JPH10865A - Sublimation thermal transfer body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sublimation thermal transfer body on which. hues are constant all over the density areas on a recording image and the hues are constant at all times regardless of the number of recordings in the multiple recording and the sublimation thermal transfer body with a dye layer of laminate structure containing sublimation dyes of two kinds of hues ore more. SOLUTION: In a sublimation thermal transfer body with a dye layer of laminate structure containing the sublimation dyes of two kinds of different hues or more on a substrate, the values in respective other hues to a hue representing the highest value (Dh) of sum of products of blend ratio of respective sublimation dyes which belong to the same hue in the dye layer or more and the solubility of toluene are 0.5 × Dh or more, or the values in other respective color hues to a hue representing the height value (Eh) of sum of products of the blend ratio of respective sublimation dyes which belong to the same hue, the solubility to toluene and the coefficient of extinction are 0.5 × Eh of more.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sublimation type thermal transfer member, and more particularly, to a sublimation type thermal transfer member having no hue shift in all regions from a low density portion to a high density portion. The present invention also relates to a sublimation-type thermal transfer member capable of performing printing many times without lowering the density of a printed image and causing no hue shift depending on the number of printings.

[0002]

2. Description of the Related Art In recent years, the demand for full-color printers has been increasing year by year, and the recording methods of these full-color printers include an electrophotographic method, an ink-jet method, a thermal transfer method, and the like. Thermal transfer recording is widely used. This thermal transfer recording method
An image receiving sheet is superimposed on the ink layer surface or the dye layer surface of a thermal transfer body in which an ink layer in which a coloring agent is dispersed in a hot melt material or a dye layer in which a sublimable dye is dispersed in a resin binder is provided on a substrate. A thermal energy controlled by an electric signal by a head, a laser beam, or the like is applied to the ink layer or the dye layer, and the ink layer or the sublimable dye at that portion is thermally melt-transferred or sublimated onto the image receiving sheet to form an image. This is a recording method. As described above, the thermal transfer recording method is roughly classified into a thermal fusion transfer type and a sublimation transfer type according to the type of the thermal transfer body used. In particular, in the latter case, the dye is in principle applied to the thermal energy from the thermal head or the like. This method has an advantage that a halftone can be easily obtained because it is transferred in a monomolecular state, and is suitable for a full-color pudding. However, sublimation dyes used in the sublimation type thermal transfer recording method include transferability under high temperature (several hundred degrees) and short time (several milliseconds) application conditions by a thermal head, high density of recorded images, color clarity, There are many requirements such as image characteristics such as high light fastness and high storage stability, and safety by Ames test and the like, and sublimable dyes satisfying all of them are limited. Therefore, as the sublimable dye for each color of the sublimation type thermal transfer member used for a full-color printer, it is preferable to use one kind of sublimable dye such as yellow, magenta, and cyan. As a typical sublimation type thermal transfer material for three primary colors or a sublimation type thermal transfer material for special colors, a mixture of several sublimable dyes having different hues is often used.
For example, red dye and violet dye for magenta color, blue dye and green dye for cyan color,
For the black color, a yellow dye, a magenta dye and a cyan dye are used, and for the flesh color, a mixed dye such as a red dye, a violet dye and a yellow dye is used.

In general, a sublimation type thermal transfer member is generally manufactured by gravure printing. However, when a sublimation type thermal transfer member is manufactured by one-layer coating, printing is performed using the sublimation type thermal transfer member. A dye layer formed by dissolving or dispersing a sublimable dye in a solution of a resin binder in an organic solvent (eg, toluene, methyl ethyl ketone, dioxane, etc.), because a pattern is formed on the image when performing the process and the uniformity of the image is impaired. Apply coating liquid 2
In general, a sublimation-type thermal transfer member is manufactured by layer coating (for example, JP-A-63-32089). However, for example, a dye coating liquid for magenta containing a red dye and a violet dye is applied in two layers to produce a sublimation type thermal transfer member, and a gradation pattern image ( When a pattern image in which the density is gradually changed from low density to high density is output, the hue shift (e.g., the violet color in the middle / low density area is higher than the high density area) Magenta color). This is a disadvantage in the sublimation transfer type thermal transfer recording method, which has better halftone color reproducibility than other processes. On the other hand, in order to form one full-color image by the sublimation type thermal transfer recording method, one sublimation type thermal transfer body having each color dye layer of yellow, magenta and cyan (and black) is used, and each color is formed on the same image receiving sheet. A one-time recording method for forming a full-color image by forming an image is used, but in this case, most of the dye used for image formation in the dye layer is transferred to the image receiving sheet, so that image formation is performed. Even if unused dye remains in the dye layer portion not used in the above, the sublimation type thermal transfer body cannot be reused for image formation and is discarded. Therefore, this recording method has a disadvantage that the running cost is high.

[0004] In order to improve this drawback, various recording methods for forming an image by repeatedly using the same sublimation-type thermal transfer member and various sublimation-type thermal transfer members used in the method have been proposed. As a multiple recording method, a constant velocity mode method and a speed difference mode method have been proposed. Further, as a sublimation type thermal transfer body for multiple recordings, in particular, as a sublimation type thermal transfer body capable of performing recording many times without lowering the recording density, a sublimation type thermal transfer body having a laminated structure of two or more layers, such as resin A dye supply layer in which a sublimable dye is dispersed in a binder is provided on a support, and a dye transfer contribution layer is provided on the dye supply layer. A sublimation type thermal transfer member having a dye layer having a structure is known.

However, when recording is performed using a sublimation type thermal transfer body having a dye layer having a laminated structure containing two or more kinds of sublimation dyes having different hues as the sublimation type thermal transfer body,
A hue shift occurs between the low-density portion and the high-density portion of the recorded image, and when a large number of recordings are performed, the hue of the image formed on the image receiving sheet differs depending on the number of recordings. However, there is a problem that a hue shift occurs in the recorded image or a hue shift occurs between the middle and low density portions and the high density portion of the recorded image.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve such a problem. An object of the present invention is to provide a sublimation-type thermal transfer body in which hue is not shifted between a low-density portion and a high-density portion and the hue is constant in the entire density region of a recorded image. It is another object of the present invention to provide a sublimation in which the density of a recorded image does not decrease even when used repeatedly many times, and the hue is always constant regardless of the number of recordings, and the hue is constant in the entire density range of the recorded image. To provide a mold heat transfer member.

[0007]

SUMMARY OF THE INVENTION The object of the present invention is to provide a sublimation type thermal transfer member having a dye layer having a laminated structure containing two or more sublimable dyes having different hues on a support. When the sum of the product of the blending ratio of each sublimable dye belonging to the hue and the solubility in toluene is D1, D2, D3... Dn for each hue, the hue showing the highest value (Dh) is obtained. On the other hand, this is achieved by a sublimation-type thermal transfer member characterized in that the value in each of the other hues is 0.5 × Dh or more. Further, the object of the present invention is to provide a sublimation type thermal transfer member having a dye layer having a laminated structure containing two or more kinds of sublimable dyes having different hues on a support. The value obtained by adding the product of the mixing ratio of the dye, the solubility in toluene, and the extinction coefficient is E1, E2, E3,... En for each hue.
When h is the highest value (Eh),
This is achieved by a sublimation type thermal transfer member characterized in that the value in each of the other hues is 0.5 × Eh or more. Further, the object of the present invention is to provide a sublimation-type thermal transfer member having a dye layer having a laminated structure containing two or more sublimable dyes having different hues on a support. Is achieved by a sublimation-type thermal transfer member characterized in that the type and the compounding ratio thereof are equivalent to the type and the compounding ratio of the sublimable dye in the lower dye layer.

The term "different hue" means that a human recognizes the hue as a different hue, and human color sensitivity cannot be defined uniformly because it is low on the low wavelength side (yellow side). When the wavelength differs by 20 nm or more, preferably 40 nm or more, it is generally recognized as a different hue. The same hue is a hue that human beings recognize as the same hue. Generally, the hue is yellow, orange,
The colors are roughly classified into red, purple, blue, green, and the like. Further, the method of dividing the hue differs depending on the color to be formed. In addition, yellow is lemon yellow type and Yamabuki color type,
Yamabuki is yellow and red, magenta is red and violet, and cyan is green and blue.

The sublimation type thermal transfer member having a dye layer having a laminated structure includes, for example, a sublimation type heat transfer member in which two or more dye layers containing a sublimable dye are laminated, a dye transfer contributing layer and / or Or a sublimation type thermal transfer member having a low dyeing resin layer laminated thereon, the dye supply layer contains a sublimable dye, and the transfer contributing layer or the low dyeing resin layer may or may not contain a sublimable dye. .

In the sublimation type thermal transfer member of the present invention, the sum of the product of the mixing ratio of each sublimable dye belonging to the same hue in the dye layer and the solubility in toluene is D1, D2, D3,. When Dn, the value of each of the other hues is equal to or more than 0.5 × Dh with respect to the hue having the highest value (Dh), for example, when the dye layer has the hue 1 of the sublimable dye 1a, the hue 2 contains the sublimable dyes 2a and 2b and the sublimable dyes 3a, 3b and 3c having a hue of 3, the solubility of each sublimable dye in toluene is 1a.
t, 2at, 2bt, 3at, 3bt, 3ct,
The amount of each sublimable dye in the dye layer is 1aH, 2a
H, 2bH, 3aH, 3bH, 3cH, D1 in hue 1 = 1at × 1aH / 1aH D2 in hue 2 = [2 at × 2aH / (2aH + 2
bH)] + [2bt × 2bH / (2aH + 2bH)] D3 in hue 3 = [3 at × 3aH / (3aH + 3)
bH + 3cH)] + [3bt × 3bH / (3aH + 3b)
H + 3cH)] + [3ct × 3cH / (3aH + 3bH)
+ 3cH)], and when D2 shows the highest value, it means that D1 and D3 are 0.5 × D2 or more.

Further, in the sublimation type thermal transfer member of the present invention,
The highest value when the sum of the product of the compounding ratio of each sublimable dye belonging to the same hue and the solubility in toluene and the extinction coefficient in the dye layer is E1, E2, E3... En for each hue. For the hue indicating (Eh), that the value in each of the other hues is 0.5 × Eh or more means that, for example, the dye layers are sublimable dyes 1a and 1b of hue 1 and sublimable dyes 2a of hue 2 and When 2b is contained, the solubility of each sublimable dye in toluene is 1 at, 1 bt, 2
at, 2 bt, extinction coefficient is 1 AK, 1 BK, 2 AK, 2 AK
bk, the amount of each sublimable dye in the dye layer is 1 aH,
In the case of 1bH, 2aH, and 2bH, E1 in hue 1 = ｛1at × 1ak × [1aH /
(1aH + 1bH)]｝ + ｛1bt × 1bk × [1bH
/ (1aH + 1bH)]} E2 at hue 2 = {2at × 2ak × [2aH /
(2aH + 2bH)]｝ + ｛2bt × 2bk × [2bH
/ (2aH + 2bH)]}, and when E2 indicates the highest value, E1 is 0.5 ×
It means that it is E2 or more.

The solubility of each sublimable dye in toluene can be determined by a general method. For example, in a simple manner, a supersaturated amount of a sublimable dye is added to a fixed amount of toluene at room temperature, and the supernatant after standing overnight is left and right. The solubility of the sublimable dye may be calculated from the absorbance of the liquid and the previously measured extinction coefficient of the sublimable dye.

In the sublimation type thermal transfer member of the present invention,
The highest value (Dh) when the sum of the product of the blending ratio of each sublimable dye belonging to the same hue in the dye layer and the solubility in toluene is D1, D2, D3... Dn for each hue. It is particularly preferable that the value in each of the other hues is 0.7 × Dh or more with respect to the hue indicating

Further, since the density of a recorded image is determined by the product of the transfer amount of the sublimable dye and the extinction coefficient / light coefficient of the sublimable dye, the mixing ratio of each sublimable dye in the dye layer and the solubility in toluene are determined. It is preferable to consider the product of the extinction coefficients. That is, in a sublimation type thermal transfer member having a dye layer having a laminated structure containing two or more kinds of sublimable dyes having different hues on a support, the mixing ratio of each sublimable dye belonging to the same hue in the dye layer and toluene The sum of the product of the solubility and the extinction coefficient is E1 for each hue,
When E2, E3... En, the highest value (E
h), the value in each of the other hues is preferably 0.5 × Eh or more, and 0.65 × Eh.
It is particularly preferred that it is h or more.

