Patent ID: 7619052

Claim:
A blade for an electrophotographic apparatus comprising a support member and joined thereto a blade member formed of a polyurethane resin, wherein: the polyurethane resin is a resin produced by using a polyurethane raw-material composition containing at least the following components (A) to (E): (A) a polyisocyanate; (B) a polyol having a number average molecular weight of 2,000 or more and 4,000 or less, wherein the polyol is adipate diol; (C) a chain extender having a molecular weight of 200 or less; (D) a polyol having a number average molecular weight of 200 or more and 1,200 or less which is between (B) polyol and (C) chain extender, wherein the polyol is adipate diol; and (E) a urethane curing catalyst comprising an isocyanurating catalyst, wherein the ratio of the mass of the component (B) polyol to the mass of the component (D) polyol, (D)/(B), which components are contained in the polyurethane raw-material composition, is 0.02 or more and 0.25 or less, and wherein the polyurethane raw-material composition has a polyisocyanate (A) group concentration (mmol/g) of 1.80 or more and 2.63 or less as calculated according to the following expression: NCO=1,000 ×F n ×W iso /( Mn iso ×W all ) where NCO represents the isocyanate group concentration (mmol/g); F n , the number of isocyanate groups per molecule of the component (A) polyisocyanate; W iso , the amount (g) in which the component (A) polyisocyanate is mixed; Mn iso , the number average molecular weight of the component (A) polyisocyanate; and W all , the total mass (g) of the components (A) to (E).