JPS6217435A - Base material for friction material - Google Patents

Abstract

PURPOSE:To contrive to reduce environmental pollution by impregnating a paper-like fabric containing cellulosic fiber, polyamide fiber, glass fiber and frictional property improver with phenol resin. CONSTITUTION:A paper-like fabric containing 5-30wt% of cellulosic fiber such as wood fiber, cotton fiber or the like, 2-30wt% of polyamide fiber such as 'Kevlar' or the like, 2-20wt% of glass fiber, and 30-80wt% of frictional property improver is manufactured by wet paper formation process. Said paper- like fabric is impregnated with phenol resin to form a friction material. The frictional property improver contains fibrous material which can be added at the time of manufacturing, in paper form,titanic acid potash fiber, rock wool, ceramic fiber, carbon fiber and the like in addition to organic or inorganic compounds.

Description

DETAILED DESCRIPTION OF THE INVENTION A9 Object of the Invention (11 Industrial Field of Application) The present invention relates to a base material for a friction material mainly used in a friction clutch.

(2) Conventional technology Conventionally, this type of base material has been made by impregnating asbestos yarn with phenolic resin and adding a friction performance improver to it, or by mixing asbestos, phenolic resin, inorganic powder, etc. It has been known.

(3) Problems to be solved by the invention However, since the base material is made of asbestos,
When the friction material made of the base material wears out, there is a risk that the abrasion powder may pollute the atmosphere, which is not preferable in terms of preventing pollution.

In view of the above, an object of the present invention is to provide the above-mentioned base material from which a friction material having excellent friction performance can be obtained without using asbestos.

B1 Structure of the invention (1) Means for solving the problems The base material for a friction material according to the present invention comprises cellulose fibers 5 to 3
0 weight weight, polyamide fiber aZ~30% by weight, glass fiber 2~20 weight i%, and friction performance agent 30~80 weight%
, a wet-paper-formed paper product containing , and a phenolic resin impregnated into the paper product.

(As mentioned in Section 21, when specific amounts of cellulose fibers, polyamide fibers, glass fibers, and friction performance improvers are blended, the wet formability of the paper product improves, resulting in a friction material base with high production efficiency. In addition, the base material has excellent wear resistance, a large friction coefficient at high and low temperatures and low sliding speeds, has little fade in the initial stage of use, and has excellent friction coefficient characteristics at low temperatures ( To obtain a friction material that has excellent friction performance such as little change in friction coefficient due to slippage, etc., has high rotational fracture strength against centrifugal force, and does not cause pollution. I can do it.

The reason why the content value of the various fibers, etc. was determined to be 5% as described above is as follows.

a. Regarding cellulose fibers, if the content of this fiber exceeds 30% by weight, the amount of wear of the 111 friction material obtained from the base material will increase, and the friction coefficient characteristics at low temperatures will deteriorate, causing problems in vehicles when the clutch is engaged. This causes problems such as vibration, so-called judder, a decrease in the coefficient of friction at high temperatures and low sliding speeds, and an increase in fade in the early stages of use.

Furthermore, if the content of the fibers is less than 5% by weight, problems such as a low coefficient of friction during the initial use of the friction material and at low sliding speeds, and a low rotational breaking strength may occur, and the wet paper forming properties of the paper product may be reduced. becomes worse.

b. Polyamide g! When the fiber content exceeds 3ON%, the friction coefficient of the friction material at the initial stage of use and at low sliding speeds becomes low.

If the content of the fibers is less than 2% by weight, the amount of wear of the friction material increases, the friction coefficient characteristics at low temperatures deteriorate and judder occurs, the friction coefficient at high temperatures decreases, and fading occurs during the initial use. Problems such as an increase in the rotational strength and a decrease in rotational breaking strength occur, and the wet papermaking properties of the papermaking body deteriorate.

C. Regarding glass fiber: If the content of this fiber exceeds the 20M analysis temperature, the friction coefficient of the friction material at low temperatures decreases, and furthermore, the friction coefficient characteristics deteriorate and judder occurs.

Furthermore, if the content of the fibers is less than 2% by weight, the friction material σ) may have problems such as an increase in the amount of wear and a decrease in the coefficient of friction at low sliding speeds. arise.

