JPH0243093A - Sublimating transfer recording anthraquinone dye - Google Patents

Abstract

PURPOSE:To make a sublimating transfer amount of a dye controllable to facilitate a gradation recording by using a specific anthraquinone cyan dye, and changing an energy to bed applied to a thermal head at the time of thermal transfer. CONSTITUTION:As a cyan sublimating transfer recording dye, a compound shown by a general formula (I) is used. In this construction, all requirements, such as heat resistance, light resistance, sublimating speed, hue, and ribbon stability, can be met. But, in the formula, R1 represents either straight-chain or branched lower alkyl group, cycloalkyl group, alkenyl group, aryl group, aralkyl group, and alkoxyalkyl group; and R2, R3, R4 represent hydrogen atom, either straight-chain or branched lower alkyl group, alkoxy group, and alkenyl group with the exception that all of them are the same, any of them is a hydrogen atom and the other two are the same, or two of them are hydrogen atoms.

Description

Detailed Description of the Invention In the formula c, R1 represents a lower alkyl group, a cycloalkyl group, an alkenyl group, an aryl group, an aralkyl group, or an alkoxyalkyl group λ, which may be linear or branched, and R1, R5
, R4 represents a hydrogen atom, a lower alkyl group, an alkoxy group, or an alkenyl group that may be linear or branched, and when all are the same, and when any one is a hydrogen atom and the other two are the same, or except when two are hydrogen atoms.

] is provided.

[Prior art and problems to be solved by the invention] Thermal transfer methods using sublimable dyes apply sublimable dyes in the form of ink to a thin condenser paper or PET film several microns thick, and select this with a thermal head. This is one of the thermal transfer printing methods in which the image is heated and transferred onto recording paper, and is currently used as a means for recording (hard copy) various types of image information. The sublimable dye used for this is a coloring material that changes directly from the solid phase into gas molecules when heated, and firmly dyes the dyed material. Until now, it has been mainly used for dyeing polyester fibers, fabrics, etc. Many of them have been developed. Sublimable dyes are characterized by a relatively rich variety of colors, excellent color mixing properties, strong dyeing power, and relatively high stability; however, the amount of ink that sublimates depends on thermal energy, and the density after dyeing It has a great feature that other printing methods do not have in that it can be controlled in an analog manner.

However, there are very few dyes that have been proposed so far that satisfy all the conditions such as heat resistance, light resistance, sublimation speed, hue, ribbon stability, etc., and it is difficult to find a dye that satisfies the optimal conditions as a sublimable dye. has been expected.

[Means to solve the problem]

As a result of intensive studies to solve the above problems, the present inventors discovered a compound represented by the above formula (I) and completed the present invention.

That is, the present invention provides the following general formula (I) [wherein R1 represents a straight or branched lower alkyl group, cycloalkyl group, alkenyl group, aryl group, aralkyl group, or alkoxyalkyl group, R2, R3,
R4 represents a hydrogen atom, a lower alkyl group, an alkoxy group, or an alkenyl group that may be linear or branched, and all of them are the same, or one of them is a hydrogen atom and the other two are the same, or Except when two are hydrogen atoms. ]
This is an anthraquinone dye for sublimation transfer recording represented by:

The present invention will be explained in detail below.

In the present invention, R3 is a lower alkyl group such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a tert-butyl group, a cycloalkyl group such as a cyclohexyl group, a cyclopentyl group, a propenyl group, a butenyl group. alkenyl groups such as phenyl groups, methylphenyl groups, aryl groups such as hydroxyphenyl groups, aralkyl groups such as hensyl groups and phenethyl groups, methoxymethyl groups,
Examples include alkoxyalkyl groups such as methoxyethyl group, ethoxymethyl group, and ethoxyethyl group, R2, R1,
R4 is a hydrogen atom, or a methyl group, ethyl group, propyl group, isopropyl group, butyl group, isobutyl group, tert
Examples thereof include lower alkyl groups such as -butyl group, alkoxy groups such as methoxy group, ethoxy group, and propoxy group, and alkenyl groups such as vinyl group, flobenyl group, and futhynyl group.

Regarding the combination of R2, R1, and R4, there are cases where all of them are the same group, cases where one of them is a hydrogen atom and the other two groups are the same, or cases where the two groups are hydrogen atoms. It is a combination excluding.

The dye represented by formula (I) of the present invention can be produced by a conventional method.
Using 1-amino-4-bromoanthraquinone-2=carboxylic acid as a raw material, it is esterified through acid chloride to form R
2.Rs and Ra can be easily obtained by a method of condensing a predetermined group with the indicated aniline.

As a method for producing a thermal transfer recording ink using the dye of the present invention, the dye may be mixed with a suitable resin, solvent, etc. to prepare the recording ink.

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 adjusting 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 alkynd-based, nitrocellulose-based, and alkyl celluloses, or water-based resins such as maleic acid-based, acrylic acid-based, casein, Sierran, and glue can be used. In addition, as a solvent for ink adjustment,
Alcohols such as methanol, ethanol, propatool, butanol, cellosolves such as methyl cellosolve, ethyl cellosolve, aromatics such as henzene, toluene, xylene, esters such as ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, cyclohexanone, etc. Ketones, hydrocarbons such as ligroin, cyclohexane, kerosene, dimethylformamide, etc. can be used, but when using an aqueous resin, water or a mixture of water and the above-mentioned solvents can also be used.

Suitable substrates for applying ink include thin paper such as condenser paper and glassine paper, and films made of plastics with good heat resistance such as polyester, polyamide, and polyimide. In order to improve heat transfer efficiency to the dye, a thickness of about 5 to 50 μm is appropriate.

Examples of recording materials include polyolefin resins such as polyethylene and polypropylene, halogenated polymers such as polyvinyl chloride and polyvinylidene chloride, vinyl polymers such as polyvinyl alcohol, polyvinyl acetate, and polyacrylic ester, polyethylene terephthalate, and polyethylene terephthalate. Polyester resins such as butylene terephthalate, polystyrene resins, polyamide resins, copolymer resins of olefins such as ethylene and propylene and other vinyl monomers, ionomers, cellulose resins such as cellulose diacetate and cellulose triacetate, polycarbonates, Fibers made of polysulfone, polyimide, etc.
Examples include woven fabrics, films, sheets, and molded products.

Particularly preferred are woven fabrics, sheets or films made of polyethylene terephthalate.

In addition, in the present invention, plain paper coated or impregnated with acidic fine particles such as silica gel added to the resin, paper laminated with a resin film, or special processed paper treated with acetylation are used. By doing so, good recording with excellent image stability under high temperature and high humidity conditions can be achieved. It is also possible to use films of various resins or synthetic papers made from them.

Furthermore, after the transfer recording, for example, a polyester film is hot-pressed and laminated on the transfer recording surface, thereby improving the color development of the dye and stabilizing the storage of the recording.

(Functions and Effects) The anthraquinone cyan dye represented by the general formula (+) of the present invention can control the sublimation transfer amount of the dye by changing the energy given to the thermal head during thermal transfer. Easy to record and suitable for full color recording.

Furthermore, since it is stable against heat, light, moisture, chemicals, etc., it does not undergo thermal decomposition during transfer recording, and the obtained recording has excellent storage stability.

Furthermore, since the pigment of the present invention has good solubility in organic solvents and good dispersibility in water, it is easy to prepare a uniformly dissolved or dispersed ink with high concentration, resulting in good color density. It is a dye that is of practical value as it allows you to obtain accurate records.

(Example) Hereinafter, the present invention will be explained in detail with reference to Examples. Parts in examples indicate parts by weight.

Example = 1 A compound of the following formula was synthesized according to a conventional method, and ink was adjusted, a transfer sheet, and a recording material were prepared as described below, and transfer recording was performed. Maximum absorption wavelength (λ) of the compound in chloroform
-ax) was 660 nm.

(i) Preparation method of ink Pigment of the above formula (^) 3-part polybutyral resin 4.5〃Methyl ethyl ketone
46.25#Toluene
46.25 The pigment mixture having the above composition was mixed with a paint conditioner for about 30 minutes using a glass piece to condition the ink.

(I1) Method for creating a transfer sheet Using a gravure proofing machine (plate depth 30 μl11), apply the above ink to a 98-part thick polyethylene terephthalate film whose back side has been heat-resistant treated at a dry coating amount of 1.0 g/nf.
Apply it and let it dry.

(iii) Preparation of recording material Polyester resin 0.8 parts (vy
lon 103 Toyobo Tg=47°C) EVA polymer plasticizer 0.2 parts (Elvaloy 74
1p Mitsui Polychemical Tg・-37°C) Amino modified silicone 0.04 part (KF
-857 Shin-Etsu Chemical Co., Ltd.) Epoxy modified silicone 0.04 part (KF
-103 manufactured by Shin-Etsu Chemical Co., Ltd.) Methyl ethyl ketone / toluene / cyclohexane (weight ratio 4:4:2) 9.0 parts or more were mixed, a coating liquid was adjusted, and a bar was applied to synthetic paper (manufactured by Clove Yuka, Yupo FPGl150). Coater (RK Pr1nt
Coat Instruments Co., Ltd., No. 1) was used to apply the coating at a dry rate of 4.5 g/rd, and the coating was dried at 100°C for 15 minutes.

(iv) Transfer recording The above-mentioned transfer sheet and the above-mentioned recording material are placed one on top of the other with their respective ink-coated surfaces and coating liquid-coated surfaces facing each other, and a thermal head is applied from the back side of the thermal transfer sheet with a voltage of 10 V and a printing time of 4. Recording was performed under conditions of .0 milliseconds, and the color density was 1.8.
3 cyan records were obtained.

The color density was measured using a densitometer R manufactured by McHess, USA.
Measured using D-514 type (filter: Lasoten N (I58)).

Color density was calculated using the following formula.

Color density = log. (Io/I) 1o = Intensity of reflected light from standard white reflector ■ - Intensity of reflected light from test object In addition, the light resistance test of the obtained record was performed using a xenon fade meter (manufactured by Suga Test Instruments Co., Ltd.). ) at a black panel temperature of 63±2°C, there was almost no discoloration after 40 hours of irradiation, and the image stability was excellent even under high temperature and high humidity.

In addition, the fastness was determined by the sharpness of the image and the coloring when the surface was rubbed with white paper after the recorded image was left in an atmosphere at 50°C for 48 hours. In addition, the white paper was not colored either, and the fastness of the recorded image was good.

Examples 2 to 9 Anthraquinone-based anthraquinone color pigments shown in Table 1 were produced according to the same method as in Example 1, and ink adjustment, transfer sheet preparation, recording material preparation, and transfer recording were carried out in the same manner. The results shown in Table 1 were obtained.

All of these records were subjected to a light fastness test in the same manner as in Example 1, and the records showed almost no change and were excellent in image stability under high temperature and high humidity conditions.

Further, a fastness test was conducted in the same manner as in Example 1, but the sharpness of the image did not change, the white paper did not become colored, and the fastness of the recorded image was good.

(Margin below) Table-1

Claims (1)

[Claims] 1) The following general formula (I) ▲ Numerical formulas, chemical formulas, tables, etc. are included ▼ (I) [In the formula, R_1 is a lower alkyl group, a cycloalkyl group, or an alkenyl group that may be linear or branched. group, aryl group, aralkyl group, alkoxyalkyl group, R_2, R
_3 and R_4 represent a hydrogen atom, a lower alkyl group, an alkoxy group, or an alkenyl group that may be linear or branched;
except when they are the same or when they are hydrogen atoms. ] Anthraquinone dye for sublimation transfer recording.