JP6712755B2 - Thermal transfer image receiving film - Google Patents

Description

The present invention relates to a thermal transfer image-receiving film for printing using a thermal fusion type transfer recording medium. More specifically, the present invention relates to a thermal transfer image receiving film that can be easily attached to and detached from a three-dimensional curved surface by following the surface of an adherend having a curved shape.

2. Description of the Related Art Conventionally, there is a thermal transfer image-receiving film which prints on a film provided with a pressure-sensitive adhesive layer by a thermal transfer recording method and is attached to various adherends. These are mainly formed in a tape shape, and after printing is performed using a heat-melt transfer recording medium, they are attached to various adherends and used for display applications and the like.

In recent years, there have been cases where the adherend is required to be attached to a three-dimensional curved surface. In such a case, the image receiving film is required to have conformability to the shape of the adherend, that is, the flexibility and elongation of the image receiving film. As an example of a thermal transfer image-receiving film for a heat-melting transfer recording medium, which has followability to an adherend having a non-planar shape such as an uneven surface or a spherical surface, or a non-flat surface, and which can form an image uniformly, Document 1 describes a thermal transfer image-receiving film comprising a urethane-based resin film containing a thermoadhesive resin/adhesive/separator film. Further, Patent Document 2 describes a recording sheet composed of a urethane-based resin film/adhesive/separator film having a tensile strength of 20 N/15 mm or less in a range of an elongation rate of 15% or less. Further, Patent Documents 1 and 2 also describe that the adhesive property is such that it can be attached to and removed from an adherend.

As an adhesive layer having an adsorption property that can be easily attached to and removed from an adherend, for example, Patent Document 3 introduces an adhesive layer using a silicone-based adhesive. This is because the pressure-sensitive adhesive is composed of an addition reaction type silicone resin which is thermally crosslinked by a hydroxyl reaction between a vinyl group and a SiH group, and has an excellent property that it can be easily attached and detached and can be repeated many times. It is an adsorptive pressure-sensitive adhesive layer.

Here, the present inventors have printed on a thermal transfer image-receiving film comprising a polyurethane-based elastomer substrate/the pressure-sensitive adhesive layer described in Patent Document 3/separator film using a heat-melt transfer recording medium to obtain an uneven surface or a spherical surface. It has been found that there is a problem in that it can be easily attached and detached with high followability even to an adherend having a non-planar shape or a non-flat surface such as, and can be repeated many times. ..

As described in "Urethane-based resin film containing heat-adhesive resin" in Patent Document 1, the polyurethane-based elastomer base material itself does not necessarily have good adhesion to other resins. In particular, when the silicone-based pressure-sensitive adhesive layer is directly laminated on the polyurethane-based elastomer substrate, the adhesion between the polyurethane-based elastomer substrate and the silicone-based pressure-sensitive adhesive layer is weak. When it was attempted to be removed, the base material and the pressure-sensitive adhesive layer were peeled off, and a problem called silicone residue occurred, in which the silicone-based pressure-sensitive adhesive layer remained on the adherend. Patent Documents 1 and 2 do not suggest any solution to this problem. Further, although Patent Document 3 describes that a primer layer may be provided when laminating a silicone-based pressure-sensitive adhesive layer on a substrate, a specific method for laminating the silicone-based pressure-sensitive adhesive layer on a polyurethane-based elastomer substrate will be described. There is no specific description. As a result, a silicone-based pressure-sensitive adhesive layer is laminated on a polyurethane-based elastomer substrate, attached to the adherend by following a curved surface, and easy to remove, and at the time of removal, peel off between the pressure-sensitive adhesive layer and the substrate. Thus, there has been no thermal transfer image-receiving film capable of being smoothly peeled off from an adherend or a laminated structure without generating a silicone residue on the adherend.

JP-A-5-8550 JP, 2005-292606, A JP, 2004-299185, A

The present invention is to solve the above-mentioned problems, in which a silicone-based pressure-sensitive adhesive layer is laminated on a thermal transfer image-receiving film made of a polyurethane-based elastomer substrate, and it is easily attached and removed by following a curved surface of an adherend. The thermal transfer image-receiving film capable of being smoothly peeled off from the adherend or the laminated structure without peeling between the pressure-sensitive adhesive layer and the base material to generate a silicone residue on the adherend when detached. To provide.

According to a first aspect of the present invention, thermal transfer recording is performed on a film obtained by laminating a pressure-sensitive adhesive layer and a separator film on one surface of a polyurethane elastomer substrate in this order, and using a heat-melt transfer recording medium on the other surface of the substrate. in the thermal transfer image-receiving film for use in the printing method of performing the crosslinking addition reaction type silicone resin pressure-sensitive adhesive layer is thermally crosslinked by hydrosilylation reaction between organohydrogenpolysiloxane having a polyorganosiloxane and SiH groups having a vinyl group The thermal transfer image-receiving film is characterized in that an anchor layer made of an acrylic modified polyester resin having an acid value of 7 to 100 mgKOH/g is provided between the base material and the pressure-sensitive adhesive layer.

A second invention is a thermal transfer recording system characterized by printing on the thermal transfer image-receiving film according to the first invention by using a thermal fusion type transfer recording medium having at least a thermal adhesive layer on a substrate. ..

A third invention is the thermal transfer recording method according to the second invention, characterized in that the thermoplastic polyester resin content in the thermal adhesive layer is 50 to 100% by weight. is there.

A fourth invention is the thermal transfer recording method according to the second and third inventions, wherein the thermal transfer image-receiving film is a tape-shaped member and printing is performed by a tape printer that prints print data on the tape-shaped member. This is a thermal transfer recording method characterized by the above.

According to the present invention, it is possible to provide a thermal transfer image-receiving film which can be attached to an adherend by following a curved surface and can be easily removed, and the base material and the silicone-based pressure-sensitive adhesive layer are not separated.

The thermal transfer image-receiving film of the present invention will be described in more detail below.

