JPH11170784A - Transfer sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the wear-resistance after a transfer by a method wherein a release layer is constituted of a thermoplastic resin containing a specified value or lower, by weight ratio, of a molecule having a high rigidity of an average molecular diameter specified value. SOLUTION: This transfer sheet is constituted by laminating a release layer 2, a release layer 3, a transparent resin layer 4, a decorative layer 5, and an adhesive layer 6 on a base material 1. The release layer 3 is a layer which transfers to the side of a body to be transferred after a transfer, and becomes a surface protective layer for the transfer layer, and a layer wherein a molecule with a high rigidity having an average molecular diameter of 1-10 μm, is added to a thermoplastic resin, is used. When being less than 1 μm, a wear-resistance effect is small, and when exceeding 10 μm, the transparency and printing property decrease, and it may cause void at the time of pattern printing. The content of the molecule is made 30% or lower by a weight ratio, in the thermoplastic resin. When exceeding 30%, the elongation of a coating film decreases, and does not follow the elongation of a corner is bending or the like. The transparent resin layer 4 is provided in order to improve the joint force with the release and decorative layers 3, 5 and the printing property of the decorative layer 5, and a hardening type resin is used.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer sheet used for decorating the surface of various articles.

[0002]

Conventionally, there has been a method of transferring a desired decoration layer using a transfer sheet as a means for decorating a surface of a decorative interior material or decorative miscellaneous goods. When the release layer of this transfer sheet is made of a thermoplastic resin, it has elongation and good moldability, but poor abrasion resistance and scratch resistance. Therefore, the release layer is sometimes made of a curable resin. However, in consideration of the releasability from the substrate, there is a limit to the range to be selected.

[0003] In order to improve the abrasion resistance of the transferred decorative layer, coating may be performed after the transfer. However, this method requires a large number of steps, and also involves cleaning of dirt and oil adhering to the surface of the molded product. is necessary. In particular, in the case of dip or flow coating, there are restrictions on the speed and the shape of a molded product in order to prevent bubbles, liquid dripping, and tearing from occurring. In addition, there is a problem that the solvent of the coating liquid evaporates, and new coating equipment is required.

[0004]

In order to solve the above-mentioned problems, in the present invention, the release layer is formed to have an average particle size of 1-10.
It was made of a thermoplastic resin containing 30% or less by weight of fine particles having a high hardness of μm, and a transparent resin layer to be laminated next was a curable resin. Thereby, a transfer sheet having excellent abrasion resistance can be obtained.

[0005]

FIG. 1 is a sectional view showing an example of a transfer sheet according to the present invention. As shown in the figure, this transfer sheet has a release layer 2 formed on a base material 1 and a release layer 3, a transparent resin layer 4, a decorative layer 5, and an adhesive layer 6 laminated thereon. It is.

As a substrate, a synthetic resin film of polyethylene terephthalate, polypropylene, polyethylene, polycarbonate, polystyrene, polyvinyl chloride, polyamide, or the like is used. Among these, a biaxially stretched polyethylene terephthalate film or a polypropylene film is most preferable in consideration of moldability, heat resistance, printability and the like. The thickness of the substrate is about 9 to 200 μm, preferably 16 to 100 μm. When the thickness is less than 16 μm, the strength is insufficient, and when the thickness exceeds 100 μm, it can be used for in-mold transfer. However, heat transfer is poor in roll transfer, which causes transfer failure and increases cost. .

[0007] The release layer is a layer which remains on the substrate side even after the transfer and facilitates the separation from the transfer layer, and is provided on the substrate as required. This release layer is formed on a substrate with a thickness of about 0.01 to 5 μm using melamine, silicone, aminoalkyd, urethane, urea, epoxy resin, or the like. The peel strength can be adjusted by adding an additive such as silicon, fluorine, polyester, or polyethylene. In addition, a known matting agent such as microsilica can be added to the release layer to adjust the gloss of the surface after transfer.

[0008] The release layer is transferred to the transfer object side after the transfer and becomes a surface protective layer of the transfer layer. In the present invention, the release layer is formed using a thermoplastic resin to which fine particles of high hardness are added. As the thermoplastic resin, an acrylic resin, a urethane resin, a vinyl chloride-vinyl acetate copolymer, a butyral resin, or the like is used. Among them, acrylic resin is preferable in consideration of wear resistance and transparency.

