JP2001010242A - Thermal transfer recording material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To realize excellent resolution and gradation in pixels and to keep a recording performance for a long time by making use of the advantages of a thermal transfer system and an ink jet recording system and by eliminating a defect, a problem of kogation in particular. SOLUTION: This thermal transfer recording material is a material which is led to a transfer part having a porous structure by a capillary phenomenon and is changed in a state by heating and transferred to an object of transfer opposed to the transfer part, and it contains dyestuff expressed by the formula. In the formula, A may have further a substituent and R1 denotes a hydrogen atom, an alkyl, an alkenyl, a phenyl, a cycloalkyl or the like, R2 and R3 denoting the alkyl, the alkenyl, the phenyl, the cycloalkyl or the like and X an oxygen atom or a sulfur atom, respectively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a thermal transfer recording method,
For example, a thermal transfer recording material used in a full-color image recording method in which a recording liquid containing a dye flies from a recording unit by selective heating according to image information and is transferred to an opposing photographic paper, particularly a recording liquid containing a cyan dye It is about.

[0002]

2. Description of the Related Art In recent years, as colorization of video cameras, computer graphics, and the like has progressed, the need for colorization of hard copies has rapidly increased. On the other hand, a color hard copy system such as a sublimation thermal transfer system, a melt thermal transfer system, an ink jet system, an electrophotographic system, and a heat-developed silver salt system has been proposed. Among these recording methods, methods for easily outputting high-quality images with a simple apparatus can be broadly classified into a dye diffusion thermal transfer method (sublimation thermal transfer method) and an ink jet method.

Among these recording methods, according to the dye diffusion thermal transfer method, an ink ribbon or sheet in which an ink layer in which a high concentration of transfer dye is dispersed in an appropriate binder resin is applied, and the transferred dye is A transfer medium such as photographic paper coated with a dyeing resin that receives the ink is brought into close contact with a certain pressure, and heat is applied according to the image information from a thermal recording head located on the ink sheet, and the ink sheet is The transfer dye is thermally transferred according to the amount of heat applied to the dye receiving layer.

The above operation is performed by subtracting the three primary colors of subtraction,
The so-called dye diffusion thermal transfer method is characterized by obtaining a full-color image having continuous gradation by repeating each of the image signals separated into yellow, magenta, and cyan. It is attracting attention as an excellent technology for obtaining high-quality images comparable to silver halide color photographs.

[0005] However, this method is a major drawback in that a large amount of waste is generated due to disposable ink sheets and high running costs are hampered.
This is the same in the fusion heat transfer system. As described above, the conventional thermal transfer method has high image quality, but the running cost is high because the dedicated photographic paper and the disposable ink ribbon or sheet are used.

Although the heat-developed silver halide method has high image quality, the running cost and the apparatus cost are also high because dedicated photographic paper and disposable ink ribbons or sheets are used. On the other hand, the ink jet method is described in JP-B-61-599.
No. 11 and Japanese Patent Publication No. 5-217, etc.,
According to image information, electrostatic suction method, continuous vibration generation method (piezo method), thermal method (bubble jet method)
In this method, a small droplet of the recording liquid is made to fly from a nozzle provided in a recording head and adhere to a recording member, thereby performing recording.

Therefore, there is almost no waste as in the case of using an ink sheet or the like, and the running cost is low. Recently, the thermal method has been widely used because it can easily output a color image. However, in the ink-jet method, the density gradation in the pixel is difficult in principle, such as that obtained by the dye diffusion thermal transfer method.
It is difficult to reproduce a high-quality image comparable to a silver halide photograph in a short time.

That is, in the conventional ink jet, since one droplet of ink forms one pixel, in-pixel gradation is difficult in principle, and a high quality image cannot be formed. Attempts have been made to express the pseudo-gradation by the dither method using the high resolution of the ink jet, but the image quality equivalent to that of the sublimation type thermal transfer system cannot be obtained, and the transfer speed has been remarkably reduced.

As described above, image quality, running cost,
There is no recording method that satisfies all requirements such as apparatus cost and transfer time. Recently, a new recording method that solves these problems has been proposed (see Japanese Patent Application Laid-Open No. 7-89107). That is, the recording liquid is guided to a transfer portion having a porous structure by capillary action, and heated by a suitable heating means such as a laser beam to vaporize the recording liquid or to reduce the diameter of the recording liquid to 1 μm.
This is a non-contact type dye flying type thermal transfer recording system in which a mist of m or less is generated and is transferred onto a photographic paper which is arranged to face through a gap of 10 to 300 μm.

In such a non-contact type thermal transfer recording system, the surface area of the heating section (transfer section) increases due to the above-mentioned porous structure, and the recording liquid is constantly supplied to the recording liquid heating section by capillary action, and is supplied there. In this state, a part of the recording liquid is evaporated by selectively applying a heat amount according to the recording information by a heating means (for example, a laser beam), and an electric power generated by a color video camera or the like is obtained. The amount of the recording material corresponding to the recording information corresponding to the typical image can be transferred to a non-recording medium by transferring it to a non-recording medium in the form of minute vapors or droplets.

Therefore, a large number of droplets having a small size can be formed in comparison with the known ink jet system, and the number of droplets generated can be freely controlled in accordance with the heating energy corresponding to the information recorded in the recording liquid heating section. Since it is possible to perform multi-value density gradation, it can be equivalent to a silver halide image or
It is possible to obtain a recording (for example, a full-color image) having a higher image quality.

Further, since it is a thermal transfer recording system, it has the above-mentioned features such as downsizing, easy maintenance, quickness, high quality of image, high gradation, and the like. However, it has been found that this thermal transfer recording system has the above-mentioned excellent features and also has a problem to be improved. That is, when the transfer is repeated by this method, charred (decomposed products of the dye and the like) accumulate in the transfer portion, and the so-called kogation, which causes the ejection holes to be clogged, occurs. As a result, the flying state of the recording material fluctuates, and the recording performance tends to deteriorate.

[0013]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a liquid crystal display having excellent resolution and pixel resolution while simultaneously utilizing the advantages of both the above-described thermal transfer system and the ink-jet system, and at the same time, eliminating those drawbacks, especially the problem of kogation. It is an object of the present invention to provide a thermal transfer recording material that can realize an inner gradation and maintain recording performance for a long time.

[0014]

Means for Solving the Problems The present inventors have found that kogation as described above occurs due to insufficient heat resistance of a dye used as a recording material, and by using a specific dye, The inventors have found that the heat resistance of the dye is sufficient, kogation can be greatly reduced, and the life of the head can be prolonged. That is, the present invention is directed to a thermal transfer in which a state is changed to a vaporized state or a droplet state by heating and is transferred to an object to be transferred which is opposed to the transfer part, which is guided by a capillary phenomenon to a transfer part having a porous structure. The present invention relates to a thermal transfer recording material containing a dye (cyan dye) represented by the following general formula (I).

Further, the present invention relates to a thermal transfer recording system for obtaining a full-color image by repeating thermal transfer of a dye corresponding to an image signal decomposed into three primary colors of a subtractive mixture of a yellow dye, a magenta dye and a cyan dye. A thermal transfer recording material containing a dye is guided to a transfer portion having a porous structure by a capillary phenomenon, and the state is changed by heating, and a thermal transfer recording method is used in which the material is transferred to an object to be transferred facing the transfer portion. The present invention relates to a full-color printing method characterized by using a dye represented by the following general formula (I) as a cyan dye. Here, “contained” means not only the case where the above-mentioned dye occupies a part but also the case where the above-mentioned dye occupies substantially 100% (the same applies to other parts of this specification).

[0016]

Embedded image

(Wherein, ring A represents a ring which may have a substituent, and R ¹ is a hydrogen atom, a substituted or unsubstituted alkyl group, an alkenyl group, a substituted or unsubstituted phenyl group or a cycloalkyl group. Wherein X is an oxygen atom or a sulfur atom, and R ² and R ³ represent a substituted or unsubstituted alkyl group, an alkenyl group, a substituted or unsubstituted phenyl group or a cycloalkyl group.

In the recording material of the present invention, R ¹ , R ² and R ^{3 each} have 1 to 1 carbon atoms in the alkyl or alkenyl moiety.
A linear or branched, substituted or unsubstituted alkyl or alkenyl group having 2 to 1 carbon atoms as a substituent;
8, an alkyl group or an alkoxy group, a halogen atom,
It is preferably a phenyl group having a fluorine-substituted alkyl group.

In this case, the substituted alkyl group is 2 to 25, preferably 2
-20, a 2-hydroxyethyl group, 2-
Hydroxypropyl group, 3-hydroxypropyl group, 4
A hydroxy-substituted alkyl group such as -hydroxybutyl group;
Phenyl-substituted alkyl groups such as benzyl group, p-chlorobenzyl group and 2-phenylethyl group; 2-methoxyethyl group, 2-ethoxyethyl group, 2- (n) propoxyethyl group, 2- (iso) propoxyethyl group , 2- (2-
Ethylhexyloxy) alkoxy-substituted alkyl such as ethyl group, 3-methoxypropyl group, 2-methoxypropyl group, 4-methoxybutyl group, 3-methoxybutyl group, 2,3-dimethoxypropyl group, 2,2-dimethoxyethyl group Group; 2- (2-methoxyethoxy) ethyl group,
2- (2-ethoxyethoxy) ethyl group, 2- (2-
(N) propoxyethoxy) ethyl group, 2- (2-
(N) butoxyethoxy) ethyl group, 2- {2- (2-
An alkoxyalkoxy-substituted alkyl group such as an ethylhexyloxy) ethoxydiethyl group; an aralkyloxy-substituted alkyl group such as a 2-phenethyloxyethyl group or a 2-benzyloxyethyl group; a 2-acetyloxyethyl group;
Acyloxy-substituted alkyl groups such as 2-propionyloxyethyl group and 2-trifluoroacetyloxyethyl group; alkoxycarbonyl-substituted alkyl groups such as 2-methoxycarbonylethyl group and 2-ethoxycarbonylethyl group; furfuryl group and tetrahydrofurfuryl group Heteroalkyl-substituted alkyl groups such as 2-allyloxyethyl group; aryloxy-substituted alkyl groups such as 2-phenoxyethyl group and 2- (p-chlorophenoxy) ethyl group.

As the unsubstituted alkyl group, a linear or branched alkyl group having 1 to 12 carbon atoms, specifically, ethyl, i-propyl, n-propyl, n-butyl, i-butyl -Butyl, pentyl, hexyl, 2-ethylhexyl, n-octyl, n-decyl, n-dodecyl and the like, among which those having 4 or more carbon atoms are preferable.
Examples of the alkenyl group include those having the same carbon number as the above-mentioned alkyl group and having at least one double bond. When R ¹ , R ² and R ³ are cycloalkyl groups, a cycloalkyl group having 5 to 10 carbon atoms which may have a substituent having about 6 or less carbon atoms, such as a cyclopentyl group or a cyclohexyl group, may be used. No.

