JP4307241B2 - Decorative sheet with protective sheet and method for producing decorative molded product - Google Patents

Description

  The present invention relates to a decorative sheet with a protective sheet and a method for producing a decorative molded product using the decorative sheet.

  As a prior known document, a laminated film for imparting wear resistance and chemical resistance to the surface of a three-dimensional insert molded article having a deep drawing and a deep drawing provided with wear resistance and chemical resistance on the surface. There exists patent document 1 called the manufacturing method of a three-dimensional-shaped insert molded article. The laminated film of the present invention comprises a heat-resistant release film, a transfer layer made of a specific material formed on the release surface of the release film, and a shapeable film. A surface protective layer containing an uncured resin component rich in flexibility is formed on the surface of the transfer layer in contact with the release surface.

  The method for producing a deep-drawn three-dimensional insert molded product imparted with wear resistance and chemical resistance from the laminated film is obtained by peeling and removing the release film from the laminated film, and the remaining transfer layer. The insert film consisting of a moldable film is inserted into the molding die so that the molding die surface and the surface protective layer are in contact with each other, and after insert molding, the active energy ray is applied to the surface protective layer of the insert molded product. The surface protective layer is cured by irradiating and imparts wear resistance and chemical resistance.

JP2000-079796

  However, when insert molding is repeated by the above method, since the surface protective layer is exposed to the state where the molding die surface is always touched, the uncured resin component contained in the surface protective layer is gradually applied to the molding die surface. There is a problem that the smoothness of the molding die surface is lost due to adhesion and deposition on the surface, and the uneven shape of the deposit is transferred to the surface of the insert molded product, and the molding die surface must be frequently cleaned. was there. Further, the surface protective layer containing an uncured resin component is very easily damaged, and there is a problem that it is difficult to handle in the molding process.

  Therefore, in order to solve the above problems, the present inventor has a methacryl equivalent weight of 100 to 300 g / eq, a hydroxyl value of 20 to 500, and a weight average molecular weight of 5000 to 50000 on the shaped sheet on which the decorative layer is formed. A surface protective layer having a thickness of 3 to 70 μm made of a heat or active energy ray-curable resin composition containing the polymer and polyfunctional isocyanate as active ingredients is formed, and a protective layer having a thickness of 20 to 200 μm is formed on the surface protective layer. Invented a decorative sheet with a protective sheet to which the sheet was attached.

  That is, the present invention selects a specific material and a surface protective layer having a specific film thickness, and provides a protection for obtaining a three-dimensionally shaped insert molded product with a deep drawing having a high surface hardness provided with a protective film having a specific film thickness. Since it is a decorative sheet with a sheet and the uncured resin component of the surface protective layer does not adhere to the molding die surface, the trouble of frequently cleaning the molding die surface is eliminated. Moreover, since the protective sheet prevents the surface protective layer from being scratched, it is easy to handle.

  Further, the present invention may be a decorative sheet with a protective sheet, in which the protective sheet is a protective sheet in which an adhesive layer mainly composed of ethylene vinyl alcohol resin is formed on a polyethylene sheet. Further, the present invention may be a decorative sheet with a protective sheet, wherein the formable sheet is a formable sheet having a pencil hardness of F or more and a thickness of 50 to 300 μm.

  In addition, the present invention inserts a decorative sheet with a protective sheet into an injection mold, injects a molding resin into the injection mold to obtain a decorative molded product, peels off the protective sheet, and decorates It is a method for producing a decorative molded article, wherein the surface protective layer on the surface of the molded article is irradiated with active energy rays to cure the surface protective layer.

  Therefore, the decorative sheet with a protective sheet of the present invention does not have the trouble of frequently cleaning the molding die surface without the uncured resin component of the surface protective layer adhering to the molding die surface. effective. Further, since the protective sheet prevents the surface protective layer from being scratched, it is easy to handle and there is an effect that a desired decorative molded product having a high surface hardness can be easily obtained.

  Hereinafter, it will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view showing an embodiment of a decorative sheet with a protective sheet of the present invention. FIG. 2: is sectional drawing which shows one Example of the decorative molded product obtained by the decorating sheet with a protection sheet of this invention.

  The protective sheet has a structure in which a pressure-sensitive adhesive layer that does not adhere to or react with the surface protective layer is formed on a sheet base material having a deep drawability similar to that of the shapeable sheet, even after a molding process requiring high temperature and pressure. Consists of. However, the adhesive layer may be omitted when the sheet base material itself has appropriate adhesiveness.

