JP2831491B2 - Friction material containing thermosetting resin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a friction material containing a thermosetting resin.

[0002]

2. Description of the Related Art Friction materials used for automobiles, motorcycles and the like include:
There are brake linings, disc pads, clutch fading, etc. These friction materials are generally metal powder,
It is formed by binding a friction modifier containing a lubricant, an inorganic filler, an organic filler, and the like, and a reinforcing material made of fibers such as aramid fibers with a binder of a thermosetting resin. Since the friction material of an automobile or the like is heated to a high temperature during braking, it is required to have a so-called fade resistance with little change in the friction coefficient (μ) even at a high temperature. Conventionally, in order to improve the fade resistance, as described in JP-A-63-293337, an inorganic coating agent is impregnated in a molded article obtained by thermoforming a friction adjusting material and a reinforcing material with a thermosetting resin. Friction materials are known.

[0003]

According to the above-mentioned conventional friction material, there is an advantage that fade resistance under high temperature load and high temperature wear resistance are improved. However, since this friction material is thermoformed with a thermosetting resin and then impregnated with an inorganic coating agent, there is a problem that the number of manufacturing steps is large and the cost is high.

Accordingly, the present invention has been made to solve the above problems, and it is an object of the present invention to provide a thermosetting resin-containing friction material which is inexpensive and has excellent properties such as fade resistance and high temperature wear resistance. In providing materials.

[0005]

The present invention has the following arrangement to achieve the above object. That is, in a thermosetting resin-containing friction material in which a friction modifier containing a filler and a reinforcing material are fixed with a thermosetting resin binder, the binder has a thermosetting resin A having a short flow distance and a short gel time. It is characterized in that two types of thermosetting resins, thermosetting resin B, having a longer flow distance and longer gel time than thermosetting resin A are used. The flow distance of the thermosetting resin A is 10 to 20
mm, the gel time is 10 to 20 seconds, the flow distance of the thermosetting resin B is 30 to 40 mm, and the gel time is 60 to
Preferably, it is 80 seconds. Melting point of thermosetting resin A is 4
0 to 70 ° C., and the melting point of the thermosetting resin B is 71 to 10
It is preferred that the temperature is 0 ° C. The ratio between the thermosetting resin A and the thermosetting resin B is preferably in the range of 1: 3 to 3: 1 in terms of volume ratio.

[0006]

In order to improve the fade resistance under a high temperature load, one condition is that the gas is ejected from the friction material at a high temperature, so that the gas can be discharged well.
Generally, the higher the porosity of the friction material, the better the gas exhaustability. In the present invention, the thermosetting resin for binding the friction modifier and the reinforcing material to the thermosetting resin A has a shorter flow distance and a shorter gel time, and the thermosetting resin B has a longer flow distance and a longer gel time than the thermosetting resin A. Since two types of thermosetting resins are used, the thermosetting resin A thermosets faster at the time of thermosetting during molding, and the flowability of the resin is low. Pores are generated between the thermosetting resin A and the thermosetting resin B, and the porosity can be increased. As a result, especially the fade resistance was improved.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In the present invention, two types of thermosetting resins, a thermosetting resin A having a short flow distance and a short gel time and a thermosetting resin B having a long flow distance and a long gel time than the thermosetting resin A, are used as the binder. There are features. In this case, the thermosetting resin A has a flow distance of 10
~ 20mm, gel time is 10 ~ 20 seconds, thermosetting resin B has a flow distance of 30 ~ 40mm, gel time is
Those for 60 to 80 seconds are preferred. The flow distance and gel time are based on JIS K6910. Further, the thermosetting resin A preferably has a melting point of 40 to 70 ° C, and the thermosetting resin B preferably has a melting point of 70 to 100 ° C.

Various kinds of thermosetting resins satisfying the above conditions can be selected depending on the degree of polymerization and the like. For example, thermosetting resin A includes a phenolic straight resin,
Phenolic melamine modified resin, phenolic rubber modified resin and the like. Further, the thermosetting resin B includes a phenolic rubber modified resin, a phenolic straight resin, and a phenolic melamine modified resin. The ratio between the thermosetting resin A and the thermosetting resin B is not particularly limited as long as there is no problem with the mixing property. However, in order to obtain the porosity required for excellent fade resistance described later, the ratio between the two is approximately 1: A range of 3 to 3: 1 is preferred. In addition, the amount of the thermosetting resin A and the thermosetting resin B corresponding to the entire friction material is generally 5 to 30 vol%. If it is less than 5%, the moldability is poor, and if it is more than 30%, there is a problem in the heat resistance of the friction material.

