JPH05116467A - Image receiving sheet for sublimation transfer recording - Google Patents

Abstract

PURPOSE:To obtain an image receiving sheet which does not warp or curl by the heat of a thermal head when recording is performed by providing a dye receiving layer on a base material and providing a highly elastic resin layer with at least a specified elasticity and at most a specified thickness on the opposite side of the dye receiving layer of the base material. CONSTITUTION:A dye receiving layer 2 consisting of a polyester resin etc., is provided on a base material 1 and a highly elastic resin layer 3 with an elasticity of at least 150 kgf/mm<2> and a thichness of at most 60mum and consisting of polyethylene terephthalate is provided on the opposite side of the dye receiving layer 2 of the base material 1. As the result, an image receiving sheet for sublimation transfer recording which does not warp or curl by the heat of a thermal head when recording is performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image receiving sheet used in a sublimation type thermal transfer recording system.

[0002]

2. Description of the Related Art The sublimation type thermal transfer recording system is characterized in that the sound is quiet, the apparatus is small and inexpensive, the maintenance is easy, and the output time is short. Since it is used, it is possible to easily perform high-gradation recording by continuously changing the amount of heat generation energy, and it has characteristics such as high density and high resolution. Therefore, it is particularly advantageous in obtaining a full-color hard copy as compared with other recording systems, and is widely adopted as a recording system for color printers, video printers, and the like.

Conventionally, as a recording medium of this recording system,
As disclosed in U.S. Pat. No. 4,778,782, a material in which a dye receiving layer is formed on a substrate made of plain paper or synthetic paper (mainly polypropylene paper) has been used.

In order to use the image-receiving sheet recorded by the sublimation type thermal transfer recording system in an overhead projector, it is proposed to provide a dye receiving layer on a transparent resin film substrate such as polyethylene terephthalate film. ing.

However, these image-receiving sheets have a problem that the image-receiving sheet is warped or curled due to the heat of the thermal head during recording.

[0006]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to obtain an image receiving sheet which does not warp or curl during recording.

[0007]

[Means for Solving the Problems] The problem is that a dye receiving layer is provided on a substrate, and the elastic modulus is 150 kgf / mm ² or more and the thickness is 60 μm or less on the opposite side of the substrate from the dye receiving layer. It is solved by providing the high elastic resin layer.

The present invention will be described in detail below. Figure 1
Shows an example of the image-receiving sheet of the present invention. In the figure, reference numeral 1 is a base material. The dye receiving layer 2 is provided on one surface of the base material 1, and the high-elasticity resin layer 3 is provided on the other surface of the base material 1 to form the image receiving sheet of this example.

The substrate 1 serves as a substrate of the image receiving sheet, and cellulose fiber paper, synthetic paper, plastic film or the like is used. As cellulose fiber paper, fine paper,
Examples include art paper, coated paper, cast coated paper, synthetic rubber latex-impregnated paper, synthetic resin emulsion-impregnated paper, and the like.

As the synthetic paper, a polyolefin resin or other synthetic resin is used as a resin component, and an inorganic filler or the like is added to and mixed with the resin component, and extruded into a film or sheet, or polystyrene or polyester. ,
Examples thereof include resin films such as polyolefins and those produced by applying an extender pigment on the surface of a sheet.

As the plastic film, polyolefin such as polyethylene or polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyvinyl alcohol, acrylic resin, cellulose resin, ethylene vinyl acetate copolymer, ethylene vinyl alcohol copolymer Coalesced, ionomer, polyester,
Various plastic films such as aliphatic polyamide, aromatic polyamide, polycarbonate, polyarylate, polyether sulfone, polyether ether ketone, polyether imide, and polyimide are mentioned, and a film is formed by adding a filler to these films. A white film or a foamed film having fine foaming can also be used.

The base material 1 may be the above-mentioned various base materials alone,
It may be a composite base material in which two or more base materials are bonded together as required. Further, it is possible to use a base material which has been subjected to various treatments such as a conductive treatment and an easy-adhesion treatment in consideration of dustproofness, running property, adhesion and the like. Further, when the substrate 1 is made of a highly transparent material, an image receiving sheet suitable for OHP can be obtained. The thickness of the substrate 1 is usually 200 μm or less, preferably 70 to 150 μm.

Further, the dye receiving layer 2 is a layer that develops a color by receiving a sublimable dye that migrates from the transfer sheet, and the material forming the dye receiving layer 2 is not particularly limited, and for example, Polyester resin, polyacrylic ester resin, polycarbonate resin, polyvinyl acetate resin, styrene acrylate resin, vinyl toluene acrylate resin and other ester bond resins, polyurethane resin and other urethane bond resin, polyamide resin (nylon), etc. Resins having a highly polar bond such as amide bond and urea bond such as urea resin, polycaprolactone resin, styrene resin, polyvinyl chloride resin, vinyl chloride-vinyl acetate copolymer, polyacrylonitrile resin, and the like. It is also possible to use a mixture or copolymer of the above. Further, those obtained by containing an inorganic filler such as silica, calcium carbonate, titanium oxide or zinc oxide in these synthetic resins or cross-linked with a thermosetting cross-linking agent such as amino-modified silicone and epoxy-modified silicone or isocyanate and polyol are also used. be able to.

