JPH10273880A - Adhesive treatment of polyester fiber - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing polyester fiber whose adhesiveness to esp. ethylene-propylene-based rubber latex is improved. SOLUTION: This method comprises treating polyester fiber with the first treating liquid containing a polyepoxide compound and subsequently treating it with a treating agent containing resorcinol/formalin/rubber latex(RFL), blocked polyisocyanate compound and chlorophenol compound, wherein there is used, as the rubber latex, a polybutadiene rubber latex having a particle size distribution satisfying the relationships, an average particle size <=0.30 μm, the maximum particle size <=0.50 μm, and particles each <=0.30 μm in size accounts for >=90 cumulative % in a particle size distribution measured by using the sodium alginate method.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for bonding polyester fiber and rubber, and more particularly, to a method for bonding polyester fiber and ethylene propylene rubber (EPDM). Rubber hoses, diaphragms, with reinforcement layers and fiber base fabrics
V-belts, conveyor belts and the like can be mentioned.

[0002]

2. Description of the Related Art Polyester fibers represented by polyethylene terephthalate fibers have high strength and high Young's modulus, and are utilized widely as rubber reinforcing fibers for tires, hoses, belts and the like.

However, in the field of hoses and belts, since the temperature of the engine room of the automobile becomes high, the rubber material is changing to one having excellent high-temperature characteristics. One of them is an ethylene propylene rubber. However, the rubber has very few double bonds in the chemical structure and has poor reactivity, so that it is very difficult to bond the rubber.

Further, since the surface of the polyester fiber is relatively inert, a method of treating the polyester fiber with an epoxy compound, an isocyanate compound or the like when bonding the polyester fiber to the ethylene propylene rubber (Japanese Patent Application Laid-Open No. 54-1979). No. 77794, JP-A-60-990
No. 76, JP-A-60-21924, etc.) or a method of increasing the reactivity of the rubber by using a highly polar chlorosulfonated polyethylene latex or a special chlorophenol compound (JP-B-3-20136, etc.) )
However, it is a reality that no satisfactory adhesive force is obtained in any of the methods.

To solve such a problem, Japanese Patent Laid-Open No.
JP-138880 discloses a method of treating a polyester fiber with a treating agent containing a polyepoxide compound and then treating it with a treating agent containing resorcinol-formalin rubber latex (RFL), a blocked polyisocyanate compound and a chlorophenol compound. However, in this method, there is a problem that the adhesive layer formed on the fiber surface has a low cohesive force and does not exhibit a sufficient adhesive force.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a polyester fiber having improved adhesion to an ethylene propylene rubber matrix. It is to provide a manufacturing method.

[0007]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to achieve the above object, and have found that the cohesive force of the adhesive layer is closely related to the particle size of the rubber latex used. It has been found that when the particle diameter is controlled to a specific range, the cohesive force of the adhesive layer is increased, and the adhesiveness between the ethylene propylene rubber matrix and the polyester fiber can be improved.

Thus, according to the present invention, after treating a polyester fiber with a first treating agent containing a polyepoxide compound, resorcinol-formalin rubber latex (RF)
L) When treated with a treating agent containing a blocked polyisocyanate compound and a chlorophenol compound, a particle size distribution satisfying the following (a) to (c) simultaneously as a rubber latex in a particle size distribution measurement by a sodium alginate method. The present invention provides a method for bonding polyester fibers, characterized by using a polybutadiene rubber latex having the following formula: (A) Average particle size ≦ 0.30 μm (b) Maximum particle size ≦ 0.50 μm (c) 90% or more of particles having a particle size of 0.30 μm or less

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The polyester fibers used in the present invention are polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate and the like. It goes without saying that the molecular weight, denier, number of filaments, cross-sectional shape, fiber properties, microstructure, presence or absence of additives, and polymer properties (terminal carboxyl group concentration, etc.) of the polyester fiber are not limited at all.

