JP3637298B2 - Decorative sheet, decorative molded product and its manufacturing method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a decorative molded product used for an interior part or exterior part of an automobile, a panel of an electrical appliance, a manufacturing method thereof, and a decorative sheet used for the manufacturing method.
[0002]
[Prior art]
Conventionally, a decorative sheet having a metal thin film layer is one in which a decorative layer composed of a metal thin film layer or the like is formed on a base sheet, and after the decorative layer adheres to a molded product, the base sheet is peeled off. There are a type to be used and a type to be used without peeling off the base sheet. As a method for obtaining a decorative molded product having a metallic luster and brightness having the metal thin film layer, there is a method in which the decorative sheet having the metal thin film layer is integrated with the molded product.
[0003]
[Problems to be solved by the invention]
There were many pinholes in the metal thin film layer of the decorative sheet. When pinholes are generated, there is a problem that the gloss and brightness of the decorative molded product in which the decorative sheet is integrated with the molded product are deteriorated, resulting in poor appearance and a decrease in the yield rate. The cause of the pinhole is in the process of manufacturing the decorative sheet. For example, the metal thin film layer is scratched when the sheet is carried, or the metal thin film layer is corroded due to adhesion of a solvent or the like.
[0004]
[Means for Solving the Problems]
In the decorative sheet of this invention, a decorative layer is formed on a base sheet, and the decorative layer contains at least 10 to 50% by weight of a pearl pigment composed of a metal thin film layer and bismuth oxychloride from the base sheet side. A hole concealing layer is included.
In this decorative sheet, the decorative layer may include a pinhole concealing layer containing 10 to 50% by weight of a pearl pigment composed of a surface protective layer, a metal thin film layer, and bismuth oxychloride from the base sheet side. Good.
The particle size of the pearl pigment made of bismuth oxychloride may be 5 to 25 μm.
Further, the decorative layer may have a colored layer having a total light transmittance of 30 to 99% on the side opposite to the metal thin film layer of the pinhole concealing layer.
The decorative molded product of this invention has a decorative layer integrated on the molded product, and the decorative layer contains at least 10 to 50% by weight of a pearl pigment composed of bismuth oxychloride from the molded product side. And a metal thin film layer .
In this molded product, the decorative layer may include a pinhole concealing layer, a metal thin film layer, and a surface protective layer containing 10 to 50% by weight of a pearl pigment made of bismuth oxychloride from the molded product side .
The particle size of the pearl pigment made of bismuth oxychloride may be 5 to 25 μm.
Moreover, the decoration layer may have a colored layer having a total light transmittance of 30 to 99% on the side opposite to the metal thin film layer of the pinhole concealing layer.
The method for producing a decorative molded product according to the present invention includes: transforming the decorative sheet according to any of the above to a three-dimensional shape, placing the decorative sheet in an injection mold, closing the mold, and cooling the molded resin after being injected into the cavity The mold is opened to obtain a decorative molded product in which the decorative sheet and the molded resin are integrated.
The method for producing a decorative molded product according to the present invention includes placing the decorative sheet described in an injection mold, closing the mold, injecting a molding resin into the cavity, cooling the mold, and then opening the mold. Stripping to obtain a decorative molded product in which the decorative layer and the molded resin are integrated.
[0005]
DETAILED DESCRIPTION OF THE INVENTION
The decorative sheet of the present invention will be described (see FIG. 1).
In the decorative sheet of this invention, a decorative layer is formed on a base sheet, and the decorative layer contains at least 10 to 50% by weight of a pearl pigment composed of a metal thin film layer and bismuth oxychloride from the base sheet side. A hole concealing layer is included. The decorative sheet includes a type that is used by peeling the base sheet after the decorative layer is bonded to the molded product, and a type that is used without peeling the base sheet.
[0006]
As the base sheet 1, a sheet made of a thermoplastic resin or a thermosetting resin can be used. Examples of the material of the base sheet 1 include polycarbonate resin, polyamide resin, polyimide resin, polyester resin, acrylic resin, olefin resin, and urethane resin. The base sheet 1 may be a sheet composed of a single layer, or may be a laminated sheet obtained by selecting a plurality of materials from the above materials, producing sheets with different types of resins, and bonding them together. Alternatively, a sheet obtained by selecting a plurality of the above materials and copolymerizing different types of resins may be used.
