JPH05185136A - Surface treatment of steel wire - Google Patents

Abstract

PURPOSE:To improve corrosion resistance and adhesion to rubber by effectively treating the surface of the steel wire by a triazine thiol deriv. CONSTITUTION:A soln. prepd. by dissolving the 1, 3, 5-triazine2, 4, 6-trithiol or 6-dibutyl amino-1, 3, 5-triazine-2, 4-dithiol expressed by 'formula' into triethanol amine is added to the lubricant of an emulsion type. The steel wire is drawn and is subjected to a surface treatment in the lubricant.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface treatment method for steel wires used as a reinforcing material for rubber.

[0002]

2. Description of the Related Art Conventionally, steel wires used for reinforcing tires for automobiles, hose reinforcing hose wires, conveyor belt reinforcing belt cords, timing belt reinforcing timing belt cords, escalator reinforcing steel cords are made of rubber. The surface is brass-plated to adhere with. However, simple brass plating is not sufficient for corrosion resistance, adhesion stability, wet adhesion, and heat resistance. In order to solve these problems, various kinds of binary plating, ternary plating, quaternary plating, etc. have been studied. However, all the above-mentioned problems have not been solved yet, and moreover, the manufacturing process is further complicated and the cost is significantly increased.

On the other hand, it is known that treating the surface of a metal with a triazine thiol derivative can improve the corrosion resistance of the metal and the adhesiveness to rubber (for example, Kunio Mori: Practical Metal Surface Technology, 37, 373 (1989)). Japanese Patent Publication No. 60-41084; Japanese Patent Laid-Open No. 58-87034.
Publication). In these known techniques, a metal is immersed in a solution in which a triazine thiol derivative is dissolved in water or an organic solvent so that the triazine thiol derivative is adsorbed on the surface of the metal for surface treatment. However, in this method, the dipping treatment process requires a relatively high temperature and a long treatment time. Further, since the adsorption layer of the triazine thiol derivative formed on the metal surface by the dipping treatment lacks the denseness, the heat resistance, water resistance, and steam resistance of the wire rubber adhesive composite material produced using this are Fatigue resistance cannot be said to be sufficient. Furthermore, since this method is a batch process, it was not suitable for industrially treating a large amount of steel wire.

Therefore, the present inventors have filed Japanese Patent Application No. 1-313.
No. 54 disclosed a method of wire-drawing and surface-treating a steel wire in a lubricant containing a triazine thiol derivative.

[0005]

However, even if the triazine thiol derivative is added to the lubricant, the solubility of the triazine thiol derivative is limited, and most of them are in a suspended state. For this reason, even if the steel wire is drawn in such a lubricant, the surface treatment cannot be effectively performed.

An object of the present invention is to provide a method capable of effectively treating the surface of a steel wire with a triazine thiol derivative, and to improve the corrosion resistance and the adhesion with rubber.

[0007]

The surface treatment method for a steel wire according to the present invention comprises adding a solution of a triazinethiol derivative dissolved in ethanolamine to a lubricant and wire-drawing the steel wire in the lubricant. It is characterized in that the surface treatment is performed together with.

In the present invention, as the steel wire, a bare steel wire which is not plated, a copper-plated steel wire, a brass-plated steel wire, a nickel-plated steel wire, a tin-plated steel wire, a zinc-plated steel wire, a copper-tin-plated Steel wire, cobalt plated steel wire, etc. are used.
When using a plated steel wire, the plating thickness before wire drawing is usually 10 to 1000 nm, and further 150 to 4 nm.
It is preferably 00 nm. The plating amount is usually 0.1 to 40 g / kg, preferably 0.5 to 10 g / kg.

In the present invention, the triazine thiol derivative is represented by the following general formula

[0010]

[Chemical 1] (In the above formula, R is -OR ', -SR', -NHR ',-
N (R ′) ₂ ; R ′ is H, an alkyl group, an alkenyl group,
Phenyl group, phenylalkyl group, alkylphenyl group, or cycloalkyl group, M is H, Na, Li, K,
1 / 2Mg, 1 / 2Ba, 1 / 2Ca, aliphatic first grade, 2
Primary or tertiary amine, quaternary ammonium salt, or phosphonium salt).

Specific examples of the triazine thiol derivative used in the present invention include the following. For example, 1,3,5-triazine-2,4,6
-Trithiol (F), 1,3,5-triazine-2,
4,6-trithiol monosodium (FMN),
1,3,5-triazine-2,4,6-trithiol
Monopotassium, 1,3,5-triazine-2,4,6-
Trithiol monoethanolamine (FME), 1,
3,5-triazine-2,4,6-trithiol diethanolamine (FDE), 1,3,5-triazine-
2,4,6-Trithiol triethylamine (FT
EA), 1,3,5-triazine-2,4,6-trithiol octylamine, 1,3,5-triazine-
2,4,6-trithiol tetrabutylammonium salt, 1,3,5-triazine-2,4,6-trithiol bis (tetrabutylammonium salt) (F2A),
6-anilino-1,3,5-triazine-2,4-dithiol (AF), 6-anilino-1,3,5-triazine-2,4-dithiol monosodium (AMN),
6-anilino-1,3,5-triazine-2,4-dithiol triethylamine, 6-dibutylamino-1,
3,5-triazine-2,4-dithiol (DB), 6
-Dibutylamino-1,3,5-triazine-2,4-
Dithiol monosodium (DBMN), 6-dibutylamino-1,3,5-triazine-2,4-dithiol monoethanolamine (DBME), 6-dibutylamino-1,3,5-triazine-2,4 -Dithiol-ethylamine, 6-dibutylamino-1,3,5-triazine-2,4-dithiol-triethylamine, 6
-Dibutylamino-1,3,5-triazine-2,4-
Dithiol butylamine (DBB), 6-dibutylamino-1,3,5-triazine-2,4-dithiol
Tetrabutylammonium salt (DBA), 6-dibutylamino-1,3,5-triazine-2,4-dithiol / tetrabutylphosphonium salt, 6-diallylamino-
1,3,5-triazine-2,4-dithiol, 6-diallylamino-1,3,5-triazine-2,4-dithiol monosodium (DAMN), 6-diallylamino-1,3,5- Triazine-2,4-dithiol
Monoethanolamine (DAME), 6-diallylamino-1,3,5-triazine-2,4-dithiol-butylamine, 6-diallylamino-1,3,5-triazine-2,4-dithiol-ethylenediamine, 6 -Diallylamino-1,3,5-triazine-2,4-dithiol / ethylenetriamine, 6-octylamino-
1,3,5-triazine-2,4-dithiol, 6-octylamino-1,3,5-triazine-2,4-dithiol monosodium and the like. One or more of these are used.

The lubricant used in this method is of the so-called emulsion type. This lubricant is composed of an emulsion in which an extreme pressure inhibitor, an oiliness agent, an emulsifier, a foaming inhibitor and the like are dispersed in a solvent. As the solvent, neutral or alkaline water or glycol (for example, ethylene glycol derivative, polyethylene glycol or diglyme) is used. In addition to the above components, for example, an anticorrosive agent or an antiseptic / antifungal agent may be contained.

The extreme pressure preventive agent has a function of preventing seizure of the wire during wire drawing. Examples of extreme pressure inhibitors include ethylenediamine phosphate, ethylenetriamine phosphate, pentaethylenetetramine phosphate, propylenediamine phosphate, butylenediamine phosphate, butylamine phosphate, octylamine phosphate,
Oleylamine phosphate, fatty acid ester / ethylenoxide adduct, phosphoric acid methyl ester / propylenoxide adduct, phosphoric acid butyl ester / proprenenoxide adduct, phosphoric acid octyl ester / proprenenoxide adduct, phosphoric acid oleyl ester / proprenenoxide adduct, etc. Can be mentioned. One or more of these are used. The extreme pressure inhibitor content in the lubricant (undiluted) is preferably 0.1 to 15% by weight, more preferably 1 to 10% by weight.

