JPS6083890A - Preparation of thermal transfer recording medium - Google Patents

Abstract

PURPOSE:To obtain a thin color material layer having a constant film thickness, in providing a color material layer onto a support by a solvent coating method, by coating a coating solution prepared by dissolving or dispersing a colorant, a resin and a specific heat meltable substance in a solvent before removing said solvent. CONSTITUTION:A coating solution prepared by dissolving or dispersing a colorant, a resin (pref., one dissolved in a solvent in an amount of 1g or more in 100g of the solvent at 40 deg.C, e.g., gelatine) and a heat meltable substance not dissolved in a solvent in an amount of 5g or more, pref., 3g or more at 40 deg.C (pref., plant wax such as carnauba wax) in a solvent (e.g., n-hexane) is applied to a support by a solvent coating method and said solvent is removed to obtain the objective thermal transfer recording medium.

Description

[Detailed description of the invention] [Technical field] The present invention relates to a method for manufacturing a thermal transfer-I7 recording medium.

More specifically, the present invention relates to a method for manufacturing a heat-sensitive transfer recording medium that can produce a heat-sensitive transfer recording medium having a coloring material layer of a certain quality.

Conventional technology] Thermal transfer recording media have traditionally been used with thermal printers, thermal facsimiles, etc. Recording sheet like paper 1
−． It is used as a recorder S7 for transferring and forming an image on the 1-. This thermal transfer recording medium has at least one coloring material layer on the support. A layer containing a chemical substance is known. Also,
As the support, in order to obtain good reproducibility of the dye transfer image obtained from the color material layer provided in this paper, a film or the like having excellent surface smoothness and dimensional stability is used. It is being

Thermal transfer recording media have such surface smoothness and (j,
J′ Legal Qualitative On an excellent support, the hon!・Manufactured by applying a color material layer using the melt method or coating method. Among these, the present invention is a technology belonging to the Turpen 1 method.

The technique of applying a coloring material layer by solvent coating generally has the problem that (a) it is difficult to form a stable coloring material layer with a constant thickness. For example, 4. v open 1q3
58 128897 No. QfJ L: Ha, Wi Y: Wax that dissolves 10% by weight or more (heat-melting material 7+
Is there a technique disclosed for applying a color material layer at a temperature using
Because the viscosity of the coating is sensitive to changes in temperature, and the viscosity of the coating solution is very low, there are limitations to the IJ coating method and it is extremely difficult to control the coating film. A drawback is that it is difficult to obtain a thermal transfer recording medium having a coloring material layer of constant quality. Therefore, with this technique, a lot of cost and labor is required for coating management, such as controlling the skin temperature during coating and controlling the coating rli speed.

[Object of the invention] The uninvented object is that the viscosity of the coating 4i liquid during coating is not easily affected by environmental temperature changes, that the coating speed can be easily controlled, and that stable quality can be achieved with a constant film thickness. The object of the present invention is to clarify a method for producing a heat-sensitive transfer recording medium that can provide a heat-sensitive transfer recording medium having a coloring material layer.

Other objects of the invention will become apparent from the following description of the specification.

[Summary of the Invention] As a result of intensive research, the comparative inventors have developed a method for producing a thermal transfer recording medium in which a hue layer is coated on a support I by the Zurgento coating method, in which 13 colorants, a resin, and By dissolving or dispersing at least 5 g of a heat-fusible substance that does not dissolve at 40°C in 100 g of a solvent in a solvent, the coating solution is applied to a support, and then the solvent is removed. The inventors have discovered that the above objectives can be achieved, and have arrived at the present invention.

[Structure of the invention] The present invention will be explained in more detail below.

The coating liquid used in the present invention contains at least 1 part each of a colorant, a resin, and an uninvented heat-melting substance! , li are dissolved in a solvent.

The resin of the present invention is preferably a resin that can dissolve 1 g or more in 100 g of solvent at 40°C.

As the uninvented resin, either a hydrophilic polymer or a hydrophobic polymer can be used. Typical hydrophilic polymers are transparent or translucent woody colloids; for example, gelatin, seratin derivatives, cellulose derivatives, proteins such as casein, natural products such as polysaccharides such as starch, natural products, pq-forms, etc. , polyvinyl alcohol, polyhinylpyrroli], acrylamide polymers, etc.;
Vinyl and polyurethane polymer latte.

An example of this is Kusu. The hydrophobic polymer is preferably transparent, and US Pat. No. 3,142,586, 3.
143.38 [No. 1, No. 3,082,674, No. 3,
No. 220,844, No. 3.287,289, No. 3, 4
11,911 may be mentioned as an example. Preferred polyamides include polyvinyl butyral, polyacrylamide I, cellulose acetate butyrate, cellulose acetate phthalate, ethylcellulose, cellulose acetate, polyhinylpyrrolidone, polystyrene, polyvinyl acetate, j! Hinyl chloride-acid-resistant vinyl copolymer, vinyl chloride-vinyl acetate-
Examples include maleic acid terpolymer, tex) phosphorus, sodium alginate, polymethyl mecrylate-1, polyisobutylene, and the like.

In the present invention, one or two of these resins may be inserted.
used in combination, especially Ig in 100 g of solvent at 40 °C.
Below-1, it is preferable to insert one type or two of the dissolving substances and use them in combination.

) F,, the thermofusible substance of the invention is added to 100 g of solvent at 40°C.
It is a substance that does not dissolve in more than 5g, and furthermore,
It is preferable to use a substance that does not dissolve in an amount of 3 g or more.

Examples of the heat-melting substance of the present invention include carnauba wax,
Vegetable waxes such as wood wax, auriculie wax, Nispar wax, animal waxes such as beeswax, insect wax, shellac wax, spermaceti wax, petroleum waxes such as paraffin wax, microcrystalline wax, ester wax, oxidized wax,
In addition to one lasses such as mineral waxes such as monk wax, osikerite, and ceresin; higher fatty acids such as palmitic acid, stearic acid, margaric acid, and behenyl alcohol; palmityl alcohol, stearyl alcohol, behenyl alcohol,
Higher alcohols such as marganyl alcohol, myricyl alcohol, and eicosanol; higher fatty acid esters such as cetyl palmitate, myricyl palmitate, cetyl stearate, and myricyl stearate; acetamide I, propionic acid amide, palmitic acid amide, stearic acid amide , amides such as amide wax; estercam,
Rosin derivatives such as rosin maleic Mm fat, rosin phenol resin, and hydrogenated rosin: Softening point 5 of phenol resin, terpene resin, cyclopentadiene resin, aromatic resin, etc.
Polymer compounds with a temperature of 0 to 120°C; higher amines such as stearylamine, behenylamine, and palmitinamine; polyethylene glycol 4000, polyethylene glycol 6000°t, polyethylene oxy-1, etc., which have C1 independently It may be used or used in combination.

Among these, there are 4 oil waxes, animal waxes, petroleum waxes, mineral wax lamps, and rosin derivatives.
It's so scary. In the present invention, one or a combination of two of these heat-melting substances that do not dissolve 5 g or more in 100 g of solvent at 40'C can be used.

Said solubility in the resins and hot-melt materials of the invention is 16 when dispersed in a solvent at 40° C. for several thousand minutes with conventional stirring, for example in a Homo7 Nizer or Santomill.

In the present invention, when two or more heat-melting substances are used, it is not necessary for both heat-melting substances to satisfy the solubility of the present invention at the same time, and one of the heat-melting substances used in combination is It is sufficient if the solubility conditions of the invention are satisfied.

The coating liquid used in the invention contains at least one colorant. As the coloring agent, various dyes or dyes commonly used in the art can be used without any particular restrictions. For example, a substance that can be dissolved or dissolved when melted in the binder resin in the colorant layer, has a color, and is solid or semi-solid at room temperature is used as a colorant, Various pigments known in the art can be used. Specific examples include the following. Namely, as value color pigments, Kayalon Polyester La IN Yellow 5G-3 (Nikki Kayaku); Oil Yellow 5-7 (white clay), Eisenspiron GRH Special (Hodogaya), Sumiplast Yellow FG ((Igtomo)), Eisenspiron Yellow GRH (Ho (Tani)), etc. are preferably used.As the red pigment is diaceteri 1
Nhuas (・Rent R (Mitsubishi Kasei), Thai Ninx Brilliant BS-E (Mitsubishi Kasei), Sumipurasu Trend H,), Sumipura Stretch Jin Polyester Pink RCL-E ([Ippon Kayaku), ISense Pironlend GEH Special ((lol 11′?
), etc. are preferably used. Blue pigments include Diaceritone Fast Brilliant Blue (-Ryo Kasei), Dianinx Blue EB-E (Ryo Kasei), Kayalon Polyester Blue B-SF Conch (11bon Kayaku), Sumiplast Blue: 3R (Sennin), Sumiplast Blue G (Sennin), etc. are used appropriately. In addition, yellow pigments such as Nza Yellow G (3) and Taldrazine Lake are used, and red face pigments include Brilliant Carmine FB Pure (Nanyo Pigment), Brilliant Carmine 6B (Nanyo Pigment), and Alizarin Lake. Cerulean Blue, Sumikaplinton Anine Blue GN-0 ((l friend), Phthalocyanine Blue, etc.) are used as blue pigments, and carphone blank, oil blank, etc. are used as black pigments. In addition, metal particles or metal oxides may be used.

The coating liquid used in the invention may contain various additives in addition to the above-mentioned components. For example, thermally conductive substances can be added. For example, aluminum, 2 ton 4,
Examples include metals with good thermal conductivity such as zinc. Such a thermally conductive substance promotes the heat conduction effect of melting, softening, or sublimating the coloring material layer by heat. Also, as a fabric softener, 4 types such as castor, linseed oil, and olive oil are
H11 oils, animal oils such as whale oil, and mineral oils may be suitably used.

These resins, heat-melting substances, and colorants are blended in amounts of 0.5 to 30 parts, 40 to 90 parts, and 2 to 25 parts, respectively, per 100 parts (parts by weight, same hereinafter) of the total amount of the heat-melting coloring material layer. It is preferable to use a ratio, and in that case, the melt transferability of the formed heat-melting coloring material layer is very good (If).

Each component of the present invention is dissolved or dispersed in a solvent and coated)1j
It is considered a prefecture.

Examples of the solvent used in the present invention include n-hexane,
Paraffin solvents such as ligroin and isoparaffin, ketone solvents such as acetone, methyl ethyl ketone, and methyl isobutyl ketone, alcohol solvents such as methanol, ethanol, propatool, butanol, water, ester solvents such as ethyl acetate, DMF, DMSO Preferably, ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, alcohol solvents such as methanol, ethanol, propatool, butanol, and ester solvents such as ethyl acetate can be mentioned. Examples include solvents, and mixed solvents thereof may also be used.

The uninvented solvent is one that satisfies the solubility of the present invention for resins and thermofusible substances.

Coating methods suitable for applying a solvent coating of a colorant layer coating solution onto a support are known in the art.
These techniques can also be used in the present invention. For example, the coating liquid of the present invention can be applied by a reverse roll coater method, an extrusion coater method, a graphia coater method, a wire coater method, etc.
Publicly known, 0. A color material layer of 15 JL or less can be applied by solvent coating using the technique described above and then removing the solvent.

The support used in the present invention may be any known support. Further, the thermal transfer recording medium of the present invention has at least one coloring material layer according to the present invention (11), and also has other constituent layers such as a subbing layer, a middle layer, or a second coating layer. You can leave it there. That is, for example, examples of the undercoat layer include silicone resin, melamine resin, polyvinacetal resin, polyethylene, polyvinyl chloride, polyvinylidene chloride, fluororesin, etc. '441 of the undercoat layer is a color material layer. This can be done prior to application.

[Effects of the Invention] According to the present invention, the colorant, the resin, and the solvent 100g contain 4
A coating solution prepared by dissolving or dispersing a heat-fusible substance that does not dissolve in excess of 5g at 0°C in a solvent is used as a support.
Since the solvent is then removed, the purpose of irradiation can be achieved, and in particular, the film thickness can be easily controlled, making it possible to stably obtain the desired thin coloring material layer. .

[Example] Examples are given below, but the embodiments of the present invention are not limited thereto.

Example 1 100 Ill of 2-Proper Tool, 20 g of a heat-fusible substance insoluble to the 2-Proper Tool (10 g of Micro Wax 155 manufactured by Yotsubon Seirosha, 10 g of Hoechst Wax F manufactured by Hoechst), 2- For 100 g of Propatool, at 40°C, a mixture of 2 g of soluble resin (acrylic resin Tesroid 931 manufactured by Tokushima Seisei) was dissolved and dispersed for 1 hour in a water-cooled homogenizer to form a milky white dispersion (S). I love it.

On the other hand, a carbon blank (manufactured by Columbia Carbon Co., Ltd. R
A VE N 1250) 30 g, the Tesroid 9
A mixture of 3 g of 31 and 100 mM of 2-propatool was dissolved and dispersed in a Saresen mill for 7 hours to obtain a dispersion.

The above dispersion liquid (119ml) and 30ml of the dispersion liquid (1) were combined and further diluted with 2-propertool to create a coating liquid (2) with a solid content of 10'J.The temperature of this coating liquid (2) When the viscosity change was measured, as shown in FIG. 1, the viscosity change around room temperature was small.

Kono coating in liquid ■ at 10°C125°C140'0 (7)
A coloring material layer of 2.8 pots in thickness after drying was provided by coating with a wire paper onto a polyethylene terephthalate film support with a thickness of 5.4 pL each, and three types of thermal transfer recording were made. A media sample was prepared.

When the surface of each sample coated with the coloring material layer was observed using a 10x Lux R, it was found that the surface condition was the same regardless of the temperature change during coating.

Thermal printer (prototype model equipped with a 1.7 mm thin 11-inch line thermal held with a heating element of 8 degrees)
When transfer printing was performed on plain paper using , transfer prints of the same quality were obtained for each sample.

Example 2 100 m of ethyl acetate and 25 g of a heat-fusible substance insoluble in the ethyl acetate (1'l microwafer manufactured by Kiseiro Co., Ltd.).

155 or 12.5E, Hoechst Wax F or +2.5g) and 4 to 100g of ethyl acetate.
1g or more at 0℃1. Dissolved polyethylene-ethyl acrylate-1 unit composite (11 units manufactured by Unicar Co., Ltd.)
070), 3g of carbon blank (RA V E N 1250, manufactured by Colombia Carphone Co., Ltd.), ftg, and a mixture of 2E1 and 2E1 were dissolved and dispersed in a ball mill to create a coating solution! -0 The viscosity change with respect to temperature of this coating liquid (1) was measured.As shown in FIG. 2, the viscosity change around room temperature was small.

This coating liquid ■ was applied to a polyethylene terephthalate film support with a thickness of 5.4 pL at each temperature of 25°C and 140°C using a wire paring tool, and the color after drying was 2.8 pL. A material layer was provided to prepare three types of thermal transfer recording medium samples.

When the surface of each sample coated with the coloring material layer was observed using a magnifying glass of 10 times magnification, no difference was observed in the surface condition regardless of the temperature change during coating.

As in Example 1, transfer recording was performed on passing paper using a thermal printer, and no difference in quality of transfer printing was observed for each sample.

Comparative Example 1 A coating liquid (β) was obtained in the same manner as in Example 1 except that xylene was used instead of ethyl acetate. In addition, 40°C
The dissolution performance per 100 g of xylene in Microwax 155 was 20 g or more, and Hoechst Wax F
was 6g.

When the viscosity change of this coating liquid (1) was measured with respect to temperature, as shown in FIG. 3, it changed significantly between 10 and 40°C. Furthermore, when the temperature was increased, the viscosity value was different from that when the temperature was decreased.

Next, this coating solution (2) was applied with a wire sprayer at each temperature of 10°C, 125°C, and 140°C onto a polyethylene terephthalate film support with a thickness of 5.41L, so that the thickness after drying was 2.8°C. A material layer was provided to prepare three types of thermal transfer recording medium samples.

When we observed the surface of each sample coated with the coloring material layer using a 10x magnifying glass, we found that there was a strong dependence on temperature changes during coating, and even at the same temperature, the coating clearly changed when the temperature was rising and when it was falling. Differences were observed in the appearance of the coating, and there were even areas where uneven coating was observed. Furthermore, when transfer recording was carried out on liquid paper using a thermal printer in the same manner as in Example 1, differences in print density, resolution, etc. were observed, and the influence of temperature during coating was strongly recognized.

[Brief explanation of drawings]

FIGS. 1 and 2 are graphs showing the relationship between coating liquid temperature and coating liquid viscosity in a thermal transfer recording medium of the present invention, respectively, and FIG. 3 is a graph showing the relationship between coating liquid temperature and coating liquid in a thermal transfer recording medium of a comparative example. It is a graph showing the relationship with viscosity. Patent applicant Roku Konishi Photo Industry Co., Ltd. Agent Patent attorney Nobuaki Sakaguchi (and one other person) Figure 1 Figure 2 10 2'+ 40 jiC] Figure 3 +0 25 40 ['C]

Claims (1)

[Claims] In a method for producing a thermal transfer recording medium in which a coloring material layer is coated on a support by a solvent coating method, a coloring agent, a resin, and a molten IJ! Coating made by dissolving or dispersing 1,100 g of a heat-fusible substance that does not dissolve at 40°C in a solvent 1) Spread the solution on the support, and then remove the soluble material. An IM manufacturing method for a thermal transfer recording medium, characterized in that: