JPH08108637A - Thermal transfer sheet - Google Patents

Abstract

PURPOSE: To provide a thermal transfer sheet excellent in gradation properties and forming a high density yellow color good in preservability. CONSTITUTION: A thermal transfer sheet is produced by coating a sheet like support such as a plastic film or paper with ink prepared by dissolving coloring matter represented by formula [I] (R1 is a hydrogen atom, a halogen atom, a nitro group, an alkyl group or an alkoxy group and R2 is a hydrogen atom, an alkyl group, an alkoxy group or an alkoxyalkyl group) in a medium along with a binder or dispersing the same in the medium in a fine granular form along with the binder and drying the coated support. As the binder, a water-soluble resin, for example, a cellulosic resin and one or more kind of a resin soluble in an org. solvent such as ethyl cellulose or water are used. As the medium, alcohols, cellosolves or aromatic hydrocarbons are used.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a heat-sensitive transfer sheet. More specifically, it relates to a heat-sensitive transfer sheet in which an ink layer containing a dye having excellent sublimation property is carried on a support.

[0002]

2. Description of the Related Art Electrophotography, ink jet, thermal transfer and the like have been proposed as color recording techniques. Of these, the thermal transfer recording method is considered to be advantageous because the maintenance and operability of the apparatus are easy. Conventionally, a yellow dye applied to thermal transfer recording has been selected and used from disperse dyes, oil-soluble dyes and the like. By the way, the dye used for the transfer sheet is easily sublimated by the heat of the thermal recording head and does not cause thermal decomposition, has a large molecular extinction coefficient, has good color reproducibility, light resistance, weather resistance and heat resistance. Various quality characteristics have been demanded such as superiority and safety and health problems. From the above viewpoints, some have been found to be satisfactory, but they have various drawbacks. In particular, with the development of color recording technology, high-definition image quality close to that of silver halide photography has been demanded. To meet this requirement, conventional ones have been unsatisfactory.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a thermal transfer sheet characterized in that an ink layer containing a yellow dye satisfying the above quality characteristics is carried on a support.

[0004]

Means for Solving the Problems The present invention has been accomplished as a result of intensive research to find a yellow dye that is suitable and clear for preparing a thermal transfer sheet. That is, the present invention
(1) The following general formula (1)

[0005]

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(Wherein R ₁ is a hydrogen atom, a halogen atom,
A nitro group, (C ₁ ~C ₆₎ alkyl, (C ₁ ~C ₆₎
Represents an alkoxy group, R ₂ is a hydrogen atom, an alkyl group,
Substituted or unsubstituted (C ₁ -C ₆ ) alkoxy (C ₁
To C ₆ ) alkyl group, aralkyl group, aryloxy (C
₁ -C ₆₎ alkyl group, cyano (C _{1 ~C 6)} alkyl group, substituted with a chlorine atom or a bromine atom (C ₁ ~
C ₆ ) alkyl group, substituted or unsubstituted phenyl group,
Naphthyl group, cycloalkyl group, cycloalkyl (C ₁
To C ₆ ) alkyl group, alkenyl group, araalkenyl group, (C ₁ -C ₆ ) alkyl group substituted with a heterocyclic group, (C ₁ -C ₆ ) alkoxy (C ₁ substituted with a heterocyclic group) ₁ -C ₆₎ alkyl group, an acyloxy (C _{1 ~C 6)}
Alkyl group, (C ₁ -C ₆ ) alkoxycarbonyloxy (C ₁ -C ₆ ) alkyl group, aryloxycarbonyloxy (C ₁ -C ₆ ) alkyl group, phenylcarbamoyloxy (C ₁ -C ₆ ) alkyl group , -Alkylene-N-
R ₃ R _4, -N-R ₃ R ₄ (wherein R ₃ and R ₄ each independently represent a hydrogen atom, (C ₁ ~C ₆₎ alkyl group, an acyl group, (C ₁ ~C ₆₎ alkoxycarbonyl A substituted or unsubstituted phenoxycarbonyl group, (C ₁ -C
₆ ) represents an alkylsulfonyl group, an arylsulfonyl group or R ₃ and R ₄ together with the nitrogen atom form a 5- or 6-membered heterocycle. However, the case where both R ₃ and R ₄ are hydrogen atoms is excluded. ) Is represented. The present invention provides a heat-sensitive transfer sheet, which comprises an ink layer containing a monoazo compound represented by the above (4) supported on a support.

