JPH07117167A - Composite for metal gasket, method of electrochemical surface treatment of nickel-plated metal plate, and metal plate having surface-treated nickel plating layer - Google Patents

Abstract

(57) [Summary] [Purpose] A composite for a metal gasket in which a vulcanizable fluororubber composition is vulcanized and adhered to a nickel-plated metal plate, which has improved storage stability and is added to a vulcanizable fluororubber composition. To provide a method for producing a nickel-plated metal plate having excellent sulfur adhesion and a surface-treated nickel-plated metal plate. A composite for a metal gasket comprises a vulcanizable fluororubber composition containing a triazinethiol quaternary ammonium salt derivative on a nickel-plated metal plate which is electrochemically surface-treated with a triazinethiol derivative. It is vulcanized and bonded. The electrochemical treatment is performed by passing a current through an anode made of a metal plate having a nickel plating layer of 0.2 μm or more and a cathode other than the metal plate in an electrodeposition solution containing a triazine thiol derivative, so that the metal surface is treated with triazine. It is carried out by treating with a thiol derivative.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite for a metal gasket having an improved vulcanization adhesion between a nickel-plated metal plate surface-treated with a triazinethiol derivative and fluororubber, and a nickel-plated metal plate. And a surface-treated nickel-plated metal plate having improved durability and vulcanization adhesion to fluororubber.

[0002]

2. Description of the Related Art A composite body obtained by bonding metal and rubber is
It is beginning to be used in the fields of open / close sensors, anti-vibration rubber and metal gaskets. Most of these adhesives are produced by subjecting a metal to chemical conversion treatment, applying a primer for adhesion, laminating a rubber composition or applying a solution of a rubber composition, and then vulcanizing. But,
As the size of the adhesive becomes smaller, it becomes more difficult to apply the adhesive primer, and depending on the use environment, deterioration of the adhesive primer may cause performance deterioration such as peeling of the adhesive composite. For example, fluororubber is often used in a harsh environment because of its excellent chemical resistance and heat resistance. However, when it is used as an adhesive composite with a metal, the adhesive primer can withstand the harsh environment. It cannot be done and deteriorates, and the fluororubber peels from the metal.

As a method of improving such problems,
A method has been proposed in which a metal material is electrochemically surface-treated in advance to form a composite with a polymer material such as rubber (Japanese Patent Application Laid-Open No. HEI-2).
-298284). According to this method, the surface of the metal material is electrochemically polymerized with a triazinethiol derivative to enhance the durability of the metal material and to improve the vulcanization adhesion to rubber or the like. However, even if it is difficult to adhere metals such as stainless steel, the surface treatment with the derivative does not improve the adhesion.

Further, a method of subjecting a steel wire to a wire drawing surface treatment by using a lubricant containing the derivative (Japanese Patent Laid-Open No. Hei.
No. 212524), and a method of subjecting a brass-plated steel wire to a wire drawing surface treatment or electrolytic polymerization treatment in the same manner (JP-A-2-209930). However, in these methods, the adherend is a wire,
There is a restriction that brass plating needs to be performed with a sufficient thickness and that it is effective only for natural rubber.As a continuous treatment method for wide coiled products, It has the drawback of not being applicable.

In order to solve the above problems, for example, in the case of adhering a metal and a fluororubber, a simple high-speed treatment that gives a sufficient adhesive strength on the metal side and a sufficient property on the fluororubber side are sufficient. It is necessary to highly balance the composition of the fluororubber with the surface treatment of the metal so as to provide a strong bond with the treatment layer.

[0006]

The present invention solves the above problems and provides a strong adhesive composite of a metal plate and a fluororubber. Therefore, the surface treatment of the metal plate, the compounding of the fluororubber and the method for producing the same are described. It is provided.

