JP4964073B2 - Decorative sheet and its manufacturing method, decorative molded product - Google Patents

Description

  The present invention relates to a decorative sheet having a metallic luster and having both insulating properties and light shielding properties, a manufacturing method thereof, and a decorative molded product.

  In a communication device such as a mobile phone, an information device inside a car, a home appliance, and the like, there is a method in which a decorative sheet is used to decorate the surface of a plastic molded product in order to express a radio-transmitting metallic luster.

  There are an insert method and a transfer method as a method of decorating the surface of the transfer object. The insert method is a method of performing decoration by using a decorative sheet in which a metal thin film layer or the like is formed on a base sheet, and applying heat and pressure so that the decorative layer is in close contact with the object to be decorated. Further, when the object to be decorated is a resin molded product, there is a simultaneous molding insert method as a method for performing the insert method more rationally. The simultaneous molding method inserts a decorative sheet in a mold, injects and fills the resin in the mold, and cools to obtain a resin molded product. At the same time, the insert sheet is adhered to the surface of the molded product to decorate it. How to do it.

  The transfer method uses a transfer sheet in which a transfer layer composed of a release layer, a metal thin film layer, etc. is formed on a substrate sheet, and heat-presses the transfer layer to adhere to the transfer object, and then the substrate sheet is released. Thus, the decoration is performed by transferring only the transfer layer to the surface of the transfer object. In addition, when the material to be transferred is a resin molded product, there is a simultaneous molding transfer method as a method for performing the transfer method more rationally. The molding simultaneous transfer method is a method in which a transfer sheet is sandwiched in a molding die, a resin is injected and filled in the die, and cooled to obtain a resin molded product. In this method, the substrate sheet is peeled off and the transfer layer is transferred to the surface of the transfer object to decorate.

  As a method for producing a decorative sheet having both metallic luster and radio wave transmission used in these methods, there is one characterized in that a metal thin film layer is formed in an island shape on a base sheet using a vacuum deposition method ( For example, see Patent Document 1).

JP-A-62-174189

  However, in the method for producing a decorative sheet, in order to form an island shape in the metal thin film layer, the metal thin film layer must be formed extremely thin, and as a result, the decorative sheet is produced by the method for producing the decorative sheet. The decorative sheet cannot be applied to materials that do not have light-shielding properties and require an illumination function such as a display window, and is easily corroded in a high-temperature and high-humidity environment. There has been a problem that defects tend to occur. Furthermore, in the decorative sheet created by the above manufacturing method, the metal thin film layer needs to be formed in an island shape, and there is a problem that there is a limit to the type of metal that can be formed into such a shape by vacuum deposition. There was also.

  Therefore, the present invention eliminates the above problems, has a light shielding property and corrosion resistance, and does not limit the type of metal constituting the metal thin film layer, its manufacturing method, and decoration. The object is to provide a molded product.

  In order to achieve the above object, the decorative sheet, the manufacturing method thereof, and the decorative molded product of the present invention are configured as follows.

  That is, in the method for producing a decorative sheet of the present invention, the metal thin film layer and the resist layer are in contact with each other on the base sheet, and at least the resist layer of the metal thin film sheet formed so that the resist layer is on the surface, Using the nanoimprint method, a large number of fine recesses are formed in a part or all of the resist layer, and then the resist layer existing on the bottom surface of the formed many fine recesses is removed by dry etching. The metal thin film layer is exposed on the bottom surface of the concave portion, and then the metal thin film layer exposed on the bottom surface of the many fine concave portions is removed by wet etching, thereby forming a fine island shape in the resist layer and the metal thin film layer. It was configured as follows.

  In addition, the method for producing a decorative sheet according to the second aspect of the present invention provides a resist for a metal thin film sheet formed on a base sheet so that the metal thin film layer and the resist layer are in contact with each other and the resist layer is on the surface. A nanoimprint method was used to form a large number of fine recesses in part or all of the resist layer, and then the resist layer present on the bottom surface of the formed many fine recesses was removed by dry etching. The metal thin film layer is exposed on the bottom surfaces of a large number of fine recesses, then the metal thin film layer exposed on the bottom surfaces of the many fine recesses is removed by wet etching, and then an adhesive layer is formed on the resist layer. All or part of the resist layer and the metal thin film layer is formed in a fine island shape.

  Moreover, as a 3rd aspect of this invention, the manufacturing method of the decorating sheet of the 1st-2nd aspect can also be comprised so that a base sheet may have mold release property.

  Moreover, as a 4th aspect of this invention, the manufacturing method of the decorating sheet of the 1st-2nd aspect can also be comprised so that a base sheet may have adhesiveness.

  Moreover, as a 5th aspect of this invention, the manufacturing method of the decorating sheet of the 1st-4th aspect can also be comprised so that a metal thin film layer may consist of aluminum, copper, chromium, nickel, gold | metal | money, and silver.

  Moreover, as a 6th aspect of this invention, the manufacturing method of the decorating sheet of the 1st-5th aspect can also be comprised so that the thickness of a metal thin film layer may be 0.01 micrometer-1 micrometer.

  Further, as a seventh aspect of the present invention, in the method for producing a decorative sheet according to the first to sixth aspects, the gap in the portion in contact with the base sheet side layer of each fine island-shaped portion in the metal thin film layer portion is 0.01 μm. It can also comprise so that it may be -0.5m.

Moreover, as an eighth aspect of the present invention, in the method for producing a decorative sheet according to the first to seventh aspects, the area of the surface in contact with the layer on the side of each fine island-shaped base sheet in the metal thin film layer portion is 0.001 μm ^2. It can also be configured to be ˜4 μm ² .

  Moreover, as a 9th aspect of this invention, the manufacturing method of the decorating sheet of the 1st-8th aspect can also be comprised so that dry etching may be reactive gas etching.

