JPS61227093A - Coloring matter of anthraquinone series for thermal transfer recording - Google Patents

Abstract

PURPOSE:To obtain a transfer sheet having sperior wear and fastness properties on which a coloring matter is uniformly applied in a high density, by a method wherein a color of magenta is constituted by the specified coloring matter of the anthraquinone series. CONSTITUTION:The coloring matter for thermal transfer recording is constituted by the coloring matter of the anthraquinone series shown by a general formula (I). The coloring matter of the anthraquinone series is produced by a method wherein a compound shown by a general formula (II) and a compound of the phenol group shown by a general formula (III) are heated with a deoxidizer in a polar solvent. The ink, which prepared by a method in which the coloring matter is taken into solution in the medium together with a binding agent, is applied on a base film and dried to produce a transfer sheet.

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention A) Field of Industrial Application The present invention relates to a dye used in sublimation type thermal transfer recording.

Conventional technology There has been a demand for facsimile printers, copiers, and technology to record television images in color, and electrophotography,
Color recording technologies using inkjet, thermal transfer, etc. are being considered.

The thermal transfer recording method is considered to be advantageous over other methods because the device is easy to maintain and operate, and the device and consumables are inexpensive.

Thermal transfer methods include a melting method in which a transfer sheet with a heat-melting ink layer formed on a base film is heated by a heat-sensitive head to melt the ink and transfer recording onto a recording medium; There is a sublimation method in which a transfer sheet on which an ink layer containing a sublimable dye is formed is heated by a thermal head to sublimate the dye and transfer and record onto the recording medium. Since the amount of sublimation transfer of the dye can be controlled by changing the energy applied, gradation recording becomes easier, and this is considered to be particularly advantageous for full-color recording.

C) Problems to be Solved by the Invention The transfer sheet used for the above purpose is required to be capable of uniform transfer recording with high density and to have good abrasion resistance. In other words, if the image is not transferred uniformly, density unevenness will occur in the image, and if the abrasion resistance is poor, excess dye will develop in areas other than the image area that are not recorded, resulting in the so-called background smearing phenomenon. This is because the overall quality will deteriorate.

These scumming phenomena occur because the dye recrystallizes when it is dissolved or dried, forming coarse crystals, or because the dye does not dissolve completely and remains as coarse crystals. it is conceivable that.

Structure of the Invention A) Means for Solving the Problems Namely, the present invention is based on the following general formula CI] OH (wherein R is a C1-C1° alkyl group, a C3-C1° alkoxy group, The gist thereof is an anthraquinone dye for thermal transfer recording, which is represented by a fluoromethyl group.

The method for producing these anth-2-quinone dyes of the present invention includes, for example, a compound represented by the following structural formula (Il) and a phenol represented by the following general formula [I] (wherein R is the same as defined above). (K) can be obtained by heating the compounds in a polar solvent in the presence of a deoxidizing agent.

Particularly preferred are dyes in which 8 in the general formula CI) is C3-C, an alkyl group, or a C1-C6 alkoxy group.

When applying the dye of the present invention to this recording method, it is necessary to prepare an ink by dissolving the dye together with a binder in a medium, apply the ink onto a base film, and dry it to prepare a transfer sheet. .

Binders for ink preparation include water-soluble resins such as cellulose, acrylic acid, and starch, and organic solvent-soluble resins such as acrylic resin, methacrylic resin, polystyrene, polycarbonate, polysulfone, polyethersulfone, and ethyl cellulose. Examples include resin.

Media for ink preparation include aromatics such as toluene, xylene, and chlorobenzene, esters such as ethyl acetate and butyl acetate, ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone, methylene chloride, chloroform, and trichloroethylene. chlorinated solvents such as tetrahydrofuran, ethers such as dioxane, N,N-dimethylformamide,
Organic solvents such as N-methylpyrrolidone may be mentioned.

Suitable base films for applying ink for making transfer sheets include condenser paper, thin paper such as glassine paper, and plastic films with good heat resistance such as polyester, polyamide, and polyimide.
Their thickness can range from 3 to SO μm.

As a method of applying ink to the base film,
It can be carried out using a bath roll coater, Clavier coater, rod coater, air doctor coater, etc., and the thickness of the ink coating layer after drying is o, i'-zμ.
It is sufficient to apply the coating within the range of m ("Coating Method" by Yuji Harasaki, published by Maki Shoten in 1979).

