JPS6031563A - Tricyano dye for thermal transfer recording - Google Patents

Abstract

NEW MATERIAL:Compds. of formula I (wherein R<1>, R<2> are each lower alkyl, aralkyl, aryl, cyclohexyl, halogeno-lower-alkyl, lower-alkoxy-lower-alkyl, lower- alkoxy-lower-alkoxy-lower-alkyl, hydroxy-lower-alkyl, cyano-lower-alkyl, tetrahydrofurfuryl, aralkyloxy-lower-alkyl, aryloxy-lower-alkyl, etc.; R<1> and R<2> do not represent lower alkyl simultaneously). USE:Clear magenta tricyano dye for thermal transfer recording. PREPARATION:Anilines of formula II are reacted with tetracyanoethylene in an org. solvent.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tricyano dye for thermal transfer recording.

Currently, the TV, CRT color display, and color fan stains 2. A dye sublimation thermal transfer recording method has been proposed as a method for obtaining color hard copies from magnetic cameras and the like.

In this method, a transfer sheet coated with a sublimable dye is heated with a thermal recording head to sublimate and transfer the dye to the recording medium to obtain a color record, but by adjusting the energy applied to the thermal head, the dye Since the amount of sublimation can be controlled, it is easy to express gradation, and compared to other recording methods, it is especially advantageous for obtaining full-color hard copies.

By the way, the dye used in this recording method must meet the following conditions.

■ Easily sublimated under the operating conditions of the thermal recording head.

■Do not thermally decompose under the operating conditions of the thermal recording head.

■ It must have a favorable hue in terms of color reproduction.

■ Large molecular extinction coefficient.

■ Stable against light, moisture, chemicals, etc.

■ Easy to synthesize.

The object of the present invention is to provide a magenta dye that particularly satisfies (1), (2), and (2) among the necessary conditions for a dye used in the above-mentioned thermal recording method.

That is, the present invention has the following general formula (1) (wherein R1 and R2 are lower alkyl groups, aralkyl groups,
Aryl group, cyclohexyl group, halogeno lower alkyl group, lower alkoxy lower alkyl group, lower alkoxy lower alkoxy lower alkyl group, hydroxy lower alkyl group, cyanogen lower alkyl group, tetrahydrofurfuryl group, aralkyloxy lower alkyl group, aryloxy lower alkyl group group, alkenyloxy lower alkyl group, tetrahydrofurfuryloxy lower alkyl group, lower alkoxycarbonyl lower alkyl group, lower alkylcarbonyloxy lower alkyl group, lower alkoxycarbonyloxy lower alkyl group. However, R' and R2 do not have a lower alkyl group at the same time. ) The gist thereof is a tricyano-based heat-sensitive transfer recording dye represented by:

R1 and R2 represented by the forepaw general formula (1) include a methyl group, an ethyl group, a linear or branched propyl group,
Lower alkyl groups such as butyl groups; aralkyl groups such as phenethyl, be/cyl, and phenylpropyl groups; aryl groups such as phenyl and p-chlorophenyl groups; fluorohexyl groups; methoxyethyl, ethoxyethyl, and p- Lower alkoxy lower alkyl groups such as poxyethyl group, butoxyethyl group, r-methoxybutyl group; Lower alkoxy lower alkyl groups such as methoxyethoxyethyl group, ethoxyethoxyethyl group, prozoxyethoxyethyl group; hydroxyethyl group , β-hydroxypropyl group, β-hydroxybutyl group; halogeno-lower alkyl groups such as chloroethyl group, chloropropyl group, bromoethyl group, iodoethyl group; cyanomethyl group, cyanethyl group, cyanopropyl group, etc. Cyano lower alkyl group; Tetrahydrofurfuryl group Alkenyloxy7 lower alkyl group such as sialyloxyethyl group and comethylallyloxyethyl group; Aryloxy lower alkyl group such as phenyloxyethyl group and p-chlorophenyloxyethyl group: Pen 72-rukyloxy lower alkyl groups such as zyloxyethyl group and 7enethyloxyethyl group; methoxycarbonylethyl group, ethoxycarbonylethyl group, tetrapoxycarbonylethyl group,
Lower alkoxycarbonyl lower alkyl groups such as methoxycarbonylmethyl group and ethoxycarbonylmethyl group; acetoxyethyl group, propionyloxyethyl group, β-
Lower alkylcarbonyloxy lower alkyl groups such as acetoxypropyl group and β-acetoxybutyl group; Methoxycarbonyloxyethyl group; Lower alkoxycarbonyloxy lower alkyl groups such as ethoxycarbonyloxyethyl group; Tetrahydro such as tetrahydrofur7lyloxy7ethyl group; The furfuryloxy lower alkyl group is removed.

Particularly preferable R1 and R2 are C8~, alkyl group,
Phenethyl group, γ-methoxybutyl group, chloroethyl group, benzyl group, methoxyethyl group, methoxyethoxyethyl group, cyanoethyl group, tetrahydrofurfuryl group,
Examples thereof include a phenyl group, a cyclohexyl group, a phenethyloxyethyl group, a phenoxyethyl group, an allyloxethyl group, a tetrahydrofuryl7lyloxethyl group, and a hydroxyethyl group.

The method for producing the dye of the present invention includes adding tetracyanoethylene to an aniline represented by the following general formula () (in which R1 and R2 have the same meanings as in the above general formula [I]) in an organic solvent. It can be easily obtained by reacting with t-F, which precipitates after the reaction. In case J9 that the target product does not precipitate after the reaction, the target product can be precipitated by adding a solvent with low solubility for the target product, water, or the like. Furthermore, the target product can be purified by conventional means such as recrystallization or column chromatography, if necessary.

A method for producing a thermal transfer recording ink using the dye of the present invention involves mixing the dye with a suitable resin.

The recording ink may be prepared by mixing with a solvent, water, etc. In addition, as a thermal transfer method, the ink obtained above is applied onto a suitable base material to create a transfer sheet, the sheet is placed on the recording medium, and then heated and pressed from the back side of the sheet with a thermal recording head. In this way, the dye on the sheet is transferred onto the recording medium.

The resin used for preparing the above ink may be those used in ordinary printing inks, such as rosin-based, phenol-based, xylene-based, petroleum-based, vinyl-based, polyamide-based,
Oil-based resins such as alkyd-based, nitrocellulose-based, alkylcellulose, and alkylcellulose4) 4 or water-based resins such as maleic acid-based, acrylic acid-based, casein, shellac, and glue can be used. In addition, as solvents for ink preparation, alcohols such as methanol, ethanol, propatool, and butanol, cellosolves such as methylceronelube and ethyl cellosolve, aromatics such as benzene, toluene, and xylene, ethyl acetate, and acetic acid are used. Esters such as butyl, ketones a such as acetone, methyl ethyl ketone, and cyclohexanone, hydrocarbons such as vy loin, cyclohegythane, and kerosene, dimethylformamide, etc. can be used. However, when using an aqueous resin, water or water can be used. It is also possible to use a mixture of and the above-mentioned solvents.

The base material to which the ink is applied is condenser paper,
Thin paper such as thin paper, and films of plastics with good heat resistance such as polyester, polyamide, and polyimide are suitable; A certain thickness is appropriate.

Ordinary paper can also be used as the recording medium, but in order to improve the color development of the dye, it may be coated or impregnated with a resin that has good compatibility with the dye, or it may be laminated with a resin film. Good recording can be achieved by using paper or special processed paper that has been treated with acetylation. It is also possible to use films of various resins or synthetic papers made from them.

Furthermore, by heat-pressing and laminating, for example, a polyester film on the transfer recording surface after transfer recording, it is possible to improve the color development of the dye and to stabilize the recording during storage.

Since the dye of the present invention has a clear magenta color, for example, the yellow dye represented by the following structural formula and the following structural formula ONHC
H.