(Thermal transfer image-receiving film)
The thermal transfer image-receiving film of the present invention is a film obtained by laminating a pressure-sensitive adhesive layer on one surface of a polyurethane elastomer substrate and a separator film in this order, and using a heat-melt transfer recording medium on the other surface of the substrate. In a thermal transfer image-receiving film used in a printing method for thermal transfer recording, the pressure-sensitive adhesive layer is made of an addition reaction type silicone resin which is thermally crosslinked by a hydroxyl reaction between a vinyl group and a SiH group, and the base material and the pressure-sensitive adhesive layer are An anchor layer made of an acrylic modified polyester having an acid value of 7 to 100 mgKOH/g is provided between them.

(Base material)
As the polyurethane-based elastomer substrate in the present invention, a polyurethane-based resin obtained by thermally crosslinking ordinary polyols with isocyanate is used.

Examples of the polyols include polyether-based polyols, polycarbonate-based polyols, polyester-based polyols and the like. Examples of the polyether polyol include polyethylene glycol or triol, polypropylene glycol or triol, polybutylene glycol or triol, polytetramethylene glycol or triol, and addition polymers and block copolymers of these oxyalkylene compounds having different carbon numbers. Examples include coalescence.

Examples of the polycarbonate-based polyol include a polycarbonate-based polyol obtained by using only dialkyl carbonate and 1,6-hexanediol, 1,6-hexanediol, 1,4-butanediol, and 1,5-pentanediol. Another example is a polycarbonate-based polyol obtained by using a diol obtained by copolymerizing 1,4-cyclohexanedimethanol and dialkyl carbonate.

Examples of the polyester polyol include aliphatic glycols such as ethylene glycol, propylene glycol, butanediol, pentanediol, hexanediol, heptanediol, decanediol, and cyclohexanedimethanol, and succinic acid, adipic acid, sebacic acid, Fumaric acid, suberic acid, azelaic acid, 1,10-decamethylenedicarboxylic acid, aliphatic dibasic acids such as cyclohexanedicarboxylic acid, and the like, aliphatic polyester-based polyols reacted as an essential raw material component, ethylene glycol, propylene glycol, Aromatic polyester polyols obtained by reacting aliphatic glycols such as butanediol with aromatic dibasic acids such as terephthalic acid, isophthalic acid, and naphthalene dicarboxylic acid as essential raw materials, and cyclic esters (especially caprolactone) are opened. Examples include polyester-based polyols obtained by reacting the glycol obtained by cyclization with the above aliphatic dibasic acid or aromatic dibasic acid.

The polyisocyanate used as the raw material of the polyurethane resin is not particularly limited as long as it is a polyisocyanate having two or more isocyanate groups in one molecule, and aromatic diisocyanate, aromatic polyisocyanate, aliphatic diisocyanate, Aliphatic polyisocyanate, alicyclic diisocyanate, alicyclic polyisocyanate and the like can be used, but the higher the number of reactive groups added in one molecule, the higher the hardness and the tendency to follow the curved surface. Therefore, diisocyanate is preferably used.

Examples of the diisocyanate include aromatic diisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate, p-phenylene diisocyanate, m-phenylene diisocyanate, p-xylene diisocyanate and m-xylene diisocyanate, and aliphatic diisocyanates such as ethylene diisocyanate. Trimethylhexamethylene diisocyanate, hexamethylene diisocyanate, etc., as alicyclic diisocyanates, isophorone diisocyanate, hydrogenated diphenylmethane diisocyanate, norbornene diisocyanate, and the like, among them, from the viewpoint of durability, non-yellowing diisocyanate having durable yellowing More preferable.

The non-yellowing diisocyanate is an aliphatic or alicyclic diisocyanate having no isocyanate group directly bonded to an aromatic nucleus, and examples thereof include hexamethylene diisocyanate, isophorone diisocyanate, hydrogenated diphenylmethane diisocyanate and the like. Further, polyfunctional isocyanates such as isocyanurate type, burette type and adduct type which are multimers of hexamethylene diisocyanate may be used. The isocyanate may be only one kind or two or more kinds. Further, an isocyanate having a functional group blocked so as not to react up to a certain temperature may be used.

The polyurethane resin may be cross-linked or modified with a known chain extender or cross-linking agent such as a polyvalent amine, if necessary. For example, a polyurethane urea resin modified with the polyvalent amine may be used, or a urethane resin may be used as a thermoplastic elastomer by using the polyvalent amine as a chain extender. Examples of the thermoplastic urethane elastomer include an elastomer having an aliphatic polyether or polyester as a soft segment and a polyurethane unit of a short chain glycol as a hard segment.

In the present invention, among the above polyols, polycarbonate-based polyols and polyester-based polyols are preferably used because of the ease of obtaining a flexible base material that follows a curved surface and the adhesiveness with a thermal transfer print image. In particular, a polycaprolactone-based urethane elastomer obtained by thermally crosslinking a polycaprolactone-based polyol obtained by ring-opening of caprolactone with diisocyanate is preferably used.

The raw materials for the polyurethane resin may be used alone or in combination of two or more. Also, if necessary, stabilizers such as hiding pigments, ultraviolet absorbers, antioxidants, light stabilizers, urethanization catalysts, colorants, flame retardants, antistatic agents, additives such as surfactants, and thermal adhesiveness. Resin may be added.

The thickness of the polyurethane elastomer substrate in the present invention is preferably 25 μm or more and 200 μm or less, and more preferably 50 μm or more and 180 μm or less. If the thickness of the elastomer base material is less than 25 μm, printing and handling after printing become difficult, and if it exceeds 200 μm, it is wasteful in terms of cost. The elongation at break of the elastomer substrate is preferably more than 120%, more preferably more than 300%. If the elongation at break is less than 120%, the thermal transfer image-receiving film loses flexibility and the curved surface followability deteriorates.

