JP2000168249A - Melt thermal transfer recording acceptive sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a melt thermal transfer recording acceptive sheet for obtaining a recording image of high quality having high sensitivity, ink transfer acceptivity, excellent fixability and high surface glossness and excellent image clarity. SOLUTION: The melt thermal transfer recording acceptive sheet comprises a sheet-like support, and an ink acceptive layer formed on the support in such a manner that the layer contains composite particles of at least one type of copolymer resin selected from an acrylic ester copolymer resin and an acrylic ester/styrene copolymer resin and colloidal silica, and a gloss value at an incident light receiving angle of 20 degrees based on JIS Z 8741 of a surface of the ink receptive layer is 40% or above.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a receiving sheet for fusing type thermal transfer recording used in copiers, printers, facsimile machines, etc. using a thermal fusing ink type thermal transfer recording system, and more particularly to ink receiving properties and dots in full color. The present invention relates to a fusion-type transfer sheet receiving sheet having excellent reproducibility, high sensitivity, excellent surface gloss, and high image quality.

[0002]

2. Description of the Related Art With the advance of OA in recent years, copiers, printers, facsimile machines, and the like utilizing various recording systems such as an electrophotographic system and a thermal transfer recording system have been widely used according to their respective applications. I have. Colored coloring materials are used for this image formation, and usually the coloring materials are melted, evaporated or sublimated and transferred onto a recording medium such as paper or a film sheet, and the recorded image is formed by adhesion, adsorption or dyeing action. It has gained.

[0003] In this type of recording method, a hot-melt ink type in which an ink ribbon or an ink sheet having a heat-meltable ink layer is melted by heat generated by a thermal head, and a color material is transferred to a recording medium to obtain a recorded image. Is characterized in that plain paper can be used as the receiving sheet.

[0004] In recent years, colorization of images together with high resolution,
Digitization has progressed, and high-definition images can be output in each recording method, and the texture of silver halide photographs with high clarity is demanded, and the images are reproduced by the ink jet recording method and the sublimation thermal transfer method.

On the other hand, the fusion type thermal transfer system is characterized in that plain paper can be used as a receiving sheet. However, in the case of color output, it is due to the smoothness of the surface of the ink receiving layer, the ink acceptability, the fixing property, and the like. However, there is a disadvantage that defects such as transfer unevenness and missing dots easily occur.

For this purpose, as a method for improving the surface smoothness of the receiving sheet for fusion-type thermal transfer recording, a specific range of smoothness can be imparted (Japanese Patent Laid-Open No. 60-110488),
A method of improving the ink receptivity by providing an ink receiving layer containing a specific pigment or binder (JP-A-60-11)
0489, JP-A-60-110490),
A method in which a hollow organic pigment or amorphous silica is contained in an ink receiving layer in order to enhance heat insulation and improve ink transferability (Japanese Patent Application Laid-Open No. 7-101170). It is already known to infiltrate. However, in these methods, the surface contains a specific pigment or has pores, so that the gloss of the white paper and the image area is low, and the gloss difference between the white paper area and the image area is large. Not been.

[0007]

The present invention relates to a receiving sheet for fusing type thermal transfer recording used in a fusing type thermal transfer recording system, which has high sensitivity, excellent ink transfer receptivity, and excellent fixability.
Provided is a receiving sheet for fusion-type thermal transfer recording capable of obtaining a high-quality recorded image having high surface gloss and excellent image clarity.

[0008]

Means for Solving the Problems The fusion type thermal transfer recording receiving sheet according to the present invention has a sheet-like support and an ink receiving layer formed thereon, and the ink receiving layer is
A surface of the ink-receiving layer, comprising composite particles of at least one copolymer resin selected from an acrylate-based copolymer resin and an acrylate / styrene-based copolymer resin, and colloidal silica; JIS
The glossiness at an incident / reception angle of 20 degrees based on Z8741 is 40% or more.

Further, in the receiving sheet for fusion-type thermal transfer recording according to the present invention, the composite particles have a particle diameter of 0.001 to 0.001.
0.1 μm, and the T
g is preferably from 0 to 90 ° C., and the composite particles are at least one copolymer resin selected from an acrylate copolymer resin and an acrylate / styrene copolymer resin. And the content ratio of colloidal silica to colloidal silica is preferably 30:70 to 70:30 (weight ratio). Further, it is preferable that the sheet-like support is formed by laminating a multilayer structure film on at least one of both surfaces selected from coated paper, synthetic paper and synthetic film.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION In order to improve the ink receptivity, it is necessary to improve the transferability and absorbency of the ink.
Ink transferability, besides the smoothness of the ink receiving layer surface,
The ink absorption depends mainly on the amount of voids on the surface of the ink receiving layer and the amount of oil absorbed by the pigment in the ink receiving layer. Therefore, in the conventional ink receiving layer, a pigment having a large particle diameter of 0.5 to 10 μm is used in order to increase the void amount, and the incident light is irregularly reflected on white paper or an image portion by unevenness of the surface, and the gloss is high. , The texture of a high gloss silver halide photograph cannot be obtained.

On the other hand, in order to obtain high surface gloss, it is necessary to provide an ink receiving layer on a sheet-like support having high smoothness and high surface gloss, and transfer the ink with a uniform film thickness on the ink receiving layer. However, when, for example, colloidal silica and polyvinyl alcohol which is a water-soluble polymer resin are used as the ink receiving layer, the white paper gloss is high, but the dots are thin,
The gradation reproducibility and dot reproducibility in the low gradation portion are poor. When latex is used as the water-dispersible polymer resin, since the dots are thick, the dots are crushed in a high gradation portion, the dot reproducibility is poor, and blocking is likely to occur.

The present inventors have studied diligently to obtain excellent dot reproducibility and high surface gloss, and have studied an acrylate copolymer resin and an acrylate / styrene copolymer resin with colloidal silica particles. An ink receiving layer containing a composite particle having a particle diameter of 0.001 to 0.1 μm which is strongly crosslinked between surfaces is provided, and the ink receiving layer has a white paper gloss of 40% or more at an incident / receiving angle of 20 degrees. Solved the above problems and completed the present invention.

If the particle size of the composite particles exceeds 0.1 μm, transparency may be inferior and the surface gloss may be reduced. On the other hand, if the particle size is less than 0.001 μm,
Complex production becomes difficult, and the voids between particles are small,
Ink acceptance may be poor. A more preferable range of the particle diameter of the composite particles is 0.01 to 0.1 μm.

If the Tg of the composite particles is less than 0 ° C., blocking may occur, and the composite particles may adhere to the ink ribbon and stain white paper. On the other hand, if the Tg is higher than 90 ° C., the adhesive strength may be weak. The preferred range of the Tg of the composite particles is from 20 to 80C.

The composite particles used in the present invention comprise at least one copolymer resin selected from an acrylate copolymer resin and an acrylate / styrene copolymer resin, and colloidal silica. The content ratio of
30: 70-70: 30 (weight ratio) is preferred. If the content of colloidal silica exceeds 70%, the adhesive strength to the sheet-like support may be poor, and the surface strength may be low. On the other hand, if it is less than 30%, the ink receptivity is poor, the ink overflows in the heavy color portion, and the transportability of the receiving sheet for fusion type thermal transfer recording in the printer may be reduced. A more preferable range of the content ratio of the copolymer resin and the colloidal silica is 40:60 to 60:40 (weight ratio).

Further, the composite particles of the present invention can be obtained by merely mixing colloidal silica and an acrylate-based copolymer resin or an acrylate / styrene-based copolymer resin so as to be contained in the ink receiving layer. Compared to the case of using the receiving layer, the amount of the acrylate-based copolymer resin or the acrylate / styrene-based copolymer resin used is larger, and the resin fills the gap between the particles, so that the ink receiving property is improved. Is poor, and ink overflow occurs in the heavy color portion, and the sensitivity is also lowered.

In the present invention, the ink receiving layer is preferably made of JIS
At an incident / reception angle of 20 degrees based on Z8741, the white paper gloss may be 40% or more, and the sheet-like support is not particularly limited, but those having high white paper gloss and small surface roughness are more preferable.

The material of the sheet-like support used in the present invention is manufactured from ordinary coated paper for printing such as gross art paper, coated paper and cast coated paper, laminated paper, polyethylene, polypropylene, polyethylene terephthalate and the like. Synthetic paper, nonwoven fabric, polycarbonate, polyphenylene sulfide, polyetherimide, polysulfone, polystyrene, nylon, cellulose diacetate, cellulose triacetate and other synthetic films,
Porous synthetic resin films such as expanded polyethylene terephthalate film and expanded polypropylene film,
Alternatively, those obtained by laminating these can be used depending on the application.

In addition to the colloidal silica and acrylate-based copolymer resin or acrylate / styrene-based copolymer resin of the composite particles, the ink-receiving layer may be made of a general material according to the quality target. Thermoplastic resins can be used in combination, for example, polyvinyl alcohol, isoprene, neoprene, polydienes such as polybutadiene, polybutene, polyisobutylene, polypropylene, polyalkenes such as polyethylene, vinyl halide, vinyl acetate, vinyl chloride-acrylonitrile, styrene , (Meth) acrylic acid, (meth) acrylic acid ester, (meth) acrylamide, vinyl copolymers such as methyl vinyl ether, polystyrene, styrene-butadiene, synthetic rubber latex such as methyl methacrylate-butadiene , Polyurethane resins, polyester resins, polyamide resins, olefin - maleic anhydride resins, such as synthetic polymer compounds such as melamine resin can be exemplified. One or more of these can be appropriately selected and used.

The amount of the thermoplastic resin is 100 parts by weight or less, more preferably 60 parts by weight or less, based on 100 parts by weight of the composite particles. If the compounding amount is more than 100 parts by weight, the voids between the particles are filled with the thermoplastic resin, so that the ink receptivity is poor and the ink may overflow in the heavy color portion.

The pigments that can be incorporated in the ink receiving layer include:
It is blended for the purpose of improving the heat insulating property of the ink receiving layer and the fixing property of the ink. Specifically, titanium dioxide, alumina, mineral pigments such as silica, polystyrene resin,
A solid type, hollow type or through-hole type organic pigment such as a vinylene chloride resin, a urea resin, a melamine resin, and an acrylic resin may be used alone or in combination. Further, the particle diameter of the pigment is preferably 1 μm or less so as not to affect transparency. The amount of the pigment is 100
It is preferably 100 parts by weight or less based on parts by weight. 1 pigment
When the amount is more than 00 parts by weight, not only the transparency of the ink receiving layer is impaired, but also the strength of the coating film is weak, and the coating film may peel off during recording.

In order to prevent the white paper portion of the receiving sheet for fusion type thermal transfer recording from being stained and to improve the transportability of the receiving sheet for fusion type thermal transfer recording in the printer, a release agent may be used, if necessary.
It is of course possible to use lubricants. Their use amount is at most 10 parts by weight, more preferably at most 5 parts by weight, based on 100 parts by weight of the composite particles.

In the coating liquid for the ink receiving layer, in addition to these, various auxiliaries, for example, a surfactant, a pH adjuster, a viscosity adjuster, a softener, a gloss imparting agent, a wax, a dispersant, and a flow modifier. , Anti-static agents, stabilizers, anti-static agents, cross-linking agents, sizing agents, optical brighteners, coloring agents, ultraviolet absorbers, defoamers,
Waterproofing agents, plasticizers, preservatives, fragrances, and the like can be used as needed.

The amount of the ink receiving layer to be applied is selected according to the intended use of the receiving sheet for fusing type thermal transfer recording of the present invention, but is generally sufficient to completely cover the fibers on the base paper surface. Is required, and the dry weight is 1 per side.
~30g / m ² is preferred. As a coating method for forming the ink receiving layer, generally known coating apparatuses, for example, a blade coater, an air knife coater, a roll coater, a reverse roll coater, a bar coater, a curtain coater, a die slot coater, a gravure coater, a champlex coater, Brush coater, two-roll or metering blade type size press coater, bill blade coater,
A short dwell coater, a gate roll coater or the like is appropriately used. These devices are used in a conventional manner as an on-machine coater or an off-machine coater.

In forming the ink receiving layer, the ink receiving layer may have a single-layer structure or, if necessary, a multilayer structure of two or more layers. In case of multi-layer structure,
Each coating liquid does not need to be the same, and may be appropriately adjusted and blended according to a required quality level, and is not particularly limited. It is also possible to provide a synthetic resin layer, a coating layer composed of a pigment and an adhesive, an antistatic layer, etc. on the back surface of the sheet-like support to provide curling prevention, printing suitability, paper feeding / dispensing suitability, and the like. is there. Further processing on the back of the sheet-like support, such as adhesion, magnetism, flame retardancy, heat resistance,
By performing post-processing such as water resistance, oil resistance, and anti-slip, it is of course possible to use it with additional applicability.

The receiving sheet for fusion type thermal transfer recording of the present invention has a water content of 3 to 1 after a usual drying step or before a surface treatment step.
Finished by adjusting to 0% by weight, preferably 4 to 8% by weight.

[0027]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but it is needless to say that the present invention is not limited to these ranges. In the examples, “parts” and “%” indicate “parts by weight of solid content” and “% by weight” unless otherwise specified.

