JPH0811420A - Transfer sheet - Google Patents

Abstract

PURPOSE:To provide a transfer sheet excellent in flexibility and surface scratch resistance after transfer. CONSTITUTION:In a transfer sheet wherein at least an ionizing radiation curable resin protective layer and a pattern layer are provided on a releasable support sheet as transfer layers in this order, the ionizing radiation curable resin protective layer contains a non-crosslinking type thermoplastic acrylic resin with an average mol.wt. of 50000-600000 and glass transition temp. of 50-130 deg.C and a prepolymer having two or more acryloyl or methacryloyl groups in one molecule thereof and the pattern layer contains a noncrosslinking type thermoplastic acrylic resin with an average mol.wt. of 50000-600000 and glass transition temp. of 50-130 deg.C.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to home appliances and furniture.
The present invention relates to a hard coat (hard coating film) transfer sheet used for the purpose of surface protection and surface makeup of interior materials for construction, vehicle interior materials such as automobiles.

[0002]

2. Description of the Related Art Conventionally, in such a transfer sheet, it has been proposed to use various crosslinking and hardening materials as a protective layer on a releasable substrate sheet. As one of them, JP-B-59-20464 describes a so-called thermosetting type transfer layer comprising a polymer material having a hydroxyl group and a cross-linking agent having a blocked isocyanate group. It is. This is a thermal transfer decorative material consisting of a lacquer layer / at least one pattern printing layer / an adhesive layer that can be activated by heating, with a transfer label containing a substance which reacts with at least one of these layers and crosslinks between them. Yes, the transferred surface is heat resistant and is also resistant to chemicals, abrasion and abrasion.
Further, in the dry release transfer consisting of a carrier sheet / design layer described in JP-B-61-3272, the design layer is a solid cross-linked polymer formed by photopolymerization of liquid ink, The ink contains one or more ethylenically unsaturated monomers and a prepolymer having an acryloyl group or a methacryloyl group as a side group or a terminal group, and photopolymerization is performed by irradiating the entire liquid ink layer with actinic rays or electron beams. Done by. 50 to 500 with a ballpoint pen, pencil or iron brush from the carrier sheet surface of this dry release transfer.
With the pressure of g, the design layer is peeled off and transferred to a non-transferring body such as paper. The transfer layer, which is the design layer, is not brittle and has a minimum elongation at break of 0.5%. Furthermore, Japanese Patent Fairness 5-4
In the transfer sheet comprising a release sheet / protective layer described in Japanese Patent No. 9480, the vehicle of the protective layer, which is the transfer layer, has a glass transition point of 0 to 250 ° C. and a radically polymerizable unsaturated group in the polymer. , Melting point 0-250 ℃
And a compound having a radically polymerizable unsaturated group, and a compound obtained by adding a bifunctional or higher functional acrylate monomer to the above and / or, specifically, a crosslinkable polymethyl methacrylate and a hexanediol acrylate (monomer), The transferred pattern layer has excellent physical properties and chemical properties.

[0003]

[Problems to be solved by the invention] Japanese Patent Publication No. 59-2046
As described in No. 4, in the case of a thermosetting type transfer layer using a polymeric material having a hydroxyl group and a cross-linking agent of blocked isocyanate, the surface of the transferred body after transfer is heat resistant, It has chemical resistance and abrasion resistance, but requires a heating step for crosslinking and curing during manufacturing. As a result, since the transfer sheet itself is deformed, the transfer to the transfer target cannot be performed well, and such heat curing requires 40 to 60 ° C. and about 3 to 5 days, There was a problem with poor productivity.

Further, as described in JP-B-61-3272, 1 having an acryloyl group or a methacryloyl group
In the case of a transfer layer consisting of a design layer formed by photopolymerization of a liquid ink containing one or more ethylenically unsaturated monomers and a prepolymer by irradiation with actinic rays or electron rays, irradiation with actinic rays or Since it is cured by electron beam irradiation, there is no damage due to heat during the manufacturing process compared with heat curing, and the time required for curing is short within a few seconds, but it is intended for partial transfer with a writing brush etc. Therefore, when the transfer is performed so as to cover a large area of the transferred material having unevenness, the densely crosslinked transfer layer itself is liable to crack due to lack of physical properties of elongation,
There is a problem in that breakage occurs and good transfer cannot be performed.

Further, as described in JP-B-5-49480, as an example of a vehicle for a protective layer, a transfer comprising a crosslinkable polymethylmethacrylate polymer having a radically polymerizable unsaturated group and a bifunctional or higher functional acrylate monomer. When the layer is used, it is characterized in that it is solid and thermoplastic at room temperature in the uncured state and is cured by ionizing radiation after transfer. Therefore, even when it is used in the application such as the injection molding simultaneous transfer method in which the transfer layer is largely deformed during the transfer, the transfer layer is not cracked. However, there is a problem that the crosslink density is low and the surface hardness after transfer is not sufficient.

Therefore, the present invention is capable of curing a hard coating film in a short time, and has excellent flexibility and scratch resistance of the surface after transfer during the transfer sheet manufacturing process and during the use of the transfer sheet. It is to provide an excellent transfer sheet.

Further, in the present invention, the ionizing radiation-curable resin layer of the transfer layer is non-adhesive at room temperature in the uncured state, and is directly continuous without undergoing steps such as crosslinking and curing during the production of the transfer sheet. Another object of the present invention is to provide a transfer sheet which can be coated with an upper layer such as a pattern layer or an adhesive layer, and can be used before or after transfer when the transfer sheet is irradiated with ionizing radiation.

[0008]

In order to solve the above problems, in the transfer sheet of the present invention, at least an ionizing radiation curable resin protective layer and a pattern layer are formed as a transfer layer on the releasable substrate sheet. In the transfer sheet which has in order,
The ionizing radiation-curable resin protective layer has an average molecular weight of 5,000.
0 to 600,000, a glass transition temperature of 50 to 130 ° C., a non-crosslinking type thermoplastic acrylic resin and a prepolymer having two or more acryloyl groups or methacryloyl groups in one molecule, and the picture layer has an average molecular weight of 50,000. ~ 6
A transfer sheet characterized by containing a non-crosslinked thermoplastic acrylic resin having a glass transition temperature of 50 to 130 ° C. .

As the material of the base sheet, a polyester resin film such as polyethylene terephthalate, polybutylene terephthalate, ethylene terephthalate / isophthalate copolymer, or the like, a release resin such as polyolefin such as polyethylene or polypropylene, or a silicone resin is applied. The coated paper used is 10 μm to 2 in thickness.
Those having a size of about 00μ can be used. Also, if necessary,
A release layer may be further formed on the resin film by using silicon resin, melamine resin, polyolefin or the like. Incidentally, the release layer referred to in the present invention, the release layer at the interface with the protective layer at the time of transfer, closely adhered to the releasable substrate sheet side,
The layer that is removed together with the releasable substrate sheet.

Furthermore, when it is desired to impart a desired matte or uneven pattern to the surface of the protective layer after transfer, an uneven pattern of the same shape as the desired unevenness is formed on the surface of the substrate sheet or the release layer. You may form. Such uneven patterns include matte, hairline, wood grain conduit, parallel groove, diffraction grating, hologram and the like.

The non-crosslinking type thermoplastic acrylic resin which is a constituent component of the ionizing radiation curable resin protective layer includes (meth)
Acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, n-propyl (meth) acrylate, isopropyl (meth) acrylate, (meth) acrylic acid-n
-Butyl, isobutyl (meth) acrylate, (meth) acrylic acid-n-amyl, (meth) acrylic acid-n-hexyl, (meth) acrylic acid-n-octyl, (meth) acrylic acid lauryl etc. ) Alkyl halides of (meth) acrylic acid such as acrylic acid alkyl ester, (meth) acrylic acid-2-chloroethyl, and (meth) acrylic acid-3-chloropropyl, (meth) acrylic acid-2
-Hydrogenated compounds such as (meth) acrylic acid ester having OH group such as hydroxyethyl, (meth) acrylic acid-2-hydroxypropyl, methyl α-chloro (meth) acrylate, ethyl α-chloro (meth) acrylate, etc. Α-Alkyl (meth) acrylic acid ester having an OH group such as (meth) acrylic acid ester and (meth) acrylic acid-1-chloro-2-hydroxyethyl, and (meth) acrylic acid such as glycidyl (meth) acrylate 1 of the system monomers
It is possible to use a homopolymer or a copolymer composed of two or more kinds, and having an average molecular weight of 50,000 to 600,000 and a glass transition temperature of 50 to 130 ° C, preferably a glass transition temperature of 80 to 110 ° C. In this specification, the term (meth) acrylate is used to mean acrylate or methacrylate.

When the average molecular weight is 50,000 or less, the scratch resistance of the ionizing radiation-curable resin protective layer after curing is extremely reduced. On the other hand, when the average molecular weight is 600,000 or more, the elongation of the ionizing radiation-curable resin protective layer at the time of transfer is reduced, and therefore the deformation at the time of transfer causes cracking of the protective layer. Further, when the glass transition temperature is 50 ° C. or lower, the scratch resistance after curing of the ionizing radiation-curable resin protective layer is extremely lowered, and after solvent drying, non-adhesiveness in an uncured state (touch-drying). Sex) is insufficient. On the other hand, when the glass transition temperature is 130 ° C. or higher, the elongation of the ionizing radiation curable resin protective layer at the time of transfer decreases.

The prepolymer which is a constituent of the ionizing radiation-curable resin protective layer is a prepolymer which can be crosslinked by ionizing radiation and has a molecular weight of 100 to 100 having two or more acryloyl groups or methacryloyl groups in one molecule.
00, more preferably 100 to 5000.
Specifically, (meth) acrylates such as polyester (meth) acrylate, urethane (meth) acrylate, epoxy (meth) acrylate, melamine (meth) acrylate, and silicon (meth) acrylate can be used. When the molecular weight is less than the above lower limit, the cured protective layer lacks in elongation and flexibility, and when the molecular weight exceeds the above upper limit, the cured protective layer has insufficient scratch resistance. Among these, urethane (meth) acrylate having both elongation at transfer and scratch resistance of the surface after transfer is preferable. Although both acrylate and methacrylate can be used, acrylate is faster in terms of cross-linking and curing speed with ionizing radiation, and therefore acrylate is more advantageous for the purpose of efficiently forming a hard coating film at high speed in a short time. is there.

