JP2015085589A - In-mold transfer foil and molded article using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an in-mold transfer foil capable of forming a molded article having high surface strength while forming a three-dimensional irregularity on a decorative printing layer, and a molded article using the same.SOLUTION: In an in-mold transfer foil 100, on one surface of a base film 1, a release layer 2, a hard coat layer 3 including an after-cure type ultraviolet curable resin, an irregularity forming layer 6 including an ultraviolet curable resin, an ink reflective layer 7, and an adhesion layer 8 are laminated in this order. An ultraviolet blocking layer 4 is interposed between the hard coat layer 3 and the irregularity forming layer 6.

Description

  The present invention relates to an in-mold transfer foil, and more particularly to an in-mold transfer foil suitable for decorating industrial products.

Molded products using the in-mold transfer foil are used in equipment bodies such as daily necessities and daily necessities, containers for food and various articles, housings for electronic equipment and office supplies, and the like.
The in-mold transfer foil is a transfer foil for plastic decorative molding in which, for example, a release layer, a print layer, and an adhesive layer are formed on a base film serving as a base material. Further, in-mold molding is performed by supplying an in-mold transfer foil between a pair of injection molds, filling a cavity formed by the injection mold with heat-pressed molding resin, and then separating the base film and the release mold. This is a molding method in which the mold layer is peeled off and the printed layer is transferred to a molding resin for decoration.

  As an in-mold transfer foil for obtaining molded products with high surface strength, an ultraviolet curable resin that is solid even when not irradiated with ultraviolet rays is formed on the release layer as a hard coat layer, on which a decorative printing layer In some cases, an adhesive layer or the like is formed. This type of in-mold transfer foil is called after-cure type in-mold transfer foil. After the hard coat layer and decorative print layer are transferred to the surface of the molded product by injection molding, the hard coat layer is irradiated with ultraviolet rays. Curing of both the moldability (crack resistance) and hardness of the foil. In the case of this after-curing type in-mold transfer foil, if the hard coat layer is cured by irradiating with ultraviolet rays before molding, the moldability is impaired and the appearance becomes poor.

Since the conventional in-mold transfer foil has a structure in which characters, designs, and the like are simply printed on a base film in a flat manner, there is a problem that a three-dimensional effect is poor in decorative expression.
As a method for expressing the three-dimensional effect, there is a method for providing a three-dimensional effect by forming irregularities in the decorative printing layer as a method for expressing the three-dimensional effect (for example, see Patent Document 1).

Japanese Patent No. 3813799

However, in order to form a three-dimensional representation, such as the method described in Patent Document 1, screen printing is often performed with an ultraviolet curable screen ink, and ultraviolet irradiation is performed in this printing process. There is a problem that foil cannot be used.
In addition, industrial products are expected to be used over a long period of time or in harsh environments, so the in-mold transfer foil used for decorating industrial products has a higher surface strength than the molded product after transfer. A transfer foil is required.

Therefore, it is desirable to use an in-mold transfer foil in which a hard coat layer is formed on a release layer and a printed layer, an adhesive layer, and the like are formed on the hard coat layer, for decorating industrial products.
However, since most hard coat layers used in in-mold transfer foils are made of UV-curing resin, providing an indentation-forming layer using UV-curing resin irradiates the in-mold transfer foil with UV rays before molding. In other words, the hard coat layer made of an ultraviolet curable resin is cured before molding. For this reason, the moldability of the in-mold transfer foil is impaired, and a problem that defective products are likely to occur occurs.

  The present invention is intended to solve such problems, and is capable of providing a molded article having high surface strength while forming unevenness with a three-dimensional effect on the decorative printing layer. An object is to provide a mold transfer foil and a molded product using the same.

In order to achieve the above object, one embodiment of the present invention is to form a release layer, a hard coat layer made of an after-curing type ultraviolet curable resin, and unevenness made of an ultraviolet curable resin on one surface of a base film. An in-mold transfer foil in which a layer, a reflective layer, and an adhesive layer are laminated in this order,
An in-mold transfer foil, wherein an ultraviolet blocking layer is interposed between the hard coat layer and the unevenness forming layer.

Another embodiment of the present invention is the in-mold transfer foil, wherein the ultraviolet blocking layer is a cured product of an acrylic polymer having a hydroxyl group and an ultraviolet absorbing functional group and an isocyanate compound.
Another embodiment of the present invention is the in-mold transfer foil, wherein the unevenness forming layer is an ultraviolet curable resin containing at least a urethane acrylate oligomer, an isocyanate compound, and an extender pigment.

Another embodiment of the present invention is the in-mold transfer foil, wherein the reflective layer includes at least one of an aluminum filler and a pearl pigment.
One embodiment of the present invention is the in-mold transfer foil, wherein the reflective layer is a tin vapor deposition film and has a total light transmittance of 5% or more.
Another embodiment of the present invention is a molded article manufactured by an in-mold injection molding method using the in-mold transfer foil.

  According to one embodiment of the present invention, the hard coat layer does not proceed with cross-linking and curing due to ultraviolet rays at the time of forming the unevenness, and excellent moldability (such as crack resistance) can be maintained. Thus, it is possible to provide a molded product having excellent three-dimensional effect.