  As a material of the sheet base material of the protective sheet, a single layer film selected from resins such as polyethylene, polypropylene, urethane, ethylene vinyl acetate, and ethylene vinyl alcohol, or lamination of two or more resins selected from the above There is a film or a copolymer film. The thickness of the sheet base material of the protective sheet is preferably 10 to 180 μm. If it is thinner than 10 μm, wrinkles are likely to occur, and if it is thicker than 180 μm, it is difficult to handle.

  Examples of the material for the adhesive layer of the protective sheet include resins such as ethylene vinyl alcohol, polyester, acrylic, and urethane. The thickness of the adhesive layer is preferably 5 to 100 μm. If the thickness is less than 30 μm, the tackiness may be insufficient. If the thickness is more than 100 μm, the residual solvent contained in the adhesive layer may attack the surface protective layer and the like.

  The thickness of the entire protective sheet is preferably 20 to 200 μm. If the thickness is less than 20 μm, the protective sheet may be broken during the molding process. If the thickness is greater than 200 μm, the protective sheet may be deformed or a hole may be formed due to the heat and pressure of the injection molding resin. .

  Among these, a protective sheet having a polyethylene sheet as a base material and an ethylene vinyl alcohol resin as an adhesive layer is preferable. This is because it has excellent adhesiveness and cushioning properties compared to other products, and it is easy to handle and a decorative molded product can be easily obtained.

  The surface protective layer is made of a heat and active energy ray curable resin composition. The heat and active energy ray-curable resin composition is a resin composition containing a polymer and a polyfunctional isocyanate as active ingredients. In particular, the heat and active energy ray-curable resin composition having a methacryl equivalent of 100 to 300 g / eq, a hydroxyl value of 20 to 500, and a weight average molecular weight of 5,000 to 50,000 is deeply drawn with sufficient flexibility when uncured. It is possible to form a hard coat film with excellent wear resistance after curing.

  The thickness of the surface protective layer is preferably 3 to 70 μm. If the thickness is less than 3 μm, desired wear resistance, scratch resistance and the like cannot be obtained, and if the thickness exceeds 70 μm, drying becomes difficult and productivity is greatly reduced. Furthermore, between 40 and 70 μm, even if the thickness is increased, the wear resistance, scratch resistance and the like are hardly changed. Therefore, it is more preferable to make the thickness of the surface protective layer 3 to 40 μm from the viewpoint of improving productivity. preferable.

  The reason for forming the surface protective layer is to improve the wear resistance, scratch resistance, etc. of the surface. Even if the hardness is increased only with the formable sheet, the wear resistance is limited to about 2H. This is because the scratch resistance and the like are inferior to those of conventional hard coat films.

  The formable sheet is required to have a certain level of hardness, sufficient deep drawability, and other functions as a base material.

  The shapeable sheet preferably has a pencil hardness F or higher in the measuring method of JIS-K-5400. The reason why the pencil hardness is F or higher is that the harder the surface protective layer is formed, the harder the surface protective layer is formed. This is because a decorative molded product having a pencil hardness of 2H to 8H can be obtained.

  The thickness of the shapeable sheet is preferably 10 to 2000 μm. If the thickness is less than 10, there is no rigidity and it is difficult to provide a surface protective layer or the like, and if the thickness exceeds 2000 μm, it takes time for deep drawing and the productivity is lowered.

  As the formable sheet, a single layer sheet selected from resins such as polycarbonate, polyamide, polyimide, polyester, acrylic, olefin, urethane, acrylonitrile butadiene styrene, or lamination of two or more kinds of resins selected from the above. Although a sheet | seat or a copolymer sheet is mentioned, an acrylic sheet is the most preferable from points, such as light resistance.

  The acrylic sheet is made of a hard acrylic resin such as methacrylic acid ester or acrylic acid ester and soft acrylic rubber. The ratio is in the range of 60:40 to 90:10 by weight%, and the higher the ratio of the hard acrylic resin, the higher the hardness and the more preferable tendency. However, when the ratio exceeds 90:10 by weight%, it becomes difficult to form a sheet.

  Moreover, as an example of the formable sheet by laminating two or more kinds of resin sheets, there is a sheet in which an acrylic sheet and an acrylonitrile butadiene styrene sheet are laminated. These lamination methods include thermal lamination and dry lamination.

  The decoration layer is a printing layer for expressing a pattern to be decorated, such as a wood grain pattern, a stone pattern, a cloth pattern, characters, a geometric pattern, and a solid surface. A plurality of decorative layers may be formed in parallel. Moreover, a decoration layer may be provided in the surface protective layer formation surface side of a shapeable sheet, and may be provided in the other side.

