JP4683392B2 - Transfer sheet for transparent cover parts and transparent cover parts - Google Patents

Description

  The present invention relates to a transfer foil, a molded simultaneous transfer foil, and a transparent cover part obtained by transferring them, particularly displays for mobile phone terminals, video cameras, digital cameras, portable information terminals, etc. that require high-quality display performance. The present invention relates to a transfer sheet for a transparent cover molded body and a transparent cover part for manufacturing a part or a camera lens cover part.

  In recent years, portable devices such as mobile phone terminals, video cameras, and portable small personal computers have become widespread and are generally used. Most of these portable devices are provided with a display display unit, and a user of the device obtains a lot of information from characters and images displayed on the display display unit.

  Mobile phone terminals and PDAs with cameras are also widely distributed, and injection molded products are often used as transparent cover molded bodies for protecting the lenses of the cameras.

  Cover parts for displays and lenses such as cellular phones and portable information terminals are sometimes made by transferring a transfer film by thermal transfer or simultaneous molding transfer. According to these methods, the decoration and the hard coat on the surface of the cover part can be added in one step, and in the case of simultaneous molding transfer, they can be added to the three-dimensional curved surface. The transfer film used at this time has a structure in which a transfer layer is formed on the surface of the base sheet. The transfer layer is a surface protective layer that is peeled off from the base film and positioned on the outermost surface of the molded body at the time of transfer, a pattern ink layer such as a pattern in the transfer layer, and an adhesive layer for bonding with the resin molded body. Each has a laminated structure.

  Here, the surface protective layers of conventional transfer foils and simultaneous molding transfer foils generally contain extender pigments in order to provide hard coat properties and blocking resistance. Hard coat refers to scratch resistance and abrasion resistance, and blocking refers to contact between the coated surface and the back surface of the substrate when the surface is coated and the substrate is wound up. This is a phenomenon in which the layer provided on the coating surface peels off and adheres.

Since this phenomenon is caused by the close contact between the coating surface and the back surface of the substrate, an extender having a large particle size of 5 μm or more (for example, 1 to 10 μm) is added to the coating surface to form irregularities on the surface. A technique for preventing the blocking by roughening is disclosed. For example, in JP-A-2000-109682 (Patent Document 1), by putting a lubricant such as polyethylene wax and paraffin wax in the surface protective layer, the surface can be roughened and blocking can be made difficult to occur. It is disclosed that when the amount of the lubricant is less than 0.5% by weight, the surface cannot be sufficiently roughened and the effect of preventing blocking is reduced.
JP 2000-109682 A

  The particle diameter of these lubricants is generally a few μm, and if this particle is added in an amount of 0.5% by weight or more in order to prevent blocking, haze (the appearance of an unclear cloudy appearance inside or on the surface of the transparent body) ) Becomes larger. Therefore, when this transfer sheet is transferred to a transparent window cover of a display or a lens cover of a camera as a molded product, the transparent portion becomes cloudy, so that the performance of these products requiring transparency is deteriorated.

  Moreover, when the particle diameter contained in the transfer film is large, irregularities are formed on the surface of the molded product. Irregularities on the surface of the transparent window cover cause refraction and scattering of light, and cause deterioration of the quality of the transparent resin molded product such as glare of the transparent window cover, flare of the lens cover of the camera, and resolution reduction.

  Therefore, the technical problem to be solved by the present invention is to provide a transparent cover component transfer sheet and a transparent cover component using the transfer sheet, which can prevent blocking, and at the same time, can solve the problems of haze and glare. Is to provide.

  In order to solve the above technical problem, the present invention provides a transfer sheet having the following configuration.

According to the first aspect of the present invention, the substrate has a base film and a transfer layer formed on the surface of the base film, and the transfer layer is formed on the surface of the transparent cover molded body that is a molded resin body. A transfer sheet for a transparent cover molded body that is peeled off from a film and transferred,
The transfer layer is provided with a transparent protective layer that peels off from the base film after transfer and forms the outermost surface of the transparent cover molded body,
The transparent protective layer is composed of an acrylic resin, a urethane resin, a melamine resin, an epoxy resin, or a mixed resin of two or more thereof, an average particle diameter of 1 μm or less, and a refractive index of 1.42 to 1. A transfer sheet for a transparent cover molded article is provided, which comprises 10 to 70 wt% of an extender pigment as No. 52 in terms of solid content.

