JP3188639B2 - Processing method of polyester fiber for high pressure hose reinforcement - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite of a polyester fiber and a rubber, and more particularly, to a method of bonding a polyester fiber for a high-pressure hose having excellent adhesion to an ethylene propylene rubber (EPDM). Products to which the adhesive treatment method of the present invention can be applied include products such as rubber hoses, diaphragms, V-belts, and conveyor belts having a fiber reinforcing layer or a fiber base cloth, and those which are treated in a cord form. It is particularly useful for a polyester fiber for reinforcing a high-pressure rubber hose used for a flow path of a pressure fluid in which it is important that a void portion in a cord is small.

[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, the temperature of the engine room of an automobile increases, so that the rubber material is changing to one having excellent high-temperature characteristics. As one of them, there is an ethylene propylene rubber, but at present, it is not possible to obtain a satisfactory adhesive strength by the conventional method because the rubber has few double bonds in the chemical structure and has poor reactivity. . Further, when polyester fibers are bonded to ethylene propylene rubber, the polyester fibers are relatively inert, and the bonding with the rubber matrix is insufficient.
Therefore, a chemical treatment method using various chemicals, for example, a method of treating polyester fibers with a highly reactive chemical such as an epoxy compound or an isocyanate compound has been proposed (JP-A-54-77794, JP-A-54-77794). 60-99
076, JP-A-60-21924).

In high-pressure hose applications, various types of liquid as a pressurizing medium are prevented from penetrating from the end face of the hose into the reinforcing fiber layer in the hose fitting under the pressurizing condition at the time of using the hose. The pressure can be quickly transmitted at the same time as the life is greatly improved. For this purpose, it is important that the cord itself is used in a tight form. For example, a method in which the first treatment agent is treated in a yarn state (Japanese Patent Laid-Open No. Hei 7-138880) or a nip during immersion of the treatment agent is used. Method of nipping with a roller (JP-A-7-21
No. 6755) has been proposed. However, these methods have problems such as complicated processes.

[0004]

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 use a cord as a reinforcing fiber for a high-pressure hose made of an ethylene propylene rubber matrix. Provided is a method for treating polyester fibers that can be used in a tightly-closed form, has excellent adhesiveness with an ethylene propylene rubber matrix, and provides a flexible cord with excellent braidability in hose molding. It is in.

[0005]

According to the study of the present inventors, the object of the present invention is to provide a method for treating a polyester fiber with a first treating agent containing a polyepoxide compound, a blocked polyisocyanate compound and a polyurethane compound. ,
Next, resorcinol / formalin / rubber latex (RF
L) A method for treating a polyester fiber for reinforcing a high-pressure hose, comprising treating with a second treating agent containing a blocked polyisocyanate compound and a special chlorophenol compound. Is achieved.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The polyester fiber referred to in the present invention is a fiber comprising a polymer composed of an aromatic dicarboxylic acid component and a glycol component. In particular, ethylene glycol or tetramethylene glycol is used as a glycol component, and terephthalic acid is used. Polyester fibers containing polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polybutylene naphthalate, or the like containing an acid or naphthalene dicarboxylic acid as a main acid component are preferred. The single fiber fineness, the number of filaments, the cross-sectional shape, the fiber properties, the fine structure, the presence or absence of additives, and the polymer properties (average molecular weight, terminal carboxyl group concentration, etc.) of the polyester fiber are arbitrary and need not be particularly limited.

The polyepoxide compound contained in the first treating agent of the present invention is a compound containing at least two or more epoxy groups per molecule in an amount of 0.2 g equivalent or more per 100 g of the compound. For example, reaction products of polyhydric alcohols such as ethylene glycol, glycerol, sorbitol, pentaerythritol, and polyethylene glycol with halogen-containing epoxides such as epichlorohydrin, resorcinol, bis (4-hydroxyphenyl) dimethylmethane, phenol-formaldehyde resin A reaction product of a polyhydric phenol such as resorcinol-formaldehyde resin and the halogen-containing epoxide, a polyepoxide compound obtained by oxidizing an unsaturated compound with peracetic acid or hydrogen peroxide, and the like. 3,
4-epoxycyclohexene epoxide, 3,4-epoxycyclohexenemethyl-3,4-epoxycyclohexenecarboxylate, bis (3,4-epoxy-6
-Methyl-cyclohexylmethyl) adipate and the like. In particular, 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.

