JPS59109595A - Lithium soap grease composition with improved load resistance and abrasion resistance - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to improved 7I-1 lubricant compositions and, more particularly, to the addition of antimony dialkyldithiocarbamates and selected borate compounds or borate compounds. The present invention relates to a lithium soap grease composition containing a combination of agents and having improved load carrying and wear resistance.

BACKGROUND OF THE INVENTION It is well known in the art that a variety of metallic soaps can be used with advantage in preparing lubricating greases from virtually any lubricating oil base stock and that the greases thus prepared generally exhibit good grease properties. It is. Although a number of grease compositions have been produced using various combinations of metallic soap thickeners and base oils, they have not been used in severe applications where high load carrying capacity and low abrasion properties must be simultaneously satisfied. There have been particular difficulties in obtaining grease compositions suitable for One such application relates to the operation of constant velocity joints used in automotive production, which involve vibratory motion under high loads and severe conditions such as sliding and rolling.

Some examples of known grease compositions that have been used for a variety of applications include U.S. Patent No. 5,758.40.
7, 3.791.975 and 3.929.
Examples include lithium soap greases such as those exemplified in US patents such as No. 651.

Also, for example, “Modern Lubricatin
G Greases” (C.G. Bonner, 19
A number of additives have also been disclosed for imparting various properties to grease compositions, as exemplified in 76, K., 51-5, p. 6). , including metal dithiocarbamates as extreme pressure additives, as well as numerous other extreme pressure additives and antiwear additives.
U.S. Patent No. 2.81'2,306 and the same cylinder 3,8
No. 01.50jS discloses grease compositions containing metal dithiocarbamates and other additives to satisfy properties such as rust and copper corrosion. Historically, US Pat. No. 4,100,080 discloses a grease composition containing a dispersion of potassium borate as an extreme pressure additive.

Many 4. Although numerous grease compositions have been developed, there is a continuing need for high performance greases that provide the requisite high load capacity and low abrasion required for certain applications.

SUMMARY OF THE INVENTION According to the present invention, when an additive combination of antimony dialkyldithiocarbamate and a selected borate compound or agglomerate is blended, a surface-running grease composition having improved high load performance and low wear property is provided. It was found that it was provided.

More specifically, the present invention is a lubricating grease composition comprising a majority of a 41j lubricant base stock and from about 2 to about 50% by weight of a thickener system, wherein the thickener system has a CWt to Cta
Hydroxy fatty acid lithium soap and about 0.01 ~
An additive combination of about 10:00 weight percent antimony dialkyldithiocarbamate (each alkyl group having 1 to 22 carbon atoms) and about 0.001 to about 10 weight percent potassium or sodium or boric acid. The present invention relates to a lubricating grease composition comprising:

As previously described, the present invention relates to lithium grease compositions containing an additive combination of fugitive antimony dithiocarbamate and selected borate compounds or boric acid and exhibiting improved high load and low wear properties. .

The antimony dithiocarbamate that can be used in the present invention generally has the following formula (%) [wherein each R is an alkyl group having 1 to 22 carbon atoms and is an antimony dialkyldithiocarbamate which can be represented by an integer from 6 to 5 depending on the valence.

Preferred dithiocarbamate compounds include each R from 1 to 1.
8 is preferably alkyl having 3 to 15 carbon atoms and such that X is 3. This 11■
A large number of dithiocarbamate salts are available on the market, and a number of such compounds and methods for their preparation are available from Ency.
c I opediof Chemical Tecb
” (Kirk-Qthmer, 2nd edition,
1968, Vol. 17, pp. 513-514). Also, for additional disclosure of compounds and their preparation, see 'Lubricant Add
tives' (C1V, Smalheer et al., 19
67, p. 6) and U.S. Patent No. 2.450. /i
33, 2.492.3 f 4 and 2.5
80.274.

Certain selected monoborate or boric acids can be used as the second component in the additive combinations used in the present invention. The salt compounds may be alkali metal borates, with potassium and sodium being preferred and potassium (most preferred). It has many different forms such as salts and pentaphosphates. As used herein, the term ``acid acid compound'' refers to all such forms of G.
i Includes phosphates. Additionally, a description of the borate compounds and borate compounds and methods of their preparation can be found at pncy.
clopedia of Che+n1cal Tec
hnology” (Kirk-Othmer, 2nd
Edition, 1968, Vol. 3, pp. 608-652) and “Advanced Inorganic Chemi.
stry” (F, A, Cotton and G, Wilk
inson, 1966, pages 262-266).

As noted above, a particularly preferred borate compound is potassium borate, and such compounds generally have the empirical formula % or the formula O.yB,03.xH,0 [where y is about 2 to about 5, preferably about 2.5 to about 4
．． 5, more preferably about 2.5 to about! is a positive number of L5,
and X has a hydrated form having a number of from about 1 to about 9, preferably from about 2 to about 48, more preferably from about 2.8 to about 4.4. The particularly most preferred value for y is 3.

In describing the above compositions, the number y represents the y-to-potassium ratio, v11, or the number of parts per part of potassium.

One particularly useful potassium borate of the above filts is
U.S.A. No. 199Z454 and No. 4.100.0
80, a water/oil emulsion of an aqueous solution of potassium hydroxide and boric acid is dehydrated to give 2.5 to 4.
Potassium borate dispersion prepared by boron to potassium ratio of 5. This production is
An aqueous solution of potassium hydroxide and boric acid (potassium borate solution) and preferably an emulsifier are introduced into an inert non-polar oil medium, the mixture is vigorously stirred to form an emulsion of the aqueous solution in oil, and then This is carried out by heating at a temperature and time that provides the desired degree of hydration and microemulsification. The average particle size of potassium oxalate is generally 1
smaller than a micron.

Another method of preparing potassium oxalate dispersions involves reacting an oil-soluble alkali or alkaline earth metal sulfonate overbased with potassium carbonate with boric acid.

A useful bovine salt composition is one dispersed in combination with the previously described US Pat.

The thickener system used in the grease compositions of the present invention contains lithium soaps of hydroxy fatty acids. The hydroxy fatty acids used in preparing the greases of the present invention preferably have from about 12 to about 24 carbon atoms, and preferably from about 16 to about 20 carbon atoms.

Preferred hydroxy fatty acids for raw materials include hydroxystearic acid such as 9-hydroxy, 10-hydroxy or 1
2-hydroxystearic acid, and more preferably the latter. It is also possible to use ricinol 1'e, which has a bimodal bond at the 9-1° IY position, which is the unsaturated form of 12-hydroxystearic acid.

Other useful hydroxy fatty acids include 12-hydroxybehenic acid and 10-hydroxypalmitic acid.

The lithium soap thickener used in the present invention may consist of a complex of hydroxy fatty acid lithium soap and oxalic acid paste soap.

A second hydroxycarboxylic acid can be used in conjunction with oxalic acid and a hydroxy fatty acid. This is generally
It has an OH group attached to no more than 6 carbon atoms from the carboxyl group. The acids have about 3 to about 14 carbon atoms and include lactonic acid, 6-hydroxydecanoic acid, 3-hydroxybutanoic acid, 1-human tetraxycaproic acid, 4-hydroxybutanoic acid, 6-hydroxy −α−
Fatty acids such as hydroxystearic acid, or parahydroxybenzoic acid, salicylic acid, 2-hydroxy-4-hexylbenzoic acid, metahydroxybenzoic acid, 2,5-dihydroxybenzoic acid (gentisic acid), 2. (benzoic acid such as S-dihydroxybenzoic acid (r-resorcylic acid), 4-hydroxy-4-methoxybenzoic acid, or hydroxyl acid such as orthohydroxyphenyl, metahydrogysiphenyl, or haharahydroxyphenylacetic acid) It may be any of the aromatic fatty acids.Also, Schiff tetraaliphatic oxycarboxylic acids such as hydroxycyclopentylcarboxylic acid or hydroxynaphthenic acid may be used.Particularly useful oxycarboxylic acids include lactonic acid, salicylic acid and para- It is hydroxybenzoic acid.

Instead of using free oxycarboxylic acids of the latter type when preparing greases, lower alcohol esters such as the methyl, ethyl, propyl, isopropyl or dibutyl esters of said acids such as salicylic acid A/methyl acid can be used to make the salt insoluble. A good dispersion can be produced when .

The lithium grease composition used in the present invention also includes at least one lithium soap that is MIJ'Xed from a fatty acid containing functional groups such as hydroxy groups, epoxy groups, and ethylenically unsaturated groups, and a dicarboxylic acid. From iU'
4' may also be included in combination with at least one camphor dilithium soap.