[0010] The polyepoxide compound used in the first treating agent of the present invention is a compound containing at least two epoxy groups per molecule in an amount of 0.2 g equivalent or more per 100 g of the compound, such as ethylene glycol, glycerol, and sorbitol. Reaction products of polyhydric alcohols such as pentaerythritol and polyethylene glycol with halogen-containing epoxides such as epichlorohydrin,
Unsaturated with reaction products of polyhydric phenols such as resorcinol bis (4-hydroxyphenyl) dimethylmethane, phenol-formaldehyde resin, resorcinol-formaldehyde resin and halogen-containing epoxides, or peracetic acid or hydrogen peroxide And polyepoxide compounds obtained by oxidizing the compounds.

Specific examples of the above compounds include 3,4-epoxycyclohexene epoxide, 3,4-epoxycyclohexenemethyl 3,4-epoxycyclohexenecarboxylate, and bis (3,4-epoxy-6-methyl-
(Cyclohexylmethyl) adipate and the like.

Among them, a reaction product of a polyhydric alcohol and epichlorohydrin, that is, a polyglycidyl ether compound of a polyhydric alcohol is preferable because it exhibits excellent performance. The compound is usually used as an emulsion. In order to prepare an emulsion or a solution, the compound is dissolved as it is or in a small amount of a solvent as required, and a known emulsifier such as sodium alkylbenzene sulfonate, sodium dioctyl sulfosuccinate, nonylphenol ethylene oxide adduct and the like are used. And emulsify or dissolve.

[0013] The amount of the polyepoxide compound contained in the first treating agent attached to the fibers is 0.1 to 1 with respect to the fiber weight.
0% by weight is preferable, and 0.5 to 5% by weight is more preferable.

The amount of the polyepoxide compound attached is 0.1
If the amount is less than 10% by weight, the effect of the polyepoxide compound is not sufficiently exerted, and satisfactory adhesive performance between the polyester fiber and the ethylene propylene rubber cannot be obtained. On the other hand, if the adhesion amount of the polyepoxide compound exceeds 10% by weight, the fiber becomes very hard, and the impregnating property of the treating agent to be treated later is reduced, so that the adhesive performance is reduced.

The polyepoxide compound can be added in advance together with a spinning oil or the like in the spinning process. At this time, the adhesion amount of the polyepoxide compound was 0.1
~ 0.5% by weight is most preferred.

The resorcinol-formalin rubber latex applied as the second treating agent of the present invention is an initial condensate obtained by reacting resorcinol-formalin (RF) under an alkali or acidic catalyst, a special chlorophenol compound,
It is a mixture of rubber latex, blocked polyisocyanate compound, rosin-based and / or terpene-based resin emulsion. Regarding the mixing ratio of resorcin, formalin, and rubber latex, effects can be obtained by applying any of the known techniques.

The mixing ratio of the special chlorophenol compound and resorcinol / formalin / rubber latex may be appropriately adjusted depending on the mixing ratio of the rubber to be adhered. 50/50 to 80/20 (weight ratio) is preferred.

The special chlorophenol compound used herein is a compound obtained by co-condensing parachlorophenol and resorcinol with formaldehyde, and is represented by the following structural formula: trinuclear (I), pentanuclear (II), and hexanuclear: Those containing the body (III) as a main component are preferred.

[0019]

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The rubber latex used in the second treating agent is a mixture of a vinylpyridine / styrene / butadiene terpolymer latex and a polybutadiene latex. The compounding ratio of these rubber latexes may be appropriately adjusted according to the characteristics of the rubber to be adhered, and the vinyl pyridine / styrene / butadiene terpolymer latex /
Polybutadiene latex is usually 70/30 to 30/7
It is generally used at 0 (weight ratio).

The polybutadiene latex used at this time must have a particle size distribution that simultaneously satisfies the following (a) to (c) in the particle size distribution measurement by the sodium alginate method. (A) Average particle size ≦ 0.30 μm (b) Maximum particle size ≦ 0.50 μm (c) 90 cumulative% or more of particles having a particle size of 0.30 μm or less The particle size distribution of the polybutadiene latex is as described in (a) to above.
If it deviates from (c), the cohesive force of the adhesive layer formed on the fiber surface is low, and sufficient adhesive strength is not exhibited.

The lower limits of the average particle diameter and the maximum particle diameter are not particularly limited, but are practically about 0.01 μm.

Further, the mixing ratio of resorcinol-formalin and rubber latex can obtain an effect by applying any of the known techniques.

