Grease composition

• US 8,183,191 B2
• Filed: 04/22/2003
• Issued: 05/22/2012
• Est. Priority Date: 04/26/2002
• Status: Active Grant

• Current Assignee: Nippon Oil Corporation (ENEOS Holdings, Inc.)
• Original Assignee: Nippon Oil Corporation (ENEOS Holdings, Inc.)
• Inventors: Kinoshita, Hirotsugu, Nomura, Souichi, Arai, Takashi, Sakamoto, Kiyomi
• Primary Examiner(s): Goloboy, Jim
• Application Number:
  US10/512,584
• Publication Number:
  US 20050209115A1
• Time in Patent Office: 3,318 Days
• Field of Search: 508/552, 508/442, 508/528, 508/577
• US Class Current: 508/528
• CPC Class Codes: C10M 169/06 Mixtures of thickeners and additives
• CPC Class Codes: C10M 2205/12 Oxidised hydrocarbons, i.e. oxidised subsequent to macromolecular formation
• CPC Class Codes: C10M 2205/16 Paraffin waxes; Petrolatum, e.g. slack wax
• CPC Class Codes: C10M 2215/1026 used as thickening material
• CPC Class Codes: C10M 2219/068 Thiocarbamate metal salts
• CPC Class Codes: C10M 2223/00 Organic non-macromolecular compounds containing phosphorus as ingredients in lubricant compositions
• CPC Class Codes: C10M 2223/045 Metal containing thio derivatives
• CPC Class Codes: C10M 2223/049 Phosphite
• CPC Class Codes: C10N 2010/12 Groups 6 or 16
• CPC Class Codes: C10N 2030/06 Oiliness; Film-strength; Anti-wear; Resistance to extreme pressure
• CPC Class Codes: C10N 2040/04 Oil-bath; Gear-boxes; Automatic transmissions; Traction drives
• CPC Class Codes: C10N 2060/04 Oxidation, e.g. ozonisation

Abstract

A grease composition containing a lubricant base oil, diurea compounds represented by the following general formulas (1) to (3), and at least one species selected from the group consisting of paraffin oxides and phosphorus compounds; wherein respective contents of the diurea compounds represented by the following general formulas (1) to (3) satisfy conditions defined by the following expressions (4) and (5); and wherein the total content of the paraffin oxides and phosphorus compounds is 0.1 to 15 mass % based on the total amount of the grease composition:

where R¹ is a hydrocarbon group containing an aromatic ring, R² is a divalent hydrocarbon group, and R³ is a hydrocarbon group containing an aliphatic ring;
5≦W₁+W₂+W₃≦30  (4)
0.3≦(W₁+0.5×W₂)/(W₁+W₂+W₃)≦0.7  (5)
where W₁, W₂, and W₃ are respective contents (mass %) of the diurea compounds represented by general formulas (1) to (3) based on the total amount of the grease composition.

Claims

1. A grease composition containing a lubricant base oil, diurea compounds represented by the following general formulas (1) to (3), an ester of paraffin oxide having a total acid number of 0.2-65 mgKOH/g and at least one phosphite ester selected from phosphite diesters;

wherein respective contents of the diurea compounds represented by the following general formulas (1) to (3) satisfy conditions defined by the following expressions (4) and (5); and

wherein the total content of the ester of pamraffin oxide and the phosphite ester is not greater than 4.5 mass %, the content of the ester of paraffin oxide is at least the 1 mass %, and the content of the phosphite ester is 0.5 mass % to 1.0 mass % based on the total amount of the grease composition;

2. The grease composition according to claim 1, wherein the ester of paraffin oxide is formed between an alcohol having a carbon number of 1 to 24 and paraffin oxide.

3. The grease composition according to claim 1, wherein the total acid number of the ester of paraffin oxide is 1 to 40 mgKOH/g.