JPH10100549A - Dye thermal transfer receiving sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a dyestuff thermal transcription acceptor sheet which is formed such that upon printing, an ink ribbon and the dyestuff thermal transcription acceptor sheet are easily separated from each other without any deterioration in picture quality, preventing any trouble in discharging acceptor sheet and any accident in cutting of a ribbon, prohibiting any possible wrinkling of the ribbon by allowing a slipping movement between the ink ribbon and the picture acceptor layer of the acceptor sheet. SOLUTION: A dyestuff thermal transcription acceptor sheet has a sheet-like support carrier and a picture acceptor layer for accepting a dyestuff formed on one surface of the carrier. After an ink ribbon is stacked on the picture acceptor layer to perform mat printing, a peeling force for the ink ribbon to peel off the dyestuff thermal transcription acceptor sheet for about 180 deg. is 20g/25mm or less, a coefficient of friction according to JISP 8147 between the picture acceptor layer and the ink surface of ink ribbon is 0.18 or more.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal dye transfer receiving sheet. More specifically, it is easy to peel off the ink ribbon and the dye thermal transfer receiving sheet after printing, and there is no trouble due to fusion such as deterioration of print image quality, defective discharge of the receiving sheet, cutting of the ink ribbon, and The present invention relates to a dye thermal transfer receiving sheet which does not wrinkle (ribbon wrinkling) of the ink ribbon due to slippage of the image receiving layer surface of the ink ribbon and the receiving sheet during printing.

[0002]

2. Description of the Related Art In recent years, the development of a color hard copy of a thermal transfer system, in particular, a sublimation type thermal transfer printer has been developed.
In a sublimation type thermal transfer printer, an ink ribbon including a sublimable dye layer of three colors (yellow, magenta, cyan) or four colors (yellow, magenta, cyan, black) is used.
By sequentially controlling and heating the heating energy of the thermal head in order to change the transfer amount of the dye of each color, it is possible to transfer and form a full-color image of density gradation. Such a thermal transfer printer is rapidly spreading even in ordinary households for applications such as printing a picture taken by a television image or a video camera on a postcard or printing on a sticker.

A dye thermal transfer receiving sheet (hereinafter, abbreviated as a receiving sheet) used in such a printer has an image receiving layer for receiving a sublimable dye on one surface of a sheet-like support. In general, on the back surface of the receiving sheet (the side opposite to the surface on which the image receiving layer is provided), (1) prevention of poor running performance due to static electricity, (2) prevention of dust and dust suction due to generation of static electricity, (3) A back coating layer is provided for the purpose of reducing the coefficient of friction between receiving sheets and the like.

[0004] In such a receiving sheet, at the time of printing, the binder resin of the ink ribbon adheres to the surface of the receiving layer of the receiving sheet, and the binder resin of the ink ribbon peels off from the ink ribbon substrate. A phenomenon of transferring to the layer surface (hereinafter, abbreviated as fusion) may occur. When such fusion occurs, not only does the quality of the printed image deteriorate, but also, in particular, after the binder resin of the ink sheet adheres to the receiving layer surface, the binder resin peels off from both the ink ribbon substrate and the receiving layer surface. If not, there is a problem that the receiving sheet is not ejected and becomes jammed in the printer due to being pulled by the ink ribbon, or the ink ribbon is cut even if the receiving sheet is ejected.

For the purpose of preventing such fusion, attempts have been made to add a release agent to the image-receiving layer, such as a polyester-modified silicone resin contained in the image-receiving layer (JP-A-4-126291). However, if the added amount of the release agent is increased, the ink ribbon and the image receiving layer surface slip during printing, causing a problem that wrinkles of the ink ribbon occur in a printed image (hereinafter, abbreviated as ribbon wrinkles). I will.

[0006]

According to the present invention, the ink ribbon and the receiving sheet can be easily separated after printing,
No troubles due to fusion such as deterioration of the print image quality, defective discharge of the receiving sheet, cutting of the ink ribbon, and wrinkling of the ink ribbon due to slippage of the ink ribbon and the image receiving layer surface of the receiving sheet during printing. It is intended to provide a receiving sheet which does not generate (ribbon wrinkle).

[0007]

Means for Solving the Problems The inventors of the present invention have proposed a method of receiving solid printing on a receiving sheet, such as solid printing of a single-color ribbon, solid printing of a three-color ribbon, or solid printing of a four-color ribbon. It has been found that the above problem can be solved by specifying the peeling force between the sheet and the ink ribbon and setting the friction coefficient between the image receiving layer surface and the ink surface of the ink ribbon according to JIS P 8147 in a specific range. It is.

