JP2001063230A - Thermal transfer material and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thermal transfer material capable of forming a high quality image which is free from an image defect without generating any flaw in an image forming region even when the material is wound up in a rolled state. SOLUTION: For a thermal transfer material wherein image forming regions of respective hues of cyan, magenta, yellow and black are successively solid- printed on a substrate parallel to a conveying direction of the substrate, an average ink transfer amount in a 0.5-5 mm region toward outside the image forming region from a tip part in the conveying direction of the image forming region wherein ink is transferred, is 5-90% of the ink amount in an image forming region corresponding to the same area as the region. A thermal transfer material is manufactured wherein a printing intaglio in which an average cell volume of a surface of a printing intaglio of 0.5-5 mm region toward outside the print part from the tip part of the print part of the printing intaglio is 5-90% of the cell volume of the print part corresponding to the same area as the region.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer material to be transferred by applying heat and a method of manufacturing the same, and more particularly, to a thermal transfer material capable of forming an image by thermal transfer using a heating device such as a thermal head based on a digital image signal. It relates to the manufacturing method.

[0002]

2. Description of the Related Art Conventionally, various transfer systems such as a sublimation dye transfer system, a hot-melt heat transfer system, and a thin film transfer system have been adopted for printers and word processors that output images and the like. Generally, a thermal transfer material in which an ink layer such as a sublimation dye layer is provided on one surface of a base film is used. In the formation of a full-color image using the above-described thermal transfer material, heat is applied from the surface (back surface) of the thermal transfer material on the side where the image-forming layer is not provided, using a heating device such as a thermal head. The transfer is performed by transferring dots of three or four colors onto the transfer target.

[0003] The formed image is clear and excellent in transparency because the dye used is a dye, has high reproducibility of intermediate colors and image gradation, and has high image quality equivalent to that of a conventional full-color photographic image. Can be formed.

As described above, a thermal transfer material used for thermal transfer is prepared by dissolving and dispersing a sublimable dye, pigment, or the like in a vehicle on one surface of a heat-resistant long base film by multicolor rotogravure printing. It is formed by transferring (printing) and processing the applied ink at high speed. In order to form a high quality image by transferring with this thermal transfer material, predetermined colors are
It must be printed at a predetermined position. In the gravure rotary printing, a plurality of gravure plates corresponding to each color are arranged, and the gravure plates rotate at the same speed while being in contact with the base film, and the transfer of the base material onto the base film serving as a support of the thermal transfer material. In parallel with the direction, inks of respective colors of cyan, magenta, yellow, and black are sequentially and continuously printed in a predetermined pattern at predetermined intervals. Since the gravure plate used for printing has concave cells having a certain cell volume in the printed portion, the printing area corresponding to the printed portion, on which the ink on the base film has been transferred, that is, thermal transfer In an area where an image can be formed at the time of thermal transfer as a material (image forming area), an ink layer having a substantially uniform thickness is formed. After printing (after formation of the image forming area), when dried, it is wound up in a roll form and stored for a certain period of time. In the roll state, it is difficult to wind up the image forming areas provided on the base material so as to overlap each other neatly. Therefore, the peripheral edge (edge part) of the image forming area is overlaid on the upper and lower portions. At an arbitrary position in the image forming area.

[0005] As described above, when the edge portion of the image forming area is wound in a roll shape while being located in the other image forming area and stored for a long period of time, the edge in the other image forming area may be wound. In the section, an image defect occurs when an image is formed with uneven density.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional problems and achieve the following objects. That is, the present invention can form a high-quality image without image defects such as density unevenness without causing defects in the image forming area even when the thermal transfer material on which the image forming area is formed is wound into a roll. It is an object to provide a thermal transfer material.

[0007]

Means for solving the above problems are as follows. That is, <1> a thermal transfer material in which image forming regions of cyan, magenta, yellow, and black hues are successively solid printed on the support in parallel with the transport direction of the support, and the ink is transferred. The average ink transfer amount in a region of 0.5 to 5 mm from the leading end in the conveyance direction of the image forming region toward the outside of the image forming region is 5 to 5 of the ink amount in the image forming region corresponding to the same area as the region. It is a thermal transfer material characterized by 90%.

<2> The average ink transfer amount in the area of 0.5 to 5 mm from the end of the image forming area to which the ink has been transferred in the transport direction toward the outside of the image forming area corresponds to the same area as the area. The thermal transfer material according to <1>, wherein the amount of the ink in the image forming area is 5 to 90%.

<3> Printing is performed so that the amount of ink in the area of 0.5 to 5 mm continuously and gradually decreases from the leading end and / or the trailing end of the image forming area toward the outside of the image forming area. <1> or <2>.

<4> Each area of 0.5 to 5 mm from the leading end and / or the trailing end of the image forming area in the transport direction to the outside of the image forming area is printed with a constant ink amount. A thermal transfer material according to <1> or <2>. <5> The thermal transfer material according to any one of <1> to <4>, wherein the image forming region contains at least a pigment and an amorphous organic high molecular polymer.

<6> In a method for manufacturing a thermal transfer material, in which image forming areas of cyan, magenta, yellow, and black hues are successively solid printed on the support in parallel with the direction of transport of the support, Average cell volume on the surface of the printing intaglio in a region of 0.5 to 5 mm from the front end of the printing intaglio printing portion corresponding to the transfer direction front end of the transferred image forming area toward the outside of the printing portion. Is 5 to 5 of the cell volume of the printed portion corresponding to the same area as the region.
A method for producing a thermal transfer material, wherein the thermal transfer material is printed by 90% of an intaglio printing plate.

<7> 0.5 to 5 mm from the end of the printing portion of the intaglio printing for printing corresponding to the end in the transport direction of the image forming area to which the ink has been transferred, toward the outside of the printing portion.
The average cell volume on the surface of the intaglio printing for printing in the region is 5% of the cell volume of the printing portion corresponding to the same area as the region.
<6> to be printed by an intaglio printing for printing which is 〜90%.
3. The method for producing a thermal transfer material according to (1).

<8> From the leading end and / or the trailing end of the printing portion of the printing intaglio to the outside of the printing portion, 0.5-0.5.
The method for producing a thermal transfer material according to <6> or <7>, wherein cells having a cell volume continuously decreasing are arranged on the surface of the intaglio printing plate having a region of 5 mm.

<9> From the leading end and / or the trailing end of the printing portion of the intaglio printing plate to the outside of the printing portion, 0.5-0.5.
The method for producing a thermal transfer material according to <6> or <7>, wherein cells having a fixed cell volume are arranged on the surface of the intaglio printing plate having a region of 5 mm.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The thermal transfer material of the present invention has image forming areas of cyan, magenta, yellow, and black hues formed on a support at regular intervals so as to be parallel to the transport direction of the support. The average ink transfer amount of the area of 0.5 to 5 mm from the leading end of the image forming area to which the ink is transferred in the conveying direction toward the outside of the image forming area. The ink amount is 5 to 90% of the ink amount in the image forming area corresponding to the same area. In the method for producing a thermal transfer material of the present invention, from the front end of the printing portion of the intaglio printing for printing corresponding to the front end in the transport direction of the image forming area to which the ink has been transferred, 0.5 to 0.5 to the outside of the printing portion. The support is obtained by printing using a printing intaglio in which the average cell volume on the surface of the printing intaglio in an area up to 5 mm is 5 to 90% of the cell volume of the printing portion corresponding to the same area as the area. An image forming area is provided above. Hereinafter, the thermal transfer material of the present invention will be described, and together with the description, the thermal transfer image receiving material and thermal transfer recording method used together with thermal transfer recording will be clarified.

<Thermal Transfer Material> The thermal transfer material of the present invention has a function of forming an image on a thermal transfer image receiving material described later by thermal transfer, and uses a long support for the production of the thermal transfer material. Cyan, magenta, yellow, and the like having a certain pattern shape on the support in parallel with the transport direction of the support, that is, along the long (length) direction.
The image forming areas of the respective colors of black are solid-printed in order at a certain interval. For example, in the thermal transfer material of the present invention, as shown in FIG. 1A, an image forming area 3 is provided on a support 2, and a leading end 3p and a terminating end 3p of the image forming area 3 in the transport direction Q of the image forming area 3. In the embodiment having a leading end ink region 4 and a trailing end ink region 5 in the 'to P or P' direction, and further having a back layer 10 on the surface of the support 2 on the side where the image forming region is not provided. There may be. In the present invention, it is not always necessary to provide both the leading end ink region 4 and the trailing end ink region 5 as described above, and it is sufficient that at least the leading end ink region is provided. But,
In terms of the effect, a mode in which the terminal ink region is provided is preferable.

-Image Forming Area- The image forming area is a region where an image can be formed by thermal transfer onto a transfer target, that is, an ink layer containing a colorant, and is formed on a long support. At least solid image forming areas of each color of cyan, magenta, and yellow are sequentially printed with a fixed interval, and, for example, as shown in FIG. Y (yellow), M (magenta), C (cyan), K
(Black) image forming areas of each color are sequentially arranged at a constant interval S
, And may be configured to be repeatedly and continuously printed. A leading end ink region 4 and a trailing end ink region 5 are provided within an interval S between the image forming regions. still,
The arrangement order of the image forming areas of the respective colors is not limited to the order shown in FIG. FIG. 4 is a diagram showing an example of the configuration of the thermal transfer material of the present invention. The image forming region includes at least a pigment as a colorant and an amorphous organic high molecular polymer.

In the thermal transfer material of the present invention, the image forming areas of each hue having a predetermined pattern are continuously arranged at a constant interval in the longitudinal direction of the long support. And the distance from the leading end of the image forming area in the conveying direction to the outside of the image forming area.
An ink layer having an average ink transfer amount smaller than the ink amount in the image forming region is provided in a region of 5 to 5 mm (hereinafter, sometimes referred to as a “tip ink region”).
Specifically, the average ink transfer amount is set at 0.1 from the leading end of the image forming area in the transport direction to the outside of the image forming area.
The amount of ink is 5 to 90% of the ink amount in the image forming area, which corresponds to the same area as the area up to 5 to 5 mm (tip ink area).

An ink layer in which the average ink transfer amount in the tip ink region is smaller than the ink amount in the image forming region is as follows:
An area of 0.5 to 5 mm from the end of the image forming area in the conveying direction as well as the end of the image forming area in the conveying direction toward the outside of the image forming area (hereinafter referred to as “end ink area”).
There is that. ) Is preferably provided in the same manner. The preferred average ink transfer amount is the same as in the case of the tip ink region. At the end of the image forming area in the transport direction, similarly to the front end, the edge of the peripheral end of the image forming area may similarly cause local pressing, thereby causing linear density unevenness along the edge line. Therefore, by providing both at the leading end and the trailing end of the image forming area,
Higher quality images can be stably obtained.

If the average amount of ink is less than 5% of the amount of ink in the image forming area, the step of the edge tone at the peripheral end of the peripheral part of the image forming area may not be sufficiently mitigated. If it exceeds, the height may be the same as that of the image forming area, and a sufficient effect may not be obtained. If the distance is less than 0.5 mm from the leading end or the trailing end in the transport direction to the outside of the image forming area, the step at the edge may not be sufficiently mitigated. Ink layers may overlap with each other, resulting in color mixing.

The average ink transfer amount is an average ink amount of the entire leading end ink region or the end ink region.
If the average ink transfer amount is in the above range, any ink amount distribution may be provided in the region of the leading end ink region or the terminal end ink region. It may be. Figure 1
FIG. 3A is a schematic cross-sectional view illustrating a state in which the amount of ink continuously and gradually decreases from a leading end and a trailing end of the image forming area toward the outside of the image forming area. FIG.
FIG. 3A is a schematic cross-sectional view for explaining how the amount of ink gradually decreases from the leading end and the trailing end of the image forming area toward the outside of the image forming area. FIG.
-(A) is thinner than the image forming area from the leading end and the end in the conveying direction of the image forming area to the outside of the image forming area,
FIG. 4 is a schematic cross-sectional view for explaining a state in which an ink layer having a uniform amount of ink is formed.

That is, as shown in FIG. 1A, the amount of ink in the leading end ink region 4 or the trailing end ink region 5 is from the leading end or the trailing end of the image forming region 3 in the transport direction to the outside of the image forming region. A mode in which the film thickness is gradually reduced gradually and continuously in the P or P ′ direction, and as shown in FIG. It is also possible to adopt a mode in which the amount of ink decreases stepwise and the film thickness changes stepwise. Further, as shown in FIG. 3A, an embodiment having a uniform film thickness which is thinner than the image forming area and has almost no ink amount distribution may be adopted, or other embodiments may be adopted. Good.

Therefore, in the case where the ink gradually decreases or changes stepwise as described above, the leading ink region and the trailing ink region have a predetermined amount of ink necessary for image formation. It may be configured to have a portion having the same ink amount as that of the image forming area, that is, 100% of the ink amount of the image forming area. Further, in a mode in which the film thickness is gradually reduced from the leading end or the end in the conveyance direction of the image forming area toward the outside of the image forming area and the film thickness is gradually reduced, the gradual decrease is linear, concave curved, It may have any shape of a convex curve.

As shown in FIG. 1, the leading end and the trailing end of the image forming area in the conveying direction correspond to the conveying direction Q of the support conveyed when the image forming area is formed on the support 2. One end 3p of the image forming area on the transport direction Q side of the single image forming area 3 among a plurality of image forming areas provided along the length (direction) in parallel, This refers to the other end 3p 'that faces.

Usually, when an image forming area is provided on a support, it is necessary to keep the amount of ink in the area uniform from the viewpoint of forming an image having a stable image density without density fluctuation. At the peripheral end, there is a step with an edge tone between the support and the support. When rolled up in a roll shape, a locally higher pressure is applied at the step portion of the edge tone, and the image forming area located at that portion is transferred to the support overlaid thereon, and the edge is transferred to the edge. The density decreases along the line, and as a result, an image having linear density unevenness is formed when the image is formed. However, as described above, by providing the leading end ink region or the leading end ink region and the trailing end ink region at the peripheral end of the image forming region provided on the support, the step of the edge tone with the support is reduced. As a result, it is possible to prevent a decrease in density due to the transfer to the support superposed on the upper portion.

The pigment contained in the ink layer in the image forming area is generally classified into an organic pigment and an inorganic pigment. The former is particularly excellent in the transparency of the coating film, and the latter is generally excellent in the concealing property. When the thermal transfer material of the present invention is used for printing color proofing, an organic pigment that matches or has a similar color tone to yellow, magenta, cyan, and black generally used for printing inks is preferably used. In addition, a metal powder, a fluorescent pigment, or the like may be used. Among the above, for example, azo pigments, phthalocyanine pigments, quinacridone pigments, thioindigo pigments, anthraquinone pigments,
Preferred are isoindolinone pigments, carbon black and the like. These pigments may be used alone or in combination of two or more, and may be used in combination with known dyes for the purpose of adjusting hue.

The average particle size of the pigment is from 0.03 to
1 μm is preferable, and 0.05 to 0.5 is more preferable.
If the particle size is less than 0.03 μm, the dispersion may cause gelation, and if it exceeds 1 μm, coarse particles in the pigment may hinder the adhesion between the thermal transfer layer and the image receiving layer. There is.

Examples of the amorphous organic high molecular polymer contained in the image forming layer include those having a softening point of 50 to 150 ° C., for example, butyral resin, polyamide resin, polyethyleneimine resin, sulfonamide resin, polyester Styrene such as polyol resin, petroleum resin, styrene, α-methylstyrene, 2-methylstyrene, chlorostyrene, vinylbenzoic acid, sodium vinylbenzenesulfonate, aminostyrene and derivatives thereof, homopolymers and copolymers of substituted derivatives , Methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, butyl methacrylate, hydroxyethyl methacrylate and methacrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, acrylic acid esters such as α-ethylhexyl acrylate and Dienes such as acrylic acid, butadiene, isodiene, isoprene, acrylonitrile, vinyl ethers, maleic acid and maleic esters, maleic anhydride, cinnamic acid, vinyl chloride, vinyl acetate and other vinyl monomers alone or in others And a copolymer with a monomer or the like. These resins can be used as a mixture of two or more kinds.

Of the above, butyral resin, styrene /
Maleic acid half ester resins and the like are preferred. As described above, the softening point of the resin is preferably 50 to 150 ° C., and if the softening point exceeds 150 ° C., the sensitivity at the time of thermal transfer may decrease. The adhesion resistance of the region may be reduced.

In the present invention, an image forming area is formed by placing an ink for an image forming area prepared in a coating liquid state on a gravure plate, transferring the ink continuously to a support by high-speed rotary printing, and drying. The content of the pigment in the ink for the image forming area is preferably 30% based on the total solid weight in the ink from the viewpoint of obtaining a desired optical density in a thin film.
Similarly, the content of the amorphous organic high-molecular polymer is preferably 25 to 60% by weight based on the total solid content in the ink. Further, the content of the pigment with respect to the amorphous organic high molecular polymer is preferably 5 to 90% by weight based on the weight of the binder.

Further, in the ink for an image forming area containing a pigment, the content of the pigment particles having a particle size of 1 μm or more is determined by:
It is preferable that the content be 30% by weight or less based on the total solid content. If the content of the pigment particles having a size of 1 μm or more exceeds 30% by weight, the transparency of a region where a plurality of colors overlap may be reduced or the gradation reproducibility may be poor when full color is reproduced.

In addition to the above components, a releasing agent or a softening agent may be added to the ink layer, if necessary, for the purpose of improving the releasability of the ink layer from the support and the thermal sensitivity. it can. When the release agent or the softener is used, the content is preferably 1 to 20% by weight based on the weight of the solid content in the ink.

The release agent and the softener include, for example,
Higher fatty acids such as palmitic acid and stearic acid; metal salts of fatty acids such as zinc stearate; fatty acid esters or partially saponified products thereof; fatty acid derivatives such as fatty acid amides; ester derivatives such as higher alcohols and polyhydric alcohols; Waxes such as wax, carnauba wax, montan wax, beeswax, wood wax, candelilla wax; having a viscosity average molecular weight of about 1,000 to 10,000
Polyolefins such as low molecular weight polyethylene, polypropylene and polybutylene; Low molecular weight copolymers of olefins and α-olefins with organic acids such as maleic anhydride, acrylic acid and methacrylic acid, vinyl acetate, etc .; Low molecular weight oxidation Polyolefins, halogenated polyolefins,
Methacrylic esters having long alkyl side chains such as lauryl methacrylate and stearyl methacrylate, homopolymers of methacrylic esters or copolymers with vinyl monomers such as styrene; polydimethylsiloxane, polydiphenylsiloxane And low-molecular-weight silicone resins and silicone-modified organic substances. These may be used alone or in combination of two or more.

The above components are dissolved or dispersed in a solvent to form a coating liquid solution (ink for image forming area), which is coated on a support by a known coating method and dried to form an image forming layer. Can be formed. Solvents that can be used when preparing an ink for an image forming area include, for example, alcohols such as ethyl alcohol and propyl alcohol; ketones such as acetone and methyl ethyl ketone; esters such as ethyl acetate; and aromatics such as toluene and xylene. Group hydrocarbons; ethers such as tetrahydrofuran and dioxane; amides such as DMF and N-methylpyrrolidone; and cellosolves such as methyl cellosolve. The solvents may be used alone or in combination of two or more.

When the above-mentioned solvent is added to the amorphous organic high-molecular polymer and the pigment is dispersed therein, a dispersion method is as follows.
The dispersion can be performed by a dispersion method known in the field of paints such as a ball mill and a dyno mill.

The thickness (dry layer thickness) of the ink layer is as follows:
0.1 to 1.0 μm is preferable, and 0.2 to 0.5 μm is more preferable. When the film thickness is less than 0.1 μm,
In some cases, a desired image density cannot be obtained.
If the thickness exceeds 0 μm, when an image is formed by the area gradation method, a shadow portion may be crushed or a highlight portion may be broken, so that good gradation reproducibility may not be obtained.

As for the optical density of the image forming area (ink layer) formed on the support, it is necessary that the reflection density of the image transferred and formed on the white support, which is the transfer object, is 1.0 or more. There is. When the reflection density is less than 1.0,
A clear image cannot be obtained.

-Support-The support that can be used for the thermal transfer material is not particularly limited, and a support material known as a support for melt transfer or sublimation transfer can be appropriately selected. Examples of the support material include synthesis of polyester films such as polyethylene terephthalate and polyethylene naphthalate, polyethylene-2,6-naphthalate, polycarbonate, polyethylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, and styrene-acrylonitrile copolymer. Resin materials are exemplified, and among these, polyester films such as polyethylene terephthalate and polyethylene naphthalate are preferred from the viewpoint of heat resistance.

The thickness of the support is preferably 10 μm or less, more preferably 7 μm or less. Further, the surface of the support on the side where the image forming area is not provided may be subjected to a surface treatment such as a release treatment, if necessary. As the release treatment, for example, JP-B-58-13
No. 359, JP-A-1-234292, JP-A-1-29
No. 5893, No. 3-15554, No. 4-79
No. 317, Tokuhei 5-71397, Tokuhei 5-713
No. 98 and the like.

Further, a back layer may be provided on the surface of the support on which the image forming area is not provided. The back layer contains a binder resin, a lubricant such as a phosphate-based surfactant, a filler, and the like. Examples of the binder resin include ethyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, methyl cellulose, cellulose acetate, cellulose acetate butyrate, cellulose derivatives such as nitrified cotton, polyvinyl alcohol, polyvinyl acetate, polyvinyl butyral, polyvinyl acetal, polyvinyl pyrrolidone, and polyacrylic acid. ester,
Examples thereof include vinyl resins such as acrylonitrile-styrene copolymer and polyacrylamide, and polyesters.
Among them, a resin obtained by crosslinking a resin having a hydroxyl group among the above resins with a polyisocyanate or the like is particularly preferable.

The ink layer provided on the support of the thermal transfer material of the present invention contains a pigment and an amorphous organic high molecular polymer as main components. The viscosity of the ink layer is higher than that of the melt-type transfer material, and the viscosity of the ink layer is 10,000 cps or more even at a transfer temperature of 150 ° C. without lowering to 1000 cps or less as in the case of the thermal transfer material. Therefore, a high-resolution image that is sharp and can express characters such as 4 points is obtained, and the entire ink layer is peeled off at the joint surface of the thermal transfer material with the support or the like. A high-quality image with high reproducibility and excellent gradation reproducibility can be obtained.

As described above, by using the thermal transfer material of the present invention, even when the thermal transfer material on which the image forming area is formed is wound into a roll, the loss of the image forming area is suppressed, and density unevenness or the like is suppressed. Thus, a high-quality image free from image defects can be formed stably.

<Production Method of Thermal Transfer Material> In the production method of the thermal transfer material of the present invention, a fixed amount of the heat transfer material is placed on the support in parallel with the transport direction of the long support, that is, along the long direction. A solid-state thermal transfer material is manufactured in which image forming areas of cyan, magenta, yellow, and black are sequentially printed at a predetermined interval. In the manufacture, for printing a region of 0.5 to 5 mm from the front end of the printing portion of the intaglio printing for printing, corresponding to the front end in the transport direction of the image forming area to which the ink has been transferred, toward the outside of the printing portion. A printing intaglio having an average cell volume on the surface of the intaglio that is 5 to 90% of the cell volume of the printing portion corresponding to the same area as the area is used. Here, the print portion is, for example,
As shown in FIG. 1, a portion corresponding to the area 7 of the printing intaglio 6 where the image forming area 3 can be printed on the support.

In the method for producing a thermal transfer material according to the present invention, the printing intaglio may be formed from the leading end of the printing portion of the printing intaglio, which corresponds to the leading end in the transport direction of the image forming area to which the ink has been transferred. 0.5 ~
An intaglio printing plate is used in which a cell is provided in a region of 5 mm (hereinafter, sometimes referred to as a "tip plate portion") so that the average cell volume is smaller than the cell volume of the printing portion. Specifically, the average cell volume is 0.5 to 0.5 to the outside of the printing portion from the front end of the printing portion of the intaglio printing for printing, which corresponds to the front end portion in the transport direction of the image forming area to which the ink has been transferred. A volume of 5 to 90% of the cell volume of the printing portion, which corresponds to the same area as the 5 mm region (tip plate portion).

The portion where the cells are arranged so as to be smaller than the cell volume of the printing portion (that is, the leading end portion) corresponds to the leading end of the intaglio printing portion corresponding to the leading end in the image forming area in the transport direction. In addition, from the end of the image forming area in the transport direction to the outside of the image forming area,
It is also preferable to provide the same in the region of m (hereinafter, sometimes referred to as “end plate portion”). The preferred average cell volume is the same as in the case of the tip plate. By providing the terminal plate portion, a thermal transfer material capable of stably forming a higher quality image can be manufactured.

In the intaglio printing plate used in the method for producing a thermal transfer material of the present invention, cells having a fixed volume are uniformly arranged in a portion (printing portion) where an image forming area can be printed, and ink is applied to this. When transferred onto the support, it is possible to print a solid image forming area having a certain pattern, and in the leading end portion and the terminating end portion,
Since the average cell volume is smaller than that of the printed portion, it is possible to print and form an ink layer having a small amount of ink as a whole, that is, a thin layer thickness. Incidentally, the ink layer with a small amount of ink in the leading end plate portion outside the printing portion is a portion which does not participate in image formation during thermal transfer as a thermal transfer material.

The average cell volume is an average cell volume of the entirety of the front plate portion or the terminal plate portion. If the average cell volume is within the above range, the cell volume in the region of the front plate portion or the terminal plate portion is obtained. May have any volume distribution, for example, may be configured in a distribution mode as shown in FIGS. That is, as shown in FIG. 1B, the average cell volume in the leading end plate portion 8 or the trailing end plate portion 9 corresponds to the leading end 3p of the image forming area 3 in the transport direction.
A mode in which the volume gradually decreases from the leading end portion 7p or the terminal end portion 7p 'of the printing portion 7 of the printing intaglio 6 toward the P or P' direction outside the printing portion 7 may be gradually reduced. As shown in FIG. 2B, the volume may be increased stepwise in the P or P ′ direction outside the printing portion 7. Further, as shown in FIG. 3B, a mode in which cells having a uniform volume are uniformly provided may be used, or another mode may be used.

Therefore, in the case of the above-described continuous decrease or the increase in the number of steps, the leading plate portion and the trailing plate portion have a predetermined cell volume required for image formation. It may have the same volume as the printing portion, that is, a volume (same volume) corresponding to 100% of the cell volume of the printing portion. Also, the leading end 7p or the trailing end 7 of the printing portion 7
In a mode in which the volume gradually increases from p ′ to the P or P ′ direction outside the printing portion 7 and the volume gradually increases, the gradual increase may be any of linear, concave, and convex shapes. May be accompanied.

The leading end and the trailing end of the printing portion of the intaglio for printing are, as shown in FIG.
Of the printed portion on the transport direction Q side, and the other end 7p 'facing the one end. The leading end plate portion 8 and the trailing end plate portion 9 correspond to the leading end ink region 4 and the trailing end ink region 5, that is, the intaglio portions to be printed.

As a method of reducing the cell volume of the intaglio printing plate to a predetermined volume, for example, a method of changing the depth of the cell itself while keeping the cell area on the surface of the intaglio constant, or a method of keeping the depth of the cell itself constant Then, a method of changing the cell diameter on the intaglio surface, a method of changing both of them, and the like can be mentioned, and any of these methods may be used.

As the intaglio plate for printing, a known intaglio plate generally used for gravure rotary printing, provided with the above-described leading plate portion, or the leading and trailing plate portions, is used. The known gravure intaglio can be appropriately selected from all forms, and examples thereof include a corrosion gravure plate, an electronic engraving gravure plate, and the like.According to these, an ink layer having a uniform thickness without screening is formed. Can be. Specifically, net gravure version, Darjan
Gravure, conventional gravure and the like can be mentioned.

By using the printing intaglio having the above-described leading and trailing end plates at the leading end or the leading and trailing end portions of the printing intaglio, the thermal transfer of the present invention as described above is achieved. Material can be obtained.

The amount of ink in the printed portion is as follows:
Normally, the minimum amount that does not generate cell lines of the plate is the minimum amount,
Specifically, it is preferable that the amount is obtained by adding a necessary amount for forming an image by transfer and a safety factor. In the leading end plate portion and the peripheral end plate portion, naturally, it can be determined in the same manner as described above within a range smaller than the ink amount of the printed portion. Specifically, the thickness (when not dried) of the ink layer (image forming area) transferred onto the support at the time of printing is 0.
It is preferably from 1 to 10.0 μm, more preferably from 0.5 to 3 μm. Printing is performed within the above range to form an ink layer having the above-mentioned dry layer thickness.

The production of the thermal transfer material is carried out by gravure rotary printing, which can be carried out by appropriately selecting a known mode. For example, as shown in FIG. 5, yellow (Y), magenta (M) Gravure plates 12Y, 12M, corresponding to the four colors cyan, cyan (C) and black (K).
12C and 12K are continuously arranged, arranged so as to be in contact with the support 2, and rotated at a constant speed in the direction of the arrow R in synchronization with the support 2 to form an image forming area 3 (3M, 3M) on the support 2. 3
C, etc.). The arrangement order of the gravure plates is not limited to the above. FIG. 5 is a schematic side view showing an example of the manufacturing process of the thermal transfer material of the present invention.

The support 2 is made of a rotating gravure plate (12).
Y, 12M, 12C, 12K), and a desired amount of ink is sequentially supplied to the surface of the printing portion 7, the leading plate portion 8, and the terminating plate portion 9 on each of the gravure plates 12Y to 12K. Then, inks of each color of cyan, magenta, yellow, and black are continuously transferred on the support 2 at predetermined intervals in a fixed pattern shape so as to be parallel to the transport direction Q, thereby forming an image of each color. The area 3 is formed by printing.

Each of the gravure plates 12Y to 12K used for printing has a concave cell having a fixed cell volume in the printing portion 7, so that each printing area on the support 2 to which the ink has been transferred, That is, an ink layer having a substantially constant and uniform film thickness is formed in a region (image forming region of each color) where an image can be formed during thermal transfer as a thermal transfer material. Further, a layer having a smaller amount of ink than the ink layer is formed in the leading end ink region and the trailing end ink region of the ink layer. After printing and drying, it is wound up as a roll and stored in that state.

<Thermal Transfer Image-Receiving Material> The thermal transfer image-receiving material may be of any type as long as it has a function of retaining an image from the thermal transfer material of the present invention by thermal transfer. Synthetic paper and US448
No. 2625, US47666053, US
And the image receiving sheet described in the specification of US Pat. No. 4,933,258.

Among the above-mentioned thermal transfer image-receiving materials, materials usable as a support for an image-receiving sheet having a thermal adhesive layer (image-receiving layer) containing at least an organic high molecular polymer include paper, polyester film, polycarbonate film and polypropylene film. And a plastic film such as a polyvinyl chloride film. The support can be used as it is as a transfer object. When used for proofing, in order to form an image on the same paper as the printing paper, a transfer image may be first formed on a plastic film, and the transferred image may be retransferred to the printing paper to form an image. .

<Thermal Transfer Recording Method> Next, a thermal transfer recording method for recording an image using the thermal transfer material of the present invention will be described. Examples of the thermal transfer recording method include a thermal transfer recording method using a heating device such as a thermal head or an energizing head.

In the thermal transfer recording method using a heating device such as a thermal head, a laminate in which a thermal transfer image-receiving material is laminated on the surface of an ink layer of a thermal transfer material is prepared, and an upper portion (image forming layer) of the thermal transfer material of the laminate is prepared. Heat is applied to the surface of the heat-generating element using a thermal head or the like while controlling the image in a heating manner, and then the thermal transfer image-receiving material is separated from the thermal transfer material. Thereby, the entire ink layer in the heated area, that is, the ink layer having a thickness provided in the area to which heat is applied is peeled off at the bonding surface of the thermal transfer material with the support or the like, and an image is formed on the thermal transfer image receiving material. Can be formed. This is advantageous in that the device can be simplified.