Examples of the halogen atom represented by R ₁ in the general formula (1) include a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the like. Examples of the (C ₁ -C ₆ ) alkyl group include a methyl group, an ethyl group, a propyl group,
Examples thereof include a butyl group, a pentyl group and a hexyl group.
Examples of the (C ₁ -C ₆ ) alkoxy group include a methoxy group, an ethoxy group, a propoxy group, a butoxy group, a pentoxy group and a hexoxy group.

Specific examples of R ₂ in the general formula (1) include C ₁ -C ₆ linear or branched alkyl groups, alkoxyalkyl groups, alkoxyalkoxyalkyl groups, alkoxyalkoxyalkoxyalkyl groups,
Substitution of an alkoxyalkoxyalkoxyalkoxyalkyl group, an aryloxyalkyl group, an aryloxyalkoxyalkyl group, an aryloxyalkoxyalkoxyalkyl group, an aralkoxyalkyl group, an aralkoxyalkoxyalkyl group, an aralkoxyalkoxyalkoxyalkyl group, or the like. Unsubstituted alkoxyalkyl group, aryloxyalkyl group, cyanoalkyl group, chloroalkyl group, bromoalkyl group, phenyl group, naphthyl group, cycloalkyl group, cycloalkylalkyl group, cycloalkylalkoxyalkyl group, cycloalkoxyalkyl group, Cycloalkoxyalkoxyalkyl group, alkenyl group, araalkenyl group, tetrafurfurylalkyl group, tetrafurfurylalkoxyalkyl group, acyloxyalkoxy Group, alkoxycarbonyloxy group, an aryloxycarbonyl oxyalkyl group, phenyl carbamoylonium alkoxyalkyl group, a substituted or unsubstituted amino group, and a substituted or unsubstituted aminoalkyl groups and the like. Here, alkyl and alkoxy are, for example, C _{1 to} C ₆ , specifically, methyl,
Ethyl, propyl, butyl, pentyl, hexyl, methoxy, ethoxy, propoxy, butoxy, pentoxy,
Hexoxy and the like can be mentioned.

The compound represented by the general formula (1) is represented by the general formula (2)

[0010]

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(In the formula, R ₁ has the same meaning as described above.)
The diazotized amine represented by the general formula (3)

[0012]

[Chemical 4]

(In the formula, R ₂ has the same meaning as described above.)
It can be obtained by coupling with an aniline derivative represented by Examples of the diazo component of the general formula (2) include O-amino-benzoic acid-tetrahydrofurfuryl ester, m-amino-benzoic acid-tetrahydrofurfuryl ester, p-amino-benzoic acid-tetrahydrofurfuryl ester, 3- Amino-4-nitro-
Benzoic acid-tetrahydrofurfuryl ester, 3-amino-6-nitro-benzoic acid-tetrahydrofurfuryl ester, 2-amino-6-nitro-benzoic acid-tetrahydrofurfuryl ester, 2-amino-4-nitro-benzoic acid -Tetrahydrofurfuryl ester, 3-amino-4-chloro-benzoic acid-tetrahydrofurfuryl ester, 3-amino-6-chloro-benzoic acid-tetrahydrofurfuryl ester, 2-amino-5-chloro-benzoic acid-tetrahydro Furfuryl ester, 3-amino-
4-Brom-benzoic acid-tetrahydrofurfuryl ester, 2-amino-5-bromo-benzoic acid tetrahydrofurfuryl ester, 3-amino-4-methyl-benzoic acid-tetrahydrofurfuryl ester, 3-amino-4-
Methyl-benzoic acid-tetrahydrofurfuryl ester 3
-Amino-4-methoxy-benzoic acid-tetrahydrofurfuryl ester and the like can be mentioned.

