JP3428546B2 - Anti-rust grease - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rust preventive grease, and more particularly to a rust preventive grease suitable for cast iron and the like used in automobile brake or clutch systems.

[0002]

2. Description of the Related Art Wheel sliding units, master cylinders, pistons and cylinder bodies in disc brakes and the like are examples of sliding parts of a brake system of an automobile. For the strength of the cylinder body, an aluminum casting is used from the viewpoint of friction characteristics and weight reduction, but in the case of a large vehicle, cast iron or the like is also used.

[0003]

However, even cast iron or the like has a drawback that it is easily rusted. For example, as known from Japanese Examined Patent Publication No. 61-13518, soft iron (SPCC) and the like exhibit excellent rust-preventive properties even when subjected to a wet test or a salt water test, but in the case of cast iron or the like. However, good rust resistance cannot be obtained. In addition, since the grease used for the sliding portion of the brake may come into contact with rubber, its influence on rubber must be small.

The present invention has been made by paying attention to such a conventional technique, and provides a rust preventive grease exhibiting excellent rust preventive properties without impairing basic performance such as influence on rubber. To do.

[0005]

Then, the inventor has come to discover the present invention as a result of repeated research for achieving the above-mentioned object. That is, the rust preventive grease of the present invention comprises 100 parts by weight of polyoxypropylene glycol monoalkyl ether which is a base oil, 3 to 30 parts by weight of fatty acid metal soap which is a thickener, and component A (which is a rust preventive agent). The total amount of the aliphatic dicarboxylic acid) and the component B (ethanolamine) is 0.1 to 10 parts by weight.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION As a base oil, 100 polyoxypropylene glycol monoalkyl ether is used.
Includes parts by weight. Polyoxypropylene glycol monoalkyl ether has optimum rubber swelling property, excellent low temperature fluidity, heat resistance, water resistance, and compatibility with brake fluid. This polyoxypropylene glycol monoalkyl ether has a kinematic viscosity at 100 ° C. of 10 to 100 mm.
It is preferably about ² / S. If the kinematic viscosity is less than 10 mm ² / S, the amount of grease evaporation increases and the heat resistance deteriorates. When it exceeds 100 mm ² / S, the viscosity at low temperature becomes too high. The polyoxypropylene glycol monoalkyl ether is preferably an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a pentyl group and a hexyl group.

The thickener contains 3 to 30 parts by weight of fatty acid metal soap (preferably 5 to 25 parts by weight, more preferably 7 to 20 parts by weight). When it is less than 3 parts, the grease is too soft to be washed away from the used part, and when it is more than 30 parts, the grease is too hard and the operating torque is increased, so that it is not suitable. The fatty acid metal soaps are known per se, and specific examples thereof include metals of organic acids such as 12-oxystearic acid, lauric acid, myristic acid, palmitic acid, stearic acid, oleic acid, and linoleic acid. Examples of soap include calcium soap, lithium soap, aluminum soap, barium soap and the like. Especially 1
It is preferred to use lithium 2-oxystearate soap.

As the rust preventive, the total amount of the component A (aliphatic dicarboxylic acid) and the component B (ethanolamine) is 0.1 to 10 parts by weight (preferably 0.2 to 8 parts by weight, more preferably Is 0.3 to 6 parts by weight).
If both the component A and the component B are not contained, the desired rust preventive effect cannot be obtained. If the amount of the components A + B is less than 0.1 part, the rust preventive effect is small, and if it is more than 10 parts, the water resistance is deteriorated and a sufficient rust preventive effect cannot be obtained.

The aliphatic dicarboxylic acid which is the component A is 2 to
It has 12 preferably 4 to 12 and most preferably 6 to 10 carbon atoms. Examples of such an acid include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, suberic acid, pimelic acid, azelaic acid, dodecanedioic acid, and sebacic acid. Sebacic acid and azelaic acid are particularly preferred.

As the component B, ethanolamine,
Mono, di and tri can be used, but triethanolamine is particularly preferred.

In the grease of the present invention, in order to further improve its characteristics, various additives such as diphenylamine-based and high-molecular phenol-based antioxidants, benzotriazole-based and thiazole-based corrosion inhibitors, An appropriate amount of anti-friction agents such as molybdenum disulfide, graphite, tungsten disulfide, and nitrogen boron may be added.

[0012]

EXAMPLES Next, the grease of the present invention will be described with reference to Examples and Comparative Examples.

Example 1 15.0 parts of 12-oxystearic acid and 50 parts of polyoxypropylene glycol monobutyl ether were charged in a saponification kettle and heated to 90 ° C. to uniformly dissolve them. To this was added 2.3 parts of lithium hydroxide adjusted to a 5-fold aqueous solution with water, and the mixture was saponified and dehydrated. Then, after the temperature was raised to 130 ° C., 50 parts of the remaining polyoxypropylene glycol monobutyl ether was added, and the mixture was further heated to 170 ° C. and sufficiently stirred and mixed. After cooling this to 120 ° C. with a stirring cooler, 2.0 parts of diphenylamine-based antioxidant,
Sebacic acid (component A) (0.2 parts) and triethanolamine (component B) (0.3 parts) were added, thoroughly stirred and mixed, cooled to room temperature, and uniformly kneaded with a roll mill to prepare a brake grease composition. Got

Then, various physical properties of the obtained grease were tested. The test items and test methods are as follows.