  Moreover, as a 10th aspect of this invention, the manufacturing method of the decorating sheet of the 1st-9th aspect can also be comprised so that wet etching may be a dip type.

  According to an eleventh aspect of the present invention, a metal thin film layer having a fine island shape is formed on a part of or the entire surface of a base sheet, and at least the resist layer matches the island shape of the metal thin film layer. It can be configured to be formed on the surface in such a shape.

  As a twelfth aspect of the present invention, the decorative sheet according to the eleventh aspect can also be configured to form an adhesive layer on the resist layer.

  Moreover, as a thirteenth aspect of the present invention, the decorative sheet according to the eleventh to twelfth aspects can be configured such that the base sheet has releasability.

  Moreover, as a fourteenth aspect of the present invention, the decorative sheet according to the eleventh to twelfth aspects can be configured such that the base sheet has adhesiveness.

  As a fifteenth aspect of the present invention, the decorative sheets according to the eleventh to fourteenth aspects can be configured such that the metal thin film layer is made of Al, Cu, Cr, Ni, Au, or Ag.

  Moreover, as a sixteenth aspect of the present invention, the decorative sheets according to the eleventh to fifteenth aspects are configured such that the shortest portion of each fine island-shaped gap in the metal thin film layer portion is 0.01 μm to 0.5 μm. You can also

As a seventeenth aspect of the present invention, the decorative sheet of the 11 to 16 embodiment, the area of the surface in contact with the base sheet side of the layer of the fine island-like shape in the metal thin film layer portion is 0.001μm ² ~4μm ² It can also be configured to be.

  Moreover, as an eighteenth aspect of the present invention, the decorative sheet can be configured to be manufactured by any one of the manufacturing methods according to the first to tenth aspects.

  Moreover, as a nineteenth aspect of the present invention, a decorative molded product is formed by placing the decorative sheet according to any of the eleventh to thirteenth aspects or the fifteenth to eighteenth aspects in a mold and injecting a resin. It can also be configured as follows.

  As a twentieth aspect of the present invention, a decorative molded product is formed by placing the decorative sheet according to any of the fourteenth to nineteenth aspects in a mold, injecting a resin, and peeling the base sheet. It can also be configured.

  As a twenty-first aspect of the present invention, the decorative molded product can be configured such that any one of the decorative sheets described in the first to thirteenth and fifteenth to nineteenth aspects is integrally joined to the surface.

  The method for producing a decorative sheet according to the present invention includes a nanoimprint method on a resist layer of a metal thin film sheet that is formed on a substrate sheet so that the metal thin film layer and the resist layer are in contact with each other and the resist layer is on the surface. Are used to form a large number of fine recesses in a part or all of the resist layer, and then the resist layer present on the bottom surface of the formed many fine recesses is removed by dry etching. Since the metal thin film layer is exposed on the bottom surface of the substrate, and then the metal thin film layer exposed on the bottom surfaces of a number of fine recesses is removed by wet etching, a resist layer and a fine island shape are formed. It is possible to easily obtain a decorative sheet that has radio wave permeability, light shielding properties and corrosion resistance, and can freely select a metal constituting the metal thin film layer. A.

  Embodiments of the present invention will be described in detail with reference to the drawings.

  1 and 2 are cross-sectional views illustrating a method for producing a decorative sheet according to the present invention. In the figure, 1 is a base sheet, 2 is a metal thin film layer, 3 is a resist layer, 4 is a fine island-shaped portion in the resist layer, 5 is a fine recess, 6 is a remaining resist layer, and 7 is a fine film in the metal thin film layer. The island-shaped portion, 13 is an island-shaped portion, and 100 is a metal thin film sheet. In addition, the same code | symbol is attached | subjected about the same component in each figure.

  The method for manufacturing the decorative sheet 110 according to the first embodiment of the present invention is such that at least the metal thin film layer 2 and the resist layer 3 are in contact with each other on the base sheet 1 and the resist layer 3 is on the surface. In the resist layer 3 of the metal thin film sheet 100 (see FIGS. 1A and 2A), a large number of fine recesses 5 are formed in part or all of the resist layer 3 by using a nanoimprint method ( Next, the resist layer 3 present on the bottom surfaces of the numerous fine recesses 5 formed is removed by dry etching, and a metal is formed on the bottom surfaces of the numerous fine recesses 5 formed. The thin film layer 2 is exposed (see FIGS. 1 (c) and 2 (c)), and then the metal thin film layer 2 exposed on the bottom surfaces of a large number of fine recesses 5 is removed by wet etching, whereby the resist layer 3 and All of the metal thin film layer 2 Or part is configured to form a fine island-like shape 13 (see FIG. 1 (d), the Figure 2 (d)).

  The metal thin film sheet 100 used in the present invention is formed on the base sheet 1 at least so that the metal thin film layer 2 and the resist layer 3 are in contact with each other and the resist layer 3 is on the surface. Moreover, the base sheet 1 may have releasability or may have adhesiveness. Below, the structure method of the metal thin film sheet 100 is demonstrated about the case where the base sheet 1 has a mold release property, and the case where it has adhesiveness, respectively.

  First, the configuration of the metal thin film sheet 100 when the base sheet 1 has releasability will be described. First, a base sheet 1 having releasability is prepared. As the base sheet 1 having releasability, a resin sheet such as a polypropylene resin, a polyethylene resin, a polyamide resin, a polyester resin, an acrylic resin, a polyvinyl chloride resin, an aluminum foil, a copper foil A sheet having releasability can be used as a base sheet of a normal transfer material, such as a metal foil such as glassine paper, coated paper, cellophane, or a cellulosic sheet, or a composite of the above sheets. When the surface of the base sheet 1 has fine irregularities, the irregularities are copied to the metal thin film layer 2 and a surface shape such as matte or hairline can be expressed.

  Next, if necessary, the release layer 9 may be entirely formed on the base sheet 1 (see FIG. 3A). The release layer 9 is released from the metal thin film layer 2 together with the base sheet 1 when the base sheet 1 is peeled after the transfer (see FIG. 3B). As a material of the release layer 9, melamine resin release agent, silicone resin release agent, fluororesin release agent, cellulose derivative release agent, urea resin release agent, polyolefin resin release agent Paraffin type release agents and composite release agents thereof can be used. As a method for forming the release layer, there are a coating method such as a roll coating method and a spray coating method, a printing method such as a gravure printing method and a screen printing method.

  Next, the release layer 10 may be entirely formed on the release layer 9 (see FIG. 3A). The release layer 10 is a layer that peels from the base sheet 1 or the release layer 9 and becomes the outermost surface of the transfer object when the base sheet 1 is peeled after transfer or after simultaneous molding transfer (FIG. 3B). reference). The release layer 10 may be made of acrylic resin, polyester resin, polyvinyl chloride resin, cellulose resin, rubber resin, polyurethane resin, polyvinyl acetate resin, or vinyl chloride-vinyl acetate copolymer. Copolymers such as system resins and ethylene-vinyl acetate copolymer resins may be used. When the release layer requires hardness, a photo-curing resin such as an ultraviolet curable resin, a radiation curable resin such as an electron beam curable resin, or a thermosetting resin may be selected and used. The release layer may be colored or uncolored. As a method for forming the release layer, there are a coating method such as a gravure coating method, a roll coating method and a comma coating method, a printing method such as a gravure printing method and a screen printing method.

  Next, the metal thin film layer 2 is formed on the entire surface. The metal thin film layer 2 is for expressing metallic luster and is formed by a vacuum deposition method, a sputtering method, an ion plating method, a plating method, or the like. Metals such as aluminum, tin, nickel, gold, platinum, chromium, iron, copper, indium, silver, titanium, lead, and zinc, and alloys or compounds thereof are used depending on the metallic luster color to be expressed. When the thickness of the metal thin film layer 2 is less than 0.01 μm, the metallic luster of the metal thin film layer 2 is lowered, and when it exceeds 1 μm, etching takes time and productivity is lowered, so that 0.01 to 1 μm is preferable.

  Moreover, when providing the metal thin film layer 2, in order to improve the adhesiveness of the metal thin film layer 2 and the layer which touches the base sheet 1 side of the metal thin film layer 2, you may provide the anchor layer 11 (FIG. 3 ( a)). As the material of the anchor layer 11, two-component cured urethane resin, thermosetting urethane resin, melamine resin, cellulose ester resin, chlorine-containing rubber resin, chlorine-containing vinyl resin, acrylic resin, epoxy resin, vinyl A copolymer resin may be used. Examples of methods for forming the front anchor layer and the rear anchor layer include coating methods such as gravure coating, roll coating, and comma coating, printing methods such as gravure printing, and screen printing.

  Next, the resist layer 3 is formed on the entire surface of the metal thin film layer 2 or partially to obtain a decorative sheet 110. The resist layer 3 is a layer that can protect the metal thin film layer 2 and leave only the portion of the metal thin film layer 2 on which the resist layer 3 is formed in a metal thin film removal step by wet etching described later. When the thermal nanoimprint method is used in the step of forming a recess of the resist layer 3 by the nanoimprint method to be described later, the material of the resist layer 3 is vinyl resin, amide resin, polyester resin, acrylic resin, polyurethane resin, polyvinyl It is preferable to use an ink containing a resin such as an acetal resin, a polyester urethane resin, a cellulose ester resin, or an alkyd resin as a binder and an additive such as an extender pigment or a colorant such as a pigment or dye. When the optical nanoimprint method is used, the resist layer 3 may be formed using a photocurable resin such as an acrylic resin, a urethane resin, or an epoxy resin. When the room temperature nanoprint method is used, as the resist layer 3, FOX (registered trademark) -12 FLOWABLE OXIDE, FOX (registered trademark) -14 FLOWABLE OXIDE, FOX (registered trademark) -15 FLOWABLE OXIDE, manufactured by Toray Dow Corning Co., Ltd. It is good to form using sol-gel type materials, such as FOX (trademark) -16 FLOWABLE OXIDE and these mixtures. As a method for forming the resist layer 3, in addition to a normal printing method such as an offset printing method, a gravure printing method, or a screen printing method, a coating method such as a gravure coating method, a roll coating method, a comma coating method, or a lip coating method is adopted. You can also

  The resist layer 3 is preferably formed to a thickness of 0.1 to 10 μm. When the thickness of the resist layer 3 is less than 0.1 μm, chemical resistance is insufficient, and portions other than the fine recesses 5 are easily etched, and when the thickness of the resist layer 3 exceeds 10 μm, the fine recesses 5 This is because the nanoimprint process with a considerably high aspect ratio results in a poorly releasable property between the stamper and the decorative sheet 110 and the productivity is lowered.

  The configuration of the metal thin film sheet 100 is not limited to the above-described embodiment. For example, in addition to the metallic luster pattern formed by the metal thin film layer 2, the pattern layer 12 is formed to decorate various patterns and characters. You may do it (refer Fig.3 (a)). As a material of the pattern layer 12, a resin such as a polyvinyl resin, a polyamide resin, a polyester resin, an acrylic resin, a polyurethane resin, a polyvinyl acetal resin, a polyester urethane resin, a cellulose ester resin, or an alkyd resin is used as a binder. And a color ink containing an appropriate color pigment or dye as a colorant may be used. As a method for forming the printing layer, a normal printing method such as a gravure printing method, a screen printing method, or an offset printing method may be used. In particular, the offset printing method and the gravure printing method are suitable for performing multicolor printing and gradation expression. In the case of a single color, a coating method such as a gravure coating method, a roll coating method, or a comma coating method may be employed. The design layer may be provided in an arbitrary pattern depending on the design to be expressed.

