JP2010120235A - Transfer foil for in-mold, and three-dimensional molding using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a transfer foil for in-molding and a three-dimensional molding using the same, wherein the transfer foil has a metallic luster hologram of high design characteristics with little de-lamination, whitening and breaking characteristics even in the three-dimensional injection molding. <P>SOLUTION: The transfer foil includes a base material 11, a leasing layer 13, a hard coat layer 14, a printing layer 21, a hologram layer 15, a reflecting metal layer 17 and an adhesive layer 19: provided that the hologram layer 15 is a layer obtained by curing a composition containing (1), (2) and (3) with an ionizing radiation ray; that the hard coat layer 14 is a layer obtained by curing a composition containing resins (1) and (2) with the ionizing radiation ray, wherein (1) and (2) are the same resin to that of the hologram layer 15; and that for the hard coat layer 14 and the hologram layer 15, (a) the coated film is in the state of set-to-touch before curing by the ionizing radiation ray, (b) the breaking extension is 5% or more in 23°C after ionization radiation curing and (c) they have a heat resistance not to whiten when put 1 h under an atmosphere of 150°C in a state of a transfer foil 10 for in-mold transfer. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an in-mold transfer foil, and more specifically, by inserting into a molding die and molding, the followability to a three-dimensional surface of a molded product is good, and a hologram can be transferred without whitening. The present invention relates to a transfer foil for in-mold and a three-dimensional molded product.

  In the present specification, “ratio”, “part”, “%” and the like indicating the composition are based on mass unless otherwise specified, and the “/” mark indicates that they are integrally laminated. “PET” is an abbreviation, synonym, functional expression, common name, or industry term for “polyethylene terephthalate”. “Urethane (meth) acrylate oligomer” is a general term for “urethane acrylate oligomer and urethane methacrylate oligomer”, and “hologram” includes “hologram and those having a light diffractive function such as a diffraction grating”.

  (Main use) The main use of the three-dimensional molded product using the in-mold transfer foil of the present invention is such as equipment main bodies such as daily necessities and daily necessities, containers for food and various articles, electronic equipment and office supplies, etc. A three-dimensional molded product such as a casing, which has a unique design and security on the surface of the three-dimensional molded product, and the shape and contents of the three-dimensional molded product are arbitrary. However, there is no particular limitation as long as it is an application in which a hologram is transferred to the surface of a three-dimensional molded product in order to improve design and security.

(Background Art) Conventionally, since mediums of the above-mentioned use, for example, brand products and high-class products have economic value, they are constantly counterfeited illegally, and various tampering prevention measures have been proposed to improve security. It is illustrated. It is known to transfer a hologram, which is difficult to forge, has excellent security, and has a light diffraction effect, to a medium. On the other hand, on a flat or curved surface of a molded product by injection molding or the like, in-mold injection molding is performed in which a transfer foil such as a hologram is inserted into a mold during molding and the hologram is transferred simultaneously with the injection molding. However, the transfer is limited to a flat surface or a curved surface in one direction. The three-dimensional part is stretched due to the flow of molten high-temperature injection molding resin, and the transfer foil such as a hologram is stretched and wrinkles and tears occur. When the reflective layer is only an aluminum thin film, the original metallic luster becomes white due to expansion and contraction, and the metallic luster is completely lost, and the hologram is also lost. Conventionally, in order to suppress the influence of expansion and contraction to the minimum, it has been necessary to suppress the influence of expansion and contraction to a minimum by attaching or transferring a hologram to a portion with little expansion and contraction, or making a hologram with a small area.
Therefore, in order to further improve the design and security, even in the case of a three-dimensional injection-molded product transferred by an in-mold injection molding method using a transfer foil having a hologram, heat resistance that does not whiten by heat, and a three-dimensional surface There is a need for an in-mold transfer foil having a hologram that follows well and has little cracking or whitening, and a three-dimensional molded product using the same.

(Prior Art) Conventionally, an in-mold labeling type injection molding of a label made of a laminated sheet including a base material, a printing layer, a light diffraction structure layer (corresponding to the hologram layer of the present invention) and a thermoadhesive resin layer There is known a cup-shaped container that is integrally molded by the above-described method (for example, see Patent Document 1). However, the peripheral wall on which the hologram layer is formed is a flat surface and not a solid surface.
In addition, after the decorative transfer layer (including the hologram layer of the present invention) is transferred to the stretchable material, it is transferred to a part of the surface of the three-dimensional molded product body having at least a part of the surface with unevenness or a curved surface by heating and pressing. A surface decoration molded product is known (for example, refer to Patent Document 2). However, there is a drawback that the decorative transfer layer cannot be directly transferred to a molded product.
Furthermore, a transfer film composed of a base film, a protective layer, a metal thin film (corresponding to the hologram layer and the reflective layer of the present invention), and an adhesive layer is produced, and a pair of molds are clamped with the transfer film interposed therebetween, There is known a method for manufacturing a false nail in which a molten resin is injected into the mold and a metal thin film is applied to the surface of the nail body (see, for example, Patent Document 3). However, the artificial nail is a large curved surface in one direction, and the transfer film itself is wound around a plane, which is difficult to say as a three-dimensional solid. Also, the protective layer, metal thin film, and adhesive layer of the transfer film The material is also very general, and there is no description or suggestion about the stretchability of the material, which is the biggest problem in transferring to a three-dimensional object.
Furthermore, the present applicant has also disclosed a method of forming a hologram by previously forming a fine unevenness when forming a three-dimensional molded product, and then providing a reflective layer on the fine uneven surface (for example, (See Patent Documents 4 to 5.) However, in order to form the fine irregularities in advance, a dedicated shaping film for shaping the fine irregularities must be created, and the in-mold molding method using the film is complicated, and the fine irregularities formed There is a problem that a step of providing a reflective layer is required, resulting in high cost.
None of the above Patent Documents 1 to 5 describes or suggests correspondence to the stretchability of the hologram layer.
Furthermore, the present applicant has applied for a transfer foil for in-mold to a three-dimensional molded product in Japanese Patent Application Laid-Open No. 2007-118467. However, although the same resin composition is used for the resin composition of the protective layer (corresponding to the hard coat layer of the present invention) and the hologram layer, there is no printing layer, and cracking distortion due to the three-dimensional surface of the printing layer. There is no mention of prevention.