However, as a material constituting the dye receiving layer 2, a composition containing a sublimable disperse dye receiving resin (hereinafter sometimes referred to as a dyeing resin) and a crosslinking agent curable with active energy rays is used. From the viewpoint of productivity and performance, it is preferable to use one that is applied onto the base material 1 and then cured with an active energy ray. Specifically, a release agent is added to 100 parts by weight of a mixture consisting of 40 to 95% by weight of a polyester resin as a sublimable disperse dye-accepting resin and 60 to 5% by weight of a crosslinking agent curable by an active energy ray. A composition obtained by curing a composition prepared by mixing 01 to 30 parts by weight is used.
The dye receiving layer 2 made of these compositions easily dyes a sublimable disperse dye, is excellent in stability, and has very good gloss retention after recording.

As the polyester resin, a linear thermoplastic polyester resin obtained by polycondensation of a dicarboxylic acid and a diol and / or a polycondensation of an unsaturated polybasic acid having a reactive double bond with a polyhydric alcohol is used. The obtained unsaturated polyester resin may, for example, be mentioned. Among them, a molecular weight of 2000 to 4000 obtained by polycondensation of at least one dicarboxylic acid and at least one diol.
A linear thermoplastic polyester resin having a degree of crystallinity of 0 and a crystallinity of 1% or less is preferable in terms of solubility in an organic solvent, easiness of dyeing, and good light resistance.

The blending amount of the polyester resin is preferably 40 to 95% by weight of the total amount with the crosslinking agent. If it is less than 40% by weight, the dyeing density by the sublimable disperse dye does not become dark under low energy conditions. If the blending amount of the polyester resin exceeds 95% by weight, the amount of the cross-linking agent decreases, and the blocking resistance with the color sheet (transfer paper) coated with the sublimable disperse dye becomes poor, and the sublimable disperse dye easily dyeable resin. The article coated with the composition and cured with active energy rays and the color sheet will cause blocking (sticking) during thermal transfer. More preferably 55% by weight
It is in the range of 94% by weight.

Specific examples of the linear thermoplastic polyester resin obtained by polycondensation of at least one dicarboxylic acid and at least one diol include terephthalic acid / isophthalic acid / ethylene glycol / neopentyl glycol. Polyester resin, other terephthalic acid / isophthalic acid / ethylene glycol / bisphenol A-ethylene oxide adduct, terephthalic acid / isophthalic acid / ethylene glycol / 1,6-hexanediol, terephthalic acid / isophthalic acid / sebacic acid / ethylene glycol / neo Polyethylene obtained from pentyl glycol, terephthalic acid / sebacic acid / ethylene glycol / neopentyl glycol, terephthalic acid / isophthalic acid / adipic acid / ethylene glycol / neopentyl glycol Can be mentioned ether resin, 2
It is also possible to use a combination of two or more species. In particular, from the viewpoint of stability against light, heat, water, etc., it is preferable to use two or more of these polyesters in combination in order to improve the stability. For example, when two kinds of polymers A and B are used in combination, the preferable range of use of the polymer is that A is 20
˜80 wt%, B is 80 to 20 wt%.

It is naturally possible to use esterified dimethyl terephthalate, dimethyl isophthalate or the like instead of terephthalic acid or isophthalic acid as a raw material for condensation polymerization.

The unsaturated polyester resin obtained by polycondensation of an unsaturated polybasic acid having a reactive double bond and a polyhydric alcohol includes maleic anhydride / phthalic anhydride / propylene glycol and maleic anhydride / Isophthalic acid / Propylene glycol, Maleic acid / Fumaric acid /
Isophthalic acid / 1,3-butanediol, maleic acid /
Examples thereof include resins obtained from isophthalic acid / neopentyl glycol, maleic anhydride / tetrahydrophthalic anhydride / dipropylene glycol, and the like.

The cross-linking agent is blended in order to cure the resin composition constituting the dye receiving layer with active energy rays and to impart sufficient blocking resistance to the dye receiving layer. 5 to 60% by weight of the total amount,
It is preferably in the range of 6 to 45% by weight. This is because if the compounding amount of the cross-linking agent is less than 5% by weight, blocking is likely to occur, while if it exceeds 60% by weight, the ratio of the dyeing resin is reduced and a sufficient dyeing density cannot be obtained. is there.

The crosslinking agent used in the present invention preferably has at least one kind of polyfunctional monomer in consideration of the curing of the resin composition and the blocking resistance of the recording medium, and the active energy. When ultraviolet rays are used as the rays, monomers having an acryloyloxy group or a methacryloyloxy group as the polymerizable group of the crosslinking agent are preferred.

