JPS6044392A - Transfer-type thermal recording sheet - Google Patents

Abstract

PURPOSE:To obtain a recording sheet capable of easily transferring a dye, having high sensitivity and capable of transferring repeatedly, by providing a resin material layer comprising a dye, a material for melting the dye when being heated and a surface active agent and a sealing film for preventing the resin contained in the resin material layer from leaking. CONSTITUTION:A resin material 6 consisting of a mixture of a dye 5, a material for melting the dye when being heated and a surface active agent is applied to the sealing film 1 consisting of a polymer film such as cellophane and a polyethylene terephthalate sheet or a condenser paper, to obtain a transfer-type thermal recording sheet 4. The dye is preferably a dispersed dye based on anthraquinone or azo, and is used in an amount of 1-16pts.wt. per 8pts.wt. of a resin. The material for melting the dye when being heated may be glycerin or a glycol. A surface active agent having a melting point 40-100 deg.C is used. The resin is preferably a water-soluble resin such as polyvinyl alcohol.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of E-Start J] This invention 1 relates to a transfer type thermal recording sheet used for printing, for example, in a facsimile machine or a peripheral terminal printer.

[Prior art]

In recent years 1. Various non-impact type recording devices have been put into practical use. In particular, the thermal recording device 1q requires maintenance work 11υ.
V+V is used as an output device for information processing etc. because it eliminates noise, is noiseless and harmless, and has a simple device structure.
F' is expanding. For example, facsimile, 'l'i
This type of thermal recording device is increasingly being used as a printing means for output in peripheral terminal printers for i-calculators. There are two main types of thermal recording methods: chemical coloring type and transfer type. However, many chemically colored types are easily erased with plasticizers, solvents, adhesive tapes, etc., and they also have disadvantages such as easy additional printing and falsification, making them unsuitable for securities, legal documents, etc. Met. On the other hand, the transfer type has attracted particular attention in recent years as a method for overcoming the above-mentioned drawbacks.

As shown in FIG. 1, the thermal recording sheet (3) is attached to the transfer mold jl used in the conventional transfer type thermal recording method by sealing it with cellophane or parchment paper, etc. 11'; and a solid ink layer (2). 1. The solid ink layer (2) is made of carnauba wax or polyethylene glycol (with a melting point of 80° C. to 120° C.), polyethylene glycol, etc. (caust and dye are dissolved in a solvent, and the solid ink layer (2) is applied to a thickness of about 4 μm on the above-mentioned sealing JII. It is formed by coating with a wire paper or the like and drying.Thermal recording is performed by heating to dissolve the solid ink layer (2) and transferring it onto ordinary paper.

However, in order to improve resolution and sensitivity in the conventional transfer type thermal recording method, solid ink F! The thickness of i21 is 4
Generally, the thickness is about μm. For this reason, transfer can be performed only once, and for example, for recording on one A4 size sheet, it is necessary to use one A4 size transfer type heat-sensitive recording sheet. Therefore, it has been desired to develop a transfer-type heat-sensitive recording sheet that can be used repeatedly and has a high resolution.

In order to overcome the above drawbacks, a method has been proposed in which a carbon blank is dispersed in solid ink (2) to suppress the amount of ink elution. However, this method has the drawback that the carbon blank itself may be transferred onto the paper, and the reflection density of the printed area decreases with the number of transfers.

Therefore, as a way to improve this drawback, the special public
There is a dye transfer type heat-sensitive recording sheet described in Japanese Patent No. 8793. This method allows multiple transfers until the sublimable dye in the sheet is used up, but the sublimation temperature of the sublimable dye is high, and the temperature is 150°C to 200°C.
Because of the above, the sensitivity was poor.

[Summary of the invention]

This invention was made to eliminate the drawbacks of the conventional ones, and includes a material layer containing a dye, a material that dissolves the dye when heated, and a surfactant, and a surface of the material layer facing the thermal head. A transfer-type heat-sensitive recording sheet that is equipped with a sealing film that prevents the leakage of the resin material provided on the surface of the sheet, allows easy dye transfer, good sensitivity, repeatable transfer, and gradation recording. The purpose is to obtain.

[Embodiment of the Invention] Fig. 2 is a sectional view of a transfer type heat-sensitive recording sheet according to an embodiment of this invention l:j1. , and dye (6),
It consists of a resin material layer (6) containing a material that dissolves the dye when heated and a surfactant.

More specifically, a resin material mixed or dissolved with a dye (6), a material that dissolves the dye when heated, and a surfactant is applied onto the sealing film (on the transfer type heat-sensitive recording sheet (4)). Obtained by Shirukoshichi.

As the sealing film of this invention, for example, a polymer film such as cellophane or a polyethylene terephthalate sheet, or a capacitor film is used. In the case of water coating, a polyethylene terephthalate sheet whose surface has been made hydrophilic by corona treatment (for example, a diamond H3O0 manufactured by Boyle Co., Ltd.) is preferably used.

Any dye may be used as the dye of this invention, but anthraquinone-based and azo-based disperse dyes, for example, are preferably used because of their storage stability at room temperature and their solubility in materials that dissolve dyes when heated. . The blending ratio of the dye is preferably 1 to 16 parts by weight based on 8 parts by weight of the resin. If the coating is over 16 parts vertically, the coating will be brittle, and if it is less than 1 part by weight, the reflection density OD will not exceed 0.1.

Examples of the f'f(l1ti) of the present invention include water-soluble materials such as polyvinyl alcohol (PVA), polyvinylpyrrolidone, polyacrylamide, polyacrylic acid, polyethylene oxide, polyvinyl methyl ether, polyvinylpyridine, polystyrene sulfonic acid, gum arabic, and gelatin. Resins and oil-soluble materials such as polymethyl methacrylate can be used. However, in consideration of working environment, pollution-free, resource saving, etc., water-soluble resins are particularly preferably used among the above-mentioned resins.

In this invention, materials that dissolve dyes when heated, that is, materials that do not dissolve dyes when cold but only when hot, include (taking into consideration their compatibility with caustic materials, glycerin, diethylene glycol, triethylene glycol, Glycols such as pyrene glycol and polyethylene glycol with a low molecular weight (molecular weight of 1000 or less) are preferably used. In Fig. 3, polyvinyl alcohol is used as the resin of a transfer type 16 thermal recording sheet using neck paper as a recording medium. (PVA), azo disperse dye as dye,
The relationship between the amount of glycerin added when glycerin is used as the material described in "":'j[i[5PVA] and the reflection density (OD) of transfer printing is shown, and the effect of adding the above-mentioned material is shown.

As you can see from the diagram, PVA8 Shigekawabe Hill and Grise92
If it is less than 10 parts by weight, there is no effect, and if it is more than 25 parts by weight, the coating film will not dry and become unusable. 10 to 25 parts are preferably used.

Examples of the surfactant of the present invention include sorbicun monopalmidate (melting point 47°C, trade name Span 40),
Sorbitan monostearate (melting point: 54°C, trade name: Span 60) and other materials having a melting point of 40 to 100°C and which are solid at room temperature are used. If the melting point is below 40℃, there will be a lot of background fogging (
, sensitivity (OD
) becomes lower.

FIG. 4 also shows that plain paper is used as the recording medium, 8 parts by weight of PVA and 8 parts by weight of azo disperse dye (manufactured by Hodogaya Chemical Co., Ltd., trade name 0H-B) are used as the resin composition of the transfer type heat-sensitive recording sheet.
0,6,10 respectively with 20 parts by weight of glycerin
, 11.14 parts by weight of surfactant (span 40, melting point 4
7°C) is used. In this case, the method for preparing the transfer-type heat-sensitive recording sheet and the method for transferring were the same as in Example 1 described below. As can be seen from the figure, it is preferable to add 1 to 20 parts by weight per 8 parts by weight of the resin (preferably 14 parts by weight plus 14 parts by weight for a span of 4 degrees and 2 degrees). There is no effect if the single layer I is less than 4 parts, and if it is more than 20 parts, the background fog is large. In other words, when a surfactant is added, a favorable result has been obtained in which the resin is not transferred to the recording medium even if the transfer-type heat-sensitive recording sheet is heated above the glass transition temperature (contrary to the conventional glass transition temperature). It has been found that the addition of the agent also has an effect on the sensitivity of the transfer-type heat-sensitive recording sheet.

In other words, in a mixture of PVA and glycerin, even if the maximum Fd of glycerin (25 parts by weight of glycerin to 17 parts by weight of PVA to 8 parts of hX) is added, the
The OD when a 0-weight weight is placed on it for 5 seconds is at most 06, but this is compared to Solpicun Monooleate (trade name Span 80), a surface-elevating agent.
ii jft t! When B/& is added, OD reaches 1.0. However, this one is an IRf2 head (16V, 1
001(z, pulse application time 2ms, paper feed speed 16'
/S), a background fog of 0.2 OD occurred. After conducting extensive research to remove this background fog, it was discovered that a surfactant having a melting point within the above range could be used.

For reference, the recording medium used for the transfer-type heat-sensitive recording sheet of the present invention is, for example, plain paper, and in the case of a plastic sheet with a smooth surface, rubbing the surface will settle the transfer print, so the surface is used as a rough embossed ticket.

The transfer-type thermosensitive recording sheet of the present invention constructed as described above is superimposed on a recording medium such as plain paper, and the conditions are as follows: an applied voltage of 16 V, a pulse-to-pulse wave number of 100 Hz, a pulse application time of 2 ms, and a paper feed speed of 16 g/S. When printing with a thick-film head, the heat generated by the thermal head reaches the resin material layer through the sealing film, and when heated, the dye is dissolved in the dye-dissolving material and surfactant, and these liquids are dissolved. The mixture is transferred to the recording medium surface. At this time, only a portion of the mixture is eluted due to its adsorption to the resin, so it can be used repeatedly, and since the amount of dye dissolved is proportional to the temperature, gradation can be obtained.

