| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a foamed elastic product that permits direct formation of a surface resin layer by application on an elastic layer composed of a polyurethane foam to give an electroconductive roller such as a developing roller while omitting formation of an undercoat layer. <P>SOLUTION: The polyurethane foam is manufactured by the mechanical blowing of a polyurethane raw material, wherein the polyurethane foam comprises a polymer polyol containing polyether polyol composed of propylene oxide and ethylene oxide, polystyrene or polyacrylate and having a hydroxy value of 20-60 mgKOH, an ethylene oxide content of 1-20 mass% and an average functional group number of 2.5-3 and at least one of modified TDI, modified MDI and modified HDI having an NCO content of 1-25%, and has the number of holes on the surface of the polyurethane foam of at most 4/mm<SP>2</SP>with an average hole diameter of at most 0.1 mm. <P>COPYRIGHT: (C)2009,JPO&INPIT |
