TRANSPARENT LAMINATED FILM AND METHOD FOR PRODUCING THE SAME
A transparent laminated film is provided with which it is possible to inhibit peeling of thin film layers, even with long-term exposure to sunlight during use and exposure to UV rays during quality evaluation. The film has a thin film layer obtained by lamination of multiple thin films on at least one side of a transparent polymer film. This thin film layer has metal oxide thin films formed by a sol-gel process using light energy during sol-gel hardening and post-oxidation thin films formed by post-oxidation of at least one thin film selected from metal thin film, alloy thin film, and partially oxidized metal oxide thin film.
1 . A transparent laminated film production method comprising:
a lamination process forming, on at least one surface of a transparent polymer film, a thin film layer containing a metal oxide thin film formed by a sol-gel method using light energy during sol-gel hardening, and at least one kind of thin film selected from a metal thin film, an alloy thin film, and a partially oxidized metal oxide thin film; and
a post-oxidation process forming a post-oxidation thin film by post-oxidizing the at least one kind of thin film selected from the metal thin film, the alloy thin film, and the partially oxidized metal oxide thin film, the post-oxidation thin film being contained in the thin film layer.
2 . The transparent laminated film production method according to claim 1 , wherein the post-oxidation process is performed by post-oxidizing the transparent polymer film having the thin film layer.
3 . The transparent laminated film production method according to claim 2 , wherein the transparent polymer film having the thin film layer is wound in a roll-like form.
4 . The transparent laminated film production method according to claim 1 , wherein the post-oxidation is performed via a heat treatment.
5 . The transparent laminated film production method according to claim 4 , wherein a heating temperature during the heat treatment is equal to or below a softening temperature of a material constituting the transparent polymer film having the thin film layer.
6 . The transparent laminated film production method according to claim 5 , wherein the heating temperature is 30° C.-60° C.
7 . The transparent laminated film production method according to claim 1 , wherein:
the metal thin film is a metal Ti thin film;
the alloy thin film is a silver alloy thin film; and
the partially oxidized metal oxide thin film is a partially oxidized titanium oxide thin film.
8 . The transparent laminated film production method according to claim 7 , wherein the silver alloy contains at least one kind of element selected from Cu, Cr, Fe, Ni, Pb, Si, Ti, V, Y, and Zr, as secondary alloy elements.
9 . The transparent laminated film production method according to claim 7 , wherein the silver alloy is one of an Ag—Cu alloy and an Ag—Ti alloy.