  According to a second aspect of the present invention, there is provided the transfer sheet for a transparent cover molded body according to the first aspect, wherein the extender pigment has a refractive index substantially equal to that of the resin forming the transparent protective layer. provide.

  According to a third aspect of the present invention, the refractive index of the extender pigment is a difference of 0.03 or less from the refractive index of the resin forming the transparent protective layer. Provide a sheet.

  According to a fourth aspect of the present invention, the surface protective layer is made of an active energy ray-curable resin, and the transfer sheet for a transparent cover molded body according to any one of the first to third aspects, I will provide a.

  According to a fifth aspect of the present invention, there is provided the transfer sheet for a transparent cover molded body according to any one of the first to fourth aspects, wherein the extender pigment is composed of silica-based reactive fine particles. provide.

  According to the first aspect of the present invention, the acrylic protective resin, urethane-based resin, melamine-based resin, epoxy-based resin, or a mixed resin of two or more of these resins that have a transparent protective layer has adhesiveness. Blocking can be prevented by mixing 10 to 70% by weight of extender pigments which are transparent particles having an average particle diameter of 1 μm or less. If the extender pigment is less than 10% by weight, sufficient hard coat properties of the transparent protective layer cannot be ensured, and if it exceeds 70% by weight, the transparency and stretchability of the transparent protective layer are impaired. Further, the extender has a refractive index of 1.42 to 1.52 and a refractive index close to that of the resin constituting the transparent protective layer, and thus haze can be prevented. Furthermore, since scattering tends to occur when the particles are larger than the visible light wavelength region, the extender pigment can be made as small as 1 μm or less to prevent scattering. In addition, in the said structure, it is preferable that 1 micrometer or more particle | grains are not contained in a surface protective layer, or even if it contains, it is 1 weight% or less.

  In the second and third aspects of the present invention, when the difference between the refractive index of the extender pigment and the refractive index of the resin of the coating film to which the extender pigment is added (approximately 0.03 or more), light scattering increases, Haze is likely to occur. The difference in refraction between the resin constituting the transparent protective layer and the material constituting the extender pigment is preferably 0.03 or less. If the refractive index is more than that, the haze value becomes high and white cloudiness occurs.

  According to the 4th aspect of this invention, hard coat property can be made higher by using the active energy ray hardening material hardened | cured with an ultraviolet-ray or an electron beam as resin which comprises a transparent protective layer.

  According to the fifth aspect of the present invention, since the silica sol has a refractive index close to that of the resin constituting the transparent protective layer, haze can be prevented. In addition, particles having a size of 1 μm or less can be easily and inexpensively obtained, and can be uniformly dispersed in the transparent protective layer in that the dispersibility is good.

  Hereinafter, a transfer film according to an embodiment of the present invention will be described with reference to the drawings. First, the basic configuration of a simultaneous molding and painting apparatus using the transfer sheet according to the present embodiment will be described.

  As shown in FIG. 1, a molding simultaneous painting apparatus 110 includes a movable mold 1 attached to a movable platen 61, a fixed mold 2 attached to a fixed platen 62, and a molding space defined between the two molds. Are provided with an injection nozzle 65 for injecting molten resin.

  In this embodiment, the fixed platen 62 is fixed to the gantry 66, and the movable plate 61 is guided by the tie bar 64 fixed to the fixed platen 62 so as to be detachable from the fixed platen 62.

  By moving the movable platen 61, the parting surface of the movable mold 1 and the parting surface of the movable mold 1 are pressed against each other, and the second cavity 58 of the movable mold 1 and the first of the movable mold 1 are moved. A mold closed state in which a molding space is defined by the cavity 28 and a mold open state in which the parting surfaces of both molds are separated from each other are obtained.

  Further, basically, a mold space is formed by the two molds using the movable mold 1 and the movable mold 1. For example, an intermediate mold sandwiched between both molds to form a mold space. Additional members such as molds can also be used.

  The movable plate 61 is provided with a sheet feeding device 67 and a sheet winding device 68. The sheet feeding device 67 and the sheet winding device 68 move the transfer sheet 100 in the vertical direction (vertical direction) with respect to the first cavity 28 of the movable mold 1. The transfer sheet 100 is moved in the vertical direction so as to be separated from and parallel to the parting surface of the movable mold 1.