That is, according to the present invention, in a dye thermal transfer receiving sheet having a sheet-like support and an image receiving layer for receiving a dye formed on one surface of the support, an ink ribbon is superposed on the image receiving layer surface. After the solid printing, the peeling force (measured at a peeling speed of 500 mm / min) when the dye thermal transfer receiving sheet and the ink ribbon were peeled at 180 ° was 20 g /.
A dye thermal transfer receiving sheet having a thickness of 25 mm or less and a friction coefficient between the image receiving layer surface and the ink surface of the ink ribbon described in JIS P 8147 of 0.18 or more.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The receiving sheet of the present invention has a 180 ° peeling force of 20 g / 25 mm or less between the ink ribbon and the receiving sheet measured at a speed of 500 mm / min. JIS with ink surface
It is necessary to satisfy two conditions of a friction coefficient described in P 8147 of 0.18 or more. Ink ribbon and receiving sheet 1
By setting the 80 ° peeling force to 20 g / 25 mm or less, the printed ink ribbon and the receiving sheet can be easily peeled off, so that no fusion occurs, and the quality of the printed image is reduced.
It is possible to prevent occurrence of troubles such as defective paper discharge and cutting of the ink ribbon. In addition, by setting the friction coefficient between the image receiving layer surface and the ink surface of the ink ribbon to 0.18 or more according to JIS P8147, the ink ribbon and the image receiving layer surface do not slip during printing, and ink ribbon wrinkles are prevented. A receiving sheet that does not form.

As a specific method for controlling the 180 ° peeling force between the ink ribbon and the receiving sheet (hereinafter abbreviated as ribbon peeling force), (1) a dye-dyeing resin having a different Tg (glass transition temperature) is used. (2) adding a crosslinking agent to the image receiving layer, (3) adding a release agent to the image receiving layer, and the like. Regarding (1), it is possible to improve the fusion by increasing the Tg of the dye-dyeable resin.
On the contrary, there is a problem that the print sensitivity is lowered.
Similarly, for (2), if the amount of the crosslinking agent added is too large,
Even if the fusion can be improved, the printing sensitivity is lowered. On the other hand, in the method (3), if the amount of the release agent added is too large, the coefficient of friction between the ink ribbon and the image receiving layer decreases, and ribbon wrinkling occurs. Therefore, in order to prevent the occurrence of fusing and to prevent the adverse effects such as a decrease in print sensitivity and ribbon wrinkles, (1)
By combining the three methods (2) and (3), the above condition must be satisfied. However, by combining the two methods (2) and (3) from the viewpoint of ease of control,
It is practical to control the ribbon release force and the coefficient of friction between the ink ribbon and the image receiving layer.

In the receiving sheet of the present invention, the image receiving layer is formed mainly of a dyeing resin capable of dyeing a sublimable dye transferred from an ink ribbon. Examples of such a dyeing resin include a polyester resin, a vinyl chloride-vinyl acetate copolymer resin, a polycarbonate resin, an acrylic resin, and a cellulose derivative. The coating amount of the image receiving layer is preferably from ¹ to 12 g / m ² ,
More preferably, it is 3 to 10 g / m ² . 1g coating amount
If it is less than / m ² , defects such as deterioration of image quality and decrease in gloss of a printed surface may occur. Also, 12g
/ M ² , the effect is saturated and uneconomical,
The print density may decrease.

As described above, a crosslinking agent, a release agent, and the like are added to the image receiving layer of the receiving sheet of the present invention for the purpose of preventing fusion with the ink ribbon. As a cross-linking agent, isocyanate is generally used, and as a releasing agent, a wax can be used in addition to a silicone oil and a silicone resin. If necessary, a fluorescent dye, a plasticizer, an antioxidant, a pigment, an ultraviolet absorber and the like may be added to the receiving layer. These additives may be mixed with the main component of the receiving layer and applied, or may be applied as a separate coating layer above and / or below the receiving layer. As the pigment, a silica pigment, a titanium pigment, a clay, a plastic pigment, or the like can be used. Among them, silica pigments are preferably used in terms of whiteness and image quality, and the average particle diameter thereof is preferably about 1 to 12 μm.
About 2 to 15 parts by weight with respect to 0 parts by weight is appropriate.

