Patent ID: 7645849

Claim:
A cleaning blade member comprising a polyurethane formed by using a polyol consisting essentially of a polycarbonatediol, a polyisocyanate consisting essentially of 4,4′-diphenylmethane diisocyanate (MDI), and a crosslinking agent containing a short chain diol and a triol, wherein the proportion of the polyisocyanate is 40 to 50 parts by weight based on 100 parts by weight of the polyurethane, and, said polyurethane having a tensile strength at 60° C. of 200 kg/cm 2 or higher, and a tensile strength retention ΔT, represented by the following equation, of 40% or more: Δ T (%)= T 60 /T 10 ×100 where T 10 denotes a tensile strength at 10° C., and T 60 denotes the tensile strength at 60° C.