a nonionic surfactant. [For example, an EO / PO random adduct of octyl alcohol (Mn = 500 to 10,000)
00), EO and / or PO adducts of stearyl alcohol (Mn = 300 to 10,000) and the like] Of these, preferred are alkylene oxide adducts of polyhydric alcohol esters and alkylene oxide adducts of higher alcohols. More preferred are alkylene oxide adducts of higher alcohols.

The following are examples of the antistatic agent. C8-C32 alcohols and their C2-C2 alcohols
4 alkylene oxide adducts (for example, an addition mole number of 1
To 20) phosphates (e.g., potassium phosphate ester of lauryl alcohol, sodium phosphate ester of EO 2-mol adduct of stearyl alcohol, etc.) (thio) phosphite having 9 to 90 carbon atoms (e.g., triphenyl phosphite) , Trilauryl trithiophosphite, etc.) Fatty acid soap having 8 to 32 carbon atoms (counter ions are, for example, ammonium, sodium, potassium, ammonia, etc.)
(E.g., ammonium laurate soap, potassium oleate soap, castor oil sodium soap, etc.) C8-32 imidazoline-based compounds (e.g., laurylimidazoline, oleylimidazoline, etc.) C8-32 sulfuric acid esters and salts thereof (For example, lauryl alcohol sulfate sodium salt, oleyl alcohol sulfate ammonium, etc.) C8-C32 sulfonic acid and its salt (for example, dodecylbenzenesulfonic acid and its sodium salt, sulfosuccinic acid di-2-ethylhexyl sodium salt) Etc.). Of these, phosphates, (thio) phosphites and fatty acid soaps are preferred, and phosphates and fatty acid soaps are more preferred.

Further, the compound of the present invention may contain other additives and a pH adjuster as long as the performance is not impaired. Examples of the additives include the following. Antioxidants [for example, hindered phenolic 2,
6-di-t-butylphenol, triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate];
4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t-butylanilino) -1,3,5-
Triazine; etc.] UV absorber [for example, benzotriazole-based 2-
(3,5-di-t-amyl-2-hydroxyphenyl;
Hindered amine bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate; etc.] Fluorine compounds (for example, perfluoroethane, perfluorooctane, etc.).

Examples of the pH adjuster include the following. Lower fatty acids (2-8 carbon atoms) and derivatives thereof (eg, acetic acid, lactic acid, hydrochloric acid, malic acid, sodium acetate, etc.) Ammonia and alkali metal hydroxides (eg, sodium hydroxide, potassium hydroxide, lithium hydroxide) , Magnesium hydroxide, calcium hydroxide, etc.) C6 to C32 alkylamines and their C2 to C4 alkylene oxide adducts (e.g., 1 to 40 additional moles) (e.g., EO2 of triethylamine, laurylamine) Mole adduct, EO 5-mol adduct of stearylamine, etc.) Fatty acid soap having 8 to 32 carbon atoms (counter ions are, for example, ammonium, sodium, potassium, ammonia, etc.)
(Eg, ammonium laurate soap, potassium oleate soap, castor oil sodium soap, etc.).

The content of the compound represented by the general formula (1) and the content of other leveling agents, nonionic surfactants, antistatic agents and the like in the oil agent of the present invention are not particularly limited. From the viewpoint of maintaining high heat resistance and anti-fusing property, it is preferable that the compound represented by the general formula (1) be contained in an amount of 40% by mass or more based on the total mass of the oil after blending. It is more preferably at least 50% by mass, particularly preferably 70 to 95% by mass. In addition, the content of the smoothing agent in the oil agent of the present invention is usually 0 or 1 to 60% by mass [however, the content in the case of using a silicone compound as the smoothing agent is particularly low in the ash content in the carbon fiber production process. 0 or 0.1 to satisfy the performance of
10% by mass, preferably 0 or 1 to 5% by mass], and the content of the nonionic surfactant is 0 or 1 to 20% by mass [however,
When used as a nonionic surfactant, the content is the same as the content of the above-mentioned leveling agent], and the content of the antistatic agent is 0 or 0.1 to 7
%, The content of other additives is 0 or 0.01 to 5
% By mass. Similarly, the pH adjusting agent is used in an amount (for example, 0 to 5% by weight) such that the pH of a 10% aqueous solution of the oil agent is usually 4 to 10, preferably 5 to 9, particularly preferably 6 to 8 [ Since the non-ionic surfactant and the antistatic agent also function as an antistatic agent among the pH adjusters, it is preferable to use the contents of the above nonionic surfactant and antistatic agent, respectively. ]. The total content of other components other than the compound represented by the general formula (1) is usually 60% by mass or less, preferably 0.001 to 50, based on the total mass of the oil agent.
%, More preferably 5 to 30% by mass.

In the present invention, the method of mixing the compound represented by the general formula (1) with other components is not particularly limited, and an appropriate method may be adopted according to the use form of the oil agent using a conventionally known method. Can be. For example, a method in which the compound represented by the general formula (1) and other components are directly blended using a blending tank equipped with a stirring blade or a kneader, and then heated and mixed if necessary; represented by the general formula (1) A method in which the compound and other components are separately diluted, emulsified, and the like, and then blended is exemplified.

Regarding the application form of the oil agent of the present invention, it can be treated in any state, that is, non-water-containing or water-emulsified emulsion. When performing non-water-containing treatment, use crude oil or dilute it with a diluent. The dilution ratio is not particularly limited, but the content of the oil agent is preferably 1 to 80% by mass, more preferably 5 to 70% by mass, based on the total mass of the diluted solution after dilution. The content of the compound represented by the general formula (1) is preferably from 0.4 to 80% by mass, more preferably from 2 to 65% by mass, based on the total mass of the diluted solution after dilution.

Examples of the diluent include organic solvents [alcohols such as ethylene glycol, propylene glycol, methanol and isopropanol; ethers such as diethyl ether; aliphatic hydrocarbons such as hexane; aromatic hydrocarbons such as toluene and xylene; Ketones such as methyl ethyl ketone; polar solvents such as dimethylformamide; halogenated hydrocarbons such as chloroform and carbon tetrachloride]; and low-viscosity (less than 10 cSt) mineral oil (liquid paraffin having a kinematic viscosity at 25 ° C. of 0.5 to 5 cSt; Refined spindle oil and the like).

When processing as an emulsion,
If necessary, an emulsifier (the above-mentioned nonionic surfactants can be used) is blended with the present oil agent, and the oil agent is used after emulsification in water. The method of blending the emulsifier into the oil, for example, after mixing the present oil with the above-mentioned organic solvent and low-viscosity mineral oil, if necessary, a method of adding an emulsifier thereto with stirring can be applied. For example, a method in which the above-mentioned oil agent mixture is added thereto while stirring warm water at 30 ° C. to 60 ° C. can be applied. The amount of the emulsifier is usually from 0 to 50% by mass, based on the total mass of the oil agent. As an emulsifying machine, an emulsifying tank equipped with stirring blades,
A ball mill, a Gaulin homogenizer, a homodisper, a bead mill, or the like can be used. The dilution ratio is not particularly limited, but the content of the oil agent is preferably 0.01 to 30% by mass, more preferably 0.2 to 20% by mass based on the total mass of the emulsion after emulsification. The content of the compound represented by the general formula (1) is preferably 0.004 to 30 based on the total mass of the emulsion after emulsification.
%, More preferably 0.08 to 18% by mass.

The oil agent of the present invention can be applied in the precursor manufacturing process of the carbon fiber manufacturing process, such as after spinning, before stretching, after stretching, and before winding.
It is preferably applied after spinning or before stretching. Further, it can be applied at a stage immediately before the flame-proofing step. Further, it can be applied in a step after the flame resistance and before the carbonization.

The method of lubrication is not particularly limited, and a method of dipping (dipping) the yarn in a tank containing an oil agent and then squeezing the mixture with a roller or the like to a predetermined amount (dip method) is generally used. But nozzle oiling, roller oiling,
Alternatively, spray oiling or the like is also applicable. The amount of the oil agent of the present invention applied to the precursor is usually 0.1 part based on the fiber mass after spinning and drying, in terms of pure components (components other than water and diluent).
It is from 0.01 to 10% by mass, preferably from 0.05 to 5% by mass. If the amount of the above component is less than 0.01% by mass, winding around a roller or a guide is likely to occur, and 10% by mass.
If it is larger, fusion of the fibers is likely to occur.

[0036]

The present invention will be described below with reference to examples, but the present invention is not limited to these examples. In the following, parts mean parts by mass, and% means mass%.

Example 1 80 parts of a compound represented by the following formula (2), 15 parts of isostearyl laurate, and an EO / PO random adduct of octyl alcohol (Mn: 2,0
00) 4 parts, 0.5 part of potassium salt of phosphoric acid ester of lauryl alcohol, and 0.5 part of triethylene glycol-bis [3- (3-t-butyl-5-methyl-4-hydroxyphenyl) propionate]. The mixture was stirred and mixed at 20 ° C. to obtain the oil agent [1] of the present invention.

[0038]

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Example 2 Example 1 was repeated except that the compound represented by the formula (2) was replaced with a compound represented by the following formula (3).
The oil agent [2] of the present invention was obtained in the same manner as described above.

[0040]

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<Comparative Example 1> A compound represented by the formula (2) was prepared by subjecting an amino equivalent to 1,800 and a viscosity (25 ° C.) to 1,2.
A comparative oil agent [1] was obtained in the same manner as in Example 1 except that the amino-modified silicone which was 00 cSt was used.

Comparative Example 2 The compound represented by the formula (2) was prepared by converting the compound represented by the formula (2) to an amino equivalent = 3,000 and a viscosity (25 ° C.) = 3.5.
A comparative oil agent [2] was obtained in the same manner as in Example 1 except that the amino-modified silicone that was 00 cSt was used.

Example 3 and Comparative Example 3 (1) Production of Precursor A 20% dimethyl sulfoxide (DMSO) solution of a polyacrylonitrile polymer obtained by copolymerizing 99% of acrylonitrile and 1% of itaconic acid was added to a 50% DMSO aqueous solution. Acrylic tow was obtained by extrusion wet spinning. After washing with water, the film is stretched in hot water at 90 ° C. and dried to form a precursor (3
(0,000 denier / 12,000 filaments). (2) Flame resistance The oil agent of the present invention obtained in Examples 1 and 2 and the comparative oil agent obtained in Comparative Examples 1 and 2 were each applied to the precursor obtained above so that the amount of adhesion was 0.5%. And heated at 130 ° C. for 60 seconds. This was held in an iron metal frame so that a tension of 0.01 g per single yarn denier was applied, and then the metal frame and the metal frame were allowed to stand in a circulating drier at 250 ° C. for 60 minutes to obtain flame-resistant fibers. (3) Carbonization The oxidized fiber obtained above was used in an amount of 0.01 per denier of a single yarn.
g, while applying a tension of 300 g in a nitrogen atmosphere.
The carbon fiber was obtained by firing in a carbonization furnace at 00 ° C. (temperature gradient of 50 ° C./min) and 1400 ° C. for 10 minutes.

The oil agent of the present invention obtained in Examples 1 and 2,
With respect to the comparative oils obtained in Comparative Examples 1 and 2, the results of measuring and evaluating the fiber splitting property, adhesion resistance, smoothness, antistatic property, ash content after heating and carbon fiber strength by the following methods, respectively, are shown in Table 1. Shown in

<Evaluation of Fiber Separation Property> Example 3 and Comparative Example 3
In the above, after the oil agent treatment, the precursor tow obtained by heating at 130 ° C. for 60 seconds was cut into a length of about 2 cm, and the fibrillation of single fibers was observed on black paper. Evaluation criteria ◎: Single fibers are not adhered and single fibers are scattered (excellent fiber separation properties) ○: Almost no single fibers are adhered, but there are parts where single fibers are not separated (splitting properties) Good: Δ: Adhesion of monofilaments in a considerable portion, and many portions that do not disintegrate monofilaments (defective fiber separation) ×: Almost monofilaments are adhered, and monofilaments hardly disintegrate (min. Very poor fineness)

<Evaluation of Adhesion Resistance> The oxidized fiber obtained in Example 3 and Comparative Example 3 was cut into a length of about 2 cm, and the adhesion of the fiber was observed on white paper. Evaluation criteria ：: No single fiber adhesion observed ○: Slight single fiber adhesion △: Single fiber adhesion observed in some places ×: Single fiber adhesion extremely large

<Evaluation of Smoothness> An oil agent was applied to an acrylic filament (300 denier / 300 filament) by a dipping method so as to have an adhesion amount of 0.5%.
g, contacted with a chrome-plated satin pin at a yarn speed of 50 m / min, and the friction coefficient between the acrylic filament and the satin pin was determined using a tensiometer (manufactured by Eiko Sokki). The smaller the value, the better the smoothness.

<Evaluation of antistatic property> The static electricity generated on the satin pin during the evaluation of the smoothness was measured by a current collecting potential difference measuring device (KS-525, manufactured by Kasuga Electric Co., Ltd.). Evaluation criteria ◎: Almost no generation of static electricity (generated electricity: -50 to
+: 50 V) ：: Slight static electricity generation (generated electricity amount: -500 to -50)
V, +50 to +500 V) ×: A large amount of static electricity is generated (the amount of generated electricity: less than -500 V, +
Over 500V)

<Ash after heating> The ash of each oil agent was measured based on the ash test described in JIS-K-0067, the first method.

<Evaluation of Carbon Fiber Strength> Using the carbon fibers obtained in Example 3 and Comparative Example 3, JIS-R-
The strand strength was measured according to the method described in 7601.

[0051]

[Table 1]

[0052]

The oil agent for the carbon fiber production process of the present invention has excellent heat resistance, lubricity and antistatic properties (precursor separation properties,
In addition to having excellent adhesion prevention properties, it has excellent processability (less fluff and yarn breakage in the precursor manufacturing process and the flameproofing process). Therefore, by using the oil agent of the present invention, a high-performance, high-strength, high-elasticity carbon fiber can be stably obtained. Furthermore, since there is little generation of ash after firing and there is very little risk of damaging the carbon fiber production furnace, it exhibits the performance of ensuring long-term operation stability.

Claims (6)

[Claims] 1. An oil agent for a carbon fiber production process, comprising one or more compounds represented by the following general formula (1). Wherein X: a hydrogen atom or a monocarboxylic acid residue R: a hydrocarbon group having 2 to 32 carbon atoms A: a hydrocarbon group having 2 to 10 carbon atoms m: an integer of 1 to 100 n: 1 to 500 Integer A plurality of X, R, A, and n may be the same or different. ] 2. The oil agent according to claim 1, wherein R is at least one group selected from an ethylene group, a 1,3-propylene group and a phenylene group. 3. The oil agent according to claim 1, wherein A is an ethylene group and / or a propylene group. 4. The method according to claim 1, further comprising at least one selected from a leveling agent, a nonionic surfactant and an antistatic agent.
The oil agent according to any one of the above. 5. The oil agent according to any one of claims 1 to 4,
A method for treating a precursor fiber of carbon fiber, wherein the precursor fiber of carbon fiber is provided with 0.01 to 10% by mass as a pure component based on the mass of the treated fiber. 6. A carbon fiber produced using the oil agent according to claim 1. Description: