JPH0725169A - Dye for thermal transfer recording, ink composition for thermal transfer recording, and transfer sheet - Google Patents

Abstract

PURPOSE:To prepare an ink compsn. for thermal transfer recording having a high sublimation speed by compounding an yellow sublimable dye represented by a specific general formula, a binder resin and an org. solvent and/or water. CONSTITUTION:A phthalimide compd. represented by formula I (wherein R1 is H, an alkyl group, a cycloalkyl group, an alkoxyalkyl group or a halogenoalkyl group) is diazotized and subsequently coupled with a pyridone compd. represented by formula II (wherein R2 is same to R1 of the formula I) to synthesize a dye for thermal transfer recording represented by formula III (wherein R1 and R2 are same as the formulae I, II). This dye for thermal transfer recording and a binder resin are dispersed in an org. solvent and/or water to prepare an ink compsn. which is, in turn, applied to one surface of a base material sheet and dried to form a dye support layer to obtain a transfer sheet. As a concrete example of a resin for preparing the ink compsn., a rosin or phenol type oily resin is designated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermal transfer recording dye (hereinafter abbreviated as sublimation dye) used for color hard copy by a thermal transfer recording system, a thermal transfer recording ink composition and a transfer sheet.

[0002]

2. Description of the Related Art A thermal transfer system using a sublimation dye is a recording paper which is obtained by applying an ink-made sublimation dye to a thin condenser paper or PET film having a thickness of several microns and selectively heating it with a thermal head to sublimate it. It is one of the thermal transfer printing methods in which the image is transferred onto the image recording medium, and is currently used as a means for image recording (hard copy) of various image information. The sublimation dyes used here are characterized by abundant colors and excellent color mixing properties, strong dyeing power and relatively high stability, but in the thermal transfer recording system, the amount of dyes sublimated depends on thermal energy. However, in that the density after dyeing can be controlled in an analog manner, it has a great feature not found in other printing methods.

As a conventional yellow sublimation dye,
A large number of quinophthalone compounds having excellent light resistance and fastness (Japanese Patent Laid-Open Nos. 60-53565, 63-189289, 63-182192) have been proposed, but the sublimation rate and after transfer At present, there is a demand for further improvement in terms of image stability of the above.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a dye for thermal transfer recording, an ink composition for thermal transfer recording, and a transfer sheet which have a high sublimation rate and image stability after transfer. is there.

[0005]

Means for Solving the Problems The inventors of the present invention have made extensive studies as a result of solving the above problems, and as a result, the following general formula (1)
The present invention has been completed by finding that the compound represented by the formula (3) can be an excellent yellow sublimation dye. That is, the present invention provides the following general formula (1)

[0006]

[Chemical 2] [In the formula, R ₁ and R ₂ are a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxyalkyl group, a halogenoalkyl group, a cyanoalkyl group, a hydroxyalkyl group, an alkenyl group, an aralkyl group, a substituted or unsubstituted aryl group. , An alkoxycarbonyl group, an alkoxycarbonylalkyl group or an alkoxyalkoxycarbonylalkyl group. ] A thermal transfer recording dye represented by the following, a transfer recording ink composition containing the binder resin and an organic solvent and / or water, and a base sheet and a dye carrying formed on one surface of the base sheet. The present invention relates to a transfer sheet comprising a layer and the dye contained in the dye-supporting layer is the above dye.

In the study of the present inventors, it is generally found that in sublimation dyes, the sublimation rate at the time of transfer is related to the interaction between the dye molecules and the interaction between the dye molecules and the binder resin for ink. Was given.

That is, it is most preferable that the dye has good solubility in the ink solvent and has a low melting point, and that the interaction with the binder resin for the ink is so small as not to impair the storage stability after ribbon production. It became clear that it was a different pigment.

The sublimation dye represented by the general formula (1) of the present invention has the above-mentioned various conditions and can obtain an extremely good sublimation rate.

