JPH05169852A - Dyestuff for thermal transfer recording, ink composition for thermal transfer recording and transfer sheet - Google Patents

Abstract

PURPOSE:To obtain dyestuffs and an ink composition for thermal transfer recording having high sublimating speed and excellent image stability after transfer by using dyestuffs being shown in specific chemical formula and having superior solubility to an ink solvent and the low melting point as the sublimating dyestuffs for thermal transfer recording. CONSTITUTION:In a thermal transfer recording system using sublimating dyestuffs, a transfer sheet, in which condenser paper, a PET film, etc., are coated with sublimating dyestuffs changed into ink, is employed, and the transfer sheet is heated selectively by a thermal head, thus conducting transfer to recording paper. Dyestuffs shown in general formula mentioned on the right are used as the sublimating dyestuffs at that time. In formula, R<1> represents an alkyl sulfonyl group, an alkylamino carbonyl group, etc., R<2>-R<4> a hydrogen atom, 1-4C alkyl groups, etc., R<5>, R<6> the hydrogen atom, the 1-4C alkyl groups, etc., and R<7>, <8> the hydrogen atom, a substituted or non-substituted alkyl group, etc. The dyestuffs are kneaded with a binder resin, an organic solvent, etc., thus acquiring an ink composition for thermal transfer recording.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art A thermal transfer recording method using a sublimation dye uses a thin condenser paper having a thickness of several microns or a transfer sheet coated with a sublimable dye which is made into an ink on a PET film, and is transferred to a thermal head. This is one of the thermal transfer printing methods in which heat is selectively heated and transferred to a recording paper which is a recording material, and is currently used as a means for image recording (hard copy) of various image information.

The sublimation dyes used here are required to have abundant colors and excellent color mixing properties, strong dyeing power and relatively high stability. The above-mentioned recording method has a great feature that other printing methods do not have, in that the amount of dye sublimated depends on heat energy and the dye density after dyeing can be controlled in an analog manner.

In conventional magenta color sublimation dyes,
Very few have both high sublimation speed and image stability after transfer, and it has been expected that dyes satisfying the optimum conditions as sublimation dyes will appear.

[0005]

DISCLOSURE OF THE INVENTION As a result of intensive studies to solve the above problems, the present inventors have generally found that in dyes for thermal transfer recording, the sublimation rate at the time of transfer is the It was found that the action, the interaction between the dye molecule and the binder resin for the ink, is involved.

That is, it is preferable that the sublimation 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 the transfer sheet is manufactured. It became clear that the compound was a good dye, and it was found that the compound represented by the general formula (1) described below can be an excellent magenta type dye for thermal transfer recording, and the present invention has been completed.

Therefore, the object of the present invention is to obtain a high sublimation rate,
Dye for thermal transfer recording, which also has image stability after transfer,
An object is to provide an ink composition for thermal transfer recording and a transfer sheet.

[0008]

In order to solve the above problems, the present invention provides the following general formula (1)

[0009]

[Chemical 2] [In the formula, R ¹ represents an alkylsulfonyl group, an alkoxy group, an alkylaminocarbonyl group, a halogen atom or a cyano group, and R ^{2 to} R ⁴ represent a hydrogen atom, a C _{1 to} C ₄ alkyl group, an alkoxy group, Represents a halogen atom or a cyano group, R ⁵ and R ⁶ represent a hydrogen atom, a C _{1 to} C ₄ alkyl group,
Alkoxy group, alkylcarbonylamino group, alkoxycarbonylamino group, alkylsulfonylamino group,
A formylamino group and a halogen atom are shown, and R ⁷ and R ⁸ are a hydrogen atom, a substituted or unsubstituted alkyl group, an aralkyl group, an alkenyl group and an aryl group. ] The dye for thermal transfer recording represented by
An ink composition for a transfer sheet containing a binder resin and an organic solvent and / or water, and a base sheet and a dye carrying layer formed on one surface of the base sheet, and contained in the dye carrying layer The dye includes a transfer sheet which is the above dye.

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

The present invention will be described in detail below.

The sublimation dye according to the present invention has the above general formula (1).
In the general formula (1), R ¹ is a compound represented by
Alkoxy groups having 1 to 6 carbon atoms such as methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, iso-butoxy, sec-butoxy, tert-butoxy, n-hexyloxy, methylsulfonyl, ethylsulfonyl, n. -C1-C4 such as propylsulfonyl
Alkylsulfonyl group, methylaminocarbonyl, ethylaminocarbonyl, n-propylaminocarbonyl, iso-propylaminocarbonyl, n-butylaminocarbonyl, iso-butylaminocarbonyl, s
ec-butylaminocarbonyl, tert-butylaminocarbonyl, dimethylaminocarbonyl, diethylaminocarbonyl, di-n-propylaminocarbonyl,
An alkylaminocarbonyl group such as di-n-butylaminocarbonyl, a halogen atom such as fluorine, chlorine and bromine, and a cyano group are shown.

Further, in the general formula (1), R ² , R ³ and R ⁴
Are the same or independently of each other, a hydrogen atom, methyl, ethyl, n-propyl, iso-propyl, n-butyl, i
C1-C4 alkyl groups such as so-butyl, sec-butyl, tert-butyl, methoxy, ethoxy, n-
Propoxy, iso-propoxy, n-butoxy, is
It represents an alkoxy group having 1 to 6 carbon atoms such as o-butoxy, sec-butoxy, tert-butoxy, n-hexyloxy, a halogen atom such as fluorine, chlorine and bromine, and a cyano group.

In the general formula (1), R ⁵ and R ⁶ are the same or independently of each other, a hydrogen atom, methyl, ethyl, n.
-Propyl, iso-propyl, n-butyl, iso-
Butyl, sec-butyl, tert-butyl and other alkyl groups having 1 to 4 carbon atoms, methoxy, ethoxy, n-propoxy, iso-propoxy, n-butoxy, iso-butoxy, sec-butoxy, tert-butoxy, n-.
Hexyloxy and other C1-6 alkoxy groups, methylcarbonylamino, ethylcarbonylamino, n-propylcarbonylamino, iso-propylcarbonylamino, n-butylcarbonylamino and other C1-4 carbon atoms.
Alkylcarbonylamino group, methoxycarbonylamino, ethoxycarbonylamino, n-propoxycarbonylamino, iso-propoxycarbonylamino,
C1-C4 alkoxycarbonylamino group such as n-butoxycarbonylamino, formylamino group, methylsulfonylamino, ethylsulfonylaminino, n-propylsulfonylamino, iso-propylsulfonylamino, n-butylsulfonylamino, etc. 1 to 1 carbon atoms
4 represents an alkylsulfonylamino group of 4, a halogen atom such as fluorine, chlorine and bromine.

Further, in the general formula (1), R ⁷ and R ⁸ are the same or independently of each other, a hydrogen atom, methyl, ethyl, n
-Propyl, iso-propyl, n-butyl, iso-
Butyl, sec-butyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl and other alkyl groups having 1 to 8 carbon atoms, allyl, 2-butenyl, 3
-Butenyl, 3-methyl-2-butenyl and the like having 3 to 3 carbon atoms
C6 alkenyl group, benzyl, phenethyl, etc., 7 carbon atoms
10 to 10 aralkyl groups, phenyl, p-tolyl, m-tolyl, o-tolyl, p-chlorophenyl, m-chlorophenyl, 0-chlorophenyl, and other aryl groups having 6 to 10 carbon atoms. Substituted alkyl having the following substituents can also be R ⁷ and R ⁸ . Such substituents include, for example, methoxy, ethoxy, n-propoxy, i
so-propoxy, n-butoxy, iso-butoxy,
sec-butoxy, tert-butoxy, n-hexyloxy alkoxy group having 1 to 6 carbon atoms, alkoxymethoxy group having 1 to 6 carbon atoms such as methoxymethoxy, methoxyethoxy, ethoxyethoxy, methoxypropoxy, ethoxypropoxy and propoxypropoxy, Phenoxy, p-methylphenoxy, m-methylphenoxy, o
-Methylphenoxy, p-chlorophenoxy, m-methylphenoxy, o-methylphenoxy and the like having 6 to 1 carbon atoms
2 aryloxy groups, thiophenoxy, p-methylthiophenoxy, m-methylthiophenoxy, o-methylthiophenoxy and other thioaryloxy groups having 6 to 12 carbon atoms, methylcarbonylamino, ethylcarbonylamino, n-propylcarbonylamino, C1-C4 alkylcarbonylamino groups such as iso-propylcarbonylamino, n-butylcarbonylamino, methoxycarbonylamino, ethoxycarbonylamino, n-propoxycarbonylamino, iso-propoxycarbonylamino, n-butoxycarbonylamino, etc. Carbon number of 1
~ 4 alkoxycarbonylamino group, formamino group, methylcarbonyl, ethylcarbonyl, n-propylcarbonyl, iso-propylcarbonyl, n-butylcarbonyl and other alkylcarbonyl groups having 1 to 4 carbon atoms, methoxycarbonyl, ethoxycarbonyl, n-propoxycarbonyl, iso-propoxycarbonyl,
an alkoxycarbonyl group having 1 to 4 carbon atoms such as n-butoxycarbonyl, methylcarboxy, ethylcarboxy,
C1-C4 alkylcarboxy groups such as n-propylcarboxy, iso-propylcarboxy and n-butylcarboxy, carbon numbers such as methoxycarboxy, ethoxycarboxy, n-propoxycarboxy, iso-propoxycarboxy and n-butoxycarboxy. 1 to 4 alkoxycarboxy groups, methoxycarbonylmethoxy, ethoxycarbonylethoxy, n-propoxycarbonylmethoxy, iso-propoxycarbonylmethoxy, n-butoxycarbonylmethoxy and the like having 1 to 4 carbon atoms.
Alkoxycarbonylalkoxy group of, fluorine, chlorine,
Examples thereof include a halogen atom such as bromine, a cyano group and the like.

The sublimation dye represented by the general formula (1) according to the present invention is subjected to a conventional method, for example, by diazo coupling a substituted aniline represented by the following reaction formula, and then cyanating the bromine at the ortho position of the azo group. Can be obtained by doing.

[0017]

[Chemical 3] In the present invention, it is also possible to produce an ink composition for thermal transfer recording using the dye produced by the above method and supply it in the form of ink.

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

As the thermal transfer method, the ink composition obtained as described above is applied onto a suitable base material sheet to prepare a transfer sheet, and the sheet is superposed on a recording material.
Next, a method of heating and pressurizing with a thermal recording head from the back surface of the sheet can be exemplified, and in this case, the dye on the sheet is transferred onto the recording material.

The transfer sheet of the present invention is characterized by using the specific dye as described above, and other constitutions may be the same as those of the conventionally known transfer sheet.

The substrate sheet used in the transfer sheet of the present invention containing the above-mentioned dye may be any conventionally known one having a certain degree of heat resistance and strength,
For example, 0.5 to 50 μm, preferably 3 to 10 μm
m thick paper, various processed papers, polyester film, polystyrene film, polypropylene film,
A polysulfone film, a polycarbonate film, an aramid film, a polyvinyl alcohol film, cellophane, etc., and a polyester film is particularly preferable.

The dye carrying layer provided on the surface of the substrate sheet as described above is a layer in which the dye represented by the general formula (1) is carried by an optional binder resin.

As the binder resin for supporting the above-mentioned dye, any conventionally known binder resin can be used. Preferred examples include ethyl cellulose, hydroxyethyl cellulose, ethyl hydroxy cellulose, hydroxypropyl cellulose, methyl cellulose and cellulose acetate. Cellulose resins such as cellulose acetate butyrate, polyvinyl alcohol, polyvinyl acetate, polyvinyl butyral, polyvinyl acetoacetal, polyvinyl pyrrolidone, vinyl resins such as polyacrylamide, and the like. Among them, polyvinyl butyral and polyvinyl acetal are particularly preferable. It is preferable in terms of heat resistance, dye transferability, and the like.

The dye-carrying layer of the transfer sheet of the present invention is basically formed of the above-mentioned materials, but may also contain various conventionally known additives if necessary.

Such a dye-supporting layer is preferably prepared by adding the above-mentioned dye, binder resin and other optional components to a suitable solvent to dissolve or disperse each component to prepare a support-layer forming ink composition, This is applied and dried on the above-mentioned substrate sheet to form.

The supporting layer thus formed has a thickness of about 0.2 to 5.0 μm, preferably 0.4 to 2.0 μm, and the above-mentioned dye in the supporting layer is the weight of the supporting layer. It is preferably present in an amount of 5 to 70% by weight, preferably 10 to 60% by weight. The transfer sheet of the present invention as described above is sufficiently useful as it is for thermal transfer, but an anti-sticking layer, that is, a release layer may be further provided on the surface of the dye-carrying layer, and such a layer is provided. This makes it possible to prevent the transfer sheet and the recording material from sticking to each other during thermal transfer, use an even higher thermal transfer temperature, and form an image with a more excellent density.

As the release layer, even if only the adhesion-preventing inorganic powder is simply adhered, a considerable effect is exhibited.
Further, for example, a resin having excellent releasability such as a silicone polymer, an acrylic polymer or a fluorinated polymer can be used.
It can be formed by providing a release layer of 01 to 5 μm, preferably 0.05 to 2 μm.

The inorganic powder or releasable polymer as described above exhibits a sufficient effect even when incorporated in the dye carrying layer.

Further, a heat-resistant layer may be provided on the back surface of such a transfer sheet in order to prevent adverse effects due to the heat of the thermal head.

The recording material used for forming an image by using the above-mentioned transfer sheet may be any material as long as its recording surface has a dye receptivity to the above dyes, or In the case of paper, metal, glass, synthetic resin or the like having no dye receiving property, the dye receiving layer may be formed on at least one surface thereof.

Any conventionally known applying means can be used as the applying means of the thermal energy used when performing thermal transfer using the transfer sheet of the present invention as described above and the recording material as described above. For example, a thermal printer (for example,
By using a recording device such as Hitachi, Ltd., video printer VY-100) and the like, by controlling the recording time, it is possible to apply heat energy of about 5 to 100 mJ / mm ³ , which is sufficient for the intended purpose. Can be achieved.

[0032]

INDUSTRIAL APPLICABILITY The magenta sublimation dye represented by the general formula (1) of the present invention can control the sublimation transfer amount of the dye by changing the thermal transfer time and the energy applied to the thermal head. 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 obtained record is excellent in storability.

Further, since the dye of the present invention has good solubility in organic solvents and dispersibility in water, it is easy to prepare a highly concentrated ink that is uniformly dissolved or decomposed, and as a result, the color density is increased. It is a dye that is practically valuable because it can obtain good recording quality.

[0035]

EXAMPLES The present invention will be specifically described below with reference to examples. Parts in the examples indicate parts by weight. % Means% by weight. Example 1 A compound represented by the following formula (A) was synthesized by a conventional method.

[0036]

[Chemical 4] Further, using the compound of the following formula (A), an ink composition was prepared, a transfer sheet and a recording material were prepared and transfer recording was carried out as follows.

The maximum absorption wavelength (λmax) of the compound in chloroform was 525 nm. (1) Method for preparing ink composition Dye of the above formula (A) 3 parts Polybutyral resin 4.5 parts Methyl ethyl ketone 46.25 parts Toluene 46.25 parts Dye mixture having the above composition is used in a paint conditioner using glass beads. The ink was prepared by mixing for about 30 minutes. (2) Method for producing transfer sheet Using a gravure proofing machine (plate depth 30 μm), a 9 μm-thick polyethylene terephthalate film having a heat-treated back surface was coated with the above ink so that the dry coating amount was 1.0 g / m ^2. 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 (Elveiro 741p manufactured by Mitsui Polychemical; Tg =
-37 ° C) Amino-modified silicone 0.04 part (KF-857 manufactured by 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 are mixed to prepare a coating solution, and synthetic paper (manufactured by Oji Yuka,
Bar coater (RK Print) on YUPO FPG # 150
Manufactured by Coat Instruments, No.
1) was applied at a rate of 4.5 g / m ² when dried, and dried at 100 ° C. for 15 minutes. (4) Transfer recording The transfer sheet and the recording material are superposed with the ink application surface and the coating liquid application surface facing each other, and the thermal head applied voltage of 10 V and the printing time from the back surface of the thermal transfer sheet. Recording was carried out under the condition of 0 milliseconds to obtain a magenta color recording having a color density of 2.00.

The color density is densitometer RD-514 manufactured by Macbeth Co. (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 fastness test of the obtained recording was xenon faded. It was carried out at a black panel temperature of 63 ± 2 ° C. using a meter (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.

Further, the fastness of the obtained recorded image is 50 ° C.
After being left for 48 hours in the atmosphere, 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 A compound represented by the following formula (B) was synthesized by a conventional method.
Absorption maximum wavelength (λma) of this compound in toluene
x) was 515 nm.

[0042]

[Chemical 5] 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 magenta color recording having a color density of 2.00.

A light fastness test was conducted on all of these recordings 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 carried out 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 20 Magenta dyes shown in Table 1 were produced in the same manner as in Example 1, and ink was similarly prepared and transfer sheets were prepared in the same manner.
A recording material was produced and transfer recording was performed, and each recording shown in Table 1 was obtained.

A light fastness test was conducted on all of these recordings 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 carried out 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.

[0047]

[Table 1]

[0048]

[Table 2]

[0049]

[Table 3]

[0050]

[Table 4]

[0051]

[Table 5] The judgment results of light resistance and fastness are shown by O for good and X for bad. Comparative Examples 1 to 4 In the same manner as in Example 1, the compounds shown in Table 2 were subjected to ink preparation, transfer sheet preparation, recording material preparation, and transfer recording. Further, a light resistance test and a fastness test were performed in the same manner as in Example 1. The results are also shown in Table 2. The judgment results are shown as in Table 1.

[0052]

[Table 6]

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hitoshi Koshida 12-5-510 Koshienguchi Kitamachi, Nishinomiya-shi, Hyogo (72) Inventor Keisuke Soma 300 Hirahara-cho, Omuta-shi, Fukuoka (72) Ryohei Takiguchi Shinjuku, Tokyo 1-1-1, Ichiya-Kagacho, Ichi-ku, Dai Nippon Printing Co., Ltd. (72) Inventor, Hiroshi Eguchi 1-1-1, Ichiya-Kagacho, Shinjuku-ku, Tokyo Dai Nippon Printing Co., Ltd. (72) Inventor, Kimiaki Kafuku Tokyo 1-1-1 Ichigaya-Kagacho, Shinjuku-ku, Tokyo Inside Dai Nippon Printing Co., Ltd.

Claims (3)

[Claims] 1. The following general formula (1): [In the formula, R ¹ represents an alkylsulfonyl group, an alkoxy group, an alkylaminocarbonyl group, a halogen atom or a cyano group, and R ^{2 to} R ⁴ represent a hydrogen atom, a C _{1 to} C ₄ alkyl group, an alkoxy group, Represents a halogen atom or a cyano group, R ⁵ and R ⁶ represent a hydrogen atom, a C _{1 to} C ₄ alkyl group,
Alkoxy group, alkylcarbonylamino group, alkoxycarbonylamino group, alkylsulfonylamino group,
A formylamino group and a halogen atom are shown, and R ⁷ and R ⁸ are a hydrogen atom, a substituted or unsubstituted alkyl group, an aralkyl group, an alkenyl group and an aryl group. ] The dye for thermal transfer recording shown by. 2. An ink composition for heat-sensitive transfer recording comprising a dye for heat-sensitive transfer recording represented by the general formula (1) according to claim 1, a binder resin and 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.