On the other hand, examples of the coupler component of the general formula (3) include 3-cyano-4-methyl-6-hydro-2.
-Pyridone, N-methyl-3-cyano-4-methyl-6
-Hydro-2-pyridone, N-ethyl-3-cyano-4
-Methyl-6-hydro-2-pyridone, N- (n-butyl) -3-cyano-4-methyl-6-hydro-2-pyridone, N-isobutyl-3-cyano-4-methyl-6-
Hydro-2-pyridone, N-ethoxypropyl-3-cyano-4-methyl-6-hydro-2-pyridone, N-methoxyethoxypropyl-3-cyano-4-methyl-6
-Hydro-2-pyridone, N-methoxyethoxyethoxypropyl-3-cyano-4-methyl-6-hydro-2
-Pyridone, N-methoxyethoxyethoxyethoxypropyl-3-cyano-4-methyl-6-hydro-2-pyridone, N-benzyl-3-cyano-4-methyl-6-
Hydro-2-pyridone, N- (p-methylbenzyl)-
3-cyano-4-methyl-6-hydro-2-pyridone,
N-phenoxypropyl-3-cyano-4-methyl-6
-Hydro-2-pyridone, N-phenoxyethoxypropyl-3-cyano-4-methyl-6-hydro-2-pyridone, N-phenoxyethoxyethoxypropyl-3-
Cyano-4-methyl-6-hydro-2-pyridone, N-
Phenylethoxypropyl-3-cyano-4-methyl-
6-hydro-2-pyridone, N-phenylethoxyethoxypropyl-3-cyano-4-methyl-6-hydro-
2-pyridone, N-phenylethoxyethoxyethoxypropyl-3-cyano-4-methyl-6-hydro-2-
Pyridone, N-cyanomethyl-3-cyano-4-methyl-6-hydro-2-pyridone, N-chloromethyl-3-
Cyano-4-methyl-6-hydro-2-pyridone, N-
Phenyl-3-cyano-4-methyl-6-hydro-2-
Pyridone, N- (p-methylphenyl) -3-cyano-
4-Methyl-6-hydro-2-pyridone, N-cyclohexylmethyl-3-cyano-4-methyl-6-hydro-
2-pyridone, N-cyclohexylethoxypropyl-
3-cyano-4-methyl-6-hydro-2-pyridone,
N-cyclohexyloxypropyl-3-cyano-4-
Methyl-6-hydro-2-pyridone, N-cyclohexyloxyethoxypropyl-3-cyano-4-methyl-
6-hydro-2-pyridone, N-allyl-3-cyano-
4-Methyl-6-hydro-2-pyridone, N-phenylallyl-3-cyano-4-methyl-6-hydro-2-pyridone, N-furfurylmethyl-3-cyano-4-methyl-6-hydro -2-pyridone, N-furfuryl methoxypropyl-3-cyano-4-methyl-6-hydro-2
-Pyridone, N-acetoxyethyl-3-cyano-4-
Methyl-6-hydro-2-pyridone, N-benzoyloxyethyl-3-cyano-4-methyl-6-hydro-2
-Pyridone, N-methoxycarbonyloxyethyl-3
-Cyano-4-methyl-6-hydro-2-pyridone, N
-Phenoxycarbonyloxyethyl-3-cyano-4
-Methyl-6-hydro-2-pyridone, N-phenylaminocarbonyloxyethyl-3-cyano-4-methyl-6-hydro-2-pyridone, N-diethylaminopropyl-3-cyano-4-methyl-6- Hydro-2-pyridone, N-phenylcarbonylaminoethyl-3-cyano-4-methyl-6-hydro-2-pyridone, N-ethoxycarbonylaminoethyl-3-cyano-4-methyl-6-hydro-2- Pyridone, N-phenoxycarbonylaminoethyl-3-cyano-4-methyl-6-hydro-2-pyridone, N- (n-propyloxyethoxycarbonylaminoethyl-3-cyano-4-methyl-6-
Hydro-2-pyridone, N-ethylsulfonylaminoethyl-3-cyano-4-methyl-6-hydro-2-pyridone, N-phenylsulfonylaminoethyl-3-cyano-4-methyl-6-hydro-2- Pyridone, N-morpholinopropyl-3-cyano-4-methyl-6-hydro-2-pyridone, N-piperazinylethyl-3-cyano-4-methyl-6-hydro-2-pyridone, N-pyrimidinylethyl -3-Cyano-4-methyl-6-hydro-
2-pyridone, N-dimethylamino-3-cyano-4-
Methyl-6-hydro-2-pyridone, N-ethylamino-3-cyano-4-methyl-6-hydro-2-pyridone, N-methoxypropyl-3-cyano-4-methyl-
6-hydro-2-pyridone, N-naphthoxypropyl-
Examples thereof include 3-cyano-4-methyl-6-hydro-2-pyridone.