The second treating agent is usually used by adding a blocked polyisocyanate compound. The blocked polyisocyanate compound is an addition compound of the polyisocyanate compound and the blocking agent, and releases a blocking component upon heating to generate an active polyisocyanate compound.

As the above polyisocyanate compound,
For example, polyisocyanates such as tolylene diisocyanate, metaphenylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, polymethylene polyphenyl polyisocyanate, and triphenylmethane triisocyanate, or compounds having these polyisocyanates and two or more active hydrogen atoms such as trimethylol Polyalkylene glycol adduct polyisocyanate having a terminal isocyanate group obtained by reacting propane, pentaerythritol, or the like with a molar ratio of the isocyanate group (—NCO) to the hydroxyl group (—OH) exceeding 1 is exemplified.

Of these, 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 resorcinol; aromatic secondary amines such as diphenylamine and xylidine; phthalimides, caprolactam and valerolactam. Oximes such as lactams, acetoxime, methyl ethyl ketone oxime and cyclohexane oxime, and sodium acid sulfite are included. These additives are usually used in an aqueous dispersion using a dispersant, and are added alone or in combination. The second processing agent is usually adjusted to contain 10 to 25 wt% of the total solid content.

The first treatment agent and the second treatment agent can be attached to the polyester fiber material by any method such as contact with a roller or application or dipping by spraying from a nozzle. Further, a pre-treated yarn to which a polyepoxide compound has been applied in advance in the yarn-making process may be used.

[0029] The amount of solids adhered to the polyester fiber is 0.1 to 10 wt%, preferably 0.5 to 5 wt% for the first treatment agent composition, and 0.5 to 5 wt% for the second treatment agent composition.
It is suitable to make the deposit 10 to 10 wt%, preferably 1 to 5 wt%. In order to control the amount of solids adhering to the fiber, means such as squeezing with a pressing roller, scraping with a scraper or the like, blowing off with air blowing, suction, and beating with a beater may be used.

In the present invention, after treating the polyester fiber with the first treating agent, the polyester fiber is dried at 50 to 180 ° C. for 0.5 to 5 minutes, preferably 1 to 3 minutes. Heat-treated at a temperature lower by 10 ° C, preferably at a temperature of 220 to 250 ° C for 0.5 to 5.0 minutes, preferably 1 to 3 minutes, and further, RF of the second treatment agent
L at a temperature of 80 to 180 ° C.
Minutes, preferably 1-3 minutes, then 150-2
60 ° C., preferably at a temperature of 220 to 250 ° C.
Heat-treat for 5.0 minutes, preferably 1-3 minutes.

If the heat treatment temperature is too low, the adhesion to rubbers becomes insufficient, while if the temperature is too high, the polyester fibers are melted and fused, become extremely hard, or deteriorate strongly, and cannot be put to practical use.

[0032]

The polyester fiber obtained by the present invention has a surface coated with a treating agent containing an epoxy group.
Furthermore, since it is coated with a treating agent containing polybutadiene rubber latex having an affinity for the ethylene propylene rubber as the adhered rubber, the affinity for the adhered rubber is high, and a polybutadiene rubber latex having a small average particle diameter is used. Since the fiber surface is covered, the cohesive force of the adhesive layer can be increased by the added crosslinking agent, which contributes to improvement of heat resistance and the like and expresses good adhesiveness.

Therefore, the polyester fiber obtained according to the present invention can sufficiently exhibit the excellent properties inherent in polyester fiber as a fiber for reinforcing rubber.

[0034]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to examples, but the present invention is not limited thereto. In addition, the evaluation method in an Example is as follows.

(1) Cord Peeling Adhesive Force A value representing the magnitude of the adhesive force between the treated cord and the rubber, 25 of the resulting treated cords are arranged in one inch and embedded in an ethylene-propylene-based unvulcanized rubber. , Surface pressure 5kg / c
After pre-pressing at m ² and a temperature of 80 ° C., it is covered with a polyester sheet and rubber so as not to be affected by moisture, and steam-vulcanized at 150 ° C. for 30 minutes. The force required to peel the cord from the rubber at a speed of 200 mm / min using the test piece is shown in kg / inch.

