Insert mold decorating film for thermoplastic resin and methods for making
View Patent ↗A multi-layer printable thermoplastic film consisting of at least a fluoride polymer film having laminated thereto a polycarbonate film. The printable film is preformed (vacuum molding or thermoforming) and then inserted into a mold which has the configuration of the preformed printable film. A base layer of a thermoplastic such as a polycarbonate resin is injection molded to the exposed surface of the preformed printable film. The molded structure has exterior automotive applications such as lens, etc.
1. A process for forming a molded structure which process comprises forming a thermoplastic printable film comprising a fluoride polymer by laminating an extruded polycarbonate film to the fluoride polymer under heat and pressure, wherein, during the laminating, surfaces of the extruded polycarbonate film vitrify and an interior portion of the polycarbonate film remains in a thermoplastic or molten state, preforming the printable film to a predetermined configuration, placing the preformed printable film in a mold in which the inner surface of the mold conforms to the configuration of the preformed printable film and the fluoride polymer film is in contact with the inner surface of the mold; and molding by injection molding a thermoplastic base layer to an exposed side of the printable preformed film.
2. The process of claim 1 wherein the injection molding base layer is a polycarbonate resin.
3. The process of claim 1 wherein the process further comprises forming a printable film comprised of a removable polyester film, an intermediate film of the fluoride polymer and the polycarbonate layer laminated to the fluoride polymer and then removing the polyester film.
4. The process of claim 1 wherein the polyester film is removed prior to preforming the printable film.
5. The process of claim 1 , wherein the thermoplastic printable film has a percent haze of less than 2.5 percent and a birefringence of less than 25 nanometers.
6. A process for forming a molded structure comprising the steps of:
extruding a thermoplastic polycarbonate resin to form an thermoplastic polycarbonate film;
laminating the thermoplastic polycarbonate film to a fluoride polymer under heat and pressure to form a printable film, wherein, during the laminating, a temperature of any calendering rolls is controlled to a temperature that is below a glass transition temperature of the thermoplastic polycarbonate film and is effective to vitrify surfaces of the thermoplastic polycarbonate film while an interior portion of the polycarbonate film remains in a thermoplastic or molten state;
cooling the printable film at a rate effective to have a percent haze of less than 2.5 percent and a birefringence of less than 25 nanometers;
preforming the printable film to a predetermined configuration;
placing the preformed printable film in a mold in which an inner surface of the mold conforms to a configuration of the preformed printable film and the fluoride polymer film is in contact with the inner surface of the mold; and
injection molding a thermoplastic base layer to an exposed side of the preformed printable film.
7. The process of claim 6 , wherein the injection molding base layer is a polycarbonate resin.
8. The process of claim 6 , the process further comprises forming a printable film comprised of a removable polyester film, an intermediate film of the fluoride polymer, and the polycarbonate layer laminated to the fluoride polymer, and then removing the polyester film.
9. The process of claim 6 , wherein the polyester film is removed prior to preforming the printable film.
10. A process for forming a molded structure comprising:
extruding a thermoplastic polycarbonate resin to form an thermoplastic polycarbonate film;
laminating the thermoplastic polycarbonate film to a fluoride polymer under heat and pressure to form a printable film;
cooling the printable film at a rate effective to have a percent haze of less than 2.5 percent and a birefringence of less than 25 nanometers;
preforming the printable film to a predetermined configuration;
placing the preformed printable film in a mold in which an inner surface of the mold conforms to a configuration of the preformed printable film and the fluoride polymer film is in contact with the inner surface of the mold; and
molding by injection molding a thermoplastic base layer to an exposed side of the preformed printable film.