Hydroxy or epoxy 1! When a fat reduction is used, it generally has the following structural formula: % [where R in either formula is H or a carbon atom containing from about 1 to about 27 carbon atoms] and n is an integer within the range of 0 to 27. The total number of carbon atoms in both R and (CH,)n is from about 5 to about 27, so when R contains 27 carbon atoms this must be zero, and when n is 27 It is understood that at some times R must be H. A preferable long body is
1, n is in the pq4 range from 7 to 13, thus providing a hydrocarbon group containing about 7 to 4j13 carbon atoms, and R is H or about 1 to about 10 carbons. It is either an i-chain containing atoms or a branched hydrocarbon group. In the most preferred embodiment, n is 7 and R is a straight hydrocarbon agent containing 8 carbon atoms.

On the other hand, ethylenically unsaturated fatty acids useful in the present invention generally have the structural formula % [in the above formula, R, independently from the same group as R in the formula described above]. and m is 4 from 0 to 27 in the same manner that n in the previous formula can be from 0 to 27.
・r number]. Similarly, R1 and m are subject to all other limitations set forth in the previous equation descriptions for R and n, which also apply to the preferred scoop and the most preferred float.

A second hydroxycarboxylic acid can also be used with a lithium soap derived from a functional group 1l-1 (:1 fat β?) and a dilithium soap derived from a dicarboxylic acid. is maximum 13~ff,'';1
01(
It has a group.

9-110- and 12-hydroxysterolyl alcohols which can be used as base thickeners in combination with the dilithium component include 9-110- and 12-hydroxysterolyl
+'! , 12-hydroxybenzene, and 10-hydrocybalmitic acid. Epoxy-substituted fatty acids that can be used include 12゜13-epoxystearic acid, 15,16-epoxystearic acid, 19,
Mention may be made of 10-epoxystearic acid and 9,10-epoxypalmitic acid. Similarly, ethylenically unsaturated fatty acids that can be used include oleic acid, linoleic acid, linoleic acid, and palmitoleic acid.

The dicarbond gases that can be used in the greases of the invention have a carbon atom number of μI4 to F112, preferably about 6 to #-+10 carbon atoms. As for cape, amber, glutaric acid, adipic acid, speric acid,
Examples include valmitine, azelain, dodecanedioic acid, and sebacine. Sebacic acid and azelaic acid are preferred.

Particularly preferred lithium greases are lithium complex greases, and in particular complexes of lithium soaps of hydroxy fatty alcohols and lithium soaps of hydroxyl fat fermentation and dicarboxylic (5 ) with dilithium soap.

Lithium grease compositions of the type described above are disclosed in U.S. Pat.
U.S. Patent No. 5,791.97, issued February 12, 1974.
No. 3 and U.S. Patent No. 3, issued October 12, 1976.
．． No. 985.662. These patents contain 21M! You can find out how to make it and its details.

l+ used in preparing the grease composition of the present invention
The i11 fFt oil-based raw material F1 may be any of 11(jcommonly used mineral η)1, synthetic hydrocarbon soybean oil, or synthetic ester oil. Generally, these drops are 21
The mineral lubricant-based mortar used to prepare greases is composed of paraffin threads, naphthenic and hybrid ring fills. Synthetic lubricants that can be used include esters of dibasic FI U such as di-2-ethylhexyl sebacate, C13 oxoacid diesters of tetraethylene glycol, etc. or complex esters such as those formed by 1 mole of sepacic acid, 2 moles of tetraethylene glycol and 2 moles of 2-ethylhexyl. Oils include synthetic hydrohydrogens such as argylbenzenes, e.g. alkylate bottoms from the alkylation of benzene with tetrapropylene or polymers and copolymers of alpha-olefins, silicone oils e.g. ethylphenylbolysiloxane, methyl Polysiloxanes and polyglycols, such as those obtained by condensing butyl alcohol with propylene oxide, carbonate esters, such as those obtained by condensing butyl alcohol with propylene oxide, and carbonate esters, such as C8 oxo alcohols, are reacted with carboxyl ethyl to form half esters, which are then converted into tetraesters. Examples include products obtained by reacting with ethylene glycol. Other suitable synthetic oils include polyphenyl ethers, such as those having about 3 to 7 ether bridges and about 4 to 8 phenyl groups. See column 3 of 1).

Total lithium soap content in the grease composition of the present invention1.
is within the range of about 2% to about 30% by weight, preferably about 5% to about 20% by weight, based on the total composition. This also applies when using more than one type of lithium soap. The amount of antimony dithiocarbamate ranges from about 0.01 to about 110%, preferably from about 0.1 to about 5% by weight of the total composition.

