JPS618387A - thermal transfer recording material - Google Patents

Abstract

PURPOSE:To contrive enhancement of image preservability, by incorporating a UV absorber and/or an anti-oxidant into a heat-fusible ink layer. CONSTITUTION:A heat-fusible ink comprising at least a pigment and/or a dye, a heat-fusible substance, and a UV absorber and/or an anti-oxidant is provided on a transfer sheet base by coating. Accordingly, transferred images with enhanced light resistance can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION (4) Field of Industrial Application The present invention relates to a thermal transfer recording material with improved image storage stability. More specifically, in a thermal transfer recording material consisting of a transfer sheet having a heat-melting ink layer on one side of a base material that can be transferred when heated, and an image-receiving sheet that receives a transferred image from the transfer sheet, The present invention relates to a thermal transfer recording material in which image storage stability is improved by containing an ultraviolet absorber and/or an antioxidant in a meltable ink layer.

@) Prior Art In recent years, color printers and color facsimiles have been actively developed, and interest in color recording is increasing. In particular, thermal transfer recording is easy to maintain due to the simple mechanism of the device, has low price and maintenance costs, is capable of clear, high-density recording with low energy, and uses multi-colored ink sheets. It has recently attracted attention because color recording is relatively easy.

One of the characteristics of color melt-type thermal transfer recording is that it has good image storage stability. However, although the image storability of color melt-type thermal transfer recording is superior to that of dye-sublimation thermal transfer recording or inkjet recording, discoloration or blackening is observed when the printed sample is exposed to sunlight or ultraviolet rays for a long period of time. However, it cannot be said that the light resistance is sufficient for practical use.

In color melt-type thermal transfer recording, organic pigments and dyes are often used as coloring materials contained in the ink layer from the viewpoint of color reproducibility.

It is thought that these organic pigments and dyes are oxidized and degraded by ultraviolet rays, causing discoloration or blackening.

(C) Object of the Invention The present invention was made in view of the above circumstances, and an object thereof is to provide a thermal transfer recording material with improved image storage stability.

(2) Structure of the Invention In other words, the present invention provides a thermal transfer recording comprising a combination of a transfer sheet having a heat-melting ink layer on one side of a base material that can be transferred when heated, and an image receiving sheet that receives a transferred image from the transfer sheet. By containing an ultraviolet absorber and/or an antioxidant in the heat-melting ink layer, a thermal transfer recording material with improved image storage stability could be provided.

That is, the thermofusible ink composition of the present invention comprises at least a pigment and/or dye, a thermofusible substance, an ultraviolet absorber, and/or an antioxidant.

In the present invention, the melting point of the ultraviolet absorber and the antioxidant contained in the heat-melting ink layer is 5° to 150°.
°C is preferred. 4 with a melting point lower than 50'C causes blocking. In addition, one with a melting point higher than 150'C significantly impairs transfer efficiency. Examples of the ultraviolet absorber and antioxidant used in the present invention are listed below. , these do not limit the present invention in any way.

UV absorber p tert-butylphenyl salicyle-1 and
Salicylic acid UV absorbers such as p-octylphenyl salicylate, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone,
2.2'-dihydroxy-4-methoxybenzophenone, 2.2'-dihydroxy-4,4'-dimethoxybenzophenone, and 2-hydroxy-4-methoxy-
Benzphenone UV absorbers such as 5-sulfobenzophenone, 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, 2-(2'-hydroxy-3
', 5'-di-tert,-butylphenyl)benzotriazole, 2-(2'-hydroxy-3' t
ert, -butyl-5'-methylphenyl)-5-chlorobenzotriazole, 2-(2'-hydroxy-3'
, 5'-di*tart,-butylphenyl)-5
-benzotriazole UV absorbers such as chlorobenzotriazole and 2-(2'-hydroxy-4'-octoxyphenyl)benzotriazole, ethyl-2-
Cyanoacrylate UV absorbers such as cyano-3,3'-diphenyl acrylate; UV stabilizers such as nickel-dibutyldithiocarbamate, benzoate-type quenchers and hindered amines; antioxidants; 2,6-di-tert, - Butyl-p-cresol, butylated hydroxyanisole, stearyl-β-(3,
5-diφtert,-butyl-4-hydroxyphenyl)propionate, 2,2'-methylene-bis-(4-
methyl-5-tert,-butylphenol), 2,2
'-methylene-bis-(4-ethyl-6tert,-butylphenol), and tetrakis-(methylene-3
Phenolic antioxidants such as -(3',5'-di-tert,-butyl-4'-hydroxyphenyl)propionate) methane, sulfur-based antioxidants such as simiristylthiodipropionate and distearylthiodipropionate The content of ultraviolet absorbers and antioxidant IE agents such as phosphorus-based antioxidants is determined by the ink serial number on the transfer sheet; the pigments contained and/or
Alternatively, l=Z is preferably 10 to 400% by weight of the dye, and if it is less than 10% by weight, a sufficient effect cannot be obtained;
When the amount is 0% by weight or more, the physical properties of the ink deteriorate, and transferability, peeling, blocking, etc. become worse.