The support used for the sublimation type thermal transfer member of the present invention includes polyester resin, polysulfone resin, polystyrene resin, polysulfone resin, polycarbonate resin, cellophane, polyamide resin, polyimide resin, polyarylate resin, polyethylene naphthalate resin and the like. Known organic resin films can be used. The thickness is suitably 0.5 to 20 μm, particularly 3 to 10 μm
Is preferred. A known heat-resistant release layer may be provided on the back surface of these organic resin films as needed.

Further, as the sublimable dye in the sublimation type thermal transfer member of the present invention, a sublimable dye known in this field, which sublimates or vaporizes at 60 ° C. or more, can be used. Examples of sublimable dyes include those used in thermal transfer printing, such as disperse dyes and oil-soluble dyes. Specifically, for example, C.I. I. Day sparse yellow 1,3,8,9,
16, 41, 54, 60, 77, 116, and the like. I.
Disperse Red 1,4,6,11,15,17,5
5,59,60,73,83, C.I. I. Disperse Blue 3,14,19,26,56,60,64,7
Solvent Yellow 77,11 such as 2,99,108
6, Solvent Red 23, 25, 27 and the like, Solvent Blue 36, 83, 105 and the like, and these dyes may be used alone or in combination.

The dye layer in the sublimation type thermal transfer member of the present invention has an organic binder holding a sublimable dye dispersed in a particulate or molecular form. The organic binder includes a thermoplastic resin, For example, a vinyl chloride resin, a polyamide resin, a polycarbonate resin, a polystyrene resin, an acrylic resin, a phenol resin, a polyester resin, an epoxy resin, a fluororesin, a polyvinyl acetal resin, a cellulose resin and the like can be mentioned. One of these resins may be used, but a plurality of them may be mixed or a copolymer of these may be used. Among these, cellulose resins and polyvinyl acetal resins are preferable from the viewpoint of solubility in a solvent, viscosity of a resin solution, and adhesion to a support, and particularly, polyvinyl acetoacetal and polyvinyl butyral are preferable.

The sublimation type thermal transfer member of the present invention can be easily manufactured by the following method.

1) Two or more sublimable dyes having different hues have the highest value (D) as the sum of the product of the mixing ratio of each sublimable dye belonging to the same hue and the solubility in toluene.
h) is dispersed in a binder solution comprising an organic binder and a solvent, with the kind and the mixing ratio of the sublimable dye such that the value in each of the other hues is 0.5 × Dh or more with respect to the hue showing h). The dye layer coating solution (A), or two or more sublimable dyes having different hues, is obtained by summing the product of the mixing ratio of each sublimable dye belonging to the same hue, the solubility in toluene and the extinction coefficient. A binder comprising an organic binder and a solvent in a kind and a mixing ratio of a sublimable dye such that the value in each of the other hues is 0.5 × Eh or more with respect to the hue showing the highest value (Eh). A method of applying two or more layers of the dye layer coating solution (B) dispersed in the agent solution on a support, drying and applying an aging treatment if necessary,

2) A dye layer coating solution (A) or a dye layer coating solution (B) in which a sublimable dye is dispersed in a particle form is coated on a support and dried to form a dye supply layer. A dye layer coating liquid (A) or a dye layer coating liquid (B) in which a sublimable dye is molecularly dispersed is applied onto the supply layer and dried to form a dye transfer contributing layer or a low dyeing resin layer. Aging treatment if necessary,

3) A dye layer coating liquid (A) or a dye layer coating liquid (B) in which a sublimable dye is dispersed in a particle form is coated on a support and dried to form a dye supply layer. A dye transfer contributing layer coating solution or a low dyeing resin layer coating solution containing an organic binder and a solvent as main components is applied on the supply layer and dried to form a dye transfer contributing layer or a low dyeing resin layer. Aging treatment if necessary,

4) A dye layer coating liquid (A) or a dye layer coating liquid (B) in which a sublimable dye is dispersed in a particle form is coated on a support and dried to form a dye supply layer. A dye layer coating liquid (A) or a dye layer coating liquid (B) in which a sublimable dye is molecularly dispersed is applied on the supply layer and dried to form a dye transfer contributing layer. A low-dyeing resin layer coating solution containing an organic binder and a solvent as main components is applied thereon, dried, and a low-dyeing resin layer is formed, and aging treatment is performed as necessary. Can be.

As the solvent for the coating liquid, a conventionally known solvent capable of dissolving and dispersing a sublimable dye, an organic binder and the like can be used.
For example, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone as ketones, toluene and xylene as aromatics, dichloromethane and trichloroethane as halogens, dioxane, tetrahydrofuran and the like, formamide, dimethylformamide, etc. , Dimethyl sulfoxide or a mixture of the above solvents.

As these solvents, it is preferable to use one that dissolves or disperses the sublimable dye to a predetermined concentration or more and one that sufficiently dissolves the organic binder.
More specifically, toluene, methyl ethyl ketone, and the like are particularly preferable in terms of cost, safety, evaporation rate, resin solubility, dye solubility, and the like. The solvent for measuring the solubility of the sublimable dye is the most versatile solvent as the solvent for the dye layer coating liquid of the sublimation type thermal transfer member. It is preferable to use toluene which is an aromatic solvent because it is a soluble dye.

In order to prepare the dye layer coating solution (A) in the method of producing a sublimation type thermal transfer body of the present invention, first, transfer under heat application conditions is performed by using two or more sublimable dyes having different hues. Sublimation dyes for three primary colors and sublimation type heat transfer materials for special colors that satisfy image characteristics such as image quality, recorded image density, color clarity, high light fastness or high storage stability, and the compounding ratio thereof. In this case, the value of the sum of the product of the mixing ratio of each sublimable dye belonging to the same hue and the solubility in toluene is the highest (Dh), and the value of the other hue is 0. If less than 5 × Dh,
A sublimable dye having the same hue as the hue and a high solubility in toluene is added to all the hues of less than 0.5 × Dh,
What is necessary is just to adjust so that the sum (D) of the product of the compounding ratio of the sublimable dye and the solubility in toluene is 0.5 × Dh or more.

In particular, the solubility of the sublimable dye having the lowest solubility in toluene is 0.5 × Dh.
If less than, the solubility of the sublimable dye in toluene with the same hue as the sublimable dye is 0.5 × Dh or more,
Preferably, the addition of a sublimable dye of Dh or more can reduce the compounding ratio of the sublimable dye for adjusting the value of D, and is selected in consideration of transferability under heat application conditions and image characteristics. Without decreasing the compounding ratio of the sublimable dye having low solubility in toluene as the main dye, the value of D was 0.5 ×
It is more preferable because it can be Dh or more.

As another method for preparing the dye layer coating solution (A), first, two or more sublimable dyes having different hues are used, and the transferability under heat application conditions, the density of the recorded image, the color Sublimation dyes for three primary color sublimation type thermal transfer bodies and special color sublimation type thermal transfer bodies satisfying image characteristics such as sharpness, high light fastness and high storage stability, and their compounding ratios are selected. When the value obtained by adding the product of the compounding ratio of each sublimable dye and the solubility in toluene to the hue showing the highest value (Dh) is less than 0.5 × Dh in another hue. By adding a sublimable dye having the same hue as the hue and having a low solubility in toluene to the hue exhibiting the highest value (Dh) to decrease the value of Dh, the value of D in other hues becomes 0.5 × Dh or more. It may be adjusted so that

Further, when a sublimable dye having the same hue as the hue and a low solubility in toluene is added to the hue having the highest value (Dh), the value of D in the hue does not become the highest value, and other hue values are not obtained. The value with the highest hue value (D
h) may be used as long as the value of D in the hue to which the sublimable dye having a low solubility in toluene is added is 0.5 × Dh or more.

These methods are preferably used when a sublimable dye having a very high solubility in toluene is present in one hue, particularly when a sublimable dye having a solubility in toluene of 2 × Dh or more is present. That is, when there is a sublimable dye having a very high solubility in toluene in one hue, 0.5 as described above is used.
A value obtained by adding a sublimable dye having the same hue as the hue and having high solubility in toluene to all the hues less than × Dh, and adding the product of the blending ratio of the sublimable dye in each hue and the solubility in toluene (D). Is adjusted to be 0.5 × Dh or more by adding a sublimable dye having the same hue as the hue and having low solubility in toluene to the hue having the highest value (Dh), thereby lowering the value of Dh. It is preferable to adjust the value of D in other hues to be 0.5 × Dh or more.

Further, the solubility of the sublimable dye to be added to toluene is such that the mixing ratio of the sublimable dye to be added is as small as possible, and the main dye selected in consideration of the transferability under heat application conditions and image characteristics. In order not to lower the compounding ratio of the sublimable dye having a high solubility in toluene, which is a value of 0.5 × Dh or less.

To prepare the dye layer coating solution (B) in the method for producing a sublimation type thermal transfer body of the present invention, first, transfer under heat application conditions is performed by using two or more sublimable dyes having different hues. Sublimation dyes for three primary colors and sublimation type heat transfer materials for special colors that satisfy image characteristics such as image quality, recorded image density, color clarity, high light fastness or high storage stability, and the compounding ratio thereof. At that time, the hue having the highest value (Eh) obtained by summing the product of the mixing ratio of each sublimable dye belonging to the same hue, the solubility in toluene, and the extinction coefficient is compared with the hue in each of the other hues. If the value is less than 0.5 × Eh, a sublimable dye having the same hue as the hue and having a large product of the solubility in toluene and the extinction coefficient is added to all the hues less than 0.5 × Eh, Mixing ratio, solubility in toluene and absorption The sum of the products of the light coefficients is 0.5 × E
h may be adjusted.

In particular, when the product of the solubility and extinction coefficient of the sublimable dye having the smallest solubility in toluene and the extinction coefficient in toluene is less than 0.5 × Eh, sublimation of the same hue as the sublimable dye is performed. By adding a sublimable dye having a product of solubility in toluene and an extinction coefficient of 0.5 × Eh or more, preferably Eh or more, the compounding ratio of the sublimable dye for adjusting the value of E can be reduced. In addition, the value of E was set to 0.
More preferable is 5 × Eh or more.

As another method for preparing the dye layer coating liquid (B), first, two or more sublimable dyes having different hues are used, and the transferability under heat application conditions, the density of the recorded image, the color Sublimation dyes for three primary color sublimation type thermal transfer bodies and special color sublimation type thermal transfer bodies satisfying image characteristics such as sharpness, high light fastness and high storage stability, and their compounding ratios are selected. The highest value (E) is obtained by summing the product of the mixing ratio of each of the sublimable dyes belonging thereto, the solubility in toluene, and the extinction coefficient.
h), the value in each of the other hues is 0.
When the value is less than 5 × Eh, a sublimation dye having the same hue as the hue and having a small product of the solubility in toluene and the extinction coefficient is added to the hue having the highest value (Eh) to lower the value of Eh. The value of E in the hue is 0.5 × Eh
The adjustment may be performed as described above.

When a sublimable dye having the same hue as the hue and having a small product of the solubility in toluene and the extinction coefficient is added to the hue having the highest value (Eh), the value of E in the hue is the highest. However, even when the value in other hues shows the highest value (Eh), the value of E in the hue to which a sublimable dye having a small product of the solubility in toluene and the extinction coefficient is added is 0.5 ×. If it is adjusted so as to be equal to or higher than Eh, that may be the case.

These methods are particularly useful when a sublimation dye having a very large product of the solubility in toluene and the extinction coefficient is present in one hue, especially when the product of the solubility in toluene and the extinction coefficient is 2 × Eh or more. It is preferable to use when present. That is, when there is a sublimable dye having a very large product of the solubility in toluene and the extinction coefficient in one hue, as described above, all the hues of less than 0.5 × Eh have the same hue as the hue. Add a sublimable dye with a large product of solubility and extinction coefficient for
The sum (D) of the product of the blending ratio of the sublimable dye in each hue, the solubility in toluene, and the extinction coefficient is defined as 0.
Rather than adjusting so as to be 5 × Eh or more, the value of Eh is reduced by adding a sublimable dye having the same hue as the hue having the highest value (Eh) and a small product of the solubility in toluene and the extinction coefficient to the hue. Accordingly, it is preferable to adjust the value of E in other hues to be 0.5 × Eh or more.

Furthermore, the product of the solubility of the sublimable dye to be added in toluene and the extinction coefficient should be as small as possible, as long as the mixing ratio of the sublimable dye to be added is as small as possible, and the transferability under heat application conditions and image characteristics are taken into consideration. In order not to decrease the compounding ratio of the sublimable dye having a large product of the solubility and the extinction coefficient with respect to toluene, which is the main dye selected above, 0.5 × Eh or less is particularly preferable.

