KR20190012737A - Grease composition - Google Patents

Abstract

The present invention provides a grease composition comprising 70-80 parts by weight of base oil, 10-20 parts by weight of a urea-based thickener, and 1-10 parts by weight of a phosphate compound based on the total weight of the grease composition. The grease composition according to an embodiment of the present invention can enhance wear resistance, heat resistance and the like, so the composition has stable and excellent performance and increased lifetime even at a high temperature and high speed rotation.

Description

Grease composition {GREASE COMPOSITION}

The present invention relates to a grease composition.

Lubricating greases are widely used in the automotive industry, conveyor technology, mechanical engineering, office equipment, industrial plants and machinery, as well as in household products and recreational electronics.

In particular, the grease used in roller bearings or friction bearings separates the two parts between the friction and sliding surfaces and forms an oil film carrying the load. Thereby, it is possible to prevent the metal surfaces from being abraded by friction. These greases must meet high requirements, such as when used at very high or low rotational speeds, high temperatures due to high-speed rotation or long-time heating, or bearing, aerospace, Lubricants should work normally under very low temperature conditions.

In general, for example, high-speed bearings at the level of 2000 to 8000 rpm have been widely applied to improve efficiency throughout the industrial field, and various types of grease have been applied accordingly. These greases for high-speed bearings are generally made of synthetic oil, urea or lithium thickener rather than low-cost mineral oil so that lubrication life can be ensured even under a high temperature environment.

At present, due to the development and development of the automobile industry, the use of electric motors has increased and the rotation speed of the motors has been remarkably increased. As a result, the grease for existing bearings has a shear safety at high temperature, And abrasion-preventing properties. As a result, such properties as long life and low vibration can not be satisfied.

Therefore, in order to solve the above-mentioned conventional problems, it is necessary to develop a grease composition capable of enhancing thermal characteristics at high temperature and high speed rotation, minimizing friction wear of bearings, and realizing long life characteristics and excellent physical properties.

Japanese Laid-Open Patent Application No. 2014-019742

A technical object of the present invention is to provide a grease composition capable of improving long life characteristics, heat resistance and abrasion resistance even at high temperature and high rotation.

The present invention relates to a grease composition comprising 70 to 80 parts by weight of a base oil, 10 to 20 parts by weight of a urea thickener, and 1 to 10 parts by weight of a phosphate compound, based on the total weight of the grease composition, Lt; / RTI >

The grease composition according to an embodiment of the present invention can improve abrasion resistance and heat resistance even at high temperature and high speed rotation, and can realize stable and long-lived lubricity even under high-speed conditions.

Hereinafter, the present invention will be described in detail in order to facilitate understanding of the present invention.

The terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms and the inventor may appropriately define the concept of the term in order to best describe its invention It should be construed as meaning and concept consistent with the technical idea of the present invention.

The grease composition according to one embodiment of the present invention comprises 70 to 80 parts by weight of base oil, 10 to 20 parts by weight of a urea thickener, and 1 to 10 parts by weight of a phosphate compound, based on the total weight of the grease composition do.

The grease composition according to one embodiment of the present invention can improve thermal properties and high temperature performance by using a base oil and a urea thickener, and by including a phosphate compound, friction wear can be minimized, Stable and excellent performance can be realized and the lifetime can be increased.

Hereinafter, the present invention will be described in more detail.

The grease composition according to one embodiment of the present invention includes a base oil, a urea-based thickener, and a phosphate-based compound, each of which is described in detail below.

A. Base oil

The base oil included in the grease composition according to an embodiment of the present invention may include a mixture oil of (A1) ester and (A2) polyalphaolefin (PAO) to enhance thermal properties and improve high temperature service life.

Examples of the ester (A1) include polyol esters, aliphatic diesters and aromatic esters.