Example 1 Coated paper (basis weight 104 g /
m ² ) on one side is a synthetic paper of 55 μm thickness (trademark: 260L)
LH, manufactured by Mobile Co., Ltd.) and a 60 μm-thick multilayered film (trade name: YUPO FPG) biaxially stretched on the opposite side of the coated paper with a polyolefin containing an inorganic pigment as a main component.
-60, manufactured by Oji Yuka Synthetic Paper Co., Ltd.) using a polyester-based adhesive and a dry-laminate method,
As the ink receiving layer, a particle size of colloidal silica and an acrylate / styrene copolymer resin having a particle diameter of 0.1 μm was used.
1 μm composite particles (trade name: Movinyl 8050, silica / resin = 60/40, Tg75 ° C .: manufactured by Hoechst Gosei Co.) were applied using a bar coater to a dry weight of 5 g / m ^2, and the moisture content was Is dried to 7%
An ink receiving layer was formed to obtain a receiving sheet for fusion type thermal transfer recording.

Example 2 A glossy surface of a commercially available synthetic paper (trade name: Yupoko GGF-130, basis weight 103 g / m ² , manufactured by Oji Oil Chemicals, Ltd.) was used as a sheet-like support. In the same manner as in Example 1 except that the ink receiving layer was provided, a receiving sheet for fusion-type thermal transfer recording was obtained.

Example 3 A commercially available cast paper (trade name: O) was used as a sheet-like support.
A melt-type thermal transfer recording receiving sheet was obtained in the same manner as in Example 2, except that K enamel coat, basis weight of 127.9 g / m ² : manufactured by Oji Paper) was used.

Example 4 As an ink receiving layer, composite particles of colloidal silica and an acrylate copolymer resin having a particle diameter of 0.1 μm (trade name: Movinyl 8030, silica / resin = 40/60, Tg22) C .: Hoechst Synthetic Co., Ltd.) was used in the same manner as in Example 2 to obtain a receiving sheet for fusion type thermal transfer recording.

Comparative Example 1 As the ink receiving layer, a particle size of colloidal silica and an acrylate / styrene copolymer resin having a particle diameter of 0.1 was used.
A fusion type thermal transfer recording receiving sheet was prepared in the same manner as in Example 2 except that 1 μm composite particles (trade name: LX-825D2, silica / resin = 10/90, Tg-15 ° C., manufactured by Hoechst Gosei Co., Ltd.) were used. Obtained. Blocking was observed in the receiving sheet for fusion-type thermal transfer recording, and the ink ribbon slightly adhered to the receiving sheet for fusion-type thermal transfer recording during printing, causing stains.

Comparative Example 2 Composite particles of colloidal silica and acrylate-based copolymer resin having a particle diameter of 0.1 μm (trade name: Movinyl 8025, silica / resin = 20/80, Tg24) were used as the ink receiving layer. C .: Hoechst Synthetic Co., Ltd.) was used in the same manner as in Example 2 to obtain a receiving sheet for fusion type thermal transfer recording. This receiving sheet for thermal transfer recording is
Overflowing of the ink was observed in the thick dot and the heavy color part.

Comparative Example 3 As an ink receiving layer, colloidal silica (trade name: ST)
-ZL, particle size 0.1 μm: 60 parts by weight, manufactured by Nissan Chemical Industries, Ltd., and an acrylate-based copolymer resin (trade name:
A melt-type thermal transfer recording receiving sheet was obtained in the same manner as in Example 2, except that 40 parts by weight of Movinyl 727, particle size 0.06 μm: manufactured by Hoechst Synthetic Co., Ltd. were mixed and stirred. Cracks were observed in this fusion type thermal transfer recording receiving sheet, and the glossiness of white paper was reduced. In the printed area, peeling of the coating film was partially observed.

Comparative Example 4 Colloidal silica (trade name: ST) was used as an ink receiving layer.
-ZL, 40 parts by weight of Nissan Chemical Industries, Ltd.) and 60 parts by weight of an acrylate-based copolymer resin (trade name: Movinyl 727, particle size 0.06 μm, manufactured by Hoechst Gosei Co., Ltd.) are mixed and stirred. A fusion type heat transfer recording receiving sheet was obtained in the same manner as in Example 2 except for the difference. In this fusion-type thermal transfer recording receiving sheet, ink overflow was observed in the heavy color portion.

Evaluation Method The receiving sheets for fusion-type thermal transfer recording obtained in the above Examples and Comparative Examples were each evaluated by the following methods, and the results are shown in Table 1. In the following evaluations, the ◎ or レ ベ ル level is suitable for practical use, but the △ or × level is not suitable for practical use.

[Evaluation of Dot Reproducibility of Recorded Image] Using the commercially available thermal transfer color printer (trade name: CH-7204, manufactured by Seiko Denshi Kogyo Co., Ltd.), full-color image recording was performed on the above-mentioned receiving sheet for melt-type thermal transfer recording. Measurement and quality evaluation were performed by the following methods, and the obtained results are shown in Table 1.