  The attachment positions of the sheet feeding device and the sheet winding device on the movable mold side and the fixed mold side are not limited to those shown in FIG. The sheet feeding device 67 may be provided at the lower portion of the movable plate 61, and the sheet winding device 68 may be provided at the upper portion of the movable plate 61. Alternatively, the sheet feeding device 67 and the sheet winding device 68 on the movable mold side may be attached to the left and right sides, and the sheet feeding device and the sheet winding device on the fixed mold side may be attached to the upper part or the lower part of the fixed platen 62. . Further, the sheet feeding device and the sheet winding device may be directly attached to the gantry.

  That is, the transfer sheet 100 is arranged to face the mold parting surface (parting surface of the movable mold 1 or parting surface of the movable mold 1) before performing simultaneous painting. In addition, the transfer sheet 100 may be configured to be movable.

  Next, the configuration of the transfer sheet will be described. FIG. 2 shows an external configuration of the transfer sheet according to the present embodiment. The transfer sheet according to the present embodiment is sent out so as to move on the parting surface of the movable mold from the roll state, and after being simultaneously formed with a painting, it is wound up in a roll shape by a sheet winding device. .

  As shown in FIG. 2, the transfer sheet 100 is provided with patterns 31 at intervals in the longitudinal direction. As shown in FIG. 3, the transfer sheet 100 has a structure in which a base film 35, a release layer 38, and a transfer layer 32 are laminated. The transfer layer 32 is provided with a transparent protective layer 34 and a pattern ink layer 31a constituting the pattern 31 thereon. Further, an adhesive layer 33 is provided on the design ink layer 31a, and contacts and adheres to the molten resin at the time of simultaneous painting, and the transfer layer 32 interfaces the lower surface 34a of the transparent protective layer 34 with the interface. It peels from the mold release layer 38.

  At the time of simultaneous molding, after the transfer sheet is sandwiched in a molding die, the resin is injected and filled in the cavity and cooled to obtain a resin molded product, and at the same time, the transfer sheet 100 is adhered to the surface. Then, the base film 35 is peeled off, and the transfer layer 32 is transferred to the surface of the resin molded product for decoration.

  The material of the base film 35 includes diols such as ethylene glycol, trimethylene glycol, tetramethylene glycol and bisphenol, terephthalic acid, isophthalic acid, phthalic acid, diphenic acid, adipic acid, naphthalenedicarboxylic acid, eicoic acid and dimer acid. A resin mainly composed of polyester having an ester group in the main chain, obtained by polycondensation with a dicarboxylic acid represented by, for example, is used. Specific examples include polyethylene terephthalate, polytetramethylene terephthalate, polyethylene-p-oxybenzoate, poly-1,4-cyclohexylene dimethylene terephthalate, and polyethylene-2,6-naphthalate. These polyesters may be homopolymers or copolymers, and examples of the copolymer component include diol components such as diethylene glycol, neopentyl glycol, and polyalkylene glycol, adipic acid, phthalic acid, isophthalic acid, 2 And dicarboxylic acid components such as 6-naphthalenedicarboxylic acid. Of these materials, those mainly composed of polyethylene terephthalate, polybutylene terephthalate, and polybutylene terephthalate are preferable. Particularly preferred is polyethylene terephthalate having excellent tensile strength and heat resistance. The base film 35 may be transparent or translucent when the pattern layer 31a provided on one surface is visible through the other surface. Although the base film 35 may be colored, in order to make use of the color of the picture layer 31a itself, a colorless film is preferable.

  The thickness D of the base film 35 is generally 0.025 mm to 0.10 mm and more preferably 0.030 mm to 0.050 mm when used for simultaneous injection molding. This is because if it is thinner than 0.025 mm, the film 100 for simultaneous injection-molding is easily broken due to the high heat and injection pressure of the molding resin. On the other hand, when the thickness exceeds 0.10 mm, the rigidity increases and it becomes difficult to use as a printing substrate when printing the pattern layer 31a and the like.