The oiliness agent has a function of preventing seizure of the wire during wire drawing and improving the wettability of the lubricant. As the oiliness agent, an amine salt of fatty acid is generally used. For example, acetic acid / octylamine, stearic acid /
Ethanolamine, stearic acid / diethanolamine, octylic acid / diethanolamine, linolenic acid / diethanolamine, oleic acid / diethanolamine,
Examples include oleic acid and butylamine. Further, as an oily agent, a reaction product of a fatty acid and an epoxy compound (eg, tetraethylene glycol oleate, pentaethylene glycol octylate, nonaethylene glycol stearate, decaethylene glycol erucate, decaethylene glycol linoleate, etc.); Reaction products of fatty acid esters and epoxy compounds (eg, butanediol octylate tetraethylene glycol, butanediol oleate hexaethylene glycol, butanediol stearate pentaethylene glycol, caproic acid butanediol ester pentaethylene glycol, caproic acid) Hexanediol ester pentaethylene glycol, etc.). These are used alone or in combination of two or more. The content of the oily agent in the lubricant (undiluted) is preferably 0.1 to 20% by weight, more preferably 1 to 15% by weight.

The emulsifier has a function of emulsifying the extreme pressure inhibitor, the oiliness agent, the foaming inhibitor and the like in water. As the emulsifier, a reaction product of an alkylamine and an epoxy compound is generally used. Examples thereof include octylamine tetraethylene glycol, dodecylamine decaethylene glycol, oleylamine decaethylene glycol, stearylamine octaethylene glycol and the like. The content of the emulsifier in the lubricant (undiluted) is 0.1
It is preferably 10 to 10% by weight, more preferably 0.5 to 5% by weight.

The foaming inhibitor has an action of suppressing foaming of the emulsion. As the foaming inhibitor, for example, mineral spirits such as decane, octane, hexadecane, heptadecane, nonadecane are used. The content of the foaming inhibitor in the lubricant (undiluted) is 0.1 to 1
It is preferably 0% by weight, more preferably 0.5 to 5% by weight.

The rust preventive agent has a function of preventing corrosion of iron and brass components of the steel wire. Examples of the rust preventive agent include methyl paraoxybenzoate, bisphenol A, benzotriazole, and methylbenzotriazole. However, since the triazine thiol derivative also has a rust preventive effect, it is not always necessary to add the above-mentioned rust preventive agent. The content of the rust preventive in the lubricant (undiluted) is preferably 0.01 to 5% by weight, more preferably 0.1 to 1% by weight.

The antiseptic / antifungal agent has a function of preventing contamination of the lubricant by microorganisms. Examples of the antiseptic / antifungal agent include 1,2-benzisothiazolin-3-one, chlorinated phenol, formaldehyde, and formaldehyde releasing agent. However, since the triazine thiol derivative also has an antiseptic / antifungal action, it is not always necessary to add the antiseptic / antifungal agent described above. The content of the antiseptic / antifungal agent in the lubricant (undiluted) is 0.01 to 5% by weight, and further 0.1 to 1%.
It is preferably in the weight%.

In the present invention, the triazine thiol derivative is dissolved in triethanolamine (TEA) which has been heated to about 100 ° C. in advance. The solubility limit of the triazine thiol derivative in triethanolamine is about 50% by weight.
Is. This solution is added to the lubricant. As a result, the triazine thiol derivative is completely dissolved in the lubricant. Therefore, the concentration of the triazine thiol derivative in the lubricant can be made higher than before.
This lubricant can be used as is during processing, or
It is used by diluting it within 0 times, preferably 5 to 10 times.