Oxide fine particles are used as the high hardness fine particles. Specifically, it is appropriately selected from silica, alumina, titanium oxide, zinc oxide, tin oxide and cerium oxide depending on the application. For example, for outdoor use, ultraviolet absorption performance is required, and therefore zinc oxide and cerium oxide are preferable. For general molding use, alumina and silica which are inexpensive are preferable. When antistatic performance is required, tin oxide is preferably used. The silicon / titanium ratio is 2 /
Oxide fine particles such as 1 may be used. The particle size of the fine particles used is 1 to 10 μm. If it is less than 1 μm, the abrasion resistance effect is small. On the other hand, if it exceeds 10 μm, the transparency and printability deteriorate. On the other hand, if the particle size is large, it causes dropping during pattern printing. The content of the fine particles is 30% or less by weight in the thermoplastic resin. If it exceeds 30%, the elongation of the coating film will decrease, and it will not follow the elongation of the corner during bending or injection molding.

It is preferable to use oxide fine particles which have been subjected to a surface treatment in order to improve the holding power in a binder, the dispersibility in an ink, and the transparency of a coated product. A silane coupling agent is generally used as the surface treatment agent, and a titanate-based coupling agent or an aluminate-based coupling agent may be selected depending on the use.

The release layer may be added with polyethylene wax, Teflon wax, carnauba wax, paraffin wax or the like as an additive in order to make the surface smooth after transfer. In addition, when used for exterior applications or areas exposed to sunlight, benzotriazole-based, benzophenone-based, salicylic acid-based ultraviolet absorbers, hindered amine-based stabilizers, phenolic antioxidants, and heat stabilizers are added. Is preferred.

The release layer is laminated by a known method such as gravure printing, roll coating, screen printing, and offset printing.

The transparent resin layer is provided for improving the adhesion between the release layer and the decorative layer and for improving the printability of the decorative layer. In the present invention, a curable resin is used as the transparent resin. As the curable resin, any of an ionizing radiation curable resin and a thermosetting resin can be used.

As the ionizing radiation-curable resin, a composition in which a prepolymer, an oligomer and / or a monomer having a polymerizable unsaturated bond or an epoxy group in a molecule is appropriately mixed is used. Examples of the prepolymer and oligomer include unsaturated polyesters such as a condensate of an unsaturated dicarboxylic acid and a polyhydric alcohol, polyester methacrylate,
Examples include methacrylates such as polyether methacrylate, polyol methacrylate, and melamine methacrylate, and acrylates such as polyester acrylate, epoxy acrylate, urethane acrylate, polyether acrylate, polyol acrylate, and melamine acrylate. Examples of the monomer include styrene,
Styrene monomers such as α-methylstyrene, acrylates such as methyl acrylate, 2-ethylhexyl acrylate, methoxyethyl acrylate, butoxyethyl acrylate, butyl acrylate, butoxybutyl acrylate and phenyl acrylate , Methyl methacrylate,
Methacrylic esters such as ethyl methacrylate, propyl methacrylate, methoxyethyl methacrylate, ethoxymethyl methacrylate, phenyl methacrylate, lauryl methacrylate, 2- (N, N-diethylamino) ethyl acrylate, methacrylic acid-2 -(N, N-dimethylamino) ethyl, 2- (N, N-dibenzylamino) ethyl acrylate, (N, N-dimethylamino) methyl methacrylate, 2- (N, N-dimethyl acrylate) Substituted amino alcohol esters of unsaturated acids such as diethylamino) propyl, unsaturated carboxamides such as acrylamide and methacrylamide, ethylene glycol diacrylate, propylene glycol diacrylate, neopentyl glycol diacrylate, 1,6-hexadioldia Kurire Compounds such as diethylene glycol diacrylate and triethylene glycol diacrylate, polyfunctional compounds such as dipropylene glycol diacrylate, ethylene glycol acrylate, propylene glycol dimethacrylate, diethylene glycol dimethacrylate, and / or two or more in the molecule And polythiol compounds having a thiol group such as trimethylolpropanetrithioglycolate, trimethylolpropanetrithiopropylate, and pentaerythritol tetrathioglycol.

One or two of the above compounds may be used if necessary.
The prepolymer or oligomer is used in an amount of 5% by weight or more and the monomer and / or polythiol is used in an amount of 9% or more in order to impart ordinary coating suitability to the resin composition.
It is preferable that the content be 5% by weight or less.

In selecting a monomer, if the flexibility of the cured product is required, the amount of the monomer may be reduced as long as the coating suitability is not impaired, or a monofunctional or bifunctional acrylate monomer may be used. And a structure with a relatively low crosslink density. Also,
When the heat resistance, hardness, solvent resistance, etc. of the cured product are required, increase the amount of the monomer within a range that does not affect coating suitability, or use a trifunctional or higher functional acrylate monomer. Preferably, the structure has a high crosslinking density. 1,2 functional monomer and 3
It is also possible to adjust the suitability for coating and the physical properties of the cured product by mixing monomers having functionalities or higher. As the monofunctional acrylate monomer as described above, 2-hydroxyacrylate, 2
-Hexyl acrylate, phenoxyethyl acrylate and the like. Examples of the bifunctional acrylate monomer include ethylene glycol diacrylate and 1,6-hexanediol diacrylate, and examples of the trifunctional or higher acrylate monomer include trimethylolpropane triacrylate, pentaerythritol hexaacrylate, and dipentane. Erythritol hexaacrylate and the like.