[0008] Such a polyepoxide compound is usually used as an emulsion. To prepare an emulsion or a solution, for example, such a polyepoxide compound as it is, or a solution obtained by dissolving the polyepoxide compound in a small amount of a solvent as necessary, is used as a known emulsifier, for example, sodium alkylbenzenesulfonate, dioctyl sulfosuccinate sodium salt, nonylphenol ethylene oxide. Emulsify or dissolve using adducts and the like.

The blocked polyisocyanate compound contained in the first treating agent is an addition-reactive product of the polyisocyanate compound and the blocking agent, and generates an active polyisocyanate compound by releasing a blocking component upon heating. Things.

Examples of the polyisocyanate compound include polyisocyanates such as tolylene diisocyanate, metaphenylene diisocyanate, diphenylmethane diisocyanate, hexamethylene diisocyanate, polymethylene polyphenyl polyisocyanate, and triphenylmethane triisocyanate, or these polyisocyanates and active hydrogen atoms. Having a terminal isocyanate group obtained by reacting a compound having two or more such as trimethylolpropane, pentaerythritol and the like with a molar ratio of isocyanate group (-NCO) to hydroxyl group (-OH) exceeding 1 Glycol adduct polyisocyanate and the like. 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 resorcinol; aromatic secondary amines such as diphenylamine and xylidine; lactams such as phthalimide, caprolactam and valerolactam; Oximes such as acetoxime, methyl ethyl ketone oxime and cyclohexane oxime, and sodium acid sulfite.

Above all, a water-soluble blocked polyisocyanate compound represented by the following general formula is preferred because it has high adhesiveness and good permeability between single yarns and film-forming property.

[0013]

Embedded image

A is a polymethylene condensate residue of phenyl isocyanate, X is a caprolactam residue, and Y is β
It is particularly preferred when the aminoethylsulfonic acid metal salt residue and B are ethylene oxide-added bisphenol residues.

Next, the polyurethane compound contained in the first treating agent of the present invention is a compound synthesized by a polyaddition reaction using polyisocyanate and polyol as main raw materials. The polyisocyanate may be any isocyanate compound such as an aromatic isocyanate represented by tolylene diisocyanate, an aliphatic isocyanate such as hexamethylene diisocyanate, and an alicyclic isocyanate. As the polyol, polyethylene glycol, polytetramethylene glycol, polyester-based polyol and the like are usually used. Furthermore, it is also possible to prepare a prepolymer using a suitable blocking agent at the terminal of the isocyanate component, and subsequently to apply heat to polymerize to form a polyurethane compound.

In particular, the average molecular weight is from 1,000 to 2,500
The water-soluble urethane prepolymer is preferable because the penetration of the treating agent between the single yarns is good. Further, an ester-based polyurethane compound is preferable in terms of adhesiveness.

The first treating agent of the present invention contains an epoxy compound (A), a blocked polyisocyanate compound (B) and a polyurethane compound (C).
(B), (C) The compounding weight ratio of each component is (A) / [(A)
+ (B)] is 0.06 to 0.3, (C) / [(A) +
(B)] is desirably used in a range of 0.2 to 7. In particular, (A) / [(A) + (B)] is 0.08 to
0.2, (C) / [(A) + (B)] is preferably blended in the range of 0.5 to 5.

If (A) / [(A) + (B)] is out of the above range, the rubber adhesion rate to the polyester fiber becomes poor, and the adhesiveness tends to decrease.
When [(A) + (B)] is smaller than the above range, the treated polyester fiber becomes hard and may cause a decrease in fatigue resistance. On the other hand, if it is larger than the above range, the adhesiveness decreases.

The total solid content including the epoxy compound, the blocked polyisocyanate compound and the polyurethane compound is 0.1 to 30% by weight, preferably 1 to 20% by weight.
Use it so that If the concentration is too high, the viscosity will also increase, making it difficult to control the amount of adhesion.

