JP2001302637A - Heat sensitive transfer recording pigment and heat sensitive transfer printing sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To develop a heat sensitive transfer printing yellow pigment and a heat sensitive transfer printing sheet which are excellent in a color developing density and lightfastness. SOLUTION: This heat sensitive transfer printing sheet contains a compound (yellow pigment) represented by general formula (1) [wherein X1 is H, Cl, Br, nitro group or cyano group; X2 is H, Cl, methyl group or nitro group; X3 is H or methyl group; X4 is cyano group, carboxamide group or a carbalkoxy group; and R is an alkoxy alkoxyalkyl group].

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a novel azo compound and a thermal transfer sheet containing the same.

[0002]

2. Description of the Related Art In recent years, electrophotography, ink jet, thermal transfer and the like have been proposed as color recording techniques. Among them, the thermal transfer recording method is considered to be advantageous because maintenance and operation of the apparatus are easy. Heretofore, yellow dyes applied to thermal transfer recording have been selected from disperse dyes, oil-soluble dyes and the like. By the way, the dye used in the heat-sensitive transfer sheet is easily sublimated and diffused by the heat of the heat-sensitive recording head, and does not cause thermal decomposition, has a large molecular extinction coefficient,
Various quality characteristics are required, such as good color reproducibility, excellent clarity, heat resistance, light resistance, heat transferability, and no problem in safety and hygiene.

[0003]

According to the present invention, an image having excellent gradation and high color density can be obtained, and further excellent color reproducibility and excellent light resistance, weather resistance, heat resistance and heat transfer resistance. It is an object of the present invention to provide a thermosensitive transfer sheet having a color material layer containing a yellow dye having excellent color density and excellent light fastness, which can obtain an image record having high storability.

[0004]

Means for Solving the Problems As a result of intensive studies to find a heat-sensitive transfer sheet excellent in color density and light resistance, particularly a yellow heat-sensitive transfer sheet, the present invention has been accomplished. That is, the present invention provides (1) the following general formula (1)

[0005]

Embedded image

(In the formula (1), X ₁ represents a hydrogen atom, a chlorine atom, a bromine atom, a nitro group or a cyano group, X ₂ represents a hydrogen atom, a chlorine atom, a methyl group or a nitro group, and X ₃ represents a hydrogen atom. Or a methyl group, X ₄ represents a cyano group, a carboxamide group or an alkoxycarbonyl group, and R represents an alkoxyalkoxyalkyl group.)
(2) A heat-sensitive transfer sheet containing the compound represented by the general formula (1) described in (1).

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION In the compound of the above formula (1), X ₁ is a hydrogen atom, chlorine atom, bromine atom, nitro group or cyano group, and X ₂ is a hydrogen atom, chlorine atom, methyl group or X ₃ represents a hydrogen atom or a methyl group; X ₄ represents a cyano group, a carboxamide group or an alkoxycarbonyl group. Examples of the alkoxycarbonyl group include, for example, (C1-C1) such as a methoxy group and an ethoxy group.
4) A lower alkoxycarbonyl group. R represents an alkoxyalkoxyalkyl group. Examples of the alkoxyalkoxyalkyl group include (C1-C1) such as methoxyethoxyethyl group and methoxyethoxypropyl group.
4) Lower alkoxyalkoxyalkyl groups.

Next, specific examples of the compound of the formula (1) are shown in Table 1.

Table 1 Compound X ₁ X ₂ X ₃ X ₄ R λmax (nm) No. 1 H H H CN C3H6OC2H4OCH3 418 2 H H H CONH2 C2H4OC2H4OC2H5 408 3 H H H CN C3H6OC2H4OC2H5 418 4 H H H CN C3H6OC2H4OC4H9 418 5 H H H CN C2H4OC2H4OC3H7 418 6 H H H CONH2 C3H6OC2H4OCH3 407 7 H H H COOCH3 C2H4OC2H4OCH3 410 8 H H H CN C2H4OC3H6OCH3 418 9 H H H COOC2H5 C3H6OC2H4OCH3 412 10 CL CL H CN C3H6OC2H4OCH3 420 11 Br H H CN C3H6OC2H4OCH3 419 12 H NO2 H CN C3H6OC2H4OCH3 425 13 H H CH3 CN C3H6OC2H4OCH3 418 14 CN H H CN C3H6OC2H4OCH3 423 15 NO2 CH3 HCN C3 H6 OC2 H4 OCH3 426

In Table 1, the alkylene group and the alkyl group represented by R are linear. Λmax (nm) indicates a value in an acetone / water = 8: 2 (v / v) aqueous solution.