In order to control physical properties such as flexibility and surface hardness of the cured product, the following non-ionizing radiation curable resin is used for at least one of the above prepolymers, oligomers and monomers. It can be used in a mixture of 1 to 70% by weight, preferably 5 to 50% by weight. As ionizing radiation non-curable resins, urethane-based, cellulose-based, polyester-based,
Thermosetting resins such as acrylic, butyral, polyvinyl chloride, and polyvinyl acetate can be used, and in particular, cellulose, urethane, and butyral are preferable from the viewpoint of flexibility.

In particular, in the case of curing with ultraviolet rays, the ionizing radiation-curable resin composition may contain, as a photopolymerization initiator, acetophenones, benzohenones, Michler benzoyl benzoate, α-amyloxime ester, tetramethyl melium monosulfide, Thioxanthones, and / or
Alternatively, n-butylamine, triethylamine, tri-n-butylphosphine and the like can be mixed and used as a photosensitizer.

The term "ionizing radiation" as used herein means an electromagnetic wave or a charged particle beam having an energy quantum capable of polymerizing and cross-linking molecules, and is usually an ultraviolet ray or an electron beam. As the ultraviolet light source, a light source such as an ultra-high pressure mercury lamp, a high pressure mercury lamp, a low pressure mercury lamp, a carbon arc, a black light lamp, and a metal halide lamp is used. As the electron beam source, various electron beam accelerators such as Cockloft-Walton type, Bande graph type, Resonant transformer type, Insulated core transformer type, or linear type, Dynamitron type and high frequency type are used.
00 to 1000 keV, preferably 100 to 300 keV
Irradiate electrons with V energy.

As the thermosetting resin, a phenol resin,
There are urea resin, diallyl phthalate resin, melamine resin, guanamine resin, unsaturated polyester resin, polyurethane resin, epoxy resin, amino alkyd resin, melamine / urea co-condensation resin, silicon resin, polysiloxane resin, etc. According to the above, a curing agent such as a crosslinking agent and a polymerization initiator, a polymerization accelerator, a solvent, a viscosity modifier, an extender and the like are added. As a curing agent, isocyanates are usually used in unsaturated polyester resins and polyurethane resins, amines are used in epoxy resins, peroxides such as methyl ethyl ketone peroxide, and radical initiators such as azobisisobutyronitrile are used in unsaturated polyester resins. Often used for resin series. As the isocyanate, a divalent or higher valent aliphatic or aromatic isocyanate can be used.
Aliphatic isocyanates are desirable from the viewpoint of weather resistance. Specific examples include tolylene diisocyanate, xylene diisocyanate, 4,4-diphenylmethane diisocyanate, hexamethylene diisocyanate, lysine diisocyanate, and the like.

Further, in order to accelerate the curing reaction, if necessary, heating may be performed after coating. For example, in the case of an isocyanate-cured urethane-curable unsaturated polyester-based resin or a polyurethane-based resin, the temperature is usually about 40 to 60 ° C. for about 1 to 5 days.
It is about 1 to 300 minutes at 50 ° C.

When a picture is formed as a decorative layer, an ink in which a coloring agent such as a pigment or a dye, a diluting solvent, and, if necessary, various additives are mixed in a resin binder is used. The resin binder is selected from acrylic resin, vinyl chloride / vinyl acetate copolymer, polyester resin, cellulose resin, urethane resin, and the like. In addition, a vapor deposition layer may be provided as a decoration layer. Further, as a functional layer in addition to the decorative layer, an antistatic layer, an infrared blocking layer, an ultraviolet absorbing layer, and the like may be provided.

The adhesive layer is a layer for transferring and adhering the transfer layer to the object to be transferred. In the present invention, a heat-sensitive adhesive is used.
Specifically, gravure printing of at least one resin selected from acrylic resin, vinyl chloride / vinyl acetate copolymer, polyester resin, styrene resin, chlorinated polypropylene resin, polyamide resin, urethane resin, epoxy resin, etc. Lamination is performed using a known method such as offset printing, roll coating, and screen printing.

[0024]

Embodiments of the present invention will be described below in detail.

