Lubricating grease composition and its use

Abstract

A lubricating grease composition containing one or more base oils, a thickening agent, and one or more solid lubricants. wherein the base oil is a synthetic hydrocarbon oil with a kinematic viscosity of 600 to 2000 mm² 2 / s at 40°C is, the thickening agent is one or more barium complex soaps, as well as The solid lubricant consists of inorganic fine particles with a Mohs hardness of 3 to 6 and an average grain size of 20 to 40 µm. wherein the solid lubricant content is 10 to 60 wt.% based on the total weight of the lubricating grease composition, and wherein the content of one or more barium complex soaps is 10 - 30 wt.%, based on the total weight of the lubricating grease composition.

Description

[Technical field]

[0001] The present invention relates to a lubricating grease composition having a high static coefficient of friction and excellent durability, and its use for a sliding section between resin parts or between a resin part and a metal part, for a clutch and a window regulator motor with the clutch. [State of the art]

[0002] Until now, greases have been used as lubricants for gears and sliding parts. In recent years, resin components have been increasingly used for gears and sliding parts in automotive components, electrical household appliances, electronic information devices, office machines, etc., for the purpose of weight reduction and cost reduction.

[0003] In recent years, it has also become increasingly important for grease used in sliding sections between resin parts or between a resin part and a metal part in a reduction gear section, a clutch section, or similar component in the reduction gear of a motor vehicle or office machine. This grease must have a high static coefficient of friction to prevent slippage when stationary. Furthermore, such grease must have high durability (i.e., the static coefficient of friction must not change over time, and the sliding section must not emit noise).

[0004] For example, JP patent specification JP 5450935 B2 discloses a lubricating grease composition with a high static coefficient of friction, which is used for a sliding section between resin parts or between a resin part and a metal part.

[0005] In JP patent application JP 2012-082952 A, a coupling for preventing reverse rotation is further disclosed. This coupling is attached to a motor serving as the drive source for an electric window lifter. Within an annular collar, the coupling comprises a drive-side rotating element that rotates integrally with the drive shaft, an output-side rotating element that rotates integrally with the worm shaft, and a rolling element. The output-side rotating element has a control surface opposite the inner circumferential surface of the collar, and the rolling element is arranged between this control surface and the inner circumferential surface of the collar.In a motor with such a coupling, the rolling element, the output rotating body, and the worm shaft rotate integrally when the input rotating body is driven by the rotary drive of the drive shaft. Based on the rotation of the drive shaft, a vehicle window is opened and closed. Conversely, when the drive shaft (drive rotating body) is not driven, the rolling element is wedged between the control surface of the output rotating body and the inner circumferential surface of the collar, thus preventing rotation of the output rotating body. This prevents the vehicle window from being opened and closed by any external force other than the motor's drive force.

[0006] Grease is applied to the inner circumferential surface of the collar. When the driven-side rotating body rotates while the rotating shaft (drive-side rotating body) is not being driven, the grease enters between the collar and the rolling element. This increases the frictional force acting between the collar and the rolling element, preventing the rolling element from being jammed by the control surface of the driven-side rotating body and the inner circumferential surface of the collar, thus preventing the rolling element from rotating together with the driven-side rotating body.

[0007] In recent years, the properties required for a lubricating grease composition have become stricter, so that a lubricating grease composition with a higher static coefficient of friction and better durability than before has been desired.

[0008] JP 2014-194006 A discloses a thermally conductive grease composition with inorganic fine particles of zinc oxide, which form a filler. The concentration of this filler is increased to achieve improved thermal conductivity, which is desirable for use in semiconductor chips, CPUs, or LEDs. The grease composition comprises a synthetic hydrocarbon oil, the precursor of which is a lubricating oil distillate; an inorganic powder filler of zinc oxide with an average particle size of 3–50 µm and a Mohs hardness of 4–5; and a barium complex soap as a thickener. The concentration of the inorganic powder filler is 70 to 98% by weight, with the thermal conductivity being better the higher the concentration, preferably 75 to 97% by weight. If the concentration is below 70% by weight, the thermal conductivity may be low, or the oil may be easily released.The fat composition has a kinematic viscosity of 10 mm. 2 / s up to 1,200 mm 2 / s at 40°C.

