JP4538311B2 - Method for producing decorative molded body - Google Patents

Description

  The present invention is a molded body such as a push button switch, a casing, a cover member for a liquid crystal panel, etc. used for various electric / electronic devices such as a mobile phone, a portable information terminal, and an AV device, and represents characters, symbols, and the like. The present invention relates to a method for manufacturing a decorative molded body that has been decorated with a pattern or various color tones.

  Various electrical and electronic equipment members such as mobile phones, personal digital assistants, AV equipment, etc. have been designed in various ways due to individual and hobby requirements. In particular, mobile phones are undergoing intense fashion competition, and the demand for design is severe. Under such circumstances, the popularity of the molded body used for the mobile phone, that is, the design for decorating the casing constituting the mobile phone, the push button switch, the cover member for the liquid crystal panel, etc. in a metallic luster tone. There is.

  As a method of decorating a molded body constituting a part of an electric / electronic device with a metallic luster, a method of immersing the molded body in a plating solution and providing a metal thin film layer such as nickel or chromium by a chemical plating method (for example, JP 2000-268666 A; Patent Document 1) or a method in which a molded body is placed in a vacuum atmosphere and a metal thin film layer such as aluminum or chromium is provided by a physical plating method such as a vacuum deposition method or a sputtering method (for example, No. 2003-197063; Patent Document 2), and a method of transferring a hot stamp foil formed with a metal thin film layer such as aluminum or chromium to a molded body, and applying a polymer paint in which metal foil pieces are dispersed to apply metal A method of providing a glossy layer by overlapping foil pieces is known.

  Among these methods, the method of transferring the hot stamping foil to the molded body and providing the metal thin film layer on the surface of the molded body can form the metal thin film layer at a desired position of the molded body, and implement various designs. Since it has advantages such as being relatively easy to manufacture, stable in quality, easy production and high mass productivity, it is often used.

  However, using any of the methods described above, only a decoration that allows the user to visually recognize a uniform metallic glossy tone is given, so there is no significant difference from a general design that imitates a metal material. The design was not chipped or interesting.

Therefore, as a decoration that gives rise to a high-class feeling, not just a metallic glossy color tone, there have been devised decorations such as a matte metallic tone with no gloss or a hairline metallic tone that allows parallel thin lines to be seen. The method uses, for example, a technique for forming a concavo-convex pattern in advance on the surface of a molded body described in Japanese Patent Application Laid-Open No. 2003-109450 (Patent Document 3). That is, a hot stamping foil is transferred to a molded body having irregularities, thereby forming a design shaped by irregularities, and decorating with a matte metallic tone or a hairline metallic tone.
JP 2000-268666 A Japanese Patent Laid-Open No. 2003-197063 JP 2003-109450 A

  However, the method of forming a concavo-convex pattern on a molded body and transferring the hot stamp foil is because the object to be transferred is a rugged surface, air can easily get into the interface between the molded body and the hot stamp foil, and the quality is significantly impaired. There was a risk of being lost. On the other hand, even if we try a method of attaching metal to a molded product having irregularities on the surface by vapor deposition or the like, the surface is not smooth, so a uniform metal thin film layer cannot be obtained, and a high-quality product with stable color tone is produced. It was difficult.

  An object of the present invention is to solve such problems and to produce a high-quality decorative molded body having a novel design, capable of stably applying a decoration such as a matte metallic tone or a hairline metallic tone. It was made as.

  Then, this invention presses the uneven | corrugated provision tool which has an uneven surface on the surface about the decoration layer fixed to the molded object through the base layer about the manufacturing method of the decorative molded object by which the molded object was decorated. And the manufacturing method of the decorative molded object characterized by forming this decoration layer in an unevenness | corrugation is provided.

  The decorative layer fixed on the molded body via the base layer is pressed with a concave / convex imparting tool having a concave / convex surface, and the decorative layer is formed into a concave / convex surface. Unlike the case, the decorative layer can be formed without being affected by the uneven shape of the adherend surface. Therefore, air is not mixed in when the decorative layer is formed. Moreover, the surface of the base layer is also deformed into irregularities, and a decorative layer is provided following the irregular shape, so that a uniform decorative layer without unevenness or chipping can be formed even if the decorative layer is thin or thick. . And the decoration molded object which has the decoration with a three-dimensional effect can be obtained. Furthermore, it is sufficient if the decorative layer is deformed into a concavo-convex shape, and manufacturing is easy because there is no need to deform the molded body.

