A decorative film is comprised of a surface film, such as vinyl chloride, on which an adhesive layer is applied or laminated and, in some cases, said adhesive layer is protected by a release film. In the case of possessing a release film, this decorative film is used by applying it on the surface of an adherent (article to be decorated) after removing the release film.
In this case, since the adherend is comprised of a resin having a strong plasticizer migration ability, such as a vinyl chloride resin, when the surface film is a film having a low plasticizer resistance, such as a vinyl chloride sheet, the plasticizer is migrated from the adherent to the surface film, generating wrinkles on the surface sheet and, thereby resulting in the impairment of its decorative characteristics and weathering characteristics. For this reason, a means is required to prevent the deterioration of the surface film due to the migration of the plasticizer from the adherent.
Japanese Unexamined Patent Publication (Kokai) No. 59-5944 discloses a decorative film which prevents the migration of a plasticizer from an adherent to the film by placing a barrier layer comprising a urethane resin between a vinyl chloride surface film and an adhesive layer. In such an aspect, however, the production cost become unduly expensive because of the addition of the barrier layer. Japanese Unexamined Patent Publication (Kokai) No. 3-45671 discloses a decorative film which utilizes a surface film having improved plasticizer resistance due to the content of a urethane resin, and an adhesive containing a plasticizer resistant monomer, such as vinyl acetate. However, the cost of this decorative film tends to be expensive due to the use of the surface film containing a urethane resin.
USPTO Backgrounds
USPTO Backgrounds