JP2010042610A - Method of manufacturing transfer sheet, and resin molded article - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a transfer sheet having a transfer layer in which a minute concavo-convex part is formed, and a resin molded article manufactured by using the transfer sheet. <P>SOLUTION: The transfer sheet 20 includes a minute concavo-convex part 6 on a part of or the whole surface of a base sheet 1, and a transfer layer 10, e.g. a metal thin film layer or a metal oxide layer 5 is formed on a convex part 2 of the minute concavo-convex part 6. In the method of manufacturing the transfer sheet 20, after the minute concavo-convex part 6 of a nano level to a submicron level is formed by a heat nanoimprint method or a room temperature nanoimprint method on the surface of the base sheet 1 or a releasing layer 3, the transfer layer 10 is formed on the minute concavo-convex part 6. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a technique for forming minute irregularities on the surface of a transfer layer of an injection-molded simultaneous transfer product, and is characterized by a nanoimprint method.

Conventionally, as a method of providing minute irregularities on the surface of the transfer layer of the injection-molded simultaneous transfer product, after incorporating the extender pigment (matting agent) having a particle diameter of about several μm into the release layer, the release layer surface is roughened. There was a method of providing a transfer layer.
JP-A-62-174189

  However, when an extender pigment (matting agent) is included to provide fine irregularities on the surface of the transfer layer, there is a problem in that the irregularities vary in size due to variations in particle size and orientation. Further, when the particle size is reduced, extender pigment (matting agent) is buried in the release layer, and there is a problem that unevenness is not formed on a part of the transfer layer surface. For this reason, this method has a problem that it can be applied only to a design such as matte, in which the size of the unevenness may be on the micron level and may vary somewhat.

  Therefore, the present inventors form minute irregularities by the nanoimprinting method as shown below, thereby causing minute irregularities that cannot be confirmed visually from the submicron level to the nano level on the transfer layer surface of the injection molded simultaneous transfer product. Invented a method of providing minute irregularities.

  That is, the present invention is a method for producing a transfer sheet, in which fine irregularities of nano-level to submicron level are formed on the surface of a base sheet by a thermal nanoimprint method, and then a transfer layer is provided on the fine irregularities. Alternatively, a transfer sheet in which a release layer is provided on the surface of the base sheet, and after forming nano-level to sub-micron level micro unevenness on the release layer by a thermal nanoimprint method, a transfer layer is provided on the micro uneven surface It may be a manufacturing method. Alternatively, it may be a transfer sheet manufacturing method in which minute irregularities of nano-level to sub-micron level are formed on the surface of the base sheet by room temperature nanoimprinting, and then a transfer layer is provided on the minute irregularities. Alternatively, a transfer sheet in which a release layer is provided on the surface of the base sheet, nano-level to sub-micron level irregularities are formed on the release layer by a room temperature nanoimprint method, and then a transfer layer is provided on the minute irregularities It may be a manufacturing method.

  Further, the present invention provides a transfer sheet having a nano-imprint method on the surface of the substrate sheet, forming minute irregularities of nano to sub-micron level, irradiating with ionizing radiation, and then providing a transfer layer on the minute irregularities. It is a manufacturing method. Further, the present invention provides a release layer on the surface of the base sheet, and forms nano-level to sub-micron level irregularities on the release layer by the nanoimprint method. It may be a transfer sheet manufacturing method in which a transfer layer is provided on unevenness.

  Further, the present invention may also be a transfer sheet manufacturing method in which a part or all of the transfer layer is composed of a metal thin film layer or a metal oxide layer. Further, the present invention may be a resin molded product provided with a transfer layer having minute irregularities on the surface by thermal transfer or simultaneous molding transfer method using the transfer sheet described above.