As described above, the amount of the sublimable dye added to adjust the sum of the product of the blending ratio of the sublimable dye and the solubility in toluene, or the blending ratio of the sublimable dye and the solubility in toluene The amount of the sublimable dye added to adjust the sum of the product of the extinction coefficient and the extinction coefficient depends on the transferability under heat applied conditions, the density of the recorded image, the sharpness of the color, the high light resistance or the high storage stability. Since it is a dye that supplements the main sublimable dye that satisfies the image characteristics such as the above, the amount is preferably small.

Further, in a sublimation type thermal transfer member having a dye layer having a laminated structure containing two or more kinds of sublimable dyes having different hues on a support, the type of the sublimable dye in the upper layer of the laminated dye layer and its Another method for producing a sublimation type thermal transfer body having a compounding ratio equal to the type of the sublimable dye in the lower dye layer and the compounding ratio is as follows. First, two or more sublimable dyes having different hues, an organic binder And a coating solution for a lower layer containing a solvent as a main component is coated on a support and dried to form a lower layer (for example, a dye supply layer). Then, an upper layer (for example, a dye transfer contributing layer) is formed on the lower layer by the following method. and/
Alternatively, a low dyeing resin layer) may be formed.

That is, 1) a solvent and an organic binder having the same solubility of each of the sublimable dyes contained in the lower layer, and the sublimable dye of the lower layer optionally added (the compounding ratio is the same as in the lower layer) The upper layer is formed by applying an upper layer coating liquid containing as a main component onto the lower layer and drying to form an upper layer. A sublimation type thermal transfer member equivalent to the above can be obtained. This means that when the upper layer coating liquid is applied on the lower layer, two or more sublimable dyes having different hues in the lower layer are eluted into the upper layer at the same ratio as the dye ratio in the lower layer,
This is because the blending ratio of the sublimable dye in the upper layer becomes equal to the blending ratio of the dye in the lower layer.

2) A solvent in which the solubility of each of the sublimable dyes contained in the lower layer is 20 g / l or less, an organic binder, and a sublimable dye of the lower layer which is added as necessary (the compounding ratio is the same as in the lower layer). The upper layer is formed by applying an upper layer coating liquid containing as a main component onto the lower layer and drying to form an upper layer. A sublimation type thermal transfer member equivalent to the above can be obtained. This is because the solvent of the upper layer coating solution is a poor solvent for each sublimable dye contained in the lower layer,
This is because, when the upper layer coating liquid is applied on the lower layer, the amount of the sublimable dye in the lower layer that elutes into the upper layer can be made small enough not to cause a hue difference in the recorded image.

As the poor solvent in this case, a general solvent can be used. In particular, since the sublimable dye is a disperse dye or an oil-soluble dye, an alcohol solvent or a glycol ether solvent having a hydroxyl group is used. Is suitable.
Examples of alcohol solvents include methyl alcohol, ethyl alcohol, allyl alcohol, propyl alcohol, butyl alcohol, amyl alcohol, 3-methoxybutyl alcohol, hexyl alcohol, 2-methylpentanol, secondary hexyl alcohol, and 2-ethylbutyl. Alcohol, heptyl alcohol, secondary heptyl alcohol, octyl alcohol, 2-ethylhexyl alcohol, secondary octyl alcohol, nonyl alcohol, 2,6-dimethyl-4-heptanol, trimethylnonyl alcohol, and the like are exemplified. They can be used alone or as a mixture of several types.

Examples of glycol ether solvents having a hydroxyl group include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monoisoamyl ether, ethylene glycol monohexyl ether, and the like. Examples thereof include ethylene glycol mono-2-ethyl butyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, propylene glycol monomethyl ether, and propylene glycol monoethyl ether. These solvents can be used alone or as a mixture of several kinds. It is also possible to use a mixture of an alcohol solvent and a glycol ether solvent having a hydroxyl group.

3) An upper layer coating solution containing the sublimable dyes contained in the lower layer is added to the upper layer coating solution mainly containing an organic binder, a solvent, and a lower layer sublimable dye added as necessary. The sublimable dye is added in accordance with the difference in solubility in the working solution solvent, and the upper layer coating solution is applied on the lower layer and dried to form the upper layer. A sublimation-type thermal transfer material having the same sublimation dye mixing ratio as that of the sublimable dye in the lower layer can be obtained. This is when the upper layer coating liquid is applied on the lower layer,
When the dye ratio eluted from the lower layer to the upper layer is different from the dye compounding ratio in the lower layer, by adding a sublimable dye having a smaller elution ratio to the coating solution of the upper layer in advance according to the difference in solubility, With the total amount of the sublimable dye eluted from the lower layer to the upper layer and the sublimable dye previously added to the coating solution of the upper layer, the dye compounding ratio of the upper layer can be made equal to the compounding ratio of the sublimable dye in the lower layer. Because. Therefore, according to this method, a dye layer having a desired dye compounding ratio can be formed without restriction on the sublimable dye and the solvent.

4) An upper layer coating solution containing each of the sublimable dyes contained in the lower layer is added to the upper layer coating solution mainly containing an organic binder, a solvent, and an optional lower layer sublimable dye. Depending on the difference in solubility in the working solution solvent, a sublimable dye having a higher solubility in the upper layer coating solution solvent than the dye is added in the same hue as the sublimable dye, and the upper layer coating solution is applied to the lower layer. And dried to form an upper layer, whereby a sublimation-type thermal transfer body can be obtained in which the mixing ratio of two or more sublimable dyes having different hues in the upper layer is equal to the mixing ratio of the sublimable dye in the lower layer. . This is because, when the upper layer coating liquid is applied on the lower layer, when the dye ratio eluted from the lower layer to the upper layer is different from the dye compounding ratio in the lower layer, the ratio of the sublimable dye eluted from the lower layer to the upper layer is small. Depending on the difference in solubility, by adding a sublimable dye having a higher solubility in the solvent of the upper layer coating solution than the sublimable dye in the same hue as the sublimable dye to the upper layer coating solution in advance,
With the total amount of the sublimable dye eluted from the lower layer to the upper layer and the sublimable dye previously added to the coating solution of the upper layer, the dye compounding ratio of the upper layer can be made equal to the compounding ratio of the sublimable dye in the lower layer. Because. Therefore, according to this method, a dye layer having a desired dye compounding ratio can be formed without restriction on the sublimable dye and the solvent.

By doing so, the type and the mixing ratio of the sublimable dye in the upper dye layer become equal to the type and the mixing ratio of the sublimable dye in the lower dye layer. It is possible to prevent a hue shift between the image forming units and a plurality of recordings.

In the sublimation type thermal transfer member of the present invention, the lower layer in the dye layer having a laminated structure preferably has a higher dye concentration and / or a higher dye diffusion coefficient than the upper layer.

For example, a dye layer (lower layer) close to a support in a one-time recording sublimation-type thermal transfer member in which two or more dye layers containing a sublimable dye are stacked on a support is stacked thereon. It is preferable to have a higher dye concentration and / or a higher dye diffusion coefficient than the (upper layer). Further, a sublimation type thermal transfer body for multiple recordings in which a dye transfer contributing layer containing a sublimable dye (upper layer) or a low dyeing resin layer (upper layer) is laminated on a dye supply layer containing a sublimable dye (lower layer). Sublimation-type thermal transfer body for multiple recordings in which a dye transfer contributing layer containing no sublimable dye or a low dyeing resin layer is first laminated on a dye supply layer containing a sublimable dye, a dye containing a sublimable dye A dye supply layer such as a sublimation type thermal transfer body for multiple recordings in which a dye transfer contributing layer containing a sublimable dye and a low dyeing resin layer containing no sublimable dye are laminated on the supply layer, the dye transfer contributing layer or It is preferable to have a high dye concentration and / or a large dye diffusion coefficient as compared with the low dyeing resin layer.

Accordingly, the one-time recording method enables high-sensitivity recording, and a recorded image having a constant hue over the entire density range and excellent storage stability can be obtained. Also, in the multiple recording method, even if the sublimation type thermal transfer body is repeatedly used many times, it is possible to perform multiple recordings without reducing the image density, and the hue is always constant regardless of the number of recordings. A recorded image having a constant hue over the entire density range can be obtained.

The dye concentration in the upper dye layer is usually 80
% By weight or less, preferably 60% by weight or less,
It may not contain any dye. In the case where the dye is contained, it is desirable that the dye is dispersed in a monomolecular state that actually contributes to transfer from the viewpoint of preventing transfer density unevenness and sensitivity. In order to disperse the sublimable dye in a monomolecular state, as a solvent of the dye layer forming coating liquid,
A solvent having a high solubility of the sublimable dye may be used. The thickness of the upper dye layer is suitably 0.05 to 5 μm,
0.1 to 2 μm is preferred.

On the other hand, the dye concentration and the thickness of the dye layer in the lower dye layer are different between the sublimation type thermal transfer member for one-time recording and the sublimation type thermal transfer member for multiple recordings. In general, the dye concentration is suitably at most 80% by weight, preferably at most 70% by weight. Further, when the dye concentration when the upper layer contains a sublimable dye is 1,
The dye concentration of the lower layer is suitably larger than 1 and 5 times or less of the upper layer, particularly preferably larger than 1 and 3 times or less. Further, as the state of the dye in the lower dye layer, it is desirable that the dye is dispersed in a monomolecular state that actually contributes to transfer from the viewpoint of preventing transfer density unevenness and sensitivity. The thickness of the lower dye layer is suitably from 0.05 to 5 μm, and preferably from 0.1 to 2 μm.

In a sublimation type thermal transfer member for multiple recordings, the dye concentration in the lower dye layer such as the dye supply layer is usually 90%.
% Or less is appropriate, and preferably 86% or less,
In particular, about 5% to 60% is preferable. Further, when the dye concentration in the case where the dye is contained in the upper layer is 1, the dye concentration of the lower layer is suitably larger than 1.1 of the upper layer and 10 times or less,
It is preferably larger than 1.1 and 5 times or less, particularly preferably larger than 1.5 and 3 times or less.

The state of the dye in the lower dye layer is that the sublimable dye is dispersed in the form of particles, or that the sublimable dye is dispersed in the form of monomolecules and particles that actually contribute to transfer. This makes it possible to alleviate the dissolution of the dye and the difference in solubility when the upper dye layer is laminated, thereby preventing hue shift in multiple recordings. Further, by dispersing the sublimable dye in the lower dye layer in the form of particles or monomolecules and particles, it is possible to provide a concentration gradient in the lower dye layer and the sublimable dye in the upper dye layer. The particulate sublimable dye in the dye layer replenishes the lower and upper dye layers with the monomolecular sublimable dye and can maintain the concentration of the monomolecular sublimable dye constant, thereby reducing the density of the recorded image. A large number of recordings can be performed by repeatedly using the sublimation type thermal transfer member without lowering. The thickness of the lower dye layer is suitably from 0.1 to 20 μm, and from 0.5 to 10 μm.
Is preferred. In addition, in order to increase the diffusion coefficient in the lower dye layer, generally, a resin having a low softening point, a low glass transition temperature,
What is necessary is just to contain 90 weight%.

The particulate sublimable dye is, for example, insoluble in the organic binder when a dye layer coating solution comprising a sublimable dye, an organic binder and a solvent is applied and dried, and is in the form of particles. It means a sublimable dye that precipitates, and the presence of a particulate sublimable dye differs depending on the solvent even with the same organic binder and dye. The presence of the particulate sublimable dye can be easily observed with an electron microscope after forming the dye layer. Although the particle size of the particulate sublimable dye varies depending on the thickness of the dye layer, it is preferably 0.01 μm to 20 μm, particularly preferably 1 μm to
5 μm is preferred. By making the sublimable dye in the dye layer into a particle as described above, problems such as crystallization of the sublimable dye during long-term storage do not occur. In order to form a dye layer such as a dye supply layer containing a particulate sublimable dye, it is preferable to use a solvent having a solubility as low as possible for the sublimable dye as a solvent for the dye layer coating liquid. As such a solvent, any solvent may be used as long as it does not dissolve the sublimable dye very much. Among them, an alcohol solvent or a glycol ether solvent having a hydroxyl group is particularly suitable.