JP 2005-7647 A JP 2004-58599 A Japanese Patent Laid-Open No. 2003-9941 JP 2004-163482 A JP 2004-284178 A JP 2007-118467 A

  Accordingly, the present invention has been made to solve such problems. The purpose is to use a resin composition of the same resin as the resin composition of the hard coat layer and the hologram layer, so that the elongation at break of the hard coat layer and the hologram layer is the same, the elongation is stable, and peeling between the layers is also possible. In addition, since it is stretched by being entangled between layers or adjacent printed layers and metal reflective layers, even three-dimensional injection-molded products transferred by the in-mold injection molding method, heat resistance that does not whiten by heat, and well follow the three-dimensional surface It is to provide an in-mold transfer foil having a highly designed hologram with little cracking or whitening, and a three-dimensional molded product using the same.

In order to solve the above problems, an in-mold transfer foil according to the invention of claim 1 includes a base material, a release layer, a hard coat layer, a printing layer, a hologram layer, a metal on one surface of the base material. In an in-mold transfer foil provided with a reflective layer and an adhesive layer, the release layer is a melamine resin, and the hologram layer ionizes a composition containing the following (1), (2) and (3): A layer formed by curing with radiation, and the hard coat layer is a layer formed by curing a composition containing (1) of the same resin as the hologram layer and (2) of the same resin with ionizing radiation, and The hard coat layer and the hologram layer are (a) the coating film before ionizing radiation curing is finger-dried, (b) the elongation at break at 23 ° C. after ionizing radiation curing is 5% or more, and (c) the substrate , Release layer, hard coat layer, printing layer, hologram In the in-mold transfer foil provided with a metal reflection layer and an adhesive layer, it has heat resistance that does not whiten even if it is left in an atmosphere at 150 ° C. for 1 hour, and (1) (i) has an isocyanate group in the molecule. Isocyanates having 3 or more, (b) polyfunctional (meth) acrylates having at least one hydroxyl group and at least two (meth) acryloyloxy groups in the molecule, or (c) having at least two hydroxyl groups in the molecule A urethane (meth) acrylate oligomer that is a reaction product of polyhydric alcohols, (2) is one or more selected from urethane (meth) acrylate oligomers having ether units or ester units, and (3) is silicone oil or It is a reactive silicone.
A three-dimensional molded product according to the second aspect of the present invention is a three-dimensional molded product molded by the in-mold injection molding method using the in-mold transfer foil according to the first aspect. The metal reflective layer and the adhesive layer are transferred.

According to the present invention of claim 1, a three-dimensional injection molded product having the same elongation at break of the hard coat layer and the hologram layer, stable elongation, no separation between the layers, and transferred by an in-mold injection molding method. Even if it has heat resistance that does not whiten by heat, it follows the solid surface well, there is no peeling between layers, there is no cracking or distortion of the printed layer, there are few cracks or whitening in the hologram, etc. An in-mold transfer foil capable of transferring a printed hologram is provided.
According to the second aspect of the present invention, there is no peeling between layers, no cracking or distortion of the printed layer, and there is little cracking or whitening in the hologram, and a solid glossy hologram with high-design printing is transferred. A molded article is provided.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a cross-sectional view of an in-mold transfer foil showing one embodiment of the present invention.
FIG. 2 is a cross-sectional view of a three-dimensional molded product transferred using the in-mold transfer foil of the present invention.

  (In-mold transfer foil) As shown in FIG. 1, the in-mold transfer foil 10 of the present invention comprises a base material 11, a release layer 13, a hard coat layer 14, and a primer layer on one surface of the base material. 23 (if necessary), printing layer 21, primer layer 23 (if necessary), hologram layer 15, metal reflection layer 17 and adhesive layer 19, the release layer 13, hard coat layer 14 and hologram layer 15 is made of a specific material. The hard coat layer 14 and the hologram layer 15 are made of the same resin composition, and a peelable silicone oil or reactive silicone is added only to the hologram layer 15.

By specifying the structure of the present invention, the hard coat layer 14 and the hologram layer 15 and the material, and using the resin composition of the same resin as the resin composition of the hard coat layer 14 and the hologram layer 15, The breaking elongation of the hologram layer 15 can be made the same.
That is, the hard coat layer 14 and the hologram layer 15 are (a) the coating film before ionizing radiation curing is finger-dried, (b) the elongation at break at 23 ° C. after ionizing radiation curing is 5% or more, and (c) The substrate 11, release layer 13, hard coat layer 14, print layer 21, hologram layer 15, metal reflection layer 17, and adhesive layer 19 are provided in an in-mold transfer foil 10 state and left in a 150 ° C. atmosphere for 1 hour. Even if it has heat resistance which does not whiten. In this way, since the elongation is stable and there is no peeling between layers, and the layers are stretched by the printed layer 21 or the metal reflective layer 17 adjacent to each other, the three-dimensional injection molded product transferred by the in-mold injection molding method. However, it is possible to obtain a hologram with high heat resistance that does not whiten by heat and a high design property that follows a solid surface well and has few cracks and whitening.

  The in-mold transfer foil 10 of the present invention is shown in FIG. 2 as a three-dimensional molded product 100 in which a hologram layer is transferred to a three-dimensional molded product by an in-mold injection molding method. In FIG. 2, the three-dimensional molded product is drawn on a plane for convenience of drawing, but it is a three-dimensional solid shape and is a three-dimensional molded product transferred to a three-dimensional surface.

  (In-mold injection molding method) First, the in-mold injection molding method is (1) a step of preparing an in-mold transfer foil 10 and (2) the in-mold transfer foil 10 into an injection mold. (3) A resin is injection-molded and brought into intimate contact with the injection-molding mold, whereby the hard coat layer 14 and primer layer 23 (if necessary) of the in-mold transfer foil 10 are adhered to the surface of the resin. ), Printing layer 21, primer layer 23 (if necessary), hologram layer 15, metal reflection layer 17, and adhesive layer 19, and (4) releasing the mold after cooling and transferring in-mold. A three-dimensional molded product 100 in which a hologram is transferred to a three-dimensional surface can be manufactured by an injection molding method including a step of peeling the base material 11 and the release layer 13 of the foil 10 and taking out the three-dimensional molded product.

  (Substrate) As the substrate 11, various materials can be applied depending on the use as long as the substrate 11 has heat resistance, mechanical strength, mechanical strength to withstand manufacturing, solvent resistance, and the like. For example, polyester resins such as polyethylene terephthalate and polyethylene naphthalate, polyamide resins such as nylon 6, polyolefin resins such as polyethylene, polypropylene and polymethylpentene, vinyl resins such as polyvinyl chloride, polymethyl methacrylate, etc. Examples include acrylic resins, polycarbonate, cellophane, and cellulose films such as cellulose acetate. Preferably, in terms of heat resistance and mechanical strength, polyethylene terephthalate is the most suitable for polyester resin films such as polyethylene terephthalate and polyethylene naphthalate. The thickness of the substrate is usually about 2.5 to 100 μm, but 4 to 50 μm is preferable in terms of transferability.

  The substrate 11 may be a copolymer resin containing these resins as a main component, a mixture (including an alloy), or a laminate including a plurality of layers. The substrate may be a stretched film or an unstretched film, but a film stretched in a uniaxial direction or a biaxial direction is preferable for the purpose of improving the strength. The substrate is used as a film, sheet or board formed of at least one layer of these resins. Prior to application, the substrate is subjected to corona discharge treatment, plasma treatment, ozone treatment, flame treatment, primer (also called an anchor coat, adhesion promoter, or easy adhesive) application treatment, pre-heat treatment, dust removal treatment. Alternatively, easy adhesion treatment such as vapor deposition treatment or alkali treatment may be performed. Moreover, you may add additives, such as a filler, a plasticizer, a coloring agent, and an antistatic agent, as needed.

  (Release layer) The release layer 13 includes a release resin, a resin containing a release agent, and a curable resin that is cross-linked by ionizing radiation. In the present invention, a melamine resin is used. By using the melamine resin, stable releasability is exhibited in combination with the hard coat layer 14 described later.

  The release layer 13 is formed by dispersing or dissolving the resin in a solvent, and applying it to at least one part by a printing or coating method such as roll coating, gravure coating, comma coating, or pre-coating and drying to form a coating film. Form. Further, if necessary, it may be heat-dried or aged at a temperature of 30 ° C. to 120 ° C. The thickness of the release layer 13 is usually about 0.01 μm to 5 μm, preferably about 0.5 μm to 3 μm. The thinner the thickness is, the better. However, when the thickness is 0.1 μm or more, better film formation is obtained and the peeling force is stabilized.

  (Hard Coat Layer and Hologram Layer) The hard coat layer 14 is a layer formed by curing the composition containing (1) and (2) with ionizing radiation, and the hologram layer 15 is composed of the same resin (1). And (2) of the same resin is a resin composition, and a composition obtained by adding (3) to only the hologram layer 15 is cured with ionizing radiation. (1) is (i) an isocyanate having three or more isocyanate groups in the molecule, (b) a polyfunctional (meth) having at least one hydroxyl group and at least two (meth) acryloyloxy groups in the molecule. Urethane (meth) acrylate oligomer that is a reaction product of acrylates or (C) polyhydric alcohols having at least two hydroxyl groups in the molecule, (2) is a urethane (meth) acrylate oligomer having ether units or ester units (3) is a silicone oil or a reactive silicone.

  It is preferable that the resin composition of the hard coat layer 14 and the hologram layer 15 have the same blending ratio.

  (Hard Coat Layer) To the hard coat layer 14, a filler component such as ethylene wax or microsilica may be added to the composition containing (1) and (2) within a range not affecting the function. As the filler, polyethylene wax or microsilica is a filler component. Examples of the polyethylene wax include polyethylene resin particles and beads, and spherical beads are preferable. However, when polyethylene wax is added, the foil cutting property is lowered, so that the addition amount is about 0.01 to 10 parts by mass, preferably 100 parts by mass with respect to the total resin composition of (1) and (2). Is 0.1 to 5 parts by mass. If it is less than this range, burrs will be generated during transfer, and if this range is exceeded, the transparency will deteriorate.

  (Hologram Layer) As the hologram layer 15, the hard coat layer 14 is made of the same resin (1) and the same resin (2) as a resin composition, and the silicone oil or reactive silicone of (3) is applied only to the hologram layer 15. A layer is formed by curing the added composition with ionizing radiation.

  (Silicone) (3) is silicone oil or reactive silicone. Some reactive silicones react with the resin when they are cured with ionizing radiation and are combined and integrated, or some remain. The reactive silicone is a reactive silicone modified by acrylic modification, methacryl modification, epoxy modification, or the like, and the ratio on a mass basis to contain the reactive silicone is the sum of the components (1) and (2). It is about 0.1-10 mass parts with respect to 100 parts, Preferably it is 0.3-5 mass parts. If it is less than this range, peeling from the press stamper is insufficient when the relief is molded, and it may not be molded or may be molded due to close contact, printing, or contamination of the press stamper. Is bad. Further, beyond this range, the adhesiveness of the metal reflection layer to the hologram layer surface is low, and the product value is lost due to peeling between the hologram layer and the metal reflection layer.

  (Resin composition (1)) Among the resin compositions, (1) is (i) an isocyanate having three or more isocyanate groups in the molecule, (b) at least one hydroxyl group in the molecule and (meth) acryloyl. Urethane (meth) acrylate oligomer, which is a reaction product of polyfunctional (meth) acrylates having at least two oxy groups, or (c) polyhydric alcohols having at least two hydroxyl groups in the molecule. It is a urethane-modified acrylate resin having As a preferable urethane (meth) acrylate oligomer, a photocurable resin disclosed in detail in JP-A No. 2001-329031 is preferable. Specific examples include MHX405 varnish (made by The Inktec Co., Ltd., ionizing radiation curable resin product name) and Iupimer UV · V3031 (manufactured by Mitsubishi Chemical Co., Ltd., product name of ionizing radiation curable resin).

(Resin composition (2)) Among the resin compositions, (2) is one or more selected from urethane (meth) acrylate oligomers having ether units or ester units.
By blending urethane (meth) acrylate oligomers having ether units or ester units, it has ionizing radiation curability, and the cured film is super soft, has high elongation, exhibits rubber elasticity, and urethane elastomer. Therefore, the elongation at break at 23 ° C. after ionizing radiation curing can be 5% or more.

  (Ether unit) The urethane (meth) acrylate oligomer having an ether unit may be a heat-resistant oligomer, and examples thereof include trade names of Nippon Synthetic Chemical Co., Ltd .; Shikko 6630B, 7510B, 7630B and the like. As a ratio on the mass basis to contain, it is about 10-30 parts with respect to 100 parts of resin compositions of (1), Preferably it is 15-25 parts. If it is less than this range, the heat resistance is insufficient, and if this range is exceeded, the heat resistance is good, but cracking tends to occur.

(Ester unit) As a urethane (meth) acrylate oligomer having an ester unit, for example, a product name manufactured by Nippon Synthetic Chemical Co., Ltd., purple light UV3520EA and the like can be exemplified.
By using a urethane (meth) acrylate oligomer having an ester unit, the heat resistance without thermal whitening and the flexibility of following a three-dimensional surface and being difficult to crack have been improved. Moreover, when a hologram (fine relief) is molded using a press stamper (embossed plate), it is stuck to the plate without sticking, a hologram layer is taken on the plate, and in-mold injection molding However, there are few burrs and many contradictions can be resolved.

  The urethane (meth) acrylate oligomer having an ester unit is ionizing radiation curable, the cured film is ultra-soft, has high elongation, exhibits rubber elasticity, and has tensile properties similar to urethane elastomers. The elongation at break at 23 ° C. after ionizing radiation curing can be 5% or more. Moreover, since it is excellent in tearing strength and crack resistance, it can be transferred to the surface of a three-dimensional molded article by following the three-dimensional surface even by an in-mold injection molding method. In addition, since it has heat resistance, it does not whiten by heat during in-mold injection molding, so the urethane (meth) acrylate oligomer having an ester unit has a softer film after curing and exhibits rubber elasticity. Moreover, it is preferable because it also has heat resistance.

  As a ratio on a mass basis of containing the urethane (meth) acrylate oligomer having an ester unit, about 10 to 45 parts, preferably 15 to 30 parts, per 100 parts of the urethane (meth) acrylate oligomer of the component (1). It is. Below this range, whitening is likely to occur at high temperatures, and beyond this range, burrs are likely to occur during sticking to the embossed plate and during transfer.

  By forming the hard coat layer 14 into a layer formed by curing a composition containing (1), (2) and, if necessary, a filler with ionizing radiation, the following effects can be obtained. (1) Since the coating film of the hard coat layer 14 in a coated state before ionizing radiation curing is not sticky in a finger dry state and can be wound up without blocking, roll-to-roll processing can be performed.

  By forming the hologram layer 15 into a layer formed by curing a composition containing (1), (2) and (3) with ionizing radiation, the following effects can be obtained. (1) Since the coated film of the hologram layer 15 in a coated state before ionizing radiation curing is not sticky in a finger dry state and can be wound up without blocking, roll-to-roll processing can be performed. (2) Since the moldability is good by including silicone in the hologram layer 15, the relief structure can be easily shaped and cured with ionizing radiation after shaping. In addition, even if the hologram layer 15 is transferred to a three-dimensional molded product having a large expansion and contraction, the hologram layer 15 has a good followability to the expansion and contraction, and transfers a hologram excellent in design with little deterioration in hologram effect such as cracking and whitening to a three-dimensional surface I can do it. The breaking elongation at 23 ° C. after ionizing radiation curing can be 5% or more, preferably 7% or more. If it is less than 5%, it cracks or whitens during expansion and contraction. When it is 7% or more, even if the expansion / contraction ratio is high, it does not crack or whiten during expansion / contraction. (3) In-mold transfer foil provided with a substrate 11, a release layer 13, a hard coat layer 14, a print layer 21, a hologram layer 15, a metal reflective layer 17 and an adhesive layer 19, at 150 ° C., preferably 170 Since it has heat resistance that does not whiten even if it is left in an atmosphere at 1 ° C. for 1 hour, the hologram does not deteriorate even with heat of 150 to 200 ° C., which is the resin temperature in normal injection molding. The hologram image does not deteriorate because it is instantaneous even at 200 ° C. heat. The heat resistance is the same whether or not the adhesive layer 19 is provided. (4) Even in a three-dimensional molded product by the in-mold injection molding method, since the stretchability of the hard coat layer 14 and the hologram layer 15 after curing is the same, the printed layer 21 and the metal reflective layer 17 which are adjacent or adjacent to each other are also uniformly stretched. Therefore, printing and holograms with high design properties can be obtained.

  Furthermore, there are the following effects. (5) The hard coat layer 14 after the transfer becomes the outermost surface layer, and it is free from solvent, mechanical friction, and abrasion even when used in extremely harsh environments, used for a long period of time, and / or repeatedly used many times. Protects prints and holograms and is highly resistant to scratches. (6) Since the hard coat layer 14 is in contact with the release layer 13 using a melamine resin, the hard coat layer 14 has a stable releasability, good foil breakage at the time of transfer, and extremely small occurrence of burrs and the like. Can do.

  (Formation of hard coat layer) The hard coat layer 14 is formed by adding the above-described components (1) and (2) and, if necessary, a photopolymerization initiator, a plasticizer, a stabilizer, a surfactant, After being dispersed or dissolved in a solvent, applied by a known coating method such as roll coating, gravure coating, comma coating, die coating and the like, dried and then reacted (cured) with ionizing radiation. Curing). The thickness of the hard coat layer 14 is usually about 1 μm to 30 μm, preferably about 2 μm to 20 μm. It may be applied several times.

  (Hologram layer formation) The hologram layer 15 is formed by the above components (1), (2), (3) and (4) and, if necessary, a photopolymerization initiator, a plasticizer, a stabilizer, an interface. Add activator, disperse or dissolve in solvent, apply by known coating methods such as roll coating, gravure coating, comma coating, die coating, etc., dry and shape relief, then react with ionizing radiation (curing) ) The thickness of the hologram layer 15 is usually about 1 μm to 30 μm, preferably about 2 μm to 20 μm. It may be applied several times.