(Example 1) A 25 μm-thick polyester film (manufactured by Diafoil) was used as a release substrate, and a release ink having the following composition A was applied to the substrate after drying, and the coating amount was 8 to 10 g / m ^2. And dried to form a release layer.

[Composition A] Acrylic resin 50 parts by weight Polyethylene wax 2 parts by weight Silica (particle size 5-7 μm) 5 parts by weight MEK 100 parts by weight Toluene 100 parts by weight

Next, a gravure ink having the following composition B was gravure coated to a thickness of 4 g / m ² after drying to form a transparent resin layer.

[Composition B] Acrylic resin 35 parts by weight Multifunctional acrylate 15 parts by weight MEK 100 parts by weight Toluene 100 parts by weight

Next, a wood-grain decorative layer was formed with a gravure ink ("BCT" manufactured by Showa Ink) using an acrylic resin and a vinyl chloride / vinyl acetate copolymer as a binder. Subsequently, after drying a polyamide-based adhesive (manufactured by Showa Ink) at a coating amount of 2 g / m ² and gravure coating to form an adhesive layer, an electron beam was irradiated at 165 kV and 6 Mrad to obtain a transfer sheet.

(Example 2) A release ink having the following composition C was dried on the same release substrate as in Example 1 and then coated in an amount of 4 to 5 g.
/ M ² to form a release layer.

[Composition C] Acrylic resin 50 parts by weight Polyethylene wax 2 parts by weight Silica (5 to 7 μm) 15 parts by weight MEK 100 parts by weight Toluene 100 parts by weight

Next, a transparent resin layer similar to that of Example 1 was formed, and a decorative layer and an adhesive layer similar to that of Example 1 were laminated. Then, an electron beam was irradiated under the same conditions as in Example 1 and transferred. I got a sheet.

(Example 3) The release ink having the composition C was dried on the same release material as in Example 1 and the applied amount was 8 to 10 after drying.
g / m ² to form a release layer by gravure coating, a transparent resin layer similar to that of Example 1 was formed, and a decorative layer and an adhesive layer similar to that of Example 1 were further laminated. The line was irradiated under the same conditions as in Example 1 to obtain a transfer sheet.

(Example 4) A release ink having the composition C was dried on the same release substrate as in Example 1 and dried to a film thickness of 8 to 10 g.
/ M ² to form a release layer, followed by gravure coating of urethane and an isocyanate-based thermosetting resin to form a transparent resin layer. Then, after the same pattern layer and adhesive layer as in Example 1 were laminated on the transparent resin layer, an electron beam was irradiated under the same conditions as in Example 1 to obtain a transfer sheet.

Comparative Example A transfer sheet was obtained by sequentially laminating the same release layer, decorative layer, and adhesive layer as in Example 1 on the same releasable substrate as in Example 1. No transparent resin layer was formed.

(Evaluation of Performance) The performance of the transfer sheets obtained in Examples 1 to 4 and Comparative Example was evaluated. First, printability was evaluated from the printing state at the time of forming the picture layer. Next, after each transfer sheet was transferred to a wood substrate (MDF) by a roll transfer machine (manufactured by Navitas), the performance of steel wool resistance was visually evaluated. Table 1 shows the results.

[0037]

[Table 1]

As can be seen from Table 1, the transfer sheets of Examples 1 to 4 have good printability and also have excellent steel wool resistance after transfer, whereas the transfer sheets of Comparative Examples both have a little. Was inferior.

[0039]

As described above, in the transfer sheet of the present invention, the release layer is made of a thermoplastic resin and contains high-hardness fine particles having an average particle size of 1 to 10 μm. By setting the transparent resin layer to be laminated on the cured resin, the releasability of the base material and the release layer during transfer is good, and the release layer and the transparent resin layer are combined to improve the abrasion resistance after transfer. Excellent things can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of a transfer sheet according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Base material 2 Release layer 3 Release layer 4 Transparent resin layer 5 Decorative layer 6 Adhesive layer

Claims (5)

[Claims] 1. A transfer sheet having at least a release layer and a transparent resin layer on a substrate having release properties, wherein the release layer contains 30% or less by weight of high-hardness fine particles having an average particle size of 1 to 10 μm. A transfer sheet, wherein the transparent resin layer is made of a curable resin. 2. The high-hardness fine particles are Si, Al, Ti, Z
The transfer sheet according to claim 1, wherein the transfer sheet is one or more kinds of oxide fine particles selected from n, Sn, and Ce. 3. The transfer sheet according to claim 1, wherein the fine particles have a spherical shape. 4. The transfer sheet according to claim 1, wherein the transparent resin layer is made of an ionizing radiation curable resin. 5. The transfer sheet according to claim 1, wherein the transparent resin layer is made of a thermosetting resin.