The content of the prepolymer in the ionizing radiation-curable resin of the present invention is preferably 30 to 90 parts by weight based on 100 parts by weight of the acrylic resin.
Here, if the amount of the prepolymer is 30 parts by weight or less, the crosslinking density of the ionizing radiation-curable resin protective layer due to ionizing radiation becomes extremely coarse, the strength of the protective layer itself is insufficient, and the scratch resistance decreases. On the other hand, when the amount of the prepolymer is 90 parts by weight or more, the non-adhesiveness of the coating film in the uncured state after solvent drying becomes insufficient. Further, since the cross-linking density of the ionizing radiation-curable resin protective layer due to ionizing radiation becomes too dense, the elongation rate of the protective layer itself decreases, and deformation, breakage, cracks and the like occur during transfer.

In the ionizing radiation-curable resin protective layer,
When curing with ultraviolet light, as a photopolymerization initiator,
Acetophenones, benzophenones, Michler benzoyl benzoate, thioxanthones, etc. can be mixed and used. In addition, if necessary, waxes such as wax, polyethylene wax, montan wax, etc., inorganic fine powder such as calcium carbonate, alumina, silica, barium sulfate, etc., resin beads such as acrylic beads, urethane beads, polycarbonate beads, etc. Filler,
A volatile diluent solvent such as an organic solvent and a colorant such as a dye or a pigment may be added. Further, as the reactive diluent, a (meth) acrylic monomer having one or more acryloyl groups or methacryloyl groups in one molecule may be added. Examples of such monomers are:
There are trimethylolpropane tri (meth) acrylate, dipentaerythritol hexa (meth) acrylate, dipentaerythritol penta (meth) acrylate and the like. However, particularly when the elongation and flexibility of the protective layer are increased, or when the non-tackiness of the coating film during solvent drying and uncuring is particularly important, it is preferable not to add a reactive diluent. preferable.

For coating the ionizing radiation-curable resin composition, various known methods such as gravure coating, gravure reverse coating, gravure offset coating, roll coating, reverse roll coating, knife coating, wire bar coating, and flow. A coat, a comma coat, a dip coat, a Wheeler coat, a spinner coat, a spray coat, a silk screen, a pouring coat, a brush coat and the like are applied, and the coating thickness is about 0.1 to 100 μm when dried.

The ionizing radiation means an electromagnetic wave or a charged particle beam having an energy quantum capable of polymerizing and cross-linking molecules, and includes visible rays, ultraviolet rays (near ultraviolet rays, vacuum ultraviolet rays, etc.), X-rays, electron beams and the like. is there. Usually, ultraviolet rays or electron beams are used. As the ultraviolet ray 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 can be used.
As the wavelength of ultraviolet rays, a wavelength range of 1900 to 3800Å is usually mainly used. Electron beam sources include Cockloft-Walton type, Van de Graft type, Resonant transformer type,
Insulation core transformer type, linear type, dynamitron type, high frequency type electron beam accelerators, etc.
Those which irradiate with electrons having an energy of 000 KeV, preferably 100 to 300 KeV can be used. Upon irradiation with ionizing radiation, the ionizing radiation curable resin undergoes a cross-linking polymerization reaction and changes into a three-dimensional polymer structure. Such a change is called hardening. The ionizing radiation may be irradiated at the time of manufacturing the transfer sheet, which is before the transfer to the transfer target, or after the transfer. In the method in which the protective layer is transferred in the non-adhesive non-cured state, and is then irradiated and cured, the protective layer is transferred in a state where it still has large flexibility and thermoplasticity. Therefore, such a method is especially applicable to the injection molding simultaneous transfer method, the vacuum molding simultaneous transfer method,
Alternatively, it is suitable for application to a transfer method such as a lapping simultaneous transfer method in which a transfer sheet is deformed into a three-dimensional shape during transfer.

As the pattern layer, a resin vehicle is used as a pattern layer ink in which a colorant such as a pigment or a dye, and if necessary, an extender pigment, a stabilizer, a solvent and the like are appropriately mixed. The pattern layer is formed by a known printing method such as gravure printing, silk screen printing, offset printing or a coating method using the pattern layer ink. The pattern is arbitrary such as a wood grain pattern, a stone grain pattern, letters, figures, a solid layer, or a combination thereof.

The vehicle in the pattern layer has an average molecular weight of 50,000 to 600,000 and a glass transition temperature of 50.
Contains an acrylic resin that is ~ 130 ° C. As this acrylic resin, one kind or two or more kinds can be selected and used from those described as the components of the ionizing radiation-curable resin protective layer. The vehicle may be the acrylic resin alone, but is preferably mixed with another resin in order to improve printability, adhesion to the adhesive layer or the body to be transferred, and the like. Examples of the resin used by mixing include vinyl chloride, vinyl chloride vinyl acetate copolymer, vinyl polymer such as vinyl acetate, cellulose derivative such as cellulose acetate and cellulose nitrate, polyurethane resin, polyester resin and the like. . When the acrylic resin is contained in the pattern layer in an amount of 20% by weight or more, the adhesion with the ionizing radiation-curable resin protective layer, the elongation during transfer, and the transfer layer strength after transfer can be improved. When the content in the pattern layer is less than 20% by weight, the adhesion between the protective layer and the pattern layer is lowered, and in some cases, peeling or cracking between layers occurs, and whitening occurs on the surface.

