JPH1134518A - Sheet to be thermally transferred - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet to be thermally transferred by which a favorable paper feed running property is obtained. SOLUTION: For this sheet 1 to be thermally transferred, on the major surface of a sheet-form base material 2, an acceptor layer 3 in order to accept a dye is formed, and the sheet 1 to be thermally transferred is fed by a paper feeding roller which is arranged on a printing device when an image is printed. For this sheet 1 to be thermally transferred, a static frictional factor between the sheets 1 to be thermally transferred is 0.15 or higher, and 0.48 or lower, and a dynamic fricitional factor between the sheets 1 to be heat-transferred is 0.32 or lower, and a static frictional factor with the paper feeding roller is 0.65 or higher and 1.0 or lower.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat transfer sheet to which a dye is thermally transferred from an ink ribbon or the like, and more particularly to a heat transfer sheet having good running properties.

[0002]

2. Description of the Related Art As a method of developing image information input to a video apparatus on photographic paper, a thermal transfer method using a sublimable dye or a hot-melt dye is used.

In this thermal transfer method, a thermal transfer sheet having a dye layer formed thereon and a heat-transfer sheet having a dye-receiving layer formed thereon (hereinafter referred to as photographic paper) are used.
The dye layer and the receiving layer are superimposed so as to face each other, and heat is applied in a dotted manner by a thermal head or the like in accordance with an image signal. As a result, the dye in the dye layer sublimates or melts and transfers to the receiving layer of the photographic paper, and an image appears on the photographic paper.

The use of the photographic paper on which the image is formed is, for example, a photograph, a white sticker, or a post card having a back surface with writeability, and the material and configuration of the photographic paper are selected according to these uses. You.

[0005] Such a photographic paper has, for example, a two-layer structure in which a receptor layer for receiving a dye is formed on a sheet-like substrate.

[0006] The receiving layer receives the image of the dye migrating from the ink ribbon, for example, a sublimable disperse dye, and maintains the formed image. As the material of the receiving layer, polyester resin, polystyrene resin, acrylonitrile-styrene copolymer, acrylonitrile-butadiene-styrene resin, cellulose resin, vinyl chloride resin, urethane resin and the like are used. In addition, a polyisocyanate may be added to the receiving layer in order to improve heat resistance.

[0007]

As a system for printing an image on photographic paper, various systems such as a chucking system and a swing system have been proposed.

However, in any of the methods, if the coefficient of friction between the printing papers is large, a plurality of photographic papers are simultaneously fed, that is, a double feeding phenomenon occurs, and if the friction between the paper feed roller and the photographic paper is small, the feeding is performed. There is a problem that paper failure occurs.

The present invention has been proposed in view of the conventional circumstances, and has as its object to provide a heat-transferable sheet which can obtain a good paper feed running property.

[0010]

The heat transfer sheet according to the present invention, which has been completed to achieve the above-mentioned object, has a receiving layer for receiving a dye formed on the main surface of a sheet-like substrate. That is, when an image is printed, paper is fed by a paper feed roller provided in the printer device.

In particular, the heat transfer sheet according to the present invention has a coefficient of static friction between the heat transfer sheets of 0.15 or more and 0.4 or less.
8 or less, and the coefficient of dynamic friction between the heat transfer sheets is 0.3
2 or less, and the coefficient of static friction with the paper feed roller is 0.6
It is not less than 5 and not more than 1.0.

In the heat transfer sheet according to the present invention configured as described above, the coefficient of static friction between the heat transfer sheets, the coefficient of dynamic friction, and the coefficient of static friction with the sheet feed roller are within the above-mentioned predetermined ranges. Therefore, the double feeding phenomenon and the paper feeding failure phenomenon can be suppressed as much as possible, and a good paper feeding traveling property can be obtained.

[0013]

Embodiments of the present invention will be described below in detail with reference to the drawings.

As shown in FIG. 1, a thermal transfer sheet 1 to which the present invention is applied has a receiving layer 3 for receiving a dye from a thermal transfer sheet formed on at least one principal surface 2a of a sheet-like substrate 2. Become.

The heat transfer sheet 1 is supplied to a printer such as a thermal printer so as to be superimposed on the ink ribbon. Then, as shown in FIG. 2, the heat transfer sheet 1 is fed by a feed roller 4 provided in the printer when printing an image. At this time, of the heat transfer sheets overlapped, one heat transfer sheet 1 is sent out by the feed roller 4, and the other heat transfer sheet 5 is separated from the heat transfer sheet 1 by the separation roller 6, and the heat transfer sheet 1 is separated from the heat transfer sheet 1. Sent in the opposite direction.

In particular, the heat transfer sheet 1 to which the present invention is applied
Means that the coefficient of static friction between the heat transfer sheets 1 and 5 is 0.15
As described above, the value is set to 0.48 or less.

Here, if the coefficient of static friction between the heat transfer sheets 1 and 5 is 0.15 or less, it is difficult to handle the heat transfer sheet in the tray of the printer device, that is, the handling is not preferable, and It collapses when stacking thermal transfer sheets. Further, when the sheets to be heat-transferred are manufactured, they are broken when stacked. Thus, the coefficient of static friction between the heat transfer sheets 1 and 5 is 0.1
If it is smaller than 5, handling and stacking stability will be poor.

On the other hand, if the coefficient of static friction between the heat transfer sheets 7 and 8 is larger than 0.48, as shown in FIG. It is not preferable because paper is fed.

In particular, the thermal transfer sheet 1 to which the present invention is applied has a dynamic friction coefficient between the thermal transfer sheets 1 and 5 of at least 0.32 in a state where at least a part of the sheets overlaps.

If the coefficient of kinetic friction between the heat transfer sheets 9 and 10 is greater than 0.32, the two heat transfer sheets 9 and 10 are separated by the feed roller 4 and the separation roller 6 as shown in FIG. The paper is not completely separated, but is partially overlapped. That is, a double feed phenomenon occurs. It should be noted that as the coefficient of kinetic friction between the heat transfer sheets is larger, the plurality of heat transfer sheets are fed in a stacked state without being separated.

Further, in the heat transfer sheet 1 to which the present invention is particularly applied, the coefficient of static friction with the paper feed roller 4 is 0.65.
As described above, the value is set to 1.0 or less.

If the coefficient of static friction with the feed roller 4 is smaller than 0.65, the transfer sheet is
The paper is not fed.

In the heat transfer sheet 1, the electric resistance of the surface 2b of the sheet-like substrate 2 opposite to the side on which the receiving layer 3 is formed is preferably 10 ¹⁰ Ω or less. This is because if the electric resistance is greater than 10 ¹⁰ Ω, a paper feed failure occurs due to electrostatic charging. In order to control the electrical resistance on the surface of the heat transfer sheet 1 as described above, it is preferable to perform an antistatic treatment on the surface 2b of the substrate 2 opposite to the side on which the receiving layer 3 is formed.

Further, the heat transfer sheet 1 preferably has a glossiness of the surface 3a of the receiving layer 3 of 80% or more from the viewpoint of running properties. This is because when the glossiness is smaller than 80%, the coefficient of friction between the heat transfer sheets becomes low when the back coat layer is formed on the surface 2b of the substrate 2 opposite to the side on which the receiving layer 3 is formed. This is because the control depends only on the surface properties of the back coat layer, and the control becomes difficult.

Further, in the heat transfer sheet 1, as shown in FIG. 5, when the curl height h of the base material 2 is high, that is, when the heat transfer sheet 1 is warped, the heat transfer sheet 1 is positioned from the plane L formed by the bottom of the substantially central portion. The height of the outermost peripheral portion 2a is 10 mm or less under an environment of a temperature of 20 ° C. and a humidity of 50%. This is the substrate 2
When the height h of the curl is larger than 10 mm in an environment of a temperature of 20 ° C. and a humidity of 50%, a running failure occurs.