  The base layer can be made of a thermoplastic composition, and can be a method for producing a decorative molded body that is heated to press the unevenness imparting tool. Since the base layer is manufactured using a thermoplastic composition, if the decorative layer is heated and pressed with an unevenness imparting tool, the base layer is easily deformed, and the decorative layer attached to the base layer is also easily deformed. For this reason, it is possible to form a decorative molded body that is capable of forming a dense uneven pattern and is excellent in design.

  Moreover, it can also be set as the manufacturing method of the decorative molded body which consists of a soft resin composition for a base layer. Since the base layer is manufactured using the soft resin composition, the base layer is easily deformed without applying an excessive pressing force to the unevenness imparting tool, and the decoration layer attached to the base layer is also easily deformed. For this reason, it is possible to form a decorative molded body that is capable of forming a dense concavo-convex pattern and is excellent in design.

  Furthermore, the present invention provides a decoration for forming a decorative layer composed of a metal thin film layer having a layer thickness of 0.01 μm to 0.1 μm by any one of a vacuum vapor deposition method, a sputtering method, and a physical vapor deposition method including an ion plating method. It can be set as the manufacturing method of a molded object.

  Since the decoration layer made of a metal thin film layer having a layer thickness of 0.01 μm to 0.1 μm is formed by any one of a vacuum deposition method, a sputtering method, and a physical deposition method including an ion plating method, the resulting decoration layer layer The thickness is very thin. However, after forming the decoration layer on the base layer, the unevenness is deformed by the unevenness imparting tool, so that it is possible to obtain a high-quality decorative molded body without causing unevenness or chipping of the metal thin film even if the decoration layer is thin. it can. In addition, since the decoration layer is formed of a metal thin film layer, it is possible to give a decoration such as a dull metallic tone or a hairline metallic tone, not just a glossy metallic tone.

  The decorative layer can also be formed by transfer. Since the decorative layer is formed by transfer, the decorative molded body can be easily formed. Moreover, since the metal thin film layer and coloring material layer which are formed in advance are transferred to form a decoration layer, a decoration layer having a stable quality can be obtained.

  And this invention forms a concavo-convex surface on a resin film by moving in one direction while pressing the resin film using a concavo-convex applicator having random concavo-convex on the surface, and this resin film is used as another concavo-convex applicator. It can be set as the manufacturing method of the decorative molded body which presses the said decoration layer and gives a hairline-like decoration.

  Since the unevenness imparting tool having random irregularities on the surface is used to move the resin film in one direction while pressing the resin film to form the uneven surface on the resin film, a hairline-shaped unevenness imparting tool can be easily made. Furthermore, since the decoration layer is pressed using this unevenness imparting tool, hairline decoration can be applied without damaging the decoration layer.

  According to the method for producing a decorative molded body of the present invention, it is easy to create a decorative molded body decorated with a novel design that visually recognizes a matte metallic tone, a hairline metallic tone, etc. with high quality without air intrusion. Can be manufactured.

  Specific embodiments of the present invention will be described in detail with reference to the drawings. As shown in FIG. 1, the decorative molded body 11 has a decorative layer 14 on a molded body 12 with a base layer 13 interposed therebetween, and further has a layer structure in which a protective layer 15 covers the surface of the decorative layer 14 and is molded. On the back surface of the body 12, a display unit 16 representing characters and symbols is provided. In FIG. 1, a cross section of a key top for a push button switch of a mobile phone is schematically shown as the decorative molded body 11.

  FIG. 2 shows a manufacturing method using a hot stamp foil as an example of a manufacturing method of the decorative molded body 11 step by step. First, a molded body 12 is obtained by molding a transparent hard resin into a predetermined shape in advance. The display unit 16 is printed on the back surface of the obtained molded body 12. Next, the hot-melt adhesive which becomes the base layer 13 is applied to the hot stamping foil which has the metal thin film layer and becomes the decorative layer 14, and is transferred to the back surface of the molded body 11 (FIG. 2A). And in order to form an uneven | corrugated pattern in the decoration layer 14, the uneven | corrugated provision tool 18 which has formed the uneven | corrugated pattern in the surface previously is pressed on the back surface of the molded object 12 in which the decoration layer 14 was provided on predetermined conditions. (FIG. 2 (B)). In this way, the decorative layer 14 deformed into a concavo-convex shape is obtained (FIG. 2C). Thereafter, the protective layer 15 is applied and formed on the surface of the decorative layer 14 to obtain the decorative molded body 11 having the layer structure shown in FIG.