In the constitution of the present invention, the transfer layer, that is, the layer which is transferred from the releasable substrate sheet to the transferred material during transfer is
It is a minimum protective layer and a pattern layer. However, in addition to these, an antistatic layer, an adhesive layer, and the like can be laminated if necessary.

In the constitution of the present invention, an adhesive can be provided on the ionizing radiation-curable resin protective layer or on the pattern layer, and is a layer for transferring and adhering the transfer layer to the transferred material. Can be selected from among heat-sensitive adhesives, pressure-sensitive adhesives, solvent-activated adhesives, ionizing radiation-curable adhesives, etc. according to the application. The adhesive layer may be omitted when the transfer layer itself other than the adhesive layer such as the pattern layer and the peeling layer has sufficient adhesiveness, or when the adhesive layer is provided on the transfer target side.

The heat-sensitive adhesive exhibits adhesiveness by heating, and a thermoplastic resin, an ionomer or the like which is melted by heat to develop an adhesive force is usually used. Examples of the thermoplastic resin include cellulose nitrates, cellulose derivatives such as cellulose acetate, polystyrene, styrene resins such as poly α-methylstyrene or styrene copolymers, poly (meth) acrylate methyl, poly (meth) acrylate ethyl. Acrylic resin such as, vinyl chloride vinyl acetate copolymer, vinyl polymer such as ethylene vinyl alcohol copolymer, rosin, rosin ester resin such as rosin-modified maleic acid resin, natural such as polyisoprene rubber, styrene-butadiene rubber, or , Synthetic rubbers, and various ionomers are used. In addition, a thermosetting resin that causes cross-linking polymerization, addition polymerization, etc. by heat to be cured to develop an adhesive force is also used as a heat-sensitive adhesive. As the thermosetting resin, for example, epoxy resin, polyurethane resin, phenol resin or the like is used.

As the pressure-sensitive adhesive, any of the pressure-sensitive adhesives conventionally used for pressure-sensitive adhesive tapes and seals can be used.
For example, rubber-based resins such as polyisoprene rubber, polyisobutyl rubber, styrene-butadiene rubber, and butadiene acrylonitrile rubber, (meth) acrylic acid ester-based resins, polyvinyl ether-based resins, polyvinyl acetate-based resins, polyvinyl chloride / vinyl acetate-based resins. A suitable tackifier, coumarone-indene resin, etc. are added in an appropriate amount to an arbitrary resin system containing, as a main component, one or a mixture of two or more polymers such as polymer resins and polyvinyl butyral resins. Furthermore, if necessary, a softening agent, a filler, an antiaging agent, a crosslinking agent, etc. are added.

As the transferred material, acrylic resin, polycarbonate, acrylonitrile butadiene styrene copolymer (ABS), resin such as phenol resin, metal such as iron, copper and aluminum, glass, earthenware, ceramics, cement,
Various materials such as ceramics such as calcium silicate, wood alone, wood such as plywood, and perch crude can be targeted. The form of the transferred body is a flat plate, a curved plate, a columnar body, a sheet, various three-dimensional shaped molded products, and the like.

When the antistatic layer is provided as an independent layer, it is provided between the protective layer and the adhesive layer, between the protective layer and the decorative layer,
It is provided between the decorative layer and the adhesive layer other than the outermost surface of the protective layer.
This is because the physical properties of the protective layer such as scratch resistance and chemical resistance are not impaired. The antistatic layer provided as an independent layer is formed by adding an antistatic agent to a vehicle similar to the pattern layer. Antistatic agents include aluminum, gold, silver,
It is a powder or a thin piece of a conductive substance made of a metal such as copper or nickel, a metal oxide such as tin oxide, indium oxide, tin oxide-doped indium oxide (ITO), graphite, or a surfactant. It is also possible to add the antistatic agent to a protective layer, an adhesive layer, a decorative layer, or a release layer. However,
Since it does not reduce the surface properties of the transfer layer, it is preferably not added to the protective layer. When the transfer sheet is transferred, the antistatic layer is
Alternatively, the purpose is to prevent dust from being attracted and attached, or electric shock or spark discharge from occurring when a product having a transfer layer after transfer is used. An antistatic agent may be added to the release layer or the base sheet as long as it only prevents electrostatic charge during transfer. However, it is necessary to add an antistatic agent to any of the transfer layers in order to prevent the transfer target from being charged even after the transfer.

The "normal temperature" here is the natural environment temperature of the earth on which we usually live, and means the state where no special cooling or heating is performed. Particularly, in the present invention, the normal temperature assumed is about 5 to 40 ° C.

