JP2019104120A - Set of thermal transfer image-receiving sheet and thermal fusion type ink ribbon - Google Patents

Abstract

To provide a set of a thermal transfer image-receiving sheet and a thermal fusion type ink ribbon which has followability to a curved surface capable of being stuck to a curved surface shape, scratch resistance of an image-receiving layer, excellent printed performance by a thermal fusion type ink ribbon of the image-receiving layer, and excellent scratch resistance of a printed image.SOLUTION: There is provided a set of a thermal transfer image-receiving sheet in which an image-receiving layer is laminated on a thermoplastic urethane elastomer base material and a thermal fusion type ink ribbon that thermally transfers an ink to the image-receiving layer, in which the image-receiving layer is a layer formed by curing a composition containing urethane acrylate as a main agent and acrylate having a polybutadiene skeleton, a thickness of the image-receiving layer is 0.8 μm or more and 2.0 μm or less, and a transfer layer being the uppermost layer of the thermal fusion type ink ribbon in contact with the image-receiving layer in thermal transfer contains a resin selected from the group consisting of an epoxy resin, an ethylene-vinyl acetate copolymer resin and a modified polypropylene resin.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a thermal transfer image receiving sheet for printing (printing) with a thermal melting transfer recording medium, and more specifically, a thermal transfer image receiving sheet capable of adhering to the surface of a curved adherend. And a set of heat melting ink ribbons used for the same.

Conventionally, a thermal transfer image receiving sheet has been proposed in which a printed image printed with a heat melting transfer recording medium (hereinafter referred to as a heat melting ink ribbon) can obtain excellent scratch resistance, as disclosed in Patent Document 1 etc. ing. Patent Document 2 and the like propose a thermal transfer image-receiving sheet that can be attached to follow the surface of a curved adherend. Further, Patent Document 3 and the like propose a thermal transfer image-receiving sheet having an excellent scratch resistance in which an image-receiving layer printed with a heat-meltable ink ribbon is excellent.

  In the thermal transfer image receiving sheet of Patent Document 2, by using a flexible urethane elastomer as a substrate of the thermal transfer image receiving sheet, the entire thermal transfer image receiving sheet is flexible, and the thermal transfer image receiving sheet has a curved surface of the adherend surface You can follow and paste it. (Hereafter, this performance is called curved surface followability.)

On the other hand, in Patent Document 3, the ink receiving layer (image receiving layer) is made of a hard material such as an active energy ray curable resin, so that the image receiving layer printed with the heat melting ink ribbon of the thermal transfer image receiving sheet is excellent. It provides scratch resistance.

  Thus, while it is necessary to use a flexible substrate in order to impart curved surface followability to the thermal transfer image receiving sheet, in order to impart scratch resistance to the image receiving layer of the thermal transfer image receiving sheet. It is necessary to harden the image receiving layer, and it has been difficult to simultaneously improve curved surface followability and scratch resistance. Further, the image receiving layer of the thermal transfer image receiving sheet needs to have excellent printing performance which is the most important performance of the thermal transfer image receiving sheet, in addition to the excellent scratch resistance of the printed image as described in Patent Document 1. It is even more difficult to obtain a thermal transfer image-receiving sheet having good performance in all of these performances, and conventionally, no thermal transfer image-receiving sheet has good performance in all of these performances.

Japanese Patent Application Publication No. 06-000899 JP, 2017-170896, A Japanese Patent Application Laid-Open No. 10-264335

The present invention has been made in view of the above circumstances, and it can follow and adhere to the surface of a curved adherend, excellent scratch resistance of the image receiving layer, and heat melting ink of the image receiving layer It is an object of the present invention to provide a set of a thermal transfer image receiving sheet and a thermal melting ink ribbon, which combine the excellent printing performance by the ribbon and the excellent abrasion resistance of the printed image printed by the thermal melting ink ribbon. is there.

  A first invention is a set of a thermal transfer image receiving sheet in which an image receiving layer is laminated on one surface of a thermoplastic urethane elastomer substrate and a heat melting ink ribbon for thermally transferring the ink to the image receiving layer, wherein the image receiving layer is It is a layer formed by curing a composition in which a part of the urethane acrylate is a urethane acrylate having a polybutadiene skeleton with a urethane acrylate as a main agent, and the thickness of the image receiving layer is 0.8 μm to 2.0 μm. The transfer layer which is the uppermost layer of the heat melting ink ribbon contacting the image receiving layer at the time of thermal transfer contains a resin selected from the group consisting of an epoxy resin, an ethylene-vinyl acetate copolymer resin, and a modified polypropylene resin. It is a set of a thermal transfer image-receiving sheet and a thermal melting type ink ribbon which are characterized by the present invention.

A second invention is a resin selected from the group consisting of an epoxy resin, an ethylene-vinyl acetate copolymer resin, and a modified polypropylene resin, which is the uppermost layer of the heat melting ink ribbon contacting the image receiving layer at the time of the thermal transfer. And 35% by weight or more of the solid content of the thermal transfer image-receiving sheet and the heat-meltable ink ribbon according to the first invention.

The third invention is characterized in that an adhesive layer or an adsorption layer is laminated on the surface opposite to the surface on which the image receiving layer of the thermoplastic urethane elastomer base material is laminated. It is a set of a thermal transfer image receiving sheet and a thermal melting type ink ribbon.

The fourth aspect of the present invention is mainly characterized in that the adsorption layer is formed by curing a silicone composition comprising a diorganopolysiloxane having two or more alkenyl groups in one molecule and an organohydrogenpolysiloxane by an addition reaction. It is a set of the thermal transfer image-receiving sheet according to the third invention and the thermal melting type ink ribbon as described in the third invention.

In the fifth invention, the diorganopolysiloxane is a linear diorganopolysiloxane having a vinyl group only at both ends, a linear diorganopolysiloxane having a vinyl group at both ends and a side chain, a vinyl only at the end The thermal transfer image-receiving sheet and the thermal melting ink ribbon according to the fourth aspect of the present invention, wherein the thermal transfer image-receiving sheet is at least one selected from branched diorganopolysiloxanes having at least one group and branched diorganopolysiloxanes having terminal and vinyl groups at side chains. It is a set.

  A sixth invention is a set of the thermal transfer image receiving sheet and the heat melting ink ribbon according to any one of the first to fifth inventions, wherein the thickness of the thermoplastic urethane elastomer substrate is 50 μm to 150 μm.

The thermal transfer image receiving sheet of the present invention has a thermoplastic urethane elastomer as a base material and on one surface thereof, an image receiving layer having a thickness of 0.8 μm or more and 2.0 μm or less containing urethane acrylate as a main agent. Thus, it was possible to have curved surface followability capable of adhering to follow the surface of a curved adherend and excellent scratch resistance of the image receiving layer. Further, since the thermal transfer image receiving sheet of the present invention contains urethane acrylate having a polybutadiene skeleton in urethane acrylate of the image receiving layer, the transfer layer which is the uppermost layer in contact with the image receiving layer at the time of thermal transfer is epoxy resin, ethylene-vinyl acetate By combining with a heat melting ink ribbon containing a resin selected from the group consisting of a copolymer resin and a modified polypropylene resin, excellent printing performance by the heat melting ink ribbon, and printing with a heat melting ink ribbon It was possible to have excellent scratch resistance of the printed image.