Consistency: According to JIS K2220 section 5.3. Dropping point: According to JISK2220 section 5.4. Evaporation amount: According to JISK2220 section 5.6. Oil separation degree: According to JISK2220 section 5.7. Oxidation stability: According to JISK2220 section 5.8. Rubber swelling: According to JIS K2228 section 8.10. Wetness: According to JISK2220 section 5.17. However, the test piece uses a plate of gray cast iron (FC20 specified in JIS G5501), and the time when rust occurs (A
Test). Salt spray: According to 5.3 of JISK2246. However, the test piece uses a plate of gray cast iron (FC20 specified in JIS G5501), and the time when rust occurs (A
Test).

Examples 2 to 6 The combinations of the component A (azelaic acid / sebacic acid) and the component B (triethanolamine), which are the rust preventives of the present invention, were changed as shown in Table 1 of FIG. 2-6 greases were obtained. Regarding the component A of the rust preventive agent of the present invention, other than azelaic acid and sebacic acid were also carried out, and regarding component B, monoethanolamine and diethanolamine were also carried out, but almost the same results were obtained. Therefore, the description is omitted in Table 1 of FIG.

Comparative Examples 1 to 10 Either only component A or component B in the rust preventive agent was added (Comparative Examples 1 and 2), or an alkenyl succinamide amide other than the present invention was used as the rust preventive agent. Petroleum sulfonic acid C
a salt, dinonylnaphthalenesulfonic acid Ba salt, phosphoric acid ester amine salt, rosin amine salt, and lanolinic acid Ca salt (Comparative Examples 3 to 8) to obtain grease as a comparative example shown in Table 1 of FIG. It was

As is clear from Table 2 of FIG. 2 showing the test results, Example 1 in which the components A and B of the rust preventive agent were simultaneously added
The greases of ~ 6 showed very good rust resistance in the wet test and the salt spray test. Also, the consistency,
It also had basic performance such as dropping point, evaporation, oil separation, oxidation stability, rubber swelling, etc. as a grease used for automobile brake related parts. On the other hand, Comparative Examples 1 to 8 have extremely poor rust preventive properties, although the basic performances other than rust preventive properties are the same as those of the Examples. Comparative Example 1,
In No. 2, even if the rust preventive agent equivalent to the present invention is used, sufficient rust preventive property is not obtained because the component A or the component B is added alone. In Comparative Example 9, the component A and the component B are added at the same time, but the total amount thereof is less than 0.1 part, so a sufficient rust preventive effect cannot be obtained. In Comparative Example 10 as well, the components A and B were added simultaneously, but since the total amount was more than 10 parts, the water resistance was poor and a sufficient rust preventive effect could not be obtained.

[0019]

INDUSTRIAL APPLICABILITY The present invention has basic performances such as a small adverse effect on rubber, which is one of brake parts, and is rustproof against cast iron or the like, which is the material of the cylinder bodies of wheel cylinders and master cylinders. Excellent grease.

[Brief description of drawings]

FIG. 1 is a table 1 showing components of Examples and Comparative Examples.

FIG. 2 is a table 2 showing test results of examples and comparative examples.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI C10M 129: 42 C10M 133: 08 133: 08) 129: 10 (C10M 169/00 C10M 133: 12 107: 34 C10N 10:02 117 : 02 10:04 129: 10 10:06 129: 34 30:12 129: 42 40:02 133: 08 50:10 133: 12) C10N 10:02 10:04 10:06 30:12 40:02 50 : 10 (72) Inventor Yoshinari Ito 10 Wakamicho Road, Toyota City, Aichi Prefecture, Hosei Break Industry Co., Ltd. (72) Inventor, Suzuki Kohiro, Wakaicho Road, Toyota City, Aichi Prefecture, Hosei Break Industry Co., Ltd. Incorporated (72) Inventor Takeshi Tomino 4-9-25 Shibaura, Minato-ku, Tokyo Cosmo Oil Lubricants Co., Ltd. (56) Reference JP-A-64-29496 (JP, A) JP-A-63-309591 ( JP, A) JP 4-266995 (JP, A) JP 56-49800 (JP, A) JP 63-168493 JP, A) JP Akira 58-31086 (JP, A) JP flat 3-240981 (JP, A) (58 ) investigated the field (Int.Cl. ^7, DB name) C10M 169/00 - 169/06 C10M 107/34 C10M 117/02-117/04 C10M 129/10-129/14 C10M 129/34 C10M 129/42 C10M 133/08 C10M 133/12-133/14 C10N 10:02-10:06 C10N 30 : 10-30:12 C10N 40:02 C10N 50:10 C23F 11/12-11/14

Claims (6)

(57) [Claims] 1. A base oil of 100 parts by weight of polyoxypropylene glycol monoalkyl ether, 3 to 30 parts by weight of a thickening agent of fatty acid metal soap, and a rust preventive component A (aliphatic dicarboxylic acid). And a rust preventive grease containing 0.1 to 10 parts by weight of component B (ethanolamine) in total. 2. The alkyl group of polyoxypropylene glycol monoalkyl ether is a methyl group, an ethyl group,
A propyl group, an isopropyl group, a butyl group, an isobutyl group, a pentyl group, or a hexyl group.
Anti-corrosion grease described. 3. Fatty acid metal soap is 12-oxystearic acid, lauric acid, myristic acid, palmitic acid,
The rust preventive grease according to claim 1 or 2, which is a metallic soap of stearic acid, oleic acid or linoleic acid. 4. The component A is any one of oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, suberic acid, pimelic acid, azelaic acid, dodecanedioic acid and sebacic acid. The rust preventive grease according to any one of items. 5. The rust preventive grease according to claim 1, wherein the component B is any one of monoethanolamine, diethanolamine and triethanolamine. 6. The rust preventive grease according to claim 1, which contains a diphenylamine-based antioxidant or a polymer phenol-based antioxidant as the antioxidant.