As the transfer method, the following methods can particularly fully utilize the characteristics of the transfer sheet of the present invention. Japanese Patent Publication No. 2-4080, Japanese Patent Publication No. 4-19924
Injection molding simultaneous transfer method as disclosed in Japanese Patent Publication No. First, a transfer sheet is inserted between the female mold and the male mold so that the transfer layer faces the male mold side having the ejection holes. If necessary, preform the transfer sheet on the surface of the female mold, then close both molds,
Molten resin is injected from the injection hole into the cavity (molding cavity) between the two molds, the injected resin is cooled and solidified, both molds are opened, and the molded product and the transfer sheet that adheres to it are removed from the mold and separated. Only the moldable base sheet is peeled off and only the transfer layer is left on the molding side. JP-A-4-288214, JP-A-5-5778
Vacuum forming simultaneous transfer method as disclosed in Japanese Patent No. In this, a transfer sheet is placed above the transfer target so that the transfer layer faces the transfer target side. Then, the surface of the transfer target is covered with the transfer sheet by vacuum suction from the transfer target side. If necessary, air pressure is applied from the base sheet side, or pressure is applied with an elastic film such as rubber to assist the molding of the transfer sheet on the transfer target side. When using a heat-sensitive adhesive as the adhesive, before coating the transfer sheet on the surface of the transfer target,
Simultaneously with or after coating, the transfer sheet is heated with a heater to develop the adhesive. Lapping simultaneous transfer method. This is the lapping method,
That is, Japanese Patent Publication No. 59-51900 and Japanese Patent Publication No. 61-58.
As disclosed in Japanese Patent Publication No. 95, Japanese Patent Publication No. 3266/1990, and the like, when a sheet is attached to a columnar body, a pressure roller is used on each side surface of the columnar body to sequentially attach the sheets (for example, In the case of sticking to a square pole, a sheet is sequentially stuck to the upper side surface, the left and right side surfaces, and the lower side, and finally stuck to the four side surfaces. With the adhesive layer side of the transfer sheet facing the transfer target, the transfer sheets are sequentially laminated to each side by lapping, the adhesive layers are adhered by heating, etc., and then only the base sheet is peeled off. . As described above, the transfer sheet of the present invention is effective in transferring a hard coating film by a molding transfer method into a three-dimensional shape in which the transfer sheet is stretched and deformed during transfer. However, the transfer sheet of the present invention may be used in a transfer method such as hot stamping in which the transfer sheet is stretched and is not deformed.

[0028]

In the transfer sheet of the present invention, the protective layer has an average molecular weight of 50,000 to 600,000 and a glass transition temperature of 50 to 13
It is formed from an ionizing radiation curable resin composition in which a non-crosslinked thermoplastic acrylic resin at 0 ° C. and a prepolymer having two or more (meth) acryloyl groups in one molecule are compatible with each other. It is crosslinked and cured by irradiation with ionizing radiation before or after transfer. The acrylic resin is compatible with the prepolymer to form an uncured ionizing radiation-curable resin protective layer in a state where the acrylic resin is applied on a base sheet and the diluting solvent is dried and volatilized. In this compatible state, a portion in which the acrylic resin molecule simple substance is entangled with the prepolymer molecule simple substance, a portion in which the acrylic resin molecule population is entangled with the prepolymer molecule population, and the acrylic resin molecule population is The part where the prepolymer molecule itself has entered,
It is presumed that it is composed of a portion in which the acrylic resin molecule simple substance penetrates into the prepolymer molecule population and a hybrid.

The protective layer at this stage behaves as a solid film having a moderate elastic limit, sufficient plastic deformability (that is, flexibility), and flexibility at room temperature. Further, the protective layer has thermoplasticity. This is because the acrylic resin molecule or molecule group and the prepolymer molecule are close to each other and entwined with each other and fixed by intermolecular force, so that fluidity is suppressed and a non-adhesive solid is obtained. This is because there is no chemical bond in. Therefore, when stress is applied to the protective layer, if the protective layer easily bends and deforms due to elastic deformation while the force within the range that does not exceed the intermolecular force is applied between each molecule, if the stress disappears. Restore the original shape again. Further, when a force exceeding the intermolecular force is applied between the molecules, it is considered that the molecules or the group of molecules are slipped and plastic deformation occurs. Therefore, the protective layer has sufficient flexibility in the uncured state due to external stress.

When the protective layer is further heated to a high temperature, each molecule is gradually released from the constraint of the potential energy of the intermolecular force due to the thermal kinetic energy of the molecules, and the elastic restoring force of the molecules decreases. . Therefore, the plastic deformation becomes stronger, the temperature becomes higher, and when the thermal kinetic energy of the molecule completely overcomes the potential energy of the intermolecular force, the protective layer becomes fluid. Therefore, the protective layer has thermoplasticity.

Due to this flexibility, plastic deformability and thermoplasticity, the uncured protective layer has sufficient moldability.

Further, the ionizing radiation-curable resin composition of the present invention becomes a non-adhesive solid when the solvent is volatilized and dried even in an uncured state after coating. The reason is that the acrylic resin molecules and the prepolymer molecules are entangled and bound with each other by the intermolecular force described above.