The thermal transfer image receiving sheet and the thermal melting ink ribbon of the present invention will be described in more detail below.

(Thermal transfer image receiving sheet)
A schematic view of the layer structure of the thermal transfer image receiving sheet X and the thermal melting ink ribbon Y according to the first embodiment of the present invention is shown in FIG. The thermal transfer image-receiving sheet X has three layers of the anchor layer 2A, the silicone adsorption layer 2 and the separator A1 on one side of the thermoplastic urethane elastomer base material 3 (hereinafter referred to as TPU base material 3) on the TPU base material 3 side. The anchor layer 4A and the image receiving layer 4 are laminated in this order from the TPU base material 3 side on the other side of the TPU base material 3.

(Thermoplastic urethane elastomer base material: TPU base material 3)
The TPU base material 3 in the present invention is prepared by adding the thermoplastic urethane elastomer and other components into an extruder, a kneader, a Banbury mixer or the like and melt-kneading it by a conventionally known method, to prepare a kneaded product (master batch) By passing the kneaded material through a calender, a T-die or the like, it is possible to use a sheet-like or plate-like shape.

In the thermal transfer image-receiving sheet X, the TPU substrate 3 is preferably formed on a temporary support such as a PET film, or a commercially available TPU substrate provided on the temporary support is preferably used. This is because the TPU base material 3 alone has a small tensile strength, and when laminating another layer on the TPU base material 3, the TPU base material 3 may stretch or break. For this reason, it is preferable to laminate the anchor layer 4A on the TPU base material 3 in the state of being laminated on the temporary support. The thickness of the TPU substrate 3 is preferably 50 μm or more and 150 μm or less, and more preferably 70 μm or more and 100 μm or less. When the thickness of the TPU substrate is less than 50 μm, it tends to be wrinkled at the time of sticking, making it difficult to handle. On the other hand, when the thickness of the TPU base material 3 is larger than 150 μm, the curved surface followability may be lowered, and it is also economically wasteful.

As a temporary support on which the TPU substrate 3 is laminated, a film having a single layer or multilayer structure made of polyethylene terephthalate, polyethylene, polystyrene, polypropylene, nylon, urethane, polyvinylidene chloride, polyvinyl chloride or the like can be used. The thickness of the temporary support is usually 10 to 300 μm, preferably 25 to 200 μm.

As a method of coating or laminating a kneaded product (master batch) obtained by melting a thermoplastic urethane elastomer on a temporary support, a multistage roll coater represented by a three offset gravure coater or a five roll coater, a direct gravure coater, Well-known methods, such as a bar coater, an air knife coater, and a T-die, are suitably used.

(Thermoplastic urethane elastomer)
As thermoplastic urethane elastomer (TPU) which is a material of TPU substrate 3, although what was constituted from the following hard segment and a soft segment is mentioned, in order to adjust curved surface flattery nature of thermal transfer image receiving sheet X, isocyanate The tensile strength and the elongation at break of the TPU substrate 3 can be adjusted to appropriate values by appropriately adjusting the compounding amount of the polyol component.

Examples of the hard segment include those composed of diisocyanate and 1,9 nonanediol, alkanediol such as 1,4-butanediol and diethylene glycol, or dialkylene glycol such as polytetramethylene ether glycol.

Examples of the soft segment include diisocyanates or adducts obtained by blending an alkanediol such as 1,3 butanediol with diisocyanate, or polyoxypropylene, polyoxyethylene, polyoxypropylene-polyoxyethylene, polyoxybutylene, polyoxybutylene-poly Polyethers such as oxyethylene, polytetramethylene, or polyoxybutylene-polyoxyethylene-glycol, or polyesters such as alkanediol-polyadipate, and polycarbonate diols can be mentioned. Here, as the diisocyanate, 4,4'-diphenylmethane-diisocyanate, 1,6-hexamethylene-diisocyanate, isophorone diisocyanate and the like can be mentioned.

  The TPU base material 3 of the thermal transfer image receiving sheet X includes other components in addition to the thermoplastic urethane elastomer component within a range that does not impair the flexibility for satisfying the property capable of being attached to the curved surface of the thermal transfer image receiving sheet X be able to. Examples of other components include modifiers (processing aids), plasticizers, heat stabilizers, antioxidants, light stabilizers, UV absorbers, flame retardant aids, antiblocking agents, etc. These can be used alone or in combination of two or more as needed.

(Adsorption layer or adhesive layer)
The thermal transfer image-receiving sheet X of the present invention is any sheet for adhering to an adherend such as a screen on the opposite side of the image-receiving layer 4 to which the ink is transferred from the heat-melting ink ribbon Y of the TPU substrate 3 It is preferable to provide an adsorption layer or an adhesive layer. As a useful application of the thermal transfer image-receiving sheet X of the present invention, it can be considered to be used for advertising, decoration, etc. by sticking it on a glass surface in a storefront, a smooth surface of a product sample or the like. In consideration of use for such applications, it is preferable that the thermal transfer image-receiving sheet X of the present invention can be re-sticked when it is stuck at the wrong position, or can be easily peeled off when it becomes unnecessary It is preferable to provide an adsorption layer from this point. In addition, in view of aesthetics, the thermal transfer image-receiving sheet X of the present invention preferably has high transparency, considering that it is used for such applications. Therefore, various adsorbents may be used for the adsorption layer of the present invention. Among the adsorbents, silicone adsorbents are preferred. Hereinafter, as a description of the pressure-sensitive adhesive layer or the adsorption layer of the thermal transfer image receiving sheet X of the present invention, the silicone adsorption layer 2 will be described as an example.

(Anchor layer 2A)
In order to laminate the silicone adsorption layer 2 on the TPU substrate 3, it is preferable to provide an anchor layer 2A between the TPU substrate 3 and the silicone adsorption layer 2. The purpose of providing the anchor layer 2A is to improve the adhesion between the TPU substrate 3 and the silicone adsorption layer 2, and to increase the adhesion with time due to the reaction between the glass surface and the silicone oligomer, particularly when the adherend is glass. When the thermal transfer image-receiving sheet X is peeled off, it can be peeled off smoothly without generating a silicone residue on the glass surface which is the adherend.

As resin used for anchor layer 2A, it is preferred to use polyester system resin which has an acid value of 7-100 mgKOH / g.

When the acid value of the polyester resin is less than 7 mg KOH / g, the adhesion between the anchor layer 2A and the silicone adsorption layer 2 and between the anchor layer 2A and the TPU base material 3 is weak. It becomes easy to leave from 3. In addition, when the protective film X is peeled off after the thermal transfer image-receiving sheet X is attached to the adherend, the silicone residue is easily generated on the adherend. When the acid value exceeds 100 mg KOH / g, the water resistance of the resin film is insufficient.

The anchor layer 2A coating liquid can be prepared by a conventionally known method.

 The thickness of the anchor layer 2A is preferably 0.1 to 5 μm, and more preferably 0.15 to 3 μm. When the thickness of the anchor layer 2A is less than 0.1 μm, the thermally crosslinked silicone adsorption layer 2 is easily separated from the anchor layer 2A, and the anchor layer 2A is also easily separated from the TPU substrate 3. On the other hand, it is useless that the thickness of the anchor layer 2A exceeds 5 μm, and the flexibility of the entire thermal transfer image receiving sheet X is lost, and the curved surface followability to the adherend decreases.