  Examples of the material of the decorative layer 2 include acrylic, vinyl chloride fat, nitrified cotton, urethane, chlorinated rubber, acrylic-vinyl acetate copolymer, acrylic-vinyl chloride, acrylic-urethane resin, and the like. Not.

  The decorative layer may be provided with a metal film layer such as aluminum, chromium, copper, nickel, indium, tin, or silicon oxide by a method such as vacuum deposition or plating. In this case, the metal film layer may be entirely or patterned. Further, a pearl tone, a metallic tone, a metallic luster tone, or the like may be used by using an ink or a paint containing a glitter pigment.

  The thickness of the decorative layer is preferably 0.5 μm to 50 μm. If the thickness is less than 0.5 μm, there is a problem that sufficient designability cannot be obtained, and if it is thicker than 50 μm, there is a problem that it is difficult to dry after printing. However, in the case of a metal film layer, 50 to 1200 mm is preferable. This is because if the thickness of the metal film layer is less than 50 mm, there is a problem that sufficient metallic luster cannot be obtained, and if it is more than 1200 mm, there is a problem that cracks are likely to occur.

  Examples of the method for providing the decorative layer include printing methods such as gravure printing, screen printing, and offset printing, various coating methods, metal thin film forming methods such as vapor deposition, ion plating, and sputtering.

  Moreover, you may form an adhesive layer in the surface on the opposite side to the surface protective layer of a shapeable sheet as needed. Examples of the material of the adhesive layer include resins such as acrylic, vinyl chloride, urethane, polyester, polypropylene, polyethylene, polystyrene, polycarbonate fat, vinylon, acetate, polyamide, and the like, which is preferable according to the adhesion to the adherend. Select material. In particular, an adhesive layer made of vinyl chloride, vinyl acetate, and an acrylic resin has a wide application range of adherends that can be bonded, and is useful.

  The thickness of the adhesive layer is preferably 0.5 μm to 50 μm. If the film thickness is less than 0.5 μm, there is a problem that sufficient adhesion cannot be obtained, and if it is more than 50 μm, there is a problem that it is difficult to dry after printing. As a method for forming the adhesive layer, there are a gravure printing method, an offset printing method, a screen printing method, and a method such as painting, dipping, and reverse coater.

  Further, when the adhesion between the layers is poor, an anchor layer may be provided as necessary. Examples of the material of the anchor layer include resins such as acrylic, vinyl chloride, urethane, polyester, polypropylene, polyethylene, polystyrene, polycarbonate, vinylon, acetate, polyamide, and the like, and a preferable material is appropriately selected according to the adhesion with each layer. To do.

  The thickness of the anchor layer is preferably 0.5 μm to 50 μm. When the film thickness is less than 0.5 μm, there is a problem that sufficient adhesion cannot be obtained, and when it is more than 50 μm, there is a problem that it is difficult to dry after printing. The formation method of the anchor layer 5 includes methods such as painting, dipping, and reverse coater in addition to methods such as gravure printing, offset printing, and screen printing.

  If the obtained decorative sheet with a protective sheet is inserted into an injection mold and a molding resin is injected into the injection mold, a decorative molded product is obtained. After that, after peeling off the protective sheet, the surface protective layer on the surface of the decorative molded product is irradiated with active energy rays to cure the surface protective layer, or the surface protective layer on the surface of the decorative molded product is irradiated with active energy rays. Then, after the surface protective layer is cured, the protective sheet is peeled off. By any one of these methods, a decorative molded product having a desired high surface hardness can be obtained.

  The irradiation amount of the active energy ray varies depending on the material and thickness of the surface protective layer, but is preferably in the range of 50 to 1000 mW / square centimeter. This is because if the integrated light quantity is less than 50 mW / square centimeter, the function of the surface protective layer cannot be obtained due to insufficient curing, and if the integrated light quantity exceeds 1000 mW / square centimeter, the productivity decreases.

  Examples of the molding resin include resins such as polypropylene, polyethylene, polystyrene, acrylonitrile butadiene styrene, polycarbonate, acrylic, urethane, polyester, acetate, and polyamide.

  Before inserting the decorative sheet with a protective sheet into the injection mold, the decorative sheet with the protective sheet is processed into a desired deep-drawn three-dimensional shape by a method such as vacuum forming, pressure forming, or press forming. Alternatively, the decorative sheet with a protective sheet may be cut into a desired shape by a method such as Thomson punching, die press, or router processing.

  On an acrylic sheet having a thickness of 200 μm and a pencil hardness of H, a decorative layer made of acrylic-vinyl chloride resin and an anchor layer made of urethane resin were formed by gravure printing to a thickness of 3 μm, respectively, and a methacryl equivalent amount of 250 g / eq, A surface protective layer made of a heat or active energy ray-curable resin composition containing a polymer having a hydroxyl value of 400 and a weight average molecular weight of 40000 and a polyfunctional isocyanate as active ingredients is applied by a reverse coating method to a thickness of 40 μm, and a decorative sheet Got.

