JPH0241242A - Transfer foil with moldability and manufacturing method thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to improvements in a releasable sheet and transfer foil that form irregularities on the surface of a molded article.

[Conventional technology]

Conventionally, in order to form irregularities on the surface of a molded product, a mold with an embossed pattern was used and a transfer foil was placed inside the mold.
Thereafter, injection molding was performed to obtain the desired molded product. However, even when only the embossed shape is changed, it is necessary to manufacture a mold according to the occasion, and the durability of the embossed shape of the mold is also poor, resulting in a very high cost. As an improvement to the above manufacturing method, a method was considered in which a flexible thermoplastic resin sheet that is easy to embossing was made in advance with embossed transfer foil and then injection molded, but the sheet did not have heat resistance. Therefore, the desired embossed shape may be deformed due to the heat applied during printing and transfer when creating the transfer foil. Furthermore, in the case of a type of transfer foil that is simultaneously transferred within the injection mold during injection molding, the deformation was even more remarkable.

[Problem to be solved by the invention]

The purpose of the present invention is to solve the problems of the conventional technology as described above, and to solve the following problems (a) to (6).
) has the purpose of

(a) To provide a releasable sheet having irregularities on the surface of an ionizing radiation-cured resin layer, which is a thermoplastic solid in an uncured state but exhibits strong hardening after irradiation with ionizing radiation.

(b) To provide a transfer foil that does not require the use of an embossed mold when a release layer, a pattern layer, and an adhesive layer are provided on the sheet and has excellent heat resistance.

(C) To provide a method for manufacturing the composite releasable sheet of (a) above.

(d) To provide a method for manufacturing a transfer foil according to (b) above.

[Means to solve the problem]

The present invention solves the above-mentioned problems, and part 1
``A releasable sheet characterized by having an ionizing radiation-hardened resin layer having irregularities on a base film.'' Part 2 is ``A releasable sheet characterized by having an ionizing radiation-curable resin layer having irregularities on a base film.'' A transfer foil characterized in that a release layer, a pattern layer and an adhesive layer are sequentially formed on the base film, and the transfer foil is characterized in that it has an ionizing radiation-cured layer on the base film which is a thermoplastic solid in an uncured state. After forming a resin layer and embossing the resin layer, ionizing radiation is irradiated to remove ionizing radiation.
Claim (1) comprising curing the curable resin layer a.
A method for producing a releasable sheet. ”, and No. 4 states, “In claim (3), after the embossing process, a release layer, a pattern layer, and an adhesive layer are sequentially formed, and then ionizing radiation is irradiated to form an ionizing radiation-curable resin. The method for manufacturing a transfer foil according to claim (2), which comprises curing the layer. Furthermore, the above-mentioned materials, materials, and implementation methods will be explained in detail.

As the base film, a heat-resistant film such as polyethylene tereftate, acrylic, polyamide, polycarbonate, triacetate, polyarylate, etc. and having a thickness of about 10 to 100 μm can be used. One of these days,
A thickness of 25 to 50 microns is effective.

As the embossing method, all normal processing methods can be used.

Any embossing plate can be used as long as it has unevenness. Furthermore, when fine embossing is used, it is possible to produce a brilliant color on the transfer molded product.

The ionizing radiation-curable resin used in the present invention is a thermoplastic material having a radically polymerizable unsaturated group, and there are two types as follows.

(1) A polymer having a glass transition temperature of 0 to 250°C and having a radically polymerizable unsaturated group. More specifically, the following methods (a) to (6) are used to polymerize or copolymerize the following compounds 1 to 2.
It is possible to use those into which radically polymerizable unsaturated groups have been introduced.

■ Monomers with hydroxyl groups: N-methylol acrylamide, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 2
-Hydroxybutyl acrylate, 2-hydroxybutyl methacrylate, 2-hydroxy-3-phenoxypropyl acrylate, etc.

■ Monomers with carboxyl groups such as nialic acid, methacrylic acid, acryloyloxyethyl monosuccinate, etc.

■ Monomers such as coglycidyl methacrylate with epoxy groups.

