Patent ID: 11905486
Assignee: IDEMITSU KOSAN CO., LTD.
Field: Basic materials chemistry (Chemistry)
Classification: CPC C | IPC C

Claim 2:
3. The viscosity index improver composition according to claim 1, wherein the comb-shaped polymer (A) further comprises a structural unit derived from a monomer (A2) represented by the following general formula (a2):, wherein in the general formula (a2):
R21 represents a hydrogen atom or a methyl group;
R22 represents a single bond, —O—, or —NH—;
R23 represents a linear alkylene group having 2 to 4 carbon atoms or a branched alkylene group having 2 to 4 carbon atoms;
m2 represents an integer of 1 to 20, in which in the case where m2 represents an integer of 2 or more, plural groups represented by R23 may be the same as or different from each other, and the (R23O)m2 moiety may be either random copolymerization or block copolymerization; and
R24 represents a linear alkyl group having 1 to 12 carbon atoms or a branched alkyl group having 1 to 12 carbon atoms.