  The release layer 38 is entirely formed on the base film 35 in order to improve the peelability of the transfer layer from the base film 35. However, when the peelability of the transfer layer 32 from the base film 35 is good, the transfer layer 32 may be provided directly on the base film 35 without providing it. The release layer 38 is released from the transfer layer 32 together with the base film 35 when the base film 35 is peeled off after the simultaneous decorating, but in some cases, an interlayer release occurs, and a part of the release layer 38 is transferred. May remain on the outermost surface. The material of the release layer 38 is acrylic resin, nitrified cotton resin, polyurethane resin, chlorinated rubber resin, vinyl chloride-vinyl acetate copolymer resin, polyamide resin, polyester resin, epoxy resin, polycarbonate. Resin-based resin, olefin-based resin, acrylonitrile butadiene styrene resin-based release agent, and composite release agents thereof can be used. In particular, it is preferably composed of one type of epoxy resin, melamine resin, or urethane resin, or a mixed resin of two or more types.

  The thickness of the release layer 38 is preferably 0.1 to 2.0 μm. As a method for forming the release layer, a coating method such as a roll coating method or a spray coating method, a printing method such as a gravure printing method or a screen printing method is used.

  The transparent protective layer 34 is a layer that becomes the outermost surface when the transfer film 100 is transferred to the transparent cover molded body, and serves as a clear coating as a coated product. The molded resin body may be required to have hard coat properties such as scratch resistance and abrasion resistance, and this property can be imparted to the transparent cover molded body by the transparent protective layer 34.

  As a material for the transparent protective layer 34, an acrylic or methacrylic monomer homopolymer such as polymethyl methacrylate, polyethyl methacrylate, polyethyl acrylate, polybutyl acrylate, or an acrylic copolymer comprising these monomers is used. In addition to resin, melamine resin, acrylic resin, urethane resin, epoxy resin and the like can be used. Specifically, two-component curable resins such as melamine, acrylic melamine, epoxy melamine, alkyd, urethane, acrylic, etc. and a mixture of these, or a combination with a curing agent such as isocyanate, polyester acrylate Polyester methacrylate, epoxy acrylate, epoxy methacrylate, urethane acrylate, urethane methacrylate, polyether acrylate, polyether methacrylate, polyol acrylate, melamine acrylate, melamine methacrylate and other monomers and prepolymers that have ethylenically unsaturated bonds Ultraviolet rays, electron beam curable resins, and the like can be used. When an ultraviolet curable resin is used, a photoinitiator is further added. In this embodiment, polymethyl methacrylate (refractive index 1.5) is used.

  In the transparent protective layer 34, extender pigments 37, which are transparent particles, are dispersed and mixed. The extender pigment 37 is a particle having an average primary particle size of 1 μm or less. The extender pigment 37 is contained in a solid content ratio of 10 to 70% by weight, preferably 20 to 50% by weight. If the extender pigment is less than 10% by weight, the transparent protective layer 34 cannot be provided with a sufficient hard coat property, and if it exceeds 70% by weight, the transparency of the transparent protective layer 34 and the stretchability at the time of molding simultaneous transfer are deteriorated. To do.

  Further, since the extender pigment 37 has a thickness of 1 μm or less, it is possible to prevent glare without forming large irregularities on the surface of the transparent cover molded body during transfer. Further, by using a material having a refractive index close to the refractive index of the resin constituting the transparent protective layer 34 as the extender pigment 37, the transparent protective layer 34 does not become cloudy, and the haze of the transparent cover molded body is increased. Can be small. In this embodiment, silica sol (refractive index: 1.3 to 1.5) having substantially the same refractive index as that of polymethyl methacrylate (refractive index of 1.5) constituting the transparent protective layer 34 is used as an extender, and light Prevents scattering and refraction. In addition, if the size of the extender pigment is larger than the wavelength of visible light, it causes refraction and scattering of light. By using an extender pigment of 1 μm or less, light refraction and scattering are reduced, and Haze can be reduced. That is, the transparent protective layer 34 can prevent blocking by mixing 10 to 70% by weight of a small extender pigment that does not have adhesiveness, and at the same time, can solve the problems of haze and glare.

  Note that silicon, fluorine, styrene, silica, alumina, titanium dioxide, magnesium oxide, zinc oxide, magnesium carbonate, calcium carbonate, or the like can be used as the extender material.