  The molded body 12 is a base of the decorative molded body 11, and an optimal material is appropriately selected according to the application of the decorative molded body 11. For example, a hard resin such as a polycarbonate resin, an acrylic resin, or an ABS resin is used for a key top for a push button switch or a cover member for a liquid crystal panel. In addition, in the case of an electronic device casing, a metal plate may be used in addition to the hard resin. Such a molded body 12 is preferably molded in advance according to the application, but can be molded into a predetermined shape after being decorated.

  The decoration layer 14 is a layer that embodies the decoration applied to the molded body 12, and is a layer that forms various color tones. When applying metal-like decoration, a transfer layer obtained by a hot stamp foil having a metal thin film layer, a metal layer obtained by a method such as vapor deposition, sputtering, or ion plating, a metal layer obtained by chemical plating It is formed of a colored layer obtained from an ink or paint obtained by kneading a metal powder with a resin. Moreover, when giving colors other than a metallic tone, it forms with the colored layer obtained by printing, coating, transfer, etc.

  The layer thickness of the decoration layer 14 is 0.01 μm to 1 μm, preferably 0.01 μm to 0.1 μm in the case of a metal thin film layer formed by physical or chemical plating, and when transferring a hot stamp foil or the like. Is 1 μm to 10 μm, preferably 3 μm to 5 μm. When using a metallic ink, it is 1 μm to 20 μm, preferably 2 μm to 10 μm. As described above, it is possible to make the layer thickness suitable for the method of forming the decorative layer 14.

  The base layer 13 is a layer that not only fixes the decorative layer 14 to the molded body 12 but also has a function as a base of the uneven pattern of the decorative layer 14. The base layer 13 is preferably selected based on a combination with the decorative layer 14. In the case of transfer of a hot stamp foil or the like, an adhesive constituting a part thereof may function as the base layer 13 as it is, or a hot melt adhesive provided separately from the hot stamp foil or the like is used as the base layer 13. In some cases. On the other hand, when the decoration layer 14 is provided by physical plating such as vapor deposition, a resin to which vapor-deposited metal easily adheres is used as the base layer 13, and when chemical plating is used, a resin to which plating is applied is formed as the base layer 13.

  The layer thickness of the base layer 13 differs depending on the target decoration, but in order to form a three-dimensional deep uneven pattern, a thickness that allows the depth is required. Specifically, the thickness may be about 1 μm to 20 μm, preferably about 2 μm to 10 μm. Since the base layer 13 is formed with a predetermined thickness, even if the decorative layer 14 attached to the base layer 13 has a width from a thin layer to a thick layer, the base layer 13 is deformed to become uneven later. Sometimes the decorative layer 14 is not cut. Therefore, decoration can be performed without being affected by the type and thickness of the decorative layer 14. And since the base layer 13 exists, it can decorate, without deform | transforming the molded object 12. FIG.

  The side of the base layer 13 that is in contact with the decorative layer 14 forms an uneven pattern together with the decorative layer 14. Therefore, when the unevenness imparting tool 18 is heated and pressed to form an uneven pattern on the decorative layer 14, the base layer 13 is preferably made of a thermoplastic composition that is softened by heating. Examples of such a resin include a polyvinyl acetate resin, a urethane resin, an ester resin, an ethylene copolymer resin, an amide resin, and a thermoplastic elastomer. The heating temperature is 100 ° C to 250 ° C, preferably 150 ° C to 210 ° C. Further, instead of heating the unevenness imparting tool 18, it is possible to press in a temperature atmosphere in which the thermoplastic composition is softened or immediately after taking out from such a temperature atmosphere. On the other hand, when pressing at normal temperature, it is preferable to use a soft thermoplastic composition. More specifically, a soft resin such as a polyvinyl acetate resin or a thermoplastic elastomer can be used.