In the present invention, the drawing of the steel wire is performed by using a wet type wire drawing machine. That is, a die is attached to a lubricating bath of a wet wire drawing machine, the above-mentioned lubricant is contained therein, and a steel wire having a diameter of, for example, 0.1 to 10 mm, preferably 1 to 4 mm is placed in the die for 1 to 2000 m.
The wire is drawn at a speed of 1 / min to a diameter of 0.01 to 5 mm, preferably 0.1 to 1 mm. Generally, in the case of a hard steel wire such as a bare steel wire or a nickel-plated steel wire, the wire is drawn at a low speed and the degree of wire drawing is low. On the other hand, in the case of a soft steel wire such as a copper-plated steel wire or a brass-plated steel wire (copper content rate in plating is 65% or more), high-speed wire drawing is possible,
The degree of wire drawing can also be increased. Therefore, the optimum values of the wire drawing speed and the wire drawing work ratio naturally vary depending on the type of steel wire.

By the above wire drawing operation, the coating layer containing the polymer of the triazine thiol derivative is formed on the surface of the steel wire. The mechanism by which this coating layer is formed is presumed to be as follows. When the steel wire comes into contact with the lubricant, the triazine thiol derivative is adsorbed on the wire surface. This state is considered to be the same as the state in which the triazine thiol derivative is adsorbed on the wire surface by the conventional dipping method. During the subsequent wire drawing process, the wire surface becomes an active metal surface. Also,
The triazine thiol derivative on the surface of the wire is exposed to high temperature and high pressure for a moment. For example, when a brass-plated steel wire is drawn at a drawing pressure of 100 kgf / mm ² , the surface temperature is said to reach several hundred degrees Celsius. As a result, a coating layer containing the polymer of the triazine thiol derivative is formed.

It has been confirmed by gel permeation chromatography that the coating layer contains a polymer. Also, by analysis such as infrared spectroscopy,
It has been confirmed that this coating layer contains a disulfide group, a thiol group, an unsaturated group and the like. This coating layer
Since it is dense and strong, it improves the corrosion resistance of the steel wire, and since it contains a disulfide group, it reacts with the components in the rubber to improve the adhesion between the two. Of the above-mentioned triazine thiol derivatives, for example, F or DAN is effective in improving the adhesion of the steel wire to rubber, and DB is effective in improving the corrosion resistance of the steel wire. Therefore, a plurality of triazine thiol derivatives may be appropriately mixed and used.

The steel wire having the coating layer containing the polymer of the triazine thiol derivative formed on the surface by performing the surface treatment at the same time as the wire drawing treatment as described above is used as a single wire or as a cord by twisting. .. There are various methods of twisting, but the method generally used at present (eg, Setsuo Fukuhara; Textile and Industry, 40,
No. 11, 627 (1984)) are all applicable.

These steel wires or steel cords obtained by twisting the steel wires are bonded to a rubber compound,
For example steel radial tires, steel wire reinforced conveyor belts, steel wire reinforced timing belts,
Products such as steel wire reinforced hoses and steel wire reinforced handrails are manufactured.

The composition of the rubber compound is not particularly limited. As the rubber compound, one containing each component of rubber, a filler, a softening agent, a vulcanizing agent, a vulcanization accelerator, and a vulcanization acceleration aid is used. Further, the rubber compound may contain components such as a lubricant, a stabilizer, and an adhesion aid (adhesion promoter) in addition to the above components.

As the rubber, various natural rubber (NR), isoprene rubber, butadiene rubber (BR), solution-polymerized butadiene rubber, solution-polymerized styrene-butadiene copolymer rubber (SBR), acrylonitrile-butadiene copolymer rubber (NBR), Ethylene-propylene copolymer rubber, ethylene-propylene terpolymer rubber (EPDM), silicone rubber, butyl rubber, chlorinated butyl rubber, brominated butyl rubber, chloroprene rubber, fluororubber, hydrin rubber,
Epichlorohydrin-ethylene oxide copolymer rubber,
Epichlorohydrin-ethylene oxide-allyl glycidyl ether terpolymer rubber, epichlorohydrin-
Propylene oxide-allyl glycidyl ether terpolymer rubber, chlorinated polyethylene rubber, acrylic rubber and its copolymer rubber (chlorine, epoxy, unsaturated), ethylene-vinyl acetate-acrylic ester terpolymer rubber, Urethane rubber etc. can be mentioned.