  In the method for producing a transfer sheet of the present invention, a minute unevenness is provided on a part or all of the surface of the substrate sheet by a thermal nanoimprint method or a room temperature nanoimprint method, and a transfer layer is formed on the minute unevenness. It is characterized by. Alternatively, a release layer is formed on the substrate sheet, and a minute unevenness is provided on a part or all of the surface of the release layer by a thermal nanoimprint method or a room temperature nanoimprint method, and a transfer layer is formed on the minute unevenness. It is formed. According to the present invention, it is possible to obtain a transfer layer in which minute unevenness that cannot be visually confirmed from the submicron level to the nano level is formed. Therefore, it is possible to obtain a resin molded product having surface properties with excellent performance such as tactile sensation, antireflection, super water repellency, and security hologram.

  In addition, the method for producing a transfer sheet according to the present invention includes a nanoimprint method, in which fine irregularities are provided on a part or all of the surface of a base sheet or a release layer, and then a transfer layer is provided on the fine irregularities. The ionizing radiation is irradiated to the minute unevenness. Therefore, since minute irregularities excellent in wear resistance and chemical resistance are formed, there is an effect that the irregular shape can be maintained even if an organic solvent having a high polarity is used for the transfer layer, for example.

  In the transfer sheet manufacturing method of the present invention, a part or all of the transfer layer is formed of a metal thin film layer. That is, in the present invention, the material of the metal thin film layer is Al, Cu, Cr, Ni, Au, Ag, or the like. Therefore, it is possible to select a metal material that is resistant to corrosion, and the effect of corrosion can be reduced by increasing the thickness, so it is also applicable to products that may be exposed to high-temperature and high-humidity environments. There is an effect that can be done. Furthermore, since the material is originally a conductive or electromagnetic shielding material, there is an effect that the conductive portion and the insulating portion or the electromagnetic shielding portion and the radio wave transmitting portion can be obtained as a design having the same appearance.

  In the transfer sheet of the present invention, a part or all of the transfer layer is made of a metal oxide layer. That is, in the present invention, the material of the metal oxide layer is tin oxide, indium oxide, indium tin oxide, zinc oxide, magnesium oxide, gallium oxide, aluminum oxide, or the like. Therefore, the transparent conductive film can be partially insulated by forming them on the uneven portions formed partially, and a transparent conductive pattern can be formed without going through a process such as etching. There is.

  Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view showing a schematic configuration of a transfer sheet according to the first embodiment of the present invention (1), and (2) to (4) are transfer sheets shown in (1). It is the general | schematic process drawing which showed this manufacturing method. FIG. 2 is a sectional view showing a schematic configuration of a transfer sheet according to the second embodiment of the present invention (1), and (2) to (4) are transfer sheets shown in (1). It is the general | schematic process drawing which showed this manufacturing method. FIG. 3 is a schematic process diagram showing another method for manufacturing the transfer sheet shown in FIG. FIG. 4 is a schematic process diagram showing a method of manufacturing a resin molded product using the transfer sheet shown in FIG. FIG. 5 is a schematic process diagram showing another method of manufacturing a resin molded product using the transfer sheet shown in FIG. 1 or FIG.

  Referring to FIG. 1 (1), a transfer sheet 20 of the present invention has minute irregularities 6 provided on a part or all of the surface of a base sheet 1, and a metal is formed on the convexes 2 of the minute irregularities 6. A transfer layer 10 such as a thin film layer or a metal oxide layer 5 is formed. Alternatively, referring to (1) of FIG. 2, the release layer 3 is formed on the base sheet 1, and minute unevenness 6 is provided on a part or all of the surface of the release layer 3. A transfer layer 10 such as a metal thin film layer or a metal oxide layer 5 is formed on the projections 2 of the irregularities 6.

  As the substrate sheet 1, polycarbonate resin, cycloolefin resin, polypropylene resin, polyethylene resin, amide resin, polyester resin, acrylic resin, polyvinyl chloride resin resin sheet, glassine paper, coated paper Cellulose-based sheets such as cellophane, or composites of the above respective sheets can be used.