As the monomer having a (meth) acryloyloxy group, a polyether acrylate or polyether methacrylate type (hereinafter, "acrylate or metal relate" is simply abbreviated as "(meth) acrylate"), polyester (meth). Acrylate-based, polyol (meth) acrylate-based, epoxy (meth) acrylate-based, amidourethane (meth) acrylate-based, urethane (meth) acrylate-based, spiroacetal (meth) acrylate-based, urethane (meth)
Examples thereof include acrylate-based, spiroacetal (meth) acrylate-based, polybutadiene (meth) acrylate-based monomers and oligomers. Specific examples of such monomers and oligomers include 1,2,6-
Hexanetriol / propylene oxide / acrylic acid, polyether (meth) acrylate synthesized from trimethylolpropane / propylene oxide / acrylic acid; adipic acid / 1,6-hexanediol / acrylic acid, succinic acid / trimethylolethane / acrylic Polyester (meth) acrylate synthesized from acid; triethylene glycol diacrylate, hexapropylene glycol diacrylate, neopentyl glycol diacrylate, 1,4-butanediol dimethacrylate, 2-ethylhexyl acrylate, tetrahydrofurfuryl acrylate, 2- Hydroxyethyl methacrylate, ethyl carbitol acrylate, trimethylolpropane triacrylate, pentaerythritol tetraacrylate (Meth) acrylate or polyol such as dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, 2,2-bis (4-acryloyloxydiethoxyphenyl) propane, 2,2-bis (4-acryloyloxypropoxyphenyl) propane (Meth) acrylate; diglycidyl etherified bisphenol A / acrylic acid,
Epoxy (meth) acrylates such as diglycidyl etherified polybisphenol A / acrylic acid, triglycidyl etherified glycerin / acrylic acid; γ-butyrolactone / N-methylethanolamine / bis (4-isocyanatocyclohexyl) methane / 2-hydroxy Amidourethane (meth) acrylates such as ethyl acrylate, γ-butyrolactone / N-methylethanolamine / 2,6-tolylene diisocyanate / tetraethylene glycol / 2-hydroxyethyl acrylate;
Urethane acrylates such as 2,6-tolylene diisocyanate diacrylate, isophorone diisocyanate diacrylate, and hexamethylene diisocyanate diacrylate, diarylidene pentaerythritol / 2-
Examples thereof include spiro acetal acrylate synthesized from hydroxyethyl acrylate; acrylated polybutadiene synthesized from epoxidized butadiene / 2-hydroxyethyl acrylate, and the like. These monomers and oligomers are used alone or as a mixed system of two or more kinds.

In the present invention, a monomer or oligomer as a particularly preferable crosslinking agent is represented by the following general formula (1)

[0024]

[Chemical 1]

(In the formula, m1 is an integer of 1 to 4, and at least three X are represented by the general formula: CH ₂ = CH-COO-R ₁
-(In the formula, R ₁ represents a single bond, an alkylene group having 1 to 8 carbon atoms or a polyoxyalkylene group having an alkylene group having 1 to 8 carbon atoms),
The remainder is an alkyl group having 1 to 8 carbon atoms, a hydroxyl group, an amino group, a formula: — (OR ₂ ) _{m 2} —H (In the formula, R ₂ has 1 carbon atom.
~ 8 represents an alkylene group, m2 is a positive integer. )
A group represented by the formula: — (OR ₂ ) _{m 2} —OH (in the formula, R ₂ represents an alkylene group having 1 to 8 carbon atoms, and m 2 is a positive integer), or a group represented by the formula: :-( OOCR
₂₎ in _{m @ 2} -H (wherein, R ₂ represents an alkylene group having 1 to 8 carbon atoms, _m2 represents a group represented by a positive integer.). ), For example, dipentaerythritol tetraacrylate, dipentaerythritol pentaacrylate, dipentaerythritol hexaacrylate, tripentaerythritol pentaacrylate,
Tripentaerythritol hexaacetylate, tripentaerythritol heptaacrylate, etc., or the following general formula (2)

[0026]

[Chemical 2]

[0027] (wherein, m3 is from 1 to 10 a positive integer, X is optionally -OH is -OCOCH = CH _2.) Poly bisphenol A polyacrylates represented by, for example, diglycidyl ethers of bisphenol A diacrylate of A, Epicoat # 1001 (manufactured by Shell: m3 =
Diacrylate of 3) or the following general formula (3)

[0028]

[Chemical 3]

(In the formula, X ₁ , X ₂ , ..., X _m4 have 6 carbon atoms.
The same or different alkylene groups below or one of which has a structure in which one hydrogen atom is substituted with a hydroxyl group,
m4 is an integer of 0-5. ), For example, 2,2-bis (4-acryloyloxydiethoxyphenyl) propane, 2,2-bis (4-acryloyloxytriethoxyphenyl) propane, 2,2-bis (4-acryloyloxydi) Propoxyphenyl) propane, etc., and especially when ultraviolet rays are used as the active energy rays, they have very good quick-drying in air,
It is a particularly preferred crosslinking agent.

Further, in the present invention, in order to further improve the blocking resistance (sticking resistance) between the recording medium and the transfer sheet, it is preferable to incorporate a release agent in the dye receiving layer. Examples of the release agent used include silicon-based surfactants, fluorine-based surfactants, graft polymers having polyorganosiloxane as a trunk or branch, and compounds capable of having a silicon-based or fluorine-containing crosslinked structure. These release agents can be used alone or in combination. The compounding amount of the release agent is 0.01 to 3 relative to 100 parts by weight of the total amount of the dyeing resin and the crosslinking agent.
The amount is 0 parts by weight, preferably 0.05 to 10 parts by weight.

As the silicon-based surfactant, a compound in which polydimethylsiloxane and polyoxyalkylene are blocked (may be slightly modified with other functional groups) is effective, and CH ₃ — (SiO) 1 / 2-group and -O
Ratio of R-group (R: alkylene residue) is 1/10 to 1 /
0.1, preferably 1/5 to 1 / 0.2, is effective in improving blocking resistance, leveling property and dyeing density.

Specific examples of such a silicon-based surfactant include compounds represented by the following general formulas (4) and (6).

[0033]

[Chemical 4]

(Where P is the following general formula (5)

[0035]

[Chemical 5]

Where n1 and n2 are positive integers, x and y are 0 or positive integers, and the formula: 1/10
Satisfies ≦ (2n1 + 1) / (n2x + n2y) ≦ 10. R ₃ represents hydrogen, an alkyl group, an acyl group or an aryl group. )

[0037]

[Chemical 6]

(Where Q is the following general formula (7)

[0039]

[Chemical 7]

Where n3 and n4 are positive integers, x and y are 0 or positive integers, and the formula: 1/10
Satisfies ≦ (2n3 + n4 + 1) / (n4x + n4y) ≦ 10. z is 0 or an integer of 1 to 5. Also, R
₄ -Si (CH _{3) 3,} represent hydrogen, an alkyl group, an acyl group or an aryl group, R ₅ represents hydrogen, an alkyl group, an acyl group or an aryl group. )

As the fluorine-based surfactant, any nonionic, anionic, cationic or amphoteric system may be used as long as it is soluble in a mixture of a dyeing resin and a crosslinking agent and exhibits blocking resistance. 1 fluorinated surfactant
More than one species can be used. Of these, nonionic surfactants are preferable in view of improving the leveling property and blocking resistance of the recording medium.

Specific examples of the fluorochemical surfactant used in the present invention include, for example, fluoroalkoxypolyfluoroalkyl sulfates, anionic surfactants such as fluorocarbon sulfonates and fluorocarbon carboxylates, and N-fluoroalkyl. Sulfonamide alkylamine quaternary ammonium salt, N-fluoroalkylsulfonamide alkylamine salt, N-fluoroalkylamide alkylamine quaternary ammonium salt, N-fluoroalkylamide alkylamine salt, N-fluoroalkylsulfonamide alkylhalomethyl ether Cationic surfactants such as quaternary ammonium salts, fluorocarbon sulfonamides, fluorocarbon amino sulfonamides, fluorocarbon carboxy sulfonamides, fluorocarbons Hydroxysulfonamide, fluorocarbon sulfonamide ethylene oxide adduct, fluorocarbon hydroxysulfonamide sulfuric acid ester, fluorocarbon amino acid amide, fluorocarbon acid amide, fluorocarbon hydroxyacid amide, ethylene oxide addition condensate of fluorocarbon acid amide, fluorocarbon hydroxyacid amide sulfuric acid ester, fluorocarbon Sulfonic acid, fluorohydrocarbon carboxylic acid, fluorohydrocarbon alkyl ester, fluorohydrocarbon alkyl ether, fluorohydrocarbon carboxyalkyl ester, fluorohydrocarbon hydroxyamide,
Examples thereof include nonionic surfactants such as fluorohydrocarbon alkyl ester sulfuric acid and fluoroalkyldiamine, and amphoteric surfactants such as alkylamine having a betaine-type fluorocarbon sulfonamide bond and alkylamine having a betaine-type fluorocarbon acid amide bond.

As the graft polymer having a polyorganosiloxane as a trunk or a branch, a graft polymer having a polymer or a copolymer obtained by vinyl polymerization, polycondensation, ring-opening polymerization or the like as a trunk and a polyorganosiloxane as a branch is first used. Can be mentioned. Examples of these graft polymers include methacryloyloxy groups at one end,
Alkyl (meth) acrylate, (meth) acrylic acid, a derivative of (meth) acrylic acid having a functional group, vinyl acetate, vinyl chloride, (meth) acrylonitrile to polysiloxane (macromonomer) to which vinyl group or mercapto group is added , At least one of the monomers such as styrene
A graft polymer obtained by polymerizing a seed, a graft polymer obtained by reacting a dicarboxylic acid and a diol with a macromonomer having two hydroxyl groups or carboxyl groups near the end of polysiloxane, and two graft polymers near the end of polysiloxane. Examples thereof include graft polymers obtained by reacting a macromonomer having a hydroxyl group or a carboxyl group with a diepoxy or diisocyanate compound.

Examples of other graft polymers include graft polymers having a polyorganosiloxane as a backbone and a polymer or copolymer obtained by vinyl polymerization, polycondensation, ring-opening polymerization or the like as a branch. Examples of these graft polymers include organosilanes and silanes having a vinyl polymerizable group, such as 3-methacryloxypropyldimethoxymethylsilane, methylvinyldimethoxysilane, and ethylvinyldiethoxysilane, which are condensed to form side chains with methacryloyl. A polysiloxane having an oxy group is synthesized, and then the monomer and alkyl (meth) acrylate, (meth) acrylic acid, a derivative of (meth) acrylic acid having a functional group, vinyl acetate,
Graft polymer obtained by polymerizing at least one kind of monomer such as vinyl chloride, (meth) acrylonitrile and styrene, and glycidyl on a side chain by condensing organosilane and diethoxy-3-glycidoxypropylmethylsilane A graft polymer obtained by synthesizing a polysiloxane having a group, and then reacting this with (meth) acrylic acid to obtain a monomer containing a (meth) acryloyloxy group, and then polymerizing the monomer. , A graft polymer obtained by synthesizing a polysiloxane having a hydroxyl group in a side chain by condensing an organosilane and hydroxyethylmethyldimethoxysilane and then polycondensing a dicarboxylic acid and the diol.

When synthesizing the polysiloxane which becomes the trunk or branch of the graft polymer, a cyclic silane, particularly a cyclic dimethylpolysiloxane having 3 to 8 repeating units is used as a main raw material, and trimethylmethoxysilane or trimethylethoxysilane is used as a molecular weight adjusting agent. For example, a silane compound having one alkoxy group in one molecule may be used to perform polymerization at 70 to 150 ° C. using a functional group-containing silane and a strong acid or strong base as a catalyst.

By blending these graft polymers in the dye receiving layer, the blocking resistance with the transfer sheet is improved and the dark fading property of the dyed dye receiving layer is also improved. The blending amount thereof is preferably 0.01 to 30 parts by weight, and more preferably 0.05 to 10 parts by weight, based on 100 parts by weight of the mixture of the dyeing resin and the crosslinking agent. This is because if the blending amount is less than 0.01 part by weight, the improvement in blocking resistance is lessened and the dark fading property is not improved. On the contrary, if the blending amount exceeds 30 parts by weight, the dye receiving layer cured by active energy rays is This is because the dyeing density decreases as the milk becomes white.

The graft polymer containing polyorganosiloxane has a molecular weight of 1000 from the viewpoint of dark fading.
The above is preferable. Further, the weight ratio of the polyorganosiloxane component and the polymer or copolymer other than polyorganosiloxane is preferably polyorganosiloxane component / polymer or copolymer = 95/5 to 10/90, and more preferably Preferably 90/10 to 20/80
The range is. If this ratio exceeds 95/5, the dark fading property tends to become poor, and conversely, if it is less than 10/90, the dark fading property tends to become poor as well as the blocking resistance decreases.

As a thermal crosslinking type or active energy ray crosslinking type releasing agent capable of forming a silicon type or fluorine-containing type crosslinking structure, in a silicon type, a silicon type compound which causes an addition reaction and a silicon type compound which causes a radical reaction are used. ,
Examples include silicon compounds that cause a condensation reaction.
Examples of the silicon compound that causes the addition reaction include a combination of a silicone having a vinyl group and a silicone having a —SiH group, a combination of an amino-modified silicone and an epoxy-modified silicone, and if necessary, a catalyst such as a platinum compound may be used. You may use together. As a silicon compound that causes a radical reaction, there is a combination of a silicone having a vinyl group and a silicone having a methylsilane.
An organic peroxide may be used as a polymerization initiator. Examples of the silicone compound that causes a condensation reaction include a silicone having an alkoxy group, a silicone having a silanol group, a combination of a silicone having an alkoxy group and a silicone having a silanol group, a silicone having a silanol group and a silicone having a -SiH group. And a combination of a silicone having a silanol group and a silicone having an aminooxy group.

In the fluorine-containing system, a combination of an epoxy group-containing fluorine-containing compound and an amino group-containing fluorine-containing compound as a fluorine-containing compound that causes an addition reaction, and a carboxylic acid group-containing fluorine-containing compound as a condensation-containing fluorine-containing compound And a fluorine-containing compound containing an amino group.

In order for these silicon-based or fluorine-containing compounds to form a sufficient crosslinked structure, it is necessary to have at least more than 2 functional groups per molecule of the compound, and 2 or less functional groups per molecule. However, even if a high molecular weight substance is formed, a sufficient crosslinked structure cannot be obtained.

Examples of the active energy ray-crosslinking type silicon-based or fluorine-containing compounds include radically polymerizable compounds such as vinyl group, allyl group, methacryloyl group and acryloalkyl group. When ultraviolet rays are used as the active energy rays, a compound having an acryloyloxy group, which has good polymerizability by ultraviolet rays, is preferable. In order for these active energy ray crosslinkable compounds to have a sufficient crosslinked structure, it is necessary to have at least one polymerizable group per molecule.

In the present invention, when an active energy ray-crosslinking type releasing agent is used, the releasing agent should be cured at the same time when the resin composition constituting the dye receiving layer is cured with active energy rays. However, when a heat-crosslinking release agent is used, it is necessary to add a heat-curing step in addition to the curing of the resin composition. Therefore, from the viewpoint of productivity, it is preferable to use the active energy ray-crosslinking type release agent.

When a monomer such as tetrahydrofurfuryl acrylate having a high polymer solubility and a low viscosity is used as a crosslinking agent in the production of the recording medium of the present invention, roll coating, bar coating, It is possible to form the dye receiving layer by coating the resin composition on the surface of the substrate by coating such as blade coating. However, in order to improve the workability of coating work, a solvent such as ethyl alcohol, methyl ethyl ketone, toluene, ethyl acetate, dimethylformamide, etc. was added to the resin composition to adjust the coating viscosity to an appropriate level. Is preferred. Thereby, spray coating, curtain coating, flow coating, dip coating and the like can be easily performed.

In the present invention, active energy rays such as electron beams and ultraviolet rays are used to cure the resin composition constituting the dye receiving layer, but ultraviolet rays are used in consideration of the control of the radiation source. Is preferred. When ultraviolet rays are used as the active energy rays, the photopolymerization initiator is added in an amount of 0.1 to 1 with respect to 100 parts by weight of the mixture of the dyeing resin and the crosslinking agent.
Add 0 parts by weight.

The photopolymerization initiator used is benzoin, benzoin isobutyl ether, benzyl dimethyl ketal, ethylphenyl glyoxylate, diethoxyacetophenone, 1,1-dichloroacetophenone, 4'-isopropyl-2-hydroxy-2. -Methyl propiophenone, 1-hydroxycyclohexyl phenyl ketone, benzophenone, benzophenone / diethanolamine, 4,4'-bisdimethylaminobenzophenone, 2-methylthioxanthone, tert-butylanthraquinone, carbonyl compounds such as benzyl, tetramethylthiuram monosulfide , Sulfur compounds such as tetramethylthiuram disulfide, azo compounds such as azobisisobutyronitrile and azobis-2,4-dimethylvaleronitrile Benzoyl peroxide, di -
Peroxide compounds such as tert-butyl peroxide may be mentioned. These compounds can be used alone or in combination of two or more kinds.

Further, in the present invention, depending on the purpose, the dye receiving layer may be blended with fine inorganic particles such as silica, alumina, talc, titanium oxide or the like having a size of several μm or less.
The recording medium of the present invention can be produced by coating the surface of a substrate with the above resin composition and irradiating with active energy rays. The thickness of the dye receiving layer is preferably 1 μm or more, and
If it is less than μm, the dyeing density and stability are insufficient.

The high elastic resin layer 3 is for preventing the image receiving sheet from warping during recording, and has an elastic modulus of 150 kg.
It is made of resin of f / mm ² or more, and its thickness is 60 μm or less,
It is preferably 5 to 60 μm. The elastic modulus referred to here is a sample width of 5 mm, a chuck width of 20 mm, and a pulling speed of 20 mm /
It is the tensile elastic modulus measured under the condition of minutes.

The resin having the above elastic modulus may be a thermoplastic resin or a curable resin, and the curable resin may be a thermosetting resin or a curable resin such as an ultraviolet ray or an electron beam. Those that do are also used.

Specific examples of the thermoplastic resin include polyethylene terephthalate, cellulose triacetate, (meth) acrylic resin and the like. Examples of the heat-curable resin include epoxy resin, polyimide, unsaturated polyester and the like, and UV-curable resin. Examples of the resin include (meth) acrylic resin. An image-receiving sheet suitable for OHP can be obtained by forming a high-elasticity resin layer 3 using a transparent base material as the base material 1 using a resin having good transparency among these resins.

A coating method or a laminating method is used for forming the high-elasticity resin layer 3. When using a thermoplastic resin, create an extruded film of this in advance,
For example, a method of laminating this on the substrate 1 or a method of coating a resin solution dissolved in a solvent, and when a curable resin is used, an ordinary method of coating an uncured liquid material and curing it Is used.

The high elastic resin layer 3 has an elastic modulus of 150 kg.
It is indispensable that the resin is f / mm ² or more.
If it is less than kgf / mm ² , sufficient warp prevention effect cannot be obtained. When the high-elasticity resin layer 3 is composed of a stretched film, the elastic modulus of the film in both MD and TD needs to be 150 kgf / mm ² or more. If the elastic modulus in either direction is less than 150 kgf / mm ² , warpage is likely to occur in that direction. The high elastic resin layer 3 has an elastic modulus of 150 kg.
Various additives, fillers and the like may be contained within a range not lower than f / mm ² .

The high-elasticity resin layer 3 has a thickness of 60 μm.
Must be: When the thickness exceeds 60 μm, the image receiving sheet obtained becomes thick and may not be conveyed depending on the printer. Further, in order to obtain a sufficient warp prevention effect, the thickness of the high elastic resin layer 3 is preferably 5 μm or more. The high elastic resin layer 3 has an elastic modulus of 3
When it is at least 00 kgf / mm ^2, it is more preferable because a sufficient warp prevention effect can be obtained even if the thickness of the high-elasticity resin layer 3 is thinner.

In the image receiving sheet having such a structure,
Even after receiving heat from the thermal head during recording, the presence of the high-elasticity resin layer 3 prevents the image-receiving sheet from warping or curling. That is, it is assumed that the heat of the thermal head causes the image-receiving layer side of the image-receiving sheet to be thermally shrunk, and the force of warping in a concave shape is suppressed by the rigidity of the high-elasticity resin layer 3 on the opposite side, thereby reducing the warpage. ..