(2) Monomers having an aziridinyl group: 2-aziridinylethyl methacrylate, allyl 2-aziridinylpropionate, etc.

(2) Monomers having amide 7 groups such as niacrylamide, methacrylamide, diaseptone acrylamide, dimethylamine ethyl methacrylate, diethyl ethyl methacrylate, etc.

■ Monomer with sulfone group: 2-acrylamide-
2-methylpropanesulfonic acid, etc.

(1) 1 mol to 1 mol addition of monomers having an isocyanate group, 22,4-toluene diisonanate and 2-hydroxyethylene acrylate.Adducts of monomer diisocyanates and radically polymerizable monomers having active hydrogen, etc.

■Furthermore, in order to adjust the glass transition point of the above polymer or copolymer and the physical properties of the cured film,
It is also possible to copolymerize the above compound with the following monomers that are copolymerizable with this compound. Examples of such copolymerizable monomers include methyl methacrylate, methyl acrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, butyl methacrylate, inbutyl acrylate, inbutyl methacrylate, and t-butyl acrylate. , t-butyl methacrylate, inamyl acrylate, inamyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate, and the like.

Next, the material related to the present invention can be obtained by introducing radically polymerizable unsaturated groups into the polymer or copolymer obtained as described above by methods (a) to (d) described below. can.

(a) In the case of a polymer or copolymer of a monomer having a hydroxyl group, a monomer having a carboxyl group such as acrylic acid or methacrylic acid is subjected to a condensation reaction.

(b) In the case of a polymer or copolymer of monomers having a carboxyl group or a sulfone group, the aforementioned monomers having a hydroxyl group are subjected to a condensation reaction.

In the case of a polymer or copolymer of a monomer having an epoxy group, incyanate group or aziridinyl group, the above-mentioned monomer having a hydroxyl group or monomer having a carboxyl group is subjected to an addition reaction.

(dl In the case of a polymer or copolymer of a monomer having a hydroxyl group or a carboxyl group, a monomer having an epoxy group or a monomer having an aziridinyl group or a diisocyanate compound and a monomer of an acrylic ester having a hydroxyl group) A 1:1 mole ratio of adducts is subjected to an addition reaction.

In order to carry out the above reaction, it is preferable to add a small amount of a polymerization inhibitor such as hydroquinone and carry out the reaction while blowing dry air.

(2) A compound having a melting point of 0 to 250°C and having a radically polymerizable unsaturated group. Specific examples include stearyl acrylate, stearyl methacrylate, triacrylic anurate, cyclohexanediol diacrylate, cyclohexanediol dimethacrylate, spiroglycol diacrylate, and spiroglycol diacrylate.

In addition, in the present invention, the above (1) and (2) can be used as a mixture, and in contrast, the radically polymerizable unsaturated monomer improves the crosslinking density when irradiated with ionizing radiation. It improves heat resistance, and in addition to the above-mentioned monomers, ethylene glycol diacrylate, ethylene glycol dimethacrylate, polyethylene glycol diacrylate, polyethylene glycol dimethacrylate, hexanediol diacrylate, hexanediol diacrylate, trimethylol Propane triacrylate, trimethylolpropane trimethacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, pentaerythritol triacrylate, pentaerythritol trimethacrylate, dipentaerythritol hexaacrylate, dipentaerythritol hexamethacrylate, ethylene glycol diglycidyl ether di Acrylate, ethylene glycol diglycidyl ether dimethacrylate, polyethylene glycol diglycidyl ether diacrylate, polyethylene glycol diglycidyl ether dimethacrylate, propylene glycol diglycidyl ether diacrylate, propylene glycol diglycidyl ether dimethacrylate, polypropylene glycol diglycidyl ether diacrylate,
Polypropylene glycol diglycidyl ether dimethacrylate, sorbitol tetraglycidyl ether tetraacrylate, sorbitol tetraglycidyl ether tetramethacrylate, etc. can be used, and based on 100 parts by weight of the solid content of the above copolymer mixture,
It is preferably used in an amount of 0.1 to 100 parts by weight.