  Secondly, a configuration method of the metal thin film sheet 100 when the base sheet 1 has adhesion will be described. First, the base sheet 1 is prepared. As the base sheet 1, a thermoplastic resin sheet such as a polypropylene resin, a polyethylene resin, a polyamide resin, a polyester resin, an acrylic resin, a polyvinyl chloride resin, or a polyurethane resin, an epoxy resin, a polyimide resin, etc. A base sheet 1 of a normal decorative sheet 110 such as a thermosetting sheet, a transparent member such as a glass plate, a cellulosic sheet such as cellophane, or a composite of the above respective sheets is used. But is not limited to the above. The base sheet 1 is a layer that becomes the outermost surface of the object to be decorated after laminating or placing the base sheet in a mold and decorating simultaneously.

  Next, the metal thin film layer 2 is formed on the entire surface. The metal thin film layer 2 is for expressing a metallic luster, and a metal thin film having releasability with respect to a method for forming the metal thin film layer 2, a type of metal to be formed, and a thickness of the metal thin film layer 2 to be formed. This is the same as the method for constructing the sheet 100.

  Moreover, when providing the metal thin film layer 2, in order to improve the adhesiveness of the metal thin film layer 2 and the layer which touches the base sheet side, and the metal thin film layer 2, you may provide an anchor layer (not shown). The material and forming method of the anchor layer are the same as those of the metal thin film sheet 100 having releasability.

  Next, the resist layer 3 is formed on the entire surface of the metal thin film layer 2 or partially to obtain a decorative sheet 110. The resist layer 3 is a layer that can protect the metal thin film layer 2 and leave only the portion of the metal thin film layer 2 on which the resist layer 3 is formed in a metal thin film removal step by wet etching described later. Moreover, about the formation method of the resist layer 3, the kind of resin to form, and the thickness of the resist layer 3 to form, it is the same as that of the structure method of the metal thin film sheet 100 which has mold release property.

  The configuration of the metal thin film layer 2 is not limited to the above-described mode. For example, in addition to the metallic luster pattern formed by the metal thin film layer 2, a pattern layer is formed to decorate various patterns and characters. (Not shown). About the material and formation method of a pattern layer, it is as having mentioned above with the metal thin film sheet 100 which has mold release property.

  Next, on the resist layer 3 of the metal thin film sheet 100 configured as described above, a number of fine recesses 5 are formed in a part or all of the resist layer 3 by using a nanoimprint method.

  The nanoimprint method is a processing method in which a stamper provided with fine convex portions is pressed against the resist layer 3 to form fine concave portions 5 in the resist layer 3. Typical examples of the nanoimprint method include a thermal nanoimprint method, an optical nanoimprint method, and a room temperature nanoimprint method. Below, the method of forming the fine recessed part 5 in the resist layer 3 by each method of the thermal nanoimprint method, the optical nanoimprint method, and the room temperature nanoimprint method is demonstrated.

  As a method of forming the fine recesses 5 in the resist layer 3 using the thermal nanoimprint method, a stamper made of nickel electroforming is first produced from a mother die drawn with an electron beam or the like, and then a resist layer is formed on the resist layer. The stamper is removed from the resist layer 3 after cooling and a fine recess 5 is formed in the resist layer 3. The temperature at the time of pressing is set to be higher than the softening point of the resist layer 3 and lower than the thermal decomposition temperature, and the pressure is generally set to several MPa to several tens of MPa. Under the conditions, the stamper is pressed against the resist layer 3 for several seconds to several minutes, then rapidly cooled or naturally cooled, and left until the surface of the resist layer 3 becomes below the softening point. In the thermal nanoimprint method using a roll, the pressing time and the cooling time under high temperature and high pressure are reduced, and the productivity is improved.

  As a method for forming the fine recesses 5 in the resist layer 3 by the optical nanoimprint method, first, a transparent stamper that can transmit ultraviolet light such as quartz is prepared, and a resist layer using a photo-curing resin that cures the ultraviolet light with ultraviolet light. In this method, after placing on 3 and pressing, it is cured by irradiating with ultraviolet light, the stamper is removed from the resist layer 3, and a minute recess 5 is formed in the resist layer 3. There is an advantage that it is possible to align with other layers through the stamper because the stamper is transparent because the pressure does not need to be high when pressing and the pressure can be several MPa or less, and the stamper is transparent.

  As a method of forming a recess in the resist layer 3 by the room temperature nanoimprint method, a sol-gel material such as FOX (registered trademark) -12 FLOWABLE OXIDE, FOX (registered trademark) -14 FLOWABLE manufactured by Toray Dow Corning Co., Ltd. is used as a resist material. By using a sol-gel material such as OXIDE, FOX (registered trademark) -15 FLOWABLE OXIDE, FOX (registered trademark) -16 FLOWABLE OXIDE, and a mixture thereof, the stamper is pressed against the resist layer 3 at room temperature. 3 is a method of forming a minute recess 5 in the substrate 3. The pressure at the time of pressing is generally set to several MPa to several tens of MPa. There is an advantage that a cooling process is unnecessary.