[0007]

According to the present invention,
Electrochemically formula 1

[Chemical 3] (R in the formula is -OR ', -SR', -NHR ', -N
(R ') 2, R'is an alkyl group, an alkenyl group,
An aralkyl group, an aralkylphenyl group, an aryl group or a cycloalkyl group is shown. M is H, Na, Li,
K, 1 / 2Ca, 1 / 2Ba, aliphatic primary, secondary and tertiary amine salts, and quaternary ammonium salts. ) To a nickel-plated metal plate surface-treated with a triazinethiol derivative,

[Chemical 4] (R1 in the formula is -SH, -OR ", -SR", -NH
R ″ and —N (R ″) 2, wherein R ″ represents an alkyl group, an alkenyl group, an aryl group, an aralkyl group or a cycloalkyl group, and X ⁻ represents a quaternary ammonium salt. Provided is a composite for a metal gasket obtained by vulcanizing and adhering a vulcanizable fluororubber composition containing a quaternary ammonium salt derivative of thiol.

Further, according to the present invention, 0.2 in the electrodeposition liquid containing the triazine thiol derivative represented by the above chemical formula 1
An electrochemical surface of a nickel-plated metal plate, characterized in that an electric current is passed through an anode made of a metal plate having a nickel plating layer of μm or more and a cathode other than the metal plate to treat the metal plate with a triazinethiol derivative. Provided is a metal plate having a nickel plating layer of 0.2 μm or more, which is surface-treated with a triazine thiol derivative represented by the chemical formula 1 by a treatment method and electrochemically.

The electrochemical surface treatment of the present invention is represented by the chemical formula 1
By using an aqueous solution of a triazine thiol derivative or a solution of a solvent that dissolves the derivative as an electrodeposition liquid, and applying current to the anode of a nickel-plated metal plate having a plating thickness of 0.2 μm or more and the cathode other than the metal plate. The surface of a metal plate is treated with the derivative.

The metal to be nickel-plated in the present invention is not particularly limited, but industrially a stainless steel plate is particularly useful. Stainless steel plates are nickel plated by nickel strike plating. Nickel strike plating is usually performed by immersing a metal in a strike plating bath consisting of an aqueous solution of nickel chloride and hydrochloric acid, with a current density of 5 A / dm.
This is a method of performing nickel plating so that the plating thickness becomes 0.2 μm or more under the condition of about ² . If the plating thickness does not reach the above-mentioned value by this method, the thickness can be 0.2 μm or more by applying electric nickel plating or electroless nickel plating on it. When the metal plate is a steel plate such as a cold rolled steel plate, it is usually plated by electric nickel plating or electroless nickel plating. Whichever method is used for plating, if the nickel plating thickness is less than 0.2 μm, the surface treatment with the triazinethiol derivative will be insufficient, and a composite with a fluororubber composition having satisfactory adhesive strength will be obtained. I can't. The preferable nickel plating thickness is 0.25 μm
As described above, when the thickness is 2 μm or more, the adhesive strength is saturated, which is economically wasteful.

The triazine derivative represented by the chemical formula 1 used for treating the above-mentioned nickel-plated metal plate is as follows:
1,3,5-triazine-2,4,6-trithiol,
1,3,5-triazine-2,4,6-trithiol
Monosodium, 1,3,5-triazine-2,4,6
-Trithiol / triethanolamine, 6-anilino-1,3,5-triazine-2,4-dithiol, 6-
Anilino-1,3,5-triazine-2,4-dithiol monosodium, 6-dibutylamino-1,3,5
-Triazine-2,4-dithiol, 6-dibutylamino-1,3,5-triazine-2,4-dithiol monosodium, 6-diallylamino-1,3,5-triazine-2,4-dithiol, 6-diallylamino-
1,3,5-Triazine-2,4-dithiol monosodium, 1,3,5-triazine-2,4,6-trithiol di (tetrabutylammonium salt), 6-dibutylamino-1,3,3 5-triazine-2,4-dithiol tetrabutylammonium salt, 6-dioctylamino-1,3,5-triazine-2,4-dithiol, 6-dioctylamino-1,3,5-triazine-
2,4-Dithiol monosodium, 6-dilaurylamino-1,3,5-triazine-2,4-dithiol, 6-dilaurylamino-1,3,5-triazine-
2,4-Dithiol monosodium, 6-stearylamino-1,3,5-triazine-2,4-dithiol, 6-stearylamino-1,3,5-triazine-
2,4-dithiol monopotassium, 6-oleylamino-1,3,5-triazine-2,4-dithiol, 6
-Oleylamino-1,3,5-triazine-2,4-
Examples include dithiol monopotassium.