In the present invention, the pigments and dyes contained in the heat-melting ink layer are not limited at all. In general and color melt-type thermal transfer recording, organic pigments and dyes are used for color reproducibility. In the present invention, the effect is remarkable for organic pigments and dyes, but the same effect is shown for inorganic pigments as well.

Organic pigments include azo pigments (monoazo, bisazo, condensed azo pigments), dye lake pigments (acid dye lake, basic dye lake, mordant dye lake pigments), nitro pigments, nitroso pigments, phthalocyanine pigments, and high-grade pigments (vat dye lake pigments). Examples include dye pigments, metal complex salt pigments, perylene pigments, isoindolinone pigments, and quinacridone pigments). More specific examples include Pyrazolone Red B (21120), Permanent Red R (12085), Lake L/D C (1
5585), Brilliant Carmine 6B (15850)
, Hermanent Carmine FB (12490) (all monoazo pigments), Benzidine Yellow G (21090), Penzidine E o-GR (21100), Permanent xo
-NCR (20040) (bisazo pigment), chromophthal yellow, chromophthal red (condensed azo pigment) fx, etc.

As a dyeing lake pigment, quinoline yellow lake (47
005), Eosin Lake (45380), Alkaline Blue Lake (42750A, 42770A) (all acid dye lake pigments), Rhodamine Lake B (45170)
, Methyl Violet Lake (42535), Victoria Blue Lake (44045), Malachite Green Lake (42000) (all basic dye lake pigments), Alizarin Lake (58000) (mordant dye lake pigment)
etc. are al. Naphthol Yellow 5 (1) as a nitro pigment
0316), Pigment Green B as a nitroso pigment
(10006), Naphthol Green B (10020)
, as phthalocyanine pigments, metal-free phthalocyanine blue (74100), phthalocyanine blue (741
60) and Phthalocyanine Green (74260). As a high-grade pigment, anthrapyrimidine yellow (
68420), Indanthrene Brilliant Orange G
K (59305), Indan Stremburu-R8 (698
00), Thioindigo Red B (73300) (vat dye pigments), Nickel Azo Yellow (12775) (
perylene red (71140), perylene scarlet (71137) (all perylene pigments)
, isoindolinone yellow (isoindolinone pigment),
Examples include Quinacridone Red Y (46500) and Quinacridone Redta (73J915).

Dyes include nitrone dyes, nitro dyes, azo dyes, azo dyes (mono, bis, tris, and tetrakisazo dyes)5, stilbene azo dyes, keimine (diphenylmethane) dyes, triphenylmethane dyes, xanthine dyes, acridine dyes, and quinoline dyes. Examples include dyes, methine/polymethine dyes, thiazole dyes, indamine e-indophenol dyes, azine dyes, oxazine dyes, thiazine dyes, sulfur dyes, aminoketone-oxyketone dyes, anthraquinone dyes, indigoid dyes, and phthalocyanine dyes. To give more specific examples, the nitroso dye is Mordant Geline 4 (C, 1, 10005, hereinafter C, 1, A is shown in parentheses), the nitro dye is Disbirds Yellow 14 (10340), and the azo dye. The dye is Direct Red 28 (22120), and the stilbene azo dye is Direct Orange 71 (40205).
), Basic Yellow 2 (41000) as a keimine (diphenylmethane) dye, Basic Blue 1 (42025) as a triphenylmethane dye, and Acid Red 52 (45100) as a xanthine dye.
, Basic Orange 23 (4) as an acridine dye.
6f175), Acid Yellow 2 (47010) as a quinoline dye, Disbirds Yellow 31 (48000) as a methine/polymethine dye, Fu Direct Yellow 59<49000) as a thiazole dye,
Indamine/indophenol dyes include Solvent Blue 22 (49705), azine dyes include Acid Blue 59 (50315), oxazine dyes include Mordand Blue 10 (51030), thiazine dyes include Basic Blue 9 (52015), and aminoketone dyes. As an oxyketone dye, Bat Red 33 (56
050), Acid Blue 45 (63010) as an anthraquinone dye, Bat Blue 41 (730'40) as an indigoid dye, and Direct Blue 86 (74180) as a phthalocyanine dye.