[0007]
The thickness of the base sheet 1 can be 15 to 250 μm. When the thickness is less than 15 μm, film formation tends to be difficult, and it may be difficult to follow elongation when deformed into a three-dimensional shape, and may be easily broken. On the other hand, if it exceeds 250 μm, it may take a long time to obtain an optimal softened state for deforming the decorative sheet into a three-dimensional shape, so that the production efficiency may deteriorate. Moreover, even if it considers the role as a surface protective layer of a decorative molded product, the thickness beyond it may be unnecessary and it may lead to a cost increase.
[0008]
In the case where the base sheet 1 is peeled and used, the decorative layer is a pinhole concealing layer containing 10 to 50% by weight of a pearl pigment composed of a surface protective layer, a metal thin film layer, and bismuth oxychloride from the base sheet side. Can be included.
The purpose of forming the surface protective layer is to prevent the metal thin film layer 2 from being scratched or deteriorated by light. The material of the surface protective layer can be formed of any one of a thermoplastic resin, a thermosetting resin, and an ionizing radiation curable resin. As a method for forming the surface protective layer, a general film forming method such as gravure printing or roll coating can be used. The thickness of the surface protective layer is preferably 1 to 15 μm. When the thickness is less than 1 μm, the scratch resistance and light resistance of the metal thin film layer 2 are lowered, and the function as the surface protective layer may be weakened. If it exceeds 15 μm, it may be difficult to apply a film forming method such as the printing method or the roll coating method. In addition, since the solvent content increases, drying may become difficult and production efficiency may decrease, or blocking may easily occur. Moreover, in order to improve the peelability between the base sheet 1 and the surface protective layer, the base sheet 1 may be subjected to a mold release treatment using a melamine resin or the like by a gravure coating method or the like.
[0009]
The metal thin film layer 2 is a layer for applying metallic luster and brightness to the molded product 6. Examples of the material of the metal thin film layer 2 include aluminum, chromium, indium, tin, nickel, gold, silver, copper, platinum alone, a mixture thereof, or an alloy. Examples of the method for forming the metal thin film layer 2 include a vacuum deposition method and a sputtering method. The film thickness of the metal thin film layer 2 can be 100 to 400 mm. If the film thickness is less than 100 mm, the film thickness management in the vapor deposition process may be difficult. If it exceeds 400 mm, it tends to oxidize and may lose color due to corrosion.
[0010]
The metal thin film layer 2 can be formed entirely or partially. In order to form a part, there are a so-called paster method and a celite method. The paster method is a method in which a metal thin film other than the masked portion is dissolved and removed with an alkali by vapor deposition on the entire surface and masking in a pattern with an alkali-insoluble ink. With the celite method, an anchor layer is formed, masked in a pattern with water-soluble ink, deposited on the entire surface, washed with water, and dissolved and removed to dissolve the water-soluble ink. It is a method through a process of removing only a portion of the metal thin film. There is also a so-called laser marking method. In this method, a light shielding layer is formed on the entire surface of the metal thin film layer 2 and then the laminated portion of the metal thin film layer 2 and the light shielding layer is removed into a desired pattern shape by a laser beam.
[0011]
The pinhole concealing layer 3 is a layer containing 10 to 50% by weight of a pearl pigment made of bismuth oxychloride (BiClO).
Since the surface of the pearl pigment made of “bismuth oxychloride” has a smooth surface, the surface of the pinhole concealing layer 3 does not become rugged irregularities due to the pigment particles. Further, “bismuth-based” pearl pigments have so-called silky gloss and brightness. For this reason, the degree of gloss and brightness due to the pinhole concealing layer 3 is close to the level of gloss and brightness of the metal thin film layer 2, so that pinholes in the metal thin film layer are less noticeable.
The reason why the layer containing 10 to 50% by weight of the pearl pigment is used is that when the content of the pearl pigment is less than 10% by weight, a metal vapor deposition layer having a gloss or brightness close to that cannot be obtained. On the other hand, when the content of the pearl pigment exceeds 50% by weight, peeling of the pinhole concealing layer 3 is likely to occur. Specifically, it is formed by using an ink obtained by dissolving the pearl pigment in a solvent together with a resin binder. At this time, the weight percent of the resin binder and the pearl pigment can be in the following range. Resin binder: Pearl pigment = 50 to 90:50 to 10 (Note that 100 is obtained by mixing the resin binder and the pearl pigment).