In the coating solution for the anchor layer 2A of the thermal transfer image-receiving sheet X, in addition to the resin components described above, in order to improve the wettability to the TPU base material 3, water is used in the range not inhibiting the dispersibility of the coating solution. Organic solvents such as miscible alcohols may be added. In addition, as another method, a wettability improver can be added in the range which does not become a catalyst poison to the crosslinking reaction of the addition reaction type silicone resin. Further, if necessary, those generally added to this type of composition such as a vulcanizing agent, a vulcanization accelerator, etc. can be added in the range where the effect of the present invention is not reduced.

(Silicone adsorption layer 2)
The properties of silicone used in the silicone adsorption layer 2 of the thermal transfer image-receiving sheet X are required to be high in transparency and to have flexibility like rubber. The performance of the silicone adsorption layer 2 is required to be such that the surface follows the surface of the adherend and can be easily peeled off from the surface of the adherend with a small peeling force at the time of peeling from the adherend. In addition, as processing performance of silicone used for the silicone adsorption layer 2, it is possible to provide a crosslinked silicone adsorption layer 2 only by coating and heat treatment without using a method of coating thickness with a film thickness of at least 10 μm or more. Is required. As such silicones, addition type liquid silicone resins which are cross-linked in a short time at a low temperature of 150 ° C. or less in curing reaction and which are transparent, heat resistant, excellent in compression set characteristics and low in viscosity and liquid type Use is preferred. The addition type liquid silicone resin is a hydroxyl catalyst of a diorganopolysiloxane having an alkenyl group such as two or more vinyl groups in one molecule and an organohydrogenpolysiloxane having a SiH group as a crosslinking agent under a platinum catalyst or the like. It can be thermally crosslinked by reaction.

As such a diorganopolysiloxane, a linear diorganopolysiloxane having a vinyl group at both ends, a linear diorganopolysiloxane having a vinyl group at both ends and a side chain, a vinyl group at only the end It is preferable to use at least one or more selected from branched diorganopolysiloxanes having one or more terminal groups and branched diorganopolysiloxanes having a vinyl group at the terminal and side chains.

A linear diorganopolysiloxane having a vinyl group only at both ends, which is one form of these diorganopolysiloxanes, is represented by the following general formula (Formula 1).

(Wherein R represents the following organic group, n represents an integer)

(Wherein R represents the following organic group, and m and n represent integers)

The organic group (R) bonded to a silicon atom other than the vinyl group may be different or the same, but specific examples thereof include an alkyl group such as methyl group, ethyl group and propyl group, and an aryl group such as phenyl group and tolyl group Or a monovalent hydrocarbon group other than the same or different unsubstituted or substituted aliphatic unsaturated group in which part or all of hydrogen atoms bonded to carbon atoms of these groups are substituted with halogen atoms, cyano groups and the like Preferably, at least 50 mol% of them are methyl groups, etc., but this diorganopolysiloxane may be used alone or as a mixture of two or more.

The linear diorganopolysiloxane having a vinyl group at both ends and a side chain is a diorganopolysiloxane in which a part of R in the general formula (Formula 1) is a vinyl group. The branched diorganopolysiloxane having a vinyl group only at the end is a diorganopolysiloxane represented by the above general formula (Formula 2). The branched diorganopolysiloxane having a vinyl group at the terminal and side chain is a diorganopolysiloxane in which a part of R in the general formula (Formula 2) is a vinyl group.

(MQ resin)
In addition to the above components, the silicone composition constituting the silicone adsorption layer 2 of the present invention further comprises M units (R ₃ SiO _1/2 : R is a monovalent organic group such as a methyl group or a phenyl group) and Q You may contain the MQ resin which consists of a unit (SiO4 _{* 1/2} ). The MQ resin may be either non-reactive or reactive, and may contain both non-reactive and reactive.

The crosslinking agent used for the crosslinking reaction of the composition which comprises the silicone adsorption layer 2 here may be a well-known thing. Examples of crosslinking agents include organohydrogenpolysiloxanes. Organohydrogenpolysiloxanes have at least 3 hydrogen atoms bonded to silicon atoms in one molecule, but from a practical point of view, 50% by weight of those having two ≡SiH bonds in the molecule The remainder may include at least three 少 な く と も SiH bonds in the molecule.

The platinum-based catalyst used for the crosslinking reaction may be a known one, and examples thereof include chloroplatinic acid such as chloroplatinic acid and chloroplatinic acid, alcohol compounds of chloroplatinic acid, aldehyde compounds or chloroplatinic acid and various olefins Chain salt with and the like. The cross-linked silicone layer becomes flexible like silicone rubber, and this softness makes it easy to adhere to the adherend.

  Commercially available forms of silicone according to the present invention include solvent-free, solvent-type, and emulsion-type, but any type can be used. Among them, the non-solvent type is very advantageous in terms of safety, hygiene and air pollution since it does not use a solvent. However, even if it is a non-solvent type, an organic solvent such as toluene can be added as needed to adjust the viscosity to obtain a desired film thickness.

  As described above, as the properties of the silicone adsorption layer, it is required to have flexibility like rubber and to secure the adhesion following the irregularities of the surface of the adherend at the time of adhesion to the adherend. . The film thickness of the silicone adsorption layer is required to be at least 10 μm or more, usually 15 to 50 μm, in order to secure the shear force in the adhesion surface direction of the silicone adsorption layer to the adherend. If the thickness is less than 10 μm, the adhesion of the thermal transfer image receiving sheet X to the adherend can not be secured, and the thermal transfer image receiving sheet X is likely to peel off from the adherend particularly when attached for a long period of time.

As a coating method of the anchor layer 2A coating liquid and the silicone adsorption layer 2 coating liquid, a multistage roll coater represented by a three offset gravure coater or a five roll coater, a direct gravure coater, a bar coater, an air knife coater, etc. The method of is suitably used.

(Separator A1)
The separator A1 is a resin film separator for preventing the contamination of the surface of the silicone adsorption layer 2 and the adhesion of foreign substances, and for improving the handling of the thermal transfer image receiving sheet X. The separator A1 is used by being bonded to the surface of the silicone adsorption layer 2. The separator A1 is made of a highly releasable resin film made of polyethylene terephthalate, polyethylene, polypropylene or the like, and, if desired, one coated with a release agent such as a silicone material on the surface is used.

(Anchor layer 4A)
In the thermal transfer image receiving sheet X according to the present invention, the image receiving layer 4 is provided on the surface opposite to the TPU substrate 3 on which the silicone adsorption layer 2 is provided. Since the TPU substrate 3 is soft, the surface of the thermal transfer image-receiving sheet X is easily damaged if the thermal transfer image-receiving sheet X is used in a state where the TPU substrate 3 is exposed. Therefore, the image receiving layer 4 is preferably a hard coat layer. The image receiving layer 4 is preferably provided with an anchor layer 4A on the TPU base material 3 and laminated on the anchor layer 4A. The purpose of providing the anchor layer 4A is to uniformly coat the thin image-receiving layer 4 to prevent the occurrence of curling during curing and to improve the adhesion between the image-receiving layer 4 and the TPU substrate 3.