It is a figure which shows schematic structure of the in-mold transfer foil of 1st embodiment of this invention. It is a figure which shows schematic structure of the molded article using the in-mold transfer foil of 1st embodiment of this invention. It is a figure which shows schematic structure of the in-mold transfer foil of 2nd embodiment of this invention. It is a figure which shows schematic structure of the molded article using the in-mold transfer foil of 2nd embodiment of this invention.

Embodiments of the present invention will be described below with reference to the drawings.
(First embodiment)
Hereinafter, a first embodiment of the present invention (hereinafter referred to as the present embodiment) will be described with reference to the drawings.
(In-mold injection molding method)
The in-mold injection molding method includes a step of preparing an in-mold transfer foil, a step of inserting the in-mold transfer foil into an injection mold, and an injection molding of the resin to the injection mold. Thus, there are four steps: a step of transferring the in-mold transfer foil to the surface of the resin, and a step of opening the injection mold after cooling the resin, peeling the base film and the release layer and taking out the molded product. It is an injection molding method. In the present invention, ultraviolet rays and UV have the same meaning.

(overall structure)
FIG. 1 is a diagram showing a schematic configuration of the in-mold transfer foil of the present embodiment, and is a schematic cross-sectional view of the in-mold transfer foil as viewed from the side. Moreover, FIG. 2 is a figure which shows schematic structure of the molded article using the in-mold transfer foil of this embodiment, and is the cross-sectional schematic diagram which looked at the molded article from the side.
As shown in FIG. 1, the in-mold transfer foil 100 includes a base film 1, a release layer 2, a hard coat layer 3, an ultraviolet blocking layer 4, a decorative printing layer 5, and an unevenness forming layer 6. Ink reflecting layer 7 and adhesive layer 8 are provided.

In addition, in this embodiment, as shown in FIG. 1, the case where the decorative printing layer 5 by an anchor layer or color ink is inserted between the ultraviolet blocking layer 4 and the unevenness forming layer 6 is shown as an example. However, the configuration of the in-mold transfer foil 100 is not limited to this, for example, between the hard coat layer 3 and the ultraviolet blocking layer 4, or between the ink reflecting layer 7 and the adhesive layer 8, The decorative print layer 5 may be inserted.
As shown in FIG. 2, the molded product 200 using the in-mold transfer foil 100 includes an injection molding resin 11, a hard coat layer 3, an ultraviolet blocking layer 4, and an unevenness formation layer 6 provided in the in-mold transfer foil 100. Ink reflecting layer 7 and adhesive layer 8 are provided.

(Specific configuration of in-mold transfer foil 100 and molded product 200)
Hereinafter, specific configurations of the in-mold transfer foil 100 and the molded product 200 will be described with reference to FIGS. 1 and 2.
・ Base film 1
As a material for forming the base film 1, for example, a polyester resin, a polyamide resin, a polyolefin resin, a vinyl resin, an acrylic resin, a cellulose resin, a polycarbonate resin, or the like can be used. Preferably, a polyethylene terephthalate resin film is optimal in terms of heat resistance and mechanical strength.

・ Release layer 2
The release layer 2 is formed on one surface of the base film 1 (the lower surface in FIG. 1).
The material of the release layer 2 is not particularly limited as long as it has a necessary release property, but the in-mold transfer foil 100 of the present embodiment uses an olefin-modified acrylic melamine resin or acrylic urethane resin. Is preferred. In addition, as a method for forming the release layer 2, a known printing method or coating method can be used.

・ Hard coat layer 3
The hard coat layer 3 is a layer that becomes an outermost surface layer of the molded product 200 when the base film 1 is peeled off after transfer, and is a layer containing an after-curing type ultraviolet curable resin.
Moreover, as a material of the hard coat layer 3, for example, a material that is in a tack-free state and is made of a resin that can be cross-linked by irradiating with ultraviolet rays after being transferred to a transfer object. Here, as a reason for crosslinking after transfer, the in-mold transfer foil 100 of the present embodiment is often used in injection molding or a heat transfer method. This is because the appearance is poor.

In addition, there are mainly three methods (first to third methods) described below as a method for realizing tack-free property (no stickiness by simply evaporating the solvent) before transfer. .
The first method is a method using a polymer acrylate or methacrylate.
The second method is a method in which a liquid or semi-liquid ultraviolet curable resin is slightly cured with a crosslinking system such as isocyanate / polyol resin or epoxy resin / amines to make it tack-free.

The third method is a method in which a semi-cured state is obtained by slightly irradiating ultraviolet rays or an electron beam.
In the case of the first method, an acryloyl group or a methacryloyl group having a weight average molecular weight of 40,000 or more and a glass transition temperature of 60 ° C. or more is used for tack-free and preventing the resin from flowing during injection molding. It is preferable to use an acrylic resin (acrylic acrylate) containing This is because when the weight average molecular weight is less than 40,000, tack-free property is not sufficient, there is a problem in top coatability, and washout is likely to occur during molding. Moreover, when the weight average molecular weight exceeds 100,000, the radical reactivity is lowered, and the hardness at the time of crosslinking may not be increased. Such acrylic acrylate generally has advantages such as tack-free properties and less curing shrinkage compared to oligomers and monomers used in UV curable resins, but it is a polymer resin. In order to compensate for the inferior surface hardness due to the tendency of inferior curability, it is necessary to add nano silica particles. Moreover, if the addition amount is less than 10 weight% with respect to acrylic acrylate resin, the effect on hardness is not seen. On the other hand, if it exceeds 40% by weight, it becomes too brittle and the wear resistance is poor. Therefore, the optimal addition amount is in the range of 10 wt% to 40 wt% with respect to the acrylic acrylate resin. The weight average molecular weight is a value calculated by GPC measurement by styrene conversion. Further, the optimum range is that the weight average molecular weight is in the range of 60,000 or more and 80,000 or less, and the nanosilica particle amount is in the range of 15% by weight or more and less than 35% by weight.
As a method for forming the hard coat layer 3, a known printing method or coating method can be used.

