JPS5985792A - Image-receiving body for thermal transfer recording - Google Patents

Abstract

PURPOSE:To provide the titled image-receiving body improved in disturbance of image quality due to ruggedness or undulation of the surface of an image- receiving layer, useful for a video printer or the like and stable to environments, wherein an image-receiving layer is provided on a base coated with a smoothened layer. CONSTITUTION:A hot-melt liquid consisting of a binder such as carnauba wax and a softener such as an oil is applied onto the base 13 such as a paper, followed by driving to produce the smoothened layer 12. Further, a mixture of a high molecular material such as a polyester and an inorganic material such as clay is applied onto the layer 12 to produce the image-receiving layer 11, thereby producing the objective image-receiving body wherein the ruggedness 14 of the surface is preferably within 3mu and the undulation 15 of the surface is preferably within 10mu/mm..

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an image receptor for thermal transfer recording, and particularly to a color hard copy used in a video printer or the like that forms characters or images on the receptor using electrical signals from a thermal head or the like. .

Conventional Structure and Problems In the transfer type thermal recording method using a heat source controlled by an electric signal VC such as a thermal head, as shown in FIG. A color hard copy is obtained by sandwiching a receptor 1 having a receptor layer 11 and a substrate 13 between a drum 3 and a heat source 4, and transferring a layer 220 color material onto the image receptor layer 11 in response to an electrical signal. ing. The structure of the receptor used in this method is conventionally shown in Figure 2 (
As in a), an image receiving layer 11 is provided on a substrate 13.

The image-receiving layer 11 differs depending on the content of the coloring material used. In the case of a heat-melting type coloring material containing a pigment, the substrate 13 itself may be used; in the case of a sublimable basic dye type coloring material, activated clay ( In the case of a sublimable disperse dye type hue, the active clay layer is composed of a polymeric particle layer such as polyester. In conventional receptors, the surface 14 of the image-receiving layer 11 has a thickness of 5 to 1571 mm as shown in the figure due to uneven thickness of the substrate 13 or surface irregularities.
There is an unevenness of m, and as shown in 15, 1 per crystal.
There was a undulation of 0 to 20/Im. This enlarged view is the second
Shown in Figures (b) and (C). 14' in FIG. 2(b) is the size of the unevenness, and 15 in FIG. 2(C) is the size of the waviness. Even when surface treatment using a supercalender is used, there is a limit to the level of unevenness or waviness, which can only be improved to some extent. For this reason, if the color fading transferred from the coloring material layer 22, the surface unevenness of the image-receiving layer 11 is 3 to 671 m or more, or the undulation is 10 μm or more per wave, the image signal will not be affected by not only heat-melting coloring materials but also sublimation coloring materials. The image quality was not accurately transferred depending on the color, resulting in disturbances in image quality such as missing dots and missing dots, resulting in a grainy feeling in the middle tones.

Furthermore, especially in the case of a dyed pattern color control layer, there is a problem that the dyeing 11 is damaged by environmental conditions such as humidity and ultraviolet rays due to impurities such as nitrogen atoms or sulfuric acid radicals contained in the substrate 13 such as paper. there were.

OBJECTS OF THE INVENTION An object of the present invention is to provide an image receptor having environmental stability that improves image quality disturbances caused by unevenness and waviness on the surface of an image-receiving layer.

Structure of the Invention The present invention is an image receptor for thermal transfer recording, in which an image receiving layer is provided on a substrate whose surface is coated with a smoothing layer.

DESCRIPTION OF EMBODIMENTS FIGS. 3 and 4 show sectional views of the basic structure of the receptor of the present invention. The image receptor 1 consists of a substrate 13, a smoothing layer 12, and an image receiving layer 11. 14 indicates unevenness on the surface of the image-receiving layer, and 15 indicates undulations on the surface. In order for the surface of the image-receiving layer to be in contact with the hue layer 22 and receive the coloring material by sublimation or heat-melting transfer of the coloring material, it should have an unevenness of up to 311 m or a undulation of up to 10 l1m per layer. is necessary.

On the other hand, pigment-based colorants have excellent humidity and light stability, but
It has been demonstrated that dye-based colorants become unstable in the presence of impurities.