Functions and Effects of the Invention The anthraquinone dye represented by the above CI of the present invention can be used to produce full-color recording with good color reproducibility by combining it with a bright magenta color, appropriate yellow color, and cyan color. suitable for obtaining. In particular, heat, light,
Since it is stable against moisture and chemicals, it does not undergo thermal decomposition during transfer recording, and the resulting recording has excellent storage stability. In addition, since the dye of the present invention has particularly good solubility in organic solvents and binders, it is easy to prepare uniformly dissolved and highly concentrated inks, and these inks can be used. By doing so, it is possible to obtain a transfer sheet having excellent abrasion resistance and fastness to which the dye is applied uniformly and at a high concentration. Therefore, by using these transfer sheets, it is possible to obtain excellent recording without image unevenness and background smear.

EXAMPLES The present invention will be specifically explained with reference to Examples below, but these Examples are not intended to limit the present invention.

Example 1 &) Preparation of ink Anthraquinone dye used in this example: The above dye
10f Cellulose acetate (manufactured by Daicel Chemical Co., Ltd., I, -, 7o) / 0) Methyl ethyl ketone toy - A mixture of the above composition was treated with a paint conditioner for 10 minutes to prepare an ink. Pigments and resins are completely dissolved,
It was possible to obtain an ink with a uniform solution.

b) Preparation of transfer sheet The above ink was coated with a bar coater (RK Pr1ntC+a
After coating on a capacitor paper (lθ μm thickness) using a tfstramInts A/), the transfer sheet was air-dried to obtain a transfer sheet. The resulting transfer sheet was uniform and had excellent abrasion resistance.

e) Transfer recording The ink-applied surface of the above transfer sheet was placed on the recording medium and recorded using a thermal head under the following conditions, and a high-definition image was recorded in a clear magenta color.
It was possible to obtain a good transfer record with a color density of s without image unevenness and with no background stains.

Recording conditions Linear density of main scanning and sub-scanning: DADRA)/g Recording voltage
Power: 0.4 W/dot head heating time: 10 m-・C The recording medium was an aqueous dispersion of saturated polyester 3% by weight (manufactured by Toyobo Co., Ltd., Vyloner/I/MD-
tco00. Product name) toy and silica (Nlpm11 E--OA, manufactured by Nippon Silikani Gyo Co., Ltd., product name)/)
The prepared liquid was coated on high-quality paper (0 μm thick) using a Percoater (RK Pr1nt Coat Instr.
It was manufactured by applying and drying the coating using AJ).

Color density was measured using a densitometer RD manufactured by Macbeth, USA.
-! /' Measured using type I (filter m: Utten Arg).

A light resistance test of the obtained record was carried out using a carbon arc fade meter (manufactured by Suga Test Instruments Co., Ltd.) (black panel temperature 6J ± ℃), but after irradiation for eO hours, the color changed and faded. There wasn't. Furthermore, the transfer sheet and recording were stable against heat and moisture, and had excellent storage stability in the dark.

Examples! Examples! Instead of the dyes used in Table 1, the dyes shown in Table 1 were used to prepare ink, prepare a transfer sheet, and perform transfer recording in the same manner as in Example 1. As a result, the color densities and sharpness shown in Table 1 were obtained. It was possible to obtain a good transfer record with no uneven magenta image and no background stains.

The results of the light fastness test of the obtained record and the dark storage stability test of the transfer sheet and record were good.

Example 3 Dye (same as Example 1) IO? Ethyl cellulose (manufactured by Bercules) IO? Methyl ethyl ketone Z0? Total
The transfer sheet was prepared and the transfer recording was performed in the same manner as in Example 1, except that the ink was prepared at 100 f.
Clear and even magenta image with 150 color density,
Good transfer records with no background stains could be obtained.

The results of the light fastness test of the obtained recording and the dark storage stability test of the transfer sheet recording were good.

Comparative Example 1 An ink was prepared in the same manner as in Example 1 using a dye represented by the following structural formula % in place of the anthraquinone dye of the present invention used in Example 1. The dye was not completely dissolved, and some of the dye remained as coarse crystals.

When the above ink was applied in the same manner as in Example 1, recrystallization also occurred during drying, resulting in an uneven transfer sheet with coarse crystals deposited here and there.

When transfer recording was performed using the above transfer sheet in the same manner as in Example 1, an uneven transfer record with uneven images was obtained, and moreover, excess dye was colored even in the unrecorded areas. occurred, reducing the overall quality of the image.

Applicant: Mitsubishi Chemical Industries, Ltd. Agent: Patent Attorney Hase - (1 other person)

Claims (1)

[Claims] (1) General formula [I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼[I] (In the formula, R is an alkyl group of C_2 to C_1_0, C_2
~ C_1_0 represents an alkoxy group or a trifluoromethyl group) An anthraquinone dye for thermal transfer recording.