Examples of the polyol ester include esters of an aliphatic polyhydric alcohol and a linear or branched fatty acid. Examples of the aliphatic polyhydric alcohol forming the polyol ester include neopentylglycol, trimethylolpropane, ditrimethylolpropane, trimethylolethane, ditrimethylolethane, pentaerythritol, dipentaerythritol, dipentaerythritol, . As the fatty acid, those having 4 to 22 carbon atoms can be used. Specific examples of the fatty acid include butane, hexanoic, pelargonic, capric, undecyl, lauric, , Isostearic acid, and tridecylic acid. In addition, partial esters of the above-mentioned aliphatic polyhydric alcohol with linear or branched fatty acids can also be used. These partial esters are obtained by appropriately adjusting the reaction mole number of the aliphatic polyhydric alcohol and the fatty acid to react.

Such a polyol ester may have a kinematic viscosity at 100 ° C of not less than 1 mm 2 / s and not more than 50 mm 2 / s, specifically not less than 2 mm 2 / s and not more than 40 mm 2 / s, more specifically not less than 3 mm 2 / s < / RTI > If the kinematic viscosity is 1 mm < 2 > / s or more, the evaporation loss may be small. When the kinematic viscosity is 50 mm < 2 > / s or less, energy loss due to viscous resistance is suppressed.

As the aliphatic diester, an aliphatic dibasic acid diester is preferably used. As the carboxylic acid component of the aliphatic dibasic acid diester, a linear or branched aliphatic dibasic acid having 6 to 10 carbon atoms is preferable. Specific examples thereof include adipic acid, pimelic acid, suberic acid, azelaic acid, Sebacic acid, and those having properties equivalent to these. As the alcohol component, aliphatic alcohols having 6 to 18 carbon atoms are preferable, and specific examples thereof include hexyl alcohol, heptyl alcohol, octyl alcohol, nonyl alcohol, decyl alcohol, undecyl alcohol, dodecyl alcohol, tridecyl alcohol, Alcohols and pentadecyl alcohols, and isomers thereof.

The aliphatic diester preferably has a kinematic viscosity at 100 ° C of not less than 1 mm 2 / s and not more than 50 mm 2 / s, more preferably not less than 1.5 mm 2 / s and not more than 30 mm 2 / s, s or less. When the kinematic viscosity is 1 mm 2 / s or more, the evaporation loss is small, and when the kinematic viscosity is 50 mm 2 / s or less, the energy loss due to viscous resistance is suppressed and the starting property and the rotatability are excellent at low temperature.

As the aromatic ester, esters of various types of carboxylic acids and alcohols such as aromatic monobasic acids, aromatic dibasic acids, aromatic tribasic acids and aromatic tetrabasic acids can be used. Examples of the aromatic dibasic acids include phthalic acid and isophthalic acid. Examples of the aromatic tribasic acid include trimellitic acid and the like. Examples of the aromatic tetrabasic acid include pyromellitic acid and the like. Concretely, aromatic ester oils such as trioctyl trimellitate, tridecyl trimellitate and tetraoctyl pyromellitate are preferably used.

Such aromatic esters preferably have a kinematic viscosity at 100 ° C of not less than 1 mm 2 / s and not more than 50 mm 2 / s, more preferably not less than 1.5 mm 2 / s and not more than 30 mm 2 / s, Or less. When the kinematic viscosity is 1 mm 2 / s or more, the evaporation loss is small, and when the kinematic viscosity is 50 mm 2 / s or less, the energy loss due to viscous resistance is suppressed and the starting property and the rotatability are excellent at low temperature.

The above-mentioned polyol esters, aliphatic diesters and aromatic esters can be used alone or in combination with polyalphaolefins or both polyalphaolefins. It can also be used as a complex ester. Complex esters are esters synthesized from polybasic acids and polyhydric alcohols as raw materials. In general, raw materials include monobasic acids. In the present invention, an aliphatic polyhydric alcohol, a linear or branched aliphatic monocarboxylic acid having 4 to 18 carbon atoms, a straight chain or branched aliphatic dibasic acid, or an aromatic dibasic acid, a tribasic acid, or a tetrabasic acid Can be suitably used.

Examples of the aliphatic polyhydric alcohol used for forming the complex ester include trimethylolpropane, trimethylolethane, pentaerythritol and dipentaerythritol. Examples of the aliphatic monocarboxylic acid include aliphatic monocarboxylic acids having 4 to 18 carbon atoms, specifically, heptadecylic acid, stearic acid, nonadecanoic acid, arachic acid, behenic acid and lignoceric acid. . Examples of the aliphatic dibasic acids include succinic acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanoic acid, dodecanedioic acid, tridecanedioic acid, carboxyoctadecanoic acid, And Osan.

As the esterification reaction for producing the various esters described above, for example, an alcohol (monohydric or polyhydric alcohol) and a carboxylic acid (monobasic acid or polybasic acid) may be reacted at a predetermined ratio. Alternatively, partial esterification may be performed, then the partial esterified product may be reacted with a carboxylic acid, or the order of the acid reaction may be reversed, or an acid may be mixed to provide an esterification reaction.

On the other hand, the (A2) polyalphaolefin (PAO) is a polymer (oligomer) of an alpha olefin. The number of carbon atoms of the alpha olefin as a monomer is, for example, from 6 to 20, 16, and more specifically from 10 to 14.

The polyalphaolefin may be a dimer of an alpha olefin to a pentamer in view of low evaporability and energy saving. The polyalphaolefin can control the number of carbon atoms of the alpha-olefin, the mixing ratio thereof, and the degree of polymerization according to the desired properties.

As the polymerization catalyst of the alpha olefin, a BF ₃ catalyst, an AlCl ₃ catalyst, a Ziegler type catalyst, a metallocene catalyst, or the like can be used. Conventional, dynamic viscosity is 100 ℃ 30㎟ / s is less than a low-viscosity PAO, the BF ₃ catalyst is used, 30㎟ / s or more PAO has came the AlCl ₃ catalyst is used, from the viewpoint of low evaporation property and energy saving, in particular BF ₃ catalyst A metallocene catalyst may be used. The BF ₃ catalyst is used together with an accelerator such as water, alcohol or ester, but among them, it may be an alcohol, especially 1-butanol in terms of viscosity index, low-temperature properties and yield.

According to one embodiment of the present invention, the base oil has a ratio of polyalphaolefin to ester of 5:95 to 95: 5, specifically 50:50 to 93: 7, more specifically 70:30 to 80: : It can be 20 days.

The mixing base oil may have a kinematic viscosity at 100 ° C of 1 mm 2 / s or more and 30 mm 2 / s or less, specifically 2 mm 2 / s or more and 20 mm 2 / s or less. If the kinematic viscosity is 1 mm 2 / s or more, excellent lubricity and low evaporation loss are obtained. If the kinematic viscosity is 30 mm 2 / s or less, energy loss due to viscous resistance is suppressed, and excellent startability and rotability at low temperatures are obtained. The kinematic viscosity at 40 占 폚 may be 20 mm2 / s or more and 65 mm2 / s or less, specifically 20 mm2 / s or more and 50 mm2 / s or less.

The base oil may be 70 to 80 parts by weight based on the total weight of the grease composition. If the content of the base oil is less than 70 parts by weight, the lubricity and heat resistance may be poor. If the base oil is more than 80 parts by weight, durability may be deteriorated.

B. Urea thickener

The grease composition according to an embodiment of the present invention may include a urea thickener to increase heat resistance and high temperature service life. The urea-based thickener is excellent in heat resistance, and can improve not only braking resistance but also low friction properties.

The urea-based thickener may include, for example, a urea compound represented by the following general formula (1).

≪ Formula 1 >

In Formula 1,

R ₁ and R ₂ are each independently an aromatic hydrocarbon having 6 or 7 carbon atoms, a cyclohexyl group having 6 or 7 carbon atoms, or an aliphatic hydrocarbon having 6 to 20 carbon atoms. Specifically, R ₁ and R ₂ are each independently an aliphatic hydrocarbon having 6 to 20 carbon atoms, more specifically a 6 to 20 carbon chain aliphatic hydrocarbon. In the case where R ₁ and R ₂ in the above formula (1) are chain aliphatic hydrocarbons, it is possible to improve the shear safety and noise-preventing performance as compared with the case of containing an aromatic or non-aromatic cyclic hydrocarbon, It is possible to prevent the softening phenomenon and the noise of the grease caused by the heat. When the urea-based thickener containing the chain-like aliphatic hydrocarbon is used, deterioration at the time of high temperature and high-speed rotation and lifetime characteristics can be further improved as compared with the case of using a lithium-based thickener.

The urea-based thickener of Formula 1 may be prepared by reacting 1 equivalent of diisocyanate with 2 equivalents of alkyl, cyclo or arylamine in the presence of a lubricating oil. At this time, the urea thickener may control the heat resistance by changing the type of the amine used as the raw material, or may control the heat resistance by adjusting the mixing ratio of the amine to be mixed when using two or more amines. As the amine used in the present invention, aliphatic amines and alicyclic amines and mixtures thereof can be used.

Examples of the diisocyanate include 4,4-methylene bis (phenyl isocyanate). Examples of the amine include an aromatic amine or cyclohexylamine having 6 to 7 carbon atoms or an aliphatic amine having 6 to 20 carbon atoms .

The content of the urea-based thickener may be 10 to 20 parts by weight based on the total weight of the grease composition. If the content of the urea-based thickener is less than 10 parts by weight, the lead may become thinner and durability may deteriorate. Particularly, the effect of preventing deterioration at high temperatures may be insufficient. When the content is more than 20 parts by weight, There may be a problem of poor sex.

C. Phosphate-based compound

The grease composition according to one embodiment of the present invention may include a phosphate compound to prevent wear. Specifically, the phosphate-based compound may include an amine phosphate-based compound.

The amine phosphate-based compound may comprise tert-alkylamine-dimethyl phosphate, phenylamine-phosphate or mixtures thereof. At this time, the number of carbon atoms of the tert-alkylamine portion of the tert-alkylamine-dimethylphosphate is not particularly limited and may be, for example, 1 to 24.

The phosphate-based compound may include a phosphate-based compound containing a metal. However, in the case where a metal is not contained, the wear resistance of the bearing can be minimized and the temperature rise during rotation can be minimized to enable high-speed rotation. In addition, the bearing lubrication life can be increased.

According to one embodiment of the present invention, the phosphate compound may be contained in an amount of, for example, 1 to 10 parts by weight, specifically 2 to 5 parts by weight, based on the total weight of the grease composition. If the content of the phosphate compound is less than 1 part by weight, the effect of preventing abrasion may be insignificant. If the amount of the phosphate compound is more than 10 parts by weight, there is no further increase in the effect, so that it may not be economically or physically advantageous.

Also, according to an embodiment of the present invention, the mixing weight ratio of the ester base and the poly-alpha olefin to the mixed base oil and the phosphate base compound may be 95: 5 to 90:10. In the case of a grease composition having a mixing ratio in the above range, deterioration at high temperature and high temperature lifetime characteristics can be further improved.

D. Additives

According to one embodiment of the present invention, the grease composition may comprise various additives. The additive which can be added to the grease composition of the present invention can be used as long as it is commonly used in grease.

For example, the grease composition may comprise an antioxidant for antioxidation. The antioxidant may be a commonly used compound as long as it exhibits an antioxidant effect and does not impair the physical properties of the present invention. For example, an amine compound may be used. More specifically, Nn-butyl- Aminophenol, 4,4'-tetramethyldiaminodiphenylmethane, α-naphthylamine, N-phenyl-α-naphthylamine and phenothiazine.

The antioxidant may be contained in an amount of, for example, 1 part by weight to 5 parts by weight based on the total weight of the grease composition. If the content of the antioxidant is less than 1 part by weight, the antioxidant effect may be insufficient. If the amount is more than 5 parts by weight, the physical properties may be deteriorated due to excessive use.

In addition, the grease composition according to one embodiment of the present invention may contain a sulfonic acid salt compound for preventing corrosion.

The sulfonic acid salt-based compound may include a compound represented by the following formula (2)

(2)

[R ₄ -SO ₃ ] nM

In Formula 2,

R ₄ is an alkyl group, an alkenyl group, an alkylnaphthyl group, a dialkylnaphthyl group, an alkylphenyl group or a petroleum high boiling fractional residue,

M is an alkali metal, alkaline earth metal, zinc, or ammonium ion,

n is the mantissa of M.

Specifically, in R ₄ , the alkyl or alkenyl is linear or branched and has 2 to 22 carbon atoms. R ₄ is a dialkylnaphthyl group in which the number of carbon atoms in the alkyl group is, for example, 6 to 18, specifically 8 to 12,

The M may be an alkaline earth metal or zinc, and the alkaline earth metal may include calcium.

Also, n is a valence of M and is 1 to 2.

According to an embodiment of the present invention, the sulfonate-based compound may include at least one member selected from the group consisting of a zinc salt and a calcium salt. More specifically, the sulfonate-based compound may be dinonylnaphthalenesulfonic acid zinc salt and / or dinonylnaphthalenesulfonic acid calcium salt.

According to an embodiment of the present invention, the content of the sulfonic acid salt compound in the grease composition may be 0.5 to 5 parts by weight based on the total weight of the grease composition.

In addition, the above-mentioned grease composition may contain various additives in addition to the sulfonic acid salt-based compound as the above-mentioned antioxidant and the anticorrosive agent as well as the effect of the present invention.

The grease composition according to one embodiment of the present invention including the above components can improve abrasion resistance and heat resistance, and even when used for high-speed bearings at high temperatures of 140 DEG C or higher and 10,000 rpm or more, specifically 20,000 rpm or more, And can exhibit stable and excellent performance to increase the service life. In addition, since the grease composition has NLGI grade 2, i.e., 265 to 295, when it is measured according to the KS M ISO 2137 method, the lubricating function in the bearing can be easily realized. Therefore, the grease composition can be applied to a variety of applications such as an electric car and an industrial motor, and can be effectively used for high-efficiency energy saving and environment-friendly high-speed and high-load applications.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to examples. However, the embodiments according to the present invention can be modified into various other forms, and the scope of the present invention should not be construed as being limited to the embodiments described below. The embodiments of the present invention are provided to enable those skilled in the art to more fully understand the present invention.

Example

Example 1

Each component and content according to Table 1 below was used to prepare a grease composition.

Specifically, when the amine compound, amine phosphate compound, sulfonate salt compound and chain aliphatic urea thickener shown in Table 1 are measured by KS M 2014, the kinematic viscosity at 40 ° C is 53.38 mm 2 / s, 100 (Weight ratio of ester and polyalphaolefin is 70: 30 by weight, ester base oil is Hatcol 2932 by Hatco, PAO base oil is by Chevron Co., PAO6 product was used) to obtain a grease composition.

Example 2

A grease composition was obtained in the same manner as in Example 1, except that phosphate compound of dithiophosphate zinc salt (RC3180, manufactured by Rhein Chemie) was used as shown in Table 1 below.

Examples 3 to 4

A grease composition was obtained in the same manner as in Example 1 except that the content of the base oil and the phosphate base compound was changed as shown in Table 1 below.

Example 5

A grease composition was obtained in the same manner as in Example 1 except that metal dithiophosphate was used as the phosphate compound as shown in Table 1 below.

Example 6

A grease composition was obtained in the same manner as in Example 1 except that the sulfonic acid salt compound was not used as shown in Table 1 below.

Example 7

A grease composition was obtained in the same manner as in Example 1 except that an alicyclic urea thickener instead of the chain aliphatic urea thickener was used as shown in Table 1 below.

Comparative Example 1

Except that an ester oil having a kinematic viscosity of 80 mm 2 / s at 40 ° C. and a kinematic viscosity of 11 mm 2 / s at 100 ° C. was used instead of the mixed base oil as shown in Table 2 below and a phosphate compound was not used 1 to obtain a grease composition.

Comparative Example 2

An ester oil having a kinematic viscosity at 48 ° C of 48 mm 2 / s at 40 ° C and a kinematic viscosity of 7.6 mm 2 / s at 100 ° C was used instead of the mixed base oil as shown in Table 2 below, a lithium soap thickener was used as a thickener, The procedure of Example 1 was repeated to obtain a grease composition.

Comparative Example 3

A grease composition was obtained in the same manner as in Example 1 except that the phosphate compound was not used and the lithium complex thickener was used as shown in Table 2 below.

Comparative Examples 4 to 6

A grease composition was obtained in the same manner as in Example 1, except that the amount of the phosphate compound was changed as shown in Table 2 below.

Comparative Example 7

A grease composition was obtained in the same manner as in Example 1, except that a phosphorus phosphorus compound was used instead of the phosphate compound as shown in Table 2 below.

Comparative Example 8

As shown in the following Table 2, a mixed base oil of ether and polyalphaolefin having a kinematic viscosity at 40 DEG C of 65.21 mm < 2 > / s, a kinematic viscosity at 100 DEG C of 9.621 mm < 2 > / s and a viscosity index of 129 (ether is LB 100, MATSUMURA Co., And the olefin base oil was a product of PAO 6 manufactured by Chevron Co., Ltd.).

The compounds used in the examples and comparative examples of Tables 1 and 2 are as follows :

Ester oil: trimellitic ester

Ether system: alkyl diphenyl ether

PAO (poly alpha olefin):

Mixed base oils: Hatcol 2932 for ester base oils, PAO6 for Chevron base oils for PAO base oils

Chain aliphatic urea-based thickener:

Alicyclic urea-based thickener:

Lithium soap thickener: Lithium stearate

Lithium complex thickener: a mixture of lithium stearate and azelate

Phosphate compound 1: amine phosphate (IRGALUBE 349 from BASF)

Phosphate compound 2: dithiophosphate zinc salt (RC3180 from Rhein Chemie)

Phenylphosphorus compound: IRGALUBE TPPT (Triphenyl phosphorothionate)

Amine compound: Bis (4-octylphenyl) amine (RC7001 from Rhein Chemie)

Sulfonic acid salt compound: Calcium sulfonate (Alox 165 from Lubrizol)

ingredient Example 1
(Parts by weight) Example 2
(Parts by weight) Example 3
(Parts by weight) Example 4
(Parts by weight) Example 5
(Parts by weight) Example 6
(Parts by weight) Example 7
(Parts by weight) Base oil
ester
60 60 61 55 60 61 60 PAO 26 26 26 23 26 26 26 Chain type aliphatic urea thickener 10 10 10 10 10 10 Alicyclic urea thickener 10 Lithium-based thickener Antioxidant Amine compound One One One One One One One Abrasion inhibitor Phosphate compound 1 2 One 10 2 2 Phosphate compound 2 2 2 Corrosion inhibitor Sulfonic acid salt compound One One One One One One total 100 100 100 100 100 100 100

ingredient Comparative Example 1
(Parts by weight) Comparative Example 2
(Parts by weight) Comparative Example 3
(Parts by weight) Comparative Example 4
(Parts by weight) Comparative Example 5
(Parts by weight) Comparative Example 6
(Parts by weight) Comparative Example 7
(Parts by weight) Comparative Example 8
(Parts by weight) Base oil
ester 88 83 57 62 62 54 61 ether 43 PAO 24 26 26.2 23 26 43 Aliphatic urea-based thickener 10 10 10 10 10 10 Lithium-soap thickener 15 Lithium-complex solution 17 Antioxidant Amine compound One One One One One One One Abrasion inhibitor Phosphate compound 1
0.8 11 2 Phenylphosphorus compound One Corrosion inhibitor Sulfonic acid salt compound One One One One One One One One total 100 100 100 100 100 100 100 100

Experimental Example

The properties of the grease compositions prepared in the above Examples and Comparative Examples were measured as follows, and the results are shown in Tables 3 and 4.

1. Mixing lead: Measured according to KS M ISO 2137 method.

2. Stability of blend: Measured according to KS M 2051 method.

3. Redness: Measured according to KS M ISO 2176 method.

4. Reason: Measured according to KS M 2050 method.

5. Evaporation rate: Measured according to KS M 2037 method.

6. Copper corrosion: Measured according to KS M 2088.

7. Wear Resistance: 4-Ball Wear Diameter was measured according to ASTM D 2266.

8. Fusing load: Measured according to ASTM D 2596.

9. Low temperature torque: Measured according to KS M 2130.

10. Bearing life: Bearing life test was performed under the following conditions in accordance with ASTM D1741. Then, the time at which the bearing life was completed was measured, and the time was shown. When the test time is 2000 hours or more, it is determined to be acceptable. When the test time is 2000 hours or more, " 2000 <

Bearing type: 6306

Number of revolutions: 20,000 rpm

Test temperature: 150 ℃

Test load: 221N radial, 178N axial

Operating condition: Continuous

Properties unit Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 color - State of the Union State of the Union State of the Union State of the Union State of the Union State of the Union State of the Union Base oil Kinematic viscosity 40 ℃ Mm2 / s 5 3.38 53.38 53.38 53.38 53.38 53.38 53.38 100 ℃ 7.571 7.571 7.571 7.571 7.571 7.571 7.571 Viscosity index - 104 104 104 104 104 104 104 Mixed lead - 277 268 280 279 272 278 284 Blend stability - 37 52 39 61 41 45 40 Red dot ℃ > 280 > 280 > 280 > 280 > 280 > 280 > 280 Reason Wt% 1.1 1.4 1.8 2.0 2.2 2.1 1.2 Evaporation amount Wt% 0. 3 8 0.29 0.31 0.33 0.30 0.24 0.27 Copper plate corrosion grade 1b 2a 1b 2c 1b 1b 1b Wear in 4 Wear mm 0.38 0.44 0.51 0.41 0.47 0.49 0.40 Four Fused Load kgf 100 100 80 100 100 100 100 Bearing life time 2000 < 1420 1350 1510 1250 1140 2000 < Low temperature torque starting gf.cm 3,621 4301 3726 3744 4032 4112 3625 running gf.cm 914 1025 1005 983 1017 1107 908

Properties unit Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Comparative Example 7 Comparative Example 8 color - beige Light gray Light yellow Light yellow Light yellow Light yellow Light yellow Light yellow Base oil Kinematic viscosity 40 ℃ Mm2 / s 80 48 53.38 53.38 53.38 53.38 53.38 65.21 100 ℃ 11 7.6 7.571 7.571 7.571 7.571 7.571 9.621 Viscosity index
- - - 104 104 104 104 104 129 Mixed lead - 270 245 280 282 290 287 279 283 Blend stability - 54 67 49 47 52 49 58 49 Red dot ℃ > 280 > 280 > 280 > 280 > 280 > 280 > 280 > 280 Reason Wt% 1.6 0.5 1.3 1.8 2.0 2.4 1.8 1.7 Evaporation amount Wt% 0.21 0.42 0.41 0.35 0.29 0.31 0.35 0.29 Copper plate corrosion grade 1a 1a 1a 1b 1b 2a 1a 1b Wear in 4 Wear mm 0.71 0.97 0.53 0.64 0.43 0.55 0.51 0.55 Four Fused Load kgf 160 126 126 100 100 80 100 100 Bearing life time 1860 1750 1230 860 1780 1470 1220 1380 Low temperature torque starting gf.cm 3,971 3,627 2,867 3835 3642 3895 3811 4326 running gf.cm 771 859 1,283 995 891 972 1021 1325

