JPH02151484A - Thermal transfer image receiving paper - Google Patents

Abstract

PURPOSE:To enhance the light-resistant storage stability of a printing image by forming a membrane layer composed of an ultraviolet curable resin on the dyeing layer provided on a substrate. CONSTITUTION:A dyeing layer consisting of a dyeing resin and an ultraviolet absorber is provided on a substrate and a thin layer composed of a multifunctional acrylic ultraviolet curable resin is provided thereon as an abnormal transfer preventing layer pref. in a dry coating amount of 0.03-1.00g/m<2>. In this image receiving paper, since the ultraviolet absorber is contained in the dyeing layer, the deterioration/discoloration of an image due to the solar rays, especially, ultraviolet rays can be effectively prevented. Further, by the presence of the ultraviolet curable resin film formed on the dyeing layer, the consumption and scattering of the absorber with the elapse of time is reduced and deterioration/discoloration can be effectively prevented over a long period of time. Furthermore, the adhesion of the ink layer by the dyeing layer is prevented by the functional acrylic ultraviolet curable resin layer and abnormal transfer can be effectively prevented.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to an image receiving paper for thermal transfer, particularly an image receiving paper for thermal sublimation printers, and more specifically to an ink paper having an ink layer containing a sublimable dye. The present invention relates to an image-receiving paper used in a thermal recording method in which an ink layer is brought into contact with the image-receiving paper, and a sublimable dye is transferred to the image-receiving paper by heating with a thermal head or the like.

(Prior Art) Hitherto, as dyes used in such thermal sublimation type dyes, highly sublimable dyes have been preferred, and as a result, printed images transferred and recorded onto image-receiving paper have poor image storage stability. Also,
Some image-receiving paper base materials have a dyed layer containing an ultraviolet absorber, but in this case, the softening point of the dyed layer decreases, causing the ink layer to adhere to the dyed layer during heated printing. ,
So-called abnormal transcription occurs. Further, depending on the type of ultraviolet absorber, some have poor high-temperature storage stability, and some have almost no effect on dyes generally used in heat sublimation type transfer recording.

(Problems to be Solved by the Invention) The present invention provides an image-receiving paper capable of improving the conventional drawbacks as described above and improving the light resistance of the printed image recorded on the image-receiving paper.

(Means for Solving the Problem) This problem was solved by using a layer consisting of a dyeing resin and an ultraviolet absorber as a dyeing layer formed on the base material in the conventional image-receiving paper of this type. This problem can be solved by further forming a polyfunctional acrylic ultraviolet curable resin layer on the dyeing layer.

That is, the present invention provides a dyeing layer consisting of a dyeing resin and an ultraviolet absorber, and a polyfunctional dye having a dry coating amount of preferably 0.03 to 1.00 g/rrf on the dyeing layer. The present invention relates to a thermal sublimation image-receiving paper for printers, characterized in that a thin layer of an acrylic ultraviolet curable resin is provided as an abnormal transfer prevention layer.

(Structure and operation of the invention) In the image-receiving paper of the present invention, since the dyed layer contains an ultraviolet absorber, deterioration and discoloration of the image due to ultraviolet rays in sunlight can be effectively prevented. In addition, even if this absorbent is contained in the dyeing layer, due to the presence of the above-mentioned specific ultraviolet curable resin film formed thereon, the absorption agent remains in the dyeing layer and is less likely to wear out and scatter over time. It has the effect of effectively preventing discoloration and deterioration over a period of time.

Furthermore, the polyfunctional acrylic ultraviolet curable resin layer formed on the dye layer prevents the ink layer from adhering to the dye layer, thereby effectively preventing abnormal transfer.

As the substrate for the image-receiving paper used in the present invention, any conventionally used substrate can be used, such as cellulose-based substrates such as natural paper and art coated paper, polyethylene, polypropylene, polycarbonate, and polyethylene terephthalate. Polymer films such as those mentioned above, those whose base materials contain fillers, softeners, etc., and those obtained by stretching these are used. Also used are laminates of these cellulose base materials and these polymer films.

The UV-curable resin used is a photo-crosslinked photoinitiator and polyfunctional acrylic oligomer using UV rays.
Preferably, the crosslinked product has high heat resistance and a softening point of 120.
℃ or higher is better; if the temperature is lower than 120℃, the heat resistance is low, so depending on the type of ink binder in the ink paper, the ink binder may heat-fuse to the ultraviolet curable resin during printing, resulting in a phenomenon called abnormal transfer. Undesirable.

Further, in order to speed up the ultraviolet curing speed, a reactive diluent or a photosensitizer may be used in combination. As polyfunctional oligomers, for example, urethane-acrylate-based Unidaic V-5500, V-4220, V-3208 (Dainippon Ink), epoxy-acrylate-based Unidaic V-
5546 (Dainippon Ink) etc. are used.