  The material of the release layer 3 is polycarbonate resin, cycloolefin resin, chlorinated polypropylene resin, vinyl resin, amide resin, polyester resin, acrylic resin, polyurethane resin, acetal resin, melamine resin. Examples thereof include resins such as resins, cellulose resins, and alkyd resins, and may contain various additives and colorants composed of pigments or dyes of appropriate colors as necessary. In addition, you may form layers, such as a pattern layer, an anchor layer, a mold release layer, and a peeling layer, between the mold release layer 3 and the base sheet 1. FIG.

  As a method for forming the release 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 used. It can also be adopted. Then, the following minute irregularities 6 are formed on the surface of the base sheet 1 or the release layer 3.

Examples of minute irregularities 6 of submicron nano level protrusion 2 is made of island pattern size of 0.01μm ² ~4μm ^2, the width of the recess 9 in 10 to 2000 nm, the aspect of the recess 9 The ratio (that is, the depth of the concave portion 9 with respect to the width of the concave portion 9) is 0.01 to 5. When the metal thin film layer or the metal oxide layer 5 is formed on such a minute convex portion 2, the metal thin film layer or the metal oxide layer 5 can be formed in an island pattern having a desired shape and size, so that it is stable. There is an effect that insulation performance and radio wave transmission performance can be obtained.

  Further, since the insulation performance and radio wave transmission performance can be maintained without being affected by the thickness of the metal thin film layer or metal oxide layer, there is an effect that can be applied to a design that requires light shielding properties such as an illuminated display window. Furthermore, if the width of the concave portions of the fine irregularities is 10 to 2000 nm and the aspect ratio of the concave portions is 0.01 to 5, the presence of the concave portions cannot be visually confirmed, and a smooth surface having no fine irregularities. There is an effect that an appearance similar to that of the metal thin film layer or metal oxide layer can be obtained.

In addition, it is very difficult to make the convex part 2 into an island pattern having a size of less than 0.01 μm ² , and even if it can be realized, the metal luster of the metal thin film layer 5 may be lowered. There is. On the other hand, if an island-shaped pattern having a size of 4 μm ² or more is formed, the metal thin film layer or the metal oxide layer 5 forms a conductive pattern of that size, and the insulation and radio wave permeability are reduced. On the other hand, when the width of the concave portion 9 is larger than 2000 nm, it becomes apparent that the concave portion 9 is formed, which is not preferable in appearance. On the other hand, it is very difficult to make the width of the recess 9 less than 10 nm with the current technical level, and even if it can be realized, the tunnel current may flow if the metal thin film layer or the metal oxide layer 5 is formed. is there. If the aspect ratio of the concave portion 9 is less than 0.01, it is difficult to provide the metal thin film layer or the metal oxide layer 5 on the convex portion 2 of the minute irregularities 6. On the other hand, it is very difficult to set the aspect ratio of the recess 9 to 5 or more with the above-mentioned width with the current technical level.

  In addition, the concave and convex portions 6 are formed such that the concave portions 9 are formed in an island structure, the width of the convex portions 2 is 20 to 2000 nm, and the aspect ratio of the convex portions 2 is 0.2 to 2.5. The metal thin film layer or the metal oxide layer 5 can be formed on the concave portion 9, and the metal thin film layer or the metal oxide layer 5 can be formed in an island pattern having a desired shape and size. Note that the metal thin film layer or the metal oxide layer 5 may be formed in both the island-shaped structure portion and the gap portion between the island and the island. The metal thin film layer or the metal oxide layer 5 formed in the gap portion may be removed.

  As a removal method when the convex portion is formed in an island structure, only the metal thin film layer or the metal oxide layer 5 formed in the island structure portion is covered and protected with a resist by a general-purpose gravure printing method or the like. Thereafter, there is a method in which the metal thin film layer or the metal oxide layer 5 formed in the gap between the islands is etched away by dipping in an etching solution. Moreover, the convex part or recessed part formed in the island-like structure may be covered with an etching resist, and the corresponding concave part or convex part may be removed by etching or the like.

Further, by forming the metal thin film layer 5 in a lattice pattern opposite to the island pattern, even if it is a material such as Al, Cu, Cr, Ni, Au, Ag, etc., it is transparent or nearly transparent. A transfer layer 10 made of a conductive pattern can also be formed. It In addition, the fine irregularities, protrusions regular quadrangular pyramid or diameter of ² square size 0.1 to 0.5 [mu] m is if the conical pattern of 0.1 to 0.5 [mu] m ² [Phi size, to impart an antireflection function Is also possible.

  Referring to (2) to (4) in FIG. 1 and (2) to (4) in FIG. 2, the method of forming minute irregularities 6 from the nano level to the submicron level is based on the nanoimprint method. The nanoimprinting method of the present invention is a processing method in which a stamper 13 provided with minute protrusions is pressed against the surface of the substrate sheet 1 or the release layer 3 to form minute irregularities 6 on the surface of the substrate sheet 1 or the release layer 3. It is. Examples of the nanoimprint method used in the present invention include a thermal nanoimprint method and a room temperature nanoimprint method.

  In the thermal nanoimprint method, a stamper 13 made of nickel electroforming is produced from a mother die drawn by cutting, laser machining, electron beam machining, etc., and placed on the base sheet 1 or the release layer 3. The stamper 13 is pressed under high temperature and high pressure, and after cooling, the stamper 13 is removed from the base sheet 1 or the release layer 3 to form a minute recess 6 in the base sheet 1 or the release layer 3. The temperature at the time of pressing is set to be higher than the softening point of the base sheet 1 or the release layer 3 and lower than the thermal decomposition temperature, and the pressure is generally set to several MPa to several tens of MPa. After pressing for several seconds to several minutes, the substrate sheet 1 or the release layer 3 is left to stand until the surface of the base sheet 1 or the release layer 3 is below the softening point by rapid cooling or natural cooling. 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.

  The room temperature nanoimprint method uses a sol-gel material (for example, Toray Dow Corning HSQ) against the substrate sheet 1 or the release layer 3 of the thermal nanoimprint method, and presses the substrate sheet 1 or In this method, minute irregularities 6 are formed on the release layer 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.

  After forming the minute irregularities 6 as described above, the transfer layer 10 is formed on the minute irregularities 6. For example, as shown in FIG. 1 (1) and FIG. 1 (2), a metal thin film layer or a metal oxide layer 5 is formed on the convex portion 2, and the adhesive layer 8 is formed so as to cover the entire surface. Form. Thus, the transfer sheet 20 is manufactured.

  In addition, with reference to (1) to (3) in FIG. 3, in both the thermal nanoimprint method and the room temperature nanoimprint method, the ionizing radiation 50 is irradiated after imprinting and before the transfer layer 10 is provided on the minute unevenness 6. Also good. When pressing must be performed under high temperature and high pressure in the thermal nanoimprint method, the dimensional accuracy may decrease, the pressing time and the cooling time may increase, and productivity may decrease. This is because when a high organic solvent is used, the shape of the minute irregularities 6 may be destroyed by the organic solvent.

  That is, by forming fine irregularities 6 on the substrate sheet 1 or the release layer 3 by room temperature nanoimprinting or low temperature thermal nanoimprinting, the cooling process is shortened or unnecessary, improving the throughput and improving the dimensional accuracy. Make improvements. Then, the ionizing radiation 50 is irradiated onto the minute irregularities 6 to accelerate the curing polymerization reaction, and the wear resistance and chemical resistance of the base sheet 1 or the release layer 3 are improved to withstand a highly polar organic solvent. To get.

  When it is assumed that the ionizing radiation 50 is irradiated as described above, the base sheet 1 or the release layer 3 is cured and polymerized when the stamper 13 is pressed to form fine irregularities 6 rather than the aforementioned materials. It is preferable to select a material that is in an unreacted state and in a tack-free state and that accelerates the curing polymerization reaction by irradiation with ionizing radiation 50. By nanoimprinting in an unreacted state of curing polymerization, fine irregularities 6 can be easily formed at room temperature or low temperature, and it is easy to handle because it is in a tack-free state. This is because, by being promoted, excellent wear resistance and chemical resistance can be obtained.

