Process for forming a patterned thin film structure for in-mold decoration
A process for forming a patterned thin film structure on a substrate or in-mold decoration film is disclosed. A pattern is printed with a material, such as a masking coating or ink, on the substrate, the pattern being such that, in one embodiment, the desired structures will be formed in the areas where the printed material is not present, i.e., a negative image of thin film structure to be formed is printed. In another embodiment, the pattern is printed with a material that is difficult to strip from the substrate, and the desired thin film structures will be formed in the areas where the printed material is present, i.e., a positive image of the thin film structure is printed. The thin film material is deposited on the patterned substrate, and the undesired area is stripped, leaving behind the patterned thin film structure.
1. A process for forming a patterned thin film structure on a substrate, comprising:
printing on the substrate with a first material a pattern defining a positive image of a decorative design to be formed on the substrate such that the first material is printed in the area where the thin film structure is to be formed, the first material being strippable using a first solvent;
overcoating the printed surface of the substrate with a second material that is not strippable using the first solvent;
stripping the first material away using the first solvent in a process that strips away the first material and the second material formed on the first material without stripping away the second material formed directly on the substrate, such that the second material remains coated on the substrate where the first material was not present, thereby defining a negative image of the decorative design to be formed on the substrate such that the second material remains in the area where the thin film structure is not to be formed;
depositing a thin film material on the patterned substrate; and
stripping to remove the second material and the thin film material deposited on the second material to form the thin film structure in the shape of the decorative design;
wherein the substrate and the patterned thin film structure formed thereon are suitable for use as an IMD decorated film.
2. The process for forming a patterned thin film structure on a substrate as recited in claim 1 , wherein the first material repels the second material such that the second material fills in the areas of the substrate where the first material has not been printed without coating the areas where the first material is present.
3. The process for forming a patterned thin film structure on a substrate as recited in claim 1 , wherein the first solvent is an aqueous solution or water.
4. The process for forming a patterned thin film structure on a substrate as recited in claim 1 , wherein the first solvent is a non-aqueous solvent or solution.
5. The process for forming a patterned thin film structure on a substrate as recited in claim 1 , wherein the first solvent is an aqueous basic solution, and the step of stripping the second material comprises using a second solvent comprising an aqueous acidic solution, an aqueous neutral solution, or water.
6. The process for forming a patterned thin film structure on a substrate as recited in claim 1 , wherein the first solvent is an aqueous acidic solution and the step of stripping the second material comprises using a second solvent comprising an aqueous basic solution, an aqueous neutral solution, or water.
7. The process for forming a patterned thin film structure on a substrate as recited in claim 1 , wherein the first solvent is an aqueous neutral solution or water and the step of stripping the second material comprises using a second solvent comprising an aqueous acidic solution or an aqueous basic solution.