By forming the smoothing layer of the present invention with a material that prevents impurities from penetrating from the substrate, it is possible to obtain the same level of stability as pigment-based hues.

(Example 1) As the substrate 13, an inorganic material such as white earth, alumina, lyca, zinc oxide, etc. is used as a smoothing layer on a coated paper such as baryta paper, art paper, machine coated paper, cast coated paper, or gravure paper. A liquid containing a binder such as styrene frigiene rubber (hereinafter referred to as SBR) at a weight ratio of 8:2 was coated with a blade coater to a thickness of about 10 μm and dried, and an image-receiving layer was formed on this. In a configuration using an inorganic acid color developer such as activated clay, or an organic acid color developer such as phenol resin or a metal salt of a salicylic acid derivative, coated with SBR as a binder to a thickness of 10 μm,
The unevenness of the surface of the image-receiving layer is 0.6 μm, the waviness is within 17 tm per layer, and the Bekk smoothness is 1000 to 2000.
I got the value in seconds.

(Example 2) A smoothing layer was prepared using a binder such as carnauba wax or ester wax and a softener such as oil in a weight ratio of 9:1 on plain paper with a Bekk smoothness of 100 to 500 seconds as the substrate 13.
The hot melt solution contained in the moving table 1 was coated with a blade coater to a thickness of about 20 μm and dried, and the image-receiving layer was made of polymeric materials such as polyester, acetate, lye, and white earth, alumina, phosphor, etc. In a structure in which a mixture of inorganic materials such as zinc oxide is coated to a thickness of 1 to 571 m, the unevenness of the image-receiving layer surface is within 37 zm, the waviness is within 61 tm per layer, and the Bekk smoothness is 8 oO to 15 oO.
I got the value in seconds.

(Example 3) A polymeric material such as acrylic, polyester, acetate, polyethylene, polyamide, polyamide, polysulfone, polycarbonate, etc. is used as a smoothing layer on plain paper with a Bekk smoothness of 100 to 500 seconds as the substrate 13. 1
A weeping solution mixed with 9 parts by weight of a solvent was coated and dried to a thickness of about 10 μm using a blade coater, and activated clay was coated to a thickness of 10 μm together with an SBR binder as an image-receiving layer. With this configuration, the light fastness of the dyed image was improved from less than grade 1 to grade 3 according to the JIS standard, and improved to the level of silver halide photography. In addition, in the above explanation, the base body 13
Although paper has been described above, it is also true that the same effect can be obtained using polymeric films such as polyester or acetate.

Effect of the invention The configuration of the present invention provides the effects listed below.

(1) The coloring material is accurately transferred from the transfer body to the image-receiving layer according to the magnitude of the image signal, resulting in improved image reproducibility and elimination of roughness in intermediate tones.

(2) Due to the presence of the smoothing layer, the dye-type coloring material has improved moisture resistance.
Light resistance stability has been improved.

(3) The presence of the smoothing layer acted as a reflector for incident light, improving the saturation of the entire image.

[Brief explanation of drawings]

Figure 1 is a sectional view explaining transfer type thermal recording, Figure 2 (a
), (b), and (C) are block diagrams of a conventional image receptor, and FIGS. 3 and 4 are block diagrams of an image receptor according to an embodiment of the present invention. DESCRIPTION OF SYMBOLS 1... Image receptor, 13... Substrate, 12... Smoothing layer, 11... Image receiving layer. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2 Figure 3v! i

Claims (4)

[Claims] (1) An image receptor for thermal transfer recording, in which an image receiving layer is provided on a substrate coated with a smoothing layer. (2) For thermal transfer recording according to claim 1, wherein the smoothing layer is made of at least one inorganic material selected from clay, alumina, lyca, and zinc oxide and a binder. Image receptor. (3) Claim 1, characterized in that the smoothing layer is a layer containing at least one binder selected from carnano wax, wax, ester wax, and styrene butadiene lano wax. Image receptor 0 for thermal transfer recording described above (4) The smoothing layer is made of a layer containing at least one polymer selected from AkuIJ/pebolyestenopeacetate, polyethylene, styrene, polyamide, polysulfone, and polycarbonate. The image receptor for thermal transfer recording according to item 1.