Stretchable film and method for forming the same

A method for forming a stretchable film comprising:

• forming a silicone-pendant type urethane layer having a structure shown by the following general formula (2)-1 and/or (2)-2 through curing by heating and/or light exposure;
• and
• forming a silicone main-chain type urethane layer having a structure shown by the following general formula (1)-1 and/or (1)-2 on a surface of the silicone-pendant type urethane layer through curing by heating and/or light exposure:
• wherein R1 and R4 each represent a linear or branched alkylene group having 1 to 40 carbon atoms optionally containing an ether group or a thiol group;
• R2, R3, and R5 represent the same or different linear, branched, or cyclic alkyl group having 1 to 6 carbon atoms, a phenyl group, or a 3,3,3-trifluoropropyl group;
• R6, R11, R12, and R13 represent the same or different linear, branched, or cyclic alkyl group having 1 to 6 carbon atoms, a phenyl group, a 3,3,3-trifluoropropyl group, or a —(OSiR2R3)s—OSiR2R3R5 group;
• R7 and R9 each represent a single bond, a methylene group, or an ethylene group, provided that the total number of the carbon atoms of R7 and R9 is 1 or 2;
• R8 represents a hydrogen atom or a linear alkyl group having 1 to 4 carbon atoms;
• R10 represents a hydrogen atom or a methyl group;
• “A” represents a linear or branched alkylene group having 3 to 7 carbon atoms;
• X represents a linear or branched alkylene group having 3 to 7 carbon atoms optionally containing an ether group;
• “m” and “n” are each an integer in the range of 1 to 100;
• “p” is an integer in the range of 2 to 10;
• and “q”, “r”, and “s” are each an integer in the range of 0 to 20.