It is preferable to provide a dye transfer contributing layer as described in JP-A-5-64980 on a dye supply layer in a sublimation type thermal transfer member for multiple recording. The dye supply layer and the dye transfer contributing layer are each formed as a single layer on the support with the same amount of adhesion in each of the formulations, and each single layer is separately superimposed on the image receiving sheet, and the same as each single layer. When the heat energy is applied, the amount of the dye transferred to the image receiving sheet is preferably in the relation of the dye supply layer> the dye transfer contributing layer. Further, it is preferable that the sublimable dye is easily diffused and supplied from the dye supply layer to the dye transfer contributing layer. For the diffusion of the sublimable dye in the dye layer, Fick's law, that is, the amount of the dye dn that has passed the cross-sectional area q at time dt, the density gradient of the dye in the diffusion direction is dc / dx, and D is applied when heat is applied Assuming that the average diffusion coefficient of each part in the dye layer is dn = −D × (dc /
The relationship dx) × q × dt applies. Therefore, as means for facilitating the diffusion and supply of the sublimable dye from the dye supply layer to the dye transfer layer, 1) the relation of the dye supply layer> the dye transfer contributing layer with respect to the dye concentration, and / or 2) Regarding the diffusion coefficient in each layer, the dye supply layer>
The relationship of the dye transfer contributing layer is mentioned, and the above 2)
Can be obtained, for example, by lowering the glass transition point or softening temperature of the organic binder in the dye supply layer.

As the organic binder in the dye supply layer,
The thermoplastic resin exemplified as the organic binder in the above-described dye layer can be used, and the dye transfer contributing layer can be made of a thermoplastic or thermosetting resin,
For example, vinyl chloride resin, vinyl acetate resin, polyamide, polyethylene, polycarbonate, polypropylene, acrylic resin, polyester, polyurethane resin,
Epoxy resin, silicone resin, fluorine resin, polyvinyl acetal resin, polyvinyl alcohol, cellulose resin, natural rubber, synthetic rubber, and the like can be used. One of these resins may be used, but a plurality of them may be mixed or a copolymer of these may be used. Further, from the viewpoint of adhesiveness to the dye supply layer, it is preferable to use a resin having good compatibility with the resin of the dye supply layer, and it is particularly desirable to use the same kind of resin as the resin of the dye supply layer. When resins that are incompatible with each other are used, peeling may occur between the dye supply layer and the dye transfer contributing layer.

When the resin in the dye transfer contributing layer has active hydrogen, heat resistance can be improved by reacting with an isocyanate compound and thermally curing the resin, preventing fusion with the image receiving sheet. Further, a recorded image free from image unevenness can be obtained. Examples of the isocyanate compound used here include tolylene diisocyanate and 4,4-aromatic isocyanate.
Diphenylmethane diisocyanate, triphenylmethane triisocyanate, adducts of tolylene diisocyanate with trimethylolpropane, tolylene diisocyanate trimer, and the like.Examples of aliphatic or alicyclic isocyanates include hexamethylene diisocyanate, dicyclohexylmethane diisocyanate, and isophorone diisocyanate. , Trimethylhexamethylene diisocyanate, 1,6,11-undecane triisocyanate, lysine diisocyanate, lysine ester triisocyanate, 1,8-diisocyanate-4-isocyanatomethyloctane, 1,3,6-hexamethylene triisocyanate bicycloheptane Triisocyanates and various isocyanates such as modified products or derivatives thereof. And the like. Commercial products include Takenate D-102, Takenate D-103, Takenate D-104, Takenate D-103H, Takenate D-104N, Takenate D-106N, Takenate D
-110N, Takenate D-120N, Takenate D-
202, Takenate D-204, Takenate D-21
5, Takenate D-217, Takenate D-212M
6, Takenate D-165NCX, Takenate D-17
0N, Takenate D-181N, Staphyloid TDH
103, 113, and 703 (all manufactured by Takeda Pharmaceutical Co., Ltd.).

When a resin having active hydrogen in the dye transfer contributing layer is reacted with an isocyanate compound,
The molar ratio of the —NCO group of the isocyanate compound and the active hydrogen group of the resin is preferably 0.1 to 10, and 0.3 to 0.3.
It is particularly preferable that it is 0.7. As the isocyanate compound, those having a lower reaction rate are preferable from the viewpoint of the pot life of the coating liquid, and aliphatic or alicyclic isocyanate compounds, particularly aliphatic isocyanate compounds having a hydrophilic group are used in an alcohol-based solvent. Is preferred.

In the case where the glass transition point or the softening temperature of the organic binder is different between the dye supply layer and the dye transfer contributing layer, the glass transition temperature is 0 ° C. or less, or the softening temperature is 60 ° C. or less. It is preferable to use a resin or a natural or synthetic rubber.
0,1000, manufactured by Meisei Chemical Co., Ltd.) and caprolactone polyol (Placcel H-1,4,7, manufactured by Daicel Chemical Industries, Ltd.) are practically useful. Using one or more of these and the thermoplastic or thermosetting resin in a mixed form, the glass transition point or softening temperature of the organic binder in the dye supply layer is lower than that in the dye transfer contributing layer. Can be.

Further, from the viewpoint of preventing ghost during color superposition, it is preferable to provide a low-dyeing resin layer mainly composed of a resin as an organic binder on the uppermost layer of the dye layer in the sublimation type thermal transfer member. As the resin used for the low-dyeing resin layer, a target resin is evaluated as a resin for an image receiving layer of an image receiving sheet, and a resin having a low recording image density in sublimation type thermal transfer recording is suitable. The evaluation as to whether or not the resin is suitable as the resin used for the low-dyeing resin layer can be specifically performed by the following method.

That is, first, 5 to 20% by weight of each resin to be examined is dissolved in a volatile solvent, and 30 wt.
t% modified silicone oil SF8411 / SF842
Each of the resin solutions obtained by adding 7 = 1/1 (manufactured by Toray Silicone Co., Ltd.) was applied to synthetic paper YUPO FPG # 95 (manufactured by Oji Yuka Co., Ltd.) so that the film thickness after drying was 10 μm, and 70 ° C. After drying for one minute, each image receiving sheet is further dried at room temperature for one day or more. Next, using each of the produced image receiving sheets, an image receiving sheet and a Mitsubishi color video processor SCT-
A thermal sheet KMT-85-6MPD4 having a resolution of 6 dots / mm and an average resistance of 542Ω, with a color sheet for CP200 (cyan sublimation type thermal transfer material) superimposed.
(Manufactured by Kyocera) and recorded at 2.00 mj / dot,
The density of the image recorded on each image receiving sheet is measured with a reflection type densitometer RD-918, and a resin having a recorded image density of 1.2 or less, particularly 1.0 or less is adopted as a resin of the low dyeing resin layer. Is preferred.

Preferred resins for the low-dyeing resin layer include, for example, aromatic polyester resins, styrene-butadiene resins, polyvinyl acetate resins, polyamide resins,
Further, particularly preferred resins include methacrylate resins or copolymers thereof, styrene maleate copolymers, polyimide resins, silicone resins, styrene acrylonitrile resins, polysulfone resins, and the like. The thickness of the low-dyeing resin layer is 0.05 to 5 μm.
Is suitable, and 0.1 to 2 μm is preferable. Known additives such as a releasing agent and an antioxidant can be added to the dye layer, the dye supply layer, the dye transfer contributing layer or the low dyeing resin layer.

The thermal transfer recording method using the sublimation type thermal transfer member of the present invention may be either a one-time recording method or a multiple recording method. A multiple recording method using a speed difference mode method of forming a recorded image on an image receiving sheet as> 1) is preferable in that the running cost can be reduced. In the thermal transfer recording method, as a heat application method for heating the sublimation type thermal transfer body adhered to the image receiving sheet in an image-like manner,
A method using a thermal head, a hot stamping plate, a laser beam, or Joule heat generated in a support can be used. The energetic thermal transfer method using Joule heat is described in, for example, U.S. Pat. No. 4,103,066, and JP-A-57-14.
060, JP-A-57-11080 and JP-A-59-9096.

When the sublimation type thermal transfer body of the present invention is used in the energized thermal transfer method, polyester, polycarbonate, triacetyl cellulose, which has good heat resistance, is used as a support.
Nylon, polyimide, resin such as aromatic polyamide aluminum, copper, iron, tin, zinc, nickel molybdenum,
A support in which a metal powder such as silver and / or a conductive powder such as carpon flux is dispersed to adjust the resistance value to an intermediate value between an insulator and a good conductor, or a support in which a conductive metal is deposited or sputtered on the resin sheet. You can use your body.
The thickness of these supports is preferably about 2 to 15 μm in consideration of Joule heat conduction efficiency. Also,
When laser light is used as the heat application method, a material that absorbs laser light and generates heat may be selected as the support.
For example, a laser light absorbing agent such as carbon may be contained in the resin sheet, or a resin sheet having a laser light absorbing layer formed on the front or back surface of the resin sheet may be used.

The image receiving sheet is preferably a sheet having an image receiving layer formed on a substrate. Substrates include synthetic paper, woodfree paper,
Art paper, coated paper, cellulose fiber paper, or films or sheets of various plastics such as polyolefin, polyethylene terephthalate, and polycarbonate can be used.Furthermore, various plastics are formed by adding a white pigment or a filler to the film. A white opaque film or a foamed foam sheet can also be used.
In addition, a laminate of the above-mentioned substrate can also be used, and typical examples thereof include a laminate of cellulose fiber paper and synthetic paper, a laminate of cellulose fiber paper and plastic film, and a laminate of plastic film and synthetic paper. The thickness of the substrate may be arbitrarily determined, and for example, is generally about 10 to 300 μm. Further, it is preferable to subject the surface of the substrate to a primer treatment or a corona discharge treatment as necessary to improve the adhesive strength to the image receiving layer.

The image receiving layer is a layer for receiving and maintaining a sublimable dye transferred from the sublimation type thermal transfer member by heating, and is a layer mainly composed of a resin. Examples of the resin used in the image receiving layer include polyolefin resins such as polypropylene, halogenated polymers such as polyvinyl chloride and polyvinylidene chloride, vinyl polymers such as polyvinyl acetate and polyacrylic ester, and polyesters such as polyethylene terephthalate and polybutylene terephthalate. Resins, polystyrene resins, polyamide resins, cellulose resins, polycarbonate resins, and the like. Particularly preferred are vinyl resins, polycarbonate resins, and polyester resins. If necessary, modified or unmodified silicone oil, release agents such as fluorine-type additives, pigments such as titanium oxide, zinc oxide, calcium carbonate, and finely divided silica, ultraviolet absorbers, antioxidants, etc. May be added. The thickness of the image receiving layer is suitably from 1 to 50 μm, and preferably from 2 to 5 μm.

When recording is performed a number of times by the speed difference mode method using such an image receiving sheet and the sublimation type thermal transfer member of the present invention, the image receiving sheet and the sublimation type thermal transfer member are subjected to heat fusion, sticking, and dye layer formation. In order to better prevent peeling and obtain a recorded image with excellent image quality, the gel fraction of the image receiving layer is preferably set to 70 to 99% by weight,
It is particularly preferred that the content be 90 to 99% by weight. When the gel fraction is less than 70% by weight, heat fusion occurs and it is difficult to perform normal recording by the speed difference mode method. When the gel fraction exceeds 99% by weight, heat fusion does not occur but recording sensitivity is low. It becomes. The gel fraction is defined as 50 mm × 1 of the image receiving sheet.
A small piece of 00 mm was used as a sample, and this was immersed in 500 g of a methyl ethyl ketone solvent (a good solvent for the resin of the image receiving layer) for 10 minutes.

In order to form an image-receiving layer that achieves the above-mentioned gel fraction, generally known curable resins and resins having active hydrogen and those which form a cured reactant such as isocyanate compounds may be used. , Polypropylene, acrylic resin, polyester, polycarbonate, polyurethane, epoxy resin, silicone resin, melamine resin, natural rubber, synthetic rubber, polyvinyl alcohol, cellulose resin and the like.
They may be used alone or as a mixture of two or more thereof, or may be used as a polymer thereof. In particular, a polyester and a vinyl chloride / vinyl acetate copolymer resin are preferred because they have excellent dyeing properties with a sublimable dye, and furthermore can react with an isocyanate compound under a catalyst to obtain an image-receiving sheet having an appropriate gel fraction.

Specifically, polyesters such as Byron 200, Byron 300, Byron 500, and GV-1
10, GV-230, UR-1200, UR-230
0, EP-1012, EP-1032, DW-250
H, DX-750H, DY-150H, etc. (all manufactured by Toyobo Co., Ltd.). Examples of vinyl chloride / vinyl acetate copolymer resins include VYHH, VYNS, VYHD, VYLF,
VMCH, VMCC, VAGH, VROH, etc. (all manufactured by Union Carbide) or Denka Vinyl # 1000A,
1000MT, 1000D, 1000L, 10
00CK2, 1000GKT and the like (all manufactured by Denki Kagaku).

As the isocyanate compound, those described above as the isocyanate compound used for forming the dye transfer contributing layer can be used. As the addition amount of the isocyanate compound, a ratio of the NCO group of the isocyanate compound / the OH group of the resin having active hydrogen of 0.1 / 1 to 1/1 is appropriate. In order to form an image receiving layer having a cured reaction product of a resin having active hydrogen and an isocyanate compound, not only is the image receiving layer coating liquid applied and dried, but also after drying, it is allowed to stand in a high-temperature atmosphere for a long time. The aging temperature is preferably 50 ° C. to 15 ° C. from the viewpoint of preventing the image receiving sheet from curling during aging.
0 ° C. is appropriate, and 60 ° C. to 100 ° C. is preferable.

Examples of the catalyst for the reaction between a resin having active hydrogen and an isocyanate compound include amine catalysts such as dimethylmethanolamine, diethylcyclohexylamine, triethylamine, N, N-dimethylpiperazine and triethylenediamine, and cobalt naphthenate and octene. Metals such as lead acid, dibutyltin dilaurate, stannous chloride, stannic chloride, tetra-n-butyltin, tri-n-butyltin acetate, di-n-butyltin oxide, di-n-octyltin oxide And a tin catalyst is particularly preferable. Specifically, TK1L (manufactured by Takeda Pharmaceutical Co., Ltd.), Scat1, 1L, 8, 10, and 71
L, StannBL (all manufactured by Sankyo Seiki Co., Ltd.) and the like. The amount of the catalyst to be added is 0.05 to
1.3% by weight is preferred. If the amount is too small, the curing promoting effect is low, and an image receiving layer having sufficient heat resistance cannot be obtained.

It is preferable that at least one of an antioxidant, a light stabilizer and an ultraviolet absorber is added to the image receiving layer.
The content is preferably 5 to 10 parts by weight, and a total amount of 30% by weight or less.
However, when a protective layer containing an ultraviolet absorber is provided on the image receiving layer, the image receiving layer may or may not contain the ultraviolet absorber. As the antioxidant, commercially available general agents can be used, and examples thereof include amine-based antioxidants, mono- or bis-polymer phenol-based antioxidants, sulfur-based antioxidants, hydroquinone-based antioxidants, and guanidine derivatives. Specifically, N, N′-diphenyl-1,4-phenylenediamine, phenyl-β-naphthylamine, 2,6-di-t-butyl-β-cresol, 4,4′-butylidene-bis (3- Methyl-6-butyl-phenol), tetrakis- [methylene-3-
(3 ', 5'-di-t-butyl-4'-hydroxyphenyl) propionate], 2-mercaptobenzothiazole, 2,5'-di-t-butylhydroquinone, 1,3
-Dicyclohexyl-2- (2 ', 5'-dichlorophenyl) quanidine and the like.

As the light stabilizer, commercially available general ones can be used. Hindered amine-based and hindered phenol-based antioxidants are suitable, and tertiary amine-based light stabilizers which do not react with the isocyanate compound are suitable. Preferably, specifically, Adekastab LA-82, Adekarkurs DN-44M (manufactured by Asahi Denka Kogyo), Sanol LS
-765 (manufactured by Sankyo). Commercially available ultraviolet absorbers include, for example, hydroxybenzophenone, dihydroxybenzophenone and the like, and benzotriazole-based or hindered amine-based and salicylic acid derivatives. Specific examples thereof include TinuvinP.
(Manufactured by Ciba-Geigy Corporation), 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2- (2′-hydroxy-3 ′, 5′-di-t)
-Butylphenyl) -5-chlorobenzotriazole,
2- (2-hydroxy-3,5-di-t-alphenyl) -2H-benzotriazole, 2- (2'-hydroxy-3'-t-butyl-5'-methylphenyl) -5
Chlorobenzotriazole and the like can be mentioned.

[0073]

According to the sublimation-type thermal transfer member of the present invention, a recorded image having a constant hue over the entire density range of an image is formed on an image receiving sheet without causing a hue shift between a medium-low density portion and a high density portion. Can be formed. Further, according to the sublimation-type thermal transfer body of the present invention, the density of the recorded image does not decrease even when it is repeatedly used many times, and the hue is always constant irrespective of the number of recordings, and the hue is constant over the entire density range. A certain recorded image can be formed on the image receiving sheet.

The present inventors have studied the causes of the hue shift between the middle and low density parts and the high density part, and have obtained the following findings. That is, first, a first dye layer composed of two or more kinds of sublimable dyes having different hues having a predetermined dye mixing ratio is formed on a support, and then a second dye layer is formed on the first dye layer. Are laminated, the sublimable dye in the first dye layer elutes into the second dye layer according to the solubility of the second dye layer coating solution in the solvent. The solubility of the sublimable dye in the first dye layer in the solvent of the second dye layer coating liquid is different for each sublimable dye. The dye compounding ratio of the sublimable dye in the dye layer is 2 when the sublimable dye in the first dye layer is eluted into the second dye layer.
This is significantly different from the predetermined dye compounding ratio when the dye coating solution for the layer is prepared.

As described above, when thermal transfer recording is performed using a sublimation type thermal transfer member having a different dye mixing ratio between the upper layer (second layer) and the lower layer (first layer) in the dye layer, the sublimation type thermal transfer member is transferred to the image receiving layer. In the diffusion of the sublimable dye (image formation by transfer of the sublimable dye to the image receiving layer), the diffusion distance of the sublimable dye is finite according to the applied thermal energy, and the energy is low (the image in the middle and low density area is formed). ), The diffusion distance is short, and as a result, only the sublimable dye in the upper layer (second layer) in the dye layer is transferred to the image receiving layer. On the other hand, when the energy is high (an image of a high density portion is formed), the diffusion distance is long, and consequently the sublimable dyes of the lower layer (first layer) and the upper layer (second layer) are simultaneously formed in the dye layer. Move to. As a result, when the dye composition ratio of the upper layer (second layer) and the lower layer (first layer) in the dye layer is different, the mixing ratio of the sublimable dye transferred to the image receiving layer in the middle and low density parts and the high concentration part In the composition ratio of the sublimable dye transferred to the image receiving layer will be significantly different,
As a result, it was found that in a sublimation-type thermal transfer member having a dye layer having a laminated structure containing two or more kinds of sublimable dyes having different hues, a hue shift occurred between a high density portion and a middle / low density portion of a recorded image.

To explain this more specifically, if a sublimable dye having several different hues, for example, a first dye layer composed of a magenta dye composed of a red dye and a violet dye is formed, When laminating the second dye layer on the first dye layer, if the solubility of the violet dye in the solvent of the second dye layer coating solution is larger or smaller than the solubility of the red dye, The dye compounding ratio of the sublimable dye in the second dye layer is a dye compounding ratio with more or less violet dye compared to the initial dye compounding ratio when the second dye layer coating solution was prepared, The middle and low density portions of the recorded image have a biolett color rich (purple magenta) or biolett color poor (reddish magenta) hue as compared with the high density portion.

As the solvent for the dye layer coating solution for forming the dye layer having the above-mentioned laminated structure, a conventionally known solvent that dissolves and disperses a sublimable dye, an organic binder and the like can be used. As a solvent for regulating the solubility of the sublimable dye in order to prevent the dye compounding ratio from differing, it is preferable to use a solvent for the upper layer dye layer coating solution from the above reasons. However, in general, when a mixed system of several kinds of solvents is used as a solvent for a dye layer coating liquid, the solvent composition changes with time due to a difference in evaporation rate and the like. Toluene, which is the most versatile solvent as a dye layer coating liquid solvent for a sublimation-type thermal transfer member, and is an aromatic solvent since the sublimable dye is generally an aromatic-containing disperse dye or an oil-soluble dye. It is preferable to use

The present invention has been made on the basis of such findings, and is directed to a sublimation-type thermal transfer material having a laminated dye layer containing two or more sublimable dyes having different hues on a support. D1, D2, D3... Dn for each hue are the sum of the product of the compounding ratio of each sublimable dye belonging to the same hue in the dye layer and the solubility in toluene.
, For the hue showing the highest value (Dh),
By setting the value in each other hue to 0.5 × Dh or more, or 2) the sum of the product of the mixing ratio of each sublimable dye belonging to the same hue in the dye layer, the solubility in toluene, and the extinction coefficient is obtained. E1, E2, E for each hue
... En, the hue indicating the highest value (Eh) is set to 0.5 × E for each of the other hues.
h) or 3) by making the type of sublimable dye in the upper layer of the laminated dye layer and the compounding ratio thereof equal to the type of sublimable dye in the lower dye layer and the compounding ratio thereof. A recorded image having a constant hue over the entire density range of an image can be formed on an image receiving sheet without causing a hue shift between a low density portion and a high density portion. Further, even when the sublimation type thermal transfer body is used many times, the density of the recorded image does not decrease and the hue is always constant irrespective of the number of recordings, and the hue is constant over the entire density range. Can be formed. This is because the sublimable dyes in the upper layer and the lower layer of the laminated dye layer have no or little imbalance in the hue mixing ratio.

The highest value is obtained when the sum of the product of the mixing ratio of each sublimable dye belonging to the same hue in the dye layer and the solubility in toluene is D1, D2, D3... Dn for each hue. With respect to the hue indicating (Dh), the value in each of the other hues is set to 0.7 × Dh or more, or the mixing ratio of each sublimable dye belonging to the same hue in the dye layer and the solubility in toluene are determined. The sum of the products of the extinction coefficients is E1, E2, E3
... When En, the value in each of the other hues is set to 0.65 × Eh for the hue indicating the highest value (Eh).
By doing so, it is possible to further prevent the occurrence of hue shift between the medium-low density portion and the high density portion, and to form a recorded image having a constant hue over the entire density range of the image on the image receiving sheet. In addition, in a large number of recordings, it is possible to form a recorded image in which the hue is always constant irrespective of the number of recordings and the hue is constant in the entire density range on the image receiving sheet.

In order to prevent the occurrence of hue shift due to the image density in the recorded image, in order to prevent the occurrence of hue shift due to the image density in the sublimation type thermal transfer member having a laminated dye layer containing two or more sublimable dyes having different hues on the support, In addition, it is preferable that the hue mixing ratio of the sublimable dye in the lower dye layer is as close as possible. From the above, the value of each of the other hues is set to 0.5 × Dh or more with respect to the hue having the highest value (Dh) as described above, or the hue having the highest value (Eh) is determined. On the other hand, the value in each of the other hues is preferably 0.5 × Eh or more, and particularly the value in each of the other hues is preferably 0.7 × Dh or 0.65 × Eh.

Further, by adding a sublimable dye having the same hue as the sublimable dye having the lowest solubility in toluene and having the highest solubility in toluene, or adding the same hue as the sublimable dye having the highest solubility in toluene. By adding a sublimable dye having a low solubility in toluene in hue, the imbalance of the elution of the sublimable dye at the time of lamination of the dye layer is corrected, and the hue mixing ratio of the sublimable dye in the upper and lower dye layers is adjusted. By adjusting the balance, a recorded image having a constant hue over the entire density range of the image can be formed on the image receiving sheet. Further, in multiple recording, a recorded image having a constant hue regardless of the number of recordings and a constant hue over the entire density range can be formed on the image receiving sheet.

Further, by adding a sublimable dye having the same hue as the hue of the sublimable dye having the smallest product of the solubility in toluene and the extinction coefficient and having a large product of the solubility and the extinction coefficient in toluene, or By adding a sublimable dye having the same hue as the sublimation dye to which the product of the extinction coefficient belongs to and the product of the solubility in toluene and the extinction coefficient to be small, imbalance in the elution of the sublimable dye when the dye layer is laminated. By adjusting the balance of the hue mixing ratio of the sublimable dye in the upper and lower dye layers, a recorded image having a constant hue over the entire density range of the image can be formed on the image receiving sheet. . Further, in multiple recording, a recorded image having a constant hue regardless of the number of recordings and a constant hue over the entire density range can be formed on the image receiving sheet.