  As a method for forming the transparent protective layer 34, a coating method such as a roll coating method or a spray coating method, a printing method such as a gravure printing method or a screen printing method is used, and an extender pigment 37 is dispersed on the surface of the release layer 38. It is formed by printing the above resin. The thickness of the transparent protective layer is preferably 0.5 to 50 μm. When the film thickness is less than 0.5 μm, there is a problem that sufficient hard coat properties cannot be obtained. When the film thickness is more than 50 μm, it takes time to dry during formation, and cracks occur during transfer.

  The design ink layer 31a is a layer that expresses characters, numbers, figures, symbols, patterns, and the like formed on the surface of the transparent cover molded body. The design ink layer 31a is usually formed on the transparent protective layer 34 by printing. Examples of the material of the design ink layer 31a include acrylic resins, nitrified cotton resins, polyurethane resins, chlorinated rubber resins, vinyl chloride-vinyl acetate copolymer resins, polyamide resins, polyester resins, and epoxy resins. A colored ink containing a resin as a binder and an appropriate color pigment or dye as a colorant may be used. As a method for forming the pattern ink layer 31a, a normal printing method such as an offset printing method, a gravure printing method, a screen printing method, or the like may be used. In particular, the offset marking 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 print layer may be provided entirely or partially depending on the pattern to be expressed.

  The design ink layer 31a may be composed of a metal thin film layer or a combination of a printing layer and a metal thin film layer. The metal thin film layer is for expressing the metallic luster as the design ink layer 31a, and is formed by a vacuum deposition method, a sputtering method, an ion plating method, a plating method, or the like. In this case, a metal such as aluminum, nickel, gold, platinum, chromium, iron, copper, tin, indium, silver, titanium, lead, or zinc, or an alloy or compound thereof is used depending on the metallic luster color to be expressed. As an example of forming a partial metal thin film layer, a solvent-soluble resin layer is formed on a portion that does not require the metal thin film layer, and then a metal thin film is formed on the entire surface, followed by solvent cleaning. There is a method of removing an unnecessary metal thin film together with a solvent-soluble resin layer. A solvent often used in this case is water or an aqueous solution. As another example, there is a method in which a metal thin film is formed on the entire surface, a resist layer is then formed on a portion where the metal thin film is to be left, and etching is performed with acid or alkali to remove the resist layer. . In addition, when providing a metal thin film layer, in order to improve the adhesiveness of another transfer layer and a metal thin film layer, you may provide a front anchor layer and a rear anchor layer. As the material of the front anchor layer and the rear anchor layer, two-component cured urethane resin, thermosetting urethane resin, melamine resin, cellulose ester resin, chlorine-containing rubber resin, chlorine-containing vinyl resin, polyacrylic resin, It is preferable to use an epoxy resin, a vinyl copolymer resin, or the like. 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.

  The film thickness of the pattern ink layer 31a is preferably 0.5 μm to 50 μm. When the film thickness is less than 0.5 μm, there is a problem that sufficient designability cannot be obtained, and when it is more than 50 μm, there is a problem that it is difficult to dry after printing. However, in the case of a metal film layer, 50-1200 micrometers is preferable. This is because if the thickness of the metal film layer is less than 50 μm, there is a problem that a sufficient metallic luster cannot be obtained, and if it is more than 1200 μm, there is a problem that cracks tend to occur.

  The adhesive layer 33 adheres each of the above layers to the surface of the resin molded product. The adhesive layer 33 is formed on a portion to be bonded. That is, when the part to be bonded is the entire surface, the adhesive layer 33 is formed on the entire surface of the design ink layer 31a. When the part to be bonded is partial, the adhesive layer 33 is partially formed on the design ink layer 31a. As the adhesive layer 33, a heat-sensitive or pressure-sensitive resin suitable for the material of the resin molded product is appropriately used. For example, when the material of the resin molded product is a polyacrylic resin, the same polyacrylic resin may be used. In addition, when the material of the resin molded product is a polyphenylene oxide copolymer polystyrene copolymer resin, polycarbonate resin, styrene resin, or polystyrene blend resin, a polyacrylic resin or polystyrene having an affinity for these resins Resin, polyamide resin, etc. may be used. Further, when the material of the resin molded product is a polypropylene resin, chlorinated polyolefin resin, chlorinated ethylene-vinyl acetate copolymer resin, cyclized rubber, and coumarone indene resin can be used.