・ UV blocking layer 4
As a material of the ultraviolet blocking layer 4, for example, a material having adhesiveness with the hard coat layer 3, which absorbs or reflects light within a wavelength range of 200 nm to 380 nm to transmit ultraviolet light. It is possible to use a material having a performance capable of blocking or reducing the above.

  Here, examples of materials having ultraviolet blocking ability include metal oxide fillers such as zinc oxide and cesium oxide, benzotriazole ultraviolet absorbers, benzophenone ultraviolet absorbers, cyanoacrylate ultraviolet absorbers, and salicylate ultraviolet absorbers. Agents, organic ultraviolet absorbers such as oxanilide ultraviolet absorbers, or resins covalently bonded to these ultraviolet absorbers.

However, UV absorbers generally have many low molecular weight materials, and are easily transferred to the hard coat layer 3 and the unevenness forming layer 6, and are hard to cure during the formation of the hardcoat layer 3 and unevenness forming layer 6. Insufficient adhesion between the layers, blocking, and heat at the time of injection molding may cause uneven shape deformation.
Therefore, the resin used as the material for the ultraviolet blocking layer 4 is preferably a polymer having an ultraviolet absorbing functional group in the molecule (ultraviolet absorbing polymer). Furthermore, from the viewpoint of adhesion, the material of the ultraviolet blocking layer 4 is preferably a cured product of an acrylic polymer having a hydroxyl group and an ultraviolet absorbing functional group and an isocyanate compound.

Thus, by making the material of the ultraviolet blocking layer 4 a two-component curable acrylic resin, it can withstand heat during injection molding, has a high affinity with the acrylic ultraviolet curable resin, and has good adhesion. Become.
The isocyanate compound refers to toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), xylylene diisocyanate (XDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), and prepolymers thereof.

As a standard of ultraviolet blocking ability, it is desirable that the transmittance of i-line (wavelength 365 nm) is less than 10%. This is because when forming irregularities with an ultraviolet curable resin, it is necessary to irradiate the irregularity-forming layer 6 with ultraviolet rays having a light amount within a range of 500 mJ / cm ² or more and 1000 mJ / cm ² or less. If the hard coat layer 3 is irradiated with ultraviolet rays of about 100 mJ / cm ² or more before injection molding, the hard coat layer 3 cannot follow the stretching during the injection molding due to the progress of the cross-linking reaction, and the hard coat layer 3 is cracked. This is because it will occur.

・ Decorative printing layer 5
As a material for the decorative printing layer 5, for example, a colored ink containing a pigment or dye of an appropriate color as a colorant is used.
As a method for forming the decorative printing layer 5, for example, a normal printing method such as an offset printing method, a gravure printing method, a screen printing method, an ink jet method, or the like can be used. It is preferable to print by a gravure printing method that can perform multicolor printing and gradation expression and is suitable for mass production.

・ Unevenness forming layer 6
The concavo-convex forming layer 6 is cured by UV printing from the side of the releasable concavo-convex film by sandwiching the releasable concavo-convex film and the base film with a liquid ultraviolet curable resin, using a screen printing method or UV inkjet method using a UV thick ink. Then, it can be formed by peeling the releasable uneven film.

As long as the concave / convex design of the concave / convex forming layer 6 can express a three-dimensional feeling such as a geometric pattern or a hairline shape, anything may be used. In addition, in the case of uneven | corrugated formation by a releasable uneven | corrugated film, fine expressions, such as a hologram and a photonic crystal, are also possible.
Concavity and convexity formation with these ultraviolet-curing resins has better reproducibility of the concave and convex shape compared to the formation of concavity and convexity with thermosetting resin, and the manufacturing time can be shortened.

As the material of the unevenness forming layer 6, for example, an ultraviolet curable resin composed of a monomer having an acryloyl group or a methacryloyl group, an oligomer such as polyester acrylate, epoxy acrylate, or urethane acrylate, or a polymerization initiator that generates radicals by ultraviolet rays is used. Is possible.
Moreover, as the material of the unevenness forming layer 6, among the materials described above, an ultraviolet curable resin containing at least a urethane acrylate oligomer, an isocyanate compound, and an extender pigment is optimal. In general, the oligomer used for the UV curable resin includes polyester acrylate, epoxy acrylate, and urethane acrylate. In the unevenness forming layer 6, urethane acrylate is used from the viewpoint of adhesion between layers and stretchability at the time of molding. good.