These triazinethiol derivatives are dissolved in water or a soluble solvent and used as an electrodeposition solution. The derivative is used alone or in combination of two or more. The concentration in the electrodeposition liquid is usually 0.05 to 2% by weight. As the solvent for dissolving the derivative, methyl alcohol, ethyl alcohol, isopropyl alcohol, acetone, toluene,
Examples thereof include organic solvents such as ethyl cellosolve, dimethylformaldehyde, tetrahydrofuran, methyl ethyl ketone, benzene and ethyl acetate.

The electrochemical treatment of a nickel-plated metal plate is carried out by using the metal plate as an anode and a platinum plate, titanium plate, stainless steel plate or carbon plate other than the metal as a cathode in the above electrodeposition liquid, At a voltage of 20 V or less, 0.1 mA /
Current of dm ^{2 to} 10 A / dm ² at 0 to 80 ° C. for 0.1 seconds
It is performed by energizing for about 10 minutes. By this treatment, a nickel-plated metal plate whose surface is coated with the triazinethiol derivative is obtained.

The electrochemically treated nickel-plated metal sheet is laminated with a vulcanizable fluororubber composition containing a quaternary ammonium salt derivative of triazinethiol represented by the chemical formula 2 and vulcanized. A composite for metal gasket in which the metal plate and the vulcanized fluororubber composition are adhered can be obtained.

As the fluororubber in the present invention, usual ones can be used and are not particularly limited. For example, tetrafluoroethylene, hexafluoropropylene, trifluorochloroethylene, vinyl fluoride, vinylidene fluoride. And homopolymers or copolymers of fluorine-containing unsaturated monomers such as perfluorovinyl ether, copolymers of other monomers copolymerizable with these monomers, and the like.

The quaternary ammonium salt derivative of triazine thiol represented by the above chemical formula 2 added to the fluororubber in the present invention is obtained by reacting a triazine thiol compound and a quaternary ammonium salt in the presence of an alkali. To be The quaternary ammonium salt is not limited in the present invention, and any quaternary ammonium salt may be used.

Triazine thiol compounds include di- or trithiol-s-triazines. Specific examples include 1,3,5-triazine-2,4,6-trithiol, 6-anilino-1,3,5-triazine-2,4-
Dithiol, 6-dibutylamino-1,3,5-triazine-2,4, -dithiol, 6-diallylamino-
1,3,5-triazine-2,4-dithiol, 6-octylamino-1,3,5-triazine-2,4, -dithiol and the like can be mentioned.

The quaternary ammonium salt is not limited at all,
Those having various substituents are used. Specific examples thereof include tetraethylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium iodide, cetyldimethylethylammonium bromide, cetylpyridinium chloride, cetylpyridinium sulfate, trimethylbenzylammonium borate, 1,8-diaza-bicyclo (5 , 4,0) Undecene-7-methylammonium methosulfate and the like.

The amount of the quaternary ammonium salt derivative of triazine thiol used is usually 0.01 to 5 parts by weight, preferably 0.5 to 2 parts by weight, per 100 parts by weight of the fluororubber. The derivative acts not only as a vulcanizing agent for the fluororubber but also as an accelerator for vulcanizing adhesion with the nickel-plated metal plate surface-treated with the triazinethiol derivative.

