JPH0650367A - Disk pad - Google Patents

Abstract

PURPOSE:To provide an automobile disk pad which is constituted so that little water may permeate into the voids of a frictional member. CONSTITUTION:As for a disc pad which is constituted of a frictional member containing the fiber component other than asbestos, thermosetting resin component such as phenol resin, and a filling material component such as graphite and a back metal, each silicone resin covering film is formed on the side surface of the frictional member and a back metal boss opening part.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a disk pad for an automobile, which is excellent in waterproofness due to an improved coating process.

[0002]

2. Description of the Related Art A friction material used as an automobile disk pad uses heat-resistant organic fibers, glass fibers, metal fibers or the like as a fiber component, and a thermosetting resin such as phenol resin as a binder and a filler component. As such, graphite, molybdenum disulfide, etc. are used. The disk pad is manufactured by mixing the friction material, then performing molding and heat treatment, and then spraying or electrodeposition coating a water-soluble paint on the side surface of the friction material and the surface of the back metal for the purpose of adjusting the appearance. There is.

[0003]

Disc pads have a porosity of 5 to 20 in order to maintain good friction and wear performance.
It is manufactured by adjusting the volume to about%. In particular, recently, a material using a porous material has been developed to prevent squeal during braking. However, if water enters the voids from the outside, the heat generated by braking may cause the water to evaporate abruptly, causing cracks on the side surfaces of the friction material. Such problems can be prevented to some extent by coating the friction material after the heat treatment,
The effect of spraying a water-soluble paint is small, and the effect of waterproofing by electrodeposition coating is slightly better than that of a spray coating of a water-soluble paint. Therefore, the problem to be solved by the present invention is to provide a disk pad in which water does not enter the gaps of the friction material.

[0004]

The present invention has been made for the purpose of solving the above problems, and comprises a fiber component other than asbestos, a thermosetting resin component such as phenol resin, and a filler component such as graphite. In a disc pad composed of a friction material containing a metal and a back metal, a silicon resin coating is formed on a side surface of the friction material and a boss hole portion of the back metal. That is, the inventor of the present invention knows that the coating is formed on the friction surface by sliding with the mating material, so that the above problems can be solved by preventing the infiltration of water from the friction material side surface and the boss hole. Thus, the present invention has been achieved.

The silicon resin film of the present invention can be formed by applying a silicic acid resin coating material. The silicic acid resin paint is prepared by dissolving an initial condensate prepared by mixing monomethyl or monoethyltrichlorosilane with a small amount of dimethyl and diethyldichlorosilane in an appropriate solvent.

There are two possible timings for applying the silicic acid resin coating, during molding and heat treatment, and after heat treatment. Since the surface of the friction material has less unevenness and the coating is better before heat treatment than before heat treatment, It is preferable to paint between molding and heat treatment in terms of waterproof effect. Further, since the silicic acid resin coating material has high heat resistance and is hardly deteriorated by the heat treatment, there is no need to re-coat the heat treatment. The coating before the heat treatment prevents oxidative deterioration of the friction material during the heat treatment and has a good effect on the strength.

[0007]

In the disk pad of the present invention, a silicon resin coating is formed on the side surface of the friction material and the boss holes where water easily penetrates by applying the silicic acid resin paint, so that water penetrates into the pores of the friction material. As a result, cracking due to rapid evaporation of water can be prevented.

[0008]

EXAMPLES Next, examples of the present invention will be described. Using non-asbestos-based friction materials that have been conventionally used, mix them uniformly with a stirrer, and then preform, heat and pressure mold them to obtain disk pad intermediate products for Examples and Comparative Examples. Obtained.

Example 1 The side surface of the friction material and the back metal of the above intermediate product were coated with a silicic acid resin paint, and then heat treated to obtain a disk pad of Example 1. Example 2 After heat-treating the above intermediate product, a silicic acid resin coating material was applied to the side surface of the friction material and the back metal to obtain a disk pad in Example 2.

Comparative Example 1 After heat-treating the above intermediate product, a melamine alkyd water-soluble paint was spray-painted on the side surface of the friction material and the back metal to obtain a disk pad of Comparative Example 1. Comparative Example 2 After heat-treating the above intermediate product, an epoxy water-soluble paint was electrodeposited on the friction material side surface and the back metal to obtain a disk pad of Comparative Example 2.

Table 1 shows the results of a water absorption test and a crack test performed on the disk pads of Examples and Comparative Examples obtained by the above method. In the water absorption test, the disc pad is completely immersed in water, and the ratio of the weight of water absorbed to the total weight of the friction material after a certain period of time is measured. In the crack test, a braking start temperature of 300 ° C. and an initial speed of 120 km / h were repeatedly braked 100 times, and then the disc pad was immersed in water for 1 hour, and this operation was repeated for several cycles. It measures the state of.

[0012]

As described above, the disk pad of the present invention is
A disk pad composed of a friction material containing a fiber component other than asbestos, a thermosetting resin component such as phenol resin, and a filler component such as graphite, and a back metal, and silicon on the friction material side surface and the boss hole of the back metal. As a result of forming a resin film, the penetration of water into the friction material is reduced, and cracks due to rapid evaporation of water inside the friction material during braking can be prevented, making it suitable as a disc pad used in automobiles. Is.

[Table 1]

Claims (2)

[Claims] 1. A disk pad comprising a friction material containing a fiber component other than asbestos, a thermosetting resin component such as phenol resin, and a filler component such as graphite, and a back metal. A disk pad, wherein a silicon resin film is formed on one or both of the parts. 2. The disk pad according to claim 1, wherein the silicon resin film is formed by a coating process.