JPH04115943A - Composite of rubber and aluminum or alloy thereof, and manufacture thereof - Google Patents

Abstract

PURPOSE:To enhance the peeling resistance and secondary processability after vulcanizing adhesion of the adhesive layer of rubber and aluminum by forming a simultaneous vulcanization type adhesive surface to at least a part of the chromate chemical forming treatment surface formed to an aluminum base material and bringing a vulcanizable rubber composition into contact with the adhesive surface to carry out vulcanizing adhesion. CONSTITUTION:A vulcanizable rubber composition is brought into contact with the dried simultaneous vulcanization type adhesive surface applied to at least a part of the chromate chemical forming treatment surface having a film wt. of 50-250mg/m<2> formed to an aluminum base material to be subjected to vulcanizing adhesion. As the raw material rubber constituting the rubber composition, natural rubber, synthetic rubber or a mixture of them is used and usual compounding agents such as zinc oxide, carbon black, an age resistor, a vulcanization accelerator or sulfur are compounded with the raw material rubber to prepare the rubber composition. By this method, the chromate type chemical forming film is optimized as the vulcanizing adhesion substrate between rubber and aluminum and the secondary processing after vulcanizing adhesion such as the draw processing of a rubber vibration insulator becomes possible.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a composite of rubber and aluminum or an alloy thereof (hereinafter simply referred to as aluminum), particularly a rubber compound with excellent salt damage peeling resistance and secondary processing resistance. This invention relates to a composite with aluminum and its manufacturing method.

(Prior art) Aluminum bonding substrate treatment for vulcanization bonding between rubber and aluminum includes mechanical treatment such as dry and wet blasting, and chromic acid treatment for phosphate chemical treatment and anodic oxidation treatment. There are chemical treatments such as chlorination treatment, each with its own characteristics.

For example, blasting has excellent normal adhesion and secondary processing resistance, but when applied to parts of automobiles that run on the road, for example, there is a problem with anti-vibration rubber made of rubber and aluminum base materials. In cold regions such as Japan and North America, large amounts of rock salt and potassium chloride are sprayed to prevent road surfaces from freezing, which can lead to peeling of the vulcanized adhesive layer of these parts in automobiles due to metal corrosion, so-called salt damage peeling. Occur.

Additionally, aluminum is usually not painted because of its high anti-corrosion properties, but corrosion of the aluminum itself can become a problem in the above environment, and as a countermeasure to this, it is recommended to use the aforementioned chemical treatment to prepare the base for bonding. many.

A problem in the development of such technology is particularly in the case of anti-vibration rubber, which requires secondary processing (such as drawing) after vulcanization and adhesion.

For example, for rubber bushings that bond rubber between the inner and outer cylinders that make up the suspension links of automobiles, the durability of the product is improved by drawing the outer cylinder after vulcanization and adhesion. When chemical treatment is employed to improve strength, secondary processing such as drawing causes destruction of the adhesive layer and induces adhesive peeling.

As described above, the salt damage resistance and peeling performance of the adhesive, the secondary processing resistance, and the rust prevention ability are contradictory required properties.

(Tipping Point to be Solved by the Invention) In view of the above points, the present invention aims to improve the peel resistance of the adhesive layer between rubber and aluminum, the secondary processing performance after vulcanization adhesion, and further improve the rust prevention ability of aluminum. The purpose of this project is to provide a composite of rubber and aluminum that satisfies all of the above requirements, as well as a method for manufacturing the same.In particular, this product is used in areas where large amounts of rock salt, potassium chloride, etc. are sprayed for the purpose of preventing road surfaces from freezing during snowy conditions. This feature is used in composites applied to swing rubbers, etc.

(Means for solving the problem) In order to achieve the above object, the present invention employs the following configuration.

That is, the first aspect of the invention is that a simultaneous vulcanization adhesive surface is formed on at least a part of the chromate conversion treated surface formed on the aluminum base material, and a vulcanizable rubber composition is applied to the adhesive surface. The second aspect of the invention relates to a composite of rubber and aluminum, characterized in that they are brought into contact and bonded together by vulcanization, and the second aspect of the invention is to perform chromate chemical conversion treatment on an aluminum base material to form a chromate chemical conversion treated surface. A simultaneous vulcanization adhesive surface is formed by coating at least a portion of the treated surface with a simultaneous vulcanization adhesive and then drying it, and then a vulcanizable rubber is applied to the adhesive surface. The present invention relates to a method for producing a composite of rubber and aluminum, characterized in that the compositions are brought into contact with each other and then vulcanized and bonded by heat and pressure treatment.

In the present invention, as described above, the term aluminum includes aluminum and alloys thereof.

Characteristically, the coating weight formed on the aluminum base material is 50 mg/m'' to 250 mg/m.
/ A vulcanizable rubber composition is brought into contact with the coated and dried simultaneous vulcanization adhesive surface on at least a portion of the chromate treated (chromate treated) surface having properties in the range of 2 to 2;
It is characterized by being vulcanized and bonded.

(Function) The key point of the present invention is to optimize the chromate-based chemical conversion film (chromate film) as a base for vulcanization adhesion between rubber and aluminum, and to perform secondary processing after vulcanization adhesion, such as drawing of anti-vibration rubber. It's what made it possible.

The weight of the chromate-based chemical conversion coating formed in the present invention is preferably 50 to 250 mg/m2, particularly preferably 100 to 200 mg/m2 (the coating weight is measured by X-ray fluorescence analysis or atomic absorption spectrometry). .