  (Hologram) Next, on the surface of the hologram layer 15, a predetermined relief structure such as a hologram that exhibits a light diffraction effect is formed and cured. A hologram is a recording of interference fringes due to the interference of light between object light and reference light in an uneven relief shape, such as a laser reproduction hologram such as a Fresnel hologram, a white light reproduction hologram such as a rainbow hologram, There are color holograms utilizing the above principle, computer generated holograms (CGH), holographic diffraction gratings and the like. The relief shape is a concavo-convex shape, and is not particularly limited, and may have a fine concavo-convex shape such as light diffusion, light scattering, light reflection, light diffraction, etc., such as Fourier transform or lenticular lens. , A light diffraction pattern, and a moth eye. Further, although it does not have a light diffraction function, it may be a hairline pattern, a mat pattern, a line pattern, an interference pattern, or the like that expresses a unique glitter.

  As a method for producing these relief shapes, in addition to holograms and diffraction gratings produced using hologram photographing and recording means, holograms produced using an electron beam drawing device based on optical calculations such as interference and diffraction, A diffraction grating can also be mentioned. Also, a relatively large pattern such as a hairline pattern or a line pattern may be a machine cutting method. These holograms and / or diffraction gratings may be recorded single or multiple, or may be recorded in combination. These original plates can be prepared by known materials and methods, and usually, laser beam interference using a glass plate coated with a photosensitive material, using an electron beam drawing apparatus on a glass plate coated with an electron beam resist material. An electron beam drawing method for patterning can be applied.

  (Relief shaping) The relief shape is shaped (also referred to as replication) on the surface of the hologram layer 15. Hologram shaping can be formed by a known method. For example, when recording diffraction gratings or interference fringes of holograms as reliefs of surface irregularities, a master on which the diffraction gratings or interference fringes are recorded in irregularities is pressed. The concave / convex pattern of the original can be duplicated by using it as a mold (referred to as a stamper) and by superimposing the original on the resin layer and heat-pressing both of them with an appropriate means such as a heating roll.

  (Relief Curing) The hologram layer 15 is irradiated with ionizing radiation during or after embossing with a stamper to cure the ionizing radiation curable resin. The ionizing radiation curable resin becomes an ionizing radiation curable resin (hologram layer 15) when cured (reacted) by irradiation with ionizing radiation after the relief is formed. The ionizing radiation may be classified according to the quantum energy of the electromagnetic wave, but in this specification, all ultraviolet rays (UV-A, UV-B, UV-C), visible light, gamma rays, X-rays, electrons It is defined as including a line. Accordingly, ultraviolet (UV), visible light, gamma rays, X-rays, or electron beams can be applied as ionizing radiation, but ultraviolet (UV) is preferred. An ionizing radiation curable resin that is cured by ionizing radiation may contain a photopolymerization initiator and / or a photopolymerization accelerator in the case of ultraviolet curing, and may not be added in the case of high energy electron beam curing. Can be cured even with thermal energy.

  (Relief pattern) The pattern of the hologram layer 15 is preferably a quasi-continuous pattern. When creating a press mold (referred to as a stamper) for the pseudo continuous pattern, it is only necessary to match a plurality of small relief plates with high accuracy to make the joints inconspicuous, or to fill the joints with resin. In this way, by using a quasi-continuous pattern, the area can be as large as possible, or preferably the entire surface. Further unique design can be improved by synchronizing or matching with any other printed pattern against a large area or entire surface of the hologram pattern.

(Print Layer) The print layer 21 may be a known printing method, and for example, gravure printing, screen printing, flexographic printing, gravure offset printing, inkjet printing, and the like can be applied.
The printing ink includes at least a vehicle and a colorant, and the colorant and the vehicle are not particularly limited, but the vehicle is preferably a synthetic resin system such as a modified alkyd resin, a polyester resin, or a polyamide resin. . If necessary, additives such as a filler, a plasticizer, a dispersant, a lubricant, an antistatic agent, an antioxidant, and an antifungal agent may be added as appropriate.
These printing ink compositions are dispersed and kneaded, and if necessary, the solid content and viscosity are adjusted with a solvent to obtain an ink composition. The ink may be printed by the above printing method, dried, and appropriately formed at a temperature of 30 ° C. to 70 ° C. or irradiated with ionizing radiation (ultraviolet rays, electron beams) as necessary.

  (Primer layer) As shown in FIG. 1, the primer layer 23 is formed between the layers when the printed layer 21 is provided on the hard coat layer 14 surface, when the printed layer 21 surface is provided on the hologram layer 15 surface, or other layers. What is necessary is just to provide as needed in order to improve the adhesive force. The primer layer 23 may be, for example, a polyurethane resin, a polyester resin, a polyamide resin, a polyvinyl chloride resin, an acid-modified polyolefin resin, a (meth) acrylic resin, or a polyethyleneimine compound, depending on the upper and lower layers. An isocyanate compound or the like can be used. The above resin as a main component, dissolved or dispersed in a solvent as appropriate, kneaded thoroughly as needed to prepare a coating agent composition (ink, coating solution), roll coating method, gravure coating method, etc. It may be applied and dried by a known coating method. The primer layer 23 has a thickness of about 0.05 to 10 μm, preferably 0.1 to 5 μm.

  (Metal reflection layer) The metal reflection layer 17 is provided on the metal reflection layer 17 on the relief surface of the hologram layer 15 provided with a predetermined relief structure, thereby enhancing the reflection and / or diffraction effect of the relief. If the reflectance of 15 is higher, it is not particularly limited, and for example, a metal thin film can be applied.

  The metal used for the metal reflection layer 17 is a metal element thin film that has a metallic luster and reflects light, such as Cr, Ni, Ag, Au, and Al, and oxides, sulfides, nitrides, and the like thereof. These thin films may be used alone or in combination. The formation of the light-reflective metal thin film can be obtained by a vacuum thin film method such as a vacuum deposition method, a sputtering method, or an ion plating method so as to have a thickness of about 10 to 2000 nm, preferably 20 to 1000 nm. However, it can also be formed by plating. If the thickness of the metal reflection layer 17 is less than this range, light is transmitted to some extent and the effect is reduced, and if the thickness is more than that, the reflection effect is not changed, which is wasteful in cost.

