PURPOSE: To provide the title grease which prevents insulation deterioration due to adhesion of carbonized powder formed by arc heat generated when a switch is put on or off, and which comprises a particular base oil, an ethylene/α-olefin copolymer, a metal salt of a higher fatty acid and a polybutene.
CONSTITUTION: 100pts.wt. (hereinafter simply pts.) base oil (A) i.e., an ethylene/α- olefin oligomer which is cooligomer of 30W70mol.% ethylene with a 3W20 C olefin and has a no.-average MW of 300W2,000 and a viscosity of 40W2,000 cSt (100°C), 0.1W5pts. viscosity builder (B), i.e., an ethylene/α-olefin copolymer which has an ethylene content of 40W60wt.% and an average MW of several tens of thousands to several hundreds of thousands, 5W30pts. thickening agent (C), i.e., a metal salt of a higher fatty acid pref. selected from lithium stearate and/or lithium 12-hydroxystearate, and 5W30pts. polybutene (D) of 500W3,000 in MW which undergoes complete depolymerization at 300W400°C without formation of carbon residue, and optionally 1W10wt.% high m.p. wax (E) are mixed together.
OOTAKE SUGAKO
| JPS6031598A | 1985-02-18 | |||
| JPS50151903A | 1975-12-06 |