Transmission fluid

Patent metadata

Field	Value
Publication number	US-2016208192-A1
Application number	US-201414913866-A
Country	US
Kind code	A1
Filing date	Sep 8, 2014
Priority date	Sep 9, 2013
Publication date	Jul 21, 2016
Grant date	—

Abstract

A transmission fluid contains a base oil and calcium carbonate. The calcium carbonate is dispersed in a form of aggregations in the transmission fluid. A ratio of the aggregations having a particle diameter of 200 nm or more is 28 mass % or less in terms of calcium based on a total amount of the aggregations. A base value of the transmission fluid is in a range from 0.5 mgKOH/g to 3 mgKOH/g by a hydrochloric acid method.

First claim

1 . A transmission fluid comprising:
a base oil; and calcium carbonate, wherein the calcium carbonate is dispersed in a form of aggregations in the transmission fluid, a ratio of the aggregations having a particle diameter of 200 nm or more is 28 mass % or less in terms of calcium based on a total amount of the aggregations, and a base value of the transmission fluid is in a range from 0.5 mgKOH/g to 3 mgKOH/g by a hydrochloric acid method.

2 . The transmission fluid according to claim 1 , wherein
the calcium carbonate is derived from an overbased organic acid calcium salt compound, and a content of the calcium carbonate is a range from 0.001 mass % to 0.3 mass % in terms of calcium based on a total amount of the transmission fluid.

3 . The transmission fluid according to claim 2 , wherein
the overbased organic acid calcium salt compound is an overbased detergent, and the overbased detergent is at least one selected from the group consisting of a sulfonate detergent, a salicylate detergent and a phenate detergent.

4 . The transmission fluid according to claim 1 , wherein the base oil comprises polyalphaolefin.

5 . The transmission fluid according to claim 4 , wherein a ratio of the polyalphaolefin in the base oil is 30 mass % or more.

6 . The transmission fluid according to claim 4 , wherein the polyalphaolefin has a kinematic viscosity at 100 degrees C. in a range from 2 mm 2 /s to 200 mm 2 /s.

7 . The transmission fluid according to claim 1 , wherein
the transmission fluid has a kinematic viscosity at 100 degrees C. in a range from 3 mm 2 /s to 8 mm 2 /s, and the transmission fluid has a viscosity index of 100 or more.

8 . The transmission fluid according to claim 1 , wherein the transmission fluid is suitable for an automatic transmission or a continuously variable transmission.

Assignees

• Idemitsu Kosan Co

Inventors

• Iwai Toshiaki

Classifications

• C10N2040/045

  for continuous variable transmission [CVT] · CPC title

• C10N2020/06

  Particles of special shape or size · CPC title

• C10M169/042

  the additives being compounds of unknown or incompletely defined constitution only · CPC title

• C10N2010/04

  Groups 2 or 12 · CPC title

• C10M105/04

  aliphatic · CPC title