  The fine recesses formed in all or part of the resist layer 3 by various methods of the nanoimprint method are formed so as to have a width of 0.01 μm to 1 μm. More preferably, it is good to form in the range of 0.01 micrometer-0.1 micrometer. If the width of the fine concave portion 5 is increased beyond 1 μm, the gap between the fine island-shaped convex portion and the convex portion made of the resist layer 3 and the metal thin film layer 2 described later is widened. Light leaks and the metallic gloss of the decorative sheet 110 is lost. On the other hand, if the width of the concave portion is less than 0.01 μm, the fine island-shaped convexity consisting of the resist layer 3 and the metal thin film layer 2 described later is formed. This is because the gap between the portion and the convex portion is also narrowed, a tunnel effect occurs in the metal thin film layer 2, and the metal thin film layer 2 does not have radio wave transmission, so the decorative sheet 110 also does not have radio wave transmission.

  Next, the remaining resist layer 6 present on the bottom surfaces of a large number of fine recesses 5 formed by various nanoimprint methods is removed by dry etching, and the metal thin film layer 2 is exposed on the bottom surfaces of the formed many fine recesses 5.

  Dry etching is a method of etching a material with reactive gas, ions, or radicals. The dry etching method includes reactive gas etching that exposes the material to the reaction gas, reactive ion etching that ionizes and radicalizes the gas with plasma, and ion beam etching that etches the target with inert ions as a beam. , Reactive ion beam etching that etches the target in the form of a chemically active ion beam, the solid material is irradiated with strong laser light, and the elements that make up the target are in various forms (atoms, molecules, radicals, clusters, There is reactive laser beam etching that explodes with droplets and their ions, etc., and etches the target surface, but the residual resist layer 6 present on the bottom surface of the fine recess 5 is removed by any method. May be. In particular, in the case of reactive ion etching, a fluorine-based gas such as sulfur hexafluoride, carbon tetrafluoride, or trifluoromethane is used as an etching gas. In the case of reactive gas etching, xenon difluoride is used as an etching gas. The remaining resist layer 6 present on the bottom surface of the recess 5 may be removed.

  By performing this step, after forming the fine recess 5 in the resist layer 3 in the above step, the remaining resist layer 6 present on the bottom surface of the fine recess 5 can be completely removed. The removal method includes wet etching and dry etching, but anisotropic etching is required to completely remove the remaining resist layer 6 existing on the bottom surface of the minute recess 5, and therefore dry etching is more preferable. . Also, dry etching can be easily performed since there is no post-processing step as in wet etching described later. In addition, by this step, only the portion of the metal thin film layer 2 protected by the fine island-shaped portion 4 in the resist layer can be left in the wet etching step described later.

  Next, the metal thin film layer 2 exposed on the bottom surface of the fine concave portion 5 is removed by wet etching to form a fine island-like shape 13 composed of a resist layer and a metal thin film layer.

  The decorative sheet 110 is completed by this process. In the wet etching, the metal thin film sheet 100 is immersed in a container filled with a metal etching solution, and a dip type that erodes the exposed metal thin film layer 2, and the metal etching solution is sprayed out in a mist form to form the metal thin film sheet 100. There is a spray type to spray and a spin type to attach a metal thin film sheet 100 to a turntable called a spinner and drop a metal etching solution. Either method can be used to protect the fine island-shaped portion 4 in the resist layer. The metal thin film layer portion that is not present may be removed. Of these methods, the dip method is more preferable because it can be most easily performed. As the metal etching solution, a weakly acidic or weakly alkaline aqueous solution is used, and the concentration, immersion temperature, and immersion time of the metal etching solution may be appropriately selected depending on the material and thickness of the metal thin film layer 2.

  Through the series of etching steps, the resist layer 3 and the metal thin film layer 2 have a fine island shape 13 in whole or in part.

Next, the island shape 13 will be described. The island shape 13 is formed from a fine island shape portion in the resist layer (hereinafter referred to as resist layer island portion 4) and a fine island shape portion in the metal thin film layer (hereinafter referred to as metal thin film layer island portion 7). It is configured (see FIG. 4). Examples of the surface shape of the resist layer island-shaped portion 4 include a polygon, a circle, or a combination of these (see FIG. 5). Further, as the cross-sectional shapes of the resist layer island-like portion 4 and the metal thin film layer island-like portion 7, there are U-shaped, V-shaped and U-shaped uneven shapes (see FIGS. 6A to 6C). ). However, these shapes are not limited to the above. In order for the decorative sheet to have metallic luster and radio wave transmission, the area of the surface of the metal thin film layer in contact with the layer on the substrate sheet side of each fine island-shaped portion, that is, the island-shaped metal thin film layer portion 7 is the substrate sheet. An area S (hereinafter referred to as a reference island area S) of the surface in contact with the one side layer, and a gap in a portion of each metal island layer in contact with the base sheet side layer, that is, an island metal thin film It is preferable that a gap L (hereinafter, referred to as a reference inter-island distance L) at a portion of the layer portion 7 in contact with the layer on the base sheet 1 side is within a certain range. That is, it is preferable that the reference island area S is in the range of 0.001 μm ^{2 to} 4 μm ² , and the reference inter-island distance L is in the range of 0.01 μm to 0.5 μm. This is because when the metal thin film layer island portion 7 is in the above condition, the decorative sheet 110 has a design property as a metallic luster, a light shielding property and a radio wave transmitting property. That is, with respect to the reference island-shaped area S, if the area S exceeds 4 μm ² , the decorative sheet 110 becomes less likely to have radio wave transmission, and conversely, if the area S is less than 0.001 μm ² , the metal thin film layer has a holographic effect. Thus, the decorative sheet 110 is less likely to have a design as a metallic luster. As for the distance L between the reference islands, if the distance L exceeds 0.5 μm, the light shielding property of the decorative sheet 110 decreases, and conversely, if the distance L between the reference islands is less than 0.01 μm, the decorative sheet is caused by the tunnel effect. 110 becomes difficult to have radio wave transmission. For this reason, it is preferable that the reference island area S and the reference island distance L are in the above ranges.