The filler is added for the purpose of increasing the amount and reinforcing.
Examples of the filler include carbon black, carbon black for rubber reinforcement, white carbon, hard clay,
Examples include calcium carbonate and silicate. The compounding amount of the filler is 5 to 200 parts by weight with respect to 100 parts by weight of rubber,
It is preferably 30 to 100 parts by weight.

The softening agent is added to improve the processability and moldability of rubber. Examples of the softening agent include phthalate ester plasticizers such as dioctyl phthalate (DOP) and dibutyl phthalate; fatty acid ester plasticizers such as dioctyl adipate and dioctyl sebacate;
Examples thereof include phosphoric acid ester plasticizers such as triphenyl phosphoric acid ester and tricresyl phosphoric acid ester; chlorinated paraffin, process oil, naphthene oil and the like. The compounding amount of the softening agent is 10 with respect to 100 parts by weight of rubber.
It is 0 part by weight or less, preferably 5 to 50 parts by weight.

The vulcanizing agent is blended to exert the elasticity of rubber. The vulcanizing agent used varies depending on the type of rubber, but the main ones are as follows.
For example, sulfur, dicumyl peroxide, 1,1-bis (t-butylperoxy) -3,3,5-trimethylcyclohexane, α, α′-bis (t-butylperoxyisopropyl) benzene, 2,5-dimethyl- 2,5-
Di (t-butylperoxy) hexane, 2,5-dimethyl-2,5-di (t-butylperoxy) hexyne-
3,1,3,5-triazine-2,4,6-trithiol, 6-butylamino-1,3,5-triazine-2,
4-dithiol, ethylene thiourea, hexamethylene diamine, ammonium benzoate, bisphenol A and the like. The compounding amount of the vulcanizing agent varies depending on the individual rubber, and therefore cannot be unconditionally limited, but generally, 0.1 to 10 parts by weight is suitable for 100 parts by weight of the rubber. For example, the amount of sulfur added is 0.5 with respect to 100 parts by weight of rubber.
It is preferably 10 to 10 parts by weight, more preferably 2 to 6 parts by weight. If the amount of sulfur is less than 0.5 part by weight, the rubber will be insufficiently vulcanized and the adhesion to the steel wire will be weak. 10 sulfur
If it exceeds the weight part, the heat resistance of the rubber and the water resistance of the composite material are significantly impaired.

The vulcanization accelerator and the vulcanization acceleration aid are blended in order to accelerate the action of the vulcanization agent. As a vulcanization accelerator,
For example, 2-mercaptobenzothiazole (M), 2-
Thiazole-based accelerators such as (4-morpholinyldithio) benzothiazole and dibenzothiazyl disulfide (DM); N-cyclohexyl-2-benzothiazyl sulfenamide (CBS), N-oxydiethylene- 2-
Benzothiazyl sulfenamide, N, N-dicyclohexyl-2-benzothiazyl sulfenamide, Nt
-Sulfenamide-based accelerators such as butyl-2-benzothiazyl sulfenamide, etc .; Churam-based accelerators such as tetramethylthiuram monosulfide, tetramethylthiuram disulfide, tetrabutylthiuram disulfide; fatty acid amines Quaternary ammonium salt,
Examples include polyfunctional monomers such as organic phosphonium salts, triallyl isocyanurate, trimethylolpropane triacrylate, and diallyl phthalate. As the vulcanization acceleration aid, ZnO, MgO, BaO, Ca (OH) ₂
And so on. These may be used alone or in combination of two or more.

The compounding amount of the vulcanization accelerator and the vulcanization acceleration aid varies depending on the types of the rubber and the vulcanizing agent, and therefore cannot be unconditionally limited, but it is generally 0.1 per 100 parts by weight of the rubber.
-20 parts by weight is suitable.

In order to produce a steel wire-rubber adhesive composite, it is preferable that at least each of the above components is contained in the rubber compound. Further, the following components such as a lubricant, a stabilizer, and an adhesion aid are not necessarily required to obtain a steel wire-rubber adhesive composite,
The inclusion of these components is advantageous for improving the water resistance, heat resistance, steam resistance and fatigue resistance of the steel wire-rubber adhesive composite.