When R ¹ , R ² and R ³ are a substituted phenyl group, examples of the substituent include a linear or branched alkyl group having 1 to 8 carbon atoms; a linear alkyl group having 1 to 8 carbon atoms. And a branched alkoxy group; a fluorine atom, a chlorine atom, a bromine atom,
A halogen atom such as an iodine atom; and an alkyl group having 1 to 8 carbon atoms substituted by a fluorine atom such as a trifluoromethyl group.

Particularly preferred as R ¹ are those having 4 carbon atoms.
Straight-chain or branched-chain alkyl or alkenyl group having 1 to 12 carbon atoms; 1 straight-chain or branched-chain alkoxy group having 1 to 4 carbon atoms, 1 carbon atom substituted with a phenyl group, phenoxy group, allyloxy group, etc. A linear or branched alkyl group having 4 to 4 carbon atoms; an alkyl group having 5 to 10 carbon atoms substituted with a tetrahydrofuryl group; a cyclohexyl group; a phenyl group; Examples include an alkyl group, a linear or branched alkoxy group having 1 to 4 carbon atoms, a phenyl group substituted with a fluorine atom, a chlorine atom, a trifluoromethyl group, and the like.

Particularly preferred as R ² and R ³ are:
A linear or branched alkyl or alkenyl group having 4 to 12 carbon atoms; substituted with a linear or branched alkoxy group having 1 to 4 carbon atoms, a phenyl group, a phenoxy group, an allyloxy group, or the like. A linear or branched alkyl group having 1 to 4 carbon atoms; a tetrahydrofurfuryl group;
A cyclohexyl group; a phenyl group; R ¹ ,
When R ² and R ³ are a substituted phenyl group, the substituent is 1
Arbitrary substituents may be combined in the range of ~ 3. R ¹ , R ² and R ^{3 each} represent an optionally substituted alkyl group or alkenyl group;
^It is preferable that the sum of the number of carbon atoms of ¹ , R ² and R ³ is 12 or more, more preferably 14 or more.

As described above, individual substituents have been described.
In particular, when X is an oxygen atom and R ¹ , R ² and R ³ are all unsubstituted alkyl groups having 4 to 12 carbon atoms, R ¹
Is an unsubstituted alkyl group having 4 to 12 carbon atoms, and R ² and R
Preferably, ³ is an unsubstituted alkyl group having 8 to 16 carbon atoms. Specifically, R ¹ is an n-butyl group, an i-butyl group, an n-hexyl group, an n-octyl group,
A 2-ethylhexyl group, R ² is an ethyl group, an n-propyl group, an i-propyl group, and R ³ is an n-octyl group, a 2-ethylhexyl group, a combination of n-hexyl groups,
Or R ² and R ³ are both n-butyl, i-butyl, n
A combination of -hexyl group, n-octyl group and 2-ethylhexyl group is preferred.

[0025]

[Table 1]

[0026]

[Table 2]

[0027]

[Table 3]

The compound represented by formula (I) used in the present invention can be easily produced according to a known reaction method. Specifically, the thermal transfer recording material of the present invention is vaporized by heating or generates a mist having a diameter of 20 μm or less, and is transferred onto an oppositely disposed transfer object via a gap of 10 to 1000 μm. Liquid recording material. By non-contact transfer through such a gap, as described above, high image quality and immediacy can be obtained, and the size and weight of the device can be reduced, and no waste is generated.
It can be transferred to plain paper, and color recording with low power consumption and low running cost can be performed.

Further, the above-mentioned porous structure has a function of supplying and holding the recording material to the transfer section by its capillary action, and in particular, has a side or diameter of 0.2 to 3 μm.
It preferably has a height of 15 μm. In this case, 0.
A porous structure is formed by arranging three or more rows and three or more rows of fine columnar bodies having a side or diameter of 2 to 3 μm and a height of 1 to 15 μm at intervals of 0.3 to 3 μm. Good.

Such a porous structure (for example, a concavo-convex structure composed of a large number of columns) has the following three remarkable effects. That is, the first effect is that the recording liquid can be spontaneously supplied to the recording portion by the capillary phenomenon due to the large surface area formed by the above-mentioned uneven structure.
The second effect is that the surface tension of the liquid generally decreases as the temperature increases, so that when the recording liquid is heated, the surface tension at the center of heating of the recording liquid is lower than the surface tension at the outer periphery thereof, and the recording liquid at the center part is reduced. However, since the heating portion has the above-described uneven structure, the movement of the recording liquid to the outer peripheral portion can be suppressed, and a decrease in transfer sensitivity can be prevented.

The third effect is that a large number of concave portions in the concave-convex structure of the recording portion each act as a fine ejection portion, so that the number of very fine recording liquids corresponding to the amount of heat applied to the recording portion is reduced. Droplets are ejected, fly into the space, and are adsorbed on the opposing recording medium such as photographic paper. Using this principle,
The in-pixel gradation that was impossible with the ordinary ink-jet method was enabled.

