HIGH DROPPING-POINT LITHIUM-COMPLEX GREASE HAVING IMPROVED ANTI-NOISE PROPERTIES

Abstract: High dropping-point lithium-complex grease composition having improved anti-noise properties, comprising a lubricating oil and the following components: (a) at least one lithium soap selected from the group consisting of the lithium salts of C₁₀ to C₃₄ fatty acids and C₁₂ to C₂₄ hydroxy fatty acids, (b) at least one lithium salt selected from the group consist­ ing of the dilithium salts of C₄ to C₁₂ aliphatic dicarboxylic acids, the lithium salts of boric acids, and the lithium salts of aromatic hydroxy carboxylic acids, and (c) a high-molecular viscosity-index improver, and/or suc­ cinimide-type dispersant and/or metal salt detergent.

Description: HIGH DROPPING-POINT LITHIUM-COMPLEX GREASE HAVING IMPROVED ANTI-NOISE PROPERTIES The present invention relates to a high-quality lithium-complex grease composition having improved anti-noise properties, a high dropping point, a long lubrication life and an excellent oxidation stability also at high temperatures. High dropping-point lithium-soap greases are generally referred to as lithium-complex greases, and several of them are proposed so far (see e.g. US patent specifications 2,940,930, 3,223,624, 3,758,407 and 3,929,651). However, these lithiumcomplex greases were inferior in their anti-noise properties because of the low dispersancy in the base oils of the metal salts used for the formation of complexes with lithium soaps. The purpose of the present invention is to provide a lithiumcomplex grease composition having a long lubrication life, markedly improved anti-noise properties, a high dropping point, and an excellent oxidation stability also at high temperatures, by uniformly admixing and dispersing in a base lubricating oil a gelling agent (a), a complexing metal salt (b) and a dispersing component (c). This invention therefore relates to a high dropping-point lithium-complex grease composition having improved anti-noise properties, comprising a lubricating oil and the following components: (a) at least one lithium soap selected from the group consisting of the lithium salts of C10 to C34 fatty acids and C12 to C24 hydroxy fatty acids, (b) at least one lithium salt selected from the group consisting of the dilithium salts of C4 to C12 aliphatic dicarboxylic acids, the lithium salts of boric acids, and the lithium salts of aromatic hydroxy carboxylic acids, and (c) a high-molecular viscosity-index improver, and/or succinimide-type dispersant and/or metal salt detergent. The use of component (c) results into unexpectedly superior grease properties compared with the known greases which do not contain this component (c). Lubricating oil Any conventional lubricating oil can be used. While a typical one is a mineral oil, use can also be made, singly or in combination with the mineral oil, of a synthetic oil including ester oils, such as a diester oil, e.g. dioctyl azelate, and a tetra-ester oil, e.g. thepentaerythritol ester of an aliphatic monocarboxylic acid, or poly-alpha-olefin oligomers, such as octene-l/decene-l copolymers, having a viscosity of 41.0 cSt at 37.806, a viscosity index- (V.1.) of 130 and a flash point of 22300. The lubricating oil may have a viscosity ranging from about 2 to 500 cSt, preferably from 20 to 200 cSt, at 4000. Component (a) The C10 to C34 fatty acids include the saturated or unsaturated higher aliphatic monocarboxylic acids, especially those acids containing 16 to 22 carbon atoms, such as stearic acid and oleic acid. The C12 to C24 hydroxy fatty acids include saturated or unsaturated monocarboxylic fatty acids containing a hydroxyl radical, especially those acids containing 18 carbon atoms and a hydroxyl radical in the 9-, 10- or 12-position, such as 12-hydroxy stearic acid and ricinolic acid. The lithium salts of the above fatty acids and hydroxy fatty acids can be singly used or combinedly with one or more of others. In addition, when said lithium salts are prepared, said carboxylic acids can be reacted with lithium hydroxide not only in the form of free acids but also as glycerides. Component (b) Suitable C4 to C12 dicarboxylic acids used in the formation of the dilithium salt, are e.g. succinic acid, glutaric acid, adipic acid, suberic acid, pimelic acid, azelaic acid, dodecane dionic acid and sebacic acid. Acids containing 6 to 10 carbon atoms, especially adipic acid, sebacic acid and azelaic acid, are preferred. The lithium salts of boric acids can be used in place of or in combination with said dilithium salt or the other lithium salt. Suitable boric acid salts are lithium metaborate, lithium tetraborate lithium pentaborate, lithium perborate and the monolithium salt of ortho boric acid (H3BO3). The lithium salt of an aromatic hydroxy carboxylic acid can be used in place of or in combination with the above components (b). Suitable acids have the formula: EMI3.1 wherein R is a hydrogen atom or a hydroxyl, lower alkyl or lower alkoxy radical. Such acids include p-hydroxy benzoic acid, salicyclic acid (o-hydroxy benzoic acid), 2-hydroxy-4-hexyl benzoic acid, m-hydroxy benzoic acid,'2,5-dihydroxyl benzoic acid (gentisic acid), 2,6-dihydroxyl benzoic acid (y-resorcylic acid) and 4-hydroxy-3-methoxy benzoic acid. Salicylic acid is preferred. Incidentally, the hydroxyl radical (OH) in said lithium salt can he present in its free state as well as in the form of -OLi. Component (c) This component is used for the acceleration of the fine dispersion of the components (a) and (b) in the base oil, and the high-molecular VI-improver, succinic-imide type dispersant and metal salt detergent can be employed singly or rombinedly with one or more of other ones. Suitable high-molecular VI-improvers are oil-soluble highmolecular compounds having a mean molecular weight of about 1,000 to 1,500,000 in general, preferably about 2,000 to 300,000, and they reduce the temperature-dependency of the oil viscosity. Any of the conventional VI-improvers can be used, such as: : (1) polyisobutylenes, especially, those of the mean molecular weights in the range from 1,000 to 300,000; (2) homopolymers and copolymers of Cl tD C18 alkyl methacrylates, especially those of the mean molecular weights in the range from 20,000 to 1,500,000; (3) copolymers of C4 to C18 alkyl methacrylates with acryl or methacryl monomers represented by the general formula, EMI4.1 wherein R is a nydrogen atom or methyl radical and X means a polar radical, such as; EMI4.2 wherein Rr represents a C1 to C10 alkyl radical and n is an integer from 1 to 8, especially those of the mean molecular weights ranging from 20,000 to 1,500,000; (4) polymers or copolymers of one or more C1 to C18 alkyl acrylates, especially those of the mean molecular weights ranging from 20,000 to 1,500,000; ; (5) hydrogenated styrene-butadiene copolymers, especially those of the mean molecular weights ranging from 20,000 to 250,000 and styrene contents ranging from 25 to 70 weight Z; (6) hydrogenated styrene-isoprene copolymers, especially those of the mean molecular weights ranging from 20,000 to 250,000 and styrene contents ranging from 20 to 65 weightZ; (7) ethylene-propylene copolymers. especially those of the mean molecular weights ranging from 20,000 to 250,000 and ethylene contents ranging from 10 to 50 veight Z; (8) esters or asides of styrene-maleic acid copolymers; and (9) polyethylenes, especially those of the nun molecular weights ranging from 5,000 to 300,000. Among these oil-soluble bigh-molecular compounds, particularly preferred are those methyl-methacrylate polymers of tbe nun molecular weights ranging from 100,000 to 200,000, hydrogenated styrene-butadiene copolymers of the menn molecular weignts ranging from 80,000 to 160,000 hydrogenated styrene-isoprene vopoly- mars of the mean Molecular weights ranging from 80,000 to 160,000, ethylene-propylene copolymers of the mean molecular weignts ranging from 80,000 to 160.000 and nurtures of then. Suitable succinimide type dispersants are synthezised by reaction of polysidnes with the polybutenyl succinic anhydrides obained by the reaction of polybutenes and maleic anhydride. They include those dispersants represented respectively by the follo- wing formulae: EMI5.1 EMI6.1 wherein A1 denotes a C30 to C200 polyisobutenyl radical, p means an integer from 2 to 8 and q represents an integer from 1 to 8. Suitable metal salt detergents include sulphonates, phenates, phosphonates and salicylates represented respectively by the following formulae: (i) Sulphonates EMI7.1 wherein A2 and A are respectively a hydrogen atom or C8 to C30 alkyl radical, Ar means a benzene ring or naphthalene ring, M represents an alkaline earth metal, such as Ca, Ba or Mg, and M means an alkali metal, such as Na, K or Li (ii) Phenates EMI7.2 wherein A3 is a C4 to C16 alkyl radical, Ml means an alkaline earth metal, such as Ca, Ba or Mg, and x represents an integer, 1 or 2. (iii) Phosphonates EMI7.3 wherein A4 means a C30 to C200 polyisobutenyl radical and M denotes an alkaline earth metal, such as Ca, Ba or Mg. (iv) Salicylates EMI8.1 wherein A means a C8 to C22 alkyl radical and M denotes an alkaline earth metal, such as Ca, Ba or Mg. Among these metal salt detergents, calcium sulphonate, calcium phenate, calcium salicylate and magnesium salicylate are preferred. Metal naphtenates can also be used. The above metal salts may be neutral, basic or super-basic. Combinations of the metal salts may also be suitable. Preparation of greases composition The grease composition according to the present invention can be prepared by uniformly admixing and finely dispersing the three components (a), (b) and (c) in the base oil mentioned above. while the amounts of these three components compounded in the base oil above are not necessarily critical but can be variable for individual components, it is generally advantageous to use them in the following proportions per 100 weight parts (pbwl of the base oil; Component (a): 2 to 40 weight parts, preferably 5 to 30 weight parts Component (b): 0.05 to 20 weight parts, preferably 0.5 to 10 weight parts Component (c): 0.01 to 10 weight parts, preferably 0.1 to 5 weight parts Also, it is particularly preferable to use the components (a) and (b) in the following mol ratio within the above ranges of the proportions; Component(a)/Component(b) mol ratio = 0.5 to 10, especially 1 to 5. In the grease composition according to the present invention, use can be made, in addition to the three components (a), (b) and (c) above, of other ordinary lubricant-additives, such as neutral or basic metallic detergents, such as basic Ca salicylate, or ashless dispersants, rust inhibitors (e.g., paraffin oxide, amino imidazoline or barium dinonylnaphthalene-sulphonate), oxidation inhibitors (e.g. 2,6-ditertiary butyl-4-methylphenol, N-phenyl-a-naphthylamine or diphenylamine octylate) and extreme-pressure additives (e.g. zinc naphthenate, or other zinc compounds such as zinc dithiophosphates or zinc-oxide, lead naphthenate, sulphurized oils and fats, or tricresyl phosphate), in the proportions ordinarily employed. The grease composition of the present invention can e.g. be prepared in the following manner. A component (c) is first admixed and dissolved in a base oil, and the fatty acid or hydroxy fatty acid for the preparation of the lithium soap, as a component (a), is admixed and dissolved in the mixture thus obtained, at 70 to 800 C. Then, the lithium hydroxide roughly in an equivalent amount to the fatty acid or hydroxy fatty acid above is admixed in the resulting mixture at 80 to 900C to form a soap, and the mixture is further heated to 140 to 1500C under pressure for dehydration. After the dicarboxylic acid or boric acid for the formation of a component (b) is admixed in the dehydrated mixture, the resulting mixture is cooled to 80 to 100 C and further admixed with the lithium hydroxide roughly in an equivalent amount to said dicarboxylic acid or boric acid, and the final mixture is again dehydrated by heating to 140 to 1500C under pressure. The last dehydrated mixture is further heated to 195 to 215 CC, then cooled to 175 to 1930C, maintained at this temperature for about 10 to 40 min. and finally cooled to the room temperature. It is also possible to add an aqueous slurry of the reaction product of LiOH.H20 and boric acid, if this is used, to an autoclave containing lubricating oil, fatty acid and detergents, e.g. Ca salicylate and Ca naphthenate. The lithium-complex grease composition according to the present invention and thus prepared has a very high dropping point, satisfactory anti-noise properties and very long lubricating life and exhibits exceedingly high performance as a lubricating grease. Moreover, the present composition possesses a very high extreme-pressure property, in addition to the excellent properties above, due to the lithium borate contained as the component (b). Therefore, the present grease composition can be suitably used, for example, for the lubrication of the bearings fitted in electric motors as well as of the wheel bearings in automotive bearing/axle integrated structures. Furhtermore, these greases make little noise even if used in the bearings of air-conditioners and others, giving no environmental injury. In the following, the present invention is further concretely illustrated by means of examples. Example 1 2,233.5 g of a refined mineral oil (paraffinic, VI : 102, pour pt.: -150C, viscosity: 44.9 cSt at 37.80C and 6.4 cSt at 98.9 C), 300 g of the 10% solution of a hydrogenated styrene-butadiene copolymer (mean mol. wt.: about 130,000, styrene content: 59 weight %) in the mineral oil above and 270 g of 12-hydroxy stearic acid were charged into a 8 litre autoclave, and the contents were heated to 800C under stirring in 30 to 40 min to completely dissolve the 12-hydroxy stearic acid. Then, 300 g of a hot aqueous solution (95 C) containing 38.5 g of lithium hydroxide were admixed in the autoclave, the contents were stirred for about 10 min under stirring and normal pressure at about 900C and, then, slowly heated under pressure to about 1450C. At this temperature, the contents of the autoclave were further stirred for about 15 min under pressure (about 2.5 to 2.8 kg/cm2) and, subsequently, the pressure was released with the moisture being removed. After dehydration, the contents were admixed with 67.8 g of azelaic acid, the mixture was slowly cooled to about 900C under stirring, and 250 g of a hot aqueous solution (950C) containing 30.2 g of lithium hydroxide were admixed in the mixture. The resulting mixture was slowly heated to 145 to 1550C under stirring and pressure in 1 to 1.5 hrs, and, at this temperature, the autoclave was released of the pressure and removed of the moisture. After the dehydration, the contents of the autoclave were again heated to 195 to 2150C and, then, left cooling under stirring to 188 to 192QC. The contents were kept at this temperature for 20 to 30 min, then left cooling to about 1600C. At this temperature, 60 g of the oxidation inhibitor, diphenylamine octylate, were admixed in the contents, the mixture was cooled to about 80 to 850C under stirring in 30 to 60 min and treated in a homogenizer at this temperature. The properties of the grease composition thus obtained were as shown below; Consistency (unworked) : 240 (after 60 strokes) : 245 * Shell roll test (100 C x 5 hrs) (before test) : 120 (after test) : 152 (difference) : +32 ** Dropping point (OOC) : 257 Grease dust-noise test (after 120 sec) : 92 (mean of 5 measurements) * Roll stability test according to ASTM D1831, ** according to JIS K 2220, according to the method described in Japanese Patent Publication No. 2357/78. Comparison example 1 A grease composition was prepared in a similar manner to that in Example 1 except that 2,533.5 g of the refined mineral oil were used without employing the hydrogenated styrene-butadiene copolymer mentioned in Example I. The properties of the product were as follows; Consistency (unworked) : 246 (after 60 strokes) : 248 Shell roll test (1000C x 5 hrs) (before test) : 123 (after test) : 148 (difference) : +25 Dropping point (0) : 232 Grease dust-noise test (after 120 sec) : 7,534 (mean of 5 measurements) Examples 2 to 8 Grease compositions were prepared by employing the various components shown in Table 1 below in a similar manner to that in Example 1, and the properties of these compositions are collectively tabularized in Table 1. Table l EMI13.1 Composition/Example <SEP> Composition <SEP> (weight <SEP> %) <SEP> Markst <SEP> Markst <tb> <SEP> gresse <SEP> gresse <tb> Component/Property <SEP> 2 <SEP> 3 <SEP> 4 <SEP> 5 <SEP> 6 <SEP> 7 <SEP> 8 <SEP> A(8) <SEP> B(9) <tb> (a) <SEP> 12-hydroxy <SEP> atsaric <SEP> scid <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <tb> Hardened <SEP> castor <SEP> oil <tb> (b) <SEP> Azelaic <SEP> acid <SEP> 2.26 <SEP> 2.26 <SEP> 2.26 <SEP> 2.26 <SEP> 2.26 <SEP> 2.26 <SEP> 2.26 <tb> (c) <SEP> Styrene-butediene <SEP> copolymer <SEP> (hydrogenated) <SEP> (1) <tb> <SEP> styrene-isoprene <SEP> copolymer <SEP> (hydrogenated) <SEP> (2) <SEP> 1.0 <SEP> 1.0 <SEP> 1.0 <SEP> 0.67 <tb> Polymethylmethacrylate(3) <SEP> 1.0 <SEP> 0.3 <SEP> 0.22 <tb> Polyisobutylene(4) <SEP> 1.0 <tb> Ethylene-propylene <SEP> copolyzer(5) <SEP> 1.0 <tb> Lithium <SEP> hydroxide <SEP> monchydrate <SEP> 2.29 <SEP> 2.29 <SEP> 2.29 <SEP> 2.29 <SEP> 2.29 <SEP> 2.24 <SEP> 2.29 <tb> Oxidation <SEP> inhibitor <SEP> (6) <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <tb> Base <SEP> oil <SEP> (refined <SEP> mineral <SEP> oil) <SEP> (7) <SEP> 83.45 <SEP> 83.45 <SEP> 83.45 <SEP> 83.45 <SEP> 83.15 <SEP> 83.50 <SEP> 83.56 <tb> Properties <SEP> : : <tb> Consistency <SEP> (unworked) <SEP> 231 <SEP> 246 <SEP> 250 <SEP> 254 <SEP> 230 <SEP> 271 <SEP> 240 <SEP> 285 <SEP> 240 <tb> (after <SEP> 60 <SEP> atrokes) <SEP> 241 <SEP> 280 <SEP> 238 <tb> Shell <SEP> roll <SEP> test <SEP> (100 C <SEP> x <SEP> 5 <SEP> hre) <tb> (before <SEP> test) <SEP> 115 <SEP> 123 <SEP> 125 <SEP> 127 <SEP> 116 <SEP> 136 <SEP> 120 <SEP> 142 <SEP> 120 <tb> (after <SEP> test) <SEP> 139 <SEP> 140 <SEP> 127 <SEP> 168 <SEP> 140 <SEP> 163 <SEP> 141 <SEP> 153 <SEP> 135 <tb> (difference) <SEP> +24 <SEP> +17 <SEP> +32 <SEP> +41 <SEP> +24 <SEP> +27 <SEP> +21 <SEP> +11 <SEP> +15 <tb> Dropping <SEP> point <SEP> ( C) <SEP> 254 <SEP> 254 <SEP> 258 <SEP> 257 <SEP> > 262 <SEP> 261 <SEP> 244 > 275 > 275 <tb> Gresse <SEP> dust-noise <SEP> test <SEP> (after <SEP> 120 <SEP> esc) <tb> (neen <SEP> of <SEP> 5 <SEP> measurenants) <SEP> 67 <SEP> 141 <SEP> 283 <SEP> 133 <SEP> 51 <SEP> 259 <SEP> 91 <SEP> 3.399 <SEP> 1.174 <tb> Note: (13 the same as that used in Example 1 (2) mean mol. wt. : about 102,000, styrene content : 31 wt.% (3) mean mol. wt. : about 260,000 (4) mean mol. wt. : about 5,000 (5) mean mol. wt. : about 130,000, ethylene content : 30 wt. % (6) the same as that used in Example 1 (7) the same as that used in Example 1 (8) ordinary lithium-complex grease containing (9) Li 12-hydroxystearate, Li2 suberate, Li borate and Li, salicylate but no polymer. Examples 9 to 21 Grease compositions were prepared by treating the various components shown in following Tables 2A and 2B in similar manners to that in Example 1. The properties of these compositions are shown collectively in Tables 2A and 2B. Table 2A EMI15.1 Composition/Example <SEP> Composition <SEP> (weight <SEP> %) <tb> Component/Property <SEP> 9 <SEP> 10 <SEP> 11 <SEP> 12 <SEP> 13 <SEP> 14 <tb> (a) <SEP> 12-hydroxystearic <SEP> acid <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <tb> Hardened <SEP> castor <SEP> oil <SEP> 1.13 <SEP> 1.69 <SEP> 2.26 <SEP> 2.82 <tb> (b) <SEP> Azelaic <SEP> acid <tb> Adipic <SEP> acid <SEP> 1.75 <tb> Sebacic <SEP> acid <SEP> 2.42 <tb> (c) <SEP> Succinimide <SEP> type <SEP> dispersant <SEP> (A) <SEP> (l) <SEP> 1.0 <SEP> 1.0 <SEP> 1.0 <SEP> 1.0 <SEP> 1.0 <SEP> 1.0 <tb> Lithium <SEP> hydroxide <SEP> monohydrate <SEP> 1.80 <SEP> 2.03 <SEP> 2.29 <SEP> 2.53 <SEP> 2.29 <SEP> 2.29 <tb> Oxidation <SEP> inhibitor(2) <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <tb> Base <SEP> oil <SEP> (refined <SEP> mineral <SEP> oil) <SEP> (3) <SEP> 85.07 <SEP> 84.28 <SEP> 83.45 <SEP> 82.65 <SEP> 83.96 <SEP> 83.29 <tb> Properties <SEP> : <tb> Consistency <SEP> (unworked) <SEP> 288 <SEP> 256 <SEP> 237 <SEP> 252 <SEP> 310 <SEP> 252 <tb> <SEP> (after <SEP> 60 <SEP> strokes) <SEP> 249 <tb> Shell <SEP> roll <SEP> test <SEP> (100 C <SEP> x <SEP> 5 <SEP> hrs) <tb> <SEP> (before <SEP> test) <SEP> 145 <SEP> 128 <SEP> 119 <SEP> 126 <SEP> 156 <SEP> 126 <tb> <SEP> (after <SEP> test) <SEP> 174 <SEP> 156 <SEP> 143 <SEP> 167 <SEP> 183 <SEP> 160 <tb> <SEP> (difference <SEP> +29 <SEP> +28 <SEP> +24 <SEP> +41 <SEP> +27 <SEP> +34 <tb> Dropping <SEP> point <SEP> ( C) <SEP> 229 <SEP> 230 <SEP> 245 <SEP> > 262 <SEP> 237 <SEP> 245 <tb> Grease <SEP> dust-noise <SEP> test <tb> (after <SEP> 120 <SEP> sec.) <SEP> (mean <SEP> of <SEP> 5 <tb> measurements) <SEP> 268 <SEP> 270 <SEP> 238 <SEP> 293 <SEP> 285 <SEP> 290 <tb> Table 2B EMI16.1 Composition/Example <SEP> Compoisiton <SEP> (weight <SEP> %) <tb> Component/Property <SEP> 15 <SEP> 16 <SEP> 17 <SEP> 18 <SEP> 19 <SEP> 20 <SEP> 21 <tb> (a) <SEP> 12-hydroxystsaric <SEP> acid <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <tb> Hardened <SEP> castor <SEP> Oil <SEP> 9.0 <tb> (b) <SEP> Azelaic <SEP> acid <SEP> 2.26 <SEP> 2.26 <SEP> 2.26 <SEP> 2.26 <SEP> 2.26 <SEP> 2.26 <SEP> 2.26 <tb> (c) <SEP> Suncinimide <SEP> type <SEP> dispersant <SEP> (B)(4) <SEP> 1.0 <tb> <SEP> " <SEP> " <SEP> " <SEP> 1.0 <tb> <SEP> " <SEP> " <SEP> " <SEP> (C)(5) <SEP> 1.0 <SEP> 1.0 <tb> <SEP> " <SEP> " <SEP> " <SEP> (D)(6) <SEP> 1.0 <tb> Calcium <SEP> sulphonate(7) <SEP> 1.0 <tb> Msghaeium <SEP> salicylata(6) <SEP> 1.0 <tb> Calcium <SEP> salicylate(9) <tb> Lithium <SEP> hydroxide <SEP> monobydrate <SEP> 2.29 <SEP> 2.29 <SEP> 2.29 <SEP> 2.24 <SEP> 2.29 <SEP> 2.29 <SEP> 2.29 <tb> Oxydation <SEP> inhigitor(2) <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <tb> Base <SEP> Oil <SEP> (refined <SEP> mineral <SEP> Oil)(3) <SEP> 83.45 <SEP> 83.45 <SEP> 83.45 <SEP> 83.50 <SEP> 83.45 <SEP> 83.45 <SEP> 83.45 <tb> Properties <tb> Coneistency <SEP> (unworked) <SEP> 242 <SEP> 260 <SEP> 262 <SEP> 248 <SEP> 230 <SEP> 240 <SEP> 254 <tb> Shell <SEP> roll <SEP> test <SEP> (100 C <SEP> x <SEP> 5 <SEP> hre) <tb> <SEP> (before <SEP> test) <SEP> 121 <SEP> 130 <SEP> 131 <SEP> 124 <SEP> 115 <SEP> 120 <SEP> 127 <tb> <SEP> (after <SEP> test) <SEP> 161 <SEP> 166 <SEP> 177 <SEP> 148 <SEP> 140 <SEP> 141 <SEP> 150 <tb> <SEP> (diffenence) <SEP> +40 <SEP> +36 <SEP> +46 <SEP> +24 <SEP> +25 <SEP> +21 <SEP> +23 <tb> Dropping <SEP> point <SEP> ( C) <SEP> 253 <SEP> 254 <SEP> 249 <SEP> 248 <SEP> 238 <SEP> 257 <SEP> 249 <tb> Grease <SEP> dust-noise <SEP> test <SEP> (after <SEP> 120 <SEP> sec) <SEP> 165 <SEP> 265 <SEP> 169 <SEP> 244 <SEP> 166 <SEP> 229 <SEP> 291 <tb> Note: EMI17.1 A1 = polyisobutenyl radical of C52 to 5 ó Mean mol. wt. = 2302 (as containing boron) 110 weight parts of the compound above dissolved in 100 weight parts of the refined mineral oil. (2) the same as that used in Example 1. (3) the same as that used in Example 1. (4) EMI17.2 AI = polyisobutenyl radical of C52 to C76, Mean mol. wt. = 2170 110 weight parts of the compound above dissolved in 100 weight parts of the refined mineral oil. EMI18.1 A = polyisobutenyl radical of C52 to C76, Mean mol. wt. = 1172 160 weight parts of the compound above dissolved in 100 weight parts of the refined mineral oil. EMI18.2 AI = polyisobutenyl radical of C52 to C76, Mean mol. wt. = 1304 140 weight parts of the above compound dissolved in 100 weight parts of the refined mineral oil. (7) Calcium dinonylnaphthalene-sulphonate EMI18.3 r weight parts or the compound above dissolved in iuu weight parts of the refined mineral oil. (8) Magnesium alkyl-salicylate EMI19.1 R = identical or different alkyl radical of C10 to C16 30 weight parts of the compound above dissolved in 100 weight parts of the refined mineral oil. (9) Calcium alkyl-salicylate EMI19.2 R = identical or different alkyl radical of C10 to C16 35 weight parts of the compound above dissolved in 100 weight parts of the refined mineral oil. Examples 22 to 25 and Comparison Examples 2 and 3 Grease compositions were prepared by treating the various components shown in following Table 3 in similar manners to that in Example 1. The properties of these compositions are collectively tabularized in Table 3. Table 3 EMI20.1 Composition/Example <SEP> Composition <SEP> (seight <SEP> %) <tb> Component/Property <SEP> 22 <SEP> 23 <SEP> 24 <SEP> 25 <SEP> Compar. <SEP> 2 <SEP> Compar. <SEP> 3 <tb> (a) <SEP> 12-hydroxy <SEP> stearic <SEP> acid <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <tb> (b) <SEP> Boric <SEP> acid <SEP> 1.48 <SEP> 1.48 <SEP> 1.48 <SEP> 0.45 <SEP> 0.45 <SEP> 1.48 <tb> (c) <SEP> Succinimide <SEP> type <SEP> dispersant <SEP> (A)(1) <SEP> 1.0 <SEP> 1.0 <SEP> 0.5 <tb> Styrene-isoprene <SEP> copolymer <SEP> (hydrogenated)(2) <SEP> 1.0 <SEP> 0.5 <tb> Lithium <SEP> hydroxide <SEP> monohydrate <SEP> 2.30 <SEP> 2.30 <SEP> 2.30 <SEP> 1.60 <SEP> 1.60 <SEP> 2.30 <tb> Oxidation <SEP> inhibitor(3) <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <tb> Base <SEP> oil <SEP> (refined <SEP> mineral <SEP> oil)(4) <SEP> 84.22 <SEP> 84.22 <SEP> 84.22 <SEP> 83.95 <SEP> 66.95 <SEP> 85.22 <tb> Properties <SEP> : <tb> Consiatency <SEP> (unworked) <SEP> 238 <SEP> 246 <SEP> 237 <SEP> 223 <SEP> 269 <SEP> 231 <tb> (sfter <SEP> 60 <SEP> strokes) <SEP> 263 <tb> Shell <SEP> roll <SEP> test <SEP> (100 C <SEP> x <SEP> 5 <SEP> hrs) <tb> <SEP> (before <SEP> test) <SEP> 119 <SEP> 123 <SEP> 118 <SEP> 111 <tb> <SEP> (aftar <SEP> test) <SEP> 142 <SEP> 148 <SEP> 135 <SEP> 146 <tb> <SEP> (difference) <SEP> +23 <SEP> +25 <SEP> +17 <SEP> +35 <tb> Dropping <SEP> point <SEP> ( C) <SEP> > 270 <SEP> > 265 <SEP> 286 <SEP> 272 <SEP> 221 <SEP> 251 <tb> Grease <SEP> dust-noise <SEP> test <tb> (after <SEP> 120 <SEP> sec, <SEP> mean <SEP> of <SEP> 5 <tb> mesaurements) <SEP> 147 <SEP> 160 <SEP> 191 <SEP> 128 <SEP> 1,178 <SEP> 2,956 <tb> Note: (1) the sameas that used in Example 9 (2) Mean mol. wt. : about 102,000 Styrene content: 31 wt % (3) the same as that used in Example I (4) the same as that used in Example 1 Example 26 2,521.2 g of a refined mineral oil (paraffinic, VI: 102, pour point : -150C, kin. viscosity : 44.9 cSt at 37.80C, 6.4 cSt at 98.9 C), 30 g of a succinimide (A) (ref. Note 1) and 270 g of 12-hydroxy stearic acid were introduced into a 5 liter autoclave and the contents were heated to 800C under stirring in 30 to 40 min to completely dissolve the hydroxystearic acid. (Note 1) Succinimide (A) EMI21.1 A1 : C52 to C76 polyisobutenyl radical, mean molecular weight : 2,302 (as containing boron), 110 wt. parts of the compound above dissolved in 100 wt. parts of the base oil. Subsequently, 300 g of a hot aqueous solution (95 C) containing 38.5 g of lithium hydroxide were admixed in the autoclave contents, which were then kept at 900C under stirring for 5 to 15 min. After the contents were cooled to 750C, 300 g of a hot aqueous solution (930C) containing 49.8 g of salicylic acid were admixed in the contents and dissolved by stirring for 10 to 15 min. Then, 250 g of a hot aqueous solution (950C) containing 31.0 of lithium hydroxide were admixed in the resulting mixture, which was then gradually heated under stirring and pressure. When this mixture arrived at 145 to 1500C after I to 1.5 hrs, the autoclave was released of the pressure and the contents were dehydrated at this temperature in 15 to 25 min. After the dehydration, the contents of the autoclave were further heated to 195 to 2050C, then cooled to 188 to 1920C under stirring and, after being kept at this temperature for 20 to 30 min, further cooled to about 1600C. At this temperature, 60 g of an oxidation inhibitor were admixed in the contents, the mixture thus obtained was cooled by stirring to about 80 to 850C in 30 to 60 min and then treated in a homogenizer at this temperature. The properties of the grease composition thus prepared were as follows; *1 Consistency (unworked) : 239 IT (after 60 strokes) : 236 Shell roll test 2 (100 C x 5 hrs) (before test) : 119 (after test) : 149 (difference) : +30 Dropping point *1 ( C) : 280 Oil separation *1 (100 C x 24 hrs) : 2.2 % Water resistance (38 C x 1 hr) : 2.0% Copper-plate corrosion *1 (100 C x 24 hrs) : pass *3 Grease dust-noise test (after 120 sec) : 68 (mean of 5 measurements) Functional life : 2540 hrs Note *1 : according to JIS K 2220, *2 : roll stability test according to ASTM D1831, *3 : according to the method described in Japanese Patent Publication No. 2357/78, *4 : according to ASTM D1741 Comparison Example 4 A grease composition was prepared in a similar manner to that in Example 1 except that 2,531.2 g of the refined mineral oil were employed without the succinimide(A) being admixed. The properties of the resulting composition were as follows; Consistency (unworked) : 278 (after 60 strokes) : 266 Shell roll test (1O00C x 5 hrs) (before test) : 139 (after test) : 173 (difference) : +34 Dropping point (OC) : 195 Grease dust-noise test (after 120 sec): 4,114 (mean of 5 measurements) Functional life : 1,240 hrs Examples 27 to 33, Comparison Examples 5 and 6 Seven grease compositions were prepared by treating the various components shown in Table 4 below in similar ways to that in Example 26 and the properties thereof are collectively tabularized in Table 4. Also, the properties of a market grease comprising the lithium soap of 12-hydroxystearic acid are shown as * Comparison Example 5 in the table as well. In addition, Comparison Example 6 in the Table is a grease prepared in a similar manner to that in Example 26 but by employing in a similar manner to that in Example 26 but by employing an increase amount of the refined mineral oil without the components (b) and (c) being admixed. Table 4 EMI24.1 Composition/Example <SEP> Composition <SEP> (weight <SEP> %) <tb> Componont/Proparty <SEP> 27 <SEP> 28 <SEP> 29 <SEP> 30 <SEP> 31 <SEP> 32 <SEP> 33 <SEP> C-5* <SEP> C-6 <tb> (a) <SEP> 12-hydroxy <SEP> stearic <SEP> acid <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <SEP> 9.0 <tb> (b) <SEP> Salicylic <SEP> acid <SEP> 1.66 <SEP> 1.66 <SEP> 1.66 <SEP> 1.66 <SEP> 1.66 <SEP> 1.66 <SEP> 1.66 <tb> (c) <SEP> Succinimide <SEP> (B),(1) <SEP> 1.0 <SEP> Market <tb> <SEP> Succinimide <SEP> (C),(2) <SEP> 1.0 <SEP> greass <tb> <SEP> Succinimide <SEP> (D),(3) <SEP> 1.0 <tb> <SEP> Calcium <SEP> sulphonate, <SEP> (4) <SEP> 1.0 <SEP> 0.5 <tb> <SEP> Magnesium <SEP> salicylata, <SEP> (5) <SEP> 1.0 <tb> <SEP> Calcium <SEP> salicylats, <SEP> (6) <SEP> 1.0 <tb> Lithium <SEP> hydroxyde <SEP> monohydrate <SEP> 2.30 <SEP> 2.30 <SEP> 2.30 <SEP> 2.30 <SEP> 2.30 <SEP> 2.30 <SEP> 2.30 <SEP> 1.29 <tb> Oxidation <SEP> inhibitor, <SEP> (7) <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <SEP> 2.0 <tb> Base <SEP> oil <SEP> (refined <SEP> mineral <SEP> o'l), <SEP> (8)84.04 <SEP> 84.04 <SEP> 84.04 <SEP> 84.04 <SEP> 84.04 <SEP> 84.04 <SEP> 84.04 <SEP> 67.71 <tb> Properties <SEP> : : <tb> Consistency <SEP> (unworked) <SEP> 221 <SEP> 218 <SEP> 255 <SEP> 242 <SEP> 229 <SEP> 258 <SEP> 241 <SEP> 272 <SEP> 234 <tb> <SEP> " <SEP> (after <SEP> 60 <SEP> atrokes) <SEP> 222 <SEP> 214 <SEP> 248 <SEP> 240 <SEP> 226 <SEP> 251 <SEP> 239 <SEP> 273 <SEP> 232 <tb> Shell <SEP> roll <SEP> test, <SEP> (before <SEP> test) <SEP> 110 <SEP> 108 <SEP> 128 <SEP> 121 <SEP> 114 <SEP> 130 <SEP> 121 <SEP> 137 <SEP> 117 <tb> (100 C <SEP> x <SEP> 5 <SEP> hrs) <SEP> (after <SEP> test) <SEP> 138 <SEP> 129 <SEP> 157 <SEP> 154 <SEP> 151 <SEP> 163 <SEP> 160 <SEP> 168 <SEP> 165 <tb> <SEP> (difference) <SEP> +28 <SEP> +21 <SEP> +29 <SEP> +33 <SEP> +37 <SEP> +33 <SEP> +39 <SEP> +31 <SEP> 48 <tb> Dropping <SEP> point <SEP> ( C) <SEP> > 280 <SEP> > 280 <SEP> > 280 <SEP> > 280 <SEP> > 280 <SEP> > 280 <SEP> > 280 <SEP> 180 <SEP> 200 <tb> Gresse <SEP> dust-noise <SEP> test <tb> (after <SEP> 120 <SEP> esc) <SEP> 48 <SEP> 102 <SEP> 80 <SEP> 66 <SEP> 121 <SEP> 65 <SEP> 93 <SEP> 50 <SEP> 140 <tb> Functional <SEP> life <SEP> (hr) <SEP> 3020 <SEP> 1860 <SEP> 2540 <SEP> 2660 <SEP> 1780 <SEP> 2480 <SEP> 2800 <SEP> 500 <SEP> 480 <tb> Note for Table 4: EMI25.1 A1 : C52 to C76 polyisobutenyl radical, Mean molecular weight : 2,170 110 weight parts of the above compound dissolved in 100 weight parts of a refined mineral oil. EMI25.2 A1 : C52 to C76 polyisobutenyl radical, Mean molecular weight: 1,172 160 weight parts of the compound above dissolved in 100 weight parts of a refined mineral oil. EMI25.3 A : C52 to C76 polyisobutenyl radical, Mean molecular weight : 1304 140 weight parts of the compound above dissolved in 100 weight parts of a refined mineral oil. (4) Calcium dinonylnaphthaiene-sulphate EMI26.1 39 weight parts of the compound above dissolved in I00 weight parts of a refined mineral oil. (5) Magnesium alkyl-salicylate EMI26.2 R: C10 to C16 alkyl radical 30 weight parts of the compound above dissolved in 100 weight parts of a refined mineral oil. (6) Calcium alkyl-salicylate EMI26.3 R : C10 to C16 alkyl radical 30 weight parts of the compound dissolved in 100 weight parts of a refined mineral oil. (7) The same as that used in Example 26 (8) The same as that used in Example 26

Claims: CLAIMS 1. High dropping-point lithium-complex grease composition having improved anti-noise properties, comprising a lubricating oil and the following components: (a) at least one lithium soap selected from the group consisting of the lithium salts of Clo to C34 fatty acids and C12 to C24 hydroxy fatty acids, (b) at least one lithium salt selected from the group consisting of the dilithium salts of C4 to C12 aliphatic c dicarboxylic acids, the lithium salts of boric acids,and the lithium salts of aromatic hydroxy carboxylic acids, and (c) a high-molecular viscosity-index improver, and/or succinimide-type dispersant and/or metal salt detergent. 2. Composition as claimed in claim 1, wherein component (b) is selected from the group consisting of the dilithium salt of adipic acid, sebacic acid or azelaic acid, the mono lithium salt of ortho boric acid and lithium salicylate. 3. Composition as claimed in claim 1 or 2, wherein component (c) is selected from the group consisting of methacrylate polymers, hydrogenated styrene-butadiene copolymers, hydrogenated styrene-isoprene copolymers and ethylene-propylene copolymers. 4. Composition as claimed in claim 1 or 2, wherein component (c) is selected from the group consisting of calcium sulphonate, calcium salicylate and magnesium salicylate. 5. Composition as claimed in any one of claims 1-4, wherein the proportions per 100 pbw of base oil are: component (a) : 2-40 pbw component (b) : 0.05-20 pbw component (c) : 0.01-10 pbw 6. Composition as claimed in any one of claims 1-5, wherein the mol ratio component (a)/component (b) = 0.5 to 10.

Inventors: OKAMOTO, TOSHIKO, TAJIRI, HIROSHI, TANAKA, NORIMITSU
Applicants: SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ B.V.
Application year: 1983
Main classification: C10M123
IPC codes: C10M169