The compound of the formula (1) is, for example,
The 3-aminopyridine derivative (2) was diazotized by a known method according to the method described in
-Cyano-4-methyl-6-hydroxy-pyrido-2-
It is obtained by reacting with the on derivative (3) in an aqueous medium (coupling reaction).

[0012]

In the formulas (2) and (3), X ₁ , X ₂ , X ₃ ,
X ₄ and R have the same meanings as described above.

The heat-sensitive transfer sheet of the present invention is a yellow heat-sensitive transfer sheet having a color material layer containing at least one compound represented by the above formula (1) on a support. The thermal transfer sheet of the present invention is manufactured, for example, as follows. That is, a yellow ink is prepared by dissolving or dispersing the compound represented by the general formula (1) in a medium together with a binder in a medium, and the ink is formed into a sheet form such as a plastic film or paper. The yellow heat-sensitive transfer sheet of the present invention is produced by coating on a support and drying. As a binder for preparing the ink, for example, a cellulosic,
Acrylic acid-based, starch-based water-soluble resins, acrylic resins, methacrylic resins, polystyrene resins, polycarbonate resins, polysulfone resins, polyester resins, polyethersulfone resins, and organic solvent-soluble resins such as ethylcellulose. Or two or more kinds are used in combination.

As a medium for preparing the ink, water; alcohols such as methanol, ethanol, isopropyl alcohol and butanol; cellosolves such as methyl cellosolve and ethyl cellosolve; ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; Aromatic hydrocarbons such as toluene, xylene and chlorobenzene; methylene chloride, chloroform,
Chlorinated solvents such as dichloroethane and trichloroethane; acetates such as ethyl acetate and butyl acetate; ethers such as tetrahydrofuran and dioxane;
An organic solvent such as N-dimethylformamide, N-methylpyrrolidone, dimethylimidazolidinone or the like;
Used as a mixture of more than one species.

As the support on which the ink is applied to prepare the heat-sensitive transfer sheet, a condenser paper, cellophane, or a plastic film having good heat resistance such as polyester, polyamide, polyimide, or polyethersulfone is used. The thickness is preferably about 3 to 50 μm.

The ink can be applied onto the support by using a bar coater, a roll coater, a knife coater, a gravure printing machine, or the like. The thickness of the ink coating layer after drying is 0.1 to 10 μm, preferably 0.4 to 10 μm.
It is applied so as to have a thickness of 5.0 μm.

Next, the ratio of the compound of the general formula (1), the binder and the medium in the ink is usually 0.5
-15% by weight, binder 3-15% by weight, medium 70-9
6.5%, preferably 1 to 10% by weight of pigment, 4 to binder
12% by weight and 78-95% by weight of the medium.

The yellow heat-sensitive transfer sheet of the present invention is used together with a receiving sheet. Examples of the receiving sheet include papers 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, which are usually used as receiving sheets. Can be used as is.

The transfer of the dye from the yellow heat-sensitive transfer sheet of the present invention to the receiving sheet is carried out, for example, by a thermal printer (for example, Thermal Printer TN-540 manufactured by Toshiba Corporation).
0) or the like by a recording device such as 1 to 30 ms.

[0021]

Next, 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 for Preparing Ink Compound No. 1 shown in Table 1 above was used. 1 yellow pigment (λma
x 418 nm: 2 parts of methylene chloride) and 6 parts of ethyl cellulose, 45 parts of toluene, 45 parts of methyl ethyl ketone
Parts of the mixture was processed using a ball mill for 3 hours to prepare an ink composition.

2) Preparation of Transfer Sheet The above ink composition was applied to a 4 μm polyethylene terephthalate (PET) film to a dry film thickness of 1 μm using a bar coater and dried to obtain a transfer sheet.
No precipitation of dye was observed on the dried ink layer.

