| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lightweight easy-to-handle backing material which has low density and low hardness and is formed of a polyurethane foam quickly at a low price not through a troublesome process of sticking a continuous air permeable polyurethane sheet and thermosetting polyurethane foam together using an adhesive by applying the thermosetting polyurethane foam to the continuous air permeable polyurethane sheet and foaming the thermosetting polyurethane foam by heating. <P>SOLUTION: There is provided the continuous air permeable polyurethane sheet of 5-100 μm in thickness and 840-1,210 kg/m<SP POS="POST">3</SP>in density having fine pores including long holes of 2.0 μm or smaller which is formed on one surface side thereof in one body by thermal fusing. The other surface side of the thermosetting polyurethane foam is fixed to a surface plate for holding an object to be polished, and the other surface side of the continuous air permeable polyurethane sheet is brought into contact with the object to be polished. <P>COPYRIGHT: (C)2013,JPO&INPIT |