Further, by making the types and the mixing ratios of the sublimable dyes in the upper layer of the laminated dye layer equal to the types and the mixing ratios of the sublimable dyes in the lower dye layer, the number of recordings can be reduced. And the mixing ratio of the sublimable dye transferred from the upper layer to the image receiving sheet, which mainly contributes to the image formation in the recording in the medium and low density areas, Since the mixing ratio of the sublimable dye transferred from the lower layer, which mainly contributes to image formation, to the image receiving sheet is equivalent, no hue shift occurs between the medium-low density portion and the high density portion. A recorded image having a constant hue over the entire density range of the image can be formed on the image receiving sheet, and the hue is always constant irrespective of the number of recordings even if the sublimation-type thermal transfer body is used many times, and Hue is constant over the entire density range The recorded image can be formed on the image receiving sheet that.

In the sublimation type thermal transfer material of the present invention, by using a red dye and a violet dye as two or more sublimable dyes having different hues, the transferability under heat application conditions, the density of the recorded image, and the sharpness of the color. Thus, a sublimation type thermal transfer material for magenta color which satisfies image characteristics such as temperature, high light resistance and high storage stability and does not cause a hue shift in a recorded image can be obtained. Further, by using a blue dye and a green dye as two or more sublimable dyes having different hues, transferability under heat application conditions, density of a recorded image, color clarity,
It is possible to obtain a sublimation type thermal transfer material for cyan which satisfies image characteristics such as high light fastness and high storage stability and does not cause a hue shift in a recorded image.

Further, by using a yellow dye, a magenta dye and a cyan dye as two or more kinds of sublimable dyes having different hues, transferability under heat application condition, density of recorded image, sharpness of color, high light fastness can be obtained. A sublimation type thermal transfer body for black which satisfies image characteristics such as storability and high storage stability and does not cause a hue shift in a recorded image can be obtained. The sublimation-type thermal transfer member for forming a black image has a large change in hue due to the number of recordings, particularly in a low-density portion or a high-density portion, or a horizontal thin line of a character. It is possible to obtain a black recorded image in which the hue does not change in the entire density range of the image or the horizontal thin line of the character.

[0086]

The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the invention is limited thereto. All parts are parts by weight.

Example 1 4 μm having a 1 μm thick silicone resin heat-resistant layer on the back surface
The lower dye layer coating solution having the following composition was applied to the surface of a polyethylene terephthalate film having a thickness of 0.5 μm using a wire bar and dried at 100 ° C. for 90 seconds to form a lower dye layer having a thickness of 0.5 μm. An upper layer dye layer coating solution having the following composition was applied thereon and dried at 100 ° C. for 90 seconds to form an upper layer dye layer having a thickness of 0.5 μm to obtain a sublimation type thermal transfer member for one-time recording. [Lower Dye Layer Coating Solution] Red sublimable dye (HM1041, manufactured by Mitsui Toatsu Chemicals, Inc.) 3.5 parts Violet sublimable dye (Macrolex Red Vioret R, manufactured by Bayer AG) 2 parts Violet sublimable dye ( HS0147, manufactured by Mitsui Toatsu Chemicals) 1.5 parts Polyvinyl butyral (BX-1, manufactured by Sekisui Chemical) 5 parts Toluene 35 parts Methyl ethyl ketone 35 parts Dioxane 25 parts [Upper layer dye layer coating solution] Sublimable dye: Lower layer dye The amount obtained by multiplying the sublimable dye of the layer coating solution by 0.7 each Polyvinyl butyral (BX-1, manufactured by Sekisui Chemical Co., Ltd.) 5 parts Toluene 47.5 parts Methyl ethyl ketone 47.5 parts

Examples 2 to 3 Sublimation dyes for one-time recording were prepared in the same manner as in Example 1 except that the sublimable dye shown in Table 1 was used in place of the sublimable dye in Example 1 in parts by weight shown in Table 1. A thermal transfer member was obtained.

Comparative Example 1 A one-time recording sublimation type thermal transfer material was used in the same manner as in Example 1 except that the sublimable dye shown in Table 1 was used in place of the sublimable dye in Example 1 in parts by weight shown in Table 1. I got

In each of the sublimation-type thermal transfer members of Examples 1 to 3 and Comparative Example 1, the solubility X of each florescent dye in toluene was determined.
(G / l), the product Y of the compounding ratio of each sublimable dye belonging to the same hue and the solubility in toluene, and the product Y of the compounding ratio of each sublimable dye belonging to the same hue and the solubility in toluene. Value D, product W (× 10 ³ ) of the blending ratio of each sublimable dye belonging to the same hue, the solubility in toluene and the extinction coefficient, the blending ratio of each sublimable dye belonging to the same hue, the solubility in toluene and the extinction coefficient Table 1 shows a value E (× 10 ³ ) obtained by summing the products W of.

[0091]

[Table 1]

Example 4 6 μm having a 1 μm thick heat-resistant silicone resin layer on the back surface
The intermediate adhesive layer coating solution having the following composition is applied to the surface of an aromatic polyamide film having a thickness of 1 m using a wire bar, dried at 100 ° C for 90 seconds, and then subjected to an aging treatment at 60 ° C for 12 hours to form a 1 µm thick intermediate adhesive. A layer was formed. next,
Using a wire bar, a dye supply layer coating solution, a dye transfer contributing layer coating solution and a low dyeing resin layer coating solution having the following composition are sequentially applied on the intermediate adhesive layer, and dried at 100 ° C. for 90 seconds to be laminated. Subsequent aging treatment at 60 ° C. for 12 hours, sublimation thermal transfer for multiple recordings having a 4.5 μm thick dye supply layer, a 0.5 μm dye transfer contributing layer, and a 0.7 μm low dyeing resin layer. I got a body. [Intermediate adhesive layer coating liquid] Polyvinyl butyral resin (BX-1, manufactured by Sekisui Chemical Co., Ltd.) 10 parts Isocyanate compound (Coronate L, manufactured by Nippon Polyurethane Co., Ltd.) 5 parts Toluene 95 parts Methyl ethyl ketone 95 parts [Dye supply layer coating liquid Polyvinyl butyral resin (BX-1, manufactured by Sekisui Chemical Co., Ltd.) 10 parts Yellow sublimable dye (Y2, manufactured by Nippon Kayaku Co., Ltd.) 10 parts Magenta sublimable dye (SMS8, manufactured by Nippon Kayaku Co., Ltd.) 10 parts Cyan Sublimation dye (CY6, manufactured by Nippon Kayaku Co., Ltd.) 8 parts Cyan-based sublimation dye (MSCyanVPG, manufactured by Mitsui Toatsu Chemicals, Inc.) 6 parts Ethanol 180 parts Positive butanol 10 parts [Dye transfer contributing layer coating liquid] Polyvinyl Butyral resin (BX-1, manufactured by Sekisui Chemical) 10 parts Isocyanate compound (Coronate L, manufactured by Nippon Polyurethane) 5 parts D Nol 180 parts Positive butanol 10 parts [Coating solution for low-dyeing resin layer] Styrene-maleic acid copolymer (trade name: Suprapearl AP-30 manufactured by BASF) 5 parts A liquid below 20 parts Positive butanol 20 parts A liquid Preparation 15 g of dimethylmethoxysilane and 9 g of methyltrimethoxysilane were mixed with 12 g of toluene and 1 g of methyl ethyl ketone.
It was dissolved in a mixed solution with 2 g, and 13 ml of 3% sulfuric acid was added to carry out hydrolysis for 3 hours.

Examples 5 to 8 Sublimation dyes for multiple recordings were prepared in the same manner as in Example 4 except that the sublimable dye shown in Table 2 was used in place of the sublimable dye in Example 4 in parts by weight shown in Table 2. A thermal transfer member was obtained.

Comparative Examples 2 to 4 Sublimation dyes for multiple recordings were prepared in the same manner as in Example 4 except that the sublimable dyes shown in Table 2 were used in place of the sublimable dyes in Example 4 in parts by weight shown in Table 2. A thermal transfer member was obtained.

The solubility X (g / l) of each of the sublimable dyes in toluene in the sublimation-type thermal transfer materials of Examples 4 to 8 and Comparative Examples 2 to 4, the mixing ratio of each sublimable dye belonging to the same hue and the ratio to toluene The product Y of the solubility, the sum D of the product Y of the blending ratio of each sublimable dye belonging to the same hue and the solubility in toluene, the blending ratio of each sublimable dye belonging to the same hue, the solubility in toluene and the absorbance indicates the coefficient of the product W (× 10 ^3), the values were the sum of the products W solubility and absorption coefficient for the mixing ratio of toluene each sublimable dye belonging to the same hue E (× 10 ³⁾ in Table 2 and Table 3 .

[0096]

[Table 2]

[0097]

[Table 3]

Next, an image-receiving layer coating solution having the following composition was applied on synthetic paper (Yupo FPG # 150, manufactured by Oji Oil Chemicals Co., Ltd.) and dried to form an image-receiving layer having a thickness of 6 μm. Was obtained. [Image receiving layer coating liquid] Vinyl chloride / vinyl acetate / vinyl alcohol copolymer (trade name VAGH manufactured by Union Carbide) 15 parts Alcohol-modified silicone oil (trade name SF8427 manufactured by Toray Silicone Co.) 1 part Toluene 40 parts Methyl ethyl ketone 40 parts

An image receiving layer coating solution having the following composition was applied to synthetic paper (Yupo FPG # 150, manufactured by Oji Yuka Co., Ltd.), dried, and then heated at 60 ° C. for 50 hours to obtain a thickness. An image receiving layer having a thickness of 6 μm was formed to obtain an image receiving sheet for recording many times. [Coating solution for image receiving layer] Vinyl chloride / vinyl acetate / vinyl alcohol copolymer (product name VAGH manufactured by Union Carbide) 15 parts Isophorone diisocyanate adduct (product name D-140N manufactured by Takeda Pharmaceutical Company) 5 parts Tin catalyst (Takeda Chemical Co., Ltd.) 0.1 parts unmodified silicone oil (trade name: SH200, manufactured by Toray Silicone, kinematic viscosity: 1000 cs) 0.5 parts Alcohol-modified silicone oil (trade name: SF8427, manufactured by Toray Silicones) 0.5 part 40 parts of toluene 40 parts of methyl ethyl ketone

Using the one-time recording sublimation-type thermal transfer body and the one-time recording image-receiving sheet obtained above, the upper dye layer of the sublimation-type thermal transfer body is brought into contact with the image-receiving layer of the image-receiving sheet. Superimposition, or sublimation type thermal transfer body for multiple times recording and image receiving sheet for multiple times recording, the upper dye layer of the sublimation type thermal transfer body and the image receiving layer of the image receiving sheet are overlapped so as to be in contact with each other, and the sublimation type thermal transfer body A gradation pattern image (a pattern image in which the density is gradually changed from low density to high density) is recorded under the following conditions by applying heat from the back surface of the support with a thermal head, and the recorded image is formed on the image receiving layer of the image receiving sheet. Was formed. Thermal head resolution 12 dots / mm Applied power 0.16 W / dot (recording many times) 0.12 W / dot (one-time recording) Running speed of image receiving sheet 8.4 mm / sec Running speed of sublimation type thermal transfer body 0.6 mm / Sec (multiple recording: N = 14) 2.8 mm / sec (multiple recording: N = 3) 8.4 mm / sec (one-time recording)

One-time recording or multiple recording (N = 1
The hue shift between the high density portion and the low density portion of the recorded image (gradation pattern image) in 4) was visually evaluated. Further, the hue shift in the low density portion of the recorded image (gradation pattern image) in the multiple recording (N = 3) and the multiple recording (N = 14) is visually evaluated, and the hue shift is accompanied by the number of recordings in the low density portion. Hue shift was evaluated. The results are shown in Tables 4, 5 and 6.

[0102]

[Table 4]

[0103]

[Table 5]

[0104]

[Table 6]

As is evident from the results in Tables 4, 5 and 6, the use of the sublimation type thermal transfer member of the example was compared with the case of using the sublimation type thermal transfer member of the comparative example, in which one-time recording or recording was performed. Hue misregistration did not occur between the low-density part and the high-density part when recording N = 14 a large number of times, and a recorded image was obtained in which the hue was constant over the entire density range of the image. Further, when the sublimation type thermal transfer member of the example was used, the number of recordings N = 3 was larger than that in the case where the sublimation type thermal transfer member of the comparative example was used.
No or little hue shift occurred in the low-density portion at N = 14, and a recorded image was obtained in which the hue was constant over the entire density range of the image regardless of the number of recordings.