For the heat-sensitive transfer sheet of the present invention, an ink is prepared in advance by dissolving the dye of the general formula (1) together with a binder in a medium or dispersing it in the form of fine particles, and the ink is prepared from a plastic film or paper. It is manufactured by coating on a sheet-shaped support and drying.

Examples of the binder for preparing the ink include water-soluble resins such as cellulose-based, acrylic acid-based and starch-based resins, acrylic resins, methacrylic resins, polystyrene resins, polycarbonate resins, polysulfone resins, polyester resins and polyethers. One type or two or more types of resins soluble in an organic solvent such as a sulfone resin or ethyl cellulose or in water are used.

Water as a medium for ink preparation; alcohols such as methanol, ethanol and butanol;
Cellosolves such as methyl cellosolve and ethyl cellosolve; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; toluene,
Aromatic hydrocarbons such as xylene and chlorobenzene; Chlorine solvents such as methylene chloride, chloroform, dichloroethane and trichloroethane; Acetic acid esters such as ethyl acetate and butyl acetate; Ethers such as tetrahydrofuran and dioxane; N, N -Dimethylformamide,
Organic solvents such as N-methylpyrrolidone and dimethylimidazolidinone are used alone or as a mixture of two or more.

As the support to which the ink is applied for producing the heat-sensitive transfer sheet, condenser paper, cellophane, or a plastic film having good heat resistance such as polyester, polyamide, polyimide or polyether sulfone is used. The ink can be applied on the support by using a bar coater, a roll coater, a knife coater, a gravure printing machine or the like. The thickness of this support is preferably about 3 to 50 μm. The thickness of the ink coating layer after drying is 0.1 to 10 μm, preferably 0.4 to
Apply so as to have a thickness of 5.0 μm. Next, the ratio of the pigment to the binder and the medium in the ink is usually 0.5 pigment.
~ 15 wt%, binder 3-15 wt%, medium 70-9
6.5%, preferably 1 to 10% by weight of dye, 4 to binder
12% by weight and medium 78 to 95% by weight. However, this ratio does not restrict the present invention.

As the receiving sheet, paper coated with polyester resin or polyamide resin, synthetic paper such as polypropylene, polyvinyl chloride or polyester, and transparent sheets of synthetic resin such as polyester are usually used as the receiving sheet. Those known per se can be used as they are. The transfer of the dye to the receiving sheet may be performed by a recording device such as a thermal printer (for example, thermal printer TN-5400 manufactured by Toshiba Corp.) in about 1 to 30 ms.