Examples of pure pigments include oxides, sulfides, selenides, ferrocyanides, chromates, silicates, and phosphoric acids. To give a more specific example, examples of oxides include red iron (C, I).

77491 (hereinafter in parentheses indicates C, 1), cobalt blue (77346), red lead (77578), cobalt green, chromium oxide (77288), cerulean blue (77368), viridian (77289), and yellow oxide Iron (77492), sulfides include cadmium yellow 177199), silver vermilion (77766), and selenides include Prussian blue (77510777).
520), and as a chromate, chrome yellow (77
600), chromium vermilion (77605), zinc chromate-1-(77955), barium chromate (77
955), ultramarine (7700) as a silicate
7), phosphates include Cobalt Violet Deep (77360) and Manganese Violet 1- (7774).
2) etc.

The thermofusible substance and L:'cFi paraffin wax, carnauba wax, montan wax, polyethylene 17x, synthetic wax, solid fatty acid, solid amide, etc. having a melting point of 50 to 150°C are used.

[This ink layer may contain thermoplastic polymeric substances such as petroleum resins, polyvinyl acetate, polystyrene, styrene-butadiene copolymers, cellulose ethers, cellulose esters, and acrylic resins, or Oily substances such as mineral oil, animal oil, vegetable oil, and plasticizers can also be added as softeners.

A heat-melting ink containing the above components is applied to a transfer sheet base material.

As a transfer sheet base material, the thickness is 3-25μ and the band gap is 0.9-
1.4g-/7 plastic film (polyester, polyimide, cellophane, etc.) or paper (condenser paper,
Synthetic paper, laminated paper, etc.) are used.

The ink is applied using general hot melt coating or solvent coating.
It is also possible to apply as a water-based coating liquid.

Paper, plastic film, synthetic paper, etc. can be used as the image-receiving sheet. Because it contains all
A transferred image with extremely excellent light resistance can be obtained.

The following two examples are shown to more specifically explain the present invention, but the present invention is of course not limited to these. In addition, parts in the examples indicate parts by weight.

(E) Examples Example 1 Yellow, magenta and cyan inks having the compositions shown in Table 1 were prepared.

These inks have a thickness of 13μ and a density of 0.90? 4.0P/2 sheets of condenser paper with hot melt coater
-A transfer sheet was obtained by coating.

As the image-receiving sheet, plain paper with a tsubo of 55 f/m' was used.

The ink layer surface of the transfer sheet and the image receiving sheet were overlapped, and a pulse width of 2.0 m5ec was applied from the back side of the transfer sheet using a facsimile tester manufactured by Matsushita Electronic Components.

'to pressure 16. Three colors of yellow, magenta and cyan were printed using OV.

Table 1 Ink Composition Example 2 Using 2-hydroxy-4-methoxybenzophenone instead of p-tert, -butylphenyl salicylate in Example 1, a transfer sheet was prepared in the same manner as in Example 1, and printing was performed. went.

Example 3 In place of p-tert, -butylphenyl salicylate in Example 1, 15 parts of 2-(2'-hydroxy-4'-octoxyphenyl)benzo) +71 sol was used, and the following Example 1 was carried out. The same procedure as [trowel transfer sheet H- was prepared and one printing was performed.

Example 4 An image-receiving sheet was prepared in the same manner as in Example 1, using 2,6-tert,-butyl-p-cresol instead of p-tert,-butylphenyl salicylate in Example 1. 1 printing was performed.

Comparative Example Yellow, magenta and cyan inks having the compositions shown in Table 2 were prepared.

A transfer sheet was prepared using this in the same manner as in Example 1,
The printed sample obtained as above was left under sunlight and in a xenon long life fade meter HAL-25X-HCL manufactured by Suga Test Instruments Co., Ltd., and changes in reflection density over time were measured using a Macbeth densitometer. Measured at

The residual rate of absorbance was determined using the following formula.

Table 2 Ink composition: If the residual rate is 100% or less, the color will fade.
A value of 100% or more indicates black discoloration.

The measurement results are shown in Table 3. This clearly shows that the recorded images of the present invention have excellent storage stability.

*4. Effects of the invention Images recorded using the transfer sheet of the present invention have significantly improved storage stability compared to those recorded using conventional transfer sheets, and are superior to color melt-type images. The present invention has extremely high industrial significance in further enhancing the advantages of thermal transfer recording.

Claims (1)

[Claims] A thermal transfer recording material comprising a combination of a transfer sheet having a heat-melting ink layer that can be transferred when heated on one side of a base material, and an image receiving sheet that receives a transferred image from the transfer sheet,
A thermal transfer recording material characterized in that the heat-melting ink layer contains an ultraviolet absorber and/or an antioxidant.