  In the range where the metal thin film layer island-like portion 7 satisfies the above conditions, even if the metal thin film layer 2 is formed of a highly conductive material, the decorative sheet will exhibit insulation or radio wave transmission. Moreover, since the obtained metal thin film layer island-like site 7 can be formed only on a part of the metal thin film layer 2, the appearance design is almost the same as that of the metal thin film layer 2 before making it into a fine shape, Although it seems that the single metal thin film layer 2 is formed on the entire surface, the metal thin film layer 2 having the contradictory functions of electrical conductivity and insulation can be formed in a pattern in terms of electrical performance ( (Refer FIG.2 (d)).

  If necessary, the adhesive layer 8 may be formed on the resist layer 3 entirely or partially (see FIGS. 7 and 8). The adhesive layer 8 adheres each of the above layers to the surface to be decorated. Further, the adhesive layer 8 is formed in a portion to be bonded. That is, when the part to be bonded is the entire surface, the adhesive layer 8 is formed on the entire surface. If the part to be bonded is partial, the adhesive layer 8 is partially formed. As the adhesive layer 8, a heat-sensitive or pressure-sensitive resin suitable for the material to be decorated is used as appropriate. For example, when the material to be decorated is an acrylic resin, an acrylic resin may be used. If the material to be decorated is polyphenylene oxide / polystyrene resin, polycarbonate resin, styrene copolymer resin, or polystyrene blend resin, acrylic resin, polystyrene resin, polyamide having affinity with these resins A series resin or the like may be used. Furthermore, when the material to be decorated is a polypropylene resin, chlorinated polyolefin resin, chlorinated ethylene-vinyl acetate copolymer resin, cyclized rubber, and coumarone indene resin can be used. Examples of the method for forming the adhesive layer 8 include a coating method such as a gravure coating method, a roll coating method, and a comma coating method, a printing method such as a gravure printing method, and a screen printing method.

  In the decorative sheet 110 of the present invention that can be produced in this manner, a metal thin film layer 7 having a fine island-like shape is formed on a part or the entire surface of the base sheet 1, and the metal thin film layer is formed thereon. 7 is formed so that at least the resist layer 4 is formed on the surface so as to be united with 7.

  As a result of the construction as described above, the metal thin film layer 2 that has conventionally served only as a design exhibiting a metallic luster can also serve as a conductive circuit. When connected to an external printed board, a touch switch or It can be used for applications such as antennas.

  The decorative sheet 110 configured as described above can decorate the molded resin 16 by using it as follows.

  A method of decorating the surface of the resin molded product to be decorated using the simultaneous molding insert molding method by using the decorative sheet 110 having the base sheet having adhesion as described above as a constituent element will be described ( (Refer FIG. 9 (a)-(c)).

  First, the decorative sheet 110 is fed into a molding die composed of the movable die 14 and the fixed die 15 (see FIG. 9A). In that case, the sheet decoration sheet 110 may be sent one by one, or a necessary part of the long decoration sheet 110 may be sent intermittently. When using the long decorative sheet 110, it is preferable to use a feeding device having a positioning mechanism so that the register of the pattern of the decorative sheet 110 matches the molding die. Further, when the decorative sheet 110 is intermittently fed, if the decorative sheet 110 is fixed by the movable type and the fixed type after the position of the decorative sheet 110 is detected by the sensor, the decorative sheet 110 is always added at the same position. The decorative sheet 110 can be fixed, and the pattern is not misaligned, which is convenient. After closing the molding die, the molten resin is injected and filled into the die from the gate, and the decoration sheet 110 is adhered to the surface at the same time as the decoration is formed (see FIG. 9B). After the decorative molded product that is the object to be decorated is cooled, the molding die is opened and the decorative molded product 111 is taken out (see FIGS. 9C and 9D).

  Next, using the decorative sheet 110 having the above-described base sheet having releasability as a constituent element, decoration is performed on the surface of the decorative molded product, which is a transfer object, using a simultaneous molding transfer method by injection molding. A method will be described (see FIGS. 10A to 10E). First, the decorative sheet 110 is fed into a molding die composed of the movable die 14 and the fixed die 15 (see FIG. 10A). In that case, the sheet decoration sheet 110 may be sent one by one, or a necessary part of the long decoration sheet 110 may be sent intermittently. When using the long decorative sheet 110, it is preferable to use a feeding device having a positioning mechanism so that the register of the pattern of the decorative sheet 110 matches the molding die. Further, when the decorative sheet 110 is intermittently fed, if the decorative sheet 110 is fixed by the movable type and the fixed type after the position of the decorative sheet 110 is detected by the sensor, the decorative sheet 110 is always added at the same position. The decorative sheet 110 can be fixed, and the pattern is not misaligned, which is convenient. After closing the molding die, the molten resin is injected and filled into the die from the gate, and at the same time as the transfer object is formed, the decorative sheet 110 is adhered to the surface (see FIG. 10B). After the decorative molded product, which is the transfer target, is cooled, the molding die is opened and the resin molded product is taken out (see FIGS. 10C and 10D). Finally, the substrate sheet 1 is peeled off (see FIG. 10E) to complete the transfer (see FIG. 10F).

  Finally, a method for decorating the surface of the transfer object using the transfer method using the decorative sheet 110 having the above-described base sheet having releasability or adhesion as a constituent element will be described. First, the adhesive layer 8 side of the decorative sheet 110 is brought into close contact with the surface of the transfer object. Next, using a transfer machine such as a roll transfer machine or an up-down transfer machine equipped with a heat-resistant rubber-like elastic body such as silicon rubber, a heat-resistant rubber-like condition set at a temperature of about 80 to 260 ° C. and a pressure of about 490 to 1960 Pa. Heat and pressure are applied from the base sheet 1 side of the decorative sheet 110 via the elastic body. By doing so, the adhesive layer 8 adheres to the surface of the transfer object. Finally, when the base sheet 1 is peeled after cooling, peeling occurs at the interface between the base sheet 1 and the release layer, and the transfer is completed.