FIG. 2 shows another example of the image-receiving sheet of the present invention. In this example, the intermediate layer 4 is interposed between the substrate 1 and the dye-receiving layer 2. This middle layer 4
Is for absorbing the impact of the thermal head during recording, and is made of saturated polyester, polyurethane, polyacrylic acid ester, or the like.

The intermediate layer 4 preferably has a thickness of about 3 to 15 μm and a uniform thickness, and the thickness variation is preferably ± 10% or less, more preferably ± 5% or less. .. Examples of the method for forming the intermediate layer 4 include reverse roll coating, clavia coating, wire bar coating and the like. By providing the intermediate layer 4, the variation in the thickness of the dye receiving layer 2 is absorbed, and the clarity of the recorded image is improved.

Hereinafter, examples of the present invention will be described in more detail.

Example 1 A milky white polyester film (W made by DIAFOIL) on one surface of coated paper (thickness: 85 μm)
-300, thickness 38 μm) was laminated. Toyo Morton AD-577-1 and CAT-52 were used as the adhesive, and the coating amount was set to 5 g / m ^{2 when} dry. Drying was performed at 80 ° C. for about 30 seconds and aged at 40 ° C. for 2 days.

The composition shown in Table 1 was mixed with the milk-white polyester film W-300 surface of the obtained substrate, and after preparation,
The solution was applied uniformly by a dipping method, and further irradiated with ultraviolet rays from a high pressure mercury lamp in air to form a dye receiving layer having a film thickness of 5 to 6 μm. Then, on the other surface of the substrate, a methyl ethyl ketone solution (2) of acrylic resin BR-80 manufactured by Mitsubishi Rayon Co., Ltd.
0 wt%) was applied using a wire bar and dried to form a 10 μm thick highly elastic resin layer to prepare an image receiving sheet. The elastic modulus of the high elastic resin layer alone measured by the above method was 180 kgf / mm ² .

[0069]

[Table 1]

The abbreviations in Table 1 are as follows. * 1) 2P6A: dipentaerythritol hexaacrylate * 2) 2P5A: dipentaerythritol pentaacrylate * 3) 2P4A: dipentaerythritol tetraacrylate * 4) A-DEP: 2,2-bis (4-acryloyloxydiethoxyphenyl) ) Propane * 5) Polyester resin A: Polyester resin obtained by condensation polymerization of terephthalic acid / isophthalic acid / sebacic acid / ethylene glycol / neopentyl glycol (molecular weight 20000-25000, glass transition temperature 10 ° C) * 6) Polyester resin B : Polyester resin (molecular weight 20000 to 2500) polymerized by condensation polymerization of terephthalic acid / isophthalic acid / sebacic acid / ethylene glycol / neopentyl glycol / 1,4-butanediol
0, glass transition temperature 47 ° C.) * 7) Silicon-based surfactant A: a silicon-based surfactant represented by the following general formula, in which n3, n4, and x are:
Formula: (2n3 + n4 + 1) / (n4x) = 1.3 is satisfied.

[0071]

[Chemical 8]

Example 2 A milky white polyester film (W made from dia foil) on one side of coated paper (thickness: 85 μm)
-300, thickness 38 μm) and laminated on the other side with a milky white polyester film W400 (manufactured by DIAFOIL,
Thickness 38 [mu] m, elastic modulus MD direction 235kgf / mm ^2, the TD direction 255kgf / mm ²⁾ was laminated. Toyo Morton AD-577-1 and CAT-52 were used as the adhesive, and the coating amount was 3 g / m ^{2 when} both were dry. Drying was performed at 80 ° C. for about 30 seconds and aged at 40 ° C. for 2 days.

The composition shown in Table 1 was mixed with the milk-white polyester film W-300 surface of the obtained substrate, and after preparation,
The solution was applied uniformly by a dipping method, and further irradiated with ultraviolet rays from a high pressure mercury lamp in air to obtain an image receiving sheet having a dye receiving layer with a film thickness of 5 to 6 μm.

(Example 3) A milky white polyester film (W made by DIAFOIL) on one side of coated paper (thickness: 85 μm)
-300, thickness 38 μm) and laminated on the other side with a milky white polyester film W900 (manufactured by DIAFOIL,
Thickness 38 [mu] m, elastic modulus MD direction 190kgf / mm ^2, the TD direction 175 kgf / mm ²⁾ was laminated. Toyo Morton AD-577-1 and CAT-52 were used as the adhesive, and the coating amount was 3 g / m ^{2 when} both were dry. Drying was performed at 80 ° C. for about 30 seconds and aged at 40 ° C. for 2 days.

The composition shown in Table 1 was mixed with the milk-white polyester film W-300 surface of the obtained substrate, and after preparation,
The solution was applied uniformly by a dipping method, and further irradiated with ultraviolet rays from a high pressure mercury lamp in air to obtain an image receiving sheet having a dye receiving layer with a film thickness of 5 to 6 μm.

Comparative Example 1 An image receiving sheet was prepared in the same manner as in Example 1, except that the high elastic resin layer was not formed.