  Furthermore, it is preferable to add an isocyanate compound as a material for the unevenness forming layer 6 in order to improve the adhesion between the layers. The addition amount of the isocyanate compound is preferably in the range of 1% by weight to 10% by weight with respect to the ultraviolet curable oligomer. In addition, by adding extender pigment to the unevenness forming layer 6, the scattering component is added to the uneven shape, and the three-dimensional effect is increased, the shape stability effect when forming unevenness due to the thixotropy of the extender pigment, and the adhesiveness due to the increased surface area There is an improvement effect. Here, the extender pigment is a colorless and transparent pigment (or white pigment), and refers to fine particles such as silica, alumina, calcium carbonate, barium sulfate and the like.

・ Ink reflection layer 7
The ink reflecting layer 7 is a layer that reflects or scatters light, and it is sufficient that the uneven structure of the uneven forming layer 6 can be visualized.
When the material of the ink reflecting layer 7 is a material such as medium ink or black ink, the uneven structure is buried and is hardly visible. On the other hand, when the material of the ink reflection layer 7 is a high-brightness material such as an aluminum filler or a pearl pigment, the uneven structure is conspicuous because the orientation of the filler or pigment is locally disturbed by the uneven structure.

  In addition, when the material of the ink reflection layer 7 is a high-brightness material such as an aluminum filler or a pearl pigment, it is not a continuous reflection film such as an aluminum vapor deposition film. Here, the aluminum filler is a flake-like or irregularly shaped particle made of aluminum, and in addition to the untreated surface product, there is also a filler whose surface is coated to improve durability and designability. A pearl pigment is a pigment in which a mica is coated with a metal oxide film such as titanium oxide or iron oxide, and a boundary between a metal oxide film layer having a high refractive index and mica having a low refractive index and its surrounding medium. It is a pigment that reflects and interferes with light.

・ Adhesive layer 8
The adhesive layer 8 adheres each of the above layers to the surface of the molded product 200.
As a material for the adhesive layer 8, for example, a heat-sensitive or pressure-sensitive resin suitable for the injection molding resin 11 is appropriately used.
As a method for forming the adhesive layer 8, for example, a printing method such as a gravure printing method or a screen printing method can be used. In particular, from the viewpoint of film thickness and productivity, it is desirable to print by a gravure printing method. In addition, when the ink reflection layer 7 has sufficient adhesiveness with respect to the molded article 200 and also has an effect as an adhesive layer, the adhesive layer 8 may not be provided.

  As described above, the layers are laminated as described above to form the in-mold transfer foil 100 of the present embodiment.

(Method for producing molded product 200)
Hereinafter, with reference to FIG.1 and FIG.2, the manufacturing method of the molded article 200 is demonstrated.
The molded product 200 is manufactured by injection molding using the in-mold transfer foil 100.
Injection molding of the in-mold transfer foil 100 is performed by inserting the in-mold transfer foil 100 into an injection mold and injection molding from the decorative printing layer 5 side of the in-mold transfer foil 100 into the cavity of the injection mold. The in-mold transfer foil 100 is transferred onto the surface of the injection molding resin 11 by injection molding the resin 11. Furthermore, after the injection molding resin 11 is cooled, the injection mold is released, the base film 1 and the release layer 2 of the in-mold transfer foil 100 are peeled off, and the molded product 200 is taken out in a known order. It is possible.
This method makes it possible to manufacture a molded article 200 (see FIG. 2) having a three-dimensional effect.

(Second embodiment)
Next, a second embodiment of the present invention (hereinafter referred to as the present embodiment) will be described using FIGS. 3 and 4 with reference to FIGS. 1 and 2. In addition, description may be abbreviate | omitted about the structure similar to 1st embodiment mentioned above.

(overall structure)
FIG. 3 is a diagram showing a schematic configuration of the in-mold transfer foil of the present embodiment, and is a schematic cross-sectional view of the in-mold transfer foil as viewed from the side. Moreover, FIG. 4 is a figure which shows schematic structure of the molded article using the in-mold transfer foil of this embodiment, and is the cross-sectional schematic diagram which looked at the molded article from the side.
As shown in FIG. 3, the in-mold transfer foil 100 includes a base film 1, a release layer 2, a hard coat layer 3, an ultraviolet blocking layer 4, a decorative printing layer 5, and an unevenness forming layer 6. , An adhesive layer 8, a vapor deposition reflective layer 9, and a primer layer 10.

In the present embodiment, as an example, as shown in FIG. 3, a case in which a decorative print layer 5 with an anchor layer or color ink is interposed between the ultraviolet blocking layer 4 and the unevenness forming layer 6 is shown. However, the configuration of the in-mold transfer foil 100 is not limited to this. For example, the decorative print layer 5 may be interposed between the hard coat layer 3 and the ultraviolet blocking layer 4.
As shown in FIG. 4, the molded product 200 using the in-mold transfer foil 100 includes an injection molding resin 11, a hard coat layer 3, an ultraviolet blocking layer 4, and an unevenness formation layer 6 provided in the in-mold transfer foil 100. , An adhesive layer 8, a vapor deposition reflective layer 9, and a primer layer 10.