The heat transfer sheet 1 to which the present invention having the above characteristics is applied is made of the following materials.

Examples of the sheet-shaped base material 2 include polyolefin-based and polystyrene-based synthetic paper, high-quality paper, art paper, coated paper, cast-coated paper, wallpaper, backing paper, synthetic resin or emulsion impregnated paper, and synthetic rubber. Paper such as latex-impregnated paper, paper with synthetic resin, paperboard, cellulose fiber paper, and plastic films or sheets made of various synthetic resins such as polyolefin, polyvinyl chloride, polyethylene terephthalate, polystyrene, polymethacrylate, and polycarbonate are used. Further, the substrate 2
For example, a white transparent film obtained by adding a white pigment or the like to the above synthetic resin, a foamed foamed film, or the like may be used.

The thickness of the substrate 2 may be arbitrarily set, for example, generally 10 μm to 200 μm. When the adhesion of the substrate 2 to the receptor layer 3 formed on the surface is poor, it is preferable to apply a primer treatment or a corona discharge treatment to the surface.

The substrate 2 may be a laminate formed by combining a plurality of the above-mentioned substrates. As a typical base material of the laminate, for example, a combination of cellulose fiber paper and synthetic paper, or a combination of cellulose fiber paper and a plastic film and the like can be mentioned.

The receiving layer 3 is mainly made of a thermoplastic resin. Specifically, polyester resins, polycarbonate resins, vinyl chloride copolymers such as polyvinyl chloride and vinyl chloride-vinyl acetate copolymer, polyvinyl acetal resins, polyvinyl butyral resins, polyamide resins, vinyl acetate resins, polyurethane resins, polystyrene Resin, A
S resin, ABS resin, cellulose ester resin, polyvinyl alcohol and the like can be used, and these may be used alone or in combination of two or more.
Above all, it is preferable to use a mixture of a polyester resin and a cellulose ester resin from the viewpoint of improving sensitivity, image storability, writability, and sebum resistance.

A sensitizer may be added to the receiving layer 3 for the purpose of increasing the dyeing ability of the dye and improving the light fastness. As the sensitizer, it is necessary to be compatible with the above-mentioned thermoplastic resin, and for example, esters, ethers, hydrocarbon compounds and the like are used. When these sensitizers are added to the resin, they are compatible with the resin to form an amorphous state. Thereby, it is considered that the diffusion of the dye is promoted and the dye penetrates into the receiving layer. The sensitizer may have a melting point of about -50 ° C to 150 ° C, and is used in a liquid or solid state.

Specifically, the sensitizer esters include phthalic acid esters such as dimethyl phthalate, diethyl phthalate, dioctyl phthalate, dicyclohexyl phthalate and diphenyl phthalate, dioctyl adipate, dioctyl sepate, and dicyclohexyl azelate. Aliphatic dibasic acid esters such as, triphenyl phosphate, tricyclohexyl phosphate, phosphate esters such as triethyl phosphate, further dimethyl isophthalate, diethyl isophthalate,
Isophthalic acid esters such as dicyclohexyl isophthalate; and higher fatty acid esters such as butyl stearate and cyclohexyl laurate. In addition, silicates, boron and the like are also used.

As ethers to be used as sensitizers, there are diphenyl ether, dicyclohexyl ether, methyl p-ethoxybenzoate and the like.

Examples of the hydrocarbon compound serving as a sensitizer include camphor and low molecular weight polystyrene. In addition, phenols such as p-phenylphenol and o-phenylphenol, and N-ethyltoluenesulfonic acid amides, in which a polar group is introduced into a hydrocarbon compound, can also be used.

The receiving layer 3 improves the whiteness of the receiving layer, thereby increasing the sharpness of the transferred image and imparting writability to the surface of the photographic paper. For the purpose of prevention, a fluorescent whitening agent or a white pigment may be added. As the fluorescent whitening agent, any commercially available fluorescent whitening agent such as Ubitex OB (trade name, manufactured by Ciba Geigy) can be used.

Further, an antistatic agent may be internally added or applied to the receiving layer 3 in order to prevent the generation of static electricity during the paper feeding travel.

As the antistatic agent, a surfactant or the like is used. The surfactant is a cationic static surfactant,
Anionic surfactants, zwitterionic surfactants and nonionic surfactants can all be used. Examples of the cationic surfactant include quaternary ammonium salts and polyamine derivatives, and examples of the anionic surfactant include alkylbenzene sulfonate and alkyl sulfate sodium salt. These antistatic agents may be contained in the receiving layer 3 or may be applied to the surface of the receiving layer 3 by coating or the like.

Further, in addition to the above, a plasticizer, an ultraviolet absorber, an antioxidant and the like can be appropriately compounded in the receiving layer 3.

The heat transfer sheet 2 to which the present invention is applied
0, as shown in FIG.
The receiving layer 22 may be formed on the surface a, and a back coat layer 23 made of a lubricant may be provided on the surface 21b opposite to the side on which the receiving layer 22 is formed.

Here, examples of the material of the back coat layer 23 include an acrylic resin, a polyester resin, a vinyl chloride resin, a styrene-maleic acid copolymer resin, a vinyl acetate resin, an acrylonitrile-styrene copolymer resin, and the like. It should be noted that a filler may be added to the back coat layer 23 to improve the paper feed running property. Examples of the filler material include an organic filler such as a fluororesin, a polyamide resin, a styrene resin, a phenol resin, a polyimide resin, a melamine resin, and an epoxy resin, and an inorganic filler such as calcium carbonate, silica, clay, titanium oxide, and zinc oxide. Both can be used. However, organic fillers are preferred over inorganic fillers in that they are soft.

The back coat layer 23 may contain a release agent compatible with these resins, for example, silicone or a surfactant. For example, when the heat transfer sheet is set upside down in a printer by mistake, if the back coat layer 23 does not have releasability, the dye is fused to the back coat layer 23 to cause paper jam and damage the printer. Cause. When a release agent is added to the back coat layer 23, paper jam due to such fusion of the dye is prevented. However, among the above resins, acrylic resin, styrene-maleic acid copolymer resin and vinyl acetate resin have relatively low releasability, so that it is useful to add a release agent.

The heat transfer sheet 3 to which the present invention is applied
As shown in FIG. 7, the number 0 may include a seal portion 31 and a separate portion 32.

The sealing portion 31 has a receiving layer 34 formed on one main surface 33a of the sheet-like base material 33, and is formed on one main surface 33b of the base material 33 opposite to the side on which the receiving layer 34 is formed. An adhesive layer 35 is formed.

The separate part 32 includes a separate base material 36.
A release layer 37 is formed on one main surface 36a of the
A back coat layer 38 is formed on one main surface 36b of the separate base material 36 on the side opposite to the side on which is formed.

The heat transfer sheet 30 is configured such that the seal portion 31 and the separate portion 32 configured as described above are adhered releasably.

Here, the release layer 37 is formed by applying a material having a releasability to the adhesive of the adhesive layer 35, for example, silicone or the like.

The sheet-like base material 33, the separate base material 36,
The receiving layer 34 and the back coat layer 38 can be formed using the same materials as those described above.

[0048]

Embodiments of the present invention will be described below based on experimental results.

Example 1 First, foamed polyethylene terephthalate (manufactured by Toyobo Co., Ltd .; trade name: Krispar) having a thickness of 188 μm was prepared as a substrate. Next, the following coating material for a receiving layer was applied on the substrate so as to have a dry film thickness of 10 μm.
Curing was performed for a minute to form a receiving layer.