Lubricants are added to improve the flow of the rubber compound during adhesive compounding. As the lubricant, for example, stearic acid, Na salt of stearic acid, Mg salt, C
Examples thereof include a salt, Ba salt or Zn salt, ethylene bisamide stearate, ethylene bisamide erucate, and paraffin wax. Lubricants are generally rubber 1
0.1 to 5 parts by weight is blended with respect to 00 parts by weight.

Stabilizers are included to prevent degradation of the adhesive composite. Examples of the stabilizer include a phenylenediamine-based antioxidant, a phenol-based antioxidant, nickel dithiocarbamate, and benzophenone. Stabilizers are generally 0.1% based on 100 parts by weight of rubber.
1 to 5 parts by weight is blended.

Examples of the adhesion aid include 1,3,5-triazine-2,4,6-trithiol, 6-butylamino-1,3,5-triazine-2,4-dithiol, 6
-Diallylamino-1,3,5-triazine-2,4-
Dithiol, cobalt naphthenate, cobalt stearate, aminobenzoic acid metal salt (Co, Mn, Zn, Mo,
Cr), resorcin, cresol, resorcin-formalin latex, resole-type phenol resin (including uncured one), formalin-alkylphenol resin, formalin-cresol resin (including uncured one), monomethylol melamine, dimethylol melamine , Trimethylolmelamine, hexamethylolmelamine, monomethoxymethylolmelamine, tetramethoxymethylolmelamine, pentamethoxymethylolmelamine, monomethylolurea, trimethylolurea, trimethoxymethylolurea, ethylenemaleimide, butylenemaleimide, phenylenemaleimide, abietic acid metal salt (Co, Ni, Fe, Mn) and the like. The adhesion aid is 0.1 to 20 parts by weight with respect to 100 parts by weight of rubber,
Preferably 0.5 to 5 parts by weight is blended.

The steel wire-rubber-bonded composite material of the present invention is obtained by bringing a surface-treated steel wire (cord) into contact with a rubber compound, hot pressing or steam heating to simultaneously compound the rubber and vulcanize it. Manufactured by. The condition of this step is usually 80 to 230 ° C., preferably 130 to 180 ° C., and 5 to 180 minutes, preferably 10 to 60 minutes. Note that post-crosslinking may be further performed depending on the type of rubber or vulcanizing agent.

[0037]

EXAMPLES Examples of the present invention will be described below.

Example 1 4 parts by weight of ethylenediamine phosphate, 8 parts by weight of oleic acid triethanolamine salt, 4 parts by weight of laurylamine octaethylene glycol, 3 parts by weight of octadecane, 2 parts by weight of tetraethylene glycol octylate, dodecylphosphoric acid 0.5 parts by weight of methyl butanediol ester pentapropylene glycol paraoxybenzoate, 1 part by weight of methylbenzotriazole, and 0.5 parts by weight of 1,2-benzisothiazolin-3-one were dispersed in 72.5 parts by weight of water. A lubricant has been prepared.

Triethanolamine was heated to 100 ° C. to give 1,3,5-triazine-2,4,6-trithiol (F) or 6-dibutylamino-1,3,5-triazine-2,4-dithiol. (DB) was added and dissolved to be 50% by weight. This solution was added to the lubricant so that the concentration of F or DB was 3, 5 or 10% by weight. In the lubricant, F or DB was in a completely dissolved state (lubricant of the present invention).

For comparison, the lubricant is F or DB.
Powder was added to give a concentration of 3, 5 or 10% by weight. In this case, F or DB was in a suspended state in the lubricant (conventional lubricant).

Using these two kinds of triazine thiol derivative-containing lubricants, a brass-plated steel wire having a diameter of 1.40 mm was drawn to obtain a wire having a diameter of 0.60 mm. The number of dies used was 10, and the wire drawing speed was 700 m / min.

With respect to the steel wire after being respectively drawn with two kinds of lubricants, ESCA was used to measure how much sulfur, which is the main element of the triazine thiol derivative, was introduced into the plating as a result of the reaction. ..
It should be noted that, in order to eliminate the influence of stains on the plated surface, measurement was performed by sputtering to a depth of about 1 nm by an argon ion sputtering method. Figure 1 shows the result when F is used.
2 shows the results when the DB is used.

As a method of analyzing the reaction amount of the triazine thiol derivative, there are a silver nitrate titration method, a high-frequency plasma emission analysis method, etc. in addition to ESCA.

From FIGS. 1 and 2, it was confirmed that the amount of the triazine thiol derivative that penetrated in the depth direction of the brass plating was larger in the case of using the lubricant of the present invention than in the case of the conventional lubricant. Was done. It is considered that F has a larger reaction amount than DB because F has a smaller molecular weight and easily penetrates into the plating.

Example 2 A steel cord strand was trial-produced on a steel tire cord actual process line. Instead of the lubricant used in the actual process, the lubricant of the present invention or the lubricant of the conventional lubricant (the triazine thiol concentration is 3, 5 or 10% by weight) is used, all under the same conditions as in the actual process, A brass-plated steel wire having a diameter of 1.20 mm was drawn. 1 x 5 x
A 0.25 steel cord was made.

These steel cords were adhered to the rubber compound A or B shown in Table 1 and subjected to an adhesion test and a fatigue test. Regarding the adhesion condition, the optimum vulcanization condition was determined from the vulcanization-torque curve.

For the adhesion test, the pull-out force of the steel cord was measured by the ASTM pull-out test method. Table 2 shows the indexes of the pulling-out force after the primary adhesion and after the wet heat treatment. The wet heat treatment was performed by applying the primary adhesive to 70
It was carried out by keeping it for 2 weeks under wet heat condition of ° C x 96% RH.
As is clear from Table 2, it was found that the wire drawing treated with the lubricant of the present invention had better adhesiveness, and particularly the adhesiveness when wet-heat treated.

Regarding the fatigue test, a steel cord vulcanized with rubber was prepared, and the number of rotations until breakage was measured by a Hunter rotary bending fatigue test. Table 3 shows the indexes of the number of rotations after the primary adhesion and after the wet heat treatment until the fracture. Wet heat treatment, primary adhesion, 70 ℃ × 96%
It was carried out by keeping it under the humid heat condition of RH for 7 days. As is apparent from Table 3, the fatigue resistance was better when the wire drawing treatment was performed using the lubricant of the present invention both after the primary adhesion and after the wet heat treatment.

[0049]

[Table 1]

[0050]

[Table 2]

[0051]

[Table 3]

[0052]

As described above in detail, by using the method of the present invention, the surface of the steel wire can be effectively treated with the triazine thiol derivative, the adhesiveness with the rubber is improved, and the adhesive composite material Properties such as fatigue resistance can be improved.

[Brief description of drawings]

FIG. 1 shows a steel wire drawn by a method of the present invention and a conventional method using a lubricant containing F.
The figure which shows the relationship between a density | concentration and the sulfur peak ratio measured by ESCA analysis.

FIG. 2 shows a steel wire drawn with a lubricant containing DB by the method of the present invention and a conventional method,
The figure which shows the relationship between DB concentration and the sulfur peak ratio measured by ESCA analysis.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Umehara 3-10-10 Imazato, Ikuno-ku, Osaka-shi, Osaka (72) Inventor Nobuyuki Shiratori 967 1972 Shimoinakichi, Chiyoda-mura, Shinji-gun, Ibaraki (72) Invention Person Masataka Katayama 2296 Shimoinekichi, Chiyoda-mura, Shinji-gun, Ibaraki Tokyo Tetsu rope apartment A1 No. 401

Claims (1)

[Claims] 1. A method for surface treatment of a steel wire, which comprises adding a solution of a triazine thiol derivative dissolved in ethanolamine to a lubricant, and wire-drawing and surface-treating the steel wire in the lubricant. ..