[0009] DE 11 2012 005 505 T5 discloses a thermally conductive resin composition, EP 3 109 300 A1 discloses a lubricating grease composition for use in high friction environments, especially in couplings, and EP 2 133 407 A1 discloses a fire-resistant lubricating grease composition. [Disclosure of the invention]

[0010] The present invention is therefore based on the above facts and its purpose is to provide a lubricating grease composition with a high static coefficient of friction and excellent durability.

[0011] The essential features of the present invention are as follows: [1] A lubricating grease composition comprising one or more base oils, one or more thickening agents and one or more solid lubricants, wherein the base oil is a synthetic hydrocarbon oil having a kinematic viscosity of 600 to 2000 mm 2 / s at 40°C is, the thickening agent is one or more barium complex soaps, as well as The solid lubricant consists of inorganic fine particles with a Mohs hardness of 3 to 6 and an average grain size of 20 to 40 µm. wherein the solid lubricant content is 10 to 60 wt.%, based on the total weight of the The lubricating grease composition consists of one or more barium complex soaps, and the content of one or more barium complex soaps is 10 to 30 wt.%, based on the total weight of the lubricating grease composition. The content of the thickening agent, i.e., one or more barium complex soaps, is 10 to 30 wt.%, based on the total weight of the lubricating grease composition. [2] Use of the grease composition according to point [1] for a sliding section between resin parts or between a resin part and a metal part. [3] The use of the grease composition according to point [2], wherein the sliding section is a sliding section of a coupling. [4] Use of the lubricating grease composition according to point [1] in a window regulator motor with a clutch

[0012] The grease composition according to the present invention exhibits a high static coefficient of friction and excellent durability. The grease composition according to the present invention is particularly suitable for use in a sliding section between resin parts or between a resin part and a metal part. [Emphasis of the invention]

[0013] A lubricating grease composition according to the present invention comprises one or more base oils, one or more thickening agents and one or more solid lubricants.

[0014] The base oil used in the present invention is not particularly restricted, as long as it is a synthetic hydrocarbon oil, and examples include poly-α-olefin, ethylene-α-olefin co-oligomer, ethylene-α-olefin copolymer, polybutene, alkylbenzene, alkylnaphthalene, etc. Poly-α-olefin is preferred among these. The base oils can be used individually or in combination.

[0015] The kinematic viscosity of the base oil at 40°C is 600 to 2000 mm². 2 / s. If the kinematic viscosity of the base oil at 40°C is less than 600 mm² 2 If the viscosity is / s, the durability of the grease composition is reduced. If, on the other hand, the kinematic viscosity of the base oil at 40°C is 2000 mm², the durability of the grease composition is reduced. 2If the coefficient of friction exceeds a certain value ( / s), the static coefficient of friction decreases. The kinematic viscosity of the base oil at 40°C can be measured according to JIS K 2283. The kinematic viscosity of the base oil at 40°C is preferably 800 to 1500 mm². 2 / s. By keeping the kinematic viscosity of the base oil in these ranges at 40°C, a grease composition with a high static coefficient of friction and excellent durability can be obtained.

[0016] The thickening agent used in the present invention is a barium complex soap. Either one type of barium complex soap, or two or more types, can be used as the thickening agent. By using a barium complex soap as the thickening agent, a lubricating grease composition with a high static coefficient of friction can be obtained. Examples of barium complex soaps include a salt of an aliphatic dicarboxylic acid and a carboxylic acid amide. Examples of aliphatic dicarboxylic acids include sebacic acid, azelaic acid, etc. The content of the thickening agent, i.e., the one or more barium complex soaps, is 10 to 30 wt.%, based on the total weight of the lubricating grease composition. By maintaining a thickening agent content within this range, a lubricating grease composition with a high static coefficient of friction can be obtained.

[0017] The solid lubricant used in the invention consists of inorganic fine particles with a Mohs hardness of 3 to 6 and an average particle size of 20 to 40 µm. Mohs hardness is a measure of the hardness of minerals, numbered from 1 to 10, with diamonds achieving the highest value of 10. The measurement method involves rubbing a sample object with a reference mineral to determine whether or not it is scratched, and the hardness is then measured. The average particle size of the inorganic fine particles is also measured using a laser diffraction particle size distribution (PSP) device. When the Mohs hardness of the inorganic fine particles is less than 3, the static coefficient of friction of the grease composition decreases, whereas the durability of the grease composition deteriorates when the Mohs hardness exceeds 6.As described above, inorganic fine particles with a Mohs hardness of 3 to 6 and an average particle size of 20 to 40 µm are suitable. If the average particle size of the inorganic fine particles is less than 10 µm, the static coefficient of friction of the grease composition decreases, and if the average particle size exceeds 40 µm, the durability of the grease composition deteriorates.

[0018] The average particle size of the inorganic fine particles is therefore 20 to 40 µm. Because the average particle size of the inorganic fine particles lies within this range, the lubricating grease composition can exhibit a higher static coefficient of friction. Examples of inorganic fine particles include calcium carbonate, fluorite, magnesium oxide, etc.

[0019] According to the invention, the solid lubricant content is 10 to 60 wt.% and preferably more, preferably 30 to 50 wt.%, based on the total weight of the grease composition. If the solid lubricant content is 10 wt.% or more based on the total weight of the grease composition, the static coefficient of friction of the grease composition increases, thus effectively preventing slippage at standstill when the grease composition is used for a sliding section between resin parts or between a resin part and a metal part. Furthermore, if the solid lubricant content is 60 wt.% or less based on the total weight of the grease composition, the grease composition does not harden, thus preventing a reduction in torque performance at low temperatures.

[0020] In the grease composition according to the present invention, the work penetration is preferably 240 to 320. If the work penetration is 240 or higher, the grease composition exhibits excellent torque characteristics at low temperatures and can slide smoothly in low-temperature environments. Furthermore, if the work penetration is 320 or lower, the oil separation properties at high temperatures are improved. The work penetration can be measured according to the method specified in JIS K 2220 7.

[0021] The lubricating grease composition according to the present invention can contain additives in such quantities that they do not affect the effectiveness of the additives. For example, known antioxidants, high-pressure agents, rust inhibitors, corrosion inhibitors, viscosity index improvers, etc., can be selected and included as appropriate.

[0022] Examples of antioxidants include: phenol-based antioxidants such as 2,6-di-tert-butyl-4-methylphenol and 4,4'-methylenebis(2,6-di-tert-butylphenol), etc.; amine-based antioxidants such as alkyldiphenylamine, triphenylamine, phenyl-α-naphthylamine, phenothiazine, alkylated phenyl-α-naphthylamine, alkylated phenothiazine, etc.; and also phosphate-based and sulfur-based antioxidants, etc.

[0023] Examples of high-pressure agents include: phosphorus-based compounds such as phosphoric acid esters, phosphorous acid esters and phosphoric acid esteramine salts, etc.; sulfur compounds such as sulfides and disulfides, etc.; sulfur-based metal salts such as dialkyldithiophosphoric acid metal salts and dialkyldithiocarbamic acid metal salts, etc.; and chlorine compounds such as chlorinated paraffins, chlorinated diphenyl, etc.

[0024] Examples of rust inhibitors include fatty acids, fatty acid amines, metal sulfonates, alkylsulfonic acid metal salts, alkylsulfonic acid amine salts, oxidized paraffin, polyoxyethylene alkyl ethers, etc.

[0025] Examples of corrosion inhibitors include benzotriazole, benzimidazole, thiadiazole, sodium sebacate, etc.

[0026] Examples of viscosity index improvers include polymethacrylate, ethylene-propylene copolymer, polyisobutylene, polyalkylstyrene, hydrogenated styrene-isoprene copolymer, etc.

