JP2986187B2 - Image forming method using thermal transfer material - Google Patents

Description

The present invention relates to an image forming method using a thermal transfer material,
More specifically, the present invention relates to an image forming method using a heat-sensitive transfer material characterized in that a specific compound is used as an image receiving substance.

[Conventional technology]

Conventionally, as a method of forming a color hard copy,
Color recording techniques such as an ink jet method, an electrophotographic method and a thermal transfer method are known.

In particular, the thermal transfer method has advantages such as easy operation and maintenance, reduction in size and cost of the apparatus, and low running cost.

However, in the thermal transfer method, a sheet-like thermal transfer material in which a fusible ink layer is provided on a support, that is, a transfer sheet is heated by a thermal head, and this ink is used as a sheet-like image receiving material, that is, a transfer sheet. A heat transfer material in the form of a sheet, in which an ink layer containing a heat-diffusible dye (sublimable dye) is provided on a support, that is, a transfer sheet, is heated by a heat-sensitive head. There is a thermal diffusion transfer method (sublimation transfer method) in which a coloring matter is transferred onto a sheet-like image receiving material, that is, a transfer receiving sheet.

However, the above thermal diffusion transfer method can control the gradation of an image by changing the transfer amount of the dye in accordance with the change in the thermal energy of the thermal head,
It can be preferably applied to the formation of a full-color image.

[Problems to be solved by the invention]

However, in the thermal diffusion transfer method, there is a problem that an image is easily re-transferred from a transfer-receiving sheet because a dye used in a thermal transfer material is a thermal diffusion material.

In order to prevent retransfer of an image, a technique of laminating an image on a sheet to be transferred has also been proposed. However, since the laminating means requires a post-process of lamination, there is a problem that the process becomes complicated.

Further, there has been proposed a technique for fixing a dye image by adding a compound to an image receiving layer of a transfer-receiving sheet and reacting the compound with a dye on the transfer sheet (JP-A-59-59495, No. 59-64393, No. 60-260391, No. 60
-110494).

According to these techniques, post-processing of laminating the image on the transfer sheet is not required, but the reactivity between the compound added in the image receiving layer and the dye on the transfer sheet is still low, and as a result, There is a problem that bleeding easily occurs in an image, and sufficient fixability cannot be obtained.

Therefore, an object of the present invention is to provide an image forming method using a heat-sensitive transfer material which can form an image having excellent fixability by including an image-receiving substance having high reactivity with a heat-diffusing dye in an image-receiving layer. Is to do.

[Means for solving the problem]

The inventors of the present invention have conducted intensive studies to achieve the above object, and as a result, as an image receiving substance to be contained in an image receiving layer, a compound represented by the following general formula (1), a polymer of the compound or a copolymer of the compound is particularly preferred. It has been found that by selecting a polymer, the reactivity of the ink layer of the thermal transfer material with the heat-diffusible dye can be increased to form an image having excellent fixability without bleeding or retransfer. It has been completed.

Therefore, the image forming method using the heat-sensitive transfer material of the present invention heats a heat-sensitive transfer material formed by providing an ink layer containing a heat-diffusible dye on a support in accordance with image information. The image is transferred to an image receiving material provided with an image receiving layer containing a compound represented by the following general formula (1) or a polymer or copolymer of the compound, and all or a part of the heat-diffusible dye and the following general formula An image is formed by a reaction product of the compound represented by (1) or a polymer or copolymer of the compound.

General formula (1) Wherein X is a halogen atom or an X′-R group (X ′
Represents a sulfur atom, a sulfonyl group, an oxygen atom or a quaternary nitrogen atom; R represents a hydrogen atom or a substituent;
Is a quaternary nitrogen atom, R is a substituent and X ′
And an atomic group that forms a ring with the group. ), And Y represents an atomic group necessary for forming a nitrogen-containing heterocyclic ring together with -C = N-. That is, in the present invention, as the substance contained in the image receiving layer of the image receiving material, the compound represented by the above general formula (1) having high reactivity with the heat diffusible dye in the ink layer of the thermal transfer material or the compound of the compound is used. By selecting a polymer or a copolymer, bleeding or retransfer of an image is effectively prevented, and the fixing property of the image is remarkably improved.

 Hereinafter, the configuration of the present invention will be specifically described.

In the compound represented by the general formula (1), X which is a leaving group represents a halogen atom such as a fluorine atom, a chlorine atom and a bromine atom, or an X′-R group described in detail below.

In the X'-R group, X 'represents a sulfur atom, a sulfonyl group, an oxygen atom, or a quaternary nitrogen atom, and R represents a hydrogen atom or a substituent. When X 'is a quaternary nitrogen atom, R may be an atomic group forming a ring together with X'.

Examples of the X'-R group include those represented by the following general formulas (1) to (4).

Formula -SO ₂ R ₁₀ R ₁₀ represents an OH group, an alkyl group, an aryl group. The alkyl group and the aryl group may be further substituted with an OH group, a carboxyl group, an alkyl group, a sulfonyl group, or the like.

General formula R ₁₁ and R ₁₂ each represent a hydrogen atom, an optionally substituted alkyl group, an arylamino group, or an amino group, and may form a ring together.

General formula R ₁₃ and R ₁₄ are each an optionally substituted alkyl group,
Represents an aryl group.

Formula -SR ₁₅ R ₁₅ is a hydrogen atom, a sulfoxyl group, an alkyl group optionally substituted with a halogen atom; a nitro group, a sulfoxyl group, an aryl group optionally substituted with a cyano group;
Represents a heterocyclic ring such as benzothiazole, benzoxazole, benzimidazole, imidazole, triazole, phenyltetrazole and the like which may be substituted by an alkyl group, an acylamino group, a hydroxyl group, a carboxyl group, a sulfoxyl group or the like.

The general formula -OR ₁₆ R ₁₆ represents a halogenated alkyl group; an aryl group which may be substituted with a nitro group, a sulfoxyl group, a cyano group, an alkyl group, or the like.

General formula R ₁₇ , R ₁₈ , and R ₁₉ each represent an optionally substituted alkyl group, aryl group, or amino group, and may form a ring together.

Specific examples of the above X'-R groups include the following.

In the compound represented by the general formula (1), the nitrogen-containing heterocyclic ring is preferably a 5- to 6-membered heterocyclic ring, and the number of nitrogen atoms on the heterocyclic ring is preferably 1 to 3, particularly 2 or 3
Are preferred. Further, it may contain a sulfur atom.

Further, in the general formula (1), the heterocyclic ring formed by Y includes a heterocyclic ring formed by condensing with another ring such as a benzene ring. Further, the heterocyclic ring includes those having a substituent on the ring. Examples of the substituent include a chlorine atom, a halogen atom such as a fluorine atom, an alkyl group, an amino group, a hydroxy group, an alkoxy group, an aryloxy group. , An alkylamino group, an arylamino group, an acylamino group, a sulfonyl group, a carbamoyl group, a sulfamoyl group, a heterocyclic group and the like, and those having a substituent are also included.

As these substituents, a group capable of improving the affinity for the image receiving layer, or increasing the immobility of the heat diffusible dye at the time of image formation and / or after image formation, and further preventing precipitation, It is preferably a group substituted with a group of

Examples of such a group include groups generally known as ballast groups in compounds (for example, couplers) used in conventional photographic light-sensitive materials. As the ballast group, a group having 6 to 30 carbon atoms is preferable.

Furthermore, examples of the above groups include polymer residues. When the compound has a polymer residue as one of the substituents, the polymer or copolymer of the compound represented by the general formula (1) may be a polymer or a copolymer represented by the following general formula (2). It is preferably a polymer or a copolymer having a derived repeating unit.

General formula (2) In the general formula (2), X and Y are the same as X and Y in the general formula (1), respectively. R ₁ and R ₂ each represent a divalent hydrocarbon group, J ₁ and J ₂ each represent a divalent bonding group, R ₃ represents an alkyl group or a hydrogen atom, n ₁ , n ₂ , m ₁ and m ₂ each represent 0 or 1.

Examples of the divalent hydrocarbon group represented by R ₁ and R ₂ include an alkylene group such as a methylene group, an ethylene group and a propylene group; an arylene group such as a phenylene group; a group obtained by combining the above groups such as a methylene phenylene group; And the like.

As the divalent linking group represented by J ₁ and J ₂ , -NHCO-,
-CONH-, -COO-, -OCO-, -SCO-, -COS-, -O
-, - S -, - SO -, - SO 2 -, - NH -, - CO- , and the like.

Further, in the polymer or copolymer of the compound represented by the general formula (1), a homopolymer derived from only the monomer represented by the general formula (2) may be used, A copolymer which is a copolymer with one or more other monomers may be used. Examples of a monomer (monomer) for forming such a copolymer include acrylates such as ethyl acrylate, butyl acrylate, and ethylhexyl acrylate; methacrylates such as methyl methacrylate, propyl methacrylate, and amyl methacrylate; styrene , Methylstyrene, p-
Styrenes such as sulfostyrene; acrylamides such as acrylamide, methylacrylamide and butylacrylamide; methacrylamides such as methacrylamide, methyl methacrylamide and ethyl methacrylamide;
And the like.

Specific examples of the compound represented by the general formula (1) include compounds represented by the following general formulas (A) to (G).

In the general formulas (A) to (G), X ₁ , X ₂ X ₃ are the same as X in the general formula (1), and R ₄ and R ₅ are:
Each represents a monovalent organic group. As the monovalent organic group, the group described as a substituent which may be contained in the nitrogen-containing heterocyclic ring in the compound represented by the general formula (1),
Ballast groups, polymer residues and the like.

Representative specific examples of the compound represented by the general formula (1) include those listed in Table 1 below, but the present invention is not limited thereto.

Further, the polymer or copolymer of the compound represented by the general formula (1) is a polymer or copolymer having a repeating unit derived from the monomer represented by the general formula (2). However, as the monomer represented by the general formula (2), those listed in Table 2 below can be mentioned as typical specific examples.

As the copolymer of the compound represented by the general formula (1), those listed in Table 3 below can be mentioned as typical specific examples.

The methods for synthesizing the copolymers listed in Table 3 above include:
The methods described in JP-A-63-144350 and JP-A-2-864 can be employed.

The compound represented by the general formula (1) is contained in the image receiving layer of the image receiving material, and the content thereof is preferably 0.1 to ²⁰ g, more preferably 0.3 to 10 g, per 1 m ² of the support in the image receiving material.

As a method for adding the compound represented by the general formula (1), the compound is dissolved or dispersed in a solvent such as ethanol, methanol, methyl ethyl ketone, toluene, methylene chloride, tetrahydrofuran, or water together with the resin constituting the image receiving layer. Thereafter, a method of coating the support on an image receiving material to add it to the image receiving layer is generally used.

As the support of the image receiving material, paper, coated paper, synthetic paper,
Examples include a white polyethylene terephthalate base film, a transparent polyethylene terephthalate base film, and RC paper.

Examples of the binder for the image receiving layer include polyester resins, polyvinyl chloride resins, copolymer resins of vinyl chloride and other monomers such as vinyl acetate, acrylates, polyvinylpyrrolidone, and polycarbonate resins.

If necessary, a release agent such as silicone oil or an image stabilizer such as an antioxidant or a UV absorber may be added to the surface of the image receiving layer.

In the present invention, the thermal diffusible dye contained in the ink layer of the thermal transfer material may be any of a yellow dye, a magenta dye, and a cyan dye when a monochromatic image is formed. Further, depending on the color tone of the image, any two or three of the three dyes may be used in combination.

Further, this ink layer is such that a yellow ink layer containing a binder and a yellow dye, a magenta ink layer containing a binder and a magenta dye, and a cyan ink layer containing a binder and a cyan dye are fixed along a plane direction. Is preferably formed on the support by repeating the above.

Further, in addition to the three ink layers arranged along the surface direction, a black ink layer containing a black image forming substance may be interposed between any two horizontally adjacent layers.

Examples of the cyan dye include JP-A-59-78896 and JP-A-59-78896.
-22798, 60-24996, 60-53563, 60-130
No. 735, No. 60-131292, No. 60-239289, No. 61-19396
No. 61-22993, No. 61-31292, No. 61-31467,
No. 61-35994, No. 61-49893, No. 61-148269, No. 62
-191191, 63-91288, 63-91287, 63-29
Examples thereof include naphthoquinone dyes, anthraquinone dyes, and azomethine dyes described in each publication such as No. 0793.

Examples of the magenta dye include JP-A-59-78896 and JP-A-59-78896.
No. 0-30392, No. 60-30394, No. 60-253595, No. 61-2
No. 62190, No. 63-5992, No. 63-205288, No. 64-159
And anthraquinone dyes, azo dyes, and azomethine dyes described in JP-A-64-63194 and the like.

As the yellow dye, JP-A-59-78896, 6
0-27594, 60-31560, 60-53565, 61-12
Examples thereof include methine dyes, azo dyes, quinophthalone dyes and anthrisothiazole dyes described in JP-A Nos. 394 and 63-122594.

Particularly preferred thermal diffusible dyes are azomethine obtained by a coupling reaction between a compound having a closed or closed active methylene group and an oxidized p-phenylenediamine derivative or an oxidized p-aminophenol derivative. An oxidized form of a dye, a phenol or naphthol derivative and a p-phenylenediamine derivative or p-
An indoaniline dye obtained by a coupling reaction with an oxidized form of an aminophenol derivative.

Further, these heat diffusible dyes preferably have an amino group or a hydroxyl group as a substituent of a portion other than the auxiliary chromophore.

The amount of the heat diffusing dye used is 1 m ² of the support of the thermal transfer material.
It is preferably 0.1 to 20 g, particularly preferably 0.2 to 5 g.

Examples of the binder for the ink layer include water-soluble polymers such as cellulose, polyacrylic acid, polyvinyl alcohol, and polyvinylpyrrolidone, and organic solvents such as acrylic resin, methacrylic resin, polystyrene, polycarbonate, polyether sulfone, ethyl cellulose, and nitrocellulose. And a polymer soluble in water.

When a polymer soluble in an organic solvent is used as a binder, the polymer may be dissolved in an organic solvent and used, or the polymer may be used in the form of a latex dispersion in the organic solvent.

The amount of binder used is 1m
Per ^2, 0.1 to 50 g is preferred, particularly 0.5~10g is preferred.

The ink layer can be formed as follows.
First, the constituent materials of the ink layer are dissolved in a solvent or dispersed in fine particles to prepare an ink, and the ink is applied on a support or printed on the support by a gravure printing method or the like. To form an ink layer.

The thickness of the ink layer, that is, the heat-sensitive layer, is 0.1 to
A range of 5 μm is preferred.

The support of the heat-sensitive transfer material or the image-receiving material must have good dimensional stability and be able to withstand the heat at the time of recording with a heat-sensitive head. Heat-resistant plastic films such as thin paper, polyethylene terephthalate, polyamide, and polycarbonate can be used.

The thickness of the support is preferably 2 to 10 μm. Further, the support may be provided with an undercoat layer for the purpose of improving the adhesiveness to the binder and preventing transfer and dyeing of the heat diffusible dye to the support side.

Further, a slipping layer may be provided on the back surface of the support opposite to the ink layer for the purpose of preventing the head from sticking to the support.

As a solvent for adjusting the ink of the ink layer,
Water; alcohols such as ethanol and propanol; esters such as ethyl acetate; aromatics such as toluene, xylene and chlorobenzene; ketones such as acetone and methyl ethyl ketone; ethers such as tetrahydrofuran and dioxane; chloroform; Chlorine-based solvents such as ethylene;

The heat-sensitive transfer material is basically constituted by providing an ink layer composed of a heat-diffusible dye and a binder on a support, and described in JP-A-59-106997 on this ink layer. A heat-fusible layer containing such a heat-fusible compound may be provided.

In the image forming method using the heat-sensitive transfer material of the present invention, a heat-sensitive transfer material formed by providing an ink layer containing a heat-diffusible dye on a support according to image information is heated, The image is transferred to an image receiving material provided with an image receiving layer containing the compound represented by the general formula (1) or a polymer or a copolymer of the compound, and all or a part of the heat-diffusible dye and the general formula ( An image is formed with the compound represented by 1) or a reaction product with the polymer or copolymer of the compound.

Specifically, the ink layer surface of the thermal transfer material and the image receiving layer surface of the image receiving material are overlapped, and in this state, from either the surface of the thermal transfer material or the image receiving material, preferably from the surface of the thermal transfer material, for example, Heating is performed according to image information using a heating means such as a thermal head. By this heating, the ink in the ink layer of the thermal transfer material has relatively low energy, and is easily transferred and transferred to the image receiving layer of the image receiving material according to the magnitude of the heating energy.

When the ink in the ink layer is transferred to the image receiving layer in this manner, the transferred ink is combined with the image receiving substance in the image receiving layer, that is, the compound represented by the general formula (1) or the polymer or copolymer of the compound. The reactants react with each other, and the reactant forms an image.

〔Example〕

Hereinafter, examples of the present invention will be described together with comparative examples, but the present invention is not limited to these embodiments.

[Example 1] (Preparation of ink layer) 10 g of a yellow dye represented by the above structural formula and 24 g of a polyvinyl butyral resin (binder) were dissolved in 400 ml of methyl ethyl ketone to prepare a yellow ink 1.

This ink 1 was applied onto a 4.5 μm thick polyethylene terephthalate film (support) so that the amount of the adhered yellow dye was 1.0 g / m ² , thereby producing a thermal transfer material 1.

In addition, on the back surface of the polyethylene terephthalate film, a polyvinyl butyral (0.4 g / m ² ) containing polyvinyl stearate (0.25 g / m ² ) was used as an anti-sticking layer.
m ² ) layer is provided.

(Preparation of Image Receiving Material) An image receiving material 1 was prepared by coating polyvinyl chloride containing a compound (exemplified compound T-1) represented by the general formula (1) on one surface of a paper (support) laminated with polyethylene. Was prepared.

One surface of the laminated paper, that is, the surface on which the polyvinyl chloride was applied, was preliminarily containing a white pigment (titanium dioxide) and a bluing agent.

The coating amount of Exemplified Compound T-1 was 5 g / m ² , and the coating amount of polyvinyl chloride was 10 g / m ² .

The image receiving layer contained 0.15 g / m ^{2 of} silicone oil.

(Image Forming Method Using Thermal Transfer Material) The thermal transfer material 1 and the image receiving material 1 are overlapped so that the ink layer surface of the thermal transfer material 1 and the image receiving layer surface of the image receiving material 1 face each other. When a heat-sensitive transfer image was formed by contacting the back surface of Sample No. 1, a yellow heat-sensitive transfer image 1 having excellent gradation was obtained.

When the maximum density (Dmax) of this thermal transfer image 1 was measured, it was 1.88. Dmax was measured by PDA-65 (manufactured by Konica Corporation).

 The thermal transfer conditions are as follows.

Linear density of main scanning and sub-scanning; 8 dots / mm Recording power; 0.6 W / dot Heating time of thermal head: Heating time was adjusted stepwise from 20 msec to 0.2 msec.

(Evaluation) (1) Nijimi The thermal transfer image 1 described above was sandwiched between laminated pouch films, and these were laminated using a laminator LAC1702 “PRO” (manufactured by Fujipla Co., Ltd.).

Laminated thermal transfer image 1 under the condition of 77 ° C
After standing for 48 hours, the bleeding of the thermal transfer image 1 was visually evaluated.

The evaluation was “○” when no bleeding was observed, and “×” when bleeding was severe.

(2) Retransfer The separately formed thermal transfer image 1 was superimposed on the image receiving material 9 shown in Table 4 below, applied with a load of 20 kg / m ² and left at a temperature of 60 ° C. for 48 hours. The degree of retransfer of the image from the image 1 to the image receiving material 9 was visually evaluated.

The evaluation was "O" when retransfer was not observed, and "X" when retransfer occurred.

 The above results are shown in Table 4 below.

Examples 2 to 12 In Example 1, the type and content of the compound represented by the general formula (1) or the polymer or copolymer of the compound and the binder of the image receiving layer are shown in Table 4 below. Image receiving material 2 for the present invention in the same manner except that
~ 12 were prepared.

Using each of these image receiving materials 2 to 12 and the thermal transfer material 1 of Example 1, thermal transfer images 2 to 12 were formed in the same manner as in Example 1.

Dmax of these thermal transfer images 2 to 12 are as shown in Table 4.

Next, bleeding and retransfer were evaluated for the thermal transfer images 2 to 12 in the same manner as in Example 1. The results are as shown in Table 4.

[Comparative Examples 1 and 2] In Example 1, the compound represented by the general formula (1) was not used at all, and the binder of the image receiving layer was changed to the following fourth compound.
Image receiving materials a and b for comparison were prepared in the same manner except that they were as shown in the table.