The present invention will be described in detail below.

In the general formula (1), the phthalimide ring is preferably azo-bonded at the 3-position or 4-position. R ₁ ,
R ₂ is a hydrogen atom, methyl, ethyl, n-propyl, i
Alkyl groups having 1 to 8 carbon atoms such as so-propyl, n-butyl, iso-butyl, n-pentyl, n-hexyl, n-heptyl, and n-octyl, and 5 to 6 carbon atoms such as cyclopentyl and cyclohexyl. A cycloalkyl group of 2
-Methoxyethyl, 2-ethoxyethyl, 2-n-propoxyethyl, 2-n-butoxyethyl, 3-ethoxypropyl, 3-n-propoxypropyl and the like has 1 to 4 carbon atoms of alkoxy, and the number of carbon atoms of alkyl. Is an alkoxyalkyl group having 2 to 3, chloromethyl, 2-chloroethyl,
A halogenoalkyl group having 1 to 3 carbon atoms such as 2-chloropropyl and 3-chloropropyl, a cyanoalkyl group having 1 to 2 carbon atoms such as cyanomethyl and 2-cyanoethyl, hydroxymethyl, 2-hydroxyethyl, 3-
A hydroxyalkyl group having 1 to 3 carbon atoms such as hydroxypropyl, an alkenyl group having 3 to 4 carbon atoms such as allyl, 2-butenyl and 3-butenyl, and a carbon number of 7 to 9 such as benzyl and phenethyl. A substituted or unsubstituted aryl group such as aralkyl group, phenyl, o-tolyl, m-tolyl, p-tolyl, o-chlorophenyl, m-chlorophenyl, p-chlorophenyl, methoxycarbonyl, ethoxycarbonyl, n-propoxycarbonyl,
Alkoxycarbonyl groups having 1 to 8 carbon atoms in alkyl such as iso-propoxycarbonyl, n-butoxycarbonyl, iso-butoxycarbonyl, sec-butoxycarbonyl, tert-butoxycarbonyl, n-pentyloxycarbonyl, n-hexyloxycarbonyl. , Methoxycarbonylmethyl, ethoxycarbonylmethyl, n-propoxycarbonylmethyl, iso-propoxycarbonylmethyl, n-butoxycarbonylmethyl, iso-butoxycarbonylmethyl, sec-butoxycarbonylmethyl, tert-butoxycarbonylmethyl, n-pentyloxycarbonyl Alkoxycarbonylalkyl group having 1 to 6 carbon atoms of alkoxy such as methyl and n-hexyloxycarbonylmethyl, and having 1 to 2 carbon atoms of alkyl. 2-methoxy-ethoxycarbonylmethyl, 2-ethoxy-ethoxycarbonylmethyl, 2-
n-propoxyethoxycarbonylmethyl, 2-iso
Examples thereof include an alkoxyalkoxycarbonylalkyl group having an alkoxy having 1 to 4 carbon atoms and an alkyl having 1 to 2 carbon atoms, such as propoxyethoxycarbonylmethyl and 2-n-butoxyethoxycarbonylmethyl.

The method for producing the dye represented by the general formula (1) of the present invention includes the general formula (2)

[0013]

[Chemical 3] [In formula, R < ₁ > is the same as the said definition. ] After the diazotization of the phthalimide compound represented by the general formula (3)

[0014]

[Chemical 4] [In the formula, R ₂ is the same as defined above. ] The compound shown by General formula (1) can be manufactured by coupling with the pyridone compound shown by these.

As a method for producing a thermal transfer recording ink using the dye of the present invention, the dye may be mixed with an appropriate resin, solvent or the like according to a conventional method to prepare the recording ink.
In this case, the amount of dye in the thermal transfer recording ink is usually 2
~ 5% by weight.

As the thermal transfer method, the ink obtained by the above method is applied onto a suitable substrate to prepare a transfer sheet, the sheet is superposed on a recording material, and then thermal recording is performed from the back surface of the sheet. A method of heating and pressing with a head according to a recording pattern can be mentioned, and in that case, the dye on the sheet is transferred onto the recording material.

The resin for preparing the above-mentioned ink may be any resin used in ordinary printing inks, such as rosin-based, phenol-based, xylene-based, petroleum-based, vinyl-based, polyamide-based, alkyd-based, nitrocellulose. Oil-based resins such as resins and alkylcelluloses, or aqueous resins such as maleic acid-based, acrylic acid-based, casein, shellac, and glue can be used.

Further, as a solvent for preparing the ink,
Alcohols such as methanol, ethanol, propanol and butanol, cellosolves such as methyl cellosolve and ethyl cellosolve, aromatics such as benzene, toluene and xylene, esters such as ethyl acetate and butyl acetate, acetone, methyl ethyl ketone and cyclohexanone. Hydrocarbons such as ketones, ligroin, cyclohexane and kerosene, dimethylformamide and the like can be used. When an aqueous resin is used, water or water and a mixture of the above solvents can also be used.

Suitable base materials for applying ink are thin paper such as condenser paper and glassine paper, and films of plastics having good heat resistance such as polyester, polyamide and polyimide. These base materials are heat-sensitive. 5 to 50 in order to improve the heat transfer efficiency from the recording head to the dye
A thickness on the order of micrometers is suitable. The dye carrying layer provided on the surface of the base material can be produced by applying the above-mentioned ink to the base material.

Examples of the recording material 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. Polyester resins such as polyethylene terephthalate and polybutylene terephthalate, polystyrene resins, polyamide resins,
Copolymer resins of olefins such as ethylene and propylene and other vinyl monomers, cellulosic resins such as ionomers, cellulose diacetate and cellulose triacetate, fibers made of polycarbonate, polysulfone, polyimide, woven cloth, film, sheet, molding Things etc. are mentioned. Particularly preferred are woven fabrics, sheets or films made of polyethylene terephthalate.

In transfer recording, plain paper is coated with, or impregnated with, plain paper coated with the resin for the recording medium to which acidic fine particles such as silica gel are added, or a resin film is laminated, By using a special processed paper that has been acetylated, good recording with excellent image stability under high temperature and high humidity can be performed. Also, films of various resins or synthetic papers made from them can be used.

Further, after transfer recording, a polyester film, for example, is hot pressed and laminated on the transfer recording surface, whereby the coloring of the dye can be improved and the storage stability of the recording can be achieved.

[0023]

The yellow dye represented by the general formula (1) of the present invention can control the sublimation transfer amount of the dye by changing the energy applied to the thermal head at the time of thermal transfer. Easy and suitable for full color recording.

Further, since it is stable against heat, light, moisture, chemicals, etc., it is not thermally decomposed during transfer recording, and the preservability of the obtained record is excellent.

Further, since the dye of the present invention has good solubility in an organic solvent and dispersibility in water, it is easy to prepare a uniform solvent or a highly concentrated ink dispersed therein. As a result, it is possible to obtain a recording having a good color density, and it is a dye of practical value.

[0026]

EXAMPLES The present invention will be described in detail below with reference to examples.
In the examples, "part" means "part by weight" and "%" means "% by weight".

Example 1 The method for producing the compound of formula (A) is as follows.

In a mixture of 76 parts of acetic acid and 23 parts of concentrated sulfuric acid, 3-
10 parts of amino-N-iso-butylphthalimide was added, and after cooling, 34 parts of 30% nitrosylsulfuric acid was added dropwise at 0 to 10 ° C. and reacted for 1 hour. Excess nitrosyl sulfuric acid was removed by adding 2 parts of sulfamic acid to obtain a diazo solution. Next, in a mixture of 100 parts of water and 1 part of NaOH, the following formula (4)

[0029]

[Chemical 5] 9 parts of the compound of 1 was added and cooled at 0 to 5 ° C., and then the above diazo solution was added dropwise and reacted for 1 hour. After completion of the reaction, the product was filtered, washed, dried and purified by column chromatography to obtain compound (A). The maximum absorption wavelength (λmax) in toluene of the compound was 420 nm.

[0030]

[Chemical 6](1) Method for preparing ink 3 parts of dye of the above formula (A) Polybutyral resin 4.5 parts Methyl ethyl ketone 46.25 parts Toluene 46.25 parts Using a glass bead, the dye mixture of the above composition was used.
By mixing with a conditioner for about 30 minutes
The ink was prepared. (2) Method of manufacturing transfer sheet Using a gravure proofing machine (plate depth 30 μm), heat-resistant treatment is applied to the back surface.
9 μm thick polyethylene terephthalate powder
The above-mentioned ink is applied to a rum at a dry coating amount of 1.0 g / m. ² In
And then dried. (3) Preparation of recording material Polyester resin 0.8 part (Vylon 103 Toyobo Tg = 47 ° C.) EVA polymer plasticizer 0.2 part (Elvalloy 741p Mitsui Polychemical Tg = 137 ° C.) Amino-modified silicone 0.04 parts (KF-857 manufactured by Shin-Etsu Chemical Co., Ltd.) Epoxy-modified silicone 0.04 parts (KF-103 manufactured by Shin-Etsu Chemical Co., Ltd.) Methyl ethyl ketone / toluene / cyclohexane 9.0 parts (Weight ratio 4: 4: 2) Mix the above Then, prepare a coating liquid and use synthetic paper (Oji Yuka,
Epo FPG 150) with a bar coater (RK Prin)
Manufactured by Coat Instruments, NO.
4.5 g / m when dried using 1)² Apply at the ratio
And dried at 100 ° C. for 15 minutes. (4) Transfer recording The transfer sheet and the recording material are respectively printed with ink.
Transfer by applying the application surface and the application surface of the coating liquid so that they face each other
Thermal head applied voltage from back side of sheet 10V, printing time
Recording is performed under the condition of 4.0 milliseconds and the color density of 2.01 is recorded.
A yellow record was obtained.

The color density is densitometer RD-514 manufactured by Macbeth Co., USA (filter: Ratten N).
O. 58).

The color density was calculated by the following formula.

Color Density = 1og ₁₀ (Io / I) Io = Intensity of Light Reflected from Standard White Reflector I = Intensity of Light Reflected from Test Object In addition, the light resistance test of the obtained recording was carried out by a xenon phosphor. -It was carried out at a black panel temperature of 63 ° C and 2 ° C using a dometer (manufactured by Suga Test Instruments Co., Ltd.), but it was not discolored by irradiation for 40 hours, and the stability of the image under high temperature and high humidity was excellent. .

The fastness of the recorded image obtained is 50 ° C.
After being left in the atmosphere of 48 hours, the image was sharp and the surface was rubbed with white paper, and the color was evaluated.
The sharpness of the image did not change, the white paper was not colored, and the fastness of the recorded image was good. Example 2 The method for producing the compound of formula (C) is as follows.

To a mixture of 76 parts acetic acid and 23 parts concentrated sulfuric acid, 4 parts
10 parts of -amino-N-tert-butylphthalimide were added, and after cooling, 30% nitrosyl sulfuric acid 34 was added at 0 to 10 ° C.
A part was dropped, and the reaction was performed for 1 hour. Excess nitrosyl sulfuric acid was removed by adding 2 parts of sulfamic acid to obtain a diazo solution. Next, in a mixture of 100 parts of water and 1 part of NaOH, the following formula (5)

[0036]

[Chemical 7] 7 parts of the above compound was added and cooled to 0 to 5 ° C., and then the above diazo solution was added dropwise and reacted for 1 hour. After completion of the reaction, the product was filtered, washed and dried to obtain the compound (B).

[0037]

[Chemical 8] Next, 10 parts of the compound (B) was added to 50 parts of DMF and K ₂ C.
The mixture was added to a mixture of 2 parts of O _{3 and} heated to 100 ° C. Three
After stirring for 0 minutes, 5.5 parts of iso-propyl chloroacetate was added dropwise and reacted at the same temperature for 3 hours. After the reaction is completed, 60 ℃
After cooling to 50 parts of water, the precipitated product was filtered, washed, dried and purified by column chromatography to obtain a compound (C).

The maximum absorption wavelength (λmax) in toluene of the compound was 420 nm.

[0039]

[Chemical 9] Ink was prepared, a transfer sheet and a recording material were prepared, and transfer recording was carried out in the same manner as in Example 1 to obtain a yellow recording having a color density of 2.05.

All of these recordings were subjected to the light resistance test by the same method as in Example 1. As a result, the recordings hardly changed and the stability of the image under high temperature and high humidity was excellent.

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

Examples 3 to 26 The yellow dyes shown in Table 1 were produced in the same manner as in Example 1 or 2, and the ink, the transfer sheet, the recording material and the transfer recording were similarly prepared. Done, table 1
Each record shown in was obtained.

A light fastness test was carried out on all of these recordings by the same method as in Example 1. As a result, the recordings showed almost no change and the stability of the image under high temperature and high humidity was excellent. A fastness test was conducted in the same manner as in Example 1,
The sharpness of the image did not change, the white paper was not colored, and the fastness of the recorded image was good.

[0044]

[Table 1]

[0045]

[Table 2]

[0046]

[Table 3]

[0047]

[Table 4]

[0048]

[Table 5] Comparative Examples 1 to 4 In the same manner as in Example 1, the yellow dyes shown in Table 2 were used to prepare an ink, a transfer sheet, a recording material, and transfer recording. Further, a light resistance test and a fastness test were performed in the same manner as in Example 1.

As a result, as shown in Table 2, none satisfying the conditions of maximum transfer density, light resistance and fastness at the same time was obtained, and the image became unclear, and the white paper was markedly colored and defective.

[0050]

[Table 6]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Isamu Goda 3-30 Kasamatsu-dori, Hyogo-ku, Kobe-shi, Hyogo (72) Inventor Hitoshi Koshida Takatsu-ku, Kawasaki-shi, Kanagawa 600-405 (72) Invention Hiroshi Eguchi 1-1-1 Ichigayaka-cho, Shinjuku-ku, Tokyo Inside Dai Nippon Printing Co., Ltd. (72) Inventor Kazuya Yoshida 1-1-1 Ichigayaka-cho, Shinjuku-ku, Tokyo Inside Dai Nippon Printing (72) ) Inventor Ryohei Takiguchi 1-1-1, Tanikaga-cho, Shinjuku-ku, Tokyo Dai Nippon Printing Co., Ltd.

Claims (3)

[Claims] 1. The following general formula (1): [In the formula, R ¹ and R ² are a hydrogen atom, an alkyl group, a cycloalkyl group, an alkoxyalkyl group, a halogenoalkyl group, a cyanoalkyl group, a hydroxyalkyl group, an alkenyl group, an aralkyl group, a substituted or unsubstituted aryl group. , An alkoxycarbonyl group, an alkoxycarbonylalkyl group or an alkoxyalkoxycarbonylalkyl group. ] The dye for thermal transfer recording represented by the following. 2. A thermal transfer recording ink composition comprising a thermal transfer recording dye represented by the general formula (1) according to claim 1, a binder resin, an organic solvent and / or water. object. 3. A transfer comprising a base sheet and a dye-supporting layer formed on one surface of the base sheet, wherein the dye contained in the dye-supporting layer is the dye according to claim 1. Sheet.