[0012]
In the case of obtaining a film closer to the gloss and brightness of the metal thin film layer 2, it can further contain a coloring pigment such as a carbon black pigment. The weight% may be selected as appropriate while adjusting the color tone, but can be in the following range. (Resin binder + pearl pigment): Colored pigment = 100: 5-10.
[0013]
The particle size of the pearl pigment made of bismuth oxychloride can be 5 to 25 μm. When the particle size is less than 5 μm, the luster and brightness of the pinhole concealing layer 3 are insufficient, and the effect of concealing pinholes generated in the metal thin film layer 2 tends to be lowered. Moreover, when the particle size exceeds 25 μm, when a decorative molded product in which the decorative sheet and the molding resin are integrated is obtained, the surface becomes uneven along the outer shape of the particles of the pearl pigment, and the gloss and brightness are likely to be lowered. Become.
[0014]
The pinhole concealing layer 3 can be formed entirely or partially within a thickness range of 3 to 30 μm. When the film thickness is less than 3 μm, there are cases where the gloss and brightness of the metal thin film layer 2 due to pinholes cannot be sufficiently prevented. When the film thickness exceeds 30 μm, the flexibility of the pinhole shielding layer is lowered, so that it becomes difficult to bend sufficiently at the corner portion having a small radius of curvature when the decorative sheet is deformed into a three-dimensional shape. Further, since the absolute amount of the solvent increases, the adhesiveness remains in the pinhole concealing layer 3 due to heat when deformed into a three-dimensional shape, making it difficult to remove from the mold when deforming into a three-dimensional shape. Moreover, the drying process of the pinhole concealing layer 3 takes a long time.
[0015]
The pinhole concealing layer 3 can be formed by a normal printing method. When the metal thin film layer 2 is colored, the pinhole concealing layer 3 can also be colored by containing color pigments of the same color, tone and brightness. The pinhole concealing layer 3 can also be used as a mask when the metal thin film layer 2 is partially formed by the paster method.
[0016]
The decorative layer can have a colored layer 4 having a total light transmittance of 30 to 99% on the pinhole concealing layer 3 (see FIG. 1). The colored layer 4 is a layer for assisting color development of the pinhole concealing layer 3. If the total light transmittance is less than 30%, the gloss and brightness of the pinhole concealing layer 3 may be lowered, and the pinhole concealing effect may be impaired. If it exceeds 99%, it is difficult to obtain a sufficient color assisting effect. In order to obtain the total light transmittance in the above range, the thickness of the colored layer 4 can be set to 1 to 30 μm. In order to improve interlayer adhesion, a transparent layer can be formed between the pinhole concealing layer 3 and the colored layer 4. If a vinyl chloride vinyl acetate copolymer resin, an acrylic resin, or the like is selected as the material of the resin binder constituting the colored layer 4, it can be adhered to the molded product 6 without the adhesive layer 5 described later.
[0017]
The adhesive layer 5 can be formed as necessary in order to adhere the decorative sheet to the molded product 6. The adhesive layer 5 can be transparent, colored translucent, and opaque. The film thickness of the adhesive layer 5 can be 1 to 500 μm. When the film thickness is less than 1 μm, sufficient adhesion cannot be obtained between the adhesive layer 5 and the molding resin. When the film thickness exceeds 500 μm, the flexibility of the adhesive layer 5 is lowered, so that the decorative sheet is not easily bent at a portion having a small curvature radius when deformed into a three-dimensional shape. When the film thickness is relatively thick at 30 to 500 μm, sheets obtained by various film forming methods can be used. The ink used for forming the adhesive layer 5 can be appropriately selected according to the material of the molding resin to be integrated.
[0018]
The anchor layer can be formed as necessary so as to be in contact with the metal thin film layer 2 on the upper surface or the lower surface of the metal thin film layer 2. The purpose is to strengthen the adhesion between the metal thin film layer 2 and the layer in contact with it. Examples of the material for the anchor layer include thermoplastic resins such as vinyl chloride vinyl acetate copolymer resin, and thermosetting resins such as acrylic polyol.