<Composition of Receptive Layer Coating> 100 parts by weight of polyester (Byron 200 manufactured by Toyobo Co., Ltd.) 5 parts by weight of silicone (KF393 manufactured by Shin-Etsu Chemical Co., Ltd.) 200 parts by weight of methyl ethyl ketone 200 parts by weight of toluene On the surface opposite to the side on which the receiving layer was formed, a paint for a back coat layer shown below was applied to a thickness of 1 μm.
m and cured at a temperature of 120 ° C. for 1 minute to form a back coat layer.

<Composition of paint for back coat layer> Styrene-acrylonitrile (Styrac AS, manufactured by Asahi Kasei Corporation) 100 parts by weight Antistatic agent (Electro-Stripper PC manufactured by Kao Corporation) 10 parts by weight Silicon powder (Trefill E, manufactured by Shin-Etsu Chemical Co., Ltd.) 10 parts by weight Methyl ethyl ketone 200 parts by weight Toluene 200 parts by weight As described above, the receiving layer and the back coat layer were formed on the base material, and a photographic paper was produced.

Example 2 A photographic paper was prepared in the same manner as in Example 1 except that the coating composition for the receiving layer shown below was used.

<Composition of coating for receiving layer> 100 parts by weight of polyester (Byron 600 manufactured by Toyobo Co., Ltd.) 5 parts by weight of silicone (KF393 manufactured by Shin-Etsu Chemical Co., Ltd.) 200 parts by weight of methyl ethyl ketone 200 parts by weight of toluene

Example 3 White polyethylene terephthalate PET having a thickness of 188 μm was used as a base material, a paint having the same composition as in Example 2 was used as a paint for a receiving layer, and a paint having the following composition was used as a paint for a back coat layer. A photographic paper was produced in the same manner as in Example 1 except that the photographic paper was used.

<Composition of paint for back coat layer> Acrylic resin (BR85, manufactured by Mitsubishi Rayon Co., Ltd.) 100 parts by weight Antistatic agent (Electro Stripper PC, manufactured by Kao Corporation) 10 parts by weight Methyl ethyl ketone 200 parts by weight Toluene 200 parts by weight

Example 4 A photographic paper was prepared in the same manner as in Example 1 except that a foamed polypropylene having a thickness of 150 μm was used as a base material, and a coating material for a receiving layer having the following composition was used.

<Composition of Receptive Layer Paint> 100 parts by weight of vinyl acetate (C5 manufactured by Sekisui Chemical Co., Ltd.) 5 parts by weight of silicone (KF393 manufactured by Shin-Etsu Chemical Co., Ltd.) 200 parts by weight of methyl ethyl ketone 200 parts by weight of toluene

Example 5 Except that a foamed polyethylene terephthalate having a thickness of 188 μm was used as the base material, the same coating material as in Example 3 was used as the coating material for the back coat layer, and the coating material for the receiving layer had the following composition. A photographic paper was produced in the same manner as in Example 1.

<Composition of coating for receiving layer> 100 parts by weight of vinyl chloride-vinyl acetate copolymer (# 1000D manufactured by Denki Kagaku Kogyo KK) 5 parts by weight of silicone (KF393 manufactured by Shin-Etsu Chemical Co., Ltd.) 5 parts by weight of methyl ethyl ketone 200 parts by weight of toluene 200 parts by weight of toluene

Comparative Example 1 A substrate similar to that of Example 3 was used as the base material, a coating similar to that of Example 1 was used as the coating for the receiving layer, and a coating having the following composition was used as the coating for the backcoat layer. except,
A photographic paper was produced in the same manner as in Example 1.

<Coating for Backcoat Layer> Acrylic resin (BR85, manufactured by Mitsubishi Rayon Co.) 100 parts by weight Antistatic agent (Electro Stripper PC, manufactured by Kao Corporation) 10 parts by weight Talc (SS, manufactured by Nippon Talc Co.) 50 parts by weight Methyl ethyl ketone 200 Parts by weight toluene 200 parts by weight

Comparative Example 2 A substrate similar to that of Example 3 was used as a substrate, a coating similar to that of Example 2 was used as a coating for a receiving layer, and a coating having the following composition was used as a coating for a backcoat layer. except,
A photographic paper was produced in the same manner as in Example 1.

