JP2008194875A - Thermal transfer ribbon and thermal protection layer transfer sheet - Google Patents

Abstract

An object is to provide a heat-sensitive transfer ribbon and a heat-sensitive protective layer transfer sheet capable of improving the light resistance of a print to be protected without impairing transparency or the like.
The thermal transfer main ribbon of the present invention is a thermal transfer ribbon in which at least a sublimable dye region and a thermal transfer transparent protective layer are provided on a substrate in the surface order, and the thermal transfer transparent protective layer is an ultraviolet ray. It is a thermal transfer ribbon characterized by containing at least one selected from compounds represented by formulas (1) to (3) as an absorbent.
[Selection] Figure 1

Description

  The present invention relates to a heat-sensitive transfer ribbon and a heat-sensitive protective layer transfer sheet, and more particularly, to a heat-sensitive transfer ribbon and a heat-sensitive ribbon having a heat-sensitive transfer transparent protective layer that can improve the light resistance of a print to be protected without impairing transparency. The present invention relates to a protective layer transfer sheet.

  In recent years, thermal transfer type sublimation recording devices have been used as a means of easily creating ID cards, etc. due to their superior operability and maintainability, and excellent gradation images such as facial photographs. Widely used. The thermal transfer ribbon used in such an apparatus is provided with a dye layer containing a sublimable dye and a binder on one surface of a base material such as polyester, and the thermal energy is applied from the base material side by a thermal head or the like. Printing is performed by transferring the sublimable dye in the layer to a transfer material such as image receiving paper.

  However, when the sublimation type thermal transfer ribbon as described above is used, a gradation image such as a face photograph can be accurately formed. Due to the influence of the above, there was a problem that the light resistance was inferior.

  As a means for solving such problems, as one of the layers constituting the thermal transfer ribbon, a transparent protective layer formed by dissolving, applying, and drying an ultraviolet absorbent together with a resin in a solvent or the like is provided. . This transparent protective layer improves light resistance by forming a transparent protective layer on the image when thermally transferred.

  On the other hand, a transparent protective layer is formed by transferring a protective layer onto an image created by a conventional thermal transfer ribbon or an ink jet printer using a thermal protective layer transfer sheet different from the above thermal transfer ribbon. ing. The transparent protective layer of the heat-sensitive protective layer transfer sheet contains an ultraviolet absorber dissolved, applied and dried together with a resin in a solvent or the like for the purpose of improving light resistance.

  As ultraviolet absorbers used for the above-mentioned purposes, organic ultraviolet absorbers such as benzotriazole and benzophenone and inorganic ultraviolet absorbers such as ultrafine titanium oxide are generally used. (See Patent Documents 1 and 2)

JP 2006-21333 A JP 7-156567 A

  However, generally used organic ultraviolet absorbers such as benzotriazole and benzophenone are substituted at the ortho position of the benzene ring with a hydroxy group, so that the vicinity of 350 nm to 400 nm close to the visible light region. Therefore, when these ultraviolet absorbers are applied to the heat-sensitive transfer transparent protective layer, yellow color is imparted as initial coloring, which causes deterioration in image quality. When inorganic UV absorbers such as fine particle titanium oxide are used in combination with these organic UV absorbers, yellowing due to metal ions in the UV absorber is severe, and organic UV absorbers and inorganic UV absorbers are used. It was difficult to use together.

  The present invention has been made in order to solve the problems of such a conventional configuration, and is a thermal transfer capable of improving the light resistance of a print to be protected without impairing transparency or the like. An object of the present invention is to provide a ribbon and a heat-sensitive protective layer transfer sheet.

で表される化合物から選ばれる少なくとも１種を含有していることを特徴とする感熱転写リボンである。 And, in order to achieve the above object, the thermal transfer ribbon of the present invention is a thermal transfer ribbon in which at least a sublimable dye region and a thermal transfer transparent protective layer are provided in a surface sequence on a substrate. The thermal transfer transparent protective layer is used as an ultraviolet absorber in the following formulas (1) to (3):

A thermal transfer ribbon characterized by containing at least one selected from the compounds represented by:

で表される化合物から選ばれる少なくとも１種を含有していることを特徴とする感熱保護層転写シートである。 The heat-sensitive protective layer transfer sheet of the present invention is a heat-sensitive protective layer transfer sheet in which a heat-sensitive transfer transparent protective layer is provided on a substrate, and the heat-sensitive transfer transparent protective layer has the following formulas (1) to (3) as an ultraviolet absorber. :

A heat-sensitive protective layer transfer sheet comprising at least one selected from the compounds represented by formula (1).