That is, by providing the above-mentioned porous structure (concavo-convex structure) in the heating section, the surface area is increased, and the recording liquid can be constantly supplied to the recording liquid heating section by capillary action and held there. In this state, a heating means (for example, a laser beam) is used to selectively apply an amount of heat according to the recorded information, thereby evaporating a part of the recording liquid to cause a pressure rise, and the electric power generated by a color video camera or the like. The recording material in an amount corresponding to the recording information corresponding to the typical image is converted into fine droplets, transferred to the recording medium, and transferred onto the recording medium.

In this case, a large number of droplets having a small size can be formed as compared with the known ink jet system, and the number of droplets generated can be freely adjusted according to the heating energy corresponding to the information recorded in the recording liquid heating section. Since control can be performed, multi-value density gradation can be achieved, and recording (for example, a full-color image) having image quality equal to or higher than that of a silver halide image can be obtained.

Therefore, using a head having a special structure capable of thermally transferring very fine recording droplets on demand, at least 128 or more density gradations within one pixel per color. An ink jet system capable of expressing can be realized. To form such a porous structure, for example, a method of laminating porous alumina having an average particle size of 0.1 to 2 μm to a thickness of 5 to 20 μm, an average particle size of 0.5 to
A method of laminating 3 μm glass beads to a thickness of 5 to 20 μm, a method of growing a large number of silicon whiskers having an average diameter of 0.5 to 2 μm and a height of 2 to 10 μm on a substrate at an interval of 1 to 3 μm, and the like. Can be manufactured.

However, in order to accurately control the transfer amount, in particular, a semiconductor processing technique such as RIE (reactive ion etching) or powder beam etching is used to make the size of one side or diameter 0.5 to 3 μm. Height 1-15μ
A structure in which fine columns made of glass or silicon having a size in the range of m are regularly arranged in three or more rows and three or more columns at intervals of 0.5 to 10 μm is preferable.

Further, a porous structure having a heat resistance of 300 ° C. or more is formed, and the generated droplet is supplied to
It is preferable to fly the recording medium facing the recording medium with a gap of 1000 μm. Such a porous structure,
Although it has the above-mentioned excellent action, it is small in size, so that during recording (especially repetitive recording), a deterioration product due to heating of the recording material, for example, a decomposition product adheres to the porous structure, and the clogging occurs. And tends to impair its effect.

However, the dye of the general formula (I) used in the recording material of the present invention has a sufficient heat resistance to heating and hardly causes kogation due to decomposition products. Even at times, the action of the porous structure can be maintained and effectively exerted. When the recording material of the present invention is heated to 300 ° C. or more, 90% by weight or more is vaporized and the residue is 10% by weight or less, and the dye (dye) is 5% at 50 ° C. or less. % Or more of a solvent having a boiling point of 150 ° C. or higher to be dissolved or dispersed.

The solvent used in this recording liquid should be one that sufficiently dissolves or disperses the above-mentioned dye, and has a boiling point of 150 ° C. or higher. This is because the above-mentioned porous structure has a large surface area, and if the boiling point is not higher than 150 ° C., the solvent evaporates or volatilizes to dry the recording portion, and the recording liquid concentration fluctuates, and the recording performance changes. Is to deteriorate.

Particularly, the solvent has a melting point of 50 ° C. or less, a boiling point in the range of 150 ° C. to 400 ° C., and is preferably colorless. When the melting point exceeds 50 ° C., the melting point of the dye is generally 100 ° C. or higher. Therefore, the recording liquid prepared by mixing the dye and the solvent solidifies within a range from room temperature, which is the non-transferred recording part temperature, to 50 ° C. Easier to do.
If the boiling point is lower than 150 ° C., the recording portion is exposed to the atmosphere, so that only the solvent tends to volatilize from the recording liquid. When the boiling point is 400 ° C. or higher, the efficiency of vaporization is low, and the transfer sensitivity tends to decrease.

The molecular weight of the solvent is preferably 450 or less. If the molecular weight is too high, the expansion rate during vaporization is low, and the transfer sensitivity tends to decrease. Further, a solvent having a residual ratio of 0.01% by weight or less when heated to 200 ° C. in air is preferable. The solvent is PPC paper (plain paper),
It is preferable to have the property of being spontaneously absorbed by fibers such as art paper from the viewpoint of transfer to plain paper.

The solvent is 5% by weight of the above dye at 50 ° C. or less.
As described above, especially in order to dissolve 10% by weight or more, the value of the solubility parameter of the solvent at 25 ° C. (as defined by JH Hildebrand) is preferably in the range of 7.5 to 10.5. preferable. Further, it is preferable that the flash point is 150 ° C. or higher, the toxicity to the human body is low, and the color is colorless. When the solubility parameter exceeds 10.5, the solubility of the dye becomes low, and the reproducibility of the transfer sensitivity is liable to deteriorate due to the adsorption of water vapor in the air. When the solubility parameter is less than 7.5, the solubility of the dye tends to be low.

Specifically, di- and trialkyl esters of aromatic carboxylic acids such as phthalic acid and trimellitic acid; succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, dodecandioic acid Dialkyl esters of aliphatic dicarboxylic acids such as; octanoic acid, nonanoic acid, decanoic acid, dodecanoic acid, alkyl esters of aliphatic monocarboxylic acids such as myristic acid; diethylene glycol, triethylene glycol,
Dialkyl ethers of glycols such as tetraethylene glycol; monoalkyls of glycols such as ethylene glycol, propylene glycol, 1,4-butanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, and 2,2,4-trimethyl-pentanediol Ether monoalkyl esters; ethylene glycol, propylene glycol,
1,4-butanediol, diethylene glycol, triethylene glycol, tetraethylene glycol, 2,
Examples include dialkyl esters of glycols such as 2,4-trimethyl-pentanediol; and aromatic hydrocarbons such as alkylbenzene and alkylnaphthalene.

The alkyl group of the alkyl ester of the carboxylic acids is substituted with a linear or branched unsubstituted alkyl group or a heterocyclic group such as an alkoxy group, an aryloxy group, an aryl group or a tetrafurfuryl group. An alkyl group having 1 to 20 carbon atoms is suitable. Further, as the alkyl group of the above-mentioned alkyl esters and alkyl ethers of glycols, a linear or branched one having about 1 to 20 carbon atoms is suitable.

Particularly preferred solvents are dibutyl phthalate, dioctyl phthalate, diethyl sebacate, dibutyl sebacate, dioctyl sebacate, di (2-ethylhexyl) sebacate, diethyl azelate,
Dibutyl azelate, dioctyl azelate, di (2-ethylhexyl ester) azelate, ethyl decanoate, propyl decanoate, butyl decanoate, amyl decanoate, hexyl decanoate, heptyl decanoate, Octyl decanoate, (2-ethylhexyl) decanoate, decyl decanoate, ethyl octanoate, propyl octanoate, butyl octanoate, amyl octanoate, hexyl octanoate, heptyl octanoate, heptyl octanoate, octane Acid octyl ester, octanoic acid (2-ethylhexyl) ester, octanoic acid decyl ester, octanoic acid (2-butoxyethyl) ester,
Octanoic acid (2-phenoxyethyl) ester, octanoic acid (2-phenylethyl) ester, octanoic acid tetrahydrofurfuryl ester, dodecanoic acid butyl ester, myristic acid butyl ester, diethylene glycol dibutyl ether, triethylene glycol dimethyl ether, triethylene glycol dibutyl ether,
Tetraethylene glycol dimethyl ether, diethylene glycol monobutyl ether acetate, 2,2
4-trimethyl-pentanediol diisobutyl ester, acetyl tributyl citrate and the like.

The dyes used in the conventional ink-jet system generally include many acidic dyes, which are hydrophilic and flow on the recording paper when they adhere to the recording paper.
It is poor in water resistance, hardly develops color, and easily generates kogation due to self-decomposition due to heat during recording. On the other hand, since the above-mentioned cyan dye does not cause such a phenomenon, the cyan dye adheres well to recording paper and develops color more than enough, and kogation hardly occurs.

In addition, if a dialkyl phthalate is used in combination with the cyan dye, the solvent has good permeability into the recording paper, and can sufficiently adhere the dye. It also acts as a color development aid for coloring the dye. Therefore, when this recording liquid is used, transfer to PPC paper is possible, and a high-quality image can be formed. Further, the dye concentration of the recording liquid was conventionally at most 5% by weight, but in the recording liquid composed of the above combination, the solvent amount can be set in a wide range of 50 to 90% by weight, and the dye concentration is 10% by weight. As described above, the image density can be improved.

It is known that a part of the compound represented by formula (I) used in the present invention is used as a dye for sublimation transfer recording (see, for example, JP-A-64-42286). However, when these compounds are used as thermal transfer recording dyes according to the present invention, a recording material which can realize extremely excellent resolution and high-quality images, particularly gradation in pixels, and can maintain recording performance for a long time Is very surprising and surprising to exhibit the properties as a recording dye which brings about.

The transfer head using the recording material of the present invention may comprise a recording section provided with heating means, an ink tank for storing recording liquid, and a recording liquid passage connecting the recording section and the ink tank. The entire transfer head can be heated to 50 ° C. in order to adjust the viscosity of the recording liquid. In order to shorten the transfer time, two recording units are provided on one recording head.
More than one can be provided. The recording liquid consumed in the recording unit can be continuously supplied to the recording unit through the recording liquid passage.

The heating means is a heating element such as a resistance heater,
A laser whose output changes in accordance with recording information, a combination of a laser and a laser light absorber (photothermal converter) provided in a recording section, or the like can be used. When a semiconductor laser is used as a laser, a small and lightweight head can be formed with high controllability. The resistance heater is manufactured by directly attaching a conductive substance such as polysilicon on the recording unit.

The photographic paper which can be used for transferring the recording material of the present invention is plain paper such as PPC paper, high-quality paper such as art paper, etc., in order to obtain a high quality image having particularly high gradation and density. In the, as a resin for coloring the dye, polyester,
Special paper made by applying polycarbonate, acetate, epoxy resin, polyvinyl chloride, etc. on a base paper can also be used. In order to improve the storage stability of the obtained image, it is effective to laminate a resin film on the photographic paper after transfer.

In order to achieve multicolor recording (particularly full-color recording) using the recording material of the present invention, a recording liquid containing a dye exhibiting one of the three primary colors of subtractive color mixing, and this dye are described below. A recording liquid containing at least one kind of dye exhibiting three subtractive primary colors is selectively heated. For example, this operation is decomposed into yellow (Y), magenta (M), and cyan (C). Full colorization can be achieved by repeating each of these image signals.

With the demand for high performance of the printing technology in recent years, in full-color printing, it is required to carefully select the color tone of each of Y, M, and C.
It is also excellent in that a beautiful color tone satisfying the demand can be obtained. The dye of the present invention is preferable because a beautiful cyan color tone can be obtained particularly when transferred to recording paper coated with a base paper with a polyester resin.

[0053]

The present invention will be described below in more detail with reference to examples. First, a description will be given with reference to the drawings. 1 to 4 are views showing a vaporized thermal transfer printer head used in the embodiment. FIG. 1 (a) is a sectional view thereof, FIG. 1 (b) is a perspective view, FIG. 2 is a plan view, and FIG. FIG. 4 is a plan view showing a state in which a cover 7 described later is removed, and FIG. 4 is a partially enlarged view of a part thereof. FIG. 5 is a schematic diagram of a serial type printer. Figure 1
As shown in FIG. 3, the printer head 1 includes an aluminum head base 2 also serving as a heat sink, a vaporizing section heated by a heater according to image information, and a recording liquid for guiding the recording liquid to the vaporizing section by a capillary action. A heater chip 3 integrally formed on a silicon substrate and a driver IC 5 covered with a potting resin 4 are mounted, and wiring is formed so as to supply current to each heater in accordance with image data to be transferred. Printed circuit board 6 and driver I
It is composed of a cover 7 which also serves as protection of C5 and a supply path of the dye.

Here, a recording liquid introduction hole 8 for introducing recording liquid into the printer head 1 is provided in the head base 2.
When the heater chip 3 is adhered to the head base 2, a groove 9 is formed as an escape area for an excess adhesive that protrudes.
The inside of the cover 7 is a recording liquid supply path 10 for supplying the recording liquid to the recording liquid introduction path of the heater chip 3. In addition, the printed circuit board 6 includes a connector terminal 11.
Is provided. The surface of the heater chip 3 is covered with a Ni sheet 3a for protection, and a sheet resist 3b for forming a recording liquid introduction path is formed in a line inside the Ni sheet 3a.

Further, the heater chip 3 has a plurality of heaters for heating and vaporizing the recording liquid, wiring for applying a signal voltage based on an image signal to each of the heaters, and energizing the recording liquid. The recording liquid introduction path for supplying the liquid is formed by a lithography process. That is, as shown in FIG. 4 (a partial enlarged view of the vaporizing portion 13 at the tip of the heater chip 3 and its vicinity), for example, the pitch Lp
= 84.7 μm, 256 heaters 14 are formed in total. At this time, since one heater 14 transfers one dot, a resolution of 300 DPI can be realized. Each of the heaters 14 is formed of polysilicon having a size of 20 μm × 20 μm. The heater 14 is connected to an individual electrode 15 made of aluminum and a common electrode 16 for applying and energizing a signal voltage based on an image signal. Have been. Here, the vaporizing sections 13 are separated from each other by the partition walls 17, and the recording liquid is stored in the concave portion (the recording liquid storing section 18) surrounded by the partition walls 17. The diameter of the heater 14 is 2 μm on and around the heater 14 via a protective film SiO ₂ (not shown).
m, a small columnar body 19 having a partition wall of 2 μm and a height of 6 μm is provided as one of the constituent elements of the vaporizing section 13 in a group of 13 × 13.

The height of the small column 19 is determined by the recording liquid container 1.
8, that is, the height from the bottom surface to the top surface thereof, that is, the height of the partition wall 17 surrounding the recording liquid storage portion 18 of each heater 14, Are provided with a minute gap from each other so as to have a porous structure. Accordingly, the porous structure causes a capillary action, and thus each of the small columns 19 can hold the recording liquid in the recording liquid storage portion 18. At the same time, heater 1
When the recording liquid is heated in step 4, the surface tension of the recording liquid decreases as the temperature rises, but the recording liquid can be prevented from escaping from the vicinity of the surface of the heater 14 by the capillary action. Therefore, at the time of image transfer, a necessary recording liquid is continuously supplied.

As shown in FIG. 1A, the printer head 1 comes into contact with the recording material (printing paper) 12 at only one end 2a of the base, and has a predetermined angle with respect to the recording material 12. So it is held. Thus, the distance between the vaporizing section 13 and the recording material 12 can be kept constant. For example, the center position of the heater 14 of the vaporizing section 13 (FIG. 1)
The dashed line in (a)) is located 1.85 mm from the head base end 2 a in contact with the recording material 12, and the heater is formed on a 0.4 mm thick silicon substrate. The angle between the head base 2 and the recording material 12 such that the distance between the recording material 12 and the recording material 12 is 50 μm (however, the thickness of the adhesive layer between the silicon substrate and the head base 2 is 10 μm). At 14 °.

As described above, by appropriately changing the distance from the head base end portion 2a to the center position of the heater and the angle between the recording material 12 and the head base 2, the heater 14 and the recording material 12 Can be set to an arbitrary size. In this embodiment, a serial type printer as shown in FIG. 5 having the above-described printer heads 1Y, 1M and 1C for each color of yellow (Y), magenta (M) and cyan (C) was used. . Each printer head is connected to a head drive circuit board (not shown) via a flexible harness.

This serial type printer has a vertical (X
A paper feed roller 20 for transporting paper in the direction
A head feed shaft 21 for scanning the printer head in a direction (Y direction) orthogonal to the X direction is provided. The head feed shaft 21 is freely rotated by a motor (not shown) based on image information, and the printer head 1 is moved. It can be scanned. The paper feed in the vertical direction and the head scan in the horizontal direction are configured to be performed alternately.

