JPS59201894A - Thermal transfer material - Google Patents

Abstract

PURPOSE:To produce a transferred image with high quality even on a recroding medium having poor surface smoothness, by a method wherein a particulate form filler containing a readily volatile organic liquid is incorporated into a heat-transferrable ink layer, in a thermal transfer material comprising a heat- transferrable ink layer on a base. CONSTITUTION:A coated layer 3 of a heat-fusible ink in which a particulate form filler 5 containing a readily volatile organic liquid is dispersed in a heat- fusible binder 4 containing a colorant dispersed or dissolved therein, is provided on the base 2 consisting of a known film or paper with or without a heat-resistant protective layer provided thereon. An ordinary colorant and an ordinary heat-fusible binder are used. A compound such as an aliphatic or aromatic hydrocarbon having a boiling point of not higher than 130 deg.C is used as the readily volatile organic liquid, and is incorporated into particulates of a resin by impregnation or in a microencapsulated form. The particle size of the filler is set to be 0.1-30mum, and the filler is dispersed in the binder in a quantity of not more than 50 parts per 100 parts of the binder.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermal transfer material that provides a transferred recorded image of good print quality even on a recording medium with poor surface smoothness.

In recent years, with the rapid development of the information industry, various information processing systems have been developed, and recording methods and devices suitable for each information processing system have also been developed and adopted. One such recording method is the thermal recording method, which uses a compact and compact device that is noiseless.
It has excellent operability and maintainability, and has been widely used recently.

However, among the recording papers used in thermal recording methods, ordinary thermal recording paper is a color-forming processed paper containing a color former and a color developer, so it is expensive, and records can be tampered with. The paper has disadvantages in that it has poor storage stability, such as the paper easily developing color due to heat or organic solvents, and the recorded image fading in a relatively short period of time.

Thermal transfer recording method has recently been attracting particular attention as a method that maintains the advantages of the above-mentioned thermal recording method and compensates for the disadvantages associated with the use of thermal recording paper. A heat-sensitive transfer material prepared by melt-coating a heat-transferable ink consisting of a colorant dispersed in a heat-melting binder on a support I- is used, and the heat-transferable ink layer of the heat-sensitive transfer material is applied to a recording medium. The ink layer is superimposed on the recording medium so as to be in contact with the recording medium, and heat is applied from the support side of the thermal transfer material to the recording medium to transfer the melted ink layer to the recording medium. It forms a transfer ink image. According to this method, it is possible to maintain the advantages described in -1- of the thermal recording method, and to use passing paper as a recording medium, and also to avoid the disadvantages associated with the use of thermal recording paper described in 1-1. Can be removed.

However, conventional thermal transfer recording methods are not without drawbacks. In the conventional thermal transfer recording method, the transfer recording performance, that is, the printing quality, is greatly affected by the surface smoothness. Good printing is performed on highly smooth recording media, but good printing is performed on recording media with low smoothness. In some cases, the print quality deteriorates significantly. However, even when using paper, which is the most typical recording medium, highly smooth paper is rather special, and ordinary paper has various degrees of unevenness due to entangled fibers. Therefore, in the case of paper with large surface irregularities, the hot melted ink cannot penetrate into the fibers of the paper during printing and is deposited only on the convex parts of the surface or in the vicinity thereof, so the rims of the printed image The image may not be sharp or some parts of the image may be missing, resulting in poor print quality. Furthermore, in order to improve print quality, it is possible to use a heat-melting paint with a low melting point, but in this case, the heat-transferable ink layer becomes sticky even at relatively low temperatures, and This causes inconveniences such as poor print quality and staining of non-printing areas of the recording medium.

The main purpose of this invention is to eliminate the drawbacks of the conventional thermal transfer recording method mentioned above, and to produce high quality recording media not only for recording media with good surface smoothness, but also for recording media with poor surface smoothness. An object of the present invention is to provide a heat-sensitive transfer material that can provide accurate printing.

According to research conducted by the present invention, it has been found that dispersing a fine particulate filler containing an easily volatile organic liquid in the thermally transferable ink layer is extremely effective in achieving the above objective. Served. That is, when the thermally transferable ink layer thus formed is heated in contact with a recording medium, the thermally meltable binder in the thermally transferable ink layer is melted or softened, and the thermally transferable ink layer has transferability to the recording medium. At the same time, the easily volatile organic liquid contained in the fine granular filler vaporizes, and its pressing force allows the ink to penetrate into the four parts of the surface of the recording medium or into the inside of the fiber structure. . Therefore, even on a recording medium with poor surface smoothness, defects in the printed image and the occurrence of haze can be prevented, and the printing quality can be improved.

Furthermore, since the easily volatile organic liquid is encapsulated in the fine particulate filler, it does not lower the melting point of the entire thermal transferable ink layer or deteriorate its storage stability before use.

The heat-sensitive transfer material of the present invention is based on the findings described in -, more specifically, it is formed by forming a heat-transferable ink layer on a support, and the heat-transferable ink layer is formed of a heat-melting paint ink. 4+jyI is obtained by dispersing a coloring agent and a fine particulate filler containing an easily volatile liquid.

The present invention will now be described in further detail with reference to the drawings as necessary. In the following description, "
Unless otherwise specified, "%" and "part" are tun 11 no, (
standard.

FIG. 1 is a schematic cross-sectional view in the thickness direction of a thermal transfer material in the most basic embodiment of the present invention. That is, thermal transfer material l
is usually a sheet (used to include film)
A thermally transferable ink layer 3 is formed on a support 2 having a shape.

As the support 2, conventionally known films and papers can be used as they are, such as films of relatively heat-resistant plastics such as polyester, polycarbonate-1, triacetylcellulose, nylon, polyimide, etc. For N, parchment paper or the like can be suitably used.The thickness of the support is preferably about 2 to 15 microns when considering the heat source as a heat source during thermal transfer. For example, there are no particular restrictions when using a heat source that can selectively heat the thermal transfer ink layer, such as a laser beam.Furthermore, when using a thermal head, silicone may be added to the surface of the support that comes into contact with the thermal head. The heat resistance of the support can be improved by providing a heat-resistant protective layer made of resin, fluororesin, polyimide resin, epoxy resin, phenol resin, melamine resin, nitrocellulose, etc., or it is possible to improve the heat resistance of the support. It is also possible to use support materials that were not previously available.

The thermal transfer ink layer 3 is made by dispersing a heat-fusible binder 4 made by dispersing or dissolving a colorant (not shown in 41F), and a fine particulate filler 5 containing an easily volatile organic 1α form. Consists of a coating layer of heat-melting ink.

As the heat-melting ink composed of a colorant and a heat-melting paint, those conventionally used in heat-sensitive transfer materials can be used as they are. That is, as the colorant, various dyes, pigments, or carbon blanks widely used in the fields of printing and recording can be used. In addition, as heat-melting/haingoos, one laths such as carnaupa wax, paraffin wax, zasol wax, microcrystalline wax, and castor wax, nistearic acid,
Higher fatty acids such as palmitic acid, lauric acid, aluminum stearate, lead stearate, barium stearate, lead IIF stearate, palmitic acid, methyl hydroxystearate hydroxystearate, or derivatives thereof such as metal salts and esters; Olefins such as polyethylene, polypropylene, polyisobutylene, polyethylene wax, polyethylene oxide, polytetrafluoroethylene, ethylene-acrylic acid copolymer, ethylene-ethyl acrylate copolymer, ethylene-hinyl acetate copolymer, etc. Thermoplastic resins made alone or consisting of copolymers, derivatives thereof, etc. are used.These thermoplastic resins may be used alone or in a mixture of two or more.

The heat-melting ink constituting the heat-transferable ink layer 3 includes l,
It is made by dispersing fine particulate filler 5 containing an easily volatile organic liquid in the ordinary heat-melting ink described above. Easily volatile organic liquids are generally impregnated with microscopic particles of resin or encapsulated in the form of microcapsules. Easily volatile organic liquids include compounds that are generally used as evaporative blowing agents or easily volatile blowing agents in the field of resin conditioning, etc.
It can be used as is in the present invention. Easily volatile organic liquids are
+a It is selected depending on the form contained in the granular filling material, or it is generally liquid at the field temperature and pressure, and is 130%
Compounds having a boiling point below 100°C, especially above 100°C, are preferably used. Examples of typical easily volatile organic liquids are shown below.

(a) Aliphatic hydrocarbons such as n-propane, n-pentane, n-hexane,
Hydrocarbons having 4 to 7 carbon atoms such as neopentane, isohexane, n-heptane, isoheptane. These have low dielectric properties and are inexpensive.

(Ex) 11A hydrogenated aliphatic hydrocarbons such as methyl chloride, -'-methylene chloride, trichloroethylene, dichloroethane (Sym), etc.

(c) Fluorinated aliphatic hydrocarbons such as Freon-11 (CC13F), Freon-12
(CC12F2), Freon-21 (CHCI F)
, Freon-22 (-CHCIF2), Freon-113 (CCIF-CCIF, ), Freon-114 (CCIF-CCIF2), and other chlorine-fluorine conductors of methane or ethane are often used.

(2) Aromatic hydrocarbon type Benzene, L. Luen, etc.

These easily volatile organic liquids and fine particulate fillers encapsulating the body can be obtained by a known resin impregnation method or microencapsulation method. In the case of the resin impregnation method, for example, a method in which a readily volatile organic liquid is added during the suspension polymerization of suitable pieces (Japanese Patent Publication No. 33-3190), or a piece obtained by suspension polymerization is added with a solvent, etc. A method of swelling and adding an easily volatile organic liquid (Japanese Patent Publication No. 36-10628) is adopted. If necessary, a method may be adopted in which the resin is made fine and then impregnated with an easily volatile organic liquid.

Also, in the case of microencapsulation, complex coacervation fJ=. Known methods such as interfacial polymerization and phase separation can be employed. Microcapsules containing easily volatile organic liquids are commercially available, such as Acid Matsumoto Microsphere F30 manufactured by Matsumoto Yushi Pharmaceutical Co., Ltd.
Examples include F2O, F2O, and Expancel (manufactured by Ippon Fillite Co., Ltd., which contains a blowing agent isobutane with a wall material made of a monostrenyl hynylidene/acrylonitrile copolymer).

1- Including those mentioned above, fine particulate fillers containing easily volatile organic liquids have a particle size of 0.1 to 30 microns,
Particularly, those having a particle size of 0.1 to 10 microns are used, and among them, those having a small particle size are preferably used.

In the thermal transferable ink layer 3, it is preferable that 50 parts or more of a fine particulate filler be dispersed in 100 parts of the above-mentioned heat-melting paint.

The heat-sensitive transfer material 1 according to the present invention is produced by applying a heat-melting ink consisting of a particulate filler containing a heat-melting binder, a coloring agent, and a readily volatile organic liquid as described in 1. The thickness of the heat transferable ink layer 3 obtained by coating the support 21-14T and drying to form the heat transferable ink layer 3 is 1 to 30 microns in AQ, and is in the range of 2 to 20 microns. is preferred.

The planar shape of the thermal transfer material of the present invention is not particularly limited, but it is generally used in the form of a typewriter ribbon or a wide tape used in line printers. Further, for color recording, it is also possible to use a heat-sensitive transfer material in which heat-melting inks of several different tones are applied in stripes or blocks.

Next, a thermal transfer recording method using the thermal transfer material described in -1 will be described using the most typical thermal head as a heat source. FIG. 2 is a schematic cross-sectional view in the thickness direction of a thermal transfer material showing its outline. That is, the recording medium 6 is brought into close contact with the heat-melting ink 3 of the thermal transfer material 1, and if necessary, a heat pulse is further applied by a thermal spatula F' 8 while applying a heat pulse from the back side of the recording medium by a platen 7.
The ink layer 3 is locally heated according to the printing or transfer pattern at the location r7j. The heated part of the ink layer 3 has a temperature of -1
-I! When the water reaches a certain temperature, it softens or melts, and the fine granular filler containing the easily volatile organic liquid dispersed in the ink layer 3 is also heated, so the easily volatile organic liquid evaporates. oxidizes and generates gas.

Due to the volumetric expansion of the ink layer due to the generated gas and the pressure of the scum, it is possible to sufficiently ink infiltrate and fill four parts of the surface of the recording medium that could not be penetrated with conventional thermal transfer ink, making it possible to completely penetrate recording media with poor surface smoothness. It is also possible to obtain a recorded image 3a with good print quality.

In Section 1-1, an example in which a thermal head is used as a heat source for thermal transfer recording has been described, but it is easy to understand that the same method can be used when using other heat sources such as laser light.

As explained in detail in 1-11 below, the heat-sensitive transfer +, 5 of the present invention
(The material contains an easily volatile organic liquid in the thermal transfer ink layer.)
By doing so, it is possible to perform recording with good print quality even on a recording medium with poor surface smoothness, and the storage stability of the thermal transfer material does not deteriorate as a result.

Therefore, it is thought that it can be widely applied to information recording systems that will become more diverse in the future.

Hereinafter, the present invention will be explained in more detail with reference to Examples.Example 1: 1 part of carbon blank, 2 parts of polyethylene wax (softening point 70°C) and 1 part of carnauba wax were mixed with about 10%
Using an attritor while heating to 0°C, the molecule f! 1
．． Mixed. Next, petroleum-based solvent (product name: Near Invar H)
, manufactured by Enso) was added thereto, heated to about 100°C, and cooled to room temperature while stirring vigorously (11) to obtain Isopar H liquid in which carbon black/wax was finely dispersed. Furthermore, 1 part of a particulate filler containing an easily volatile organic liquid (trade name: 2 Micro Square F, manufactured by Matsuki Yushi Seiyaku Co., Ltd.) was added to the dispersion and stirred and mixed to obtain a coating liquid. wood coating liquid,
6 micron thick polyester film] Second, it was coated, dried, and a thermal transfer material having a transfer ink layer thickness of 10 microns was prepared (11). 16 Using heat-sensitive transfer material, the electrophotographic chart is used as a document to print on paper with different smoothness using a heat-sensitive transfer facsimile machine.
1-, and the resolution was evaluated. the result,
Berakumo smoothness 6.3 wood/m for paper with 100 sec
The resolution of m is 5.6 wood/for 15 seconds of paper.
Recordings with a resolution of mm were obtained. In addition, the clarity of the recorded image was good for all papers. Only the isopar liquid in which the carbon blank/one lath of Comparative Example 1 was finely dispersed was applied to the 6 micron polyester film L. A thermal transfer material having an ink layer thickness of 10 microns was obtained which could be dried and rolled.

Using this thermal transfer material, the resolution of the recorded image was evaluated in the same manner as in Example 1 for thermal transfer recording. As a result, a resolution of 6.3 wood/mm was obtained for paper with Henk 11 smoothness of 100 seconds, but a resolution of 3.6 wood/mm for paper with 15 seconds [Kawa ~ Also, the resolution of the recorded image was low. The clarity was also poor.

Example 2 A thermal transfer material was obtained in the same manner as in Example 1 except that fine particles obtained by crushing butane-containing styrene beads were used instead of the microspheres of Example 1. By using this heat-sensitive transfer material, high-resolution recording similar to that in Example 1 was possible.

[Brief explanation of drawings]

FIG. 1 is a schematic cross-sectional view in the thickness direction of an embodiment of the thermal transfer material of the present invention, and FIG. 2 is a thermal transfer material for explaining an embodiment of a thermal transfer recording method using the thermal transfer material of FIG. 1. FIG. I... Thermal transfer material 2... Support 3... Thermal transfer ink layer 4.・ΦNetsuhen F r-Itozoki Neyama 1-1 Yen -÷ May 1981 2z11 'J'l, PI IJ Director Kazuto Wakasugi 1 general ('I!1
1P mouth j * examiner 1) j,・IX table/J\ 1'7i Japanese 58 years J! I' + i'l Application No. 76179 2, name of the invention Rito Dog,! L i+,, ′su゛
Material 3.7 Yama 1 [Relationship with case 1 and 7 Special training applicant (100) Canon Co., Ltd. 4, agent ii) Location 2-7-7 Higashi-Shinbashi, J-8 Ward, Tokyo 105 New Paper Kokusai Hill 6th floor details 1 "U' and 1411 11T detailed 1 explanation" 16 Supplement II contents details Hot water temperature J4 Tei fIN+ [(softening point 70°O) J
[(Soft (L point 95℃) 1 part, paraffin wax (softening point 70) 0CJ and sleeve 11.

Claims (1)

[Claims] A thermally transferable ink layer is formed on a support, and the thermally transferable ink layer is formed by dispersing a colorant and a fine particulate filler containing an easily volatile organic liquid in a heat-melting binder. A heat-sensitive transfer material characterized by: