JPH10204780A - Treatment of polyester fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simply give polyester fiber the adhesivity to rubber formulation through the single bath treatment by treating the fiber with a treatment agent containing polyvinyl formamide, aromatic polyepoxide, blocked polyisocyanate and resorcinol formalin rubber latex. SOLUTION: This treatment agent contains (A) polyvinyl formamide, (B) aromatic polyepoxide, (C) blocked polyisocyanate and (D) resorcinol formalin rubber latex and polyester fiber for reinforcing rubber is treated with this agent. When the proportions of individual components in the treatment agent are represented by WA-WD in % by weight on the solid basis, WA/(WB+ WC)=1/100-60/100, WB/WC=8/2-1/9 and (WB+WC)/WD=4/6-1/9 are suitable.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for treating polyester fibers. More specifically, the present invention relates to a simple one-bath treatment method for imparting adhesion to a rubber compound to a polyester fiber.

[0002]

2. Description of the Related Art Polyester fibers represented by polyethylene terephthalate fibers have excellent physical properties such as high strength and high Young's modulus.
It is widely used as a rubber reinforcing fiber for hoses and belts. However, since the surface of the polyester fiber is relatively inert, the adhesiveness of the polyester fiber to a matrix such as rubber or resin is insufficient, and the physical properties of the polyester fiber cannot be sufficiently exhibited.

[0003] For this reason, a chemical treatment method in which the surface of the polyester fiber is treated in advance with various chemicals, for example, by applying a highly reactive chemical such as an aliphatic epoxide compound or a blocked isocyanate compound to impart adhesiveness. later,
A so-called two-bath treatment method for treating resorcinol-formalin rubber latex (RFL) has been proposed and put to practical use. However, although this method can provide good adhesive strength, the process is complicated due to the two-stage treatment,
It has drawbacks such as the need to install new equipment.

On the other hand, as a one-bath treatment method, a resorcinol-formalin rubber latex (RFL) solution is mixed with a reaction product of p-chlorophenol, resorcinol and formalin (for example, 2,6-bis (2 ', 4'). -Dihydroxyphenylmethyl) -4-chlorophenol) is known (Japanese Patent Publication No. 46-1).
No. 1251 and Japanese Patent Publication No. 56-2155). However, this method does not provide sufficient adhesive performance,
In particular, they are not satisfactory as rubber reinforcing fibers for tires and the like.

[0005] Further, in the above-mentioned conventional bonding treatment method, when the rubber composition is exposed to a high temperature for a long time, the adhesive force between the polyester fiber and the rubber compound is remarkably reduced. Due to its drawbacks, its use conditions and applications have been limited.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a simple one-bath adhesion treatment method which is excellent in adhesion performance between a polyester fiber and a rubber compound. Is to provide.

[0007]

Means for Solving the Problems The object of the present invention is to provide:
"Polyester fibers are made of polyvinyl formamide (A), aromatic polyepoxide compound (B), blocked polyisocyanate compound (C), and resorcinol.
A method for treating polyester fibers, comprising treating with a treatment agent containing formalin rubber latex (RFL). Is achieved.

[0008]

DETAILED DESCRIPTION OF THE INVENTION The present invention can be applied to any polyester fiber. In particular, a fiber comprising a polyester containing terephthalic acid or naphthalenedicarboxylic acid as a main acid component and ethylene glycol or tetramethylene glycol as a main glycol component is used. It is preferably used. The denier, the number of filaments, the cross-sectional shape, the fiber properties, the fine structure, the polymer properties (terminal carboxyl group concentration, molecular weight, etc.) of the polyester fiber, and the presence or absence of additives in the polymer are not limited at all. Also,
The polyester fibers referred to in the present invention include various fiber aggregate forms such as yarns, cords, nonwoven fabrics, woven and knitted fabrics.

It is important that the treating agent for treating such polyester fibers contains polyvinyl formamide (A). This polyvinyl formamide is oxalic acid amide of polyvinylamine, and generates a primary amine by heat treatment in an alkaline atmosphere, and the action of this amine improves the adhesiveness with polyester fiber, particularly the heat-resistant adhesiveness. is there.

By the way, it is known that the polyamine component has an excellent affinity for polyester fiber due to its hydrogen bonding ability and chemical reactivity, and provides high adhesion at high temperatures. However, amines generally exhibit cationicity in an aqueous solution, and consequently form a salt with an anionic surfactant generally used as a dispersant for other components in the treating agent, and consequently the dispersibility decreases. It is difficult to treat polyester fibers using the amine as it is. On the other hand, since polyvinyl formamide generates a primary amine by heat treatment in an alkaline atmosphere as described above, when blended in an adhesive treatment agent, the dispersibility does not decrease and the treatment is performed stably. On the other hand, by heating after being attached to the polyester fiber, an amine can be generated to improve the adhesiveness.

The aromatic polyepoxide compound (B) used in the present invention is a compound having at least one aromatic ring and at least two epoxy groups in the molecule.
The content of the epoxy group is at least 2 equivalents, preferably 3 to 7 equivalents, and particularly preferably 4 to 5 equivalents per 1 kg of the compound. When the polyepoxide compound is aliphatic,
Resorcin, formalin, rubber latex (R
Since the reactivity with the FL) solution is too high, the treating agent gels during the treatment of the polyester fiber, and the resulting adhesive performance decreases with the lapse of time after adjusting the treating agent.

The aromatic polyepoxide compound includes a reaction product of a polyhydric phenol and a halogen-containing epoxide such as epichlorohydrin, for example, resorcin, bis (p-hydroxyphenyl) methane, 1,1,1,2
2,2-tetrakis (p-hydroxyphenyl) ethane, bis (4-hydroxyphenyl) dimethylmethane,
Examples thereof include reaction products of phenol / formaldehyde resin, cresol / formaldehyde resin, resorcin / formaldehyde resin and epichlorohydrin, and aromatic epoxy resins which are reaction products of bisphenol A and epichlorohydrin. Of these, glycidyl ethers of phenolic resins represented by the following formula (Formula 2) are preferred.

[0013]

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The aromatic polyepoxide compound is usually used as an emulsion or dispersion. To prepare an emulsion or dispersion, for example, the aromatic polyepoxide compound as it is or dissolved in a small amount of a solvent as required, and a known emulsifier, for example, sodium alkylbenzene sulfonate, dioctyl sulfosuccinate sodium salt, nonylphenol What is necessary is just to emulsify or disperse using an ethylene oxide adduct etc.

The blocked polyisocyanate compound (C) used in the present invention is an addition compound of a polyisocyanate compound and a blocking agent, and the blocking agent component is released by heating to form an active polyisocyanate compound. It is a thing to tighten. Examples of the polyisocyanate compound include polyisocyanates such as tolylene diisocyanate, metaphenylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, polymethylene polyphenyl isocyanate, and triphenylmethane triisocyanate, or those polyisocyanates and two or more active hydrogen atoms. Such as trimethylolpropane, pentaerythritol, etc., in a molar ratio of isocyanate group (-NCO) to hydroxyl group (-OH) of more than 1 and a terminal isocyanate group-containing polyol adduct polyisocyanate. Is mentioned. In particular, aromatic polyisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, and polymethylene polyphenyl isocyanate are preferred because they exhibit excellent performance.

Examples of the blocking agent include phenols such as phenol, thiophenol, cresol and resorcin; aromatic secondary amines such as diphenylamine and xylidine; lactams such as phthalimide, caprolactam and valerolactam; Oximes such as acetoxime, methyl ethyl ketone oxime and cyclohexanone oxime, and sodium acid sulfite.

Such a blocked polyisocyanate compound is usually used as an emulsion, dispersion or aqueous solution.
In order to prepare an emulsion or dispersion, for example, such a blocked polyisocyanate is dissolved as it is or as necessary in a small amount of a solvent in the same manner as the above-mentioned aromatic polyepoxide compound, and then a known emulsifier such as an alkylbenzenesulfonic acid is used. What is necessary is just to emulsify or disperse using soda, dioctyl sulfosuccinate sodium salt, nonylphenol ethylene oxide adduct, etc.

The resorcinol-formalin rubber latex contained in the treating agent of the present invention is generally called RFL, and is obtained by mixing and aging a rubber latex with an initial condensate of resorcinol and formaldehyde. , The molar ratio of resorcinol to formaldehyde is 1: 0.
It is used in the range of 1-1: 8, preferably 1: 0.5-1: 5, particularly preferably 1: 1-1: 4.

Examples of the rubber latex include natural rubber latex, styrene / butadiene copolymer latex, vinylpyridine / styrene / butadiene terpolymer latex, nitrile rubber latex, chloroprene rubber latex and the like, and these may be used alone or in combination. . Among them, vinyl pyridine, styrene,
It is preferable to use butadiene terpolymer latex alone or in combination. In the case of combined use, excellent performance is exhibited when used in an amount of 1/3 or more of the total latex weight.

The mixing ratio of resorcinol-formalin and rubber latex is determined by the above-mentioned aromatic polyepoxide compound (B) and blocked polyisocyanate compound (C)
Varies depending on the addition ratio of the former, but the former in terms of the solid content weight ratio:
The latter is suitably in the range of 1: 1 to 1:15, particularly 1: 3 to 1:12. If the proportion of the rubber latex is too small, the treated polyester fiber material becomes hard and the fatigue resistance tends to decrease. Conversely, if the proportion is too large, it becomes difficult to obtain satisfactory adhesive strength and rubber adhesion rate.

The compounding weight ratio of each component of polyvinyl formamide (A), aromatic polyepoxide compound (B), blocked isocyanate compound (C), and resorcinol-formalin rubber latex (RFL) is W _A / (W
_B + W _C) is 1 / 100-60 / 100, especially 1/10
Range to 3/10 are suitable, W _B / W _C 8/2
1/9, especially 8 / 2-4 / 6 range are suitable, further _{(W B + W C) /} W RFL 4 / 6-1 / 9, particularly 5 /
A range of 5/2/8 is appropriate. W _A , W _B ,
W _C and W _RFL are the weight percentages of polyvinyl formamide (A), aromatic polyepoxide compound (B), blocked isocyanate compound (C), and resorcinol-formalin rubber latex (RFL) in the treating agent, respectively.
Represents

Here, when W _A / (W _B + W _C ) is smaller than the above range, the effect of improving the adhesive performance, especially the heat-resistant adhesion performance, is reduced. And the processing becomes difficult. W _B / W
_{When C} is out of the above range, rubber adhesion to polyester fibers tends to decrease. Further, (W _B + W _C ) / W
_{When the RFL} is larger than the above range, the treated polyester fiber may be hardened and the fatigue resistance may be reduced. On the other hand, when the _RFL is smaller than the above range, the adhesive performance tends to be reduced.

The above-mentioned polyvinyl formamide (A), aromatic polyepoxide compound (B), blocked polyisocyanate compound (C) and resorcinol-formalin.
The treating agent of the present invention containing rubber latex (RFL) has a total solid concentration of 1 to 30% by weight, preferably 5 to 2%.
It is used so as to be 5% by weight. If the treating agent concentration is lower than this range, the adhesiveness decreases, while if the treating agent concentration is too high, the composition becomes hard and the fatigue resistance tends to decrease.

To apply the treating agent to the polyester fiber material, any method such as contact with a roller or application by spraying from a nozzle or immersion in a solution can be adopted. The solid content adhered to the polyester fiber is suitably in the range of 0.1 to 10% by weight, preferably 2 to 7% by weight. In order to control the amount of solids adhering to the fiber, means such as squeezing with a pressing roller, scraping with a screver, blowing off with air blowing, suction, and hitting with a beater may be employed. Also, it may be applied a plurality of times to increase the amount of adhesion.

In the present invention, after the polyester fiber is treated with a treating agent, the temperature is at least 50 ° C. and at least 10 ° C. lower than the melting point of the polyester fiber, preferably from 220 to 250 ° C.
Drying and heat treatment at a temperature of 0.5 ° C. for 0.5 to 5.0 minutes, preferably 1 to 3 minutes. If the drying and heat treatment temperatures are too low, the adhesion to rubbers tends to be insufficient, while if the temperature is too high, the polyester fibers are melted and fused, or the strength is significantly reduced, so that the polyester fibers cannot be put to practical use.

[0026]

The present invention will now be described more specifically with reference to examples. The strength, elongation, and 6.8 in Examples
Kg heavy load elongation, hardness, cord peeling adhesive strength, and cord pulling adhesive strength were measured according to the following methods.

<Strength, elongation, 6.8 kg heavy load elongation> The polyester cord after the bonding treatment was subjected to JIS L1013.
To determine the strength and elongation at the cutting point and the elongation under a heavy load of 6.8 kg.

<Cord Peel Adhesion (CRA)> This shows the adhesion between the treated cord and the rubber. 7 near the surface layer of the unvulcanized rubber sheet containing carcass containing natural rubber as the main component
Fill the code of the book, 150 ℃, 30 minutes, 50Kg / c
Vulcanization was performed at a pressing pressure of 50 mg / cm ² (a heat resistance value) at 180 ° C. for 60 minutes at a pressing pressure of 180 m ² (initial value). The force required for peeling at a speed of 200 mm / min in the direction of degrees is indicated by Kg / 5.

<Cord pull-out adhesive strength (T)> This shows the shear adhesive strength between the treated cord and rubber. Embed the cord in an unvulcanized rubber block containing carcass containing natural rubber as a main component, at 150 ° C. for 30 minutes (initial value) or 18
After vulcanizing at 0 ° C. for 60 minutes (heat resistance value), the cord was pulled out of the rubber block at a speed of 200 mm / min, and the force required for pulling was expressed in kg / 7 mm.

<Hardness> The hardness was measured according to the method of JIS L1085.

Example 1 2.8 g of a 10% aqueous sodium hydroxide solution and 7.7 g of a 28% aqueous ammonia solution were added to water 5
In addition to 2.6 g, 7.3 g of Sumikanol 700S (65% by weight resorcinol-formalin initial condensate solution, manufactured by Sumika ABS Latex Co., Ltd.) was added to the aqueous solution obtained by well stirring, and the mixture was sufficiently stirred. And disperse. Next, 70.1 g of Nippol 2518FS (a vinyl pyridine styrene-butadiene terpolymer latex 40% by weight aqueous emulsion manufactured by Zeon Corporation) and Nippol LX-112 (a styrene-butadiene copolymer manufactured by Zeon Corporation) 30.0 g of a 40% by weight aqueous emulsion is diluted with 77.3 g of water. The resorcinol-formalin initial condensate dispersion is added to the diluent with gentle stirring, and 1.8 g of formalin (37% by weight aqueous solution) is further added and uniformly mixed.

Next, 24.1 g of ECN1400 (a 40% by weight aqueous emulsion of polyglycidyl ether of cresol novolak type resin, manufactured by Asahi Ciba Co., Ltd.) was added to this mixture, and DM was added.
12.5 g of 6011 (manufactured by Meisei Chemical Co., Ltd., 33% by weight of acetoxime blocked diphenylmethane diisocyanate in water) and PNVF (manufactured by Mitsubishi Chemical Corporation)
13.8 g of a 30% by weight aqueous solution of polyvinyl formamide)
And mix uniformly.

Polyethylene terephthalate having an intrinsic viscosity of 0.95 is melt-spun and drawn according to a conventional method to obtain a multifilament of 1500 denier / 192 filaments.
And a cord of 3000 denier / 384 filaments was obtained.

This cord was immersed in the above-mentioned treating agent using a computer treater (tire cord processor manufactured by CA Ritzler Co., Ltd.), dried at 130 ° C. for 2 minutes, and subsequently at 245 ° C. and 220 ° C. Heat treatment is performed twice for 1 minute each. The treated polyester tire cord had 6.8% by weight of the solid content of the treating agent attached to the fiber weight.

The thus obtained treatment cord is embedded in an unvulcanized rubber containing a carcass containing natural rubber as a main component,
Vulcanization was performed at 150 ° C. for 30 minutes. Table 1 shows the evaluation results.

Examples 2 to 3, Comparative Example 1 The amounts of polyvinyl formamide, aromatic polyepoxide compound and blocked polyisocyanate compound were changed as shown in Table 1, and the procedure was repeated. The evaluation results are shown in Table 1.

[0037]

[Table 1]

[0038]

According to the method of the present invention, since a treating agent in which polyvinyl formamide, an aromatic polyepoxide compound and a blocked polyisocyanate compound are blended in the RFL solution is used, the conventional one-bath type adhesive treating agent is used. Adhesion between polyester fibers and rubbers compared to the method used,
In particular, the heat-resistant adhesiveness is good, and since it is a one-bath type, the adhesive treatment can be easily performed.

Claims (3)

[Claims] 1. A method for treating a polyester fiber with a treating agent containing polyvinyl formamide (A), aromatic polyepoxide compound (B), blocked polyisocyanate compound (C), and resorcinol-formalin rubber latex (RFL). A method for treating a polyester fiber, comprising: 2. The solid content weight ratio (W _A / (W) of polyvinyl formamide (A), aromatic polyepoxide compound (B) and blocked polyisocyanate compound (C).
_B + W _C)) is 1 / 100-60 / 100, aromatic polyepoxide compound (B) with the blocked polyisocyanate compound (C) and the solid weight ratio of (W _B / W _C) is 8 /
2 to 1/9, and aromatic polyepoxide compound (B) and blocked polyisocyanate compound (C)
And resorcinol-formalin rubber latex (RF
L) and the solid content weight ratio of _{((W B + W C)} / W RFL) is 4
The method for treating polyester fiber according to claim 1, wherein the ratio is from / 6 to 1/9. 3. The method according to claim 1, wherein the aromatic polyepoxide compound (B) is
The method for treating a polyester fiber according to claim 1 or 2, wherein the method is a glycidyl ether of a phenol / formaldehyde resin represented by the following formula (Formula 1). Embedded image