(Comparative Example 2) A milky white polyester film (made by Diafoil W on one side of coated paper (thickness: 85 μm))
-300, thickness 38 [mu] m) was laminated on the opposite side synthetic paper Yupo FPG (Oji-Yuka Synthetic Paper Co., Ltd., thickness 60 [mu] m, elastic modulus MD direction 70 kgf / mm ^2, TD direction 140 kgf / mm ²⁾
Was laminated. Adhesive is Toyo Morton AD-57
7-1 and CAT-52 were used, and the coating amounts were both dry and 3 g / m ² . Drying was performed at 80 ° C. for about 30 seconds and aged at 40 ° C. for 2 days.

The composition shown in Table 1 was mixed with the milk-white polyester film W-300 surface of the obtained substrate, and after preparation,
The solution was applied uniformly by a dipping method, and further irradiated with ultraviolet rays from a high pressure mercury lamp in air to obtain an image receiving sheet having a dye receiving layer with a film thickness of 5 to 6 μm.

(Comparative Example 3) A milky white polyester film (Diafoil W) on one surface of coated paper (thickness: 85 μm)
-300, thickness 38μm) and polypropylene film Toyopearl SS P-4256 on the other side.
(Manufactured by Toyobo, thickness 50 μm, elastic modulus horizontal direction 110 kgf / mm
² and 70 kgf / mm ^{2 in the} longitudinal direction were laminated. Toyo Morton AD-577-1 and CAT-52 were used as the adhesive, and the coating amount was 3 g / m ^{2 when} both were dry.
Drying was performed at 80 ° C. for about 30 seconds and aged at 40 ° C. for 2 days.

The composition shown in Table 1 was mixed and prepared on the milk-white polyester film W-300 surface of the obtained substrate,
The solution was applied uniformly by a dipping method, and further irradiated with ultraviolet rays from a high pressure mercury lamp in air to obtain an image receiving sheet having a dye receiving layer with a film thickness of 5 to 6 μm.

The transfer layer of the thermal transfer sheet (Mitsubishi SCT-CK100S) is faced to the dye receiving layer of the image receiving sheet thus obtained, and the thermal transfer printer (Mitsubishi SCT
In CT-CP100), an image was formed by heating from the back side of the thermal transfer sheet with a thermal head, and the image receiving sheets of Examples 1, 2, and 3 all had a warp of 3 mm or less, but Comparative Example 1, 8 mm for a few image receiving sheets
That was all. (However, the warp value is shown as the average value of the warped heights of the four corners of the image receiving sheet.)

Example 4 A transparent polyethylene terephthalate film having a thickness of 25 μm (elastic modulus MD) is formed on one side of a transparent polyethylene terephthalate film having a thickness of 100 μm.
Direction 220kgf / mm ^2, TD direction 220 kgf / mm ²⁾ was laminated. Adhesive is Toyo Morton AD-577-1
And CAT-52 were used, and the coating amount was 3 g / m ^{2 when} dry. Dry at 80 ℃ for about 30 seconds, 40 ℃
Aged for 2 days.

The composition shown in Table 1 was mixed and prepared on the surface of a polyethylene terephthalate film having a thickness of 100 μm of the obtained base material, which was uniformly applied by a dipping method, and further irradiated with ultraviolet rays by a high pressure mercury lamp in air. Thus, an image receiving sheet having a dye receiving layer having a film thickness of 5 to 6 μm was obtained.

(Comparative Example 4) In Example 4, the thickness was 25 μm.
An image receiving sheet was prepared without laminating the transparent polyethylene terephthalate film of m.

A thermal transfer sheet (Mitsubishi SCT-CK100TS) was applied to the dye receiving layer of the image receiving sheet thus obtained.
When the image was formed by facing the transfer layers of the above and using a thermal transfer printer (Mitsubishi SCT-CP100) from the back side of the thermal transfer sheet to form an image, the image receiving sheet of Example 4 had a warp of 3 mm or less. However, the image receiving sheet of Comparative Example 4 had a thickness of 8 mm or more. (However,
The warp value is indicated by the average value of the warped heights at the four corners of the image receiving sheet. )

[0086]

As described above, the image-receiving sheet of the present invention has the high-elasticity resin layer provided on the side of the substrate opposite to the dye-receiving layer. , It does not curl. Therefore, this image receiving sheet is suitable as an image receiving sheet for sublimation type thermal transfer recording.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an example of an image receiving sheet of the present invention.

FIG. 2 is a schematic cross-sectional view showing another example of the image receiving sheet of the present invention.

[Explanation of symbols]

 1 Base Material 2 Dye Receiving Layer 3 High Elasticity Resin Layer 4 Intermediate Layer

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Kazuhiko Sukufu 20-1 Miyukicho, Otake City, Hiroshima Prefecture Mitsubishi Rayon Co., Ltd. Central Research Laboratory

Claims (1)

[Claims] 1. A dye-receptive layer is provided on a substrate, and the elastic modulus is 150 kgf / mm ² or more on the opposite side of the substrate from the dye-receptive layer,
An image-receiving sheet for heat-sensitive transfer recording, further comprising a high-elasticity resin layer having a thickness of 60 μm or less.