As a method for forming the laminate, for example, a vacuum contact method, a transfer side of a thermal transfer material (image forming layer side) and an image receiving side of a thermal transfer image receiving material (image receiving layer side) are overlapped and applied. A known method such as pressure, a method of passing through a heating roller, a method of mechanically attaching a thermal transfer image receiving material onto a metal drum while pulling the same, and a method of applying a thermal transfer material on the metal drum while also mechanically pulling the material to adhere the same. Can be mentioned.

[0062]

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples. still,
“Parts” in the examples all represent “parts by weight”.

Example 1 <Preparation of Intaglio for Printing> First, 200 lines /
Prepare a commercial intaglio having a 25.4 mm screen,
In order to gradually reduce the amount of ink, the intaglio is placed in an area of 5 mm from the leading end 7p in the transport direction Q side toward the P direction outside the printing portion 7 so as to have a cell structure similar to that shown in FIG. ,
The cell volume continuously decreases in the P direction from the tip 7p, and the average cell volume is 3 times the cell volume of the print portion 7.
The tip plate portion 8 corresponding to 0% was provided. The terminal plate 9 shown in FIG. 1- (b) was not provided. The cylindrical printing plate for each color of yellow (Y), magenta (M), cyan (C), and black (K) is divided into four plates (12Y to 12Y) so as to have the same configuration as the embodiment shown in FIG. 12K), and these were continuously arranged so that they could be rotated while being in contact with the surface of the support. In addition, the cylindrical printing plates 12Y to 12
In K, plate portions 11Y to 11K each including a front plate portion 8, a printing portion 7, and a terminal plate portion 9 are provided in regions each corresponding to 1/4 of a cylindrical substrate.

<Preparation of Thermal Transfer Material> —Support— A polyester film having a thickness of 4.5 μm (Lumirror, manufactured by Toray Industries, Inc.) was prepared as a support.

-Preparation of Ink for Image Forming Area- Next, the following compositions were mixed to prepare four colors of inks for image forming area (I) to (IV). [Ink composition]-Polyvinyl butyral ... 12 parts (Denka butyral # 2000-L, manufactured by Denki Kagaku Kogyo KK)-Pigment (see Table 1 below) ... 12 parts-Dispersing aid ... 0 .8 parts (Solsperse S-20000, manufactured by ICI Japan) n-propyl alcohol (solvent) 110 parts

[0066]

[Table 1]

As shown in FIG. 5 (however, the terminal plate portion 9 is not provided), the support 2 is provided with a four-plate cylindrical printing plate (12Y to 1Y).
2K) and rotated in the direction of arrow R while sequentially supplying the inks (I) to (IV) for the image forming area to the printing portion 7 and the tip plate portion 8 on the intaglio of each color, respectively. It was transported at a constant speed of 100 m / min. Support 2
Is conveyed in the direction of arrow Q, and cyan, magenta,
Ink of each color of yellow and black is transferred in a solid pattern continuously at a predetermined interval in a certain pattern shape,
The image forming area of each color was formed by printing. After printing, the sheet was conveyed to a predetermined drying area, dried, and then wound up in a roll form to obtain the thermal transfer material (1) of the present invention. As shown in FIG. 1- (a), the obtained thermal transfer material has an image forming area 3 of each color corresponding to the printing portion 7 of each intaglio, having a film thickness of 0.4.
An ink layer having a uniform thickness of μm was formed, and a tip ink region 4 in which the amount of ink gradually and continuously decreased was formed outside each image forming region 3 (P direction). In this embodiment, the terminal ink area and the back layer 10 shown in FIG. 1A are not formed.

<Evaluation> The roll-form thermal transfer material (1) obtained as described above was forcibly stored at 45 ° C. for 3 weeks, and the ink stain (transfer) on the surface of the support on the side where no image forming area was formed was obtained. The presence or absence of traces was visually evaluated according to the following criteria. The results of the evaluation are shown in Table 2 below. -Criteria-A: No transfer mark was observed. Δ: Slight staining was observed, but there was no problem in practical use. X: Staining due to transfer was remarkably observed.

(Example 2) Instead of the printing intaglio having the leading end portion used in the first embodiment, the printing intaglio having the leading end portion is used in the same manner as in the leading end portion 8 having the same structure as the leading end portion. A plate portion was further provided to produce a printing intaglio 6 having the same structure as that of FIG. 1- (b), and the roll-shaped thermal transfer material (2) was used in the same manner as in Example 1 except that the intaglio 6 was used. Was prepared. Using the obtained thermal transfer material (2), evaluation of ink stains (transfer marks) was performed in the same manner as in Example 1. The evaluation results are shown in Table 2 below.

Comparative Example 1 A roll-shaped thermal transfer material (3) was produced in the same manner as in Example 1 except that the intaglio printing plate used in Example 1 was not provided with a tip plate portion. Using the obtained thermal transfer material (3), evaluation of ink stains (transfer marks) was performed in the same manner as in Example 1. Table 2 below shows the evaluation results.
Shown in

[0071]

[Table 2]

From the results shown in Table 2, it is found that the cell volume continuously decreases from the leading end and the trailing end of the printing intaglio, corresponding to the leading end in the image forming area in the transport direction, to the outside of the printing portion. In the thermal transfer materials (1) and (2) of the present invention manufactured using the intaglio printing plate provided with the leading end portion and the terminating end portion, transfer due to pressure in the image forming area is suppressed even when wound up in a roll shape. As a result, loss in the image forming area could be prevented. In addition, the thermal transfer material (2) provided with both the leading end portion and the terminating end portion had a better degree of loss in the image forming area. On the other hand, in the thermal transfer material (3) produced using a printing intaglio having no tip printing portion having a small average cell volume from the printing portion tip of the printing intaglio to the outside of the printing portion, the image forming area Pressure transfer occurred due to local pressing by the edge portion at the peripheral end of the image forming apparatus, and a linear defect occurred in the image forming area.