The protective layer of the present invention also has greater flexibility, elasticity, and plasticity after crosslinking and curing with ionizing radiation, as compared to the cured layers of prior art ionizing radiation curable resins. . Moreover, it has heat resistance, chemical resistance and abrasion resistance comparable to those of the conventional cured layer of ionizing radiation curable resin. This is because in the protective layer after crosslinking and curing, the non-crosslinking type thermoplastic acrylic resin molecule and the three-dimensional crosslinked structure of the prepolymer molecule are intruded into each other and entangled with each other (so-called interpolymer network), and the prepolymer. It is considered that this is because it is composed of a hybrid of a part consisting only of a three-dimensional crosslinked structure of molecules and a part consisting only of the non-crosslinked thermoplastic acrylic resin molecule population. The mechanical strength of the three-dimensional cross-linked structure of the prepolymer molecules and the deformability, slipperiness, and impact absorption of the acrylic resin molecule group work together to counteract external stress during wear, and It is considered that sufficient abrasion resistance is produced by absorbing and relaxing the part. In addition, the acrylic resin molecule group, the acrylic resin molecule and the three-dimensional crosslinked structure of the prepolymer molecule interpenetrate with each other with respect to external stress at the time of molding, and the entangled structural portions follow the deformation, which is a conventional technique. It is considered that greater moldability can be exhibited as compared with the cured layer of the ionizing radiation curable resin. Further, in the present invention, the pattern layer adjacent to the protective layer also contains the same kind of acrylic resin as that contained in the protective layer, so that the affinity between both layers is increased, and thus the pattern layer and the protective layer are improved. It is possible to improve the adhesiveness, the elongation at the time of transfer, and the strength of the transfer layer after the transfer.

[0034]

[Effect] The transfer sheet of the present invention has the following effects. Compared to a transfer sheet using a thermosetting resin protective layer, the transfer sheet of the present invention is cured by ionizing radiation, so that the protective layer can be cured in a short time within a few seconds. Further, the transfer layer is not deformed by heat. Compared to a transfer sheet in which a liquid monomer and a prepolymer are cured by ionizing radiation, the transfer sheet of the present invention has a coated protective layer, which is a non-adhesive solid even in an uncured state after drying of a diluting solvent. The feature is that it becomes a coating film. Therefore, the transfer sheet of the present invention can be used in a mode in which the protective layer is transferred in the uncured state and has flexibility and thermoplasticity, and then cured by ionizing radiation. Therefore,
The transfer sheet of the present invention is transferred to an object to be transferred having an uneven shape by following the uneven shape without causing cracks or the like, as compared with a transfer sheet in which a liquid monomer and a prepolymer are cured by ionizing radiation. It is possible to
Further, in this case, since the uncured protective layer is a non-adhesive solid coating film, a pattern layer, an adhesive layer and the like can be overprinted on the protective layer by in-line multicolor printing. Further, the transfer sheet can be stored and transported by winding it on a roll whose protective layer is in an uncured state. This was not possible with a transfer sheet using liquid monomers and prepolymers. Since the transfer sheet of the present invention has the composition of the protective layer as defined in the claims, even when the protective layer is cured on the transfer sheet and used in a mode of transferring after that, the liquid monomer and the prepolymer are used. Compared to a transfer sheet that cures a polymer with ionizing radiation, the protective layer has higher flexibility (although the thermoplasticity is lost), and when transferred to a transfer target having an uneven shape, more cracks and damages occur. Is less likely to occur, and the ability to follow uneven shapes is also good. Compared to a transfer sheet in which the protective layer is a solid at room temperature in the uncured state and is composed of a crosslinkable polymer having a radically polymerizable unsaturated group that is thermoplastic, the transfer sheet of the present invention has a protective layer Since the composition is within the range of 1, the scratch resistance, heat resistance, and chemical resistance of the cured protective layer are better. The transfer sheet of the present invention can achieve both heat resistance, chemical resistance and abrasion resistance of the protective layer, which are inherently contradictory, and moldability of the uneven shape, as compared with conventional transfer sheets of various protective layers. Since the specific acrylic resin is contained in both the protective layer and the picture layer, the adhesion between the protective layer and the picture layer is good, and during transfer, even if external stress is applied during molding, peeling between both layers,
Less likely to cause cracks.

[0035]

EXAMPLES Next, examples of the transfer sheet according to the present invention will be specifically described.

Example 1 As a base film, a biaxially stretched polyethylene terephthalate film (T-6 manufactured by Toray)
0 # 25, thickness 25 μm) was coated with 0.3 g / m ² of melamine resin-based ink (manufactured by Zainktec), and 17
By baking at 0 ° C. for 20 seconds to form a release layer, a releasable substrate film was produced. Next, the following ionizing radiation curable resin composition (A) is dissolved and diluted in a mixed solvent of methyl ethyl ketone and toluene, and then applied on the mold release base material fill,
The mixed solvent was volatilized and removed by drying at 60 ° C. for 1 minute to obtain an ionizing radiation curable resin protective layer having a coating amount of 3 g / m ² . Next, the pattern layer composition (X) was diluted with the same mixed solvent as that of (A), and was coated and dried on the ionizing radiation-curable resin protective layer to obtain a pattern layer having a coating amount of 1 g / m ² . Ionizing radiation curable resin composition (A) Non-crosslinking type thermoplastic acrylic resin (Mitsubishi Rayon's Dianal BR-80, average molecular weight 95,000, glass transition temperature 105 ° C) 70 parts by weight Polyester acrylate prepolymer (Made by Toagosei M- 8030, 15 parts by weight Average number of acryloyl groups in one molecule 4) Urethane acrylate prepolymer (UV-7210B, manufactured by Nippon Synthetic, 15 parts by weight Average number of acryloyl groups in one molecule 2.5) Picture layer composition (X) Acrylic resin ( Mitsubishi Rayon's Dianal BR-80) 50 parts by weight Vinyl chloride vinyl acetate copolymer (Vinyl VYHH made by Union Carbide) 50 parts by weight Pigment 5 parts by weight Next, from the picture layer side, an electron beam of 165 keV, 5 Mra
Irradiation was performed under the condition of d to obtain a transfer sheet. Using this transfer sheet, the pattern layer of the transfer sheet is overlaid on the surface of an ABS resin (Styrac ABS 767 manufactured by Asahi Kasei) as the transfer target, and the roll is passed at 200 ° C. and 10 kg / cm ² at 2 m / min. I made it and transferred it.

(Example 2) In Example 1, the ionizing radiation-curable resin composition (A) was replaced with the following ionizing radiation-curable resin composition (B), and the following steps were carried out in the same manner to obtain a transfer sheet. Obtained. Ionizing radiation curable resin composition (B) Non-crosslinking type thermoplastic acrylic resin (Mitsubishi Rayon's Dianal BR-80) 70 parts by weight Polyester acrylate prepolymer (Toa Gosei M-8030) 10 parts by weight Urethane acrylate prepolymer ( Nippon Synthetic UV-7210B) 15 parts by weight Urethane acrylate (Nippon Synthetic UV-3000B) 5 parts by weight

(Example 3) In Example 1, the ionizing radiation-curable resin composition (A) was replaced with the following ionizing radiation-curable resin composition (C), and the following steps were carried out in the same manner to obtain a transfer sheet. Obtained. Ionizing radiation curable resin composition (C) Non-crosslinking type thermoplastic acrylic resin (Mitsubishi Rayon's Dianal BR-80) 65 parts by weight Polyester acrylate prepolymer (Toa Gosei M-8030) 15 parts by weight Urethane acrylate prepolymer ( UV-7210B manufactured by Nippon Gosei Co., Ltd. 15 parts by weight Silica powder (Aerosil # 200 manufactured by Nippon Aerosil) 5 parts by weight

Example 4 As a base film, a biaxially stretched polyethylene terephthalate film (T-6 manufactured by Toray)
0 # 25, thickness 25 μm) was coated with 0.3 g / m ² of melamine resin-based ink (manufactured by Zainktec), and 17
A releasable substrate film was produced by baking at 0 ° C. for 20 seconds to form a release layer. Next, the following ionizing radiation-curable resin composition (D) is dissolved and diluted in a mixed solvent of methyl ethyl ketone and toluene, and then coated on the mold release base material film and dried at 60 ° C. for 1 minute to mix the mixture. The solvent was volatilized and removed to obtain an ionizing radiation curable resin protective layer having a coating amount of 3 g / m ² . Next, the pattern layer composition (Y) was diluted with a mixed solvent and applied on the ionizing radiation-curable resin protective layer and dried to obtain a pattern layer having a coating amount of 2 g / m ² . Ionizing radiation-curable resin composition (D) Non-crosslinking type thermoplastic acrylic resin (Mitsubishi Rayon's Dianal BR-80) 70 parts by weight Polyester acrylate prepolymer (Toa Gosei M-8030) 10 parts by weight Urethane acrylate prepolymer ( Nippon Synthetic UV-7210B) 15 parts by weight Dipentaerythritol Hexaacrylate Monomer (Toa Gosei M-400) 5 parts by weight Picture layer composition (Y) Acrylic resin (Mitsubishi Rayon Dianal BR-80) 35 parts by weight Chloride Vinyl vinyl acetate copolymer (Vinyl VYHH manufactured by Union Carbide) 35 parts by weight Carbon black powder 30 parts by weight Next, from the pattern layer side, an electron beam of 165 keV, 5 Mra
Irradiation was performed under the condition of d to obtain a transfer sheet. Using this transfer sheet, the pattern layer of the transfer sheet is overlaid on the surface of an ABS resin (Styrac ABS 767 manufactured by Asahi Kasei) as the transfer target, and the roll is passed at 200 ° C. and 10 kg / cm ² at 2 m / min. I made it and transferred it.

(Example 5) In Example 1, the ionizing radiation-curable resin composition (A) was replaced with the following ionizing radiation-curable resin composition (E), and the following steps were carried out in the same manner to obtain a transfer sheet. Obtained. Ionizing radiation-curable resin composition (E) Non-crosslinking type thermoplastic acrylic resin (Mitsubishi Rayon's Dianal BR-80) 70 parts by weight Polyester acrylate prepolymer (Toa Gosei M-8030) 10 parts by weight Urethane acrylate prepolymer ( Nippon Synthetic UV-7210B) 15 parts by weight Tripropylene glycol diacrylate monomer (Nippon Kayaku) 5 parts by weight

Example 6 As a base film, a biaxially stretched polyethylene terephthalate film (T-6 manufactured by Toray)
0 # 25, thickness 25 μm), the following ionizing radiation-curable resin composition (F) was coated at a coating amount of solid content of 6 g / m ² to obtain an ionizing radiation-curable protective layer. Ionizing radiation curable resin composition (F) Non-crosslinking type thermoplastic acrylic resin (Mitsubishi Rayon's Dianal BR-80) 15 parts by weight Triazine prepolymer (Mitsubishi Yuka LZ-075) 85 parts by weight Next, acrylic A resin-based pattern layer ink (pattern ink GG manufactured by Showa Ink Kogyo Co., Ltd.) was applied onto the ionizing radiation-curable resin protective layer and dried to obtain a pattern layer having a coating amount of 1 g / m ² . Further, an acrylic resin type adhesive (HS-32 manufactured by Showa Ink Mfg. Co., Ltd.) was applied and dried to give a coating amount of solid content of 1 g / m 2.
^A transfer sheet was obtained by providing the ^second adhesive layer. Using this transfer sheet, the pattern layer of the transfer sheet is overlaid on the surface of an acrylic resin (acrylite manufactured by Mitsubishi Rayon) as a transfer target, and the rolls at 200 ° C. and 10 kg / cm ² are passed at 2 m / min. I made it and transferred it. After that, under the UV irradiation device 160W / cm lamp, 2m / min for 2
Ultraviolet irradiation was performed under the condition of passing once to cure the ionizing radiation curable resin protective layer.

(Example 7) In Example 1, the ionizing radiation-curable resin composition (A) was replaced with the following ionizing radiation-curable resin composition (G), and the following steps were carried out in the same manner to obtain a transfer sheet. Obtained. Ionizing radiation curable resin composition (G) Non-crosslinking type thermoplastic acrylic resin (Mitsubishi Rayon's Dianal BR-80, average molecular weight 430000, glass transition temperature 105 ° C.) 60 parts by weight Polyester acrylate prepolymer (M- manufactured by Toagosei) 8030) 15 parts by weight Urethane acrylate prepolymer (UV-7210B manufactured by Nippon Gosei) 20 parts by weight Silica powder (Aerosil # 200 manufactured by Nippon Aerosil) 5 parts by weight

Comparative Example 1 In Example 1, the ionizing radiation-curable resin protective layer (A) was replaced with the following ionizing radiation-curable resin protective layer (a), and the following steps were carried out in the same manner to obtain a transfer sheet. Obtained. Ionizing radiation curable resin composition (a) Urethane acrylate prepolymer (UV-7210B made by Nippon Gosei) 90 parts by weight 1,6 hexanediol diacrylate monomer (made by Nippon Kayaku) 10 parts by weight

(Comparative Example 2) In Example 1, the ionizing radiation-curable resin protective layer (A) was replaced with the following ionizing radiation-curable resin protective layer (b), and the following steps were carried out in the same manner to obtain a transfer sheet. Obtained. Ionizing radiation curable resin composition (b) Non-crosslinking type thermoplastic acrylic resin (Mitsubishi Rayon's Dianal BR-80) 90 parts by weight 1,6 hexanediol diacrylate monomer (manufactured by Nippon Kayaku) 10 parts by weight

(Comparative Example 3) In Example 1, the ionizing radiation-curable resin protective layer (A) was replaced with the following ionizing radiation-curable resin protective layer (c), and the following steps were carried out in the same manner to obtain a transfer sheet. Obtained. Ionizing radiation curable resin composition (c) Non-crosslinked thermoplastic acrylic resin (Mitsubishi Rayon's Dianal BR-87, average molecular weight 25000, glass transition temperature 105 ° C.) 60 parts by weight Polyester acrylate prepolymer (Made by Toagosei M- 8030) 15 parts by weight Urethane acrylate prepolymer (UV-7210B manufactured by Nippon Gosei) 20 parts by weight Silica powder (Aerosil # 200 manufactured by Nippon Aerosil) 5 parts by weight

(Measurement / Evaluation Method) The measurement / evaluation method will be described below.

(Drying property to the touch) The coated surface and the polyethylene terephthalate film surface were superposed, and the load was 100 g.
It was judged whether or not there is a change in appearance on the coated surface after leaving for 1 minute at / cm2.

(Adhesion of Transfer Layer) The surface transferred to the transferred material was subjected to an adhesion test with a cellophane tape to determine whether or not peeling occurred between the transferred material and the transfer layer.

(Steel wool property) The surface transferred to the transferred material is reciprocated 10 times using steel wool # 0000.
It was lightly rubbed with a hand and it was judged whether or not there was a change in appearance such as scratches on the surface.

(Pencil hardness) The measurement was performed according to JIS K5400.

(Elongation) A polyester film (HP-7 manufactured by Teijin, thickness 188 μm) provided with a protective layer was prepared by using a tensile strength tester Tensilon.
Tensile rate of 10% and 30% at a speed of 200 mm / min
In this case, it was judged whether or not there would be a visual change such as cracks in the protective layer.

[0052]

[Table 1]

Claims (1)

[Claims] 1. A transfer sheet having at least an ionizing radiation curable resin protective layer and a pattern layer as a transfer layer on a releasable substrate sheet in this order, wherein the ionizing radiation curable resin protective layer has an average molecular weight. 5000
0 to 600,000, a glass transition temperature of 50 to 130 ° C., a non-crosslinking type thermoplastic acrylic resin, and a prepolymer having two or more acryloyl groups or methacryloyl groups in one molecule, and the pattern layer has an average molecular weight of 50,000. ~ 600,000,
A transfer sheet comprising a non-crosslinked thermoplastic acrylic resin having a glass transition temperature of 50 to 130 ° C.