  The thickness of the adhesive layer 33 is preferably 0.5 to 50 μm. When the film thickness is less than 0.5 μm, there is a problem that sufficient adhesion cannot be obtained, and when it is more than 50 μm, there is a problem that it is difficult to dry after printing. As a method for forming the adhesive layer 33, a printing method such as a gravure coating method, a roll coating method, or a comma coating method, a gravure printing method, a screen printing method, or the like is used. Print from.

  Note that the configuration of the transfer layer 32 is not limited to the above-described embodiment. For example, when a material having excellent adhesion to a resin molded product is used as the material of the design ink layer, the adhesive layer 33 is formed. Can be omitted.

  The extender pigment may be contained not only in the transparent protective layer 34 but also in each of the base film 35 and the transfer layer 32, for example. The extender pigment contained in each layer preferably has the same physical properties as that of the extender pigment contained in the transparent protective layer 34, and the refractive index is 1 μm or less and a value that approximates the refractive index of the resin constituting the transparent protective layer 34. It is preferable to have. Preferably, the extender pigment contained in each layer is mixed in a solid content ratio of 10 to 70% by weight, more preferably 20 to 50% by weight.

  A method for decorating the surface of the transparent cover molded body, which is a resin molded body, by the molding simultaneous transfer method using the transfer sheet 100 described above will be described. 4A to 4C show a schematic resin flow for understanding the resin flow. First, as shown in FIG. 4A, a transfer sheet is fed into a molding simultaneous painting mold composed of a movable mold 1 and a movable mold 1. In this case, in the present embodiment, a necessary portion of the long transfer sheet 100 is intermittently fed, but the transfer material for each leaf may be fed one by one. When the long transfer sheet 100 is used, it is preferable to use a feeding device having a positioning mechanism so that the register 31 of the transfer sheet matches the register of the mold for simultaneous painting.

  Also, when the transfer sheet is intermittently fed, if the transfer sheet is fixed by sandwiching it between the movable mold and the fixed mold after the position of the transfer sheet is detected by the sensor, the transfer sheet is always transferred at the same position. It is convenient because the material can be fixed and the positional shift of the design ink layer does not occur.

  Next, as shown in FIG. 4B, after the mold for simultaneous painting is closed, the molten resin is injected and filled into the cavity from the gate 46 provided on the fixed side mold to form the transfer object. At the same time, the transfer sheet is adhered to the surface. As described above, the transparent protective layer 34 contains extender pigments of 1 μm or less, and large irregularities are not formed on the surface of the transparent cover molded body. Therefore, when the transparent cover molded body is used as a cover member of a liquid crystal display or as a lens cover of a digital camera, glare and flare can be prevented. In cooling the molten resin, a coolant for cooling the cavity is supplied to the cavities of both molds from a cooling water supply device (not shown), and the molten resin can be solidified in a short time by cooling the cavities. Can be shortened.

  Next, as shown in FIG. 4C, after the transparent cover molded body that is the transfer object is cooled, the mold for simultaneous painting is opened and the transparent cover molded body is taken out. Finally, by peeling off the base film 35, a transparent cover molded body in which the transfer layer 32 is transferred onto the surface of the injected molding resin can be obtained.

  FIG. 5 is a view showing an external configuration of a transparent cover molded body molded by the simultaneous molding apparatus of FIG. The transparent cover molded body 90 shown in FIG. 5 is used by being attached to the surface of the casing of the mobile phone terminal. The transparent cover molded body 90 protects the liquid crystal display and the small digital camera.

  As shown in FIG. 5, the transparent cover molded body 90 is a thin transparent resin panel, and is provided with a decorative portion 94 and transparent window portions 91 and 93, and below the transparent window portions 91 and 93. The light can be transmitted to a liquid crystal display, a small digital camera, and the like. As shown in FIG. 6, the decorative portion 94 is a portion where the transfer layer 32 of the transfer sheet 100 described above is transferred to the molding resin 90a and is painted with the pattern ink layer 31a, and the pattern ink layer 31a is formed. The portions of the transfer layer that are not formed are formed as transparent window portions 91 and 93. The transparent protective layer 34 is positioned on the surface of the transfer layer 32, and the hard coat property of the transparent cover molded body 34 is improved.

  As described above, the transparent protective layer 34 of the transfer layer 32 includes the extender pigment 37 of 1 μm or less, and large irregularities are not formed on the surface of the transfer layer 32 during transfer. Therefore, in the transparent window portions 91 and 93 other than the decorative portion 94, the problem of glare or flare caused by surface irregularities does not occur. Further, since the extender pigment is small, no light scattering occurs in the transparent window portions 91 and 93, and the problem of haze does not occur.

  As described above, according to the transfer sheet according to the present embodiment, the extender pigment having a refractive index of 1.42 to 1.52 and having a size of 1 μm or less is solid content ratio in the transparent protective layer. In addition, 10 to 70% by weight is mixed to prevent unevenness on the surface of the transfer film to prevent blocking, and to prevent formation of large unevenness on the surface of the molded body, thereby causing problems such as glare and flare. Can be prevented. Moreover, since the refractive index is close to that of the resin constituting the transparent protective layer, scattering and refraction of transmitted light can be suppressed, and the problem of haze can be prevented.

  In addition, this invention is not limited to the said embodiment, It can implement in another various aspect. In the above embodiment, the transfer sheet has been described as a transfer sheet for simultaneous painting, but for example, the transfer sheet may be transferred to a transparent cover molded body that is a resin molded body that has been previously molded by thermal transfer. May be.

  Moreover, in the said embodiment, although silica sol is used as an extender, it is not limited to this, Acrylic resin, urethane-type resin, melamine-type resin, epoxy-type resin, or these 2 or more types What consists of mixed resin can be used.

It is a figure which shows schematic structure of the simultaneous shaping | molding painting apparatus with which the transfer sheet which concerns on one Embodiment of this invention is used. It is an external appearance perspective view which shows the structure of the decorating film concerning one Embodiment of this invention used in the shaping | molding simultaneous double-sided decorating apparatus of FIG. It is sectional drawing which shows the cross section of the III-III line of FIG. It is a schematic diagram which shows the process of the simultaneous shaping | molding painting in the simultaneous shaping | molding painting apparatus of FIG. It is a schematic diagram which shows the process of the simultaneous shaping | molding painting in the simultaneous shaping | molding painting apparatus of FIG. It is a schematic diagram which shows the process of the simultaneous shaping | molding painting in the simultaneous shaping | molding painting apparatus of FIG. It is a figure which shows the external appearance structure of the cover part for mobile phones manufactured by the shaping | molding simultaneous double-sided decoration apparatus of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Movable side metal mold | die 2 Fixed side metal mold | die 31a Design ink layer 32 Transfer layer 33 Adhesive layer 34 Transparent protective layer 34a Peeling interface 35 Base film 37 Extender pigment 38 Release layer 90 Transparent cover molding 91, 93 Transparent window part 92 Edge 100 Transfer Film 110 Molding Simultaneous Painting Device

Claims (6)

Transparent cover molding having a base film and a transfer layer formed on the surface of the base film, and transferring the transfer layer by peeling the transfer layer from the base film on the surface of a transparent cover molding that is a molded resin body A body transfer sheet,
The transfer layer is provided with a transparent protective layer that peels off from the base film after transfer and forms the outermost surface of the transparent cover molded body,
The transparent protective layer is composed of an acrylic resin, a urethane resin, a melamine resin, an epoxy resin, or a mixed resin of two or more thereof, an average particle diameter of 1 μm or less, and a refractive index of 1.42 to 1. A transfer sheet for a transparent cover molded article, comprising an extender pigment as a solid content ratio of 10 to 70% by weight. The transfer sheet for a transparent cover molded body according to claim 1, wherein the extender pigment has a refractive index equal to that of the resin forming the transparent protective layer.   2. The transfer sheet for a transparent cover molded body according to claim 1, wherein a refractive index of the extender pigment is a difference of 0.03 or less from a refractive index of the resin forming the transparent protective layer. The said transparent protective layer is comprised with active energy ray hardening resin, The transfer sheet for transparent cover molded objects as described in any one of Claim 1 to 3 characterized by the above-mentioned.   The transfer sheet for a transparent cover molded body according to any one of claims 1 to 4, wherein the extender pigment is composed of silica-based reactive fine particles.   A transparent cover part, wherein the transfer layer of the transfer sheet for a transparent cover molded body according to any one of claims 1 to 5 is transferred by thermal transfer or simultaneous molding transfer.

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