Surface-modified film, process for producing same, and laminated film and process for producing same
It is an object of the present invention to provide a surface-modified film which has adhesive properties improved by surface modification and a process for producing the same. It is also an object of the present invention to provide a laminated film in which at least the surface-modified film has been laminated and a process for producing the laminated film. The surface-modified film according to the present invention is characterized by being obtained by bringing a halide complex of an element in Group 13 of the periodic table into contact with at least a part of a region in the surfaces of a resin film.
1. A process for producing a surface-modified film, which is characterized by:
preparing a halide complex of an element in Group 13 of the periodic table by mixing an oxide of an element in Group 13 with a hydrogen halide or by contacting an anhydrous halide gas of an element in Group 13 with a solvent composed of a compound having a nucleophilic site in the molecule or by mixing an anhydrous liquid or solid halide of an element in Group 13 with a solvent composed of a compound having a nucleophilic site in the molecule;
bringing the halide complex of an element in Group 13 of the periodic table into contact with at least a part of a region in the surfaces of a resin film; and
washing the resin film with a washing solution at a temperature which is no lower than a melting point of the washing solution, no higher than a boiling point of the washing solution, and no higher than a heat-resistant temperature of the resin film, thereby to produce a surface-modified film having adhesive properties improved in a part of the region in the surfaces.
2. The process according to claim 1 , further comprising, after the washing step, drying the resin film by blowing nitrogen gas onto the surface thereof.
3. The process according to claim 2 , further comprising, after the nitrogen gas drying step, further drying the surface under reduced pressure of 10 Pa or less at room temperature.
4. The process according to claim 1 , wherein the washing step is conducted by immersing the resin film in the washing solution for one second to two hours.
5. The process according to claim 1 , wherein the halide complex is in liquid form before contacting the surface of the resin film.