The vulcanizable fluororubber composition in the present invention may optionally contain a vulcanizing agent, a processing aid, a reinforcing agent, a filler, a softening agent, a plasticizer, an antiaging agent and the like which are usually used. be able to. The rubber composition of the present invention can be obtained by kneading a fluororubber with the above quaternary ammonium salt derivative of triazine thiol and the above-mentioned optional components with a roll, Banbury, or the like.

Examples of the vulcanizing agent for fluororubber which can be used in combination with the quaternary ammonium salt derivative of triazine thiol include commonly used vulcanizing agents such as polyol, organic peroxide and amine.

In the metal gasket composite of the present invention, the nickel-plated metal plate surface-treated with the previously prepared triazinethiol derivative and the vulcanizable fluororubber composition molded into a predetermined shape are adhered to each other. By vulcanizing under desired heating conditions (usually at 100 to 250 ° C. for 1 minute to 1 hour), a firmly bonded rubber-metal composite can be obtained. Alternatively, the vulcanizable fluororubber composition may be dissolved in an organic solvent such as methyl ethyl ketone or tetrahydrofuran, applied to the metal plate to a predetermined thickness, dried, and then vulcanized.

[0023]

EXAMPLES The present invention will be described more specifically with reference to the following Reference Examples and Examples. The parts and% in the examples and comparative examples are based on weight unless otherwise specified.

Reference Example 1 (Preparation Example of Nickel Plated Metal Plate) A stainless steel plate (SUS304) was immersed in a strike plating bath composed of an aqueous solution of nickel chloride and hydrochloric acid, and a predetermined plating thickness was obtained under the condition of a current density of 5 A / dm ^2. Nickel plating was performed (nickel plating S). As the electroless nickel plating method, an electroless nickel plating solution (Summer Blue) manufactured by Kanigen Japan Co., Ltd. is used,
A cold-rolled steel plate (SPCC) was nickel-plated to have a predetermined plating thickness (nickel plating C).

Reference Example 2 (Preparation example of vulcanizable fluororubber compound) According to the compounding recipe shown in Table 1, a fluororubber and a compounding agent were mixed on a roll to prepare a rubber compound. The formulation was formed into a 2 mm thick sheet. In addition, 17
A test piece primary vulcanized by pressing at 0 ° C. for 20 minutes and a test piece secondary vulcanized at 200 ° C. for 24 hours after the primary vulcanization were prepared, and vulcanized physical properties were measured according to JISK6301 and the results are shown in a table. It was also written in 1.

[0026]

[Table 1]

Examples 1 to 3 and Comparative Examples 1 to 5 1,3,5-triazine-2,4, using a stainless steel plate plated with nickel S as an anode and a carbon plate as a cathode.
0.05 mol / l of 6-trithiol monosodium salt
LiClO ₄ as a supporting electrolyte in an aqueous solution of 5 × 10 ⁻⁴
Current density of 0.1 mA /
A current is applied for 5 seconds to 10 minutes in the range of dm ^{2 to} 10 A / dm ² , and the rubber sheet prepared in Reference Example 2 is adhered to the mold immediately after the treatment and after 1 week of storage, and then put into a mold to obtain 80 kg / cm.
Press vulcanization (primary vulcanization) was performed at 170 ° C. for 20 minutes under the pressure of ² , and then secondary treatment was performed at 200 ° C. for 24 hours to produce a metal-fluororubber composite. The adhesive strength between the rubber and the metal plate was measured according to the peeling test of JIS K6301. The results are shown in Tables 2 and 3. The peel strength values in the table indicate the peel strength after storage for 1 week, and the values in parentheses indicate the peel strength immediately after the stainless steel plate was treated. The same applies to the following examples.

Example 4 Methanol solution of 1,3,5-triazine-6-diallylamino-2,4-dithiol monosodium salt as a triazinethiol derivative, Li as a supporting electrolyte
A stainless plate was treated under the same conditions as in Example 1 except that BF ₄ was used to prepare a metal-fluorine rubber composite. The adhesive strength was measured, and the results are shown in Table 2.