<Evaluation of Reproducibility of Dot on Recorded Image Surface> A single color (cyan) halftone dot portion and a single color (cyan) of the above recorded image
The magenta halftone dot printing is performed for the second color by superimposing the color image on the second color.
-3000), and the degree of dot omission and reproducibility (no thickening, thinning or chipping) was visually evaluated according to the following evaluation criteria. ：: There is no missing dot, and the reproducibility is extremely excellent. ：: There is almost no missing dots, and the reproducibility is good. Δ: There are considerable missing dots, and the reproducibility is poor. ×: Many dots are missing, and reproducibility is significantly poor.

<Evaluation of Sensitivity> As an evaluation of sensitivity, the low energy portion of an ink image formed at 12 gradations was magnified 30 times with a dot analyzer (DA-3000), and the degree of dot transfer was determined as follows. It was visually evaluated by reference. ：: There is no missing dot, and the reproducibility is extremely excellent. ：: There is almost no missing dots, and the reproducibility is good. Δ: There are considerable missing dots, and the reproducibility is poor. ×: Many dots are missing, and reproducibility is significantly poor.

<Evaluation of Surface Strength> As the evaluation of the surface strength, images formed on the white paper portion and the ink receiving layer were observed and evaluated according to the following criteria. ：: No peeling was observed in the image area. C: Fine cracks were observed in the blank area, and peeling was slightly observed in the image area. ×: Cracks are observed in the blank area, and peeling is clearly observed in the image area.

<Evaluation of Blocking> On a mirror-finished stainless steel plate (10 cm square), a receiving sheet for fusion type thermal transfer recording cut into a 10 cm square was placed so that the ink receiving layer and the back surface of the sheet-like support alternately contact each other. After 10 sheets are superimposed, 50 g / cm is applied to the receiving sheet for fusion type thermal transfer recording.
^A mirror-finished stainless steel plate (10 cm square) and a weight are placed so that a load of ² is applied, and the plate is held in this state at 50 ° C. in an environment of a relative humidity of 80% for 24 hours. The back surface was peeled off by hand, and the degree of peeling was evaluated according to the following criteria. ：: Peeled off without resistance, and the ink receiving layer was not affected at all. Δ: There is resistance, and the ink receiving layer is partially damaged. X: The state was as if glued, and the ink receiving layer was almost destroyed.

[0042]

[Table 1]

[0043]

As is clear from the examples, the receiving sheet for fusion-type thermal transfer recording according to the present invention has an ink receptivity,
It has excellent dot reproducibility, excellent white paper gloss and excellent print area gloss, and has the texture of silver halide photography, which greatly contributes to its industry.

 ──────────────────────────────────────────────────の Continued on the front page F term (reference) 2H111 AA26 CA03 CA12 CA13 CA23 CA25 CA30 CA31 CA33 4F100 AA00H AA20B AA20H AK01A AK01C AK03 AK12B AK12J AK25B AK25J AK41G AL01B AR00B AT00A BA10 BA10 BA10 BA10 BA10 BA10 BA10 BA10 BA10 BA10 JN21 YY00B

Claims (5)

[Claims] 1. A melt-type thermal transfer recording receiving sheet having a sheet-like support and an ink receiving layer formed thereon, wherein the ink receiving layer is made of an acrylate-based copolymer resin and an acrylate / polyester resin. It contains composite particles of at least one copolymer resin selected from styrene-based copolymer resins and colloidal silica, and has an incident / light-receiving angle of 20 degrees according to JIS Z8741 on the surface of the ink receiving layer. A glossy thermal transfer recording receiving sheet having a glossiness of 40% or more. 2. The composite particles having a particle diameter of 0.001
The receiving sheet according to claim 1, which has a thickness of from 0.1 to 0.1 µm. 3. The receiving sheet according to claim 1, wherein the composite particles have a Tg of 0 to 90 ° C. 4. The content ratio of the composite particles to at least one copolymer resin selected from an acrylate-based copolymer resin and an acrylate / styrene-based copolymer resin, and to colloidal silica. Is 30: 70-7
2. The receiving sheet for fusion-type thermal transfer recording according to claim 1, wherein the ratio is 0:30 (weight ratio). 5. The fusion-type thermal transfer recording according to claim 1, wherein the sheet-like support is formed by laminating a multilayer structure film on at least one of both surfaces selected from coated paper, synthetic paper and synthetic film. For receiving sheet.