A back coating layer may be provided on the back of the receiving sheet of the present invention. The backside coating layer is mainly composed of an adhesive resin, and may be added with a conductive agent, a slipping agent, and a pigment, if necessary, and prevents block transfer of the ink ribbon even if the front and back are mistaken. An anti-fusing agent may be added for the purpose. As the adhesive resin, a known polymer binder can be arbitrarily selected and used, and an acrylic emulsion, an acrylic resin, a polyester resin, a polyurethane resin, a styrene-butadiene copolymer latex, polyvinyl alcohol, starch, Examples thereof include ammonium styrene maleate and the like. As the conductive agent, a commercially available antistatic agent can be used, and an electron conductive inorganic fine powder obtained by mixing a fine powder such as titanium oxide or zinc oxide with an impurity and firing to increase the electron conductivity can be used. Commercially available waxes, silicone resins and the like can be used as the slip agent and the anti-fusing agent. As the pigment, silica pigment, clay, titanium oxide, calcium carbonate, barium sulfate and the like can be used. The coating amount of the back coating layer is not particularly limited, but is preferably in the range of 0.1 to 10 g / m ² . If the amount is too small, the effect will not be exhibited, and if it is more than that, no further effect can be expected,
Increases cost and is not practical.

Further, when the receiving sheet travels in the printer, a traveling trouble due to static electricity is prevented.
Another conductive layer different from the back coating layer can be applied on the receiving layer surface of the receiving sheet or between the receiving layer and the sheet-like support.

Examples of the sheet-like support used in the present invention include a paper base such as coated paper, art paper and woodfree paper, a laminated paper obtained by laminating a resin such as polyethylene on a paper base,
Examples thereof include a film of polyester, nylon, or polyolefin (for example, polypropylene), or a biaxially stretched film having voids and a multilayer structure containing a polyolefin resin and an inorganic pigment as main components. Furthermore, not only the above-mentioned materials can be used alone, but also those having a multilayer structure formed by laminating two or more of the above-mentioned materials by a dry lamination method or the like can be used, and the combination is not limited.

The thickness of the sheet-like support is 100 to 300 μm.
m is preferred. When the thickness is less than 100 μm, the mechanical strength becomes insufficient, and the rigidity of the receiving sheet obtained therefrom and the repulsive force against deformation become insufficient. It cannot be prevented. On the other hand, when the thickness exceeds 300 μm, the thickness of the obtained receiving sheet becomes excessive. For a printer of a given volume,
There is a limit to the capacity of the receiving sheet, and an excessive thickness causes a decrease in the number of receiving sheets or increases the volume of the printer, making it difficult to make the printer compact.

The receiving layer, the back coating layer and the other coating layer of the receiving sheet of the present invention can be formed by coating and drying with a known coater such as a bar coater, a gravure coater or an air knife coater.

[0018]

The present invention will be described in detail with reference to the following examples, but the scope of the present invention is not limited to these examples.
In Examples, “%” and “parts” all indicate “% by weight” and “parts” unless otherwise specified.

Example 1 Polyethylene terephthalate (PET) having a thickness of 50 μm
On both sides of the film, a 60 μm-thick multi-layer film biaxially stretched with a polyolefin containing an inorganic pigment as a main component (trade name: Yupo FPG60, manufactured by Oji Oil Chemicals, Ltd.)
Were laminated by a dry lamination method using a polyester-based adhesive to form a sheet-like support. On one surface, a coating solution for an image receiving layer having the following composition was solidified at 8 g / m ^2.
At a rate of 1% by a die coating method and dried to form a dye image receiving layer. Further, on the other surface, a coating solution for a back coating layer having the following composition was applied by a bar coating method at a solid content of 1 g / m ² and dried at 120 ° C. for 2 minutes to form a back coating layer. .

[Coating Solution for Image Receiving Layer] Component Parts by weight Saturated polyester resin (trade name: Byron 200, manufactured by Toyobo) 100 parts Silicone resin (trade name: SH3746, manufactured by Toray Dow Corning Silicone) 3 parts Isocyanate (trade name) : Coronate HX, Nippon Polyurethane) 8 parts Toluene / methyl ethyl ketone = 5/1 mixed solvent 600 parts

[Coating Liquid for Back Coating Layer] Ingredients Parts by weight Acrylic emulsion (trade name: A-106, manufactured by Toa Gosei Chemical) 100 parts Antistatic agent (trade name: Chemistat 6120, manufactured by Sanyo Chemical) 5 parts Water 900 copies

Example 2 A receiving sheet was obtained in the same manner as in Example 1. However, an image receiving layer was formed using the following coating liquid. [Coating solution for image-receiving layer] Component Weight part Saturated polyester resin (trade name: Byron 200, manufactured by Toyobo) 100 parts Silicone resin (trade name: SH3746, manufactured by Toray Dow Corning Silicone) 2 parts Isocyanate (trade name: Coronate HX) 8 parts Toluene / methyl ethyl ketone = 5/1 mixed solvent 600 parts

Comparative Example 1 A receiving sheet was obtained in the same manner as in Example 1. However, an image receiving layer was formed using the following coating liquid. [Coating solution for image receiving layer] Component Weight part Saturated polyester resin (trade name: Byron 200, manufactured by Toyobo) 100 parts Silicone resin (trade name: SH3746, manufactured by Toray Dow Corning Silicone) 1 part Isocyanate (trade name: Coronate HX) 8 parts Toluene / methyl ethyl ketone = 5/1 mixed solvent 600 parts