(Silicone adhesive layer)
As the pressure-sensitive adhesive layer of the thermal transfer image-receiving film of the present invention, a silicone-based pressure-sensitive adhesive layer is preferably used because it has the property that it can be easily attached and detached and can be repeated many times. The silicone used for the silicone-based pressure-sensitive adhesive layer is required to have flexibility like rubber. And as the performance of the silicone-based pressure-sensitive adhesive layer, the surface of the pressure-sensitive adhesive layer follows the surface of the adherend, and when peeled from the adherend, the pressure-sensitive adhesive layer is easily separated from the surface of the adherend with a small peeling force. It is required to be peelable. Further, as the processing performance of silicone used for the silicone-based pressure-sensitive adhesive layer, a cross-linked silicone-based pressure-sensitive adhesive layer having a film thickness of at least 10 μm is provided only by coating and heat treatment without using a method of weighting. Be required to be. Such silicones include addition type liquid silicone resins that are transparent, have excellent heat resistance and compression set characteristics, and have a low viscosity and that are liquid type that are crosslinked to a deep portion in a short time at a low temperature of 150° C. or less during a curing reaction. Use is preferred. Addition type liquid silicone resin, based on such as platinum catalysts, can be thermally crosslinked by hydrosilylation reaction between organohydrogenpolysiloxane having a SiH group as polyorganosiloxane and crosslinking agent having a vinyl group.

Examples of such a silicone include a silicone composed of a linear polyorganosiloxane having vinyl groups only at both ends, a silicone composed of a linear polyorganosiloxane having vinyl groups at both ends and side chains, and It is preferable to use a silicone obtained by crosslinking at least one silicone selected from the group consisting of a branched polyorganosiloxane having a vinyl group and a silicone composed of a branched polyorganosiloxane having a vinyl group at the terminal and side chains. ..

One form of these silicones is a linear diorganopolysiloxane having vinyl groups only at both ends, which is represented by the following general formula (Formula 1). Another form is a branched diorganopolysiloxane having vinyl groups only at both ends, which is represented by the following general formula (Formula 2).

(In the formula, R represents the following organic group, and n represents an integer)

(In the formula, R represents the following organic group, and n and m 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 a methyl group, an ethyl group and a propyl group, and an aryl group such as a phenyl group and a tolyl group. Or a monovalent hydrocarbon group excluding the same or different unsubstituted or substituted aliphatic unsaturated group in which some or all of the hydrogen atoms bonded to the carbon atoms of these groups are substituted with a halogen atom, a cyano group or the like. Preferably, at least 50 mol% thereof is a methyl group, but the diorganopolysiloxane may be a single type or a mixture of two or more types.

Silicone composed of a linear polyorganosiloxane having vinyl groups at both ends and side chains is a compound in which a part of R in the general formula (Formula 1) is a vinyl group. The silicone composed of a branched polyorganosiloxane having vinyl groups at the terminals and side chains is a compound in which a part of R in the general formula (Formula 2) is a vinyl group.

The cross-linking agent used in the cross-linking reaction here may be a known one. Examples of the cross-linking agent include organohydrogenpolysiloxane. The organohydrogenpolysiloxane has at least three hydrogen atoms bonded to silicon atoms in one molecule, but from the practical viewpoint, one having two ≡SiH bonds in the molecule accounts for 50% by weight of the total amount. It is preferable that the remainder contains at least three ≡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. And complex salts with it. The crosslinked silicone layer has flexibility like silicone rubber, and this flexibility facilitates adhesion to the adherend.

The shape of the commercially available product of the silicone according to the present invention includes a solventless type, a solvent type and an emulsion type, and any type can be used. Among them, the solventless type is very advantageous in terms of safety, hygiene and air pollution because it does not use a solvent. However, even if it is a solvent-free type, an organic solvent such as toluene can be added if necessary for the purpose of adjusting the viscosity to obtain a desired film thickness.

As described above, the property of the silicone-based pressure-sensitive adhesive layer is that it has flexibility like rubber and can adhere to the surface of the adherend to secure the adhesive force when it is adhered to the adherend. Desired. When used as a thermal transfer image-receiving film by sticking to an adherend, the thickness of the silicone-based pressure-sensitive adhesive layer is at least 10 μm in order to secure a shearing force in the pressure-sensitive adhesive surface direction of the silicone-based pressure-sensitive adhesive layer to the adherend. As described above, usually 20 to 50 μm is required. When the thickness is 10 μm or less, the shearing force in the adhesive surface direction of the thermal transfer image-receiving film with respect to the adherend cannot be secured, and the thermal transfer image-receiving film is likely to be peeled off from the adherend particularly during long-term sticking.

(Anchor layer)
In the thermal transfer image-receiving film of the present invention, when a silicone-based pressure-sensitive adhesive layer is directly laminated on a polyurethane-based elastomer substrate, sufficient adhesive force cannot be obtained. Therefore, an anchor layer is provided between the polyurethane-based elastomer substrate and the silicone-based pressure-sensitive adhesive layer. Set up. The purpose is to improve the adhesive strength between the base material and the pressure-sensitive adhesive layer, and when the pressure-sensitive adhesive layer is re-peeled after being adhered to various adherends, peeled between the pressure-sensitive adhesive layer and the base material. Then, it is possible to smoothly peel from the adherend or the laminated structure without generating a silicone residue on the adherend.

Examples of the material of the anchor layer include polyester resins, acrylic resins, urethane resins and the like. Among them, acrylic resins are preferable, and acrylic modified polyester resins are particularly preferable from the viewpoint of adhesiveness and coating properties.

As the acrylic modified polyester resin used for the anchor layer, it is preferable to use one having an acid value of 7 to 100 mgKOH/g. In the present invention, since the polyurethane-based elastomer is used as the base material, the anchor layer is required to have adhesiveness to both the polyurethane-based elastomer base material and the silicone-based pressure-sensitive adhesive layer. As a result of diligent study by the present inventor, as a result of using an acrylic-modified polyester-based resin having an acid value in the range of 7 to 100 mgKOH/g for the anchor layer, adhesiveness to both the polyurethane-based elastomer base material and the silicone-based pressure-sensitive adhesive layer The present invention has been accomplished by finding that the above is achieved.

When the acid value of the acrylic-modified polyester resin is less than 7 mgKOH/g, the adhesive strength between the anchor layer and the silicone-based pressure-sensitive adhesive layer, the anchor layer and the polyurethane-based elastomer base material is weak, and the silicone-based pressure-sensitive adhesive layer tends to deteriorate with time. It becomes easy to separate from the polyurethane elastomer substrate. Further, after the thermal transfer image receiving film is adhered to the adherend, when the thermal transfer image receiving film is peeled off, the adhesive force between the adherend surface and the silicone-based pressure-sensitive adhesive layer surface increases with time and the peeling cannot be performed smoothly, and the adherend Silicone residue is likely to occur on the top. If the acid value exceeds 100 mgKOH/g, the water resistance of the resin film will be insufficient.

(Acrylic modified polyester resin)
The acrylic modified polyester resin having an acid value in the range of 7 to 100 mgKOH/g used in the present invention is a polyester produced by a conventional method, for example, by an esterification reaction of a polyvalent carboxylic acid component and a polyvalent hydroxy compound component. Among unsaturated resins, graft polymerization of unsaturated polyester resins and polymerizable (meth)acrylic monomers containing carboxyl group-containing polymerizable unsaturated monomers, or reaction of hydroxyl group-containing polyester resins with acrylic modified fatty acids, etc. can get.

The acrylic-modified polyester-based resin may be used as an anchor layer coating liquid by dissolving a solid component in an organic solvent, but depending on the solvent used, the anchor layer coating liquid may cause the elastomer base material to be eroded by the solvent. is there. Therefore, the anchor layer coating liquid is preferably used as an aqueous dispersion.

The polyvalent carboxylic acid component of the polyester resin is a compound having two or more carboxyl groups in one molecule, and examples thereof include phthalic acid, isophthalic acid, terephthalic acid, 2,6-naphthalenedicarboxylic acid and 4,4′. -Diphenylcarboxylic acid, 1,4-cyclohexanedicarboxylic acid, phenylindanedicarboxylic acid, 4,4'-diphenylsulfonedicarboxylic acid, 4,4'-diphenylmethanedicarboxylic acid, 5-sodiosulfoisophthalic acid, succinic acid, adipic acid , Azelaic acid, sebacic acid, hexahydroterephthalic acid, tetrahydrophthalic acid, hexahydrophthalic acid, maleic acid, fumaric acid, itaconic acid, trimellitic acid, pyromellitic acid, dodecanedicarboxylic acid and the like.

Further, the polyvalent hydroxy compound component is a compound having two or more hydroxyl groups in one molecule, and examples thereof include ethylene glycol, diethylene glycol, propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5. -Pentanediol, 1,6-hexanediol, 2,2-diethyl-1,3-propanediol, neopentyl glycol, 1,9-nonanediol, 1,4-cyclohexanediol, hydroxypivalic acid neopentyl glycol ester, 2-Butyl-2-ethyl-1,3-propanediol, 3-methyl-1,5-pentanediol, 2,2,4-trimethylpentanediol, diols such as hydrogenated bisphenol A, trimethylolpropane, tri Trihydric or higher polyols such as methylolethane, glycerin, and pentaerythritol; 2,2-dimethylolpropionic acid, 2,2-dimethylolbutanoic acid, 2,2-dimethylolpentanoic acid, 2,2-dimethylolhexanoic acid 2,2-dimethylol octanoic acid and other hydroxycarboxylic acids.

As the polymerizable (meth)acrylic monomer used for the acrylic modified polyester resin, methyl (meth)acrylate, ethyl (meth)acrylate, -n-propyl (meth)acrylate, isopropyl (meth)acrylate, (Meth)acrylic acid-n-butyl, (meth)acrylic acid isobutyl, (meth)acrylic acid-tert-butyl, (meth)acrylic acid-n-pentyl, (meth)acrylic acid-n-hexyl, (meth) Cyclohexyl acrylate, n-heptyl (meth)acrylate, n-octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, (meth)acrylic acid 2-hydroxypropyl, phenyl (meth)acrylate, toluyl (meth)acrylate, benzyl (meth)acrylate, 2-methoxyethyl (meth)acrylate, 3-methoxybutyl (meth)acrylate, etc. Can be mentioned.

Examples of the acrylic modified fatty acid used in the acrylic modified polyester resin include lauryl (meth)acrylate, stearyl (meth)acrylate, isostearyl (meth)acrylate, myristyl (meth)acrylate, and natural and synthetic fatty acids. , Beef tallow fatty acid, soybean fatty acid, myristic acid, linseed fatty acid, crotonic acid, coconut fatty acid, tall oil acid, rosin acid, neodecanoic acid, neopentanoic acid, 12-hydroxystearic acid, cottonseed fatty acid, acrylic acid, methacrylic acid, etc. Examples thereof include, but are not limited to, those obtained by reacting an acrylic functional monomer such as methyl methacrylate and isobutyl methacrylate.

Further, α-olefin epoxide such as propylene oxide and butylene oxide, a monoepoxy compound such as glycidyl ester of a highly branched saturated fatty acid may be introduced into the polyester resin by reacting with a carboxyl group in the polyester resin. ..

A hydroxyl group may be introduced into the polyester resin. When a hydroxyl group is introduced, the acrylic layer can be easily modified by reacting with the acrylic modified fatty acid, or the anchor layer can be easily modified by adding a crosslinking reaction agent or the like to the resin. The glass transition temperature of the resin is preferably 0 to 75°C. If the glass transition temperature is lower than 0°C, the coating tends to block and it is difficult to obtain the strength of the coating, and if the glass transition temperature exceeds 75°C, the adhesion with the elastomer substrate may deteriorate. The weight average molecular weight of the polyester resin is preferably 1,000 to 50,000.

The aqueous liquid of the acrylic modified polyester resin can be prepared by a conventionally known method.

When the anchor layer is formed of the acrylic modified polyester resin, the surface resistivity of the anchor layer may exceed 10 ¹³ Ω/□ depending on the environment. In such a case, uneven charging may occur when the silicone-based pressure-sensitive adhesive layer coating liquid is applied onto the anchor layer, and the surface smoothness of the silicone-based pressure-sensitive adhesive layer may be impaired. When the pressure-sensitive adhesive layer is attached to an adherend, air bubbles may be easily generated at the interface between the silicone-based pressure-sensitive adhesive layer and the adherend.

Therefore, in a wide range of temperature and humidity environment, it is preferable to add an antistatic agent, if necessary, for the purpose of preventing uneven charging when the coating liquid for the silicone-based pressure-sensitive adhesive layer is applied onto the anchor layer. ..

When an antistatic agent is added, it is not preferable that the antistatic agent be a catalyst poison when the silicone resin is cured and cause poor curing of the silicone-based pressure-sensitive adhesive layer. From this viewpoint, carbon nanofibers, smectite-based clay minerals, swelling mica, and dissociative layered silicates such as vermiculite are preferable. The layered silicate is particularly preferable because it is available as an aqueous dispersion at low cost. Therefore, also from this viewpoint, it is preferable that the coating liquid made of the acrylic modified polyester resin is an aqueous liquid.

The amount of the antistatic agent added is different depending on the antistatic agent used, but a small amount is preferable from the viewpoint of flexibility of the anchor layer.

The thickness of the anchor layer is preferably 0.1 to 5 μm, more preferably 0.15 to 3 μm. When the thickness of the anchor layer is less than 0.1 μm, the thermally crosslinked silicone-based pressure-sensitive adhesive layer easily separates from the anchor layer, and the anchor layer also easily separates from the elastomer substrate. On the other hand, if the thickness of the anchor layer exceeds 5 μm, the flexibility of the thermal transfer image-receiving film may be impaired and curved surface followability may be deteriorated.

In addition to the above components, the anchor layer coating liquid contains an organic solvent such as an alcohol that is miscible with water within a range that does not impair the dispersibility of the coating liquid in order to improve the wettability to the elastomer substrate. May be added. In addition, as another method, a wettability improver can be added within a range that does not become a catalyst poison for the crosslinking reaction of the addition reaction type silicone resin. In addition, vulcanizing agents, vulcanization accelerators, and the like, which are usually added to compositions of this type, can be added as needed, as long as the effects of the present invention are not reduced.

(Separator film)
The separator film in the present invention is a resin film-made separator film for preventing dirt and foreign matter from adhering to the surface of the silicone-based pressure-sensitive adhesive layer and for improving handling of the thermal transfer image-receiving film. The separator film is used by being attached to the surface of the silicone-based pressure-sensitive adhesive layer. As the separator film, a resin film made of polyethylene terephthalate, polyethylene, polypropylene or the like having a high releasability, and having a surface coated with a release agent, is used if desired. Above all, a resin film made of polyethylene terephthalate is preferably used in terms of cost and availability.

(Heat melting type transfer recording medium)
Examples of the form of the heat-melt transfer recording medium used in the present invention include, for example, thermal adhesive layer/colored layer/(release layer)/base film, coloring material-containing thermal adhesive layer/(release layer). A base film or the like can be used, and a heat-melt transfer recording medium in which at least a thermal adhesive layer is laminated on a base is preferably used.

A conventionally known thermoplastic resin can be used as the thermoplastic resin used in the thermal adhesive layer.
For example, polyester resin, ethylene-vinyl acetate copolymer, ethylene-vinyl butyrate copolymer, ethylene-(meth)acrylic acid copolymer, ethylene-(meth)acrylic acid alkyl ester copolymer, ethylene-acrylonitrile copolymer Copolymers, ethylene-based copolymers such as ethylene acrylamide copolymers and ethylene-styrene copolymers, vinyl chloride-based copolymers such as polyvinyl chloride, vinyl chloride-vinyl acetate copolymers and vinyl chloride-vinyl alcohol copolymers (copolymers ) Polymer, (meth)acrylic ester resin, polyamide resin, epoxy resin, phenol resin, acetophenone-formaldehyde resin, natural rubber, styrene-butadiene copolymer, isoprene polymer, chloroprene polymer, petroleum A resin, a styrene resin, a rosin resin, a terpene resin, a coumarone-indene resin, a thermoplastic polyurethane resin having a melting point or a softening point of 50 to 150° C. is preferably used. These resins may be used alone or in combination of two or more. In particular, a thermal adhesive layer having a thermoplastic polyester resin content of 50 to 100% by weight is more preferable from the viewpoint of image adhesion and fastness to the urethane-based substrate film used in the present invention.

Further, in the heat-adhesive layer of the heat-melt transfer recording medium used in the present invention, waxes, additives and the like are included in the present invention for the purpose of increasing the transfer sensitivity and the adhesion with the polyurethane elastomer substrate. It can be appropriately blended within a range that does not impair the purpose.

Examples of the waxes include lanolin, carnauba wax, candelilla wax, montan wax, ceresin wax, natural wax such as rice wax, paraffin wax, petroleum wax such as microcrystalline wax, oxidized wax, synthetic ester wax, polyethylene wax. , Α-olefin-maleic anhydride copolymer wax, urethanized wax, Fischer-Tropsch wax, synthetic petroleum wax, and other synthetic waxes. These may be used alone or in combination of two or more.

Examples of the additive include a plasticizer, a defoaming agent, a surfactant, and an antioxidant.

As the coloring layer of the heat-melt transfer recording medium used in the present invention, a conventionally known heat-sensitive transfer ink layer comprising a heat-melting or heat-softening vehicle and a coloring agent can be used without particular limitation. As the vehicle, the thermoplastic resins and waxes listed in the description of the thermal adhesive layer may be used alone, or two or more kinds may be used in combination. In addition, the additives listed in the description of the thermal adhesive layer may be appropriately used. From the viewpoint of the robustness of the printed matter, it is preferable to use a thermoplastic resin as a main component.

Examples of the colorant include carbon black, and organic and inorganic color pigments and dyes that are generally used in this kind of heat-melt transfer color layer. The content of the coloring material in the colored layer is preferably 10 to 60% by weight.