As can be seen from Tables 3 and 4, Examples 1 to 7 of the present invention show improved physical properties such as blend stability, abrasion resistance, low-temperature torque, fusing load, and bearing life characteristics as compared with Comparative Examples 1 to 8 have.

Specifically, the compositions of Examples 1 to 7 exhibit remarkably small wear marks as compared with those of Comparative Examples 1 to 8, and it is confirmed that the wear resistance is very excellent, and the reason is also relatively low in comparison with the Comparative Examples, It was confirmed that it could be possible. Therefore, when using the grease composition according to one embodiment of the present invention, the bearing life test result can be as high as 2000 h (hour) or more, and the lubricating performance within a wide temperature range from low temperature to high temperature with low low- You can see that it is possible.

Claims (14)

With respect to the total weight of the grease composition,
70 to 80 parts by weight of a base oil,
10 to 20 parts by weight of a urea-based thickener, and
Phosphate compound 1 part by weight to 10 parts by weight
&Lt; / RTI &gt;
The method according to claim 1,
Wherein the phosphate-based compound comprises an amine phosphate-based compound.
The method of claim 2,
Wherein said amine phosphate-based compound comprises tert-alkylamine-dimethyl phosphate, phenylamine-phosphate, or mixtures thereof.
The method according to claim 1,
Wherein the urea-based thickener comprises a compound represented by the following formula (1):
&Lt; Formula 1 >

In Formula 1,
R ₁ and R ₂ are each independently an aromatic hydrocarbon having 6 or 7 carbon atoms, a cyclohexyl group having 6 or 7 carbon atoms, or an aliphatic hydrocarbon having 6 to 20 carbon atoms.
The method of claim 4,
Wherein R ₁ and R ₂ in Formula 1 are each independently a chain aliphatic hydrocarbon having 6 to 20 carbon atoms.
The method according to claim 1,
Wherein the weight ratio of the base oil and the phosphate base compound is from 95: 5 to 90:10.
The method according to claim 1,
Wherein the base oil comprises a blend of an ester and a polyalphaolefin (PAO).
The method of claim 7,
Wherein the weight ratio of the ester to the polar alpha-olefin is 70:30 to 80:20.
The method according to claim 1,
Wherein the grease composition further comprises an amine compound in an amount of 1 part by weight to 5 parts by weight.
The method of claim 9,
The amine compound may be selected from the group consisting of Nn-butyl-p-aminophenol, 4,4'-tetramethyldiaminodiphenylmethane,? -Naphthylamine, N-phenyl-? -Naphthylamine and phenothiazine And at least one selected.
The method according to claim 1,
Wherein the grease composition further comprises a sulfonate salt compound in an amount of 0.5 to 5 parts by weight.
The method of claim 11,
Wherein the sulfonate based compound comprises a compound of the following formula:
(2)
[R ₄ -SO ₃ ] nM
In Formula 2,
R ₄ is an alkyl group, an alkenyl group, an alkylnaphthyl group, a dialkylnaphthyl group, an alkylphenyl group or a petroleum high boiling fractional residue,
M is an alkali metal, alkaline earth metal, zinc, or ammonium ion,
n is the mantissa of M.
The method according to claim 1,
Wherein said grease composition is used for high speed bearings at 10,000 rpm or higher.
The method according to claim 1,
Wherein the grease composition has a miscibility index of from 265 to 295.