Patent ID: 8575380

Claim:
Branched polyethylene glycol which is represented by the following formula (1) and which is bound to a diacylglycerol: wherein R 1 is a hydrocarbon group containing 1 to 7 carbon atoms, R 2 is an alkyl or alkenyl group containing 9 to 21 carbon atoms, n is the average number of moles of added polyethylene glycol chains, 10≦n≦100, and X is a linker site between branched polyethylene glycol and the diacylglycerol and is represented by the following formula (2): —(CH 2 ) l -Y—(CH 2 ) m - (2) where Y is an ether bond, an ester bond, a urethane bond, an amide bond, or a carbonate bond and l and m are an integer of 0 to 6.