In the present invention, the release layer of the heat-melting type transfer recording medium used as necessary contains waxes as a main component. As the waxes to be used, the waxes listed in the description of the thermal adhesive layer may be used alone or in combination of two or more kinds. Further, the thermoplastic resins and additives listed in the description of the thermal adhesive layer may be appropriately used.

Examples of the base material of the heat-melt transfer recording medium used in the present invention include polyester films such as polyethylene terephthalate film and polyethylene naphthalate film, polycarbonate film, polyamide film, aramid film and other heat-melt transfer recording medium of this type. Various plastic films generally used as a film for a substrate can be used. Also, high density thin paper such as condenser paper can be used. The thickness of the substrate is usually about 1 to 10 μm, and in order to improve heat transfer, the range of 1 to 6 μm is preferable.

When the heat-melting type transfer recording medium used in the present invention is used in a printer using a thermal head, a silicone resin, a fluororesin, a nitrocellulose resin, or a resin on the back side of the substrate which slides with the thermal head is used. It is also possible to provide various heat resistant layers modified by, for example, silicone-modified urethane resin, silicone-modified acrylic resin, or the like, or a conventionally known stick preventing layer made of a mixture of these heat-resistant resins with a lubricant.

The heat-melt transfer recording medium used in the present invention can be applied to the case where a heat source other than a thermal head is used as a heat source for heat transfer. For example, a printed type (hot stamp) heated as a heat source can also be used.

Further, by laminating various functional layers on the heat-melting type transfer recording medium of the present invention and transferring to a curved surface following image receiving film, various functional films which can be easily attached to and removed from a curved surface can be prepared. Examples of the functional layer include, but are not limited to, a metal vapor deposition layer, a hard coat layer, a light antireflection layer, and a conductive layer.

Hereinafter, the present invention will be described in detail with reference to Examples and Comparative Examples, but the present invention is not limited to the following Examples. The "parts" in the examples and comparative examples are parts by weight unless otherwise specified. In addition, the acid value of the resin is measured by titrating an aqueous solution of the resin to be measured with a 1/10 normal KOH aqueous solution using phenolphthalein as an indicator, and mg of KOH required to neutralize 1 g of the resin. I asked for the number.

(Anchor layer coating liquid 1)
51.5 parts by weight of terephthalic acid (TPA) as a polyhydric carboxylic acid component, 22.1 parts by weight of isophthalic acid (IPA), 23.0 parts by weight of ethylene glycol (EG) as a polyhydric alcohol component, neopentyl glycol ( 13.3 parts by weight of NPG) was charged as a raw material component into a reaction vessel, and the esterification reaction was carried out under a nitrogen atmosphere at a pressure of 0.3 MPa and a temperature of 260° C. for 3.5 hours. 0.03 parts by weight of antimony trioxide was added to the obtained esterified product, the pressure was reduced to 0.5 hPa, and polycondensation reaction was performed at 280° C. for 3 hours to obtain a polyester resin. Then, 2.1 parts by weight of trimellitic anhydride and 4.0 parts by weight of neopentyl glycol were added as a depolymerizing agent, and depolymerization was performed at 250° C. for 2 hours under normal pressure to obtain terephthalic acid (TPA). /Isophthalic acid (IPA)/trimellitic anhydride (TMA)/ethylene glycol (EG)/neopentyl glycol (NPG)=51.5/22.1/2.1/23.0/17.3( A weight ratio of polyester resin was obtained. The polyester resin was dissolved in water containing 5% of ammonia water and 5% of butyl cellosolve equivalent to the acid value of the polyester resin to prepare a 20% aqueous polyester resin solution, and the mixture was stirred at a rotation speed of 7,000 rpm. Then, hot water was passed through the jacket of the stirrer to heat the system, and the temperature inside the system was maintained at 73 to 75°C, followed by stirring for 60 minutes. Then, cold water was poured into the jacket, the stirring blade was rotated at a rotation speed of 5,000 rpm, and the mixture was stirred and cooled to room temperature (about 25° C.) to obtain an aqueous polyester resin solution (solid content 20% by weight). .. The obtained polyester resin aqueous solution was adjusted to a solid content of 10% by weight, and 90 parts by weight of the aqueous solution was dissolved with 0.1 part by weight of ammonium persulfate as a polymerization initiator, and further 7 parts by weight of methyl methacrylate and ethyl methacrylate were added. After adding 1 part by weight and 2 parts by weight of glycidyl methacrylate and purging with nitrogen, a polymerization reaction was carried out at 70 to 80° C. for 3 hours, and an acrylic modified polyester resin aqueous solution as an anchor layer coating solution 1 (solid content 20% by weight) Got The acid value of the polyester resin was 16 mgKOH/g.

(Anchor layer coating liquid 2)
61.5 parts by weight of terephthalic acid (TPA) as a polyhydric carboxylic acid component, 5.8 parts by weight of adipic acid (ADA), 23.0 parts by weight of ethylene glycol (EG) as a polyhydric alcohol component, neopentyl glycol ( Terephthalic acid (TPA)/TPA/TPA/TPA/TPA/TPA/TPA/TPA/TPA Adipic acid (ADA)/5-sodiosulfoisophthalic acid/ethylene glycol (EG)/neopentyl glycol (NPG)=61.5/5.8/29.7/23.0/15.6 (weight Acrylic modified polyester resin aqueous solution (solid content 20% by weight) was obtained as anchor layer coating solution 2. The acid value of the polyester resin was 3 mgKOH/g.