[0019]
In the decorative molded product of the present invention, the pinhole concealing layer 3 side of the decorative sheet is integrated with the molded product 6. Examples of the molded product 6 include polycarbonate resin, acrylic resin, ABS resin, and AS resin (see FIG. 2).
[0020]
In the method for producing a decorative molded product according to the present invention, a decorative sheet deformed into a three-dimensional shape is placed in an injection mold, and after closing the mold, a molding resin is injected into the cavity, cooled, and then opened. Thus, a decorative molded product in which the decorative sheet and the molded resin are integrated is obtained.
As an example of the “three-dimensional shape”, it can be the same shape as the cavity of the injection mold. Specific applications include appliance buttons and mobile phone housings.
When the decorative sheet is a type to be used by peeling the base sheet 1, the mold is opened to peel off the base sheet 1, and a decorative molded product in which at least the surface protective layer, the decorative layer, and the molding resin are integrated is used. obtain.
[0021]
【Example】
(Example 1)
A thermosetting anchor layer made of an acrylic polyol resin is formed on a 125 μm-thick base sheet made of polycarbonate resin (“Iupilon” manufactured by Mitsubishi Plastics, Inc.) by gravure printing, and then aluminum is deposited on the entire surface to form a metal thin film. A layer was formed. Next, a urethane two-component curable ink containing 20% by weight of a pearl pigment made of bismuth oxychloride having an average particle size of 25 μm (“SG410 / special curing agent (resin binder: pearl pigment = 10: 1) manufactured by Seiko Advance Co., Ltd.) )) Was formed by a screen printing method so as to be a pinhole concealing layer having a thickness of 5 μm and subjected to hot air drying at 80 ° C. for 5 minutes. Next, an adhesive layer was formed by a screen printing method using an ink containing a vinyl chloride / vinyl acetate copolymer resin containing a carbon black pigment, and dried at 80 ° C. for 2 hours to form a decorative sheet. The adhesive layer also served as the reflective layer. A decorative sheet obtained by deforming this decorative sheet into a three-dimensional shape by a vacuum forming method was obtained. This decorative sheet is placed in an injection mold having a cavity shape corresponding to the three-dimensional shape of the decorative sheet, and a molding resin made of polycarbonate resin (“Toughlon” manufactured by Idemitsu Petrochemical Co., Ltd.) is injected and cooled. Solidified to obtain a decorative molded product in which the decorative sheet and the molded resin were integrated.
[0022]
(Comparative Example 1)
A decorative sheet and a decorative molded product were obtained in the same configuration as in Example 1 except that the content of the pearl pigment in the pinhole concealing layer of the decorative sheet was changed to 5% by weight.
A pinhole appearance inspection was performed using the above Example 1 and Comparative Example 1.
In Example 1, the gloss and brightness of the decorative molded product were hardly lowered even by pinholes generated in the metal thin film layer, and the yield rate was 90%. In Comparative Example 1, there were many cases where the gloss and brightness of the decorative molded product were lowered due to pinholes generated in the metal thin film layer, and the yield rate was 25%.
[0023]
(Example 2)
A surface protective layer made of an acrylic resin is formed on a 50 μm-thick base sheet made of a low-stretch PET film that has been subjected to a release treatment by a reverse coating method, and then a thermosetting anchor layer made of an acrylic polyol resin is gravure-coated. After forming by printing, aluminum is vapor-deposited on the entire surface to form a metal thin film layer, and urethane two-component curable ink containing 15% by weight of pearl pigment (“SG410 / special curing agent (resin binder: Pearl pigment = 10: 1) ”) was formed by screen printing so as to form a pinhole concealing layer having a film thickness of 5 μm, and hot air drying was performed at 80 ° C. for 5 minutes. Next, the adhesive layer was formed by the screen printing method using the ink which consists of vinyl chloride vinyl acetate copolymer resin, and the decorating sheet was obtained.
This decorative sheet is placed in an injection mold having a cavity shape corresponding to the three-dimensional shape of the decorative sheet, and a molding resin made of PMMA resin is injected and cooled and solidified. An integrated decorative molded product was obtained. After cooling this decorative molded product, the base sheet and the surface protective layer were peeled off simultaneously with mold opening.