Regarding the d0M friction performance improver, if the content of this friction performance improver exceeds 80% by weight,
The rotational breaking strength, tensile strength, etc. of the friction material decrease.

Further, if the content is less than 30% by weight, problems such as increased wear of the friction material and deterioration of the friction coefficient characteristics will occur.

(Example 31 Cellulose fibers include wood fibers, cotton fibers such as cotton linter pulp, bast fibers, and rayon.

Examples of polyamide fibers include Kevlar (trade name, manufactured by DuPont, USA), which is an aromatic polyamide fiber, and includes chipped fibers, pulp-like fibers, and the like.

Glass fibers have a diameter of 9 to 13 μm.
It is used by cutting it into lengths of 1, but the most preferable diameter for friction materials is 6 μm.

Friction performance improvers include, in addition to general organic and inorganic materials, potassium titanate fibers, rock wool, ceramic fibers,
It includes fibrous materials that can be added during papermaking, such as carbon fibers. Metal powders and metal #& fibers are also sometimes used as friction performance improvers.

The table below shows formulation examples of the base material of the present invention and Comparative Examples I to (2).

The numerical unit is weight %.

In the above table, the average fiber length of Kevlar pulp is 51, and the glass fiber has a diameter of 6 μm and a length of 6M. The friction performance improver is also a mixture of cashew dust, potassium titanate fibers, barium sulfate, calcium carbonate, and metal fibers containing metal powder.

A wet papermaking method was applied using the formulations in the table above, and the thickness was 0.
8 to 1, Q 1111 were obtained, each paper product was impregnated with phenolic resin in an amount of is: *i of the total weight of the base material, dried, and each dried product was wound up. Cut into strips with a width of 8 strips to obtain four types of base materials.

Using each base material, heat and pressure molding is performed using a conventional method, and the outer diameter is 200.
1. A friction material χ for a friction clutch with an inner diameter of 14 QllEIm, a thickness of 3.5 wg, and a specific gravity of 1.3 to 1.4 was obtained.

Each friction material is attached to an inertial body type clutch full-size tester, the inertial body (flywheel) is rotated at a predetermined number of rotations, the drive of the inertial body is stopped, and then the clutch is engaged and engaged to reduce the friction of each friction material. When the coefficients were measured, the results shown were obtained.

The measurement conditions are: input rotation speed of the inertial body 165°r, p
ang,, moment of inertia of inertial body 0.058kf°a
az'', the measurement interval was 4 times/minute, and after 3000 clutch engagements, the measurement was stopped, the clutch was air-cooled to room temperature, and then the measurement was restarted.

In the figure, line a corresponds to the friction material obtained using the material of the present invention, and ? ta b * Ce cl is Comparative Example I~■
These apply to friction materials obtained using the following base materials.

As is clear from the drawings, the friction material using the base material of the present invention shown in line a has a larger friction coefficient than that using the comparative base material shown in lines b-d, and the value is The number of times the clutch is engaged and engaged increases, so even if the temperature of the friction material increases, it remains approximately constant, providing excellent friction performance.

C6 Effects of the Invention According to the present invention, the above-mentioned 5Ke standard cellulose fiber, polyamide U&fiber, glass! By blending fibers and a friction performance improver, the wet papermaking properties of the paper product can be improved, and a base material for an IQ drilled nail material can be provided, which reduces production efficiency.

Further, by using the base material, it is possible to obtain a friction material that has excellent friction performance, has high rotational fracture strength, and does not contain asbestos and therefore does not cause pollution problems.

[Brief explanation of the drawing]

The drawing is a graph showing the relationship between the number of clutch engagements and friction coefficients in friction materials obtained from the present invention base material and the comparative example base material. Patent applicant F.C.C. Co., Ltd. Agent
Patent Attorney Ken Ochiai ′-）Dougai clutch intermittent rotation

Claims (1)

[Claims] Cellulose fiber 5-30% by weight, polyamide fiber 2
-30% by weight, 2 to 20% by weight of glass fibers, and 30 to 80% by weight of a friction performance improver, and a wet paper-made paper product; a phenolic resin impregnated into the paper product;
Base material for friction materials.