(Anchor layer coating liquid 3)
Charge ethylene glycol 58.9 parts by weight, trimethylolpropane 6.8 parts by weight, 1,4-cyclohexanedicarboxylic acid 34.4 parts by weight, terephthalic acid 56.4 parts by weight, isophthalic acid 66.4 parts by weight and a polymerization catalyst. The polyester resin having a number average molecular weight of 3,000, a Tg of 40° C., a hydroxyl value of 50 mgKOH/g and an acid value of 0.5 mgKOH/g or less is obtained by performing an esterification reaction while heating and stirring to remove water produced. It was The obtained resin was diluted with cyclohexanone to obtain a polyester resin solution having a solid content of 60%. After 900 parts by weight of the obtained polyester resin solution was charged into a reaction vessel and heated to 130° C., while maintaining the temperature at 130° C., 67.5 parts by weight of methacrylic acid, 67.5 parts by weight of styrene, and 135 parts of ethyl acrylate. By weight, a mixed solution of 11 parts by weight of benzoyl peroxide and 500 parts by weight of cyclohexanone was added dropwise over 4 hours, and at the same time 55 parts by weight of maleic anhydride was added 15 minutes before, 1 hour after and 2 hours after the addition of the above mixed solution. Then, after 3 hours, the reaction mixture was added to the reaction vessel in four batches to carry out polymerization and then cooled to 80° C. to obtain an acrylic modified polyester resin solution. After 80 parts by weight of triethylamine was added to the acrylic modified polyester resin solution to neutralize it, 2,520 parts by weight of deionized water was added over 1 hour with vigorous stirring to add an acrylic modified polyester resin aqueous solution (solid 20% by weight) was obtained as anchor layer coating liquid 3. The acid value of the polyester resin was 85 mgKOH/g.

(Anchor layer coating liquid 4)
900 parts by weight of a polyester resin solution having a solid content of 60% obtained during the preparation of the anchor layer coating liquid 3 was charged into a reaction vessel and heated to 130° C., and then methacrylic acid 135 was maintained at 130° C. A mixed solution of 1 part by weight, 135 parts by weight of styrene, 270 parts by weight of ethyl acrylate, 22 parts by weight of benzoyl peroxide and 700 parts by weight of cyclohexanone was added dropwise over 4 hours, and at the same time 55 parts by weight of maleic anhydride was added dropwise to the above mixed solution. Minutes, 1 hour after dropping, 2 hours after and 3 hours after 4 times were added to the reaction vessel in four batches for polymerization and then cooled to 80° C. to obtain an acrylic modified polyester resin solution. After 80 parts of triethylamine was added to the acrylic modified polyester resin solution to neutralize it, 3,400 parts of deionized water was added over 1 hour with vigorous stirring to give an acrylic modified polyester resin aqueous solution (solid content 20%). %) as an anchor layer coating liquid 4. The acid value of the polyester resin was 105 mgKOH/g.

(Examples 1 and 2)
Using a thermoplastic polycaprolactone-based urethane elastomer film (thickness 100 μm) as a base material, the anchor layer coating solution 1 is dried and adjusted so that the coating thickness is 0.3 μm, and the temperature is 100° C. A base material having anchor layers laminated was obtained by drying with air. Furthermore, after coating the components of the following silicone-based pressure-sensitive adhesive layer coating liquid on the anchor layer in an environment of 25° C. and 85% RH to a coating thickness of 30 μm (after drying), 120° C. and 150° C. in an oven. The silicone pressure-sensitive adhesive layer was laminated by crosslinking in seconds. A thermal transfer in which a transparent PET film having a thickness of 50 μm is attached as a separator film to the surface of the laminated silicone-based pressure-sensitive adhesive layer as a separator film, and the anchor layers of Examples 1 and 2 and the silicone-based pressure-sensitive adhesive layer are laminated. An image receiving film was obtained.
(Silicone adhesive layer coating liquid)
Linear polyorganosiloxane having vinyl groups only at both ends 68.3 parts (solventless type)/(Mw:80,000)
Organohydrogenpolysiloxane 0.7 parts (solventless type)/(Mw:2,000)
Platinum catalyst (trade name: PL-56, manufactured by Shin-Etsu Chemical Co., Ltd.) 1.0 part Toluene 30.0 parts

(Example 3 )
A thermal transfer image-receiving film of Example 2 was obtained in the same manner as in Example 1 except that a thermoplastic white polyester-based urethane elastomer film (Higres DUS202-CER7 manufactured by Seadam Co., Ltd., thickness 100 μm) was used as the substrate.

(Example 4 )
A thermal transfer image-receiving film of Example 3 was obtained in the same manner as in Example 1, except that the anchor layer coating liquid 3 was used as the anchor layer coating liquid.

(Comparative Example 1)
A thermal transfer image-receiving film of Comparative Example 1 was obtained in the same manner as in Example 1 except that the anchor layer coating liquid 2 was used as the anchor layer coating liquid.

(Comparative example 2)
A thermal transfer image-receiving film of Comparative Example 2 was obtained by the same method as in Example 1 except that the anchor layer coating liquid 4 was used as the anchor layer coating liquid.

(Comparative example 3)
A thermal transfer image-receiving film of Comparative Example 3 was obtained in the same manner as in Example 1 except that the anchor layer was not provided and the silicone-based adhesive layer coating liquid was directly applied.

(Hot-melt transfer recording medium 1)
(Release layer)
A 0.2 μm thick stick-preventing layer made of a silicone resin was formed on one surface of a polyethylene terephthalate film having a thickness of 5 μm, and a release layer coating solution having the following formulation was dried on the other surface to a thickness of 0.5 μm. Then, the coating was applied so that it was dried with hot air at 60° C. to form a release layer.
Polyethylene wax (melting point 80° C.) 16.0 parts Ethylene-vinyl acetate copolymer 4.0 parts Toluene 80.0 parts

(Color material-containing thermal adhesive layer)
A colorant-containing thermal adhesive layer coating liquid having the following formulation was applied on the release layer with a tube coater to a thickness of 1.2 μm, and dried with hot air at 60° C. to heat-melt. A mold transfer recording medium 1 was obtained.
Thermoplastic polyester resin (softening point 60° C.) 10.0 parts Carbon black 10.0 parts Methyl ethyl ketone 64.0 parts Butyl acetate 16.0 parts