  The unevenness imparting tool 18 has an uneven pattern formed on the surface, and can be manufactured using a hard resin such as PET, metal, wood, or the like. The entire unevenness imparting tool 18 may be made of the same material, or the uneven pattern portion may be formed of a different material. In any case, it is only necessary that the concavo-convex pattern is made of a hard resin like PET and has a hardness equal to or higher than that of the resin material forming the base layer 13 at the time of molding.

  In order to make the decorative molded body 11 a matte metallic tone, an unevenness imparting tool 18 having a surface that has been subjected to a rough surface treatment so as to be a random uneven surface is used. The surface roughness (meaning the maximum height, the same applies hereinafter) of the unevenness imparting tool 18 is 10 μm to 20 μm for a fine matte state, and the surface roughness 30 μm for a rough matte state. The thickness is about 35 μm.

  In addition, there are the following three methods for making the hairline metallic tone that emits a metallic color in the shape of a hairline that looks like parallel streaks shown in FIG. First, a method of forming the decoration layer 14 in a hairline shape by moving the unevenness imparting tool 18 in one direction while pressing the surface of the decoration layer 14 using the unevenness imparting tool 18 subjected to random anterior surface treatment. . Secondly, the same unevenness imparting tool 18 as in the first method is used, but instead of pressing the surface of the decorative layer 14, the unevenness imparting tool 18 is moved in one direction while pressing the surface of the PET film, and the PET film surface Is formed into a hairline shape, this PET film is used as another unevenness imparting tool 18, and the decorative layer 14 is pressed with the hairline-shaped PET film. And thirdly, there is a method of forming by simply pressing the decoration layer 14 using an unevenness imparting tool 18 having an uneven pattern composed of parallel mountain lines L as shown in FIG. In the first method, the decorative layer 14 may be damaged. However, the second method has an advantage that the decorative layer 14 is less painful because the hairline-shaped uneven surface is formed on the PET film.

  Here, if the surface roughness is fine, the hairline metal tone is glossy, and if the surface roughness is rough, the hairline metal tone is matte, so the surface roughness is appropriately 0.001 μm to 10 μm according to the desired gloss state. You can choose between degrees. In addition to this, an uneven pattern corresponding to various patterns including a lattice pattern and a geometric pattern is formed, and the decorative layer 14 formed of a shape and a pattern corresponding to the uneven pattern by pressing the decorative layer 14. Can be formed (FIGS. 5 and 6). Note that the decoration layer 14 does not deform all of its surfaces, and for example, in order to make the display unit 16 stand out, it is possible to leave the portion around the display unit 16 undeformed (FIG. 7).

  The protective layer 15 is formed so as to cover the decorative layer 14 and protects the decorative layer 14 from abrasion and dirt. A resin ink or the like is printed or applied on the surface of the decorative layer 14 after the uneven pattern is formed.

  The decorative molded body 11 formed in this way has a novel design with a three-dimensionally visible decoration such as a hairline metallic tone, a matte metallic tone and the like, unlike a decoration having a simple metallic luster. This is a decorative molded body 11.

  The above embodiment is an example applied to a key top for a pushbutton switch. However, the embodiment can be used for a casing of a mobile phone, a cover member for a liquid crystal panel, and other decorative molded bodies. Further, the decorative layer 14 may be provided on the front surface instead of the back surface of the molded body 12.

Example 1 A molded body (11) was prepared by molding a transparent polycarbonate resin into the shape of a key top for a pushbutton switch. A display layer (16) representing the number “1” is printed on the flat back surface of the molded body (11), and a colorless and transparent PVC film is used on the back surface of the molded body (11) including the display layer (16). The base layer (13) was printed to a thickness of 4 μm. Next, an aluminum hot stamp foil having a thickness of 4 μm was transferred to form a decoration layer (14). Thereafter, an unevenness imparting tool in which an uneven pattern formed by forming parallel mountain lines (L) (the width (w) of the mountain lines is 10 μm and the height (h) of the mountains is 10 μm) is provided on the surface of the polyethylene terephthalate film. (18) was prepared, and the unevenness imparting tool (18) was pressed against the decorative layer (14) at room temperature to deform the decorative layer (14) into unevenness. Then, a decorative layer (11) serving as a key top for a pushbutton switch was manufactured by forming a protective layer (15) with resin ink on the surface of the decorative layer (14).