(Specific configuration of in-mold transfer foil 100 and molded product 200)
Hereinafter, specific configurations of the in-mold transfer foil 100 and the molded product 200 will be described with reference to FIGS. 1 to 4.
・ Base film 1
As a material for the base film 1, it is possible to use polyester resin, polyamide resin, polyolefin resin, vinyl resin, acrylic resin, cellulose resin, polycarbonate resin, or the like. Preferably, a polyethylene terephthalate resin film is optimal in terms of heat resistance and mechanical strength.

・ Release layer 2
The material of the release layer 2 is not particularly limited as long as it has a necessary release property, but the in-mold transfer foil 100 of the present embodiment uses an olefin-modified acrylic melamine resin or acrylic urethane resin. Is preferred. In addition, as a method for forming the release layer 2, a known printing method or coating method can be used.

・ Hard coat layer 3
The hard coat layer 3 is a layer that becomes the outermost surface layer of the molded product 200 when the base film 1 is peeled off after transfer.
The material of the hard coat layer 3 is preferably in a tack-free state, and is preferably made of a resin that can be cross-linked by irradiating ultraviolet rays after being transferred to the transfer object. Here, the reason for crosslinking after transfer is that this transfer foil is often used in injection molding and heat transfer methods, but if crosslinked in advance, cracks tend to occur during transfer stretching, resulting in poor appearance. is there. In addition, there are mainly the following three methods (first to third methods) for realizing tack-free property before transfer.

The first method is a method using a polymer acrylate or methacrylate.
The second method is a method in which a liquid or semi-liquid ultraviolet curable resin is slightly cured with a crosslinking system such as an isocyanate / polyol resin or an epoxy resin / amine to make it tack-free.
The third method is a method of slightly irradiating ultraviolet rays or an electron beam to make it a semi-cured state.

In the case of the first method, an acryloyl group or a methacryloyl group having a weight average molecular weight of 40,000 or more and a glass transition temperature of 60 ° C. or more is used for tack-free and preventing the resin from flowing during injection molding. The acrylic resin (acrylic acrylate) to contain is preferable. This is because when the weight average molecular weight is less than 40,000, tack-free property is not sufficient, there is a problem in top coatability, and washout is likely to occur during molding. Moreover, when the weight average molecular weight exceeds 100,000, the radical reactivity is lowered, and the hardness at the time of crosslinking may not be increased. Such acrylic acrylate is generally a polymer resin, while it has advantages such as tack-free properties and less curing shrinkage compared to oligomers and monomers used in UV curable resins. In order to compensate for the poor surface hardness and the surface hardness, it is necessary to add nano silica particles. If the amount added is less than 10% by weight with respect to the acrylic acrylate resin, no effect on hardness is observed, and if it exceeds 40% by weight, it becomes too brittle and has poor wear resistance. It is in the range of 10 wt% to 40 wt% with respect to the resin. The weight average molecular weight is a value calculated by GPC measurement by styrene conversion. Further, the optimum range is that the weight average molecular weight is in the range of 60,000 or more and 80,000 or less, and the nanosilica particle amount is in the range of 15% by weight or more and less than 35% by weight.
As a method for forming the hard coat layer 3, a known printing method or coating method can be used.

・ UV blocking layer 4
The material of the ultraviolet blocking layer 4 is, for example, a material having adhesiveness with the hard coat layer 3 and absorbs or reflects light within the range of 200 nm to 380 nm as the wavelength of light, thereby transmitting ultraviolet light. It is possible to use a material having the performance of blocking or reducing the above.

  Examples of materials having ultraviolet blocking ability include metal oxide fillers such as zinc oxide and cesium oxide, benzotriazole-based UV absorbers, benzophenone-based UV absorbers, cyanoacrylate-based UV absorbers, salicylate-based UV absorbers, and oxanilide-based UV rays. It is possible to use an organic ultraviolet absorber such as an absorber or a resin obtained by covalently bonding these ultraviolet absorbers.

However, UV absorbers generally have many low molecular weight materials, and are easily transferred to the hard coat layer 3 and the unevenness forming layer 6, and are hard to cure during the formation of the hardcoat layer 3 and unevenness forming layer 6. Insufficient adhesion between layers, blocking, and uneven shape deformation may occur due to heat during injection molding.
Therefore, as the resin used as the material of the ultraviolet blocking layer 4, it is preferable to use a polymer (ultraviolet absorbing polymer) having an ultraviolet absorbing functional group in the molecule. Further, from the viewpoint of adhesion, the material of the ultraviolet blocking layer 4 is preferably a cured product of an acrylic polymer having a hydroxyl group and an ultraviolet absorbing functional group and an isocyanate compound.

Thus, by making the material of the ultraviolet blocking layer 4 into a two-component curable acrylic resin, it can withstand the heat during injection molding, has high affinity with the acrylic ultraviolet curable resin, and has good adhesion. Become.
The isocyanate compound refers to toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), xylylene diisocyanate (XDI), hexamethylene diisocyanate (HDI), isophorone diisocyanate (IPDI), and prepolymers thereof.

As a standard of ultraviolet blocking ability, it is desirable that the transmittance of i-line (wavelength 365 nm) is less than 10%. This is because when forming irregularities with an ultraviolet curable resin, it is necessary to irradiate the irregularity-forming layer 6 with ultraviolet rays having a light amount within a range of 500 mJ / cm ² or more and 1000 mJ / cm ² or less. If the hard coat layer 3 is irradiated with ultraviolet rays of about 100 mJ / cm ² or more before injection molding, the hard coat layer 3 cannot follow the stretching during the injection molding due to the progress of the cross-linking reaction, and the hard coat layer 3 is cracked. This is because it will occur.