(Thermal-fusion transfer recording medium 2)
(Color material-containing thermal adhesive layer)
A 5 μm thick polyethylene terephthalate film was coated with a 0.2 μm thick stick-preventing layer made of a silicone resin on one side, and the other side was dried with a coloring material-containing thermal adhesive layer coating solution to give a thickness after drying. It was coated so as to have a thickness of 2.0 μm and dried with hot air at 60° C. to obtain a heat-melt transfer recording medium 2.
Polyethylene wax (melting point 80° C.) 10.0 parts Carnauba wax (melting point 83° C.) 4.0 parts Ethylene-vinyl acetate copolymer 3.0 parts Carbon black 3.0 parts Toluene 80.0 parts

(Examples 1, 3, 4, Comparative Examples 1 to 3)
The thermal transfer image-receiving films of Examples 1, 3, 4, and Comparative Examples 1 to 3 and the heat-melting type transfer recording medium 1 were cut into a width of 12 mm and incorporated into a cassette for a tape printer used below, and a tape printer was used. The printing was evaluated under the following printing conditions 1. The results are shown in Table 1.

(Printing condition 1)
Tape Printer: King Jim Co., Ltd. Tepra Pro SR-330
Printing speed: Approx. 10 mm/sec
Printing pattern: Solid pattern, Checker flag pattern Printing atmosphere temperature: 23±2℃

(Example 2)
The thermal transfer image-receiving film of Example 2 and the thermal melting type transfer recording medium 2 were cut into 110 mm width, and the printing was evaluated under the following printing conditions 2 using a bar code printer. The results are shown in Table 1.

(Printing condition 2)
Bar code printer: Sato Co., Ltd. SG-408
Printing speed: 100mm/sec
Printing pattern: Solid pattern, Bar code pattern Printing atmosphere temperature: 23±2℃

(Printing Evaluation) Printing was performed under the printing conditions of each Example and Comparative Example, the printing result was visually observed, and the transferability was evaluated according to the following criteria.
◯: There are no missing prints or solid areas that cannot be transferred.
Δ: There is a small chip in the print or a portion that cannot be transferred, but there is no problem in practical use.
X: There is a print defect or a solid portion that cannot be transferred.

(Silicone residual property evaluation)
1. In each of the examples and comparative examples, a sample obtained by cutting a film coated with a silicone-based adhesive layer to a size of 50 mm×50 mm is prepared, and the silicone-based adhesive layer surface of each sample is attached to a transparent glass plate.
2. A light resistance test is performed by irradiating the glass surface with a carbon arc for 100 hours.
3. The film of the sample subjected to the light resistance test was peeled off by 180° peeling, and the silicone residue of the silicone-based pressure-sensitive adhesive layer on the glass was evaluated according to the following criteria.
◯: No silicone residue is generated.
Δ: Silicone residue partially occurs.
X: Silicone residue is generated on the entire surface.

(Water resistance evaluation of anchor layer)
1. In each of the examples and comparative examples, a sample obtained by cutting a film coated with a silicone-based adhesive layer to a size of 50 mm×50 mm is prepared, and the silicone- based adhesive layer surface of each sample is attached to a transparent glass plate.
2. The sample attached to the transparent glass plate is immersed in deionized water for 100 hours.
3. After completion of the immersion, the edge portion of the sample dried at room temperature was rubbed with a finger to evaluate the degree of peeling of the silicone-based pressure-sensitive adhesive layer according to the following criteria.
◯: No peeling occurred.
Δ: Partially peeled from the substrate.
X: Completely peeled off.

(Evaluation of curved surface followability)
The thermal transfer image-receiving films of Examples and Comparative Examples cut into a size of 1.50 mm×50 mm are prepared.
2. After peeling the separator film of the thermal transfer image-receiving film prepared in item 1, the silicone adhesive layer is attached to a smartphone having a curved surface at the end of the screen display surface. A thermal transfer image-receiving film is attached so that air bubbles do not enter between the silicone adhesive layer and the smartphone.
3. A jig made of styrofoam processed so as to fit the curved shape of the smartphone is prepared, and the thermal transfer image-receiving film that has been affixed is pressed against the smartphone with a force of 10 N for 60 seconds using this jig.
4. After releasing the pressing of the jig, 60 minutes later, it is confirmed whether the thermal transfer image receiving film is lifted on the curved surface of the smartphone.
Evaluation criteria ◯: No floating after 60 minutes.
Δ: After 60 minutes, a part of the curved surface part floats.
X: After 60 minutes, the entire curved surface part has been lifted up.

The above evaluation results are summarized in Table 1.

プリンターＡ：キングジム株式会社製 テプラ プロＳＲ−３３０
プリンターＢ：株式会社サトー製 ＳＧ−４０８

Printer A: Tepla Pro SR-330 manufactured by King Jim Co., Ltd.
Printer B: SG-408 manufactured by Sato Co., Ltd.

Claims (4)

Used for a printing method of performing thermal transfer recording on a film obtained by laminating a pressure-sensitive adhesive layer and a separator film on one surface of a polyurethane-based elastomer substrate in this order, and using a heat-melt transfer recording medium on the other surface of the substrate. in the thermal transfer image-receiving film to be made of a crosslinked product of an addition reaction type silicone resin pressure-sensitive adhesive layer is thermally crosslinked by hydrosilylation reaction between organohydrogenpolysiloxane having a polyorganosiloxane and SiH groups having a vinyl group, and A thermal transfer image-receiving film, wherein an anchor layer made of an acrylic modified polyester resin having an acid value of 7 to 100 mgKOH/g is provided between the base material and the pressure-sensitive adhesive layer. A thermal transfer recording method, wherein printing is performed on the thermal transfer image-receiving film according to claim 1, using a thermal fusion type transfer recording medium having at least a thermal adhesive layer on a substrate. The thermal transfer recording method according to claim 2, wherein the content ratio of the thermoplastic polyester resin in the thermal adhesive layer is 50 to 100% by weight. The thermal transfer recording method according to claim 2 or 3, wherein the thermal transfer image-receiving film is a tape-shaped member, and printing is performed by a tape printer that prints print data on the tape-shaped member. Recording method.