When the epoxy compound in the first treating agent is used as a water emulsion, an appropriate amount of an emulsifier, ie, a surfactant, is 25% by weight or less, preferably 15% by weight, based on the solid content.
% By weight or less, and if it exceeds the above range, the adhesiveness tends to slightly decrease.

Next, resorcinol-formalin rubber latex (RFL) contained in the second treating agent of the present invention is prepared by reacting resorcinol and formalin with an initial condensate (RF) obtained by reacting with an alkali or acidic catalyst. It is a mixture of rubber latex, and the effect can be obtained by applying any of the known techniques regarding the mixing ratio of resorcin, formalin, and rubber latex. Usually, the molar ratio of resorcin to formalin is from 1: 0.1 to 1: 8, preferably from 1: 0.5 to 1: 5. The amount of RF used varies depending on the amount of the special chlorophenol compound to be described later, but usually, the total amount of the RF and the special chlorophenol compound and the rubber latex are 1: 1 to 1: 1 in terms of solids weight ratio.
5, preferably 1: 3 to 1:12. If the compounding ratio of the rubber latex is too small, the polyester fiber after the treatment becomes hard and the fatigue resistance tends to decrease, and if it is too large, the adhesive performance tends to decrease.

The rubber latex used here includes, for example, natural rubber latex, polybutadiene latex, styrene / butadiene copolymer rubber latex, vinyl pyridine / styrene / butadiene terpolymer latex, and these may be used alone or in combination. I do. Among them, vinyl pyridine / styrene / butadiene terpolymer latex or polybutadiene latex is used alone, or when these are used in combination, especially when used in a ratio of 7: 3 to 3: 7, it shows excellent performance. .

The special chlorophenol compound contained in the second treating agent is a chlorophenol, preferably a chlorophenol / resorcin / formalin cocondensate obtained by cocondensing parachlorophenol and resorcin with formaldehyde. However, those having a trinuclear body (I), a pentanuclear body (II), and a heptanuclear body (III) represented by the following structural formula (Chemical Formula 4) as a main component are preferable.
At 0% by weight, the viscosity of the alkaline aqueous solution of PH10 is 70-
Those within the range of 150 centipoise are preferred.

[0024]

Embedded image

The mixing ratio of the special chlorophenol compound and the resorcinol-formalin rubber latex varies slightly depending on the compounding of the rubber to be adhered, but in general, the ratio of RFL / special chlorophenol compound is 50/50 to 80/20.
The range of (solid content weight ratio) is appropriate. In addition, the aforementioned RF
Usually, the ratio of the former to the latter is preferably in the range of 3/1 to 1/1.

Next, as the blocked polyisocyanate compound contained in the second treating agent, the same blocked polyisocyanate compound as described in the first treating agent may be used. The amount of such a blocked polyisocyanate compound to be added to the second treating agent varies depending on the type and the composition of the rubber to be adhered, but is usually 5 to 40% by weight, preferably 10 to 10% by weight based on the above-mentioned RFL solid content. -20% by weight is suitable. The above-mentioned second processing agent usually has a total solid content of 10 to 10.
It is adjusted to contain 25% by weight.

In order to apply the first and second treating agents to the polyester fiber material, an arbitrary method such as application by contact with a roller or spraying from a nozzle, or immersion in the treating agent may be employed. Can be. The solid content attached to the polyester fiber is 0.1 to 10% by weight, preferably 0.5 to 5% by weight as the first processing agent solid content, and 0.5 to 10% by weight, preferably 0.5 to 10% by weight as the second processing agent solid content. It is preferred that 1 to 5% by weight be adhered. 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 the polyester fiber is treated with the first treating agent, it is dried at 50 to 180 ° C. for 0.5 to 5 minutes, preferably 1 to 3 minutes, and then dried at 180 ° C. to the melting point of the polyester fiber. At a temperature of 10 ° C. lower, preferably at a temperature of 200 to 240 ° C. for 0.5 to 5.0 minutes,
Preferably, heat treatment is carried out for 1 to 3 minutes, and after treatment with a treatment agent containing RFL as a second treatment agent, 0.5 to 80 ° C. to 180 ° C.
Dry for ~ 5 minutes, preferably 1-3 minutes, then 150
At a temperature of -260C, preferably 220-250C.
Heat treatment is performed for 5 to 5.0 minutes, preferably 1 to 3 minutes. If the heat treatment temperature is too low, adhesion with rubbers becomes insufficient,
On the other hand, if the temperature is too high, the polyester fiber melts and fuses, or becomes extremely hard, or is strongly deteriorated, and cannot be put to practical use.