The anchor layer 4A preferably contains a polyol as a main component, and although polyether polyol, polyester polyol, acrylic polyol, polycarbonate polyol, epoxy polyol and the like can be used, the solvent-based hard coat layer is coated on the anchor layer 4A. From the viewpoint of preventing whitening of the TPU base material 3 when the liquid is applied, polyester polyols are more preferable.

  In the present invention, it is preferable that the anchor layer 4A is compounded with 0.1 to 100 parts by weight of a carbodiimide compound as a crosslinking agent with respect to 100 parts by weight of the polyester polyol. When the blending amount of the carbodiimide compound is less than 0.1 parts by weight, the coating liquid of the anchor layer 4A is not sufficiently crosslinked. When the content of the carbodiimide compound exceeds 100 parts by weight, the image receiving layer 4A is whitened. In the thermal transfer image receiving sheet X, by using such an anchor layer 4A, it is possible to ensure good adhesion of the image receiving layer 4 to the TPU base material 3.

  The polyester polyol which is the main component of the anchor layer 4A is one obtained by condensation polymerization of polyvalent carboxylic acid and polyvalent alcohol. Examples of polyvalent carboxylic acids include aliphatic polyvalent carboxylic acids such as malonic acid, glutaric acid, adipic acid, pimelic acid, azelaic acid, sebacic acid and dodecanedicarboxylic acid, and unsaturated polyvalent carboxylic acids such as fumaric acid and maleic anhydride Acids, phthalic acid, dimethyl phthalic acid, phthalic anhydride, isophthalic acid, terephthalic acid, dimethyl terephthalic acid, aromatic polyvalent carboxylic acids such as 5-sodium sulfoisophthalic acid, and the like can be mentioned.

  Examples of polyhydric alcohols include aliphatic glycols, alicyclic glycols, aromatic glycols and aliphatic triols. Although various well-known polyester polyols by these combination can be used, the thing of the range of 1000-40000 as a number average molecular weight is preferable, and a thing of 1-30 mgKOH / g can be used as a hydroxyl value. If the number average molecular weight is less than 1000, the adhesion is insufficient, and if it exceeds 40000, the processability, the appearance of the coating film, and the solubility may be poor.

  As the carbodiimide compound, any one can be used, and among them, bis (2,6-diisopropylphenyl) carbodiimide and 2,6,2 ', 6'-tetraisopropyldiphenylcarbodiimide are preferable from the viewpoint of reactivity and stability. preferable. Furthermore, as said carbodiimide compound, a commercially available carbodiimide compound can be suitably used, without needing to synthesize | combine. As such commercially available carbodiimide compounds, for example, those of various grades sold by Nisshinbo Chemical Co., Ltd. under the trade name of "carbodiimide" (registered trademark) can be used.

  The carbodiimide compound is one having a carbodiimide equivalent (molecular weight / number of carbodiimide groups contained in the molecule) of 100 to 1,000.

The thickness of the anchor layer 4A is preferably 0.2 μm or more and 5 μm or less, more preferably 0.3 μm or more and 2 μm or less. If the thickness of the anchor layer 4A is less than 0.2 μm, the adhesion between the image receiving layer 4 and the TPU substrate 3 may be insufficient. On the other hand, if it exceeds 5 μm, it is economically wasteful.

(Image receiving layer 4)
In order to satisfy the excellent scratch resistance of the image receiving layer which is one of the problems of the present invention, the image receiving layer 4 is preferably a hard layer. On the other hand, in order to ensure the curved surface followability of the thermal transfer image receiving sheet X onto the adherend, which is one of the other problems of the present invention, the image receiving layer 4 must have flexibility to follow the curved surface. You must. In order to satisfy such contradictory properties required for the image receiving layer 4, the image receiving layer 4 is preferably a thin hard coat layer. By using a hard coat layer, the surface of the image receiving layer 4 can be hardened, and by thinning, the entire image receiving layer 4 can be made flexible. However, if the thickness is reduced, the scratch resistance of the hard coat layer tends to decrease, and if it is a hard but brittle hard coat layer, the image receiving layer 4 (hard coat layer) can be formed by making the image receiving layer 4 follow a curved surface. Cracking and floating are likely to occur. Since the image receiving layer 4 of the present invention is required to have a curved surface followability, it has sufficient scratch resistance even if it is thin, and it is a property that cracking and floating hardly occur even if the thermal transfer image receiving sheet X is stretched to follow the curved surface. The hard coat layer which has is preferable. As such a hard coat layer, a hard coat layer obtained by applying a hard coat layer coating liquid containing a urethane acrylate as a main component and then heat or photo curing it can be mentioned. Moreover, it is preferable that the coating liquid for producing the hard-coat layer which has a urethane acrylate as a main component is a coating liquid of a solvent type. It is difficult to make the viscosity of the non-solvent type coating liquid low and it is easy to generate coating unevenness, so it is not suitable for coating a thin hard coat layer as in the present invention, and coating unevenness occurs. By being easy to do, curling at the time of curing is also easily generated.

The urethane acrylate used in the present invention is produced by a known method using a polyol, diisocyanate or hydroxy (meth) acrylate in combination with one or more kinds.

Examples of the polyol include spiro glycol, ethoxylated bisphenol A, ethoxylated bisphenol S, polytetramethylene oxide diol, polytetramethylene oxide triol, polypropylene oxide diol, polypropylene oxide triol and the like.

Examples of the diisocyanate include tetramethylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, 2,4-tolylene diisocyanate, 4,4′-diphenyl diisocyanate, 1,5-naphthalene diisocyanate, 3,3′-dimethyl-4, 4-diphenyl diisocyanate, xylene diisocyanate, trimethylhexamethylene diisocyanate, 4, 4-diphenylmethane diisocyanate, tolylene diisocyanate, etc. may be mentioned.

As the above-mentioned hydroxy (meth) acrylate, for example, 2, 2-bis [4- (3-acryloxy 2-hydroxypropoxy) phenyl] propane, bis [4- (3-acryloxy 2- hydroxypropoxy) phenyl] methane , Bis [4- (3-acryloxy-2-hydroxypropoxy) phenyl] sulfone, bis [4- (3-acryloxy-2-hydroxypropoxy) phenyl] ether, 4,4-bis [4- (3-acryloxy-) 2-hydroxypropoxy) phenyl] cyclohexane, 9,9-bis [4- (3-acryloxy-2-hydroxypropoxy) phenyl] fluorene, 9,9-bis [4- (3-acryloxy-2-hydroxypropoxy) phenyl ] Anthraquinone, 2-hydroxyethyl (meth) acrylate 2-hydroxypropyl acrylate, glycidol dimethacrylate, pentaerythritol triacrylate, and the like.

The image receiving layer is a hard coat by combining the specific image receiving layer of the thermal transfer image receiving sheet with the specific uppermost layer (transfer layer) of the heat melting ink ribbon contacting with the image receiving layer at the time of thermal transfer. It has been found that, even in the case of a layer, excellent printing performance can be ensured by the heat-meltable ink ribbon of the image receiving layer. The specific image receiving layer is an image receiving layer in which a part of urethane acrylate which is a main component of the image receiving layer is urethane acrylate having a polybutadiene skeleton. In addition, the uppermost layer (transfer layer) of the specific heat melting ink ribbon is a layer containing a resin selected from the group consisting of an epoxy resin, an ethylene-vinyl acetate copolymer resin, and a modified polypropylene resin. The excellent printing performance by the heat-meltable ink ribbon of the image-receiving layer obtained by combining the specific image-receiving layer of this thermal transfer image-receiving sheet and the specific uppermost layer (transfer layer) of this heat-meltable ink ribbon is Not only can you get printouts. By combining the image receiving layer and the uppermost layer (transfer layer), the printed image printed on the image receiving layer has excellent abrasion resistance, and the printing is performed even if the thermal transfer image receiving sheet is stretched by applying a tensile load. The image is less likely to be lifted or cracked. As described above, the inventors of the present invention have been able to obtain excellent curved surface followability even for a printed image printed on the image receiving layer by combining the heat melting ink ribbon of the present invention and the thermal transfer image receiving sheet. I found it.

Therefore, the image receiving layer 4 of the thermal transfer image receiving sheet X of the present invention is a hard coat layer obtained by curing a composition which is mainly composed of urethane acrylate and a part thereof is urethane acrylate having a polybutadiene skeleton.

In the image receiving layer 4 of the present invention, by containing a urethane acrylate having a polybutadiene skeleton, the printability of the image receiving layer by a specific heat melting ink ribbon can be improved without containing particles, The high transferability of the thermal transfer image-receiving sheet X can be compatible, and the haze value of the thermal transfer image-receiving sheet X is usually 2% or less and does not exceed 3% at most unless containing a material that impairs the transparency. .

Since the urethane acrylate having a polybutadiene skeleton is the same as the main component used in the image receiving layer (urethane acrylate), the bond by the polymerization reaction in the image receiving layer can be strengthened and the effect of the hard coat can be further enhanced. The effect of being able to

The content of the urethane acrylate having a polybutadiene skeleton contained in the image receiving layer 4 is preferably 0.1 to 8% by weight, more preferably 0.2 to 8% by weight, still more preferably 0.2 based on the image receiving layer. It is 1% by weight. If the amount is less than 0.1% by weight, the printability improvement effect of the image receiving layer 4 by the heat melting ink ribbon can not be sufficiently obtained, and if it exceeds 8% by weight, not only the hardness sufficient for the image receiving layer can not be obtained Is not preferred.

The image receiving layer 4 preferably contains at least one selected from N-vinylformamide, (meth) acryloyl morpholine and phenoxy group-containing (meth) acrylate. As the phenoxy group-containing (meth) acrylate, 2-phenoxy-2-hydroxypropyl (meth) acrylate, 2-hydroxy-3-phenoxypropyl (meth) acrylate, 2-phenoxy-ethyl (meth) acrylate, 3-phenoxypropyl Examples include (meth) acrylates and the like. These may be used alone or in combination of two or more. A compound having a (meth) acryloyl group which is a compound of the main component used in an image receiving layer by containing at least one selected from N-vinylformamide, (meth) acryloyl morpholine and phenoxy group-containing (meth) acrylate The compatibility with the urethane acrylate having a polybutadiene skeleton is extremely good, and it is possible to achieve both high transparency and hardness.

The total amount of at least one selected from N-vinylformamide, (meth) acryloyl morpholine, and phenoxy group-containing (meth) acrylate is preferably 5 to 25% by weight based on the hard coat layer, More preferably, it is 10 to 20% by weight. If it is less than 5% by weight, high transparency can not be obtained because the compatibility between the compound having a (meth) acryloyl group and the urethane acrylate having a polybutadiene skeleton is poor, and if it exceeds 25% by weight, sufficient hardness for the image receiving layer 4 May not be obtained, which is not preferable.

Examples of the photopolymerization initiator used for the ionizing radiation polymerization reaction of the urethane acrylate used in the present invention include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-butyl ether, benzoin isobutyl ether, acetophenone, Dimethylaminoacetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-Methyl-1- [4- (methylthio) phenyl] -2-morpholino-propan-1-one, 4- (2-hydroxyethoxy) phenyl-2 (hydroxy-2-propyl) ketone, benzof Enone, p-phenylbenzophenone, 4,4'-diethylaminobenzophenone, dichlorobenzophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 2-aminoanthraquinone, 2-methylthioxanthone, 2-ethylthioxanthone, 2-chlorothioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, benzyl dimethyl ketal, acetophenone dimethyl ketal, p-dimethylamine benzoate, and the like. These may be used alone or in combination of two or more, and the amount thereof is usually selected in the range of 0.2 to 15 parts by weight with respect to 100 parts by weight of urethane acrylate.

The image receiving layer 4 may be a thermoplastic polymer, an antifoaming agent, a coatability improving agent, a thickener, a surfactant, an organic compound, as long as the scratch resistance and the printability of the image receiving layer 4 by the heat melting ink ribbon are not significantly impaired. It may contain a system lubricant, an antioxidant, an ultraviolet light absorber, a foaming agent, a dye, a pigment, an antistatic agent and the like. The thickness of the image receiving layer 4 is preferably 0.8 μm or more and 2.0 μm or less. When the thickness of the image receiving layer 4 is less than 0.8 μm, the scratch resistance of the surface of the image receiving layer 4 is reduced. In addition, when the thickness of the image receiving layer 4 exceeds 2.0 μm, the curved surface followability at the time of affixing the thermal transfer image receiving sheet X to the adherend is deteriorated, and the scratch resistance is improved even if it exceeds 2.0 μm. Because it is not, it is useless.

When the thermal transfer image-receiving sheet X is attached to an adherend, the separator A1 is peeled off from the silicone adsorption layer 2, and the silicone adsorption layer 2 is attached to the surface of the adherend.

(Heat melting ink ribbon Y)
Among the thermal transfer ribbons, a thermal melting ink ribbon can be suitably used for the thermal transfer image-receiving sheet X of the present invention. The heat melting ink ribbon Y used in the present invention is made of an epoxy resin, an ethylene-vinyl acetate copolymer resin, and a modified polypropylene resin so as to be at least the uppermost layer in contact with the image receiving layer 4 of the thermal transfer image receiving sheet X at the time of thermal transfer. Provided with a transfer layer 5 containing a resin selected from the group consisting of The image receiving layer 4 of a thermal transfer image receiving sheet X formed by curing a composition containing a urethane acrylate having a polybutadiene skeleton with a urethane acrylate as a main agent is provided on the uppermost layer of the heat melting ink ribbon Y in contact with the image receiving layer 4 By combining the transfer layer 5 containing a resin selected from the group consisting of an epoxy resin, an ethylene-vinyl acetate copolymer resin, and a modified polypropylene resin, the above-mentioned remarkable effects can be obtained. That is, by combining these, the excellent scratch resistance of the image receiving layer 4, the excellent printing performance by the heat melting ink ribbon Y of the image receiving layer 4, and the excellent printing image printed by the heat melting ink ribbon Y It is possible to provide a set of a thermal transfer image-receiving sheet and a heat-meltable ink ribbon which have both scratch resistance.

