| abstract |
(57) [Problem] To provide a composite film having sufficient breaking strength, good stress relaxation property, and excellent workability. SOLUTION: The composite film is obtained by irradiating a mixture containing a urethane polymer and a radical polymerizable monomer as main components by irradiating the mixture with 100% mod of 5N. / Mm 2 or more, elongation at break of 150% or more, and a stress relaxation time of 200 seconds or less. |