Suitable for obtaining full color in combination with cyan dye represented by

The above yellow pigment is N-methyl-3-cyano-4-
It is easily obtained by diazotization coupling of aniline to methyl-6-hydroxy-pyridone.

The above-mentioned cyan dye can be obtained by reacting /-aminococarboxymethylaminoanthraquinone with methanol in sulfuric acid.

This invention will be specifically explained below with reference to examples, but these examples are not intended to limit the invention.

Example / 1) Production of dye
-dimethylborumamide/! After adding tetracyanoethylene J, & Hirop to this, about s
After reacting for 7 hours under OC, the reaction solution was cooled to room temperature, 60ml of methanol was added, and the precipitated dark red crystals were filtered, washed with methanol and water, and dried to obtain the dye with the following structural formula, g3, P. Ta. 4F4P・q to Q・Ryusee#
oat 豐＃＃＃＃＃＃＃＃? ? #The melting point of this dye is
/nige~/koAU, m/e in the mass spectrum
= 326 parent ion peaks were shown. Also, in the visible absorption spectrum in chloroform! r, 2A
It showed a maximum absorption value at nm.

11) Method for preparing ink for thermal transfer recording The ink is prepared by mixing the dye mixture obtained in the above 1) above with a paint conditioner using glass beads for about 30 minutes. did.

111) Method for creating transfer sheet The above ink was applied to condenser paper (10 μm) using a gravure proofing machine (plate depth: 3 μm).

iV) Method for making image-receiving paper Aqueous dispersion of saturated polyester 3-layer polyester (Pyronal MD-7, 2oo manufactured by Toyobo Co., Ltd.) / oy
and calcium bicarbonate (Maruo Calcium Manufacturing Super I,
soo ) tθ wt % water slurry s' o y was mixed and the prepared paint was coated on high-quality paper (thickness 200 μm) using a bar coater (RK Pr1nt qoat Instr.
It was coated using a commercially available product (manufactured by Uments Inc.).

■) Transfer recording method Lay the ink-coated side of the transfer sheet on the paint-coated side of the image-receiving paper, and then! Using a thermal head with a 0Ω heating resistor at the density of Dadot, thermal transfer recording is performed to achieve a color density of 1.
A magenta color record of 1.2θ was made. At this time, a voltage of /gV was applied to the thermal head for 6 milliseconds.

The color density was measured using a densitometer R manufactured by Macbeth Co., Ltd. in the United States.
It was measured using D-5/Da type (filter: Ratten 16!; g).

Color density was calculated using the following formula.

Color density = lo #1 (1 (IO/I ) ■ 0: Intensity of reflected light from standard white reflector I: Intensity of reflected light from test object In addition, the light resistance test of the obtained record was performed on carbon This was carried out using an arc fade meter (manufactured by Suga Test Instruments Co., Ltd.) (black panel temperature: 63 °C), but there was almost no discoloration during qo waiting time irradiation.

Example 1 Using the dye λF shown in Table 1, ink was prepared, a transfer sheet and image receiving paper were prepared, and transfer recording was performed in the same manner as in Example 1, resulting in a magenta color with the color density shown in the first column. Obtained a record of. All of these records were tested for light resistance in the same manner as in Example 1, and the I-hills showed almost no discoloration.

Claims (1)

[Claims] (1) General formula] (In the formula, R1 and R2 are lower alkyl groups, aralkyl groups,
Aryl group, cyclohexyl group, halogeno lower alkyl group, lower alkoxy lower alkyl group, lower alkoxy lower alkoxy lower alkyl group, hydroxy lower alkyl group, cyanogen lower alkyl group, tetrahydrofurfuryl group, aralkyloxy lower alkyl group, aryloxy lower alkyl group group, alkenyloxy lower alkyl group, tetrahydrofurfuryloxy lower alkyl group, lower alkoxycarbonyl lower alkyl group, lower alkylcarbonyloxy lower alkyl group, lower alkoxycarbonyloxy lower alkyl group. However, R1 and R2 do not have a lower alkyl group at the same time. ) Tricyano-based thermal transfer recording dye.