  Next, a protective sheet in which an adhesive layer having a thickness of 40 μm made of ethylene vinyl alcohol resin is formed on a polyethylene sheet having a thickness of 100 μm is prepared. The protective sheet is attached to the surface protective layer surface of the decorative sheet by a coextrusion laminating method. A decorative sheet was obtained.

  This decorative sheet with a protective sheet is processed into a deep-drawn three-dimensional shape by a compressed air molding method, cut into the desired shape, and then placed so that the protective sheet is in contact with the surface of the injection mold and injection molded with a polycarbonate resin. did. When the surface protection layer surface of the obtained decorative molded product was irradiated with ultraviolet rays having an integrated light amount of 300 mW / square centimeter and the protective sheet was peeled off, a desired decorative molded product with a pencil hardness of 3H was obtained.

  Heat or activity containing, as main components, a polymer having a methacrylic equivalent of 150 g / eq, a hydroxyl value of 120, and a weight average molecular weight of 8,000 on a biaxially stretched polyethylene terephthalate film having a release treatment of 25 μm in thickness. A surface protective layer made of an energy ray-curable resin composition is applied by a lip coating method to a thickness of 20 μm, and an anchor layer made of a urethane resin, a decorative layer made of an acrylic-vinyl chloride resin, and a vinyl chloride resin A transfer sheet was prepared in which each of the adhesive layers was formed by gravure printing to a thickness of 4 μm.

  This transfer sheet was thermally transferred in advance to a shapeable sheet in which an acrylic sheet having a thickness of 50 μm and pencil hardness F and an acrylonitrile butadiene styrene sheet having a thickness of 200 μm were laminated, and the biaxially stretched polyethylene terephthalate film was peeled off. On the other hand, a protective sheet in which an adhesive layer of 40 μm thickness made of ethylene vinyl alcohol resin is formed on a 20 μm thick polyethylene sheet is prepared and applied to the surface protective layer surface after peeling of the biaxially stretched polyethylene terephthalate film by a coextrusion laminating method. A decorative sheet with a protective sheet was used.

  This decorative sheet with protective sheet is processed into a deep-drawn three-dimensional shape by a vacuum forming method, cut into a desired shape, and then placed so that the protective sheet is in contact with the surface of the injection mold. Polycarbonate / acrylonitrile butadiene styrene Insert-molded with resin. When the protective sheet was peeled off from the obtained decorative molded product and irradiated with ultraviolet rays with an integrated light amount of 200 mW / square centimeter, a desired decorative molded product with a pencil hardness of 2H was obtained.

  The decorative sheet obtained by the present invention is used for decorating molded products used for home appliances, housing equipment, office equipment, automobile parts, and the like.

It is sectional drawing which shows one Example of the decorating sheet with a protection sheet which concerns on this invention. It is sectional drawing which shows one Example of the decorative molded product obtained by the decorating sheet with a protection sheet which concerns on this invention.

Explanation of symbols

A decoration sheet
1 Protection sheet
2 Surface protective layer
3 decoration layers
4 Shapeable sheet
5 Molding resin

Claims (1)

Shapeable sheet, decorative layer formed on the shapeable sheet, and methacryl equivalent weight of 100 to 300 g / eq, hydroxyl value of 20 to 500, and weight average molecular weight of 5000 formed on the decorative layer. A surface protective layer having a thickness of 3 to 70 μm composed of a thermal and active energy ray-curable resin composition containing ˜50000 polymer and polyfunctional isocyanate as active ingredients, and a thickness of 20 attached to the surface protective layer. It is a manufacturing method of the decorative molded product using the decorative sheet with a protective sheet which has -200 micrometers and the protective sheet in which the adhesion layer which has an ethylene vinyl alcohol resin as a main component was formed on the polyethylene sheet,
Processing the decorative sheet with a protective sheet into a desired deep-drawn three-dimensional shape;
The processed decorative sheet with a protective sheet is inserted into an injection mold, and a molding resin is injected into the injection mold to obtain a decorative molded product integrated with the decorative sheet with a protective sheet. Process,
The protective sheet is peeled off and the surface protective layer of the obtained decorative molded product is irradiated with an active energy ray to cure the surface protective layer, or the surface protective layer of the obtained decorative molded product. A method for producing a decorative molded product, comprising: irradiating an active energy ray to cure the surface protective layer and peeling the protective sheet.

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