Example 9 The following intermediate adhesive layer coating solution was applied to the surface of a 6 μm-thick aromatic polyamide film having a 1 μm-thick silicone resin-based heat-resistant layer on the back surface using a wire bar, and dried to obtain a thick film. 3. An intermediate adhesive layer having a thickness of 1.0 μm is formed, and the following dye supply layer coating solution is applied on the intermediate adhesive layer and dried to obtain a thickness of 4.
A dye supply layer of 0 μm was formed. Next, the following dye transfer contributing layer coating solution is applied on the dye supply layer using a wire bar, and dried to form a dye transfer contributing layer having a thickness of 1.0 μm, followed by heat curing at 60 ° C. for 12 hours. Thus, a magenta sublimation type thermal transfer member was prepared. [Intermediate adhesive layer coating liquid] Polyvinyl butyral resin (BX-1, manufactured by Sekisui Chemical Co., Ltd.) 10 parts Diisocyanate (Coronate L, manufactured by Nippon Polyurethane Co., Ltd.) 5 parts Solvent Toluene 95 parts Methyl ethyl ketone 95 parts [Dye supply layer coating liquid] Polyvinyl butyral resin (BX-1, manufactured by Sekisui Chemical Co., Ltd.) 7 parts Polyethylene oxide (Alcox R400, manufactured by Meisei Chemical Co., Ltd.) 3 parts Diisocyanate (Coronate L, manufactured by Nippon Polyurethane Co., Ltd.) 3 parts Sublimable dye HSR2164 (manufactured by Mitsubishi Chemical Corporation) 12 parts (Toluene solubility 25 g / l) Macrolex Red Violet R (manufactured by Bayer) 18 parts (toluene solubility 26 g / l) Solvent Ethyl alcohol 170 parts n-butyl alcohol 20 parts [Dye transfer contributing layer coating solution] polyvinyl butyral Tree (BL-S, manufactured by Sekisui Chemical Co., Ltd.), 10 parts of diisocyanate (Coronate L, manufactured by Nippon Polyurethane Co., Ltd.) 3 parts solvent toluene 190 parts

Example 10 The following dye supply layer coating solution was applied onto the intermediate adhesive layer of Example 9 and dried to form a dye supply layer having a thickness of 4.0 μm. Next, the following dye transfer contributing layer coating solution is applied on the dye supply layer and dried to form a dye transfer contributing layer having a thickness of 1.0 μm, and the following low-dyeing resin layer is formed on the dye transfer contributing layer. The coating liquid was applied and dried to form a 0.7 μm-thick low-dyeing resin layer, and then heat-cured at 60 ° C. for 12 hours to prepare a black sublimation-type thermal transfer member. [Dye supply layer coating liquid] Polyvinyl butyral resin (BX-1, manufactured by Sekisui Chemical Co., Ltd.) 7 parts Polyethylene oxide (Alcox R400, manufactured by Meisei Chemical Co., Ltd.) 3 parts Diisocyanate (Coronate L, manufactured by Nippon Polyurethane Co., Ltd.) 3 parts Sublimation Hydrophobic dye HSO-144 (manufactured by Mitsui Toatsu Chemicals) 15 parts (Ethyl alcohol solubility 3 g / l) Macrolex Yellow 6G (manufactured by Bayer) 7.5 parts (ethyl alcohol solubility 3 g / l) HM-1041 (Mitsui Toatsu) 7.5 parts (Ethyl alcohol solubility 4 g / L) Solvent Ethyl alcohol 170 parts n-butyl alcohol 20 parts [Coating solution for dye transfer contributing layer] Polyvinyl butyral resin (BX-1, manufactured by Sekisui Chemical Co., Ltd.) 10 Part Diisocyanate (Coronate L, Nippon Polyurethanes, Inc.) 3 parts Sublimable dye HSO-144 (manufactured by Mitsui Toatsu Chemicals) 2 parts (ethyl alcohol solubility 3 g / l) Macrolex Yellow 6G (manufactured by Bayer) 1 part (ethyl alcohol solubility 3 g / l) HM-1041 (Mitsui) 1 part (Ethyl alcohol solubility 4 g / L) Solvent Ethyl alcohol 190 parts [Low dyeing resin layer coating solution] Styrene-maleic acid copolymer (Suprapearl AP30, BAS F) 5 parts 6 parts of the following α liquid Solvent 20 parts of ethyl alcohol (Synthesis of hydrolysis product of silane coupling agent) 24 g of diphenyldimethoxysilane and 9 g of vinyltriethoxysilane are dissolved in a mixed solution of 50 g of toluene and 50 g of methyl ethyl ketone, and 10 ml of 1% sulfuric acid is dissolved. In addition, hydrolysis was performed for 3 hours. 150 ml of water and 50 ml of toluene
And worshiped for another hour. After completion, the toluene layer was separated and dried over anhydrous sodium sulfate overnight, and then toluene was distilled off to obtain an oily hydrolysis product. This was diluted to 50% with dioxane. This liquid is referred to as α liquid.

Example 11 The following dye supply layer coating solution was applied on the intermediate adhesive layer of Example 9 and dried to form a dye supply layer having a thickness of 4.0 μm. Next, the following dye transfer contributing layer coating solution is applied on the dye supply layer and dried to form a dye transfer contributing layer having a thickness of 1.0 μm, and the following low-dyeing resin layer is formed on the dye transfer contributing layer. The coating liquid was applied and dried to form a 0.7 μm-thick low-dyeing resin layer, and then heat-cured at 60 ° C. for 12 hours to prepare a black sublimation-type thermal transfer member. [Dye supply layer coating liquid] Polyvinyl butyral resin (BX-1, manufactured by Sekisui Chemical Co., Ltd.) 7 parts Polyethylene oxide (Alcox R400, manufactured by Meisei Chemical Co., Ltd.) 3 parts Diisocyanate (Coronate L, manufactured by Nippon Polyurethane Co., Ltd.) 3 parts Sublimation Sex dye HSO-144 (manufactured by Mitsui Toatsu Chemicals) 15 parts (ethyl alcohol / ethyl acetate (9/1) solubility 19 g / liter) Y-2 (manufactured by Nippon Kayaku) 7.5 parts (ethyl alcohol / acetic acid) Ethyl (9/1) solubility 1 g / l) R-3 (manufactured by Nippon Kayaku) 7.5 parts (ethyl alcohol / ethyl acetate (9/1) solubility 17 g / l) Solvent ethyl alcohol 170 parts n-butyl alcohol 20 parts [Coating liquid for dye transfer contributing layer] Polyvinyl butyral resin (BX-1, manufactured by Sekisui Chemical Co., Ltd.) 10 parts Diisocyanate (C Nate L, manufactured by Nippon Polyurethane Co., Ltd. 3 parts Sublimable dye Y-2 (manufactured by Nippon Kayaku Co., Ltd.) 7.5 parts Solvent Ethyl alcohol / ethyl acetate (9/1) 190 parts [Low dyeing resin layer coating solution Styrene-maleic acid copolymer (Suprapar AP30, manufactured by BAS F) 5 parts α liquid 6 parts Solvent Ethyl alcohol / ethyl acetate (9/1) 20 parts

Example 12 The following dye supply layer coating solution was applied on the intermediate adhesive layer of Example 9 and dried to form a dye supply layer having a thickness of 4.0 μm. Next, the following dye transfer contributing layer coating solution is applied on the dye supply layer and dried to form a dye transfer contributing layer having a thickness of 1.0 μm, and the following low-dyeing resin layer is formed on the dye transfer contributing layer. The coating liquid was applied and dried to form a 0.7 μm-thick low-dyeing resin layer, and then heat-cured at 60 ° C. for 12 hours to prepare a black sublimation-type thermal transfer member. [Dye supply layer coating liquid] Polyvinyl butyral resin (BX-1, manufactured by Sekisui Chemical Co., Ltd.) 7 parts Polyethylene oxide (Alcox R400, manufactured by Meisei Chemical Co., Ltd.) 3 parts Diisocyanate (Coronate L, manufactured by Nippon Polyurethane Co., Ltd.) 3 parts Sublimation Sex dye HSO-144 (manufactured by Mitsui Toatsu Chemicals) 15 parts (ethyl alcohol / ethyl acetate (9/1) solubility 19 g / liter) Y-2 (manufactured by Nippon Kayaku) 7.5 parts (ethyl alcohol / acetic acid) Ethyl (9/1) solubility 1 g / l) R-3 (manufactured by Nippon Kayaku Co., Ltd.) 7.5 parts (ethyl alcohol / ethyl acetate (9/1) solubility 17 g / l) Solvent Ethyl alcohol 170 parts n-butyl Alcohol 20 parts [Dye transfer contributing layer coating liquid] Polyvinyl butyral resin (BX-1, manufactured by Sekisui Chemical Co., Ltd.) 10 parts Diisocyanate (C Nate L, manufactured by Nippon Polyurethane Co., Ltd. 3 parts Sublimable dye Macrolex Yellow 6G (manufactured by Bayer) 7.5 parts (Ethyl alcohol / ethyl acetate (9/1) solubility: 40 g or more / liter) Solvent Ethyl alcohol / ethyl acetate (9 / 1) 190 parts [Low-dyeing resin layer coating liquid] Styrene-maleic acid copolymer (Suprapearl AP30, manufactured by BASF) 5 parts The α liquid 6 parts Solvent Ethyl alcohol / ethyl acetate (9/1) 20 Department

Comparative Example 5 The following dye supply layer coating solution was applied on the intermediate adhesive layer of Example 9 and dried to form a dye supply layer having a thickness of 40 μm.
Next, a dye transfer contributing layer coating solution described below was applied on the dye supply layer using a wire bar and dried to form a dye transfer contributing layer having a thickness of 1.0 μm, and then thermally cured at 60 ° C. for 12 hours. A magenta sublimation type thermal transfer member was prepared. [Dye supply layer coating liquid] Polyvinyl butyral resin (BX-1, manufactured by Sekisui Chemical Co., Ltd.) 7 parts Polyethylene oxide (Alcox R400, manufactured by Meisei Chemical Co., Ltd.) 3 parts Diisocyanate (Coronate L, manufactured by Nippon Polyurethane Co., Ltd.) 3 parts Sublimation Sex dye HM-1041 (manufactured by Mitsui Toatsu Chemicals) 7.5 parts (toluene solubility 97 g / l) Macrolex Red Violet R (manufactured by Bayer) 18 parts (toluene solubility 26 g / l) Solvent Ethyl alcohol 170 parts n-butyl Alcohol 20 parts [Dye transfer contributing layer coating liquid] Polyvinyl butyral resin (BL-S, manufactured by Sekisui Chemical Co., Ltd.) 10 parts Diisocyanate (Coronate L, manufactured by Nippon Polyurethane Co., Ltd.) 3 parts Solvent toluene 190 parts

Comparative Example 6 The following dye supply layer coating solution was applied on the intermediate adhesive layer of Example 1 and dried to form a dye supply layer having a thickness of 4.0 μm. Next, the following dye transfer contributing layer coating solution is applied on the dye supply layer and dried to form a dye transfer contributing layer having a thickness of 1.0 μm, and the following low-dyeing resin layer is formed on the dye transfer contributing layer. The coating liquid was applied and dried to form a 0.7 μm-thick low-dyeing resin layer, and then heat-cured at 60 ° C. for 12 hours to prepare a black sublimation-type thermal transfer member. [Dye supply layer coating liquid] Polyvinyl butyral resin (BX-1, manufactured by Sekisui Chemical Co., Ltd.) 7 parts Polyethylene oxide (Alcox R400, manufactured by Meisei Chemical Co., Ltd.) 3 parts Diisocyanate (Coronate L, manufactured by Nippon Polyurethane Co., Ltd.) 3 parts Sublimable dye HSO-144 (manufactured by Mitsui Toatsu Chemicals) 15 parts (ethyl alcohol / ethyl acetate (9/1) solubility 19 g / liter) Y-2 (manufactured by Nippon Kayaku Co., Ltd.) 7.5 parts (ethyl alcohol / Ethyl acetate (9/1) solubility 1 g / l) R-3 (manufactured by Nippon Kayaku) 7.5 parts (ethyl alcohol / ethyl acetate (9/1) solubility 17 g / l) Solvent ethyl alcohol 170 parts n-butyl Alcohol 20 parts [Dye transfer contributing layer coating liquid] Polyvinyl butyral resin (BX-1, manufactured by Sekisui Chemical Co., Ltd.) 10 parts Diisocyanate (C Ronate L, manufactured by Nippon Polyurethane Co., Ltd. 3 parts Solvent Ethyl alcohol / ethyl acetate (9/1) 190 parts [Coating solution for low dyeing resin layer] Styrene-maleic acid copolymer (Suprapearl AP30, manufactured by BAS F) 5 parts The above-mentioned α liquid 6 parts Solvent Ethyl alcohol / ethyl acetate (9/1) 20 parts Also, a mixture having the following composition is sufficiently mixed and dispersed to prepare a coating liquid for the image receiving layer, and the coating liquid has a thickness of about 150 μm. On a synthetic paper (Yupo FPG-150, manufactured by Oji Yuka Synthetic Paper Co., Ltd.) using a wire bar, dried at a drying temperature of 75 ° C. for 1 minute, further stored at 80 ° C. for 3 hours, cured and cured. An image receiving layer having a thickness of about 5 μm was formed to form an image receiving sheet. [Image-receiving layer coating solution] Vinyl chloride / vinyl acetate / vinyl alcohol copolymer 10 parts (YAGH, manufactured by Union Carbide Co.) Diisocyanate (Coronate L, manufactured by Nippon Polyurethane Co., Ltd.) 5 parts Amino-modified silicone 0.5 part (SF8417, Epoxy-modified silicone 0.5 part (SF8411, manufactured by Toray Dow Corning) Solvent Toluene 40 parts Methyl ethyl ketone 40 parts