  According to the present invention, it is possible to provide a heat-sensitive transfer ribbon and a heat-sensitive protective layer transfer sheet that can improve the light resistance of a print to be protected without impairing transparency or the like.

  The specific ultraviolet absorber used in the present invention does not have an absorption peak in a region close to visible light of 350 nm to 400 nm because the ortho position of the benzene ring is not substituted with a hydroxy group, and therefore yellow as an initial coloration. Gives little taste. In addition, since yellowing caused by metal ions can be suppressed even when used in combination with an inorganic ultraviolet absorber, it is possible to suppress deterioration in the quality of printed matter even when exposed to light for a long period of time.

  As the substrate used in the present invention, a conventional film having a certain degree of heat resistance and strength can be used. For example, various processed papers, polyester films including polyethylene terephthalate films, polystyrene films, polypropylene films, polysulfone films, 1,4-polycyclohexylene dimethyl terephthalate films, cellophane and the like can be mentioned. Among these, a polyethylene terephthalate film is particularly preferable. The thickness is preferably 0.5 to 50 μm, and more preferably about 3 to 10 μm. In addition, you may provide an easily bonding layer in order to make adhesion | attachment with another layer easy on the surface of a film as needed. Moreover, you may use the commercially available film already provided with the easily bonding layer.

  This easy-adhesion layer can be formed using a urethane resin, a polyester resin, a polypropylene resin, a polyol resin, a reaction product of these resins with isocyanates, and the like. Examples of the isocyanate used include conventionally used diisocyanate compounds and triisocyanate compounds. The easy adhesion layer is preferably formed so as to have a thickness of 0.1 to 10 μm.

  Each dye layer in the sublimation dye region provided on the thermal transfer ribbon of the present invention is a layer in which a sublimation dye is supported by an arbitrary binder resin. As the dye to be used, any dye that melts, diffuses or sublimates and transitions by heat, and any of the dyes conventionally used for thermal transfer ribbons can be used. Preferred dyes include, for example, methine series such as diarylmethane series, triarylmethane series, thiazole series, merocyanine, indoaniline, acetophenone azomethine, pyrazoloazomethine, imidazole azomethine, imidazoazomethine, azomethine series represented by pyridone azomethine, Xanthene, oxazine, dicyanostyrene, cyanomethylene, represented by tricyanostyrene, thiazine, azine, acridine, benzeneazo, pyridoneazo, thiophenazo, isothiazoleazo, pyrroleazo, pyralazo, imidazoleazo, thiadiazoleazo Azo, such as triazole azo and disazo, spiropyran, indolinospiropyran, fluorane, rhodamine lactam, naphthoquinone, anthra Non-based, quinophthalone, and the like.

  Specifically, as cyan dyes, Kayaset Blue 714 (Solvent Blue 63, manufactured by Nippon Kayaku), Foron Brilliant Blue-SR (Disperse Blue 354, manufactured by Sand), Waxolin AP-FW (Solvent Blue 36, ICI), as magenta dye, MS-REDG (DisperThread 60, manufactured by Mitsui Toatsu), Macrolex Violet R (Disperse Violet 26, manufactured by Bayer), and yellow dye Foron Brilliant Yellow S-6GL (Disperse Yellow 231) ), Macrolex Yellow 6G (Disperse Yellow 201, manufactured by Bayer), and the like.

  As the binder resin for supporting the dye, known resins can be used, for example, cellulose resins such as ethyl cellulose, ethyl hydroxy cellulose, hydroxypropyl cellulose, methyl cellulose, cellulose acetate, polyvinyl alcohol, polyvinyl acetate, polyvinyl Sublimation dye layer regions such as butyral, polyvinyl acetal, polyvinyl pyrrolidone, and the like are added to the above-described dye and binder resin as necessary, and various additives are added, and dissolved in an appropriate organic solvent or dispersed in an organic solvent or water. The dispersion is formed by applying and drying on a substrate by gravure printing, screen printing or the like so that the thickness is 0.2 to 5.0 μm, preferably 0.4 to 2.0 μm. Can do.

(Thermal transfer transparent protective layer)
The heat-sensitive transfer transparent protective layer (hereinafter also referred to as “transparent resin protective layer”) in the present invention may be a single layer, or a multi-layered transparency such as a release layer, a transparent resin layer, and an adhesive layer. It is good also as a resin protective layer, and you may provide a release layer between a base material and a transparent resin protective layer in order to improve the transferability of a transparent resin protective layer as needed (refer FIG. 1).
In the present invention, the ultraviolet absorber contained in the transparent resin protective layer may be contained in any layer when the transparent resin protective layer has a multilayer structure as described above. Below, each layer which forms a transparent resin protective layer is demonstrated.

(Release layer)
The release layer facilitates the transfer of the transparent resin protective layer, and most or all of itself remains on the substrate side. Such a release layer can be formed of a resin such as waxes, silicone resin, fluororesin, acrylic resin, cellulose resin, styrene acrylic resin. These may be used alone or in combination. The release layer is coated with the above resin by a gravure printing method or a screen printing method so that the layer thickness is about 0.1 to 2.0 μm, or through another layer, and dried. Can be formed. In addition, when it is desired that the transparent resin protective layer after the transfer has been matted, use various types of particles in the release layer or use a base film whose surface is matted. Thus, the surface of the transparent resin protective layer after transfer can be formed into a mat shape.

(Peeling layer)
The release layer is a layer that facilitates transfer of the transparent resin layer and is also transferred together as a member of the transparent resin protective layer. Such a release layer can be formed from a resin having excellent transparency, wear resistance, chemical resistance, and the like, such as an acrylic resin, an epoxy resin, a polyester resin, and a styrene resin. The release layer is prepared by preparing a solution of the appropriate resin as described above, and using a gravure printing method, a screen method, or the like so that the layer thickness is about 0.2 to 4.0 μm. It can be formed by coating and drying through another layer. In order to improve transferability, a filler such as silica or alumina may be added. Furthermore, waxes such as polyethylene wax may be added in order to improve wear resistance, slipperiness and transferability.

(Adhesive layer)
The adhesive layer is a layer that is provided on the transparent resin layer as necessary to facilitate adhesion with the transfer material and is the uppermost layer. The adhesive layer is formed from a resin that exhibits good adhesion when heated. Examples of the resin include resins such as acrylic resins, vinyl chloride resins, vinyl acetate resins, vinyl chloride-vinyl acetate copolymer resins, polyester resins, polyamide resins, chlorinated polypropylene resins, and polyurethane resins. In order to improve the sharpness at the time of transfer, a filler such as silica or alumina may be added. For the adhesive layer, the appropriate resin solution described above is prepared, and this is applied to the transparent resin layer or other layers by gravure printing or screen printing so that the layer thickness is about 0.1 to 2.0 μm. It can be formed by coating and drying through the substrate.

(Transparent resin layer)
The transparent resin layer can be appropriately selected in consideration of friction resistance, transparency, hardness, etc., for example, polyester resin, acrylic resin, polystyrene resin, polyurethane resin, acrylic urethane resin, silicone modification of these resins Examples thereof include resins. These may be used alone or in combination.
A resin obtained by crosslinking an acrylic monomer by ionizing radiation irradiation can also be used. Specific examples of acrylic monomers include ethylene glycol di (meth) acrylate, hexanediol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, trimethylolpropane di (meth) acrylate, pentaerythritol tetra (meth) acrylate, Examples include dipentaerythritol hexa (meth) acrylate, ethylene glycol diglycidyl ether di (meth) acrylate, propylene glycol diglycidyl ether di (meth) acrylate, and sorbitol tetraglycidyl ether tetra (meth) acrylate. Moreover, the substance hardened | cured by ionizing radiation may be used not only as said monomer but as an oligomer. Further, acrylic reactive polymers such as polyester acrylates, epoxy acrylates, urethane acrylates and the like made of the above polymers or derivatives thereof can also be used. Furthermore, you may mix and use with another acrylic resin. Further, a filler such as silica or alumina may be added in consideration of sharpness at the time of transfer of these resins.

In the present invention, the ultraviolet absorbers of the above formulas (1) to (3) are added to at least one of the release layer, the transparent resin layer, and the adhesive layer. The ultraviolet absorbers of the above formulas (1) to (3) may be used alone or in combination, and other ultraviolet absorbers such as benzotriazoles and benzophenones may be used without departing from the spirit of the present invention. An organic ultraviolet absorber or an inorganic ultraviolet absorber such as fine particle titanium oxide or cerium oxide may be added. However, when adding another ultraviolet absorber, when the total amount of the ultraviolet absorbers of the above formulas (1) to (3) is 100 parts, it is preferably less than 50 parts. If added over 50 parts, yellowing of the transparent resin protective layer becomes severe and the quality of the printed matter may be lowered.
The added amount of the ultraviolet absorber is at least 10 to 90 parts, preferably 30 to 70 parts per 100 parts of the binder constituting each layer. If it is less than the above range, it is difficult to obtain desired light resistance, and if it is added in excess of the above range, the desired properties of each layer described above will deteriorate.