The amount of borate or boric acid selected is approximately 0.0% of the total composition.
0.1 to about 10% by weight, preferably about 0.1 to about 5% by weight.

The grease compositions of the present invention may be prepared according to any of the techniques known in the art, and such compositions may include other additive components normally found in grease compositions, such as dyes, antioxidants, etc. , corrosion inhibitors, lubrication enhancers, etc. may also be included.

As previously mentioned, the grease compositions of the present invention are particularly useful in high performance operations where high load requirements and low wear are essential. One particular application where such flat performance characteristics are required is in the lubrication of fixed joints found in automotive powertrains.

The blowing examples are provided to illustrate the invention and should not be construed as limiting the invention.

Example 8 4.3 parts by weight of mineral oil and 6.4 parts of 12-droxystearic acid and 119 parts by weight of azelaic acid and 144 parts by weight
A lithium complex soap grease was prepared using a thickener system consisting of a combination of 30% and 30% lithium hydroxide hydrate. The American company Chevron Co., Ltd. has given the product name r to the grease manufactured by S.
3.0 parts by weight of a potassium borate oil dispersion commercially available under Q1oa 9750j and 2.0 parts by weight of cyamyl dithiocarbaminated antimony were added, as well as conventional corrosion inhibitors, antioxidants and dyes.

The prepared grease has a dropping point below 485 and 0 at 60 strokes.
) 500 mm/10 (1:) Penetration (77'F
ASTM D217), and when micro-wear is measured, it is 4.
．． 8, and the standard Timken load test (ASTM D
2501) to pass a 60 lb load and 50 kl
,, 0.45 at 1800 rpms 1 hr, 75°C
mm four-ball wear (ASTM D-2266) and had a four-ball EP@heavy wear index of 42.3 ky and a seizure charge of 315 kP.

These results demonstrate good load-carrying capacity of the grease compositions of the present invention as well as low wear on vibration or reciprocating motion as shown by the four-ball test and micro-wear.

For comparative purposes, a commercially available lithium 12-hydroxystearate thickener grease of similar quality, but without the additive combination of borate and antimony tribamate, was found to have a 5.5 m 90) @ moving floor. Wear, 40
1b 0)-f-mukengo I'r! Kyoto, 40kyS12
00 rpms 1 hour at 75°C (L57mm four-ball abrasion (ASTM D-2266), 49, @
The four-ball EPWt heavy wear index and 60ky seizure had a load.

These results demonstrate the improved high load and low wear properties of the grease compositions of the present invention.

Claims (10)

[Claims] (1) Majority of the lubricating oil base material and about 2 to about 30% by weight
A lubricating grease composition comprising a thickener system of C1! - Lithium soap of C24 hydroxy fatty acids and about 0.01 to about 10% by weight antimony dialkyldithiocarnocuminate (each alkyl group having 1 to 22 carbon atoms) and about 0.01 to about 1% ON A lubricating grease composition comprising an additive combination of potassium or sodium borate or boric acid. (2) The grease composition according to claim 1, wherein the balate compound is potassium borate. 3. The grease composition of claim 2, wherein the potassium oxalate has a boron to potassium ratio of about 2 to about 5. (4) The grease composition according to claim 5, wherein the thickener system is a lithium soap. (5) The lithium soap thickener is a complex of lithium soap of hydroxy fatty acid and lithium boric acid or a complex of lithium soap of hydroxy fatty acid and dilithium soap of linear dicarboxylic acid having 4 to 12 carbon atoms. A composition according to claim 4. 6. The composition of claim 4, wherein from about 0.1% to about 5% by weight of the dithiocarbamate compound is used and from about 0.1% to about 5% by weight of potassium borate is used. (7) Each alkyl group in the dithiocarbamate is 1
7. The composition of claim 6 having ~18 carbon atoms and a boron to potassium ratio in the potassium borate of from about 2.5 to about 4.5. (8) The thickener system is derived from at least one lithium soap derived from a fatty acid containing a functional group selected from the group consisting of hydroxy, epoxy and ethylenically unsaturated groups, and a linear dicarboxylic acid. 8. A composition according to claim 7, comprising at least one dilithium phosphorus. 9. The composition of claim 7, wherein the salt salt is a hydrated potassium balate dispersion having an average particle size of less than 1 micron. (10) Scope of Patent Requested by Nif A method for lubricating a constant speed joint of an automobile power train to provide high load resistance and low wear resistance, the method comprising using the grease composition described in item 1 as a lubricant. .