  As the material to be transferred, those made of various materials such as a resin molded product can be used. The transfer object may be transparent, translucent, or opaque. Further, the transfer object may be colored or not colored. Examples of the resin include general-purpose resins such as polystyrene resin, polyolefin resin, ABS resin, AS resin, and AN resin. Also, general engineering resins such as polyphenylene oxide / polystyrene resins, polycarbonate resins, polyacetal resins, acrylic resins, polycarbonate modified polyphenylene ether resins, polybutylene terephthalate resins, ultrahigh molecular weight polyethylene resins, polysulfone resins, polyphenylene sulfide resins Super engineering resins such as polyphenylene oxide resins, polyarylate resins, polyetherimide resins, polyimide resins, liquid crystal polyester resins, and polyallyl heat-resistant resins can also be used. Furthermore, composite resins to which reinforcing materials such as glass fibers and inorganic fillers are added can also be used.

  The present invention will be described more specifically with reference to the following examples and comparative examples, but the present invention is not limited to these examples.

  After using a 38 μm-thick polyester resin film as the base sheet, a melamine resin release layer, an acrylic resin release layer, and a urethane resin anchor layer before metal deposition are sequentially formed on the base sheet by gravure printing. A metal vapor deposition layer made of aluminum having a thickness of 0.06 μm is formed by vacuum vapor deposition, a resist layer made of vinyl resin having a thickness of 0.2 μm is formed on a part of the metal vapor deposition layer by gravure printing, and a metal thin film A sheet was obtained. Next, a pressure of 5 MPa under a heating of 100 ° C. with a nanoimprint mold made of nickel electroforming in which a square lattice pattern having a width of 0.1 μm and a pitch of 0.7 μm is formed in a convex shape with a thickness of 0.18 μm. When the mold was released from the mold, fine recesses formed of grooves of the lattice pattern were formed on the resist layer surface.

Thereafter, the remaining resist layer remaining in the fine recesses was removed by dry etching. Next, when immersed in a metal etching solution made of 0.2% potassium hydroxide aqueous solution for 2 seconds, only the portion where the resist layer is not formed on the metal thin film layer is removed, and a part of the metal thin film layer is 0.36 μm ² . A decorative sheet formed into a fine shape having a size was obtained. Next, an adhesive layer made of an acrylic resin was formed on the entire decorative sheet by a reverse coating method. Finally, the decorative sheet having the adhesive layer formed on the entire surface was transferred to the surface of the acrylic resin molded article by a molding simultaneous transfer method to obtain a decorative molded article.

  The obtained decorative molded product is the same as the conventional molded product with a metallic tone, but the metal thin film portion formed in a fine shape has sufficient radio wave permeability, and is not so. The part had electromagnetic wave shielding properties. As a result, the reception of the built-in antenna at the lower part of the metal thin film portion formed in a fine shape was good, and the other portion was able to block harmful electromagnetic waves and protect the electronic components from malfunctioning due to jamming radio waves. In addition, the decorative molded product had light shielding properties and corrosion resistance.

  An acrylic resin film having a thickness of 100 μm is used as a base sheet, and after a vinyl resin pattern layer and a urethane resin anchor layer before metal deposition are formed on the base sheet by gravure printing, the thickness is reduced to 0 by electroless plating. A metal plating layer made of 1 μm copper was formed. Then, a resist layer made of acrylic resin having a thickness of 0.1 μm is formed on a part of the metal plating layer by gravure printing, and then a regular hexagonal honeycomb pattern having a width of 0.05 μm and a side of 0.4 μm is thick. A nanoimprint mold made of nickel electroforming formed in a convex shape with a thickness of 0.08 μm, pressed at a pressure of 10 MPa under heating at 120 ° C., cooled with water and left for 10 minutes, and then the mold was released. A concave portion formed of the groove of the honeycomb pattern was formed on the surface of the resist layer.

Next, after removing the remaining resist layer remaining in the minute recesses by dry etching, and immersing in a metal etching solution made of 0.3% iron chloride aqueous solution for 2 seconds, only the portion of the metal thin film layer where the resist layer was removed is removed. As a result, a metal thin film sheet in which a part of the metal thin film layer was formed into a fine shape having a size of about 0.4 μm ² was obtained. Next, an adhesive layer made of a vinyl resin was formed on the entire decorative sheet by a gravure printing method. Finally, the decorative sheet having the adhesive layer formed on the entire surface was adhered to the surface of the acrylic resin molded article by a simultaneous molding method to obtain a decorative molded article.

  The resulting decorative molded product has corrosion resistance and is apparently the same as a conventional molded product with a metallic tone, but the metal thin film portion formed in a fine shape is insulative. The part which has and is not so has conductivity. As a result, this conductive pattern portion could function as a capacitance switch pattern.

  (Comparative Example 1 and Comparative Example 2) Comparative Example 1 and Comparative Example 1 were the same as Example 1 or Example 2 except that the metal thin film layers of Examples 1 and 2 were formed by the conventional vacuum deposition method using tin. Example 2 was performed. Further, Comparative Example 1 and Comparative Example 2 were performed in the same manner as in Example 1 or Example 2 except that the concave portions formed by the lattice pattern of Example 1 or the honeycomb pattern of Example 2 were formed by conventional photolithography. Carried out.

  None of the above comparative examples lacked corrosion resistance and light shielding properties. In addition, because the size of islands and the gap between islands is not uniform, there are variations in insulation and radio wave transmission depending on the production lot, and electrical characteristics compared to molded products with the decorative sheet of the present invention attached Was inferior.

  INDUSTRIAL APPLICABILITY The present invention can be suitably used in various molded products such as communication devices such as mobile phones, information devices inside automobiles, and home appliances and is industrially useful.

It is sectional drawing which shows one Example of the manufacturing method of the decorating sheet which concerns on this invention. It is sectional drawing which shows one Example of the manufacturing method of the decorating sheet which concerns on this invention. It is sectional drawing which shows one Example of a metal thin film sheet. It is a perspective view which shows one Example of the decorating sheet obtained by the manufacturing method of the decorating sheet which concerns on this invention. It is a perspective view which shows one Example of the decorating sheet obtained by the manufacturing method of the decorating sheet which concerns on this invention. It is sectional drawing which shows one Example of the decorating sheet obtained by the manufacturing method of the decorating sheet which concerns on this invention. It is sectional drawing which shows one Example of the decorating sheet obtained by the manufacturing method of the decorating sheet which concerns on this invention. It is sectional drawing which shows one Example of the decorating sheet obtained by the manufacturing method of the decorating sheet which concerns on this invention. It is sectional drawing which shows one Example of the manufacturing method of the decorative molded product which concerns on this invention. It is sectional drawing which shows one Example of the manufacturing method of the decorative molded product which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base sheet 2 Metal thin film layer 3 Resist layer 4 Resist layer island-shaped part 5 Fine-shaped recessed part 6 Residual resist layer 7 Metal thin film layer island-shaped part 8 Adhesive layer 9 Release layer 10 Peeling layer 11 Anchor layer 12 Pattern layer 13 Island Shape 14 Movable Type 15 Fixed Type 16 Molded Resin 17 Transfer Layer 100 Metal Thin Film Sheet 110 Decorated Sheet 111 Decorated Molded Product S Reference Island Area L Reference Island Distance

Claims (21)

The resist layer of the metal thin film sheet formed at least so that the metal thin film layer and the resist layer are in contact with each other on the base sheet, and the resist layer is on the surface. A plurality of fine recesses are formed, and then the resist layer present on the bottom surfaces of the formed many fine recesses is removed by dry etching to expose the metal thin film layer on the bottom surfaces of the formed many fine recesses, The metal thin film layer exposed on the bottom surfaces of a large number of fine recesses is removed by wet etching to form all or part of the resist layer and the metal thin film layer in a fine island shape. A method for producing a decorative sheet. The resist layer of the metal thin film sheet formed at least so that the metal thin film layer and the resist layer are in contact with each other on the base sheet, and the resist layer is on the surface. A plurality of fine recesses are formed, and then the resist layer present on the bottom surfaces of the formed many fine recesses is removed by dry etching to expose the metal thin film layer on the bottom surfaces of the formed many fine recesses, The metal thin film layer exposed on the bottom surfaces of a large number of fine recesses is removed by wet etching, and then an adhesive layer is formed on the resist layer, whereby all or part of the resist layer and the metal thin film layer are formed into fine islands. A method for producing a decorative sheet, wherein the decorative sheet is formed into a shape. The method for producing a decorative sheet according to claim 1, wherein the base sheet has releasability. The manufacturing method of the decorating sheet in any one of Claims 1-2 in which a base sheet has adhesiveness. The method for producing a decorative sheet according to any one of claims 1 to 4, wherein the metal thin film layer comprises any one of aluminum, nickel, gold, copper, silver, titanium, and zinc. The thickness of a metal thin film layer is 0.01 micrometer-1 micrometer, The manufacturing method of the decorating sheet in any one of Claims 1-5. The method for producing a decorative sheet according to any one of claims 1 to 6, wherein a gap in a portion in contact with the layer on the substrate sheet side of each fine island-shaped portion in the metal thin film layer is 0.01 µm to 0.5 m. Decorative sheet area of the surface in contact with the substrate sheet side of the layer of the fine island-like shape portion of the metal thin film layer produced by the method according to any one to claims 1 to 7 is 0.001μm ² ~4μm ² Manufacturing method. The method for producing a decorative sheet according to any one of claims 1 to 8, wherein the dry etching is reactive gas etching. The method for producing a decorative sheet according to any one of claims 1 to 9, wherein the wet etching is a dip type. A metal thin film layer having a fine island shape is formed on a part or the entire surface of the base sheet, and at least a resist layer is formed on the surface so as to match the island shape of the metal thin film layer. A decorative sheet characterized by that. The decorative sheet according to claim 11, wherein an adhesive layer is formed on the resist layer. The decorating sheet according to any one of claims 11 to 12, wherein the base sheet has releasability. The decorating sheet according to any one of claims 11 to 12, wherein the base sheet has adhesiveness. The decorative sheet according to any one of claims 11 to 14, wherein the metal thin film layer is made of aluminum, nickel, gold, copper, silver, titanium, or zinc. The decorative sheet according to any one of claims 11 to 15, wherein a gap in a portion of each metal thin film layer in contact with the layer on the substrate sheet side of each fine island-shaped portion is 0.01 µm to 0.5 µm. Decorative sheet area of the surface in contact with the substrate sheet side of the layer of the fine island-like shape portion of the metal thin film layer produced by the method according to any one to claims 11 to 16 is 0.001μm ² ~4μm ² . A decorative sheet produced by the method according to claim 1. The decorative molded product shape | molded by arrange | positioning the decorating sheet in any one of Claims 11-13, 15-18 in a metal mold | die, and injecting resin. The decorative molded product shape | molded by arrange | positioning the decorating sheet in any one of Claims 14-18 in a metal mold | die, injecting resin, and peeling a base sheet. The decorative molded product which joined the decorative sheet in any one of Claims 11-18 integrally to the surface.

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