In addition, the above substances can be sufficiently cured by electron beam irradiation, but when curing by ultraviolet irradiation, benzoin ethers such as benzoquinone, benzoin, and benzoin methyl ether, halogenated acetophenones, and biacyl are used as sensitizers. It is also possible to use materials that generate radicals when irradiated with ultraviolet rays, such as the following.

The layer consisting of an ionizing radiation-curable resin is formed by applying an ionizing radiation-curing resin diluted with a solvent to the base sheet by flow coating, roll coating, gravure coating, etc., and then scattering the solvent by heat drying to form a solid film. Form.

Typical examples of ionizing radiation are electron beams and ultraviolet rays. The former is emitted from various electron beam accelerators such as Kotscroft-Walton type, Bumpgraph type, resonant transformer type, insulated core transformer type, linear type, Guinamicron type, and high frequency type.
~100Q K e V, preferably 100-300K
An electron beam with energy in the eV (D range) is used.

The latter uses ultraviolet light emitted from sources such as ultra-high-pressure mercury lamps, high-pressure mercury lamps, low-pressure mercury lamps, carbon arcs, xenon arcs, or metal halide lamps.

The ionizing radiation irradiation is performed after the uncured ionizing radiation-cured resin is embossed.

However, as long as it is applied after embossing, it may be selected either before or after forming the printing layer.

Further, the ionizing radiation is irradiated from the base film side and from the ionizing radiation curing resin side or the printing layer side, considering the above-mentioned irradiation timing. However, irradiation may be performed from both sides with the base film on one side.

The printing layer consists of a release layer, a pattern layer and an adhesive layer.

The release layer plays a role in providing abrasion resistance and printability, and is made of, for example, acrylic, vinyl chloride-vinyl acetate copolymer, polyester, polyvinyl butyralide,
Select and use from chlorinated rubber, rubber, polyamide, urethane, etc.

The pattern layer is made of, for example, styrene resins such as ethyl cellulose, ethyl hydroxycellulose, cellulose acetate propionate, cellulose acetate derivatives, polystyrene, polyα-methylstyrene, styrene copolymer resins, polymethyl methacrylate, polyethyl methacrylate, and polyacrylic. Acrylic or methacrylic resin alone or copolymer resin such as ethyl acid, butyl polyacrylate, rosin,
One type of rosin-modified phenolic resin, rosin ester resin such as polymerized rosin, polyvinyl acetate resin, chroman resin, vinyl toluene resin, vinyl chloride resin, polyester resin, polyurethane resin, butyral resin, shellac, gum arabic, acaroid, mastic, etc. Two or more types can be selected and used.

The adhesive layer is made of, for example, rubber resin such as polyisoprene rubber, polyisobutyl rubber, styrene butadiene rubber, butadiene acrylonitrile rubber, (meth)acrylic acid ester resin, polyvinyl ether resin, polyvinyl acetate resin, vinyl chloride-acetic acid resin, etc. The resin is selected from vinyl copolymer resins, polystyrene resins, polyester resins, polyamide resins, polychlorinated olefin resins, polyvinyl butyral resins, and the like.

The pattern layer and the adhesive layer are selected from those that are compatible with the release layer and the resin that is the material of the molded product.

The printing layer is printed using conventional printing inks such as gravure,
Select from printing methods such as flow coater, screen, and flexible printers.

Suitable materials for the vehicle used in the printing layer include acrylic resins, vinyl chloride-vinyl acetate copolymer resins, urethane resins, butyral resins, polyesters, cellulose resins, and the like.

Further, a vapor deposition layer may be further provided as necessary.

The material for the molded product may be any synthetic resin that can be injection molded; typical examples include polystyrene, acrylic resin, As resin, ABS resin, polycarbonate, polyphenylene ether, polyamide, polyether sulfone, polyetherimide, Select from polyetherketone, polymethylpentene, polybutylene terephthalate, polyethylene terephthalate, polypropylene, polyethylene, etc.