[0073]

According to the present invention, even when the thermal transfer material on which the image forming area is formed is wound into a roll, the image forming area has no defects and high image quality without image defects such as uneven density. A thermal transfer material capable of forming a stable image stably can be provided.

[Brief description of the drawings]

FIG. 1A is a schematic cross-sectional view illustrating a state in which the amount of ink continuously and gradually decreases from a leading end and a trailing end of an image forming area toward the outside of the image forming area.
(b) is a diagram showing an intaglio surface where the cell volume is gradually reduced toward the outside of the printing portion.

FIG. 2A is a schematic cross-sectional view for explaining a state in which the amount of ink gradually decreases from a leading end and a trailing end in an image forming area toward the outside of the image forming area. (b) A diagram showing the intaglio surface where the cell volume decreases stepwise towards the outside of the printing part.

FIG. 3A is a diagram illustrating a state in which an ink layer having a uniform ink amount and being thinner than an image forming area is formed from a leading end and a trailing end of the image forming area in a conveying direction toward the outside of the image forming area. FIG. (b) A diagram showing a uniform intaglio surface with a cell volume smaller than that of the printed portion.

FIG. 4 is a diagram showing an example of the configuration of the thermal transfer material of the present invention.

FIG. 5 is a schematic side view illustrating an example of a manufacturing process of the thermal transfer material.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 thermal transfer material 2 support 3 image forming area 4 tip ink area 5 end ink area 6 intaglio for printing 7 intaglio printing portion 8 tip plate section 9 end plate section Q transport direction of support R rotation direction of cylindrical printing plate S Spacing between image forming areas

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Naoshi Miyaki 1-5-1, Taito, Taito-ku, Tokyo Toppan Printing Co., Ltd. F-term (reference) 2C068 AA06 BD23 BD33 2H111 AA01 AA14 AA17 AA26 AA27 BA03 BA11 BA14 BA33 BA38 BA53 DA06 2H113 AA03 AA06 BA03 BA17 BC06 CA31 CA34 DA03 DA35 DA48 DA50 DA53 DA54 DA57 DA58 DA63 FA10

Claims (9)

[Claims] 1. A thermal transfer material in which image forming areas of cyan, magenta, yellow, and black hues are successively solid printed on a support in parallel with a transport direction of the support, wherein ink is transferred. The average ink transfer amount in a region of 0.5 to 5 mm from the leading end in the conveyance direction of the image forming region toward the outside of the image forming region is 5 to 5 of the ink amount in the image forming region corresponding to the same area as the region. A thermal transfer material characterized by being 90%. 2. An image forming apparatus according to claim 1, wherein the transfer of the ink from the end of the image forming area in the conveying direction toward the outside of the image forming area is 0.5 to 0.5.
The average ink transfer amount in the 5 mm area is 5 to 9 of the ink amount in the image forming area corresponding to the same area as the area.
The thermal transfer material according to claim 1, which is 0%. 3. The printing is performed so that the ink amount in a region of 0.5 to 5 mm continuously decreases from the leading end and / or the trailing end of the image forming area toward the outside of the image forming area. The thermal transfer material according to claim 1. 4. An image forming apparatus according to claim 1, further comprising: moving from a leading end and / or a trailing end of the image forming area toward the outside of the image forming area by 0.5 to 0.5.
3. The thermal transfer material according to claim 1, wherein each area of 5 mm is printed with a fixed amount of ink. 5. The thermal transfer material according to claim 1, wherein the image forming area contains at least a pigment and an amorphous organic high molecular polymer. 6. A method for producing a thermal transfer material in which image forming areas of cyan, magenta, yellow, and black hues are successively solid printed on the support in parallel with the transport direction of the support, wherein the ink is transferred. The average cell volume on the surface of the printing intaglio in a region of 0.5 to 5 mm from the front end of the printing portion of the printing intaglio, corresponding to the front end in the transport direction of the image forming area, toward the outside of the printing portion. A method for producing a thermal transfer material, wherein printing is performed by a printing intaglio, which is 5 to 90% of the cell volume of the printed portion corresponding to the same area as the area. 7. A printing method for printing an area of 0.5 to 5 mm from the end of the printing portion of the intaglio printing for printing corresponding to the end of the image forming area to which the ink has been transferred in the transport direction, toward the outside of the printing portion. The average cell volume on the surface of the intaglio is 5 to 90 of the cell volume of the printed portion corresponding to the same area as the area.
The method for producing a thermal transfer material according to claim 6, wherein the printing is performed by using an intaglio for printing, which is%. 8. From the leading end and / or end of the printing portion of the intaglio printing for printing, 0.5 to 5 mm toward the outside of the printing portion.
8. The method for producing a thermal transfer material according to claim 6, wherein cells having a cell volume that is gradually reduced are arranged on the surface of the intaglio printing for printing in the region. 9. From the leading end and / or the trailing end of the printing portion of the intaglio printing for printing, 0.5-5 mm toward the outside of the printing portion.
8. The method for producing a thermal transfer material according to claim 6, wherein cells having a fixed cell volume are arranged on the surface of the intaglio printing for printing in the region.