The present invention will be explained in more detail with reference to Examples above, but the present invention is not limited thereto.

Example 1 8 parts by weight of I'VA, 8 parts by weight of an azo disperse dye (manufactured by Hodogaya Chemical, trade name 0H-Blue), 20 parts by weight of glycerin, 10 parts by weight of surfactant sorbitan monopalmy Tate (trade name: Span 40G) and 10 parts by weight of water (1 part by weight) are refined in a ball mill all day and night.
It was coated with a wire bar to a thickness of 5 μm on a 2 μm corona-treated polyethylene terephthalate sheet (manufactured by Diafoil, trade name H3O0) and dried.

To this, a thick film head is applied with a voltage of 16 V and a pulse frequency of 10
0Hz, 2ms during pulse, paper feed speed x6. When printed under JS conditions, the reflection density on plain paper was 0D=1.
1 print was obtained. When this transfer-type heat-sensitive recording sheet was repeatedly used for recording on plain paper, it was possible to use it with almost no drop in reflection density after 10 recordings.

Example 2 Polyvinylpyrrolidone with 1-fold weight loss: Anthraquinone-based disperse dye with 10-layer weight loss (manufactured by Mitsubishi Kasei, trade name: p)
rB-77), 15 parts by weight + B parts of diethylene glycol, 11 F (t jtt parts by weight) of the surfactant sorbicun monosdaleate (trade name Span 60) and 100 parts by weight of water are kneaded in a ball mill all day and night.This kneaded product is It was applied to a 20 μm thick capacitor paper with a tsuya par to a thickness of 4 trm and dried. This was layered with a polyethylene terephthalate sheet whose surface had been roughened with sandpaper, and a thin film head was used to apply a voltage of 6V, 1 pulse, and 100Hz.
1 pulse application time 3ms 1 low feed i+iI degree 16.
, /S, printing was obtained on the polyethylene terephthalate sheet with reflection +1k degree 0D-1,3. Even if I rubbed this thing with paper, the print G1≦ stains could not be removed, and I repeatedly recorded the marks on a polyethylene terephthalate sheet using this transfer type heat-sensitive recording sheet, but 10
Until now, I was able to use it almost without incident due to its reflective density.

Example 3 When recording was performed under the same conditions as Example 1 except that glycerin in Example 1 was replaced with diethylene glycol, the reflection density of the print was 0D=1.2.

Comparative Example When the surfactant span 40 in Example IK was added to the span 80 whose melting point was below room temperature, and the temperature was recorded under the same conditions as in Example 1, a large background fog occurred, and the ODi of the background fog was It was 0.2.

[Effects of the Invention] As explained above, this I3A is provided in a resin material layer containing a dye, a material that dissolves the dye when heated, and a surfactant, and in a region facing the heat head of this resin material layer. By using a sealing film that prevents leakage of the resin material, dye transfer is easy and sensitivity is high.
It is possible to make a transfer 1-1 M recording sheet that is capable of vinegar transfer and gradation recording.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a conventional transfer type Iδ thermal recording sheet, Fig. 2 is a sectional view of a transfer type V & thermal recording sheet of an embodiment of the present invention, and Fig. 3 is a glycerin in an embodiment of the invention. ” ” (”'8 ff t31 (PVA) Characteristic diagram showing the change in reflection density (OD) of printing, Figure 4 shows the addition of surfactant in another example of this flower mei (-Man! Eyebrows-
i Saiki A) Reflection of printing by VC) It is a characteristic diagram showing changes in agricultural degree (OD). In the figure, (l) is a sealing film, (2) is a solid ink layer,
(3) is a transfer type heat-sensitive recording sheet), +4) is a transfer type heat-sensitive recording sheet, (5) is a dye, and (6) is a resin material layer. Note that the same reference numerals in the drawings indicate the same or fourth eye portions. Agent Masu Oiwa Leaving work 1 Figure 21 S1 Figure 4 σD Procedural amendment (voluntary) 1 effect 'IJ1 Director 1, 1t f! Display of l! 1-1-Gusho 58-15
8784 No. 2, Title of invention Transfer type thermal recording sheet:
3 Representative of the person making the amendment and Katayama f-: Part 2, ... ~ 5, 41Yj of the detailed description of the invention subject to the amendment 6. Contents of the amendment (1) @Page 3 of the specification In line 18, "according to one method" should be corrected to "according to the method." (2) Correct "Span 406 J" in line 6 of page 11o to "Span 40)". From then on

Claims (1)

[Claims] A frJI resin layer containing a dye, a material that dissolves the dye when heated, and a surfactant with a melting point of 40 to 100°C, and the resin paulownia layer were provided on the surface facing the thermal head.
A transfer type heat-sensitive recording sheet equipped with a sealing film to prevent leakage of the resin material.