Novel Co-Modified Organopolysiloxane

A co-modified organopolysiloxane having a group with a siloxane dendron structure and a hydrophilic group, expressed by the following general formula (1)2

• General Formula (1):
• R1aL1bQcSiO(4-a-b-c)/2 (1)
• wherein,
• R1 is a monovalent organic group with the exception of groups corresponding to L1 or Q, or a hydrogen atom;
• L1 is a silylalkyl group having a siloxane dendron structure expressed by the following general formula (2) when i=1;
• wherein, R1 is synonymous with the group described above, R2 is a phenyl group or an alkyl group having from 1 to 6 carbons, and Z is a divalent organic group;
• i represents a generation of the silylalkyl group represented by Li, and is an integer of 1 to c when c is a number of generations that is a number of repetitions of the silylalkyl group, the number of generations c is an integer from 1 to 10, and Li+1 is the silylalkyl group when i is less than c and is a methyl group or a phenyl group when i=c;
• ai is a number in a range of 0 to 3;
• Q is a hydrophilic group bonded to the silicon atom via a linking group that is at least divalent, and comprises at least one hydrophilic unit selected from hydrophilic units expressed by the following structural formulae (3-1) to (3-4):
• —CrH2r—O— (3-1)
• wherein r is a number in a range of 1 to 6;
• wherein W is a hydrogen atom or an alkyl group having from 1 to 20 carbons;
• wherein W is synonymous with the group described above;
• and
• wherein a, b, and c are in a range so that 1.0≦a≦2.5, 0.001≦b≦1.5, and 0.001≦c≦1.5.