Example 5 A metal-fluorine rubber composite was prepared by treating a nickel-plated metal plate with a triazinethiol derivative in the same manner as in Example 1 except that the cold-rolled steel plate plated with nickel plating C of Reference Example 1 was used. It was created. The adhesive strength is shown in Table 2.

[0030]

[Table 2]

[0031]

[Table 3]

From the results of Tables 2 and 3, the metals of the present invention were
The rubber composite has excellent adhesion between the nickel-plated metal plate and the rubber composition, but the nickel plating thickness is 0.2 μm.
Use a metal plate that is less than the following, and the plating thickness is 0.2μ
It can be seen that a sufficient adhesive force cannot be obtained with a nickel-plated metal plate that has not been subjected to electrochemical treatment in a triazine thiol derivative solution, although it is m or more. Further, when the electrochemical treatment is applied, the peel strength does not change immediately after the treatment or after 1 week of storage. It can also be seen that the peel strength is significantly reduced by storage when no electrochemical treatment is applied.

[0033]

The triazinethio-obtained by the method of the present invention
A nickel-plated metal plate surface-treated with a ru derivative is laminated with a vulcanizable fluororubber composition after storage and vulcanized and adhered, and the peel strength is not reduced. The composite of the surface-treated nickel-plated metal plate and fluororubber is excellent in peel strength, and is particularly useful for producing a metal gasket that requires oil resistance, heat resistance, and chemical resistance.

Front page continuation (72) Inventor Akane Fujii 7-1, Takaya Shinmachi, Ichikawa, Chiba Nisshin Steel Co., Ltd. (72) Inventor Hidetoshi Yamabe 7-1, Takaya Shinmachi, Ichikawa, Chiba Nisshin Steel Co., Ltd. (72) Inventor Yasugi Iwasaki 1-2-1, Yokou, Kawasaki-ku, Kanagawa, Japan ZEON CORPORATION (72) Inventor Kiyoyuki Hosoya 1-2-1, Yokou, Kawasaki-ku, Kawasaki, Kanagawa In-house (72) Inventor Hidetoshi Hirahara 1-14-55 Takamatsu, Morioka-shi, Iwate Prefecture (72) Yaeko Sasaki Inventor 69-24 Sakaimori, Ukai character, Takizawa-mura, Iwate-gun, Iwate Prefecture

Claims (3)

[Claims] 1. A chemical formula 1 electrochemically (R in the formula is -OR ', -SR', -NHR ', -N
(R ') 2, R'is an alkyl group, an alkenyl group,
An aralkyl group, an alkylphenyl group, an aryl group or a cycloalkyl group is shown. M is H, Na, Li,
K, 1 / 2Ca, 1 / 2Ba, aliphatic primary, secondary and tertiary amine salts, and quaternary ammonium salts. ) Is added to the nickel-plated metal plate surface-treated with the triazinethiol derivative shown in Chemical Formula 2 (R1 in the formula is -SH, -OR ", -SR", -NH
R ″ and —N (R ″) 2, R ″ represents an alkyl group, an alkenyl group, an aryl group, an aralkyl group or a cycloalkyl group, and X ⁺ represents a quaternary ammonium salt. A composite for a metal gasket obtained by vulcanizing and adhering a vulcanizable fluororubber composition containing a quaternary ammonium salt derivative of thiol. 2. An electric current is passed through an anode made of a metal plate having a nickel plating layer of 0.2 μm or more and a cathode other than the metal plate in an electrodeposition liquid containing the triazine thiol derivative represented by the chemical formula 1 to supply the metal plate. Is treated with a triazine thiol derivative, and an electrochemical surface treatment method for a nickel-plated metal plate. 3. A metal plate having a nickel plating layer of 0.2 μm or more which is electrochemically surface-treated with the triazine thiol derivative represented by the chemical formula 1.