  (Adhesive layer) An adhesive layer 19 is provided on the surface of the metal reflective layer 17, that is, the surface facing the transfer target. As the material of the adhesive layer 19, a known heat-sensitive adhesive which melts or softens when heated and exhibits an adhesive effect can be applied. Specifically, vinyl chloride vinyl acetate copolymer resin, acrylic resin, polyester Based resins and the like. The material resin is dissolved or dispersed in a solvent, an additive such as a pigment is added as appropriate, and it is applied by a method such as known roll coating or gravure coating and dried to have a thickness of about 0.1 to 30 μm, preferably Is a layer of 0.5 to 10 μm. As the material of the adhesive layer 19, a known heat-sensitive adhesive that melts or softens when heated and exhibits an adhesive effect can be applied. Specifically, a vinyl chloride vinyl acetate copolymer resin, an acrylic resin, a polyester-based resin can be used. Resin etc. are mentioned. The material resin is dissolved or dispersed in a solvent, an additive such as a pigment is added as appropriate, and it is applied and dried by a known method such as roll coating or gravure coating to form a layer having a thickness of 0.1 μm to 30 μm. obtain.

  In addition, the printing layer 21 provided on the conventional hard coat layer 14 and the metal thin film provided on the hologram layer 15 can obtain a metallic luster and design by printing, but they can be whitened or peeled off between layers at high temperature or external force. , Has the disadvantage of When in-mold injection molding is performed on the three-dimensional surface, the planar in-mold transfer foil 10 is stretched along the three-dimensional surface with the injected high-temperature molten resin, and when the printed layer 21 or the metal reflective layer 17 is finely cracked (cracked) ) Occurs, resulting in a decrease in luminance or whitening, making it impossible to observe the hologram.

  When the in-mold transfer foil 10 of the present invention is also molded by the in-mold injection molding method so as to obtain a three-dimensional injection molded product, the hard coat layer 14, the printing layer 21, the hologram layer 15, the metal reflection layer 17, and the adhesive layer 19 is stretched at a high temperature. However, in the in-mold transfer foil 10 of the present invention, since the resin composition of the same resin is used as the resin composition of the hard coat layer 14 and the hologram layer 15, the breaking elongation of the hard coat layer 14 and the hologram layer 15. Are the same. Moreover, the portion where the hard coat layer 14 and the hologram layer 15 are in contact with each other is in a melted state and is almost integrated. The hard coat layer 14, the print layer 21, the hologram layer 15, and the metal reflection layer 17 are also stretched along the three-dimensional surface, but do not peel between the layers and have a large elongation at break of 5% or more. The metal reflection layer 17 is also uniformly stretched so that cracks hardly occur and whitening hardly occurs, and a printing design and a bright hologram can be transferred to a three-dimensional surface. The relief of the hologram is also stretched, but the elongation is such that the light diffraction effect can be maintained, or the fineness may be increased according to the estimated elongation. The substrate 11 is also stretched along the three-dimensional surface, but there is no problem because it has an elongation that can be sufficiently followed.

  Such an effect is obtained by specifying the hard coat layer 14 and the hologram layer 15 of the present invention and using the resin composition of the same resin as the resin composition of the hard coat layer 14 and the hologram layer 15. The breaking elongation of the layer 14 and the hologram layer 15 can be made the same. For this reason, (b) the breaking elongation at 23 ° C. after ionizing radiation curing is 5% or more, and (c) the in-mold transfer foil This can be achieved by having heat resistance that does not cause whitening even when left in an atmosphere at 150 ° C. for 1 hour in 10 states. As a result, the elongation at break of the hard coat layer and the hologram layer are the same, the elongation is stable, there is no separation between the layers, and even a three-dimensional injection molded product transferred by the in-mold injection molding method is heated. Non-whitening heat resistance, well following three-dimensional surface, no peeling between layers, no cracking or distortion of printed layer, few metallic luster holograms with cracking or whitening, high design metallic luster with printing It can be set as the transfer foil 10 for in-mold which can transfer a hologram. By using the in-mold transfer foil 10 of the present invention, there is no delamination between layers, no cracking or distortion of the printed layer, and there is little cracking or whitening of the hologram. A transferred three-dimensional molded product can be obtained.

  (Breaking elongation) The stretchability of the hard coat layer 14 and the hologram layer 15 is expressed by breaking elongation, and the method for measuring the breaking elongation (%) of the layer is a resin after UV curing at 23 ° C. and 55% RH. After the layer was allowed to stand for 24 hours or longer, data processing was performed using the Tensilon multi-function data processing TYPE MP-100 / 200S Ver. Measurement was performed using No. 44. The sample is 10 mm wide, the distance between chucks is 50 mm, the RANGE is 20%, the load is 100 kg, and the tensile speed is 10 mm / min. The elongation with respect to the length was used. In the measurement of the elongation at break of the hologram layer 15, it is difficult to produce only the hologram layer 15 film. Therefore, the 10 μm hologram layer 15 is formed on the 25 μm peeled PET, and then peeled after exposure with a metal halide lamp at an integrated exposure amount of 250 mj. And used as a sample.

  (Heat resistance) As for the heat resistance of the hard coat layer 14 and the hologram layer 15, the substrate 11, the release layer 13, the hard coat layer 14, the print layer 21, the hologram layer 15, the metal reflection layer 17 and the adhesive layer 19 were provided. In the in-mold transfer foil 10 state, it was left in an oven at 150 ° C. to 170 ° C. for 1 hour, and the one that did not crack and / or whiten by visual inspection was regarded as acceptable.

  (In-mold injection molding) Thus, the in-mold transfer foil 10 of the present invention can be prepared. Using the in-mold transfer foil 10, a three-dimensional molded product in which a hologram is transferred to a three-dimensional surface can be manufactured by an in-mold injection molding method. First, (2) the in-mold transfer foil 10 is inserted into an injection mold, and (3) a resin is injection-molded and brought into close contact with the injection mold, and the in-mold transfer foil is attached to the surface of the resin. A known method may be used in which 10 holograms are transferred, (4) after cooling, the mold is released, the base material 11 and the release layer 13 of the in-mold transfer foil are peeled off, and the molded product is taken out. Although a part of the release layer 13 may remain on the hologram layer 15 side, there is no hindrance to peeling, and it is within the scope of the present invention. Also, insert injection molding in which the in-mold transfer foil 10 is continuously inserted into the injection mold by an intermittent method is also preferable.

  (Injection Molded Product with Hologram) In this way, the release layer 13 and the hologram layer 15 are used as the in-mold transfer foil 10 using a specific material, and the in-mold injection molding method is applied to the three-dimensional surface, and the hologram itself is heated. It is possible to manufacture a three-dimensional molded article with a hologram to which a hologram having excellent design properties with excellent heat resistance that does not whiten and good conformity to expansion and contraction, and extremely few cracks and whitening. In addition, the in-mold transfer foil 10 can further improve the unique design characteristics in combination with other arbitrary printed patterns with the hologram pattern as a background.

  (Injection Molded Product) The material of the injection resin is not particularly limited, and may be a known resin that can be an injection resin such as polystyrene, polyethylene terephthalate, polypropylene, and acrylic resin. The shape of the injection-molded product is not particularly limited, and can be applied as long as at least one part has a three-dimensional part. The three-dimensional portion may be a secondary surface or a tertiary surface, and includes a wave shape, a curved surface shape, a polyhedron shape, a circle or a pyramid shape, a spherical shape, and the like, or a combination of these, or a random shape. The three-dimensional molded product by injection molding can be used for equipment main bodies such as daily necessities and daily necessities, containers for foods and various articles, electronic equipment such as mobile phones, and housings such as office supplies.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further in detail, it is not limited to this. In addition, except a solvent, each composition of each layer is a mass part of solid content conversion.

Example 1 Using a PET film having a thickness of 50 μm as the base material 11, a TCM01 medium (Dainippon Ink Co., Ltd., melamine resin product name) coating solution is applied to one surface of the base material 11 by a gravure coating method. After being dried, it was applied to a thickness of 2 μm, dried, and baked at 180 ° C. for 20 seconds to form a release layer 13.
The surface of the release layer 13 is coated with the following ionizing radiation curable resin composition with a gravure reverse coater so that the thickness after drying is 5 μm, and dried at 100 ° C. to obtain an uncured hard coat layer. It was set to 14. In addition, the hologram layer 15 which will be described later was formed, and the hard coat layer 14 was cured together with the hologram layer 15 by irradiating ultraviolet rays using a high-pressure mercury lamp after shaping the relief.
・ <Ionizing radiation curable resin composition of hard coat layer>
MHX405 varnish (trade name, manufactured by The Inktech Co., Ltd.) 80 parts Purple light UV3520EA (manufactured by Nippon Synthetic Chemical Co., Ltd., containing ester units, product name) 20 parts Polyethylene wax (average particle size 5 μm) 4 parts Photopolymerization initiator (Ciba) Manufactured, trade name Irgacure 184) 5 parts solvent (methyl isobutyl ketone: toluene = 1: 1) 300 parts Next, the following primer layer composition was dried on the surface of the uncured hard coat layer 14 with a gravure coater. The primer layer 23 was formed by coating and drying at 100 ° C. to a thickness of 0.5 μm.
・ <Primer layer composition>
Vinyl acetate vinyl chloride copolymer resin 10 parts Polyester resin 10 parts Solvent (toluene: ethyl acetate = 1: 1) 80 parts Next, a known gravure ink using urethane resin as a vehicle is used for the primer layer 23 surface. By using a known gravure printing method, letters and color photographs were printed and dried to form a printing layer 21.
Next, the following primer layer composition was applied to the surface of the printed layer 21 with a gravure coater so that the thickness after drying was 0.5 μm, and dried at 100 ° C. to obtain a primer layer 23.
・ <Primer layer composition>
Vinyl acetate vinyl chloride copolymer resin 10 parts Polyester resin 10 parts Solvent (toluene: ethyl acetate = 1: 1) 80 parts Next, the following ionizing radiation curable resin composition is applied to the surface of the primer layer 23 with a gravure reverse coater. It was coated and dried at 100 ° C. so that the thickness after drying was 2 μm.
・ <Ionizing radiation curable resin composition of hologram layer>
MHX405 varnish (trade name, manufactured by The Inktec Co., Ltd.) 80 parts Purple light UV3520EA (manufactured by Nippon Synthetic Chemical Co., Ltd., containing ester units, product name) 20 parts reactive silicone (trade name: X-22-2445, manufactured by Shin-Etsu Chemical Co., Ltd.) 0.15 parts Photopolymerization initiator (Ciba, trade name Irgacure 184) 5 parts Solvent (methyl isobutyl ketone: toluene = 1: 1) 300 parts Next, the layer is before ionizing radiation curing, and the coating film is The finger was dry. On the layer surface, a press die having a pseudo-continuous pattern duplicated by a 2P method from a diffraction grating by a two-beam interference method is attached to an embossing roller of a duplicating apparatus, and heated and pressed (embossed) with an opposing roller, A relief composed of a fine uneven pattern was formed. Immediately after the shaping, the hologram layer 15 was formed by irradiating and curing with ultraviolet rays using a high-pressure mercury lamp.
On the relief surface of the hologram layer 15, aluminum having a thickness of 50 nm was formed by a vacuum deposition method to form a metal reflection layer 17.
The adhesive layer composition TM-A1HS (manufactured by Dainichi Seika Co., Ltd., trade name) is applied to the surface of the metal reflective layer 17 with a gravure coater so that the coating amount after drying is 1 μm, and dried at 100 ° C. Then, the adhesive layer 19 is formed, and the substrate 11 / peeling layer 13 / hard coat layer 14 / primer layer 23 / printing layer 21 / primer layer 23 / hologram layer 15 / metal reflective layer 17 / adhesive layer 19 layer structure The transfer foil 10 for in-mold of Example 1 which consists of this was obtained.

Example 2 In-mold transfer foil 10 of Example 2 in the same manner as Example 1 except that the following composition was used as the ionizing radiation curable resin composition of the hard coat layer 14 and the hologram layer 15. Got.
・ <Ionizing radiation curable resin composition of hard coat layer>
Iupimer UV / V3031 (Mitsubishi Chemical Corporation, trade name) 30 parts Purple light 6630B (Nippon Gosei Chemical Co., trade name) 5 parts Polyethylene wax (average particle size 5 μm) 4 parts Photopolymerization initiator (Ciba, trade name) Irgacure 907) 0.9 part Solvent (ethyl acetate: methyl isobutyl ketone = 1: 1) 70 parts <Ionizing radiation curable resin composition of hologram layer>
Iupimer UV / V3031 (Mitsubishi Chemical Co., Ltd., trade name) 30 parts Purple light 6630B (Nippon Synthetic Chemical Co., trade name) 5 parts Reactive silicone (Shin-Etsu Chemical Co., trade name X-22-2445) 0.2 parts Photopolymerization initiator (manufactured by Ciba, trade name Irgacure 907) 0.9 part Solvent (ethyl acetate: methyl isobutyl ketone = 1: 1) 70 parts

(Evaluation test) Evaluation was made on a plate at the time of hologram duplication, and evaluation was performed by sticking, burr at the time of in-mold injection molding, whitening of the hologram of a three-dimensional molded product, and delamination.
A plate used for hologram duplication is a plate used when forming a fine unevenness with a press stamper (plate) in producing the in-mold transfer foil 10 of Examples 1 and 2, and there is no problem. The product was accepted, and it was made a little, but it was also accepted if there were no practical problems.
Adhesion is the adhesion to the plate when forming fine irregularities with a press stamper (plate), and those that do not have a problem with shaping are accepted, and those that are in close contact and that interfere with production are rejected. .
The burr during in-mold injection molding and the whitening of the hologram of the three-dimensional molded product were first injection-molded as follows. The in-mold transfer foil 10 of Examples 1 and 2 was inserted (inserted) into the automatic foil feeder of the injection molding apparatus so that the adhesive layer surface was on the molded resin side, and Sumipex STH-55 (manufactured by Sumitomo Chemical Co., Ltd., acrylic) Resin product name) was injection molded under normal conditions of a melting temperature of 250 ° C and a mold temperature of 80 ° C. After cooling, the mold was released, and the base material 11 was peeled off together with the release layer 13 and taken out to obtain a three-dimensional molded product with a hologram using an in-mold transfer foil. The injection molding was continuously performed with a molding cycle of 12 seconds. The obtained three-dimensional molded product was assumed to have a three-dimensional shape (a member of a CD player having a diameter of 150 mm with a 5 mm border on the periphery and a central portion raised to a spherical shape).
The burrs at the time of in-mold injection molding are such that when the mold is released after injection molding and the substrate 11 / release layer 13 is peeled off, the burrs of the hard coat layer 14 and the hologram layer 15 are visually observed. Those with almost no burr were accepted, and those with some burrs but no practical problems were also accepted.
For the whitening of the hologram of the three-dimensional molded product, the mold is released after injection molding, the hologram layer 15 transferred to the three-dimensional molded product is visually observed, and the one without whitening is accepted, and there is some whitening. However, those with no practical problems were also accepted.
In the delamination, the mold is released after injection molding, the hard coat layer 14 and the hologram layer 15 transferred to the three-dimensional molded product are visually observed, and no delamination is observed in all layers including this interlayer. Things were accepted.

(Evaluation) In Examples 1 and 2, all of “taken plate, sticking, burr, whitening, peeling” were acceptable. In addition, the hard coat layer 14 and the hologram layer 15 before curing in Examples 1 and 2 were both in a finger dry state and could be wound, and the subsequent steps could be roll-to-rolled. The breaking elongation of the hard coat layer 14 and the hologram layer 15 of Example 1 was 31%, and the breaking elongation of the hard coat layer 14 and the hologram layer 15 of Example 2 was 31%.
The heat resistance of the in-mold transfer foil 10 was 170 ° C. in Example 1 and 170 ° C. in Example 2. Moreover, the transfer foil 10 for in-mold of Examples 1-2 followed any spherical molded part and the spherical part and the edging part, and was transcribe | transferred to the acrylic resin surface, there was no peeling of a layer, and a hologram was normal without a crack. I was able to transfer to.

  Moreover, the pencil hardness test of the hard-coat layer 14 surface used as the outermost surface of the three-dimensional molded product 100 using the in-mold transfer foil 10 of Examples 1-2 was measured based on JIS-K-5400. However, it had a hardness of 2H or more, and the scratch strength was 200 g or more of sapphire, so that it had sufficient durability.

It is sectional drawing of the transfer foil for in-mold which shows one Example of this invention. It is sectional drawing of the solid molded product transcribe | transferred using the transfer foil for in-mold of this invention.

Explanation of symbols

10: Transfer foil for in-mold 11: Base material 13: Release layer 14: Hard coat layer 15: Hologram layer 17: Metal reflective layer 19: Adhesive layer 21: Print layer 23: Primer layer 100: Three-dimensional molded product 101: Injection resin

Claims (2)

In the transfer foil for in-mold, in which a release layer, a hard coat layer, a print layer, a hologram layer, a metal reflection layer, and an adhesive layer are provided on one surface of the substrate and the substrate,
The release layer is a melamine resin, the hologram layer is a layer formed by curing a composition containing the following (1), (2) and (3) with ionizing radiation, and the hard coat layer is It is a layer formed by curing a composition containing (1) of the same resin as the hologram layer and (2) of the same resin with ionizing radiation, and the hard coat layer and the hologram layer are (a) before ionizing radiation curing (B) The breaking elongation at 23 ° C. after curing with ionizing radiation is 5% or more. (C) Substrate, release layer, hard coat layer, printed layer, hologram layer, metal An in-mold transfer foil having heat resistance that does not whiten even if left in a 150 ° C. atmosphere in an in-mold transfer foil state provided with a reflective layer and an adhesive layer.
(1) is (i) an isocyanate having three or more isocyanate groups in the molecule, and (b) a polyfunctional (meth) acrylate having at least one hydroxyl group and at least two (meth) acryloyloxy groups in the molecule. Or (c) a urethane (meth) acrylate oligomer that is a reaction product of a polyhydric alcohol having at least two hydroxyl groups in the molecule,
(2) is one or more selected from urethane (meth) acrylate oligomers having ether units or ester units,
(3) is silicone oil or reactive silicone. Using the in-mold transfer foil according to claim 1, a hard coat layer, a printed layer, a hologram layer, a metal reflective layer, and an adhesive layer are transferred to a three-dimensional molded product molded by an in-mold injection molding method. Three-dimensional molded product characterized by that.