・ Decorative printing layer 5
As a material for the decorative printing layer 5, for example, a colored ink containing a pigment or dye of an appropriate color as a colorant is used.
As a method for forming the decorative printing layer 5, for example, a normal printing method such as an offset printing method, a gravure printing method, a screen printing method, an ink jet method, or the like can be used. It is preferable to print by a gravure printing method that can perform multicolor printing and gradation expression and is suitable for mass production.

・ Unevenness forming layer 6
The concavo-convex forming layer 6 is cured by UV printing from the side of the releasable concave / convex film, with a screen printing method using UV thick ink, a UV inkjet method, or a release concavo-convex film and a base film sandwiched between liquid UV curable resins. Then, it is possible to form irregularities by peeling off the releasable uneven film.

The unevenness design of the unevenness forming layer 6 may be anything as long as it can express a three-dimensional feeling such as a geometric pattern or a hairline shape. In addition, when forming an unevenness with a releasable uneven film, a fine expression such as a hologram or a photonic crystal is possible.
The unevenness formation by these ultraviolet curable resins has better reproducibility of the uneven shape than the formation of unevenness by the thermosetting resin, and the manufacturing time can be shortened.

As the material for the concavo-convex-forming layer 6, it is possible to use a monomer having an acryloyl group or a methacryloyl group, an oligomer such as polyester acrylate, epoxy acrylate, urethane acrylate, or an ultraviolet curable resin comprising a polymerization initiator that generates radicals by ultraviolet rays It is.
Moreover, as the material of the unevenness forming layer 6, among the materials described above, an ultraviolet curable resin containing at least a urethane acrylate oligomer, an isocyanate compound, and an extender pigment is optimal. In general, the oligomer used for the UV curable resin includes polyester acrylate, epoxy acrylate, and urethane acrylate. In the unevenness forming layer 6, urethane acrylate is used from the viewpoint of adhesion between layers and stretchability at the time of molding. good.

  Furthermore, it is preferable to add an isocyanate compound as a material for the unevenness forming layer 6 in order to improve the adhesion between the layers. The addition amount of the isocyanate compound is preferably in the range of 1% by weight to 10% by weight with respect to the ultraviolet curable oligomer. In addition, by adding extender pigment to the unevenness forming layer 6, the scattering component is added to the uneven shape, and the three-dimensional effect is increased, the shape stability effect when forming unevenness due to the thixotropy of the extender pigment, and the adhesiveness due to the increased surface area There is an improvement effect. Here, the extender pigment is a colorless and transparent pigment (or white pigment), and refers to fine particles such as silica, alumina, calcium carbonate, barium sulfate and the like.

・ Adhesive layer 8
The adhesive layer 8 adheres each of the above layers to the surface of the molded product 200.
As a material for the adhesive layer 8, for example, a heat-sensitive or pressure-sensitive resin suitable for the injection molding resin 11 is appropriately used.
As a method for forming the adhesive layer 8, a printing method such as a gravure printing method or a screen printing method can be used. In particular, it is desirable to print by a gravure printing method from the viewpoint of film thickness and productivity. In addition, when the primer layer 10 has sufficient adhesiveness with respect to a molded article and also has the effect as an adhesive layer, it is not necessary to provide the adhesive layer 8 separately.

・ Vapor deposition reflective layer 9
As the vapor deposition reflective layer 9, it is preferable to use a tin vapor deposition film that forms a discontinuous film (sea-island structure).
Here, when the total light transmittance of the tin vapor deposition film is less than 5%, it is not preferable because it is not a discontinuous film, conductivity is increased, and radio wave permeability is decreased. Further, when the total light transmittance of the tin vapor deposition film is less than 5%, the tin vapor deposition film cannot follow the elongation of the resin during molding, and cracks are easily generated and recognized.
On the other hand, when the total light transmittance of the tin vapor deposition film exceeds 25%, the light reflectivity is remarkably lowered, resulting in a dim appearance and an unfavorable design.
Therefore, the vapor deposition reflective layer 9 is particularly preferably formed of a tin vapor deposition film having a total light transmittance of 5% or more and 25% or less.

・ Primer layer 10
The primer layer 10 is preferably a vinyl chloride-based resin or a melamine-based resin because it is preferable to have a good adhesion with the tin vapor deposition film and prevent oxidation of the tin film. Moreover, since the vapor deposition reflective layer 9 is half vapor deposition (with transparency), if white ink is used for the primer layer 10, a bright reflective color close to that of the aluminum vapor deposition film is obtained, and black ink is used for the primer layer 10. For example, it becomes a calm reflection color close to a chromium vapor deposition film.
As described above, the layers are laminated as described above to form the in-mold transfer foil 100 of the present embodiment.

