JPS63134273A - Thermal transfer sheet - Google Patents

Abstract

PURPOSE:To easily judge whether a prescribed number of frames has been completed or not by forming a letter of a mark indicative of the completion of the prescribed number of the frames on a thermal transfer layer on a thermal transfer sheet in the neighborhood of its final end. CONSTITUTION:A thermal transfer sheet 1 has a thermal transfer layer 3 on a substrate sheet 2 and the inversion of letters 'END' as an end mark 4 on the part of the thermal transfer layer 3 corresponding to a portion to which an image in a final frame is transferred. Certainly, the end mark 4 is not limited to the exemplified letters 'END'. Thus, since arrival at the final frame of the thermal transfer sheet or approach thereto is known only from a glance at a hard copy only by effecting transfer copying, an increase in the mechanism of a printer or in processing steps in manufacturing the thermal transfer sheet is unnecessary.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a thermal transfer sheet for forming an image on paper or the like by heating it in a pattern using a thermal head or the like.

[Conventional technology]

For the purpose of creating a hard copy from an image signal, a thermal transfer sheet having a heat-melting transfer layer made of heat-melting wax or the like colored with a pigment is printed on paper, or
A thermal transfer sheet using a sublimable dye together with a binder is layered on image-receiving paper, which is paper coated with a polyester resin, etc., and an image is formed by heating the sheet from the back side with a thermal head, etc. It is.

According to these methods, images can be formed according to the input information, and in the latter case in particular, images with gradation can be obtained by controlling the thermal energy applied during heating, which is similar to color prints using silver halide photography. Since hard copies of equivalent quality can be obtained, it has begun to be used for various purposes.

[Problem that the invention seeks to solve]

Normally, these thermal transfer sheets are made in such a way that they can form several dozen screens (frames) of a certain size.
It is supplied to the user in a rolled long sheet.

However, although the number of screens (number of frames) that can be formed is predetermined, there is no way to check whether the specified number of sheets has been completed by counting the number of hard copies that have been formed. The printer used for
The only way to make a decision was to deal with it mechanically.

For example, there is a mechanism within the printer that counts the number of sheets formed on the screen, a mechanism that notifies the counted number using a display tube or lamp, or a mechanism that detects the end of the sheet with some kind of mark.

However, in either case, it is necessary to increase the number of printer mechanisms, and in the latter case, it is necessary to add a mark to the sheet for detection.

This invention attempts to solve the problem of requiring an increase in the number of mechanisms and, in some cases, an increase in processing steps during the production of the heat-sensitive transfer sheet, by improving the heat-sensitive transfer sheet.

[Means for solving problems]

In this invention, the problem can be solved by forming characters or marks on the heat-sensitive transfer layer on the heat-sensitive transfer sheet near the end of the sheet to indicate the end of the specified number of sheets.

That is, the present invention provides a thermal transfer sheet having a thermal transfer layer on an rJfH material sheet, in which the layer itself is melted by heat or the dye in the layer is melted or sublimated and transferred, and the layer is transferred near the end of the sheet. A heat-sensitive transfer sheet characterized by having a portion onto which an end mark pattern can be transferred.''

FIG. 1 shows the basic form of the heat-sensitive transfer sheet of the present invention. The heat-sensitive transfer sheet 1 has a heat-sensitive transfer layer 3 on a base sheet 2, and an end mark 4 is provided on a part of the heat-sensitive transfer sheet 1. rEND, which means ``J'', is provided in the heat-sensitive transfer layer corresponding to the part to which the image of the final frame is transferred.

Here, the end mark 4 is not limited to the illustrated rENDJ, but may be "end" or may be a predetermined figure or symbol indicating the final frame. Alternatively, as shown in Figure 2, part of the screen (
For example, if the end of the screen is displayed by cutting off the lower right corner of the screen and the end is displayed, the screen becomes too small.
It has the advantage of not being ropey.

Also, the end mark 4 is formed only in the last frame,
You can start one step before the end, or even several steps before the end. In such a case, the remaining number of sheets may be indicated, or the number of sheets that can be formed may be 5, for example.
If it is 0, it may indicate the frame number itself, such as 48.49.50.Of course, each frame number may start from 1 and be attached to all frames, but it indicates the end. There is no need to number all the frames if you can read them.

As shown in FIG. 1, the end mark 4 may be formed at any position, such as at the bottom right of the screen or at another position. If there is a margin on either the top, bottom, left or right, it may be provided so that the image is transferred to that margin.

The end mark 4 may be formed in a different hue from that of the part for forming the image, but the normal! j! , thermal transfer layer 3
A white part may be formed as a white part in a part of the image.To provide a white part, that part can be cut out when forming the heat-sensitive transfer layer, or once it has been formed, it can be heated and transferred. It can also be provided by methods such as partially removing the layer or providing a layer that prevents transfer on the once formed transfer layer.

The heat-sensitive transfer layer 3 and the end mark 4 may be formed as a heat-sensitive sublimation transfer layer containing a sublimable dye, or may be formed as a heat-sensitive melting layer containing a non-sublimable colorant in a heat-melting binder. They may be formed as a transfer layer, or one of them may be a heat-sensitive sublimation transfer layer and the other may be a heat-sensitive melting transfer layer.

In Figure 1, each frame is depicted as if it were for single-color transfer in order to simplify the explanation, but this type of thermal transfer sheet is shown as (Y) (M) (C) ( It usually has a layer for transferring yellow, magenta, cyan, and blank colors shown in Bk), and if these four colors (sometimes three colors excluding black) are counted as one frame, The above explanation still applies. The end mark may be attached to any area among the three to four color areas for one frame, or may be attached to a plurality of areas.

In order to manufacture the heat-sensitive transfer sheet of the present invention, the same materials as those for a normal heat-sensitive transfer sheet having only a uniform heat-sensitive transfer layer may be used, and are as follows.

(Sheet-like base material) As the base sheet 2 in the present invention, polyester, polypropylene, cellophane, polycarbonate, cellulose acetate, polyethylene, polyvinyl chloride, polystyrene, nylon (polyamide), aromatic polyamide (aramid) can be used as the plastic film. , polyimide,
Polysulfone, polyvinylidene chloride, polyvinyl alcohol, fluorine resin, hydrochloric acid rubber, ionomer, etc., and as paper, condenser paper, etc. can be used. Among these, plastic films are preferred because they have a smooth surface and high mechanical strength, and among them, polyester films and aramid films are preferably used.

The thickness of the base sheet 2 is 2 to 50 μm, preferably 2 to 50 μm.
It is 12 μm.

(Thermal Transfer Layer) The thermal transfer layer 3 contains a non-thermal transferable binder containing a dye that is transferred by melting or sublimation when heated.

The dye is preferably a sublimable disperse dye, a sublimable oil-soluble dye, or a sublimable basic dye, and has a molecular weight of 1.
50-800, preferably 350-700. In addition to dyes that sublimate and transfer, dyes that melt and transfer when heated can also be used. These dyed Gini 1
is selected taking into account sublimation temperature, hue, weather resistance, solubility in ink or binder resin, etc., and is selected, for example, as follows.

C, 1, (abbreviation for chemical index, the same applies below) Disperse Yellow 51° 3, 54, 7
9, 60, 23, 7, 141°c, r', Disperse Blue 24, 56, 14,
301, 334, 165, 19, 72, 8
7, 287, 154, 26, C,! , Disperse Red 135, 146, 59, 11 73, 60, 167, C,1, Disperse Violet 4, 13, 36
, 56, 31°C, 1, Solvent Violet 13, C, 1, Solvent Black 3, C, 1, Zurhentgelin 3, C, 1, Solvent Yellow 56, 14, 1G, 29, C, 1, Solvent Blue 0. Same 35, Same 63, Same 3
6, 50, 49, 111, 105, 97, 11, C, 1, Turben Trend 135, 81, 18, 25, 19, 23, 24, 143, Same 146,
As the binder for the 182° heat-sensitive transfer layer, a binder that does not transfer dye itself even if the amount of heat necessary for dye transfer is applied is used. For example, ethyl cellulose, hydroxyethyl cellulose, ethyl hydroxy cellulose, hydroxypropyl cellulose, methyl cellulose, cellulose acetate, vinegar 1
l) l! Cellulose resins such as acid cellulose, vinyl resins such as polyvinyl alcohol, polyvinyl butyral, polyvinylpyrrolidone, polyester, polyvinyl acetate, and polyacrylamide can be used.

As an example of a more preferable binder, instead of the usual polyvinyl butyral resin mentioned above, a binder with a molecular weight of 60,000
0 to 200,000, the weight percent of the vinyl alcohol moiety in the polyvinyl butyral resin is lθ to 40%, preferably 15 to 30%, and the glass transition point is 60°C to 110°C, preferably 70°C to 110°C. Special polyvinyl butyral resins may be mentioned. If the molecular weight is less than 60,000, the cohesive force as a binder is insufficient;
If it exceeds 0, the viscosity during coating becomes too high, causing problems in coating. If the vinyl alcohol content is less than 10%, the stability of the heat-sensitive transfer layer over time will be insufficient, resulting in dye aggregation, precipitation, and bleeding to the surface.On the other hand, if it exceeds 40%, the polyvinyl alcohol content will be insufficient. Printing by preventing sublimation of the dye due to the affinity of the part for the dye? degree decreases.

The weight ratio of dye and binder in the thermal transfer layer is dye/binder.
It is desirable that the binder is 0.3 or more, and 0.3
If it is less than that, the print density and thermal sensitivity will be insufficient. Also, dye/
If the binder exceeds 2.3, the retention of the dye in the binder becomes insufficient, and the storage stability of the thermal transfer sheet deteriorates. Therefore, the dye/binder ratio is preferably 0.3 to 2.3, more preferably 0.55 to 1.5.

Preferably, the dye is dissolved in the binder of the thermal transfer layer. In conventional sublimation transfer paper for textiles, dyes are dispersed in a binder, so it is necessary to provide energy to overcome the interactions between dye molecules, which inevitably requires high energy. Fever drops to 53 degrees. In this respect, it is advantageous in terms of heat sensitivity if the dye is dissolved in the binder.

The dye and binder are kneaded together with a solvent to a predetermined ratio, preferably dissolved in the solvent to form an ink composition, and the ink composition is printed or applied onto a sheet-like substrate using a known printing method or coating method. be done.

(Heat-melting transfer layer) Heat? The 8-melt type transfer layer consists of a binder and a colorant that melt when heated.

Binders include wax, drying oil, resin, mineral oil,
Derivatives of cellulose and rubber, etc., and mixtures thereof are used.

As the binder wax, microcrystalline wax, carnauba wax, and paraffin wax are preferably used, and in addition to these, Fuinosha Tropschwax, various low-molecular-weight polyethylenes, some modified waxes, fatty horse stell, amides, Wood wax, beeswax,
Various waxes can be used, such as spermaceti wax, wart wax, wool wax, shellac wax, candelilla wax, and petrolatum.

Examples of the binder resin include EVA.

EEA, polyethylene, polypropylene, polybutene,
Petroleum resin, vinyl chloride resin, polyvinyl alcohol, vinylidene chloride resin, methacrylic resin, polyamide, polycarbonate, 1 m II! , polyvinyl formal, polyvinyl butyral, acetyl cellulose, nitrocellulose, acetic acid M vinyl resin, polyisobutylene, polyacetal, or the like can be used.

The colorant is preferably an organic or inorganic pigment or dye that has good properties as a recording material, such as one that has sufficient color density and does not discolor due to light, heat, or humidity. It is not preferable to use a coloring agent that melts or sublimes in the binder of the heat-melting transfer layer, and a colorant that does not sublimate is used.

The hot-melt transfer layer is made into a hot-melt ink by melting and mixing the above-mentioned binder and colorant, and in addition to hot-melt coating on a sheet-like substrate, it can also be coated with a conventional printing or coating method, or by a specific method. The coating can be applied by methods such as hot rough car coating, gravure coating, gravure reverse coating, roll coating, gravure printing, bar code, etc., and the thickness is usually 0.1 to 30 μm.
Preferably it is 1 to 20μ.

(Other configurations) For the thermal transfer sheet, anti-sticking treatment is applied to the side of the sheet-like base material on which the thermal transfer layer is not provided, in order to prevent sticking caused by the heat of the thermal head and improve slippage when printing from the back side. It is better.

For example, it is preferable to provide a heat-resistant slip layer mainly consisting of (1) a reaction product of a polyvinyl butyral resin and an isocyanate, (2) an alkali metal salt or alkaline earth metal salt of a phosphoric acid ester, and (2) a filler. Polyvinyl butyral resin has a molecular weight of about 60,000 to 200,000 and a glass transition point of 60 to 110°C.
In addition, from the viewpoint of having many reaction sites with isocyanate, the weight% of the vinyl alcohol part is 15 to 40%.
The one is good.

As the alkali metal salt or alkaline earth metal salt of the phosphoric acid ester, Gafac RD720 manufactured by Toho Chemical Industry Co., Ltd. is used, and it is preferably used in an amount of 1 to 50% by weight, preferably 10 to 40% by weight, based on the polyvinyl butyral resin.

The heat-resistant slip layer preferably includes a heat-resistant layer as a lower layer, and is made of a combination of a synthetic resin that can be cured by heating and its curing agent, such as polyvinyl butyral and polyvalent isocyanate, acrylic polyol and polyvalent isocyanate, cellulose acetate and titanium chelate. It is preferable to apply an agent or a combination of polyester and an organic titanium compound by coating.

The thermal transfer sheet of the present invention can be heated in the same way as a normal sheet by overlapping it with an image-receiving paper and heating it with a printer equipped with a dot-shaped heating means such as a thermal head. , pictures, photographs, etc., according to the input signal to the printer, and
In the portion where the end mark is formed, the end mark can be transferred and formed onto the image receiving paper.

Note that if the image signal in the end mark part is weak, the density may be low, or the density may vary depending on the size of the image signal, so when providing the end mark with a thermal transfer layer, use a dye with high heat sensitivity Please select something or
Alternatively, it is preferable to form the end mark with a heat-melting transfer layer that is not affected by the amount of energy.

〔Effect of the invention〕

In addition to the normal heat-sensitive transfer layer, the heat-sensitive transfer sheet of this invention has a part near the end of the sheet where an end mark can be transferred, so that the final frame of the heat-sensitive transfer sheet can be reached by simply transferring. Since it is possible to know that this is the case, or something close to it, just by looking at the hard copy, there is no need to increase the number of printer mechanisms or add processing heights during the production of thermal transfer sheets.

[Brief explanation of the drawing]

1 and 3 are plan views showing a heat-sensitive transfer sheet of the present invention, and FIG. 2 is a plan view showing an example of an end mark formed by transfer.

Claims (1)

[Claims] A heat-sensitive transfer sheet having a heat-sensitive transfer layer on a base sheet that melts the layer itself or transfers the dye in the layer by melting or sublimating due to heat, and has an end mark pattern near the end of the sheet. A heat-sensitive transfer sheet characterized by having a transferable portion.