[Example 1] Example 1 will be described using the drawings.

FIG. 1 is a cross-sectional view of a composite release sheet before embossing, in which a polyester film (A2220 manufactured by Toyobo Co., Ltd.) is used as the base film 2, and an ultraviolet curable resin is used as the ionizing radiation curable resin 3. (HARDIC manufactured by Dainippon Ink & Chemicals) by reverse coating method.
It was applied to a thickness of μm and dried at 80° C. for 20 seconds.

Fine embossing was performed on the exposed surface of the uncured ultraviolet curable resin layer on the above composite sheet using an embossing plate having parallel lines with a pitch of 50 μm and a depth of 10 μm.

Next, output 8QW/cm from the embossed surface side.
1 at a position of 15 cm under an ozone-containing high-pressure mercury lamp.
The release layer was cured by irradiating ultraviolet rays for 0 seconds.

Through the above steps, a composite releasable sheet 1' having moldability and having a cross section as shown in FIG. 2 was produced.

A release layer 4 of acrylic resin is applied by gravure coating onto the obtained release sheet 1', and then a picture is printed by screen printing using an ink containing an acrylic resin and vinyl chloride-vinyl acetate copolymer as a vehicle. An If'i layer 5 and an adhesive layer 6 were formed to obtain a transfer foil.

A cross-sectional view of the transfer foil is shown in FIG.

After placing the transfer foil in an injection mold and injecting the As resin, the composite releasable sheet 1' was peeled off.

The molded product obtained was rich in color and had a fine uneven pattern.

[Example 2] Same as Example 1, a polyester film (A2220 manufactured by Toyobo @) was used as the base film 2 and an ultraviolet curable resin (HARDIC manufactured by Dainippon Ink & Chemicals @) was used as the ionizing radiation curable resin 3. The prepared transfer foil was placed in an injection mold, ABS resin was injected, and the composite releasable sheet 1' was peeled off.

The obtained molded product had fine irregularities and was excellent in design.

[Operation and effects of the invention]

By embossing a composite release sheet containing an ionizing radiation-curable resin from the side of the ionizing radiation-curable resin, which is a thermoplastic solid in its uncured state, and then irradiating it with ionizing radiation, it is possible to create a mold release sheet that has not been previously possible. A releasable sheet was obtained that was strong and had sharp irregularities.

Furthermore, when this mold release sheet is applied to transfer foil and molded, there is no need to use a mold, and because it has excellent heat resistance, it is possible to produce molded products with sharper unevenness than conventional products at a low cost. was gotten.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of the composite releasable sheet before embossing. FIG. 2 is a cross-sectional view of a composite releasable sheet having moldable properties, which is strongly cured by irradiating ionizing radiation after embossing the ionizing radiation S-cured resin layer. FIG. 3 shows a release layer on the composite release sheet shown in FIG.
FIG. 2 is a cross-sectional view of a transfer foil having a pattern layer and an adhesive layer. 1. Composite release sheet (unprocessed, uncured), 2. Base film, 3. Ionizing radiation curable resin layer (uncured state)
, 1' composite release sheet (processed and cured), 3' ionizing radiation curable resin layer (embossed and cured), 4 release layer, 5 pattern layer, 6 adhesive layer Fig. 1, 2t! 1 Figure 3

Claims (4)

[Claims] (1) A releasable sheet characterized by having an ionizing radiation-curable resin layer having irregularities on a base film. (2) A transfer foil characterized in that a release layer, a pattern layer, and an adhesive layer are sequentially provided on the release sheet according to claim (1). (3) Forming an ionizing radiation-curable resin layer, which is a thermoplastic solid in an uncured state, on the base film, embossing the resin layer, and then irradiating the ionizing radiation-curable resin with ionizing radiation. Claim (1) comprising curing the layer.
) method for producing a releasable sheet. (4) In claim (3), from the step of sequentially forming a release layer, a pattern layer, and an adhesive layer after embossing, and then curing the ionizing radiation-curable resin layer by irradiating with ionizing radiation. The method for producing a transfer foil according to claim (2).