As the dyeing resin, any of those conventionally used for this type of thermal transfer image receiving paper can be used, and a typical example is a thermoplastic resin that can be effectively dyed with sublimation dyes. The resin can be used alone or partially crosslinked with a suitable curing agent, but if the degree of crosslinking is too high, the diffusivity of the sublimation dye will decrease, which is undesirable as it will lead to a decrease in color density. Examples of these thermoplastic resins include Byron #200. Thermoplastic high molecular weight polyester resin such as Byron #103 (manufactured by Toyobo Co., Ltd.), ■Poly? -V-
100, P-5001 (manufactured by Unitika), polyamide resins such as Barside 725, Persalon 1140, Persalon 1163 (manufactured by Henkel Hakusui), as well as polyacrylic resins, polyvinyl acetate, polyvinyl Good results can also be obtained with alcohol, styrene-butadiene copolymer, etc.

The ultraviolet absorber is not particularly limited as long as it is a benzophenone-based or benzotriazole-based ultraviolet absorber, but preferably a benzophenone-based one that can prevent fading of the dye when added in a particularly small amount. , specifically 2,4-dihydroxy-benzophenone, 2-hydroxy-4-methoxybenzophenone, 22°-dihydroxy-4-methoxybenzophenone, 2.2″-dihydroxy-4,4°-dihydroxybenzophenone, 2-hydroxy -4-ophtolubenzophenone, 2-hydroxy-4-n-dodecyloxypenzophenone, and the like.

The amount of the ultraviolet absorber used in the present invention is preferably 1% to 40% by weight of the dyeing resin; less than 1% by weight will have little effect on preventing image light resistance, and more than 40% by weight will reduce the UV absorber. bleed, and the image quality tends to deteriorate.

〔Example〕

In order to explain the present invention in more detail, Examples and Comparative Examples are shown below. In addition, "Example Middle" represents parts by weight.

Example 1 100 parts of a saturated polyester resin as a dyeing resin layer and 2-hydroxy-4 as a benzophenone ultraviolet absorber
- A solution of 5 parts of octylhensiphenone mixed uniformly in a organic solvent (toluene/MEK = 4/1 mixed solvent) was coated on art paper, and the thickness after drying was 10 μm.
Forms a dyed layer. Furthermore, as an abnormal transfer prevention layer, acrylic ultraviolet curing resin UNIDIC V-55 is added on top of it.
00 (Dainippon Ink) and photoinitiator Irgacure 17
-806 (Ciba Geigy) was mixed at a weight ratio of 20:1, diluted to 1% with hexane, applied so that the dry coating amount was 0.05 g/rrf, and dried (120
°C for 3 minutes) and cured.

On the image-receiving paper prepared by the above method, a dye represented by the following formula (1) was sublimated and transferred from the ink paper, and magenta color was printed on the dyed layer.

The printing conditions were a linear density of 6 dots/mrs, a recording power of 0.4 W/dot, and the printing pulse width was varied.

The reflected color density was measured using a density system (RD-514) manufactured by Macbeth Co., Ltd., and a light fastness test was performed on those with a density value of 1.5.

The light fastness test was performed using a Sunshine Weather Meter (manufactured by Suga Test Instruments: WEL-3UN-DC) at 50°C for 50 hours, and the color change and fading was measured by the color difference ΔE''.JE'
'' was calculated by measuring the differences in L'', u'', and V'' before and after exposure using a coloring machine (manufactured by Suga Test Instruments: SM Color Computer 5M-3). The results are shown in Figure 1 (
It is shown as A).

Comparative Example 1 An image receiving paper was prepared in the same manner as in Example 1 except that no benzophenone ultraviolet absorber was added, and the same tests as in Example 1 were conducted. The results are shown in FIG. 1 as (B).

Example 2 100 parts of a saturated polyester resin as a dyeing resin and 2-hydroxy-4- as a benzophenone ultraviolet absorber
A solution of 35 parts of methoxybenzophenone and 35 parts of methoxybenzophenone mixed uniformly in an organic solvent (a mixed solvent of toluene/M E K = 4/1) was applied onto polypropylene synthetic paper, and a dyed layer was formed so that the thickness after drying was 10 μm. form. Furthermore, as an abnormal transfer prevention layer, acrylic ultraviolet curable resin UNIDIC V-4220 is diluted to 1% with hexane and dried so that the dry coating amount becomes 0.25 g/rrf.

On the image-receiving paper prepared by the above method, a dye represented by the following formula (2) was sublimated and transferred from the ink paper, and cyan color was printed on the dyed layer.

The printing conditions were the same as in Example 1.

After conducting the light fastness test in the same manner as in Example 1, the discoloration and fading were measured using color difference/E8. The results are shown in Figure 1 (
It was shown as C).

Comparative Example 2 In Example 2, an image receiving paper was prepared in the same manner as in Example 2 except that no benzophenone ultraviolet absorber was added, and the same tests as in Example 2 were conducted. The results are shown in FIG. 1 as (D).

[Brief explanation of the drawing]

FIG. 1 shows the results of the light fastness test, and is a graph showing the relationship between irradiation time and color difference. (that's all)

Claims (1)

[Claims] (1) In image-receiving paper for thermal transfer, on the base material of this image-receiving paper, there is a dyeing layer mainly consisting of a dyeing resin and an ultraviolet absorber, and on the dyeing layer, a polyfunctional acrylic ultraviolet ray An image-receiving paper for thermal transfer characterized by forming a thin film layer of a curable resin.