Since each of the printer heads 1Y, 1M and 1C is provided with 256 heaters 14, the serial type printer used in this embodiment is
It has the ability to print 256 lines in one scan. In addition, at the end of one scan, the platen 2 is moved by the paper feed roller 20 also serving as a head support.
The recording material (printing paper) 12 on the sheet 2 is fed by 256 lines,
Since it is possible to start printing by sequentially changing the timing for each color so that the heads 1Y, 1M, and 1C of each color start printing from a predetermined position on the printing paper 12, a color image can be printed by one scan. You can do it.

Note that, instead of the serial printer shown in FIG. 5, a color printer having a line type head can be used. Hereinafter, an example of recording used in the above-described serial type printer will be specifically described.

Example 1 1) Synthesis of Dye 11.1 g of 1,1,3-tricyano-2-amino-1-propene in 60 ml of ethanol, 4- (Nn-octyl-Nn-butylamino) benzaldehyde
3 g, piperidine 0.5 g and ethyl alcohol 60 ml
Was added and the mixture was heated under reflux for 8 hours. After cooling, the precipitated crystals are filtered and dried, and have the following structural formula

[0063]

Embedded image

12.1 g of the crystal represented by the formula was obtained. This was dissolved in 100 ml of N, N-dimethylformamide,
After adding 2.9 g of sodium cyanide at 10 ° C. or lower and stirring for 2 hours, 7.1 g of bromine was added dropwise at 10 ° C. or lower and stirred for 1 hour. The reaction solution was discharged into 535 g of ice water, and the precipitated crystals were filtered. The obtained crystals were added to 45 ml of ethanol, 1.5 g of triethylamine was added, and the mixture was stirred at 50 ° C. for 1 hour. The reaction solution was discharged into 357 g of ice water and neutralized with concentrated hydrochloric acid. The precipitated crystals are filtered and dried, and have the following structural formula

[0065]

Embedded image

12.7 g of the crystal represented by the formula was obtained. 2.0 g of these crystals was added to 25 ml of N, N, -dimethylformamide.
Sodium hydride (60% in oil) 0.3
g was added at 40 ° C., and 1.2 g of iodoethane was added dropwise, followed by reaction at 75 ° C. for 2 hours. After cooling, the mixture was discharged into ice water, and the precipitated crystals were filtered and dried.

[0067]

Embedded image

No. in Table 1 shown by No. 0.8 of one dye
g was obtained. Λmax in acetone of 634 nm
And the melting point was 106 ° C.

2) Transfer Record No. 1 in Table 1 4% by weight of 1 dye in dibutyl phthalic acid
To obtain a cyan recording liquid. When this was introduced into the ink tank from the recording liquid introduction hole of the printer head shown in FIG. 1, the recording liquid spontaneously was introduced into the vaporizing portion at the tip of the recording heater chip through the passage. Next, by applying the following pulse voltage to the heater of the printer head, the recording liquid was thermally transferred to photographic paper.

(Pulse voltage condition) With 80 mW and one pulse for one gradation, ON time 12 μs and OFF time 2 μs, 256 pulses are applied per dot. As a result of thermal transfer under the above conditions, a dot having an optical density of 0.8 was formed on A6 plain paper as measured with a Macbeth reflection densitometer. When this transfer was continued, scorching occurred on the columnar portion of the printer head, making it impossible to transfer cyan.
A large number of prints of 0 sheets could be performed.

Example 2 Nos. In Table 1 were used as dyes. The same test as in Example 1 was carried out except that the dye No. 2 was used and a cyan recording solution dissolved in dibutyl phthalic acid at a concentration of 10% by weight was used. It was formed on plain paper, and when this transfer was continued, 7000 prints could be made.

Comparative Example 1 Solvent Blue 6 represented by the following structural formula as a dye
A test was performed in exactly the same manner as in Example 1 except that No. 3 was used. As a result, dots having an optical density of 0.7 could be formed.
At the time of printing, the columnar portion of the printer head was scorched, so that cyan transfer could not be performed.

[0073]

Embedded image

[0074]

The recording material of the present invention has a sufficient heat resistance to heating since the dye compound represented by the general formula (I) is used as the dye, and the kogation by the decomposition product is not significant. Almost no occurrence. For this reason, the function of the porous structure can be maintained even during repeated recording, and can be effectively exerted. In this case, a large number of small-sized droplets can be formed by the porous structure, and the number of generated droplets can be freely controlled according to the heating energy corresponding to the information recorded in the recording liquid heating section. Value density gradation becomes possible,
It is possible to obtain a recording (for example, a full-color image) having image quality equal to or higher than that of the silver halide image. In addition, since the recording is performed by the thermal transfer method, it has the features described above, such as downsizing, easy maintenance, quickness, high-quality images, and high gradation.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view (FIG. 1A) and a lower perspective view (FIG. 1B) of a printer head used in an embodiment.

FIG. 2 is a plan view of a printer head used in the embodiment.

FIG. 3 is a plan view of a printer head used in the embodiment.

FIG. 4 is a partially enlarged view of a printer head used in the embodiment.

FIG. 5 is a schematic view of a serial type printer used in the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printer head 2 Head base 3 Heater chip 4 Potting resin 5 Driver IC 6 Printed circuit board 7 Cover 8 Recording liquid introduction hole 9 Groove 10 Recording liquid supply path 11 Connector terminal 12 Recording material (printing paper) 13 Vaporization part 14 Heater 15 Individual electrode 16 Common electrode 17 Partition wall 18 Recording liquid storage unit 19 Column

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Miori Ishida 1000 Kamoshita-cho, Aoba-ku, Yokohama-shi, Kanagawa Prefecture Inside the Yokohama Research Laboratory, Mitsubishi Chemical Co., Ltd. No. Within the Kurosaki Plant of Mitsubishi Chemical Corporation (72) Kenji Shinozaki, Inventor 6-35, Kita-Shinagawa, Shinagawa-ku, Tokyo Inside Sony Corporation (72) Tatsuhiko Matsumoto, 6-35, Kita-Shinagawa, Shinagawa-ku, Tokyo No. Within Sony Corporation (72) Inventor Eiki Hirano 6-35 Kita Shinagawa, Shinagawa-ku, Tokyo F-term within Sony Corporation (reference) 2H111 AA12 AA21 AA27 AA47 AA48 BA03 BA21 BA39 BA45 BA47 BA55 BA71 BA76 BA77 4H056 CA01 CC04 CC08 CD08 CE03 DD03 DD28 DD29 FA03 4J039 BC03 BC13 BC15 BC16 BC20 BC32 BC33 BC50 BE12 GA06

Claims (14)

[Claims] 1. A thermal transfer recording material which is guided by a capillary phenomenon to a transfer portion having a porous structure, changes its state by heating, and is transferred to an object to be transferred facing the transfer portion. A thermal transfer recording material containing the dye represented by I). Embedded image (Wherein, ring A may have a substituent, and R ¹ represents a hydrogen atom, a substituted or unsubstituted alkyl group, an alkenyl group,
X is an oxygen atom or a sulfur atom; R ² and R ³ are a substituted or unsubstituted alkyl group, an alkenyl group, a substituted or unsubstituted phenyl group or a cycloalkyl group; Represents an alkyl group. ) 2. In the formula (I), R ¹ is a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms, and 1 to 1 carbon atoms.
The thermal transfer recording material according to claim 1, which is a alkenyl group, a phenyl group, or a phenyl group having an alkyl or alkoxy group having 1 to 8 carbon atoms, a halogen atom, or a fluorine-substituted alkyl group as a substituent. 3. The thermal transfer recording material according to claim 1, wherein X in the general formula (I) is an oxygen atom. 4. R ¹ , R ² and R in the general formula (I)
^{3. The} thermal transfer recording material according to claim ¹ , wherein ³ is a substituted or unsubstituted alkyl group or alkenyl group, and R ¹ , R ² and R ^{3 have} a total carbon number of 14 or more. 5. In the formula (I), R ² and R ³ are a substituted or unsubstituted alkyl group having 1 to 12 carbon atoms, an alkenyl group having 1 to 12 carbon atoms, a cyclohexyl group, or an alkyl having 1 to 8 carbon atoms. 4. The thermal transfer recording material according to claim 1, which is a phenyl group which may be substituted with a group, an alkoxy group, a halogen atom or a fluorine-substituted alkyl group. 6. Evaporated by heating or having a diameter of 1 μm
The thermal transfer recording material according to any one of claims 1 to 5, wherein the thermal transfer recording material is a recording material that generates a mist of m or less and is transferred onto an object to be transferred that is opposed to the medium with a gap of 10 to 300 µm. 7. The porous structure has a side or a diameter of 0.2 to 3 μm and a height of 1 to 15 μm.
The thermal transfer recording material described in any one of the above. 8. One side or diameter of 0.5 to 3 μm, 1 to 1
8. The thermal transfer recording material according to claim 7, wherein the porous structure is formed by arranging fine columns having a height of 5 [mu] m in three or more rows and three or more columns at intervals of 0.5 to 3 [mu] m. 9. A compound having a molecular weight of 450 or less and a melting point of 50.
C. or lower, a boiling point of 150 ° C. or higher and 400 ° C. or lower, a colorless solvent having a residual content of 0.01% by weight or less when heated to 200 ° C. in the air. 9. The thermal transfer recording material according to claim 1, wherein the dye represented by I) is dissolved at 50 ° C. or lower at 5% by weight or more. 10. The thermal transfer recording material according to claim 9, wherein the solvent is at least one selected from aromatic carboxylic esters, aliphatic carboxylic esters, glycol ethers, glycol esters, and aromatic hydrocarbons. 11. The thermal transfer recording material according to claim 10, wherein the aromatic carboxylic acid ester is a dialkyl phthalate. 12. The aliphatic carboxylic acid ester may be a dialkyl succinate, a dialkyl glutarate, a dialkyl adipate, a dialkyl suberic acid, a dialkyl azelate, a dialkyl sebacate, a dialkyl dodecandioic acid, octane. Acid alkyl ester, nonanoic acid alkyl ester, decanoic acid alkyl ester, dodecanoic acid alkyl ester or myristic acid alkyl ester (provided that the alkyl group of the alkyl ester is substituted with an alkoxy group, an aryloxy group, an aryl group or a heterocyclic group) The thermal transfer recording material according to claim 10. 13. The glycol ester is ethylene glycol, propylene glycol, 1,4-butanediol, diethylene glycol, triethylene glycol,
The thermal transfer recording material according to claim 10, which is a monoalkyl ether monoalkyl ester or dialkyl ester of tetraethylene glycol or 2,2,4-trimethyl-1,3-pentanediol. 14. The thermal transfer recording material according to claim 10, wherein the glycol ether is diethylene glycol dialkyl ether, triethylene glycol dialkyl ether or tetraethylene glycol dialkyl ether.