[0027] Due to its claimed characteristics, the lubricating grease composition according to the present invention exhibits a high static coefficient of friction and excellent durability. The lubricating grease composition according to the present invention is particularly suitable for use in a sliding section between resin parts or between a resin part and a metal part. The sliding section is preferably a sliding section of a coupling. Although the devices on which the coupling is mounted are not particularly restricted, a window regulator motor can be cited as an example. For instance, the coupling mounted in the window regulator motor could be...A coupling to prevent reverse rotation is provided, which connects a rotary shaft for generating a rotary drive force of the window lift motor to a worm shaft of a reduction mechanism for reducing the rotary drive force transmitted by the rotary shaft and prevents reverse rotation of the motor due to an external force. [Examples of implementation]

[0028] Preferred embodiments of the present invention are explained below based on exemplary embodiments, wherein exemplary embodiment 6 is not according to the invention, and comparative examples; however, the present invention is not limited to these exemplary embodiments. (1) Method for producing a lubricating grease composition

[0029] A lubricating grease composition (test oil) was prepared such that the following components each had the contents (wt%) shown in Tables 1 and 2. The types of the respective components are specified below. <Grundöl>

[0030] Base oil A (synthetic hydrocarbon oil), kinematic viscosity at 40°C 600 mm 2 / s: Mixed base oil from product name “DURASYN® 166” (manufactured by Ineos Oligomers Japan, kinematic viscosity at 40°C 30 mm) 2 / s) and product name “LUCANT® HC-2000” (manufactured by Mitsui Chemicals, kinematic viscosity at 40°C 37500 mm²) 2 / s) (DURASYN® 166: LUCANT® HC-2000 = 60% by weight: 40% by weight)

[0031] Base oil B (synthetic hydrocarbon oil), kinematic viscosity at 40°C 1000 mm 2 / s: Mixed base oil from product name “DURASYN® 166” (manufactured by Ineos Oligomers Japan, kinematic viscosity at 40°C 30 mm)2 / s) and product name “LUCANT® HC-2000” (manufactured by Mitsui Chemicals, kinematic viscosity at 40°C 37500 mm²) 2 / s) (DURASYN® 166: LUCANT® HC-2000 = 55% by weight: 45% by weight)

[0032] Base oil C (synthetic hydrocarbon oil), kinematic viscosity at 40°C 2000 mm 2 / s: Mixed base oil from product name “DURASYN® 166” (manufactured by Ineos Oligomers Japan, kinematic viscosity at 40°C 30 mm) 2 / s) and product name “LUCANT® HC-2000” (manufactured by Mitsui Chemicals, kinematic viscosity at 40°C 37500 mm²) 2 / s) (DURASYN® 166: LUCANT® HC-2000 = 45% by weight: 55% by weight)

[0033] Base oil D (synthetic hydrocarbon oil): “DURASYN® 166” (manufactured by Ineos Oligomers Japan, kinematic viscosity at 40°C 30 mm) 2 / s)

[0034] Base oil E (synthetic hydrocarbon oil), kinematic viscosity at 40°C 3000 mm 2 / s: Mixed base oil from product name “DURASYN® 166” (manufactured by Ineos Oligomers Japan, kinematic viscosity at 40°C 30 mm) 2 / s) and product name “LUCANT® HC-2000” (manufactured by Mitsui Chemicals, kinematic viscosity at 40°C 37500 mm²) 2 / s) (DURASYN® 166: LUCANT® HC-2000 = 40% by weight: 60% by weight) <verdickungsmittel>

[0035] Thickener A: Barium complex soap; Thickener B: Lithium soap; Product name “Li-OHST” (manufactured by Katsuta Kako Co., Ltd.) <festschmierstoff> Solid lubricant A: Calcium carbonate, product name “SFT-2000” (manufactured by Sankyo-Seifun, Mohs hardness 3 to 4, average grain size 30 µm) Solid lubricant B: Calcium carbonate, product name “A” (manufactured by Sankyo-Seifun, Mohs hardness 3 to 4, average grain size 10 µm) Solid lubricant C: Magnesium oxide, product name “Pyrokisuma 3320” (manufactured by Kyowa Chemical Industry Co., Ltd., Mohs hardness 4 to 6, average particle size 20 µm) Solid lubricant D: Silica, product name “SP-4200” (manufactured by San-Ei Silica Co., Ltd., Mohs hardness 7, average particle size 22 µm) Solid lubricant E: Mica, product name “MK-300” (manufactured by Katakura & Co-op Agri Co., Mohs hardness 2.8, average particle size 15 µm) Solid lubricant F: Calcium carbonate, product name “#3500” (manufactured by Sankyo-Seifun, Mohs hardness 3 to 4, average grain size 1 µm) Solid lubricant G: Calcium carbonate, product name “G-120” (manufactured by Sankyo-Seifun, Mohs hardness 3 to 4, average grain size 50 µm) Solid lubricant H: Polytetrafluoroethylene (PTFE), product name “Dyneon TF 9207 Z” (manufactured by 3M Japan Ltd.) Solid lubricant I: Melamine cyanurate (MCA), product name “MC-6000” (manufactured by Nissan Chemical Industries, Ltd.) <antioxidationsmittel>

[0036] Phenylnaphthylamine: Product name “VANLUBE® 81” (manufactured by Sanyo Chemical Industries, Ltd.) <rostinhibitor>

[0037] Neutral calcium sulfonate: Product name “NA-SUL® CA-1089” (manufactured by King)

[0038] The lubricating grease composition with thickener A was prepared as follows.

[0039] First, a base oil, sebacic acid, and carboxylic acid monostearylamide were mixed in a stirred tank and stirred while heated to approximately 80 to 200°C. Barium hydroxide was then added, and a saponification reaction was carried out to produce a barium complex soap. The respective components of the thickening agent were mixed in a ratio of 27.5 wt% sebacic acid, 41.5 wt% carboxylic acid monostearylamide, and 31 wt% barium hydroxide, based on the total amount of thickening agent. The barium complex soap was then cooled, various additives were added to the resulting gel-like substance, and the mixture was stirred. Finally, the lubricating grease composition was produced by passing it through a roller mill or a high-pressure homogenizer.

[0040] The lubricating grease composition with thickener B was prepared as follows.

[0041] First, the base oil, 12-hydroxystearic acid, and lithium hydroxide were mixed in a stirred tank, stirred while heated to approximately 80 to 130°C, and a saponification reaction was carried out to produce a lithium soap. The respective components of the thickening agent were mixed in a ratio of 88% by mass of 12-hydroxystearic acid and 12% by mass of lithium hydroxide, based on the total amount of thickening agent. The lithium soap was then cooled, various additives were added to the resulting gel-like substance, and the mixture was stirred. Finally, the lubricating grease composition was produced by passing it through a roller mill or a high-pressure homogenizer. [Table 1] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Base oil A 33.5 30 Base oil B 33.5 64.5 Base oil C 33.5 64.5 Base oil D Base oil E Thickener A 15 15 15 24 24 13.5 Thickener B Solid lubricant A 50 10 Solid lubricant B 55 Solid lubricant C 50 50 10 Solid lubricant D Solid lubricant E Solid lubricant F Solid lubricant G Solid lubricant H Solid lubricant I Antioxidants 1 1 1 1 1 1 Rust inhibitor 0.5 0.5 0.5 0.5 0.5 0.5 Total quantity 100 100 100 100 100 100 Base oil viscosity (40°C) 600 1000 2000 2000 1000 600 [Table 2] Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 Comparative example 5 Comparative example 6 Comparative example 7 Comparative example 8 Comparative example 9 Base oil A 50.5 33.5 Base oil B 64.5 33.5 43.5 53.5 Base oil C Base oil D 28.5 79.5 Base oil E 33.5 Thickener A 20 15 24 15 18 15 19 Thickener B 5 8 Solid lubricant A 50 50 50 Solid lubricant B Solid lubricant C Solid lubricant D 10 Solid lubricant E 50 Solid lubricant F 30 Solid lubricant G 50 Solid lubricant H 10 1 solid lubricant 16 10 Antioxidants 1 1 1 1 1 1 1 1 1 Rust inhibitor 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Total quantity 100 100 100 100 100 100 100 100 100 Base oil viscosity (40°C) 30 3000 1000 1000 1000 600 600 1000 30 (2) Evaluation method(2-1) Static coefficient of friction