Furthermore, the raw rubber constituting the rubber composition used in the present invention may be natural rubber, synthetic rubber, or a mixture thereof, and these raw rubbers may contain zinc oxide, carbon black, antiaging agents, and vulcanization accelerators. , sulfur, and other commonly used compounding agents to form a rubber composition.

In addition, commonly used vulcanization adhesives may be used, and examples of two-component adhesives include Chemlock 205 (phenolic resin-based brimer adhesive) and Chemlock 220 (overcoat adhesive mainly composed of chlorinated rubber) manufactured by Lord Co., Ltd. agent)
etc., and as a one-liquid coating type, Lord's product name Chemlock 2
52 (adhesive mainly composed of chlorosulfonated polyethylene).

(Example) A more detailed explanation will be given below based on examples.

Example I Aluminum base material of round adhesive test piece specified in JIS-6301 (A305 specified in JIS-H4000)
2 and JIS-H5302.
), a chromate film with a film weight of 150 mg/m2 (
After forming a chromate film), a heat-sensitive phenolic resin-based brimer adhesive (Chemlock 205, manufactured by Lord Co., Ltd., USA) was applied as a simultaneous vulcanization adhesive to the adhesion surface with the rubber composition.
) is coated and dried, then a chlorinated rubber overcoat adhesive (Chemlock 220, manufactured by Lord, USA) is coated and dried, and this is inserted into a mold to vulcanize the sulfur-vulcanized natural rubber compound. Glued.

Comparative Example 1 The same procedure as used in Example 1 was carried out except that the blasting treatment was performed on the aluminum base material of the rough adhesive test piece (A3052 specified in JIS-H4000 and ADC12 specified in JIS-H5302). A sample was prepared in the same manner as in Example 1.

Comparative Example 2 A sample was prepared in the same manner as in Example 1, except that anodizing treatment (alumite treatment) was performed on the aluminum base material (A 5052) of a round adhesive test piece.

Regarding the samples of Example 1 and Comparative Examples 1 and 2 above,
Table 1 shows the results of an adhesive strength test according to JIS-6301.

In the table, the number for the destroyed portion indicates the percentage of the destroyed portion.

Moreover, the rusting rate is the rusting area rate on the surface of the non-bonded portion of the rubber.

Furthermore, CCT (test method: Cycle Corrosi
on Te5t) sprayed salt water onto the sample for 19 hours and then added it to Table 1: R: Rubber, RC: Rubber/Ce+e
ant, CP: Q-cho tlPriwr, M
P: Metal/Pr ■■■ One cycle consisted of drying with hot air for 3 hours, then moistening for 2 hours, and then leaving this in a room for 2 hours.

Example 2 A rubber bush constituting an automobile suspension link was subjected to the same treatment as in Example 1 and a sulfur-cured natural comb compound was vulcanized and bonded, and then the outer cylinder was drawn (
A reduction ratio of 5% and 10%) was carried out.

The outline of the rubber bush is as follows. That is, the thickness is 1.
A steel inner tube with a thickness of 2.5 mm and an outer diameter of 19 mm is passed concentrically into an aluminum outer tube with a diameter of 5 mm, an outer diameter of 37 mm, and a length of 45 mm, and rubber is vulcanized and bonded between the two. be.

Comparative Example 3 A rubber bush similar to that used in Example 2 was subjected to the same treatment as in Comparative Example 1, and was further subjected to the same vulcanization adhesion treatment as in Example 2, and the outer cylinder was similarly drawn.

Comparative Example 4 A rubber bush similar to that used in Example 2 was subjected to the same treatment as in Comparative Example 2, and was further subjected to the same vulcanization adhesion treatment as in Example 2, and the outer cylinder was similarly drawn.

Regarding each sample of Example 2 and Comparative Examples 3 and 4 above,
Table 2 shows the results of testing the adhesion state of the vulcanized adhesive layer to the comb in the outer cylinder.

The test is a 90 degree peel test on the adhesive surface of the rubber bush outer cylinder. (The test is based on JIS-6301.) (Effects) As is clear from Tables 1 and 2, the present invention is applicable to all aluminum base materials, and has sufficient initial adhesive strength and Not only does it have sufficient peeling resistance7 and anti-corrosion properties, but it also has sufficient peeling resistance7 and anti-corrosion properties, as well as the ability to withstand vibration-proof rubber, for example, in the drawing process of composites of rubber and aluminum after vulcanization. It maintains a level of adhesion sufficient for practical use even during subsequent processing.

Furthermore, as seen in the above-mentioned examples (the vibration-proof rubber to which the present invention is applied does not show any decrease in its adhesion level even during secondary processing during manufacturing, and has high rust prevention and resistance when used). It can be used in cold regions due to its ability to remove salt damage.

On the other hand, it is an excellent invention that has resolved all the practical points, such as exhibiting high resistance to salt damage and peeling even when the aluminum part of the anti-vibration rubber is used in contact with other metals (e.g. iron). be.

Claims (2)

[Claims] (1) A simultaneous vulcanization adhesive surface is formed on at least a portion of the chromate conversion treated surface formed on the aluminum or aluminum alloy base material, and a vulcanizable rubber composition is applied to the adhesive surface. A composite of rubber and aluminum or its alloy, characterized in that they are brought into contact and vulcanized and bonded. (2) Perform chromate chemical conversion treatment on aluminum or its alloy base material to form a chromate chemical conversion treated surface, apply a vulcanization-type adhesive to at least a portion of the treated surface, and then dry this. A rubber characterized in that a simultaneous vulcanization adhesive surface is formed by this process, a vulcanizable rubber composition is then brought into contact with the adhesive surface, and the rubber composition is then vulcanized and bonded by heat and pressure treatment. A method for manufacturing composites with aluminum or its alloys.