(Method for producing molded product 200)
Hereinafter, with reference to FIG.3 and FIG.4, the manufacturing method of the molded article 200 is demonstrated.
The molded product 200 is manufactured by injection molding using the in-mold transfer foil 100.
Injection molding of the in-mold transfer foil 100 is performed by inserting the in-mold transfer foil 100 into an injection mold and injection molding from the decorative printing layer 5 side of the in-mold transfer foil 100 into the cavity of the injection mold. The in-mold transfer foil 100 is transferred onto the surface of the injection molding resin 11 by injection molding the resin 11. Furthermore, after the injection molding resin 11 is cooled, the injection mold is released, the base film 1 and the release layer 2 of the in-mold transfer foil 100 are peeled off, and the molded product 200 is taken out in a known order. It is possible.
By this method, it becomes possible to manufacture a molded article 200 (see FIG. 4) having a three-dimensional effect.

Hereinafter, examples of the present invention will be described with reference to FIGS. 1 to 4 and comparison results based on comparative examples. In addition, although the Example and comparative example of this invention are shown below, this invention is not limited to this.
Example 1
Using a polyethylene terephthalate resin film (50T60 manufactured by Toray) as the base film 1, a release layer 2 using a melamine resin system as a material and a hard material using an ultraviolet curable acrylic resin system as a material on the base film 1 Coat layer 3 was formed. Furthermore, the ultraviolet blocking layer 4 was formed by using a two-component curable ultraviolet absorbing polymer (Vanaresin UVA-55MHB manufactured by Shin-Nakamura Chemical Co., Ltd.) as the resin and Coronate L manufactured by Nippon Polyurethane as the curing agent.

Subsequently, as the decorative printing layer 5, a pattern is formed by a screen printing method using urethane-based color ink, and then the surface is printed by a screen printing method using a UV thick ink having the following formulation to form irregularities. Immediately after that, the unevenness was crosslinked and cured by ultraviolet irradiation (high pressure mercury lamp integrated light quantity 800 mJ / cm ² ), and the unevenness was fixed to form the unevenness forming layer 6.
Then, the reflective ink shown below was formed by the screen printing method, and the ink reflection layer 7 was formed. Thereafter, an acrylic / vinyl acetate adhesive was formed by a screen printing method to obtain an in-mold transfer foil 100 of Example 1.

-UV thick ink Teikoku ink UV thick ink (UVFIX) ... 100 parts by weight Fuji Silysia silica powder (Silo Hovic 200) ... .... 5 parts by weight Asahi Kasei Chemical isocyanate compound (24A100) ... 5 parts by weight

・ Reflective ink Toyo Ink 2-pack acrylic screen ink (SS16) ・ ・ ・ ・ ・ ・ 100 parts by weight Merck pearl pigment (Iriodin 100) ・ ・ ・ ・ ・ ・ ・ ・ ・ ・ ・5 parts by weight The above-mentioned in-mold transfer foil 100 was fixed to an injection mold, and the mold was clamped to injection-mold an injection molding resin 11 that is a PC / ABS resin. After cooling, the injection mold is opened, the base film 1 of the in-mold transfer foil 100 is peeled off from the injection molded product together with the release layer 2, and then a high pressure mercury lamp is used on the surface of the injection molded product. The molded product 200 having a high surface strength and a three-dimensional effect was obtained by irradiating ultraviolet rays with an integrated light quantity of 1000 mJ / cm ² to crosslink and cure the hard coat layer 3.

(Example 2)
A polyethylene terephthalate resin film (Toray 50T60) was used as the base film 1, a release layer 2 using an acrylic urethane resin system as a material, and an ultraviolet curable acrylic resin system as a material on the base film 1. A hard coat layer 3 was formed. Furthermore, the ultraviolet blocking layer 4 was formed by using a two-component curable ultraviolet absorbing polymer (Vanaresin UVA-55MHB manufactured by Shin-Nakamura Chemical Co., Ltd.) as the resin and Coronate L manufactured by Nippon Polyurethane as the curing agent.

Subsequently, as the decorative printing layer 5, a pattern is formed by a screen printing method using urethane-based color ink, and then the surface is printed by a screen printing method using a UV thick ink having the following formulation to form irregularities. Immediately after that, the unevenness was crosslinked and cured by ultraviolet irradiation (high pressure mercury lamp integrated light quantity 800 mJ / cm ² ), and the unevenness was fixed to form the unevenness forming layer 6.
Subsequently, by using tin as a material, the film was formed so as to have a total light transmittance of 5% by a vacuum vapor deposition method, and the vapor deposition reflective layer 9 was formed. Next, the primer layer 10 is formed by a gravure printing method using a primer ink having the following formulation, and then an acrylic / vinyl acetate adhesive is formed by a screen printing method. The in-mold transfer foil of Example 2 100 was obtained.

-UV thick ink Teikoku ink UV thick ink (UVFIX) ... 100 parts by weight Fuji Silysia silica powder (Silo Hovic 200) ... .... 5 parts by weight Asahi Kasei Chemical isocyanate compound (24A100) ... 5 parts by weight

・ Primer ink Toyo Ink salt vinegar biurethane gravure ink white (Finestar) ・ 100 parts by weight Asahi Kasei Chemical isocyanate compound (24A100) 5 parts by weight In-mold transfer foil 100 It was fixed to an injection mold, and the mold was clamped to injection mold resin 11 which is a PC / ABS resin. After cooling, the injection mold is opened, the base film 1 of the in-mold transfer foil 100 is peeled off from the injection molded product together with the release layer 2, and then a high pressure mercury lamp is used on the surface of the injection molded product. The molded product 200 having a high surface strength and a three-dimensional effect was obtained by irradiating ultraviolet rays with an integrated light quantity of 1000 mJ / cm ² to crosslink and cure the hard coat layer 3.