(Transfer layer 5)
The transfer layer 5 may or may not have a colorant, but when it does not have a colorant, a colored layer can be provided between the transfer layer 5 and the substrate 7. Here, an embodiment in which the transfer layer 5 is a colored transfer layer having a coloring agent will be described as the heat melting ink ribbon Y which is one of the embodiments of the present invention.

The transfer layer 5 in the present invention is the same as the conventional (colored) transfer layer in that it is composed of a coloring agent and a vehicle containing a thermoplastic resin as an essential component.

Examples of the vehicle include those containing a thermoplastic resin and, if necessary, compounded with a waxy substance, a dispersing agent, an extender pigment and the like. In the transfer layer 5 of the present invention, the content of the thermoplastic resin in the solid content of the transfer layer 5 is such that the printability of the thermal transfer image receiving sheet X on the image receiving layer 4 by the heat melting ink ribbon Y is excellent. 35 weight% or more is preferable and 50 weight% or more is more preferable. In order to improve the printability of the heat transfer type ink ribbon Y to the image receiving layer 4 of the thermal transfer image receiving sheet X, an extender pigment may be blended.

The softening point of the transfer layer 5 is preferably about 50 to about 170.degree.

As described above, the thermoplastic resin is a resin selected from the group consisting of an epoxy resin, an ethylene-vinyl acetate copolymer resin, and a modified polypropylene resin, and is usually one type, but contains two or more types. You can also

Examples of the wax-like substance include natural waxes such as wax wax, bees wax, carnauba wax, candelilla wax, montan wax and ceresin wax; petroleum waxes such as paraffin wax and microcrystalline wax; oxidized wax, ester wax, polyethylene Synthetic waxes such as waxes, Fischer-Tropsch waxes, α-olefin-maleic anhydride copolymer waxes; higher fatty acids such as myristic acid, palmitic acid, stearic acid, behenic acid; higher fatty alcohols such as stearyl alcohol, docosanol; higher fatty acids Monoglycerides, fatty acid esters of sucrose, esters such as fatty acid esters of sorbitan; amides such as stearic acid amide and oleylamide, and one kind such as bisamides The other is two or more of them can be used.

As the colorant, any colorant conventionally used as a colorant of this type of heat-meltable ink can be used, and various pigments and dyes such as carbon black and inorganic and organic dyes can be suitably used. The content of the colorant in the ink layer is preferably 10 to 50%.

The application amount of the transfer layer 5 is preferably 0.5 to 6 g / m ² .

(Release layer 6)
In the heat melting ink ribbon Y, the transfer layer 5 and the base 7 are such that the transfer layer 5 is reliably released from the base 7 and transferred to the image receiving layer 4 of the thermal transfer image receiving sheet X when printing with a printer. Preferably, the release layer 6 is provided between the two. As the releasing layer 6 in the present invention, a conventional heat-melting releasing layer containing a wax-like substance as a main component can be used without particular limitation. As the waxy substance, those exemplified for the transfer layer can be used.

Among the above-mentioned substances, the wax-like substance used for the releasing layer 6 preferably has a softening point of 60 to 90 ° C., a penetration of 2 or less, and a viscosity of 5 to 100 cps (90 ° C.). Examples thereof include candelilla wax, carnauba wax, montan wax, Fischer-Tropsch wax, ester wax, paraffin wax, polyethylene wax and the like.

In addition to the wax-like substance, fillers, oils, fatty acids and the like may be added to the release layer 6 as necessary.

The release layer 6 may be formed by a hot melt coating method, or may be formed by applying a coating liquid comprising a solvent solution of waxy substance, a dispersion, an emulsion, etc. on a substrate and drying it. Good.

The coating amount of the release layer 6 is preferably in the range of 0.1 to 4 g / m ² . If the coating amount is less than the above range, the peeling effect is poor, and if it is more than the above range, the thermal diffusion becomes large, which is not preferable.

(Base 7)
The base 7 of the heat melting ink ribbon Y is a polyester film such as a polyethylene terephthalate film, a polyethylene naphthalate film, a polyarylate film, a polycarbonate film, a polyamide film, an aramid film, and a film for a base of this kind of ink ribbon. Various plastic films generally used as can be used. The thickness of the substrate is preferably 1 to 10 μm, more preferably 2 to 7 μm from the viewpoint of improving the heat conduction.

(Heat resistant slip layer 8)
When the plastic film is used as the substrate 7, its rear surface (surface on the side in sliding contact with the heating head) is modified with silicone resin, fluorocarbon resin, nitrocellulose resin, or these, for example, silicone modified urethane resin, silicone It is preferable to provide a conventionally known heat-resistant slip layer 8 made of various heat-resistant resins such as modified acrylic resin, or those obtained by mixing these heat-resistant resins with a lubricant.

Hereinafter, the present invention will be described in detail by way of examples and comparative examples, but the present invention is not limited to the following examples. In the Examples and Comparative Examples, "parts" are by weight unless otherwise specified.

As the TPU base material 3, a base material having a thickness of 100 μm of Esmer (registered trademark) URS PX98 manufactured by Nippon Mata Co., Ltd. was prepared.

(Anchor layer 4A)
The materials shown in Table 1 were mixed and stirred in the amounts shown in Table 1 to prepare an anchor layer 4A coating liquid. The anchor layer 4A coating liquid of Table 1 was coated and dried on the TPU substrate 3 so that the thickness after drying was 1.0 μm, and the anchor layer 4A was laminated on the TPU substrate 3. With regard to the TPU substrate 3 with the films attached on both sides, the film is passed through the coating machine in a state where only the film to which the anchor layer 4A is to be applied is peeled off. This is because the strength of the TPU base material alone is weak, and there is a possibility that the TPU base material may extend during traveling in a coating machine.

(Water dispersion of polyester polyol A)
An aqueous dispersion of polyester polyol A used for the anchor layer 4A coating liquid was produced by the method shown below.

  Distillation pipe, nitrogen inlet pipe, thermometer, four-necked flask equipped with a stirrer 854 parts of dimethyl terephthalate, 355 parts of 5-sodium sulfoisophthalic acid, 186 parts of ethylene glycol, 742 parts of diethylene glycol, as a reaction catalyst Then, add 1 part of zinc acetate, raise temperature from 130 ° C to 170 ° C over 2 hours, carry out transesterification, add 730 parts of isophthalic acid and 1 part of antimony trioxide, and add 2 hours from 170 ° C to 200 ° C. The temperature was raised to carry out the esterification reaction. Then, the temperature was raised gradually and the pressure was reduced gradually, and finally the polycondensation reaction was carried out at a reaction temperature of 250 ° C. and a degree of vacuum of 5 mmHg or less for 1 hour to obtain a polyester polyol A.

  25 parts of the obtained polyester polyol A was charged in a mixed solution of 15 parts of isopropanol and 60 parts of ion-exchanged water and stirred at 70 to 80 ° C. for 3 hours to obtain an aqueous dispersion of polyester polyol A having a solid content concentration of 25%. .

(Image receiving layer 4)
In preparation for the formation of the image receiving layer 4, first, urethane acrylate having a polybutadiene skeleton is synthesized.