  Examples of such a material include a (meth) acrylic equivalent of 100 to 300 g / eq, a hydroxyl value of 20 to 500, a polymer having a weight average molecular weight of 5,000 to 50,000 and a polyfunctional isocyanate, or a melting point of 40 ° C. or higher and a molecular weight. Examples thereof include a mixture of an active energy ray-curable resin having a molecular weight of 5,000 to 100,000 and a photoinitiator polymer, or a glycidyl (meth) acrylate polymer obtained by addition reaction of an α, β-unsaturated monocarboxylic acid. It is done.

Note that the state of unreacted curing polymerization does not mean that no curing polymerization has occurred, but does not mean that the main curing polymerization reaction has occurred, and includes cases in which a slight curing polymerization reaction has occurred. The tack-free state refers to a state in which the material of the base sheet 1 or the release layer 3 is not visually attached to the finger even when the outermost surface is touched with a finger at a pressure of 1 g weight / cm ² . Examples of the ionizing radiation 50 include radio waves, visible light, ultraviolet rays, infrared rays, X-rays, gamma rays, particle beams, electron beams, and the like.

  In addition to the metal thin film layer or the metal oxide layer 5, the transfer layer 10 may be provided with a peeling layer, a pattern layer, an adhesive layer, and an anchor layer. The anchor layer is a resin layer for improving the adhesion between each layer, and usually a two-component curable urethane resin, a thermosetting resin such as a melamine type or an epoxy type is often used. In the case of being provided between the pattern layer and the pattern layer, a vinyl resin or an acrylic resin of the same type as the pattern layer is used for affinity with the release layer. As a method for forming the anchor layer, there are a coating method such as a gravure coating method, a roll coating method and a comma coating method, and a printing method such as a gravure printing method and a screen printing method.

  The adhesive layer adheres each of the above layers to the surface of the molded product 7. The adhesive layer is formed on the part to be adhered on the release layer or the picture layer. That is, when the part to be bonded is entirely, the adhesive layer is formed on the entire surface. Further, when the part to be bonded is partial, an adhesive layer is partially formed. As the adhesive layer, a heat-sensitive or pressure-sensitive resin suitable for the material of the molded product 7 is appropriately used. For example, when the material of the molded product 7 is a polyacrylic resin, a polyacrylic resin may be used. When the material of the molded product 7 is a polyphenylene oxide / polystyrene resin, a polycarbonate resin, a styrene copolymer resin, or a polystyrene blend resin, a polyacrylic resin, a polystyrene resin having an affinity for these resins, A polyamide resin or the like may be used. Furthermore, when the material of the molded product 7 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 5 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 addition, when a peeling layer and a pattern layer have sufficient adhesiveness with respect to the molded article 7, it is not necessary to provide an adhesive layer.

  The configuration of the transfer sheet 20 is not limited to the above-described mode. For example, the transfer sheet 20 is used only for painting a metal thin film layer or a metal oxide layer by utilizing the ground pattern and transparency of the molded product 7. When the transfer sheet 20 is used, the pattern layer may be omitted.

Hereinafter, the manufacturing method of the resin molded product 30 will be described using the transfer sheet 20 having the above-described layer configuration.
Referring to (1) and (2) of FIG. 4, first, the transfer sheet 20 is disposed on the resin portion 70 with the adhesive layer side down. Next, using a transfer machine such as a heat transfer rubber-like elastic body 8 such as a roll transfer machine equipped with silicon rubber or an up-down transfer machine, conditions of a temperature of about 80 to 260 ° C. and a pressure of about 50 to 200 kg / m ² were set. Heat or / and pressure is applied from the base sheet 1 side of the transfer sheet 20 through the heat-resistant rubber-like elastic body 8. By doing so, the adhesive layer adheres to the surface of the resin portion 70. Next, when the base sheet 1 is peeled off after cooling, peeling occurs at the interface between the base sheet 1 and the release layer (if a release layer is provided on the base sheet 1, the release layer is peeled off when the base sheet 1 is peeled off). And the peeling layer occurs at the boundary surface), and the resin molded product 30 is obtained.