Example 1 A resorcinol-formalin initial condensate Sumikanol 700S (Sumitomo Chemical Co., Ltd., 65% aqueous solution) reacted with an acidic catalyst was added to water containing an aqueous solution of caustic soda and an aqueous solution of ammonia. Stir and disperse.

Next, Nippol 2518FS (a water emulsion of vinylpyridine / styrene / butadiene terpolymer manufactured by Zeon Corporation) and Nippol LX-111A2
(Nippon Zeon Co., Ltd., polybutadiene rubber latex 55% aqueous emulsion: average particle diameter 0.30 μm, maximum particle diameter 0.5 μm, particles having a particle diameter of 0.30 μm or less were measured by a sodium alginate method.) 96 cumulative%) and 1: 4 (vinyl pyridine / styrene / butadiene terpolymer / polybutadiene rubber latex) in a solid content ratio with the resorcinol / formalin initial condensation dispersion.
3: 7 (weight ratio)) and formalin with an R / F ratio of 1:
2 (molar ratio) and mix uniformly.

Next, Elastron B was added to the RFL mixture.
N-69 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., diphenylmethane diisocyanate methyl ethyl ketoxime block 33%
Aqueous dispersion) was added and mixed with RFL at a solid content ratio of 6: 1, and the mixture was aged at 20 ° C. for 24 hours.

Immediately before use, add Denabond E to the above mixture.
(A 20% solution of a special chlorophenol compound manufactured by Nagase Kasei Kogyo Co., Ltd.) was added to RFL at a solid content ratio of 2.5: 1, and the mixture was sufficiently stirred and used. Further, the control of the viscosity and the amount of adhesion of the treating agent was adjusted by adding and diluting water to the treating agent.

Next, a polyethylene terephthalate pretreated yarn (manufactured by Teijin Limited, [η] = 0.89, 150) to which a polyepoxide compound has been previously applied in the yarn making step.
A single filament (0 denier / 250 filaments) was twisted at 10 T / 10 cm to obtain a cord.

The cord was immersed in the above-mentioned treating agent using a computer treater (manufactured by CA Ritzler Co., Ltd., tire cord processor), dried at 170 ° C. for 2 minutes, and subsequently at 235 ° C. for 1 minute. Further, heat treatment was performed at 240 ° C. for 1 minute.

The solid content of the treating agent was adhered to the adhesive-treated polyester cord by 3.0 wt%. The obtained treated cord was vulcanized by the method described above, and the peel strength of the cord was measured. Table 1 shows the results.

The compounding composition of the rubber used in the evaluation is as follows. EPDM 100 parts HAF-carbon black 120 parts Process oil (paraffinic) 90 parts Zinc white 5 parts Stearic acid 3 parts Vulcanizing agent 3.5 parts Vulcanization accelerator 2.5 parts

[Examples 2 to 3] Processing and evaluation were performed in the same manner as in Example 1 except that the mixing ratio of the treating agent was variously changed. Table 1 shows the results.

Comparative Example 1 In Example 1, the polybutadiene rubber latex used as the treating agent was LX-111NF (manufactured by ZEON CORPORATION, polybutadiene rubber latex 55).
% Water emulsion: average particle diameter 0.35 μm, maximum particle diameter 1.
In the particle size distribution measurement by the sodium alginate method at 0 μm, the same treatment as in Example 1 was performed except that particles having a particle size of 0.30 μm or less were used (83 cumulative%). Table 1 shows the results.

[0046]

[Table 1]

Claims (1)

[Claims] 1. A method of treating a polyester fiber with a first treating agent containing a polyepoxide compound and then treating the polyester fiber with a treating agent containing a resorcinol-formalin rubber latex (RFL), a blocked polyisocyanate compound and a chlorophenol compound. A method for bonding polyester fibers, comprising using a polybutadiene rubber latex having a particle size distribution that simultaneously satisfies the following (a) to (c) in the particle size distribution measurement by the sodium alginate method as the latex. (A) Average particle size ≦ 0.30 μm (b) Maximum particle size ≦ 0.50 μm (c) 90% or more of particles having a particle size of 0.30 μm or less