Using each of these image receiving materials a and b and the thermal transfer material 1 of Example 1, thermal transfer images a 'and b' were formed in the same manner as in Example 1.

Dmax of these thermal transfer images a 'and b' are as shown in Table 4.

Next, bleeding and retransfer were evaluated for the thermal transfer images a 'and b' in the same manner as in Example 1. The results are as shown in Table 4.

As shown in Table 4 above, according to Examples 1 to 12 of the present invention, a thermal transfer image having a high image density and excellent fixability can be obtained.

On the other hand, in Comparative Examples 1 and 2, a comparative image receiving material containing no compound represented by the general formula (1) was used.
a, b, the obtained thermal transfer image a ′,
b 'is liable to cause bleeding and retransfer easily, and it is clear that the fixing property is inferior to those of the examples of the present invention.

Examples 13 and 14 Thermal transfer materials 2 and 3 were produced in the same manner as in Example 1 except that the yellow dye of the thermal transfer material 1 was changed to the following magenta dye and cyan dye, respectively.

Using each of the thermal transfer materials 2 and 3 and the image receiving material 1 of Example 1, the thermal transfer images 13 and 1 were produced in the same manner as in Example 1.
Formed four.

Dmax of these thermal transfer images 13 and 14 is 2.1
5, 2.08.

When the thermal transfer images 13 and 14 were evaluated for bleeding and retransfer in the same manner as in Example 1, bleeding and retransfer did not occur in both of the thermal transfer images 13 and 14.
It was confirmed that the fixability was good.

[Comparative Examples 3 and 4] Using each of the thermal transfer materials 2 and 3 obtained in Examples 13 and 14 and an image receiving material a for comparison, a thermal transfer image c ′, d 'formed.

Dmax of these thermal transfer images c 'and d' is 2.
13, 2.05.

When the thermal transfer images c 'and d' were evaluated for bleeding and retransfer in the same manner as in Example 1, bleeding and retransfer occurred in both of the thermal transfer images c 'and d'. It was confirmed that the fixing property was inferior to Examples 13 and 14 of the present invention.

Example 15 Example 1 was performed using the inks used in Examples 1, 13, and 14.
A yellow, magenta, and cyan ink layers were successively and repeatedly applied along the surface direction on the same support as in Example 1 to prepare a full-color thermal transfer material 4.

Using the thermal transfer material 4 and the image receiving material 2, a full-color thermal transfer image 15 was formed by a video printer (VY-100 manufactured by Hitachi, Ltd.).

The thermal transfer image 15 was evaluated for bleeding and retransfer in the same manner as in Example 1. As a result, no bleeding and retransfer were observed, and the fixability was good.

〔The invention's effect〕

As described above in detail, according to the present invention, as the image-receiving substance contained in the image-receiving layer of the image-receiving material, a specific substance having high reactivity with the heat-diffusible dye of the ink layer of the thermal transfer material, Since a compound represented by the formula (1) or a polymer or copolymer of the compound was selected,
It is possible to form a thermal transfer image having excellent fixability without causing bleeding or retransfer.

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-60-260391 (JP, A) JP-A-60-260381 (JP, A) JP-A-1-188391 (JP, A) (58) Field (Int.Cl. ⁶ , DB name) B41M 5/38-5/40

Claims (1)

(57) [Claims] A heat-sensitive transfer material comprising an ink layer containing a heat-diffusible dye provided on a support is heated in accordance with image information, and the heat-diffusible dye is represented by the following general formula (1). Transferred to an image receiving material provided with an image receiving layer containing a compound or a polymer or copolymer of the compound, and all or a part of the heat diffusible dye and a compound represented by the following general formula (1) or An image forming method using a heat-sensitive transfer material, wherein an image is formed by a reaction product of the compound with a polymer or copolymer. General formula (1) Wherein X is a halogen atom or an X′-R group (X ′
Represents a sulfur atom, a sulfonyl group, an oxygen atom or a quaternary nitrogen atom; R represents a hydrogen atom or a substituent;
Is a quaternary nitrogen atom, R is a substituent and X ′
And an atomic group that forms a ring with the group. ), And Y represents an atomic group necessary for forming a nitrogen-containing heterocyclic ring together with -C = N-. ]