JP2829619B2 - Brake lubricant - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a lubricant used for an automobile, and more particularly to a silicone-based lubricant used for a brake system in general.

[Related Art] Grease for brake rubber, which has been used as a conventional lubricant grease for a brake system, is generally composed of a synthetic oil base oil and a thickener mainly composed of lithium soap.

In addition, as a lubricant used outside the transmission mechanism of the operating force, so-called brake grease, a grease composed of a mineral or synthetic base oil and a metal or mineral filler is generally used. .

Although brake rubber grease and brake grease are often used at the same time when repairing automobiles and adjusting brake parts, it is difficult to use the same composition for the required properties and performance of both. In addition, there is a trouble in that several types of greases are prepared and used depending on the purpose.

The brake system lubricants must pass the JIS-K-2228 type 2 lubricant and JASO-M308 type 1 and type 2 lubricant standard tests. There was no lubricant that passed all of the above, and there was the inconvenience of using a plurality of lubricants properly according to the place of use and application.

Among the known lubricants for brakes, silicone lubricants containing silicone oil and lithium soap as main components have been expected to be used in the entire brake system of automobiles due to their excellent properties. Of these, those that do not pass the JIS-K-2228 Class 2 lubricant standard test established last year.

[Problems to be Solved by the Invention] In view of the above circumstances, an object of the present invention is to provide a brake lubricant composition that can be used in the entire brake system of an automobile. Another object of the present invention is to provide a novel silicone lubricant for brakes having a characteristic of passing the JIS-K-2228 Class 2 lubricant specification test which is a problem of the brake lubricant of the above.

Means for Solving the Problems The present invention relates to a non-mineral oil-based lubricant used for a sliding part of a transmission device and a control device of a brake system of an automobile, wherein the main components are a silicone oil and a quaternary ammonium salt. A brake lubricant comprising bentonite treated with an organic kaolin activator comprising

As the silicone oil which is one of the essential components of the brake lubricant of the present invention, a conventionally known silicone base oil can be appropriately used. Specifically, besides typical polymethylphenyl-dimethylsiloxane copolymers, polydimethylsiloxa, polymethylphenylsiloxane and the like can be used.

A feature of the present invention resides in the use of bentonite treated with an organic quatinic activator comprising a quaternary ammonium salt as a thickener to be combined with a silicone base oil. Examples of these are Toyobo Junko's products Esven, Esven 74,
Nationallead Co. Products Benton, Southwest Grease
and oil Co. products bentorub can be exemplified, but in general, bentonite treated with a quaternary ammonium salt having a linear alkyl group having 16-18 carbon atoms has the general formula Compounds that can be represented as (R is a straight-chain alkyl group) are preferred.

The proportion of the silicone base oil and the selected thickener is preferably 50 to 90 parts by weight, and the latter is preferably 10 to 50 parts by weight.

The lubricant for brakes of the present invention may contain an appropriate amount of an antioxidant, a rust preventive, an oiliness improver, and the like according to the purpose.

As an example of the method for producing the grease of the present invention, a thickening agent consisting of bentonite treated with an organic quatinic acid activator consisting of a quaternary ammonium salt, a silicone base oil and, if necessary, a rust inhibitor, an antioxidant, After adding an oiliness improver and the like and stirring and mixing, preferably, an organic solvent such as acetone and isopropyl alcohol is added in an amount of about 1 to 10 parts by weight with respect to the total weight and, after stirring until the mixture is generally homogeneous, filtration, deaeration, The desired grease-like lubricant can be obtained by homogenizing.

[Effect of the Invention] A lubricant composed of a silicone-based base oil and lithium soap, which is conventionally considered to be the best, is immersed in a rubber cup made of SBR for brakes in accordance with the standard test method of JIS-K-2228. When left in a 120 ° C. atmosphere for 70 hours, the silicone base oil and the lithium soap as a thickener react with the rubber to be lubricated to form foreign substances (reactants) on the surface. No foreign matter is formed on the rubber surface even when subjected to the same test. The lubricant of the present invention simultaneously passes two other standard tests.

It is surprising that replacing the lithium soap with the selected thickeners of the present invention produces such a significant difference in effectiveness in combination with a silicone base oil. As described above, a single type of grease can provide performance that can be used for the entire brake system and can provide a lubricant that conforms to the standard, thereby improving workability and preventing deterioration of the lubrication performance due to a lubricant mistake. The effect is extremely large.

[Examples] The present invention is illustrated below by Examples and Comparative Examples.

Examples 1 to 4 Brake lubricant compositions having the following essential components were prepared.

1.Polydimethylphenylsiloxane copolymer 50cs ・ ・ ・ 60 parts by weight Esven ・ ・ ・ 40 parts by weight 2.Polydimethylmethylphenylsiloxane copolymer
125cs ... 70 parts by weight Esben 74 ... 30 parts by weight 3.Polymethylphenylsiloxane 500cs ... 85 parts by weight Esven ... 15 parts by weight 4.Polydimethylsiloxane 150cs ... 60 parts by weight Esven 74 ・··· 40 parts by weight Comparative Examples 1 to 6 As a comparative example, a lithium soap-based silicone grease that has been used as a brake-based grease without any practical problems has been compared with the present invention.

The lithium soap-based silicone grease blended as a comparative example was prepared by mixing lithium soap and silicone base oil with stirring, heating and stirring to 200 ° C., and cooling to obtain a desired blend.

1.Polydimethyl methylphenylsiloxane copolymer
50cs ・ ・ ・ 65 parts by weight Lithium stearate ・ ・ ・ 35 parts by weight 2.Polydimethyl-methylphenylsiloxane copolymer
125cs ... 80 parts by weight Lithium stearate ... 20 parts by weight 3.Polymethylphenylsiloxane 500cs ... 85 parts by weight Lithium stearate ... 15 parts by weight 4.Polydimethylsiloxane 150cs ... 70 parts by weight Lithium stearate: 30 parts by weight 5. Toray Silicone SH45 6. Shin-Etsu Chemical G-40M Evaluation Test SBR rubber cup is immersed in each composition and 120
After being left in an atmosphere at 70 ° C. for 70 hours, the rubber cup was taken out, and the presence or absence of a precipitate on the surface was examined.

 The results are shown in the following table.

As a result, it was found that the composition according to the present invention did not generate any precipitate on the surface.

In comparison, it was confirmed that a precipitate was generated under the same conditions for all of the comparative examples.

The composition according to the invention also passed the JASO-M308 Type 1 and Type 2 lubricant specification test.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ identification code FI C10N 50:10 (58) Investigated field (Int.Cl. ⁶ , DB name) C10M 113 / 16,107 / 50,119 / 22,115 / 08 C10N 5 :Ten

Claims (1)

(57) [Claims] 1. A non-mineral oil-based lubricant used for a sliding portion of a transmission system and a control system of a brake system of an automobile, wherein a main component is a silicone-based oil and an organic cation activator comprising a quaternary ammonium salt. A lubricant for a brake, comprising a treated bentonite.