Using the sublimation type thermal transfer member and the image receiving sheet prepared as described above, a recording test was carried out a number of times as follows at a thermal head resolution of 12 dots / mm and an applied power of 0.16 W / dot. went. 1) Using the sublimation-type thermal transfer body of Example 9 and the above-mentioned image-receiving sheet, the low-density to high-density-mode method (conveyance speed of the sublimation-type thermal transfer body and the image-receiving sheet = 8.4 mm / sec) Printing of a pattern image having 11 tones was repeated seven times using the same portion of the sublimation type thermal transfer member. The same printing was performed using the sublimation type thermal transfer body of Comparative Example 5. Table 7 shows the results of visually observing the hue shift of the obtained recorded image. 2) Using the sublimation type thermal transfer member of Example 10 and the above-mentioned image receiving sheet, a speed difference mode method (feeding speed of image receiving sheet = 8.
4 mm / sec, feed speed of sublimation type thermal transfer member = 1.2 m
(m / sec), printing of a pattern image having 11 tones from low density to high density was repeated seven times. Also,
Using the sublimation-type thermal transfer members of Examples 11 and 12 and Comparative Example 6, the same printing was performed. Table 7 shows the results of visually observing the hue shift of the obtained recorded image.

[0113]

[Table 7]

As is clear from Table 7, when the sublimation type thermal transfer member of the embodiment is used, the hue is always constant irrespective of the number of printings, and the hue is constant over the entire density range of the image. A recorded image can be obtained. Furthermore, as a result of printing characters using the sublimation type thermal transfer body of Example 12 and Comparative Example 6, when using the sublimation type thermal transfer body of Example 12, good black characters were printed, When the sublimation-type thermal transfer recording medium of Comparative Example 6 was used, a character in which the horizontal line portion of the character was magenta was printed.

[00115]

According to the sublimation type thermal transfer body of the present invention, a hue shift does not occur between the middle and low density portions and the high density portion, and a recorded image having a constant hue in the entire density range of the image is received on the image receiving sheet. Can be formed on. Further, according to the sublimation-type thermal transfer body of the present invention, the density of the recorded image does not decrease even when it is repeatedly used many times, and the hue is always constant irrespective of the number of recordings, and the hue is constant over the entire density range. A certain recorded image can be formed on the image receiving sheet.

Continued on the front page (72) Inventor Yutaka Ariga 1-3-6 Nakamagome, Ota-ku, Tokyo Inside Ricoh Co., Ltd.

Claims (32)

[Claims] 1. A sublimation type thermal transfer member having a dye layer having a laminated structure containing two or more types of sublimation dyes having different hues on a support. Dn, D2, D3... Dn for each hue, the value of the hue showing the highest value (Dh) is 0 for the other hue. Sublimation type thermal transfer member characterized by being not less than 5 × Dh. 2. A sublimation-type thermal transfer material having a dye layer having a laminated structure containing two or more sublimable dyes having different hues on a support, and the mixing ratio of each sublimable dye belonging to the same hue in the dye layer. Dn, D2, D3... Dn for each hue, the value of the hue showing the highest value (Dh) is 0 for the other hue. A sublimation type thermal transfer member having a density of 7 × Dh or more. 3. The sublimation-type thermal transfer according to claim 1, wherein the sublimation dye in the hue to which the sublimation dye having the lowest solubility in toluene belongs is composed of at least two or more sublimation dyes of the same hue. body. 4. The sublimation-type thermal transfer member according to claim 3, wherein the solubility of the sublimable dye having the lowest solubility in toluene is less than 0.5 × Dh. 5. The sublimation type according to claim 3, wherein at least one sublimable dye other than the sublimable dye having the lowest solubility in toluene has a solubility in toluene of 0.5 × Dh or more. Thermal transfer body. 6. The sublimation-type thermal transfer member according to claim 3, wherein at least one sublimable dye other than the sublimable dye having the lowest solubility in toluene has a solubility in toluene of Dh or more. 7. The sublimation type thermal transfer according to claim 1, wherein the sublimation dye in the hue to which the sublimation dye having the highest solubility in toluene belongs comprises at least two or more sublimation dyes having the same hue. body. 8. The sublimation type thermal transfer member according to claim 7, wherein the solubility of the sublimable dye having the highest solubility in toluene is 2 × Dh or more. 9. The sublimation type according to claim 7, wherein at least one sublimable dye other than the sublimable dye having the highest solubility in toluene has a solubility in toluene of 0.5 × Dh or less. Thermal transfer body. 10. A sublimation type thermal transfer material having a dye layer having a laminated structure containing two or more kinds of sublimation dyes having different hues on a support, a mixing ratio of each sublimation dye belonging to the same hue in the dye layer. And the sum of the product of the solubility in toluene and the extinction coefficient is E1, E2, E3 · for each hue.
... A sublimation-type thermal transfer member characterized in that the value of each of the other hues is 0.5 × Eh or more with respect to the hue showing the highest value (Eh) when En. 11. A sublimation type thermal transfer material having a dye layer having a laminated structure containing two or more kinds of sublimation dyes having different hues on a support, the mixing ratio of each sublimation dye belonging to the same hue in the dye layer. And the sum of the product of the solubility in toluene and the extinction coefficient is E1, E2, E3 · for each hue.
... When En, the value in each of the other hues is 0.65 × Eh with respect to the hue showing the highest value (Eh).
A sublimation type thermal transfer member characterized by the above. 12. The sublimable dye in the hue to which the sublimable dye having the smallest product of the solubility in toluene and the extinction coefficient belongs to at least two or more sublimable dyes of the same hue. The sublimation-type thermal transfer member as described in the above. 13. The sublimation-type thermal transfer according to claim 12, wherein the product of the solubility and the extinction coefficient of the sublimable dye in toluene having the smallest product of the solubility in toluene and the extinction coefficient is less than 0.5 × Eh. body. 14. The product of the solubility of toluene and the extinction coefficient of at least one sublimable dye other than the sublimable dye having the smallest product of the solubility in toluene and the extinction coefficient is 0.
14. The sublimation-type thermal transfer member according to claim 12, wherein the thermal transfer member is at least 5 × Eh. 15. The product of the solubility of toluene and the extinction coefficient of at least one sublimable dye other than the sublimable dye having the smallest product of the solubility in toluene and the extinction coefficient is Eh.
14. The sublimation-type thermal transfer member according to claim 12, wherein: 16. The sublimable dye in the hue to which the sublimable dye having the largest product of the solubility in toluene and the extinction coefficient belongs is composed of at least two or more sublimable dyes of the same hue. The sublimation-type thermal transfer member as described in the above. 17. The sublimation-type thermal transfer member according to claim 16, wherein the product of the solubility of the sublimable dye having the largest product of the solubility in toluene and the extinction coefficient is 2 × Eh or more. 18. The product of the solubility and the extinction coefficient of at least one sublimable dye in toluene other than the sublimable dye having the largest product of the solubility and the extinction coefficient in toluene.
18. The sublimation-type thermal transfer member according to claim 16, wherein the thermal transfer member is not more than 5 × Eh. 19. In a sublimation type thermal transfer member having a dye layer having a laminated structure containing two or more kinds of sublimable dyes having different hues on a support, the kind of the sublimable dye in the upper layer of the laminated dye layer and the same. A sublimation-type thermal transfer member, wherein the compounding ratio is equal to the type of sublimable dye in the lower dye layer and the compounding ratio thereof. 20. A dye concentration and / or dye diffusion in a lower layer of a laminated dye layer in a sublimation type thermal transfer member having a dye layer having a laminated structure containing two or more sublimable dyes having different hues on a support. 20. The sublimation-type thermal transfer member according to claim 1, wherein the coefficient is larger than that of the upper layer. 21. In a sublimation-type thermal transfer member having a dye layer having a laminated structure containing two or more kinds of sublimable dyes having different hues on a support, the sublimable dye is in the form of particles in the lower layer of the laminated dye layer. 2. The method according to claim 1, wherein
21. The sublimation-type thermal transfer member according to any one of items 20 to 20. 22. The sublimation type thermal transfer body for multiple recording according to claim 20, wherein the lower layer is a dye supply layer and the upper layer is a dye transfer contributing layer and / or a low dyeing resin layer. 23. The sublimation type thermal transfer material for magenta color according to claim 1, wherein the sublimable dyes having different hues are a sublimable dye having a red hue and a sublimable dye having a violet hue. 24. The sublimation type thermal transfer for cyan color according to claim 1, wherein the sublimable dyes having different hues are a sublimable dye having a blue hue and a sublimable dye having a green hue. body. 25. The sublimable dye having a different hue is a sublimable dye having a yellow hue, a sublimable dye having a magenta hue, and a sublimable dye having a hue cyan. Sublimation type thermal transfer body for black. 26. A method for producing a sublimation-type thermal transfer member having a dye layer having a laminated structure containing two or more sublimable dyes having different hues on a support, wherein a solvent for an upper layer coating liquid laminated on the lower layer is used as a solvent. A method for producing a sublimation-type thermal transfer member, wherein a solvent having the same solubility of each sublimable dye contained in the lower layer is used. 27. A method for producing a sublimation-type thermal transfer member having a dye layer having a laminated structure containing two or more sublimable dyes having different hues on a support, as a solvent for an upper layer coating liquid to be laminated on a lower layer. A method for producing a sublimation-type thermal transfer member, wherein a solvent having a solubility of each sublimable dye contained in the lower layer of 20 g / l or less is used. 28. A method for producing a sublimation-type thermal transfer member having a dye layer having a laminated structure containing two or more sublimable dyes having different hues on a support, wherein a solvent for an upper layer coating liquid to be laminated on the lower layer is used as a solvent. A method for producing a sublimation-type thermal transfer member, comprising using a solvent containing an alcohol-based solvent as a main component. 29. A method for producing a sublimation type thermal transfer member having a dye layer having a laminated structure containing two or more kinds of sublimable dyes having different hues on a support, wherein a coating liquid containing all of the sublimable dyes is used. The method according to claim 26, wherein after coating on the support and drying to form a lower layer, a coating liquid containing no sublimable dye is applied to the lower layer and dried to form an upper layer.
29. The method for producing a sublimation-type thermal transfer member according to Item 28. 30. A method for producing a sublimation-type thermal transfer member having a dye layer having a laminated structure containing two or more sublimable dyes having different hues on a support, wherein a coating liquid for an upper layer to be laminated on the lower layer is as follows. A method for producing a sublimation-type thermal transfer body, comprising using a coating liquid containing the sublimable dye in accordance with a difference in solubility of each sublimable dye contained in the lower layer in the solvent for the upper layer coating liquid. 31. A method for producing a sublimation-type thermal transfer member having a dye layer having a laminated structure containing two or more sublimable dyes having different hues on a support, wherein the upper layer coating liquid to be laminated on the lower layer is Sublimation having the same hue as the sublimable dye in the lower layer and higher solubility in the upper layer coating solution solvent than the sublimable dye in accordance with the difference in the solubility of each sublimable dye contained in the lower layer in the upper layer coating solution solvent A method for producing a sublimation-type thermal transfer member, comprising using a coating solution containing a coloring dye. 32. A method of forming a recording image on an image receiving sheet using the sublimation type thermal transfer member according to claim 1 and setting the relative speed of the sublimation type thermal transfer member to the image receiving sheet to 1 / n (n> 1). Characteristic multiple recording method.