3) Preparation method of receiving sheet The receiving sheet is 15 parts of a polyester resin (manufactured by Nippon Gosei Co., Ltd., product name: TP-220), amino-modified silicone (manufactured by Shin-Etsu Chemical Co., Ltd., product name: KF393) 0.5
Part, 20 parts of methyl ethyl ketone, and 10 parts of xylene, was applied to 150 μm synthetic paper (manufactured by Oji Yuka Co., Ltd., product name: FPG-150) so as to have a dry film thickness of about 5 μm and 100 ° C. for 30 minutes After curing, a receiving sheet was prepared.

4) Transfer Recording The ink-coated surface of the transfer sheet was overlapped with the receiving sheet, and transfer recording was performed under the following conditions to evaluate. The recording conditions were a print pulse width of 1 to 16 msec / line, an applied voltage of 1.0 V, a print cycle of 30 msec / line, a constant applied voltage, a printing time (applied energy) on the horizontal axis, an optical density (O
D value) was taken as a vertical axis to obtain a color density curve. The maximum color density was calculated from the color density curve.
The color density was measured using a densitometer RD-914 (manufactured by Macbeth, USA). As a result, the maximum color density was 1.55. Also, the light resistance is good. Synthesis Example Compound No. used in this example was prepared. No. 1 was synthesized as follows. 17.6 parts of 3-aminopyridine were dissolved in 250 parts of an 8% by weight aqueous hydrochloric acid solution, and sodium nitrite was added at 0 to 5 ° C.
Diazotization is carried out in a conventional manner using 13.0 parts to obtain a diazotized solution of 3-aminopyridine. Separately, 41.5 parts of 1,2-dihydro-6-hydroxy-1- (3- (2-methoxyethoxy) propyl) -4-methyl-2-oxo-3-pyridinecarbonitrile is dissolved in 40 parts of water. ,
Prepare coupler solution. The diazotized solution is added dropwise to the coupler solution at 0 to 5 ° C. while maintaining pH 5 to 8,
Initiate the coupling reaction. The resulting yellow compound was filtered, washed with water, and dried to obtain Compound No. 1 (yellow dye, λmax 418 nm: in methylene chloride solution) 4
6.5 parts are obtained. The obtained compound was confirmed by IR, MASS and NMR.

Examples 2 to 9 Inks were prepared in the same manner as in Example 1 using 2 parts of each of the compounds shown in Table 1 which were synthesized in the same manner as in the synthesis example in Example 1, and then a transfer sheet was prepared. . After transfer recording was performed using these transfer sheets in the same manner as in Example 1, the color density was measured. As a result, as shown in Table 2 below, a high maximum color density was obtained as in Example 1.

Table 2 Example (Compound No.) Maximum color density 2 (No. 2) 1.493 (No. 3) 1.504 (No. 4) 1.485 (No. 5) 1. 496 (No. 6) 1.467 (No. 7) 1.458 (No. 8) 1.479 (No. 9) 1.46 10 (No. 10) 1.47 11 (No. 12) 1.48 12 (No. 13) 1.49 13 (No. 14) 1.47 14 (No. 15) 1.49

[0028]

According to the thermal transfer recording of the present invention, a yellow image having excellent gradation and extremely high color density can be obtained. Furthermore, since the color reproducibility is good and the light resistance, weather resistance, heat resistance, and heat transfer resistance are excellent, an image can be recorded with high storability.

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H111 AA27 AA33 BA39 BA49 BA75 4C055 AA04 AA10 BA03 BA42 CA03 CA54 CA57 CA58 CA59 CB01 CB02 CB17 DA05 DA06 EA01

Claims (2)

[Claims] (1) The following general formula (1): (In the formula (1), X ₁ is a hydrogen atom, a chlorine atom, a bromine atom,
A nitro group or a cyano group, X ₂ represents a hydrogen atom, a chlorine atom,
X ₃ represents a hydrogen atom or a methyl group; X ₄ represents a cyano group, a carboxamide group or an alkoxycarbonyl group; and R represents an alkoxyalkoxyalkyl group. ) 2. A heat-sensitive transfer sheet containing the compound represented by the general formula (1) according to claim 1.