(Synthesis of urethane acrylate having polybutadiene backbone)
In a 5-liter four-necked flask, 1943 parts by weight of polybutadiene glycol (manufactured by Nippon Soda Co., Ltd., trade name: NISSO PB G-3000, number average molecular weight 2600 to 3200), 0.2 weight of di-n-butyl tin dilaurate 0.7 parts by weight of 2,6-di-tert-butyl-4-methylphenol is added, and while stirring at 50 ° C., isophorone diisocyanate (Sumitomo Bayer Co., Ltd., trade name Desmodul I) 289 parts by weight was added dropwise over 4 hours.

  After completion of the addition, the reaction is continued for 3 hours while stirring at 50 ° C., and then 388 parts by weight of pentaerythritol triacrylate is added dropwise over 2 hours while stirring at 50 ° C. The reaction was continued for 5 hours to obtain urethane acrylate A having a polybutadiene skeleton.

[Formation of image receiving layer]
The urethane acrylate A having a polybutadiene skeleton synthesized above, a mixture of dipentaerythritol hexaacrylate and a urethane acrylate oligomer, acryloyl morpholine, a fluorine-based leveling agent, a photopolymerization initiator, and butyl acetate as a solvent, as shown in Table 2 each image receiving layer coating liquid was adjusted after coating drying each image receiving layer coating solution shown in Table 2 on the anchor layer 4A of TPU substrate 3, was irradiated with ultraviolet light at an accumulated light intensity of 500 mj / cm ² each, The coated film was cured to form a layer having a layer thickness shown in Table 2, and image receiving layers (hard coat layers) of Examples 1 to 9 and Comparative Examples 1 to 5 were formed.

表１中の各成分の材料名
※１：アクリロイルモルホリン
※２：Ａ−９５５０（ジペンタエリスリトールヘキサアクレート、新中村化学製）とＵＡ−５３（ウレタンアクリレートオリゴマ−、新中村化学製）の１：１混合物
※３：ポリブタジエン骨格を有するウレタンアクリレ−トＡ
※４：フッソ系レベリング剤
※５：光重合開始剤イルガキュアＩＣ１８４−ＢＡ５０（光重合開始剤、チバスペシャリティケミカル製）
※６：酢酸ブチル（溶媒）

Material name of each component in Table 1 * 1: 1 of acryloyl morpholine * 2: A-9550 (dipentaerythritol hexaacrylate, produced by Shin-Nakamura Chemical Co., Ltd.) and UA-53 (urethane acrylate oligomer, produced by Shin-Nakamura Chemical Co., Ltd.) : 1 mixture * 3: urethane acrylate A having a polybutadiene backbone
※ 4: Fluoro leveling agent ※ 5: Photo initiator IRGACURE IC184-BA50 (photo initiator, made by Ciba Specialty Chemicals)
※ 6: butyl acetate (solvent)

(Anchor layer 2A)
(Polyester resin)
36.0 molar parts of terephthalic acid (TPA) as polyvalent carboxylic acid component, 4.0 molar parts of adipic acid (ADA), 36.0 molar parts of ethylene glycol (EG) as polyhydric alcohol component, neopentyl glycol The reaction vessel is charged with 11.5 parts by mole of NPG and 6.0 parts by mole of bisphenol A / ethylene oxide adduct as raw material components in a reaction vessel, and under a nitrogen atmosphere, pressure of 0.3 MPa, temperature of 260 ° C., esterification reaction for 3.5 hours Did. 2.5 × 10 ^-4 mol of antimony trioxide / 1 mol of polyvalent carboxylic acid component is added to the obtained esterified product, the pressure is reduced to 0.5 hPa, and a polycondensation reaction is carried out at 280 ° C. for 3 hours to obtain a polyester resin. The Next, 5.5 mol parts of trimellitic anhydride (TMA) and 1.0 mol part of isophthalic acid (IPA) are added as a depolymerization agent, and depolymerization is carried out at 250 ° C. for 2 hours under normal pressure to obtain terephthalic acid ( TPA) / adipic acid (ADA) / trimellitic anhydride (TMA) / isophthalic acid (IPA) / ethylene glycol (EG) / neopentyl glycol (NPG) / bisphenol A / ethylene oxide adduct = 32.0 / A polyester resin of 4 / 5.5 / 1.0 / 40.0 / 11.5 / 6.0 (molar ratio) was obtained. The above polyester resin was dissolved in an aqueous solution containing ammonia and an aqueous solution equivalent to 5% of butyl cellosolve to prepare an aqueous solution of 20% polyester resin, and the solution was stirred at a rotational speed of 7,000 rpm. Next, hot water was passed through a jacket of a stirrer and heated, and the system temperature was maintained at 73 to 75 ° C. and stirred for 60 minutes. Thereafter, cold water was poured into the jacket, and the rotational speed of the stirring blade was lowered to 5,000 rpm, and the mixture was cooled to room temperature (about 25 ° C.) while stirring to obtain an aqueous polyester resin solution (solid content 20% by weight). The acid value of the polyester resin was 91 mg KOH / g. The acid value of the resin was determined by titrating an aqueous solution of acid value polymer with 1/10 N KOH aqueous solution using phenolphthalene as an indicator to neutralize 1 g of polymer. The number of mg was determined.

 After adding 90 parts by weight of water and 50 parts by weight of the polyester resin solution (solid content 20% by weight) of the above production example and sufficiently stirring and mixing with a high speed mixer, 50 parts by weight of methanol is gradually added while stirring to obtain an anchor layer. It was set as 2A coating liquid. The remaining PET film is peeled off from the TPU substrate of each of the Examples and Comparative Examples coated with the image receiving layer 4 described above, and the coating solution of anchor layer 2A is coated on the surface of the TPU substrate 3 from which the PET film is peeled. After drying, an anchor layer 2A having a thickness of 0.4 μm was formed.

(Silicone adsorption layer 2)
After applying the silicone adsorption layer coating solution shown in Table 3 with an application thickness of 20 μm (after drying) on the above anchor layer 2A under an environment of 23 ° C. and 50% RH, the oven 150 ° C. 100 The silicone adsorption layer 2 was obtained by crosslinking in seconds.

(Separator A1)
In order to protect the surface, a PET film (Lumirror (registered trademark) 50 μ thick) was attached to the silicone adsorption layer as a separator A1.

(Heat melting ink ribbon Y)
Next, heat melting ink ribbons Y used in Examples 1 to 9 and Comparative Examples 1 to 5 were produced. An ester wax is applied on the surface of a substrate 7 which is a polyethylene terephthalate film having a thickness of 6 μm on which a silicone-modified acrylic resin layer having a thickness of 0.1 μm is formed as the heat resistant slip layer 8 on the back surface. A release layer 6 of 0. 0 g / m ² was formed. Then, a transfer layer coating liquid having a formulation shown in the following Table 4 was coated on the release layer 6 and dried to form a transfer layer 5 having a coating amount of 2.0 g / m ² .

※１：エチレン−酢酸ビニル共重合体
※２：エポキシ樹脂
※３：変性ＰＰ樹脂
※４：エステルワックス
※５：エステルワックスとテルペン樹脂の１：１混合物
※６：石油樹脂
※７：カーボンブラック
※８：トルエン（溶媒）

* 1: Ethylene-vinyl acetate copolymer * 2: Epoxy resin * 3: Modified PP resin * 4: Ester wax * 5: 1: 1 mixture of ester wax and terpene resin * 6: Petroleum resin * 7: Carbon black * 8: Toluene (solvent)

  The evaluation results of the respective examples and comparative examples are shown in Table 5, and the respective evaluation methods are shown below.