[0020]

The present invention will be described in more detail by way of examples. In the examples, "parts" and "%" are parts by weight and% by weight, respectively. Example 1 1) Method of preparing ink The following formula (4)

[0021]

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4 parts of the dye compound of 6 and ethyl cellulose 6
Part, 45 parts of toluene, and 45 parts of methyl ethyl ketone were treated with a ball mill for 3 hours to prepare an ink. 2) Method for producing transfer sheet Using a bar coater, the above ink composition was applied to a polyethylene terephthalate (PET) film to give a dry film thickness of 6 μm.
To obtain a transfer sheet. No dye deposition was observed on the dried ink layer. 3) Preparation method of receiving sheet The receiving sheet is 15 parts of polyester resin (Nippon Gosei Co., Ltd., product name: TP-220), amino-modified silicone (Shin-Etsu Chemical Co., Ltd., product name: KF393) 0.5.
Part, methyl ethyl ketone 20 parts, and xylene 10 parts were applied to a 150 μm synthetic paper (manufactured by Oji Yuka Co., Ltd., product name: FPG-150) to a dry film thickness of about 5 μm, and 100 ° C. for 30 minutes. Curing was performed to prepare a receiving sheet. 4) Transfer recording The ink coated surface of the transfer sheet was superposed on the receiving sheet and recording was performed under the following conditions using a thermal head to obtain a recording with a clear yellow color and a color density of 1.31. Recording conditions Linear density in main scanning and sub-scanning: 8 dodd / mm Recording power: 0.25 W / dod Head heating time: 15 msec Color density was measured using a densitometer RD-914 (manufactured by Macbeth, USA).

Examples 2 to 58 Inks were prepared in the same manner as in Example 1 using 4.0 parts of the dyes shown in Table 1, and then transfer sheets were prepared.
Transfer recording was performed in the same manner as in Example 1 using these transfer sheets. Then, recordings each having a high color density of yellow shown in Table 1 were obtained.

[0024]

[Table 1] Table 1 Example -COOCH2Tf R ₁ R ₂ Color density Substitution position 2 4 H -H 1.29 3 4 H -CH3 1.31 4 4 H -C4H9 (iso) 1.31 5 4 H-(n) C3H6OC2H5 1.26 6 4 H- (n) C3H6OC2H4OCH3 1.24 7 4 H- (n) C3H6OC2H4OC2H4OCH3 1.23 8 4 H- (n) C3H6OC2H4OC2H4OC2H4OCH3 1.21 9 4 H-CH2P1CH4H1CH4P12CH1P4H1CH4P1CH4H1CH4P1CH4H1CH4P1CH4H1CH4P1CH4H1CH4P1CH4H1CH4P1CH4H1CH4P1CH4H2CH4P1CH4H1CH4P1CH4H1CH4P1CH4H1CH4P1CH4H1CH4P1CH4H1CH4P1CH4H1CH4P1CH4H1CH4P1CH4H1CH4P1CH4H1CH4H1CH4P1CH4H1CH4H1CH4H1CH4H1CH4H1CH4H1CH4H1CH4H1CH4H1CH4H1CH4H1CH4H1CH4H1CH4PCH2PCH2PCH2CH2PH1.21 4 H-(n) C3H6OPh 1.20 13 4 H-(n) C3H6OC2H4OPh 1.19 14 4 H-(n) C3H6OC2H4OC2H4OPh 1.18 15 4 H-(n) C3H6OC2H4Ph1.21 16 4 H-(n) C4H2H4OC4H4OC2H4OP2 1. ) C3H6OC2H4OC2H4OC2H4Ph 1.19 18 4 H -CH2CN 1.25 19 4 H -CH2Cl 1.24 20 4 H -Ph 1.24 21 4 H -PhCH3 (p) 1.23 22 4 H -Ch 1.24 23 4 H -CH2Ch 1.23 24C4H 6-H 1.29 25 4 H-(n) C3H6OCh 1.21 26 4 H-(n) C3H6OC2H4OCh 1.20 27 4 H -CH2CH = CH2 1.27 28 4 H -CH2CH = CHPh 1.23 29 4 H -CH2Fu 1.25 30 4 H-(n) C3H6OCH 2Fu 1.21 31 4 H -C2H4OCOCH3 1.24 32 4 H -C2H4OCOPh 1.19 33 4 H -C2H4OCOOCH3 1.24 34 4 H -C2H4OCOOPh 1.21 35 4 H -C2H4C4H4 (4) C4H-(n) C2H4 (N4C2H4) 1.22 38 4 H -C2H4NHCOOC2H5 1.24 39 4 H -C2H4NHCOOPh 1.23 40 4 H -C2H4NHCOOC2H4OC4H9 (n) 1.21 41 4 H -C2H4NHSO2C2H5 1.27 442 H -C2H4H4NH4H4NH4H4NH4H4NH4H4NHSO2P4 1.45 4 H -C2H4Py 1.20 46 4 H -N (CH3) 2 1.25 47 4 H -NHC2H5 1.25 48 4 2-NO2-(n) C3H6OCH3 1.19 49 4 2-Cl-(n) C3H6OCH3 1.20 50 2 4-NO2-( n) C3H6OCH3 1.19 51 2 4-Br-(n) C3H6OCH3 1.18 52 3 6-CH3-(n) C3H6OCH3 1.28 53 3 6-OCH _3- (n) C3H6OCH3 1.26 54 3 6-Cl-(n) C3H6OCH3 1.19 55 2 4-NO2-(n) C3H6OCH3 1.20 56 4 3-NO2-(n) C3H6OCH3 1.21 57 4 2-NO2 -C2H5 1.20 58 4 H-(n) C3H6ONh (2) 1.20 Note) Tf: Tetrahydrofurfuryl group Ph : F Alkylsulfonyl group Ch: cyclohexyl Fu: furfuryl group Mo: morpholino Pi: piperazinyl group Py: pyrimidyl Nh: naphthyl group