The friction-adjusting material and the reinforcing material only need to have good binding properties with the thermosetting resin and obtain the required friction characteristics.
The material and mixing amount are not particularly limited. As the friction adjusting material, metal powders such as iron and copper, lubricants such as graphite, inorganic fillers such as barium sulfate, and organic fillers such as organic dust are used. Aramid fibers and other fiber materials are used for the reinforcing material.

In order to improve the fade resistance under a high temperature load, one condition is to make it possible to discharge the gas satisfactorily because the gas is ejected from the friction material at a high temperature. Generally, the higher the porosity of the friction material, the better the gas exhaustability. In the present invention, the thermosetting resin for binding the friction modifier and the reinforcing material to the thermosetting resin A has a shorter flow distance and a shorter gel time, and the thermosetting resin B has a longer flow distance and a longer gel time than the thermosetting resin A. Since two types of thermosetting resins are used, the thermosetting resin A thermosets faster at the time of thermosetting during molding, and the flowability of the resin is low. Pores are generated between the thermosetting resin A and the thermosetting resin B, and the porosity can be increased. As a result, the fade resistance was improved. The higher the amount of the thermosetting resin A used, the higher the porosity, but the lower the adhesion to the friction modifier and the reinforcing material. The thermosetting resin B, which has a longer flow distance and longer gel time, has better adhesion to the friction modifier and the reinforcing material. The range in which the porosity can be improved and the adhesiveness with the friction modifier and the reinforcing material is good is that the ratio of the thermosetting resin A and the thermosetting resin B is approximately 1: 3 to The range is 3: 1.

Further, when the melting point of the thermosetting resin A is lower than the melting point of the thermosetting resin B, the thermosetting resin A melts faster during molding and gelation is further accelerated, so that the porosity increases. It is effective. In addition, as a result of the improvement in the fade resistance, the high-temperature wear resistance was improved, and the high-speed friction coefficient did not change significantly. Further, by using two types of thermosetting resins, the adhesive strength to the substrate was increased.

Table 1 shows the compositions of the examples and comparative examples. Table 2
Table 3 shows comparative data of abrasion resistance, and Table 3 shows comparative data of adhesive strength.

[0013]

[Table 1]

[0014]

[Table 2]

[0015]

[Table 3]

FIG. 1 shows a change in friction coefficient (fade resistance) with temperature, and FIG. 2 shows a change in friction coefficient at high speed. As is clear from Tables 2 and 3, the present example is superior in both abrasion resistance and adhesive strength to a substrate as compared with the comparative example of the conventional product, and as is clear from FIG. Has almost no change in the coefficient of friction under a high temperature load and is excellent in fade resistance. Further, as is apparent from FIG. 2 , in the present embodiment, the change in the friction coefficient at high speed is small, and a stable braking effect can be obtained. In the above example, the ratio of the thermosetting resin A to the thermosetting resin B was set to 1: 3, but the same good result was obtained when the ratio was set to 3: 1. Although the present invention has been described in detail with reference to the preferred embodiments, the present invention is not limited to the embodiments, and it goes without saying that many modifications can be made without departing from the spirit of the invention. .

[0017]

According to the friction material containing a thermosetting resin according to the present invention, the friction material can be provided at a low cost without increasing the number of manufacturing steps.
The porosity is improved, and in particular, it has a remarkable effect of being excellent in fade resistance and high-temperature wear resistance.

[Brief description of the drawings]

FIG. 1 is a graph showing a change in friction coefficient with temperature.

FIG. 2 is a graph showing a change in friction coefficient at a high speed.

Claims (4)

(57) [Claims] 1. A thermosetting resin-containing friction material in which a friction modifier containing a filler and a reinforcing material are fixed with a thermosetting resin binder, wherein the binder has a short flow distance and a short gel time. A thermosetting resin-containing friction material comprising two types of thermosetting resins, a resin A and a thermosetting resin B having a longer flow distance and a longer gel time than the thermosetting resin A. 2. The flow distance of the thermosetting resin A is 10 to 2
0 mm, the gel time is 10 to 20 seconds, the flow distance of the thermosetting resin B is 30 to 40 mm, and the gel time is 60.
2. A friction material containing a thermosetting resin according to claim 1, wherein the friction material has a duration of from 80 to 80 seconds. 3. The thermosetting resin according to claim 1, wherein the melting point of the thermosetting resin A is 40 to 70 ° C., and the melting point of the thermosetting resin B is 71 to 100 ° C. Contains friction material. 4. The thermosetting resin-containing composition according to claim 1, wherein the ratio of the thermosetting resin A to the thermosetting resin B is 1: 3 to 3: 1 in terms of volume ratio. Friction material.