[0029]

EXAMPLES The present invention will now be described more specifically with reference to examples, but the present invention is not limited thereto. The evaluation items in the examples were in accordance with the following methods.

<AD property (air diffusion property)> Four cords are placed in a rubber bundle and vulcanized.
Cord bundle (1500) exposed at the end face of the vulcanizing block
(Denier × 4 pieces), air was flowed at a pressure of ² kg / cm ² for 5 minutes, and the amount of air permeated at that time was calculated from the change in water column pressure. The AD property evaluates the air permeability of the hose blade layer, that is, the degree to which air passes through a gap in the cord.

<Cord hardness> Measured according to the Gurley method. The larger this value is, the harder it is.

<Peeling Adhesive Strength> The hose was cut to a length of 1 inch, and the peeling strength when the rubber on the outside was peeled along the circumference of the hose was measured.

<Rubber Adhesion Rate> In the above-mentioned measurement of peel adhesion, the remaining adhesion rate of rubber on the blade cord after the outer rubber was peeled was determined.

Examples 1-3 and Comparative Examples 1-3 Neocor SW-30 (Daiichi Kogyo Seiyaku Co., Ltd.) was used as a surfactant in Denacol EX-611 (sorbitol polyglycidyl ether, manufactured by Nagase Kasei Kogyo Co., Ltd.). Co., Ltd., 30% by weight of dioctyl sulfosuccinate sodium salt solution) at a solid content ratio of 25% by weight, and uniformly dissolve in about 30 times the water with stirring. Then, Elastron BN-04 (a 33% by weight aqueous solution of a water-soluble blocked polyisocyanate compound manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) was mixed with the epoxy at a solid content ratio of 1: 8, and Elastron E-37 (Daiichi Kogyo Seiyaku Co., Ltd.) ), A water-soluble urethane compound (25% by weight aqueous solution) was also added at a ratio of 1:12, and the mixture was uniformly mixed. The resulting mixture was adjusted to a concentration of 5% by weight to obtain a first treating agent.

On the other hand, resorcinol reacted with water containing an aqueous solution of caustic soda and aqueous ammonia with an acidic catalyst.
A formalin precondensate, Sumikanol 700S (manufactured by Sumitomo Chemical Co., Ltd., 65% by weight aqueous solution) is added and sufficiently stirred and dispersed. Next, Nippol 2518FS (vinyl styrene / styrene / butadiene terpolymer 40% by weight water emulsion manufactured by Zeon Corporation) and Nippol LX-
111 NF (Polybutadiene rubber latex 55% by weight water emulsion manufactured by ZEON CORPORATION) was
The formalin initial condensation dispersion liquid and the solid content ratio were 1: 4 (vinyl pyridine / styrene / butadiene terpolymer / polybutadiene rubber latex = 3: 7 (weight ratio)), and the R / F ratio of formalin was 1: 2 (molar ratio). ) And mix uniformly. Next, Elastron BN-69 (manufactured by Daiichi Kogyo Seiyaku Co., Ltd., diphenylmethane diisocyanate methyl ethyl ketoxime block 33% by weight aqueous dispersion) was added to the RFL mixture as a solid content ratio of RF.
The mixture added and mixed so that L / blocked polyisocyanate = 1/6 was aged at 20 ° C. for 24 hours.
Immediately before use, Denabond E (a 20 wt% solution of a special chlorophenol compound manufactured by Nagase Kasei Kogyo Co., Ltd.) is added so that the solid content ratio becomes RF / special chlorophenol compound = 2/1, and the concentration is adjusted to 15%. Adjusted to obtain a second treating agent.

Polyethylene terephthalate fiber (manufactured by Teijin Limited, intrinsic viscosity 0.89, 1500 denier / 25)
0 filament) at 10T /
The cord was twisted at 10 cm to obtain a cord.