  If the resulting decorative molded body (11) is mixed with extremely small air, the molded body (12) and the base layer (13) are used despite the fact that air is very noticeable. It was a high-quality decorative molded body with no air entrainment at the interface. Moreover, it was a decorative molded body (11) having a hairline metallic tone.

Example 2 ; In place of the unevenness imparting tool (18) used in Example 1, an unevenness imparting tool (18) made of a polyethylene terephthalate film whose surface roughness was 10 μm was prepared, and a decorative layer (14) This unevenness imparting tool (18) was pressed and moved in the horizontal direction at room temperature to deform the decorative layer (14). Otherwise, the decorative molded body (11) was produced in the same manner as in Example 1. The decorated decorative body (11) thus obtained was visually recognized as a matte hairline metal tone without air entrainment.

Example 3 In place of the unevenness imparting tool (18) used in Example 1, an unevenness imparting tool (18) in which a sandpaper of No. 60 was fixed to a flat surface was used. A decorative molded body (11) was produced. The obtained decorative molded body (11) was visually recognized as a dull metallic tone.

Example 4 ; After forming the display layer (16) on the molded body (11) used in Example 1 in the same manner as in Example 1, the base layer (13) made of a urethane resin colored in green is printed and formed. The thickness was 5 μm. Thereafter, a decorative layer (14) made of an aluminum metal thin film having a layer thickness of 0.03 μm was formed by vacuum deposition. Then, using a concavo-convex imparting tool (18) in which a concavo-convex pattern (the depth of the valley portion is 2 μm) is formed on a brick-like pattern, the decorative layer (14) is pressed by heating to 190 ° C. (14) was deformed. A protective layer (15) was provided on the surface of the deformed decorative layer (14) in the same manner as in Example 1. In this way, a decorative molded body (11) to be a key top for a push button switch was manufactured.

  The obtained decorative molded body (11) does not cause chipping or unevenness even when it is subjected to uneven deformation, even though the decorative layer (14) has a very thin metal thin film layer formed by vacuum deposition. It was a high-quality decorative molded body. Moreover, it was a decorative molded body (11) for visually recognizing a three-dimensional brick pattern having a green metallic tone.

The schematic cross section of the decorative molded body of the present invention. Schematic of the manufacturing process of the decorative molded body of the present invention. The schematic diagram showing the surface shape of an unevenness | corrugation provision tool. The top view of the decoration molded object of this invention. The top view of another decoration molded object of this invention. The top view of another decoration molded object of this invention. The top view of another decoration molded object of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Decorative molded body 12 Molded body 13 Base layer 14 Decoration layer 15 Protective layer 16 Display part 18 Concavity and convexity giving tool L Mountain line w Mountain line width h Mountain line height

Claims (6)

In the method for producing a decorative molded body in which a metal-like decorative layer formed with metal-like unevenness is fixed to the surface of the molded body through a resin base layer, and metal-like decoration is applied,
Rigid surface with a rough surface on the surface of a decorative molded body with a metallic decorative layer consisting of a hot stamp foil of 1 μm to 10 μm fixed to the surface of the molded body through a resin base layer of 1 μm to 20 μm. A method for producing a decorative molded body, comprising pressing an unevenness imparting tool made of a resin to form the metallic decoration layer in an unevenness. Using an unevenness imparting tool having random unevenness on the surface, the resin film is moved in one direction while being pressed to provide an uneven surface on the resin film, and this resin film is formed as another unevenness imparting tool. The manufacturing method of the decorative molded body of Claim 1 which presses the said decoration layer using the uneven | corrugated provision tool of Claim 1 as an uneven | corrugated provision tool which consists of hard resin of Claim 1, and gives a hairline-like decoration. The manufacturing method of the decorative molded body of Claim 1 or Claim 2 which forms a resin base layer with a soft thermoplastic composition, and presses with the uneven | corrugated provision tool which consists of the said hard resin at normal temperature. The method for producing a decorative molded body according to any one of claims 1 to 3, wherein a surface roughness of the surface of the unevenness imparting tool made of the hard resin is 0.001 µm to 10 µm. The method for producing a decorative molded body according to any one of claims 1 to 4, wherein the hard resin forming the unevenness imparting tool made of the hard resin is polyethylene terephthalate. The method for producing a decorative molded body according to any one of claims 1 to 5, wherein the molded body is any one of a push button switch, a housing, and a cover member used in an electric / electronic device.

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