[0024]
(Comparative Example 2)
A decorative sheet and a decorative molded product were obtained in the same configuration as in Example 2 except that the content of the pearl pigment in the pinhole concealing layer of the decorative sheet was 60% by weight.
A pinhole appearance inspection was performed using the above Example 2 and Comparative Example 2. In Example 2, the gloss and brightness of the decorative molded product were hardly lowered even by pinholes generated in the metal thin film layer, and the yield rate was 90%. In Comparative Example 1, many metal thin film layers were likely to be peeled from each other, and the yield rate was 20%.
[0025]
【The invention's effect】
In this invention, a decorative layer is formed on a base sheet, and the decorative layer includes a pinhole concealing layer containing at least 10 to 50% by weight of a pearl pigment composed of a metal thin film layer and bismuth oxychloride from the base sheet side. It is a decorating sheet characterized by including. Further, the decorative molded product of the present invention is such that at least the pinhole concealing layer side of the decorative layer composed of a pinhole concealing layer containing 10-50% by weight of a pearl pigment composed of a metal thin film layer and bismuth oxychloride is a molded product. It is characterized in that it is integrated. In addition, the method for producing a decorative molded product according to the present invention is a method in which a decorative sheet is transformed into a three-dimensional shape, placed in an injection mold, closed, and molded resin is injected into a cavity and cooled after being opened. Thus, a decorative molded product in which the decorative sheet and the molding resin are integrated is obtained.
Therefore, even if pinholes are generated in the metal thin film layer of the decorative sheet, the gloss and brightness of the decorative molded product do not decrease, so the appearance does not deteriorate and the yield rate does not decrease.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an example of a decorative sheet according to the present invention.
FIG. 2 is a cross-sectional view showing an example of a decorative molded product according to the present invention.
[Explanation of symbols]
1 Base sheet 2 Metal thin film layer 3 Pinhole concealing layer 4 Colored layer 5 Adhesive layer 6 Molded product 7 Pinhole

Claims (10)

  A decorative layer is formed on the base sheet, and the decorative layer includes a pinhole concealing layer containing at least 10 to 50% by weight of a pearl pigment composed of a metal thin film layer and bismuth oxychloride from the base sheet side. Characteristic decorative sheet.   The decorative sheet according to claim 1, wherein the decorative layer includes a pinhole concealing layer containing 10 to 50% by weight of a pearl pigment composed of a surface protective layer, a metal thin film layer, and bismuth oxychloride from the base sheet side.   The decorative sheet according to claim 1 or 2, wherein the particle size of the pearl pigment made of bismuth oxychloride is 5 to 25 µm. The decorative sheet according to any one of claims 1 to 3, wherein the decorative layer has a colored layer having a total light transmittance of 30 to 99% on the side opposite to the metal thin film layer of the pinhole concealing layer. The decorative layer is integrated on the molded product, and the decorative layer includes at least a pinhole concealing layer containing 10 to 50% by weight of a pearl pigment made of bismuth oxychloride from the molded product side, and a metal thin film layer. Decorative molded product characterized by The decorative molded product according to claim 5, wherein the decorative layer includes a pinhole concealing layer, a metal thin film layer, and a surface protective layer containing 10 to 50% by weight of a pearl pigment made of bismuth oxychloride from the molded product side .   The decorative molded product according to claim 5 or 6, wherein the particle size of the pearl pigment made of bismuth oxychloride is 5 to 25 µm. The decorative molded product according to any one of claims 5 to 7, wherein the decorative layer has a colored layer having a total light transmittance of 30 to 99% on the side opposite to the metal thin film layer of the pinhole concealing layer.   The decorative sheet according to any one of claims 1 to 4 is transformed into a three-dimensional shape, placed in an injection mold, closed, and molded resin is injected into a cavity and then cooled, and then the mold is opened. A method for producing a decorative molded product comprising obtaining a decorative molded product in which a decorative sheet and a molded resin are integrated.   The decorative sheet according to any one of claims 2 to 4 is placed in an injection mold, the mold is closed, the molding resin is injected into the cavity, cooled, the mold is opened, and the base sheet is peeled off. A method for producing a decorative molded product comprising obtaining a decorative molded product in which a decorative layer and a molded resin are integrated.

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