The cord was immersed in the first treating agent using a computer treating machine (tire cord treating machine manufactured by CA Ritzler Co., Ltd.), dried at 130 ° C. for 2 minutes, and subsequently at 230 ° C. Heat treat for 1 minute. Next, after being immersed in the second treatment agent, it is dried at 170 ° C. for 2 minutes, and then heat-treated at 240 ° C. for 1 minute. The solid content of the first treating agent and the solid content of the second treating agent were adhered to the treated polyester cord by 1.0% by weight and 2.0% by weight, respectively.

The obtained treated cord was braided at a crossing angle of 108 °, formed into a hose using ethylene propylene-based unvulcanized rubber, and subjected to steam vulcanization at 150 ° C. for 40 minutes. The compounding composition of the rubber used is as follows. EPDM 100 parts HAF-carbon black 120 parts Process oil (paraffin type) 90 parts Zinc white 5 parts Stearic acid 3 parts Vulcanizing agent 3.5 parts Vulcanization accelerator 2.5 parts The evaluation results are shown in Table 1. Examples 2 to 3 and Comparative Examples 1 to 3 were the same as Example 1 except that the mixing ratio of the polyepoxide compound, the blocked polyisocyanate compound and the polyurethane compound in the first treating agent was changed as shown in Table 1. I did the same. The results are shown in Table 1.

[0039]

[Table 1]

As is apparent from Table 1, according to the present invention, AD properties, adhesive properties and cord hardness are good in a well-balanced manner.

[0041]

According to the treatment method of the present invention, the polyester fiber can have a tight form by being coated with the first treatment agent which is soft and has a high film-forming property penetrating into the spaces between the single yarns. Further, the fiber surface is coated with the first treating agent containing an epoxy group, and then the second treating agent is formed of a special chlorophenol compound containing a halogen having a high affinity with the ethylene propylene rubber as the adhered rubber. First, in the first treating agent, the bonding between the polyester fiber and the adhesive layer is firmly performed, and the treating agent penetrates into the space between the single yarns to form a strong film. Since the voids are reduced and the second processing agent is treated thereon, the air diffusion property can be reduced, and a cord having good adhesiveness to rubber can be obtained.

Further, the film formed by the first treating agent is flexible because the polyurethane compound is used, and the obtained cord is also very flexible. For example, uniform braiding can be performed at the time of forming a hose in a high pressure hose application. Also, the gap between the bladed cords can be reduced. Therefore, according to the present invention, it is possible to prevent various liquids as a pressurized medium from penetrating into the reinforcing fiber layer from the hose end face in the hose fitting portion under the pressurized condition when the hose is used,
A treatment cord suitable for reinforcing a high-pressure hose, which can greatly improve the life of the hose and can quickly transmit pressure and the like, can be obtained.

──────────────────────────────────────────────────続 き Continuation of front page (56) References JP-A-7-238473 (JP, A) JP-A-57-51877 (JP, A) JP-A-7-216755 (JP, A) JP-A 63-238755 126973 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) D06M 15/00-15/715

Claims (4)

(57) [Claims] 1. A polyester fiber treated with a first treating agent containing a polyepoxide compound, a blocked polyisocyanate compound and a polyurethane compound, and then resorcinol-formalin rubber latex (RFL), a blocked polyisocyanate compound and a special chlorophenol compound A method for treating polyester fibers for reinforcing high-pressure hoses, characterized by treating with a second treating agent containing: 2. The method according to claim 1, wherein the polyurethane compound contained in the first treating agent is a water-soluble urethane prepolymer compound having an average molecular weight of 1,000 to 2,500. 3. The high pressure hose reinforcement according to claim 1, wherein the blocked polyisocyanate compound contained in the first treating agent is a water-soluble blocked polyisocyanate compound represented by the following general formula (Formula 1). Processing method of polyester fiber. Embedded image 4. The special chlorophenol compound contained in the second treating agent is a compound obtained by co-condensing parachlorophenol, resorcin and formaldehyde, and is a trinuclear compound represented by the following structural formula (Formula 2). (I), pentanuclear (II), 7
Containing nucleus (III) as a main component and having a solid content of 20
The viscosity of the aqueous alkali solution of PH10 is 70 to 15% by weight.
The method for treating a polyester fiber for reinforcing a high-pressure hose according to claim 1, wherein the pressure is 0 centipoise. Embedded image