  The transfer material for transferring an image using the thermal transfer ribbon of the present invention and forming the thermal transfer transparent protective layer is not particularly limited as long as it has a dyeing property with respect to sublimation dyes of each color, For example, a heat-sensitive transfer image receiving paper having a dyeable receiving layer made of polyvinyl chloride resin, polyester resin, polycarbonate resin, acrylonitrile styrene resin or the like on a substrate can be used.

  When using the thermal transfer ribbon of the present invention, the sublimation dye region of the thermal transfer ribbon is overlaid on the above-mentioned transfer material, and a desired color image is formed by a heating means such as a thermal head or a laser. In the same manner, a heat-sensitive transfer transparent protective layer is transferred onto the printed image. The thermal transfer transparent protective layer may be transferred to the entire surface of the formed image or may be transferred to an arbitrary shape.

  The heat-sensitive protective layer transfer sheet of the present invention is formed by providing a heat-sensitive transfer transparent resin layer on a substrate. The base material and the thermal transfer transparent resin layer used for the thermal protection layer transfer sheet are the same as those described for the thermal transfer ribbon, and can be formed in the same manner. Moreover, you may provide layers other than a transparent resin protective layer as needed.

  This thermal transfer protective layer transfer sheet can be applied not only to an image formed with a sublimation thermal transfer ribbon, but also to an image formed with a hot-melt thermal transfer ribbon or inkjet.

  In order to use the heat-sensitive protective layer transfer sheet of the present invention, a heat-sensitive transfer transparent resin layer may be superimposed on the formed image, and the heat-sensitive transfer transparent resin layer may be transferred by a heating means such as a thermal head, a laser, or an iron.

  Hereinafter, the present invention will be described in further detail with reference to Examples and Comparative Examples, but the present invention is not limited to these. In this example, the thermal transfer ribbon shown in FIG. 2 having the configuration of the thermal transfer transparent protective layer shown in FIG. 1 was produced. However, in this example, since the transparent resin layer also serves as the adhesive layer, no adhesive layer was provided.

(Example 1)
(Production of thermal transfer ribbon)
First, yellow, magenta, and cyan inks containing a sublimable dye having the following composition were prepared.

<Yellow ink>
5.5 parts by weight of yellow dye (Macrolex Yellow 6G, manufactured by Bayer)
Polyvinyl butyral resin 4.5 parts by weight (ESREC BX-1, Sekisui Chemical)
Methyl ethyl ketone / toluene (weight ratio 1/1) 90.0 parts by weight

<Magenta ink>
It was the same as yellow ink except that magenta dye (Disperse Red 60) was used instead of yellow dye.

<Cyan ink>
It was the same as the yellow ink except that a cyan dye (Solvent Blue 63) was used instead of the yellow dye.

<Black ink>
A black ink having the following composition was used.
Carbon black (MA-8, manufactured by Mitsubishi Chemical) 15.0 parts by weight Polyester resin 15.0 parts by weight (Diacron ER1002, manufactured by Mitsubishi Rayon)
Methyl ethyl ketone / toluene (weight ratio 1/1) 70.0 parts by weight

  As the substrate, a polyethylene terephthalate film having a thickness of 4.5 μm was used. A silicone resin was applied to one surface of the film so that the layer thickness after drying was 1.2 μm and dried to form a heat-resistant protective layer.

Next, on the surface opposite to the surface on which the heat-resistant protective layer is formed, each of yellow, magenta, cyan and black inks is applied with a gravure coater so that the layer thickness after drying is about 1.0 μm. And dried to form yellow, magenta, and cyan sublimation ink layers and a black hot-melt ink layer in the surface order.
Next, a release layer ink, a release layer ink, and a transparent resin layer ink having the following composition were prepared.

<Release layer ink>
Diacetyl cellulose (L-30, manufactured by Daicel Chemical Industries) 5.0 parts by weight Methyl ethyl ketone 95.0 parts by weight

<Ink for release layer>
Acrylic resin 90.0 parts by weight (UNO-1, one-component curing type, solid content 40%, manufactured by Gifu Shellac Factory)
Isopropyl alcohol 5.0 parts by weight Methanol 5.0 parts by weight

<Ink for transparent resin layer>
Acrylic resin 10.0 parts by weight (BR-83, manufactured by Mitsubishi Rayon)
7.0 parts by weight of UV absorber of formula (1) (manufactured by Hostabin PR-25 Clariant)
Methyl ethyl ketone / toluene (weight ratio 1/1) 83.0 parts by weight

  Next, the ink for the release layer is applied to the portion where the sublimable ink layer and the hot-melt ink layer are not formed with a gravure coater so that the layer thickness after drying is 0.2 μm, and then peeled off. Apply the layer ink after drying so that the layer thickness becomes 0.6 μm, and further apply the transparent resin layer ink with a gravure coater so that the layer thickness after drying becomes 2.0 μm. The heat-sensitive transfer transparent protective layer composed of a release layer, a release layer and a transparent resin layer is formed in the surface order with the sublimation ink layer and the heat-melting ink layer to produce the heat-sensitive transfer ribbon according to the present invention. did.

(Examples 2 to 17 and Comparative Examples 1 to 4)
A thermal transfer ribbon was produced in the same manner as in Example 1 except that the release layer and the transparent resin layer were changed to the formulation shown in Table 1.

[Characteristic evaluation]
(Light resistance)
The respective thermal transfer ribbons obtained in Examples 1 to 17 and Comparative Examples 1 to 4 were set in place of the sublimation transfer ribbon dedicated to the sublimation type thermal transfer printer (Digital Photo Printer SPP-2020) manufactured by Samsung. An image was printed on a printer-dedicated paper, and then a transparent resin protective layer was transferred to prepare a sample for evaluation. The marking screen of the obtained sample was irradiated with a fade tester (XENONTESTER XW-1500, manufactured by SHIMAZU) for 24 hours, and the change in image (difference (ΔE) between the OD value before irradiation and the OD value after irradiation) was measured. RD-914 (made by Gretag Macbeth) was used for the measuring device, and the evaluation criteria were as follows. The results are shown in Table 2.
○: ΔE is within 0.5 Δ: ΔE is greater than 0.5

(Surface reflection characteristics)
The surface reflection characteristics of the image receiving paper before printing on a sublimation type thermal transfer printer (Digital Photo Printer SPP-2020) manufactured by Samsung are measured by the method specified in JIS Z 8722 (spectrino manufactured by Gretag Macbeth Co., Ltd.). The b value when displayed by the method specified by 8730 is b ₀ , the sensitivity of the thermal transfer ribbons obtained in the examples and comparative examples on the image receiving paper dedicated to the sublimation type thermal transfer printer (Digital Photo Printer SPP-2020) manufactured by Samsung. measuring the samples transferred only thermal transfer transparent TatsukiMamoruso a similar manner, the display was b value and b _1, and was then evaluated for change Kido by Δb = b ₁ -b _0. Further, after exposing the resulting sample to sunlight for 10 days, the yellow index was measured in the same manner, the display was b value and b _2, also assess changes in Kido by Δb _{2 =} b 2 -b ₀ did. The evaluation criteria were as follows. The results are shown in Table 2.
○: Δb is less than 0.2 Δ: Δb is 0.2 or more and less than 0.4 ×: Δb is 0.4 or more ○: Δb ₂ is less than 0.3 Δ: Δb ₂ is 0.3 or more and less than 0.5 X: Δb ₂ is 0.5 or more

It is sectional drawing which shows the structure of the thermal transfer transparent protective layer in this invention. It is a top view which shows the thermal transfer ribbon of this invention.

Claims (2)

In a thermal transfer ribbon in which at least a sublimable dye region and a thermal transfer transparent protective layer are provided in the surface order on a substrate, the thermal transfer transparent protective layer is represented by the following formulas (1) to (3) as ultraviolet absorbers:

A thermal transfer ribbon comprising at least one selected from the compounds represented by formula (1). In the heat-sensitive protective layer transfer sheet in which a heat-sensitive transfer transparent protective layer is provided on a substrate, the heat-sensitive transparent transparent protective layer is represented by the following formulas (1) to (3) as ultraviolet absorbers:

A heat-sensitive protective layer transfer sheet comprising at least one selected from the compounds represented by formula (1).

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