[0042] Using a reciprocating motion testing machine, a test oil was applied to a lower specimen, and an upper specimen was pressed down from above to move back and forth. The static coefficient of friction was measured from the frictional force occurring between the upper and lower specimens during this movement. The test conditions are shown below: Top sample: Polyimide (PI) sphere with a diameter of 10 mm Lower test piece: Chromium-molybdenum steel (SCM) plate Test load: 10 kgf Application quantity of test oil: 0.05 g Sliding speed: 10 mm / sec Test temperature: normal temperature; sliding distance: 10 mm

[0043] Evaluation criterion: A case in which the static coefficient of friction during the first sliding is greater than 0.15 was evaluated as “o”, and a case in which the static coefficient of friction is equal to or less than 0.15 was evaluated as “×”. (2-2) Durability

[0044] It was judged that the grease composition is distinguished in terms of durability if (a) the static coefficient of friction does not change over time, and (b) the sliding section does not produce any noise. More specifically, a test was carried out under the same conditions as in section (2-1) "Static Coefficient of Friction" above, and if the static coefficient of friction at the hundredth slide is greater than 0.15, it was judged as (a), meaning that the static coefficient of friction does not change over time, and if the dynamic coefficient of friction at the hundredth slide is less than 0.15, it was judged as (b), meaning that the sliding section does not produce any noise. If, then, the static coefficient of friction at the hundredth slide is greater than 0.15 and the dynamic coefficient of friction is less than 0.15, this was judged as "o".Furthermore, if the static coefficient of friction on the hundredth slide is 0.15 or less, if the dynamic coefficient of friction is 0.15 or greater, or if the static coefficient of friction is 0.15 or less and the dynamic coefficient of friction is 0.15 or greater, this was judged as “×”.

[0045] The evaluation results are shown in Tables 3 and 4 below. [Table 3] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 static coefficient of friction during initial sliding 0.35 0.33 0.17 0.3 0.16 0.17 dynamic coefficient of friction during first sliding 0.14 0.14 0.11 0.13 0.1 0.12 Evaluation of static friction coefficients ○ ○ ○ ○ ○ ○ static coefficient of friction at one hundredth sliding 0.34 0.32 0.18 0.25 0.16 0.19 dynamic coefficient of friction at hundredth sliding 0.14 0.14 0.12 0.13 0.1 0.14 durability ○ ○ ○ ○ ○ ○ [Table 4] Comparative example 1 Comparative example 2 Comparative example 3 Comparative example 4 Comparative example 5 Comparative example 6 Comparative example 7 Comparative example 8 Comparative example 9 static coefficient of friction during initial sliding 0.19 0.14 0.3 0.13 0.14 0.13 0.19 0.08 0.06 dynamic coefficient of friction during first sliding 0.12 0.1 0.19 0.1 0.09 0.1 0.12 0.05 0.04 Evaluation of static friction coefficients ○ × ○ × × × ○ × × static coefficient of friction at one hundredth sliding 0.24 0.15 0.32 0.14 0.16 0.15 0.22 0.09 0.08 dynamic coefficient of friction at hundredth sliding 0.17 0.11 0.22 0.11 0.12 0.12 0.16 0.06 0.05 durability × × × × ○ × × × ×

[0046] Table 1 showed that in embodiments 1 to 6, the base oil was a synthetic hydrocarbon oil with a kinematic viscosity of 600 to 2000 mm². 2 The operating temperature is / s at 40°C, the thickening agent is a barium complex soap, and the solid lubricant consists of inorganic fine particles with a Mohs hardness of 3 to 6 and an average particle size of 10 to 40 µm, thus providing a high static coefficient of friction and excellent durability. However, embodiment 6 is not encompassed by the invention as defined in the claims.

[0047] In contrast, in comparison example 1, the kinematic viscosity of the base oil at 40°C is less than 600 mm². 2 When the viscosity is / s, a grease composition with poor durability was obtained. Since, in comparison example 2, the kinematic viscosity at 40°C of the base oil is 2000 mm², 2 Since the Mohs hardness of the solid lubricant exceeded 6 in comparison example 3, a grease composition with a low static coefficient of friction and poor durability was obtained. Since the Mohs hardness of the solid lubricant in comparison example 4 is less than 3, a grease composition with a low static coefficient of friction and poor durability was obtained. Since the thickener in comparison example 5 is a lithium soap, the static coefficient of friction was low. Since the average particle size of the solid lubricant in comparison example 6 is less than 10 µm, a grease composition with a low static coefficient of friction and poor durability was obtained.Since the average particle size of the solid lubricant in comparison example 7 exceeds 40 µm, a grease composition with poorer durability was obtained. Since the solid lubricant in comparison example 8 is an organic substance, a grease composition with a low static coefficient of friction and poor durability was obtained. Since the kinematic viscosity of the base oil at 40°C is less than 600 mmHg in comparison example 9. 2 Given that the coefficient of friction (CFR) is / s, the thickening agent is a lithium soap, and the solid lubricant is an organic substance, a grease composition with a low static coefficient of friction and poor durability was obtained.

[0048] The lubricating grease composition according to the present invention therefore comprises one or more base oils, one or more thickening agents and one or more solid lubricants, wherein the base oil is a synthetic hydrocarbon oil with a kinematic viscosity of 600 to 2000 mm². 2 The grease composition is defined as follows: the viscosity at 40°C, the thickening agent being one or more barium complex soaps, and the solid lubricant being inorganic fine particles with a Mohs hardness of 3 to 6 and an average particle size of 20 to 40 µm. Furthermore, the content of the thickening agent, i.e., the one or more barium complex soaps, is 10 to 30 wt.%, based on the total weight of the grease composition, according to the exemplary embodiments. As a result, the grease composition according to the present invention exhibits an overall high static coefficient of friction and excellent durability.

[0049] The lubricating grease composition according to the present invention is particularly suitable for use in a sliding section between resin parts or between a resin part and a metal part, so that it can be applied to devices, components, etc., in various industrial fields. A sliding section of a coupling is preferably used as the sliding section between resin parts or between a resin part and a metal part. Although the devices on which the coupling is mounted are not particularly limited, a window regulator motor can be cited as an example. For example, a coupling mounted in the window regulator motor could be...A coupling to prevent reverse rotation is provided, which connects a rotary shaft for generating a rotary drive force of the window lift motor to a worm shaft of a reduction mechanism to reduce the rotary drive force transmitted by the rotary shaft and to prevent reverse rotation of the motor due to an external force.

[0050] The lubricating grease composition is also widely applicable to, for example, the following: components for office machines, such as copiers and printers, etc.; power transmission mechanisms such as reduction / transmission gears, gears, chains, motors, etc.; driving system components; braking system components such as ABS (anti-lock braking system), etc.; steering system components; drive system components such as transmissions, etc.; vehicle reinforcement components such as window regulator motors, seat motors, sunroof motors, etc.; electronic information devices; hinge components such as those in mobile phones, etc.; as well as various components and machine parts, etc., that move relative to one another, in the food and pharmaceutical industries, steel, construction, glass, cement, chemical, rubber, and resin industries such as film stretching devices, etc.; environmental equipment and power plants; the paper and printing industry; the wood industry; and the textile and clothing industry. Furthermore, it is used on bearings, etc.such as rolling bearings, axial bearings, dynamic bearings, resin bearings, linear motion devices, etc. are also possible.< / rostinhibitor> < / antioxidationsmittel> < / festschmierstoff> < / verdickungsmittel>

Claims

[1] Grease composition containing one or more base oils, a thickening agent and one or more solid lubricants, wherein the base oil is a synthetic hydrocarbon oil with a kinematic viscosity of 600 to 2000 mm² 2 / s at 40°C is, the thickening agent is one or more barium complex soaps, as well as The solid lubricant consists of inorganic fine particles with a Mohs hardness of 3 to 6 and an average grain size of 20 to 40 µm. wherein the solid lubricant content is 10 to 60 wt.% based on the total weight of the lubricating grease composition, and wherein the content of one or more barium complex soaps is 10 - 30 wt.%, based on the total weight of the lubricating grease composition. [2] Use of the lubricating grease composition according to claim 1 for a sliding section between resin parts or between a resin part and a metal part. [3] Use of the lubricating grease composition according to claim 2, wherein the sliding section is a sliding section of a coupling. [4] Use of the lubricating grease composition according to claim 1 in a window regulator motor with a clutch.