Comparative Example 2 A receiving sheet was obtained in the same manner as in Example 1. However, an image receiving layer was formed using the following coating liquid. [Coating solution for image receiving layer] Component Weight part Saturated polyester resin (trade name: Byron 200, manufactured by Toyobo) 100 parts Silicone resin (trade name: SH3746, manufactured by Toray Dow Corning Silicone) 3 parts Isocyanate (trade name: Coronate HX) 5 parts toluene / methyl ethyl ketone = 5/1 mixed solvent 600 parts

Comparative Example 3 A receiving sheet was obtained in the same manner as in Example 1. However, an image receiving layer was formed using the following coating liquid. [Coating solution for image receiving layer] Component Weight part Saturated polyester resin (trade name: Byron 200, manufactured by Toyobo) 100 parts Silicone resin (trade name: SH3746, manufactured by Toray Dow Corning Silicone) 5 parts Isocyanate (trade name: Coronate HX, 8 parts toluene / methyl ethyl ketone = 5/1 mixed solvent 600 parts

Comparative Example 4 A receiving sheet was obtained in the same manner as in Example 1. However, an image receiving layer was formed using the following coating liquid. [Coating solution for image-receiving layer] Component Weight part Saturated polyester resin (trade name: Byron 200, manufactured by Toyobo) 100 parts Silicone resin (trade name: SH3746, manufactured by Toray Dow Corning Silicone) 2 parts Isocyanate (trade name: Coronate HX, Japan) Polyurethane) 10 parts Toluene / methyl ethyl ketone = 5/1 mixed solvent 600 parts

"Evaluation method" The following evaluation was performed on the obtained receiving sheet, and the results are shown in Table 1. (1) Ribbon peeling force A thermal head printing device (trade name: TH-PMD, manufactured by Okura Electric Co., Ltd.)
A commercially available three-color ink ribbon for a sublimation thermal transfer printer (trade name: JX-75R3, manufactured by Sharp) is printed solidly in the order of yellow, magenta, and cyan under the conditions of a printing voltage of 10.5 V. The 180 ° peeling force was measured with a tensile tester (trade name: Strograph-M2, manufactured by Toyo Seiki) under the condition of a peeling speed of 500 mm / min.

(2) Coefficient of friction between ink ribbon and receiving layer surface The friction coefficient between the receiving layer surface of the receiving sheet and a commercially available three-color ink ribbon for a sublimation thermal transfer printer (trade name: JX-75R3, manufactured by Sharp) is defined in JIS P8147. It measured according to.

(3) Evaluation of fusion bonding A commercially available sublimation thermal transfer printer (trade name: J
X-7500 (manufactured by Sharp)), solid printing was performed with a three-color ink ribbon (trade name: JX-75R3, manufactured by Sharp), and the presence or absence of fusion was evaluated in the following three grades. 1: No fusing 2: The fusing and the quality of the printed image is degraded 3: The fusing and the ink ribbon are stuck and the paper is not discharged,
Or the ink ribbon is cut

(4) A commercially available sublimation heat transfer printer (trade name: J
X-7500, manufactured by Sharp) using a three-color ink ribbon (trade name: JX-75R3, manufactured by Sharp).
Solid printing was performed in each of the single colors of magenta and cyan, and it was visually determined whether or not the printed image had wrinkles of the ink ribbon.

(5) Print Sensitivity A commercially available sublimation thermal transfer printer (trade name: J
X-7500, manufactured by Sharp Corporation), and the highest density portion was measured using a Macbeth densitometer.

[0032]

[Table 1]

[0033]

According to the dye thermal transfer receiving sheet of the present invention, the ink ribbon and the receiving sheet can be easily peeled off after printing, and the quality of the printed image deteriorates, the discharge of the receiving sheet fails, and the like.
It has no practical problems due to fusion such as cutting of the ink ribbon and no wrinkling of the ribbon, and has high practical value.

Claims (1)

[Claims] 1. A dye thermal transfer receiving sheet having a sheet-like support and an image-receiving layer for receiving a dye formed on one surface of the support, and an ink ribbon is superimposed on the image-receiving layer to perform solid printing. Thereafter, the peeling force (measured at a peeling speed of 500 mm / min) when the dye thermal transfer receiving sheet and the ink ribbon are peeled at 180 ° is 20 g / 25 mm or less, and JISP 8147 between the image receiving layer surface and the ink surface of the ink ribbon. A dye thermal transfer receiving sheet having a friction coefficient of 0.18 or more.