(Comparative example)
A polyethylene terephthalate resin film (Toray 50T60) was used as the base film 1, a release layer 2 using an acrylic urethane resin system as a material, and an ultraviolet curable acrylic resin system as a material on the base film 1. A hard coat layer 3 was formed. Furthermore, as the decorative printing layer 5, a pattern was formed by a screen printing method using urethane-based color ink.

Next, it is printed with Teikoku UV thick ink (UVFIX) by screen printing to form unevenness, and immediately after that, the unevenness is crosslinked and cured by ultraviolet irradiation (high pressure mercury lamp integrated light amount 800 mJ / cm ² ). Was fixed to form an unevenness forming layer 6.
Subsequently, using aluminum as a material, vapor deposition was performed by a vacuum vapor deposition method so that the total light transmittance was 5%, thereby forming a vapor deposition reflective layer 9. Furthermore, the primer layer 10 is formed by a gravure printing method using VM-PEARL manufactured by Dainichi Seika Kogyo, and then an acrylic / vinyl acetate adhesive is formed by a screen printing method. Obtained.

The in-mold transfer foil 100 was fixed to an injection mold, and the mold was clamped to injection-mold an injection molding resin 11 that is a PC / ABS resin. After cooling, the injection mold is opened, the base film 1 of the in-mold transfer foil 100 is peeled off from the injection molded product together with the release layer 2, and then a high pressure mercury lamp is used on the surface of the injection molded product. The molded product 200 having a high surface strength and a three-dimensional effect was obtained by irradiating ultraviolet rays with an integrated light quantity of 1000 mJ / cm ² to crosslink and cure the hard coat layer 3.

(Evaluation)
About Example 1, 2 and a comparative example, evaluation was performed about a moldability, adhesiveness, a three-dimensional effect, and radio wave permeability. The evaluation results are shown in Table 1.
In addition, the evaluation method of each item is shown below.
-Formability: No cracks when injection molding.
No crack: ○
With crack: ×

-Adhesiveness: After cross-cutting 1 mm grid, peel off with Nichiban cello tape (registered trademark).
No peeling: ○
Less than 5% peeling: △
5% or more peeled: ×
-Three-dimensional effect: visual evaluation.
There is a three-dimensional feeling: ○
No three-dimensional effect: ×

Radio wave permeability: 800 MHz radio wave attenuation rate (dB) is less than 1 dB.
Attenuation rate of less than 1 dB: ○
Attenuation rate of 1 dB or more: ×

実施例１及び実施例２では、成形性、密着性、立体感、電波透過性で優れるが、比較例では、立体感以外は規格を満たすことはできなかった。
これにより、実施例１及び実施例２のインモールド転写箔１００及び成形品２００は、比較例のインモールド転写箔１００及び成形品２００よりも、特に、成形性、密着性、電波透過性が優れていることが確認された。

In Examples 1 and 2, the moldability, adhesion, stereoscopic effect, and radio wave permeability were excellent, but in the comparative example, the standards other than the stereoscopic effect could not be satisfied.
As a result, the in-mold transfer foil 100 and the molded product 200 of Example 1 and Example 2 are particularly excellent in moldability, adhesion, and radio wave transmissibility than the in-mold transfer foil 100 and the molded product 200 of the comparative example. It was confirmed that

  The transfer film obtained by the present invention can be used for surface protection and decoration of panel members and the like used for home appliances, housing equipment, office equipment, automobile parts and the like.

DESCRIPTION OF SYMBOLS 1 Base film 2 Release layer 3 Hard coat layer 4 Ultraviolet ray blocking layer 5 Decorative printing layer 6 Concavity and convexity formation layer 7 Ink reflection layer 8 Adhesive layer 9 Deposition reflection layer 10 Primer layer 11 Injection molding resin 100 In-mold transfer foil 200 Molded product

Claims (6)

On one surface of the base film, a release layer, a hard coat layer made of an after-curing type UV curable resin, an unevenness forming layer made of an UV curable resin, a reflective layer, and an adhesive layer are laminated in this order. In-mold transfer foil,
An in-mold transfer foil, wherein an ultraviolet blocking layer is interposed between the hard coat layer and the unevenness forming layer.   The in-mold transfer foil according to claim 1, wherein the ultraviolet blocking layer is a cured product of an acrylic polymer having a hydroxyl group and an ultraviolet absorbing functional group and an isocyanate compound.   The in-mold transfer foil according to claim 1, wherein the unevenness forming layer is an ultraviolet curable resin containing at least a urethane acrylate oligomer, an isocyanate compound, and an extender pigment.   The in-mold transfer foil according to any one of claims 1 to 3, wherein the reflective layer includes at least one of an aluminum filler and a pearl pigment.   The in-mold transfer foil according to any one of claims 1 to 3, wherein the reflective layer is a tin vapor deposition film and has a total light transmittance of 5% or more.   A molded product produced by an in-mold injection molding method using the in-mold transfer foil according to any one of claims 1 to 5.

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