摘要 |
<p>A polyester film having a coating layer provided with excellent mold release property, slipperiness, heat resistance and flatness is disclosed. The laminated polyester film is prepared by applying at least on one surface of a polyester film an aqueous solution or dispersion containing a polysiloxane-polyvinyl graft copolymer which comprises a silane comprising structural units of the formulas (1) and (2) indicated below or the hydrolysate thereof and in which not less than 80 wt% of the siloxane portions are dimethylsiloxane, and, thereafter, stretching and drying. R1nSiO(4-n) (1) R2mSiO(3-m)2- A - B (2) wherein R1 and R2 are respectively and independently an unsubstituted or substituted hydrocarbyl group which has a carbon atom directly connected to the Si atom and has no radical polymerizability; n is 1 or 2 and when n is 2 R1's may be different groups; m is 0 or 1; A is a divalent organic group which has a carbon directly connected to the Si atom and is connected to the group B; and B is a vinyl copolymer block obtained by grafting at least one selected from an aromatic vinyl monomer and an alkyl ester of acrylic or methacrylic acid.</p> |