(Evaluation method)
(Print evaluation)
Print evaluation was performed using a thermal transfer printer B-EX4T1 manufactured by Toshiba TEC in combination of the thermal transfer image receiving sheet X of each example and comparative example and the thermal melting ink ribbon Y. Printing was carried out with the same predetermined printing pattern under the conditions of printing energy setting +10 of the printer and printing speed of 127 mm / sec, and the presence or absence of occurrence of blurring was confirmed, and the results were judged according to the following criteria. The following evaluation was not performed for those for which the print evaluation judgment was x.
Judgment criteria ◎: There are no print defects or non-transferable parts in a solid part.
○: There is a minute chipping on the print or a part that can not be transferred, but there is no problem in practical use.
X: There is a missing part in the printing or a part where transfer can not be made in the solid part.

(Surface tracking evaluation)
The thermal transfer image-receiving sheet X of each example and comparative example cut to the size of 1.50 mm x 50 mm is prepared.
2. After the separator A1 of the thermal transfer image receiving sheet X prepared in item 1 is peeled off, the silicone adsorption layer 2 is attached to a smartphone having a curved surface at the end of the screen display surface. The thermal transfer image-receiving sheet X is attached to the smartphone so that air bubbles do not enter between the silicone adsorption layer 2 and the smartphone.
3. A jig made of expanded polystyrene processed so as to fit the curved surface shape of the smartphone is prepared, and the thermal transfer image-receiving sheet X attached is pressed against the smartphone using a force of 10 N for 60 seconds using this jig.
4. After releasing the pressing of the jig, after 60 minutes, it is confirmed whether or not the thermal transfer image receiving sheet X is lifted at the curved surface portion of the smartphone.
Evaluation criteria ○: No rise after 60 minutes.
Δ: After 60 minutes, part of the curved surface part is lifted.
X: After 60 minutes, all of the curved surface portions are lifted.

(Abrasion resistance evaluation)
Steel wool (Nippon Steel Wool Co., Ltd.) with a load of 1 N / cm ² applied to the surface of the image receiving layer (hard coat) of the thermal transfer image receiving sheet X of each Example and Comparative Example printed on the surface of the image receiving layer by printing evaluation. The surface condition of the image-receiving layer after rubbing with Bonster No. 0000) was visually evaluated and evaluated according to the following evaluation criteria.
(Evaluation criteria)
◎: There is no scratch.
:: A slight abrasion occurs on the print but it is not noticeable. There is no scratch on the image receiving layer.
X: The print and the image receiving layer are scratched, and the scratch can be easily confirmed visually.

(Cracking evaluation)
The thermal transfer image-receiving sheet X of each Example and Comparative Example printed on the surface of the image receiving layer in the printing evaluation is cut out to a size of 10 mm width × 150 mm length so that the sample measurement site becomes 10 mm width × 100 mm length (stretching direction) Set the sample and stretch it at a tensile speed of 100 mm / min by 120% using a tensile tester (Autograph manufactured by Shimadzu Corporation) under an environment of 25 ° C and 50% RH, and the presence or absence of cracks in the print and image receiving layer Visually assess.
(Evaluation criteria)
◎: No cracks occur in the print and the image receiving layer.
○: Slight cracks in the print but not noticeable. There is no cracking in the image receiving layer.
X: Cracking occurs in the print and the image receiving layer, and the crack can be easily confirmed visually.

(Evaluation of floating)
The thermal transfer image-receiving sheet X of each Example and Comparative Example printed on the surface of the image receiving layer in the printing evaluation is cut out to a size of 10 mm width × 150 mm length so that the sample measurement site becomes 10 mm width × 100 mm length (stretching direction) Set the sample and stretch it at a tensile speed of 100 mm / min by 120% using a tensile tester (Autograph manufactured by Shimadzu Corporation) under an environment of 25 ° C and 50% RH, and the presence or absence of floating of the print and image receiving layer Visually assess.
(Evaluation criteria)
○: no floating occurs on the print and the image receiving layer.
X: Lifting occurs in the printing and / or the image receiving layer.

FIG. 2 is a schematic view showing a layer configuration of a thermal transfer image receiving sheet X and a thermal melting ink ribbon Y according to an embodiment of the present invention.

X: Thermal transfer image-receiving sheet Y: Thermal melting type ink ribbon 1: Separator A
2: Silicone adsorption layer 2A: anchor layer 3: TPU substrate 4A: anchor layer 4: image receiving layer (hard coat layer)
5: Transfer layer 6: Release layer 7: Base material 8: Heat-resistant slip layer

Claims (6)

A set of a thermal transfer image receiving sheet in which an image receiving layer is laminated on one surface of a thermoplastic urethane elastomer substrate and a heat melting ink ribbon for thermally transferring the ink to the image receiving layer, wherein the image receiving layer is mainly composed of urethane acrylate. A layer formed by curing a composition in which a part of the urethane acrylate is a urethane acrylate having a polybutadiene skeleton, the thickness of the image receiving layer is 0.8 μm or more and 2.0 μm or less, and the image receiving layer at the time of thermal transfer A transfer layer, which is the uppermost layer of the heat melting ink ribbon in contact with the ink, contains a resin selected from the group consisting of an epoxy resin, an ethylene-vinyl acetate copolymer resin, and a modified polypropylene resin It is a set of a sheet and a heat melting type ink ribbon. The transfer layer, which is the uppermost layer of the heat melting ink ribbon in contact with the image receiving layer at the time of the thermal transfer, is a resin selected from the group consisting of epoxy resin, ethylene-vinyl acetate copolymer resin, and modified polypropylene resin in solid content The set of the thermal transfer image-receiving sheet and the heat-meltable ink ribbon according to claim 1, characterized in that it contains 35% by weight or more. 3. The thermal transfer image-receiving sheet according to claim 1, wherein an adhesive layer or an adsorption layer is laminated on the surface of the thermoplastic urethane elastomer substrate opposite to the surface on which the image-receiving layer is laminated. Set of heat melting type ink ribbons. The adsorption layer is characterized in that a silicone composition comprising a diorganopolysiloxane having two or more alkenyl groups in one molecule and an organohydrogenpolysiloxane is cured by an addition reaction as a main component. A set of the thermal transfer image receiving sheet according to claim 3 and a heat melting type ink ribbon. The diorganopolysiloxane is a linear diorganopolysiloxane having a vinyl group at both ends, a linear diorganopolysiloxane having a vinyl group at both ends and a side chain, and a branched group having a vinyl group at only the end. The set of the thermal transfer image-receiving sheet according to claim 4 and the thermal melting type ink ribbon according to claim 4, which is at least one selected from diorganopolysiloxanes and branched diorganopolysiloxanes having vinyl groups at the terminal and side chains. The thickness of the said thermoplastic urethane elastomer base material is 50 micrometers or more and 150 micrometers or less, The set of the thermal transfer image receiving sheet and heat-fusion-type ink ribbon in any one of Claims 1-5.

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