[0025]

When thermal transfer recording is carried out with the heat-sensitive transfer sheet of the present invention, a yellow image having excellent gradation and high color density can be obtained. Further, since the color reproducibility is good and the light resistance, weather resistance and heat resistance are excellent, it is possible to record an image with high storage stability.

Claims (1)

[Claims] 1. A general formula (1): (In the formula, R ₁ is a hydrogen atom, a halogen atom, a nitro group,
Represents a (C ₁ -C ₆ ) alkyl group or a (C ₁ -C ₆ ) alkoxy group, and R ₂ represents a hydrogen atom, an alkyl group, or a substituted or unsubstituted (C ₁ -C ₆ ) alkoxy (C ₁ -C _6). ) Alkyl group, aralkyl group, aryloxy (C ₁ -C ₆ ).
Alkyl group, cyano (C ₁ ~C ₆₎ alkyl group, substituted with a chlorine atom or a bromine atom (C ₁ ~C ₆₎ alkyl group, a substituted or unsubstituted phenyl group, a naphthyl group, a cycloalkyl group, a cycloalkyl (C ₁ -C ₆ ) alkyl group, alkenyl group, araalkenyl group, (C ₁ -C ₆ ) alkyl group substituted with a heterocyclic group, and (C ₁ -C ₆ ) substituted with a heterocyclic group Alkoxy (C ₁ -C ₆ ) alkyl group, acyloxy (C ₁ -C ₆ ) alkyl group, (C ₁
To C ₆ ) alkoxycarbonyloxy (C _{1 to} C ₆ ) alkyl group, aryloxycarbonyloxy (C ₁ to
C ₆ ) alkyl group, phenylcarbamoyloxy (C ₁ ~
C ₆₎ alkyl group, - an alkylene -N-R ₃ R _4, -N
—R ₃ R ₄ (wherein R ₃ and R ₄ are each independently a hydrogen atom, a (C ₁ -C ₆ ) alkyl group, an acyl group, (C ₁
To C ₆ ) alkoxycarbonyl group, substituted or unsubstituted phenoxycarbonyl group, (C ₁ -C ₆ ) alkylsulfonyl group, arylsulfonyl group or R ₃ and R ₄ together with the nitrogen atom have 5 or 6 members. Form a heterocycle of. However, the case where both R ₃ and R ₄ are hydrogen atoms is excluded. ) Is represented. ) A heat-sensitive transfer sheet comprising an ink layer containing a monoazo compound represented by the formula (4) supported on a support.