  The resin portion 70 may be transparent, translucent, or opaque, and may or may not be colored. Examples of the material of the resin portion 70 include general-purpose resins such as polystyrene resin, polyolefin resin, ABS resin, AS resin, and AN resin. General engineering resins such as polyphenylene oxide / polystyrene resins, polycarbonate resins, polyacetal resins, acrylic resins, polycarbonate-modified polyphenylene ether resins, polyethylene terephthalate resins, polybutylene terephthalate resins, ultrahigh molecular weight polyethylene resins, and polysulfone resins, Super engineering resins such as polyphenylene sulfide resins, polyphenylene oxide resins, polyacrylate 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.

  Next, a method for manufacturing the resin molded product 30 using the transfer sheet 20 described above and having the transfer layer transferred simultaneously with the injection molding will be described.

  Referring to (1) to (3) in FIG. 5, first, a transfer mold 10 is formed inside a molding die composed of a movable mold 31 and a fixed mold 32, that is, made of a light transmissive material. The transfer sheet 20 is fed so that the base sheet 1 is in contact with the fixed mold 32. At this time, the single transfer sheet 20 may be fed one by one, or a necessary portion of the long transfer sheet 20 may be intermittently fed. When the long transfer sheet 20 is used, it is preferable to use a feeding device having a positioning mechanism so that the registration of the pattern layer of the transfer sheet 20 and the molding die coincide. Further, when the transfer sheet 20 is intermittently fed, if the transfer sheet 20 is fixed by the movable mold 31 and the fixed mold 32 after the position of the transfer sheet 20 is detected by a sensor, the transfer sheet is always at the same position. This is convenient because 20 can be fixed and the pattern layer is not displaced. After closing the molding die, the molten resin is injected and filled into the die from the gate provided in the fixed die 32, and simultaneously with the formation of the resin portion 70, the transfer layer 10 is adhered to the surface thereof. After cooling the resin part 70, the molding die is opened and the resin molded product 30 with the transfer layer 10 formed on the surface is taken out. In this way, the resin molded product 30 is manufactured. When a long transfer sheet 20 is used, the transfer layer 20 is peeled off from the base sheet 1 at the same time as the mold is opened. If the transfer sheet 20 is a single wafer, the base sheet 1 is formed by removing the molded product from the mold. The transfer layer 20 peels from the base sheet 1 by peeling from the product.

A polyester resin film having a thickness of 38 μm was used as the base sheet, and an acrylic resin release agent was applied to the thickness of 1 μm by gravure printing on the base sheet to form a release layer. Unevenness was formed. Fine irregularities, protrusions made of a regular quadrangular pyramid pyramidal took orderly pattern of 0.3 [mu] m ² square size, the aspect ratio of the convex portion is formed by thermal nanoimprint method using a roll at 1.5. The temperature at the time of pressing was set to 100 ° C. and the pressure was set to 9 MPa. After pressing at a speed of 1 m / min, natural cooling was performed. A UV curable hard coat material was formed on the entire surface with a solid thickness of 6 μm by reverse coating as a release layer. The release layer was crosslinked and cured by irradiation with ultraviolet rays (ultraviolet irradiation conditions were 120 w / cm, 6 lamps, lamp height 10 cm, belt speed 15 m / min), and a vinyl resin as a pattern layer on the release layer, An acrylic ink was formed as an adhesive layer by a gravure printing method to obtain a transfer material. The obtained release layer was an excellent protective film having hard coat properties and antireflection properties.

An acrylic resin film having a thickness of 75 μm was used as the base sheet, and minute irregularities were formed on the base sheet. The minute irregularities were formed by an island-like pattern having a convex portion having a size of 2 μm ² , the width of the concave portion was 800 nm, the aspect ratio of the concave portion was 1.5, and formed by a thermal nanoimprint method using a roll. The temperature at the time of pressing was set to 90 ° C. and the pressure was set to 5 MPa. After pressing at a speed of 1 m / min, natural cooling was performed. A metal thin film layer made of Al was formed on the formed micro-projections by a vacuum deposition method. The obtained metal thin film layer had island-like structure insulation and radio wave transmission. A transfer material was obtained by gravure printing using an acrylic ink as an adhesive layer.

An acrylic resin film having a thickness of 75 μm was used as the base sheet, and minute irregularities were formed on the base sheet. The minute irregularities were formed by an island-like pattern having a convex portion having a size of 2 μm ² , the width of the concave portion was 800 nm, the aspect ratio of the concave portion was 1.5, and formed by a thermal nanoimprint method using a roll. The temperature at the time of pressing was set to 90 ° C. and the pressure was set to 5 MPa. After pressing at a speed of 1 m / min, natural cooling was performed. A metal thin film layer made of Al was formed on the formed minute recesses by a vacuum deposition method. The obtained metal thin film layer was comparable to a transparent conductive film having a lattice-like structure and translucency and conductivity. A transfer material was obtained by gravure printing using an acrylic ink as an adhesive layer.

A polyester resin film having a thickness of 38 μm was used as the base sheet, and an acrylic resin release agent was applied onto the base sheet to a thickness of 1 μm by a gravure printing method to form a release layer. Minute irregularities were formed on the part. The minute irregularities were formed by an island-like pattern having a convex portion of 2 μm ² in size, the width of the concave portion 9 was 800 nm, the aspect ratio of the concave portion was 1.5, and thermal nanoimprinting using a roll. The temperature at the time of pressing was set to 100 ° C. and the pressure was set to 9 MPa. After pressing at a speed of 1 m / min, natural cooling was performed. A metal oxide layer made of indium tin oxide was formed by sputtering on part of the microprojections of the mold release layer and on the mold release layer that did not form microscopic irregularities. The obtained metal oxide layer exhibited insulating properties on minute irregularities, and was a transparent conductive pattern film having conductivity on a release layer that did not form minute irregularities. Then, a transfer material was obtained by gravure printing using acrylic ink as an adhesive layer thereon.

A polyester resin film having a thickness of 38 μm is used as a base sheet, and the base sheet is composed of a polymer having a (meth) acryl equivalent average of 200 g / eq, a hydroxyl value average of 200, and a weight average molecular weight of 5,000 to 50,000 and a polyfunctional isocyanate. After the release layer was formed on the entire surface with a thickness of 1 μm, minute irregularities were formed on the entire surface of the release layer. Fine irregularities, protrusions and a positive pyramid pyramids took orderly pattern of 0.3 [mu] m ² square size, the aspect ratio of the convex portion is 1.7. The minute irregularities were formed by a room temperature nanoimprint method using a roll at a speed of 1 m / min with a pressure set to 8 MPa. Thereafter, the entire release layer was irradiated with ultraviolet rays having a strength of 300 MJ / cm ² to cure the release layer. A metal oxide layer made of indium tin oxide was formed on the release layer by sputtering. The obtained metal oxide layer becomes an excellent functional film having both transparent conductivity and an antireflection function. Then, a transfer material was obtained by gravure printing using acrylic ink as an adhesive layer thereon.

Minute irregularities were formed on a portion of a 38 μm thick substrate sheet made of a mixture of a urethane acrylate resin having a melting point of 60 ° C. and a molecular weight of 10,000 to 50,000 and an isocyanate polymerization initiator. The minute irregularities are composed of a pattern in which a large number of irregular cone-shaped pyramids having a pitch of 10 to 70 μm and a depth of about 1 to 3 μm are arranged in an orderly manner. The minute irregularities were formed by a low temperature thermal nanoimprint method using a roll at a speed of 1 m / min with the temperature during pressing set to 40 ° C. and the pressure set to 25 MPa. Thereafter, the substrate sheet was cured by irradiating the entire substrate sheet with ultraviolet rays having a strength of 500 MJ / cm ² . A pattern layer was formed by a gravure printing method with a colored ink on the partial micro-projections and on a base sheet on which micro-recesses were not formed. The pattern layer formed on the minute protrusions exhibits a matte-like high-quality design, and the pattern layer on the base sheet that does not form minute irregularities exhibits a high-glossy and high-quality design. Then, a transfer material was obtained by gravure printing with acrylic ink as an adhesive layer thereon.

The transfer material of Example 1 to Example 6 was transferred to the surface of the molded product using the molding simultaneous transfer method, and then the base sheet was peeled off to obtain a molded simultaneous transfer product. The molding conditions were a resin temperature of 240 ° C., a mold temperature of 55 ° C., and a resin pressure of about 300 kg / cm ² . The molded part was made of acrylic resin as the material of the resin part, and formed into a tray shape of 95 mm in length, 65 mm in width, rise of 4.5 mm, and R2.5 mm in the corner part.

(1) is a cross-sectional view showing a schematic configuration of a transfer sheet according to the first embodiment of the present invention, and (2) to (4) show the transfer sheet manufacturing method shown in (1). It is the shown schematic process drawing. (1) is a cross-sectional view showing a schematic configuration of a transfer sheet according to a second embodiment of the present invention, and (2) to (4) are the transfer sheet manufacturing method shown in (1). It is the shown schematic process drawing. FIG. 4 is a schematic process diagram illustrating another method for manufacturing the transfer sheet illustrated in FIG. 2. FIG. 3 is a schematic process diagram showing a method for producing a resin molded product using the transfer sheet shown in FIG. 2. FIG. 3 is a schematic process diagram showing another method for producing a resin molded product using the transfer sheet shown in FIG. 1 or 2.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Base sheet 2 Convex part 3 Release layer 5 Metal thin film layer or metal oxide layer 6 Minute unevenness 8 Adhesive layer 9 Concave part 10 Transfer layer 13 Stamper 20 Transfer sheet 30 Resin molded product 50 Ionizing radiation 70 Resin part

Claims (8)

  A method for manufacturing a transfer sheet, comprising forming nano-level to sub-micron level irregularities on a substrate sheet surface by a thermal nanoimprint method, and then providing a transfer layer on the minute irregularities.   Producing a transfer sheet in which a release layer is provided on the surface of the base sheet, and nano- to sub-micron irregularities are formed on the release layer by thermal nanoimprinting, and then a transfer layer is provided on the irregularities. Method.   A method for producing a transfer sheet, comprising forming nano-level to sub-micron level irregularities on a substrate sheet surface by a room temperature nanoimprint method, and then providing a transfer layer on the minute irregularities.   Producing a transfer sheet in which a release layer is provided on the surface of the base sheet, and after forming minute irregularities of nano to sub-micron levels on the release layer by a room temperature nanoimprint method, a transfer layer is provided on the minute irregularities. Method.   A method for producing a transfer sheet, comprising forming nano-level to sub-micron level micro unevenness on the surface of a substrate sheet by the nanoimprint method, irradiating with ionizing radiation, and then providing a transfer layer on the micro unevenness.   A release layer is provided on the surface of the base sheet, nano-imprint method is used to form nano-level to sub-micron level micro unevenness on the release layer, and after irradiation with ionizing radiation, a transfer layer is formed on the micro uneven surface. A method for producing a transfer sheet.   The manufacturing method of the transfer sheet in any one of Claims 1-6 in which a part or all of the said transfer layer consists of a metal thin film layer or a metal oxide layer.   A resin molded product in which fine irregularities are formed on the surface by transferring the transfer layer using the transfer sheet according to any one of claims 1 to 7 by thermal transfer or simultaneous molding transfer method.

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