<Coating for Back Coat Layer> Styrene (Denka Styrol GP QP-3 manufactured by Denki Kagaku Kogyo Co., Ltd.) 100 parts by weight Titanium oxide (R-GL manufactured by Sakai Chemical Co., Ltd.) 50 parts by weight Antistatic agent (Kao Corporation electro stripper) PC) 10 parts by weight Methyl ethyl ketone 200 parts by weight Toluene 200 parts by weight

COMPARATIVE EXAMPLE 3 A base material similar to that of Example 3 was used, a receiving layer coating material similar to that of Example 2 was used, and a backcoat layer coating material similar to that of Comparative Example 1 was used. Except for
A photographic paper was produced in the same manner as in Example 1.

COMPARATIVE EXAMPLE 4 A base material similar to that of Example 3 was used, a receiving layer coating material similar to that of Example 4 was used, and a backcoat layer coating material similar to that of Comparative Example 2 was used. Except for
A photographic paper was produced in the same manner as in Example 1.

COMPARATIVE EXAMPLE 5 The same base material as in Example 3 was used, the receiving layer paint was the same as in Example 4, and the back coat layer paint was the same as in Comparative Example 1. Except for
A photographic paper was produced in the same manner as in Example 1.

COMPARATIVE EXAMPLE 6 A substrate similar to that of Example 4 was used as the base material, a coating similar to that of Example 5 was used as the coating for the receiving layer, and a coating similar to that of Comparative Example 2 was used as the coating for the backcoat layer. Except for
A photographic paper was produced in the same manner as in Example 1.

Comparative Example 7 A substrate similar to that of Example 3 was used as a substrate, a coating similar to that of Example 5 was used as a coating for a receiving layer, and a coating having the following composition was used as a coating for a back coat layer. except,
A photographic paper was produced in the same manner as in Example 1.

<Composition of Back Coat Layer Coating Material> Styrene (Denka Styrol GP QP-3 manufactured by Denki Kagaku Kogyo Co., Ltd.) 100 parts by weight Methyl ethyl ketone 200 parts by weight Toluene 200 parts by weight Examples 1 to 5 prepared as described above. And Comparative Example 1
For each of the photographic papers of Comparative Example 7 to Comparative Example 7, the static friction coefficient between the photographic papers, the dynamic friction coefficient, and the static friction coefficient between the paper feed roller and the photographic paper were measured as described below.

Examples 1 to 5 and Comparative Examples 1 to
A running test and a handling test as described below were performed on each of the photographic papers of Comparative Example 7.

Further, Examples 1 to 5 and Comparative Example 1
The electrical resistance and curl of each of the photographic papers of Comparative Example 7 to Comparative Example 7 were measured as described below.

(1) Measurement of Coefficient of Friction First, the photographic papers produced in Examples and Comparative Examples were each
I prepared it. Then, the receiving layer surface of one of the photographic papers was turned upside down and wound around an ASTM flat indenter. Next, under the ASTM flat indenter, the back surface of the other photographic paper, that is, the back coat layer surface was arranged so as to face the ASTM flat indenter. Then, using HEDON-14DR (manufactured by Shinto Kagaku), the load was 1000 g, and the speed was 20.
0mm / sec, applicable standard ASTM D as jig
The friction coefficient between photographic papers was measured under the measurement conditions using an 1894 ASTM flat indenter.

The measurement of the coefficient of friction as described above was similarly carried out for each two photographic papers produced in the other examples and comparative examples.

Here, in the friction measurement between the paper feed roll and the printing paper, HEIDON-1 was measured under the same measurement conditions as described above.
It was measured using 4DR. The above results are shown in Tables 1 and 2.

(2) Method of running test First, the photographic papers produced in the Examples and Comparative Examples were respectively
00 sheets were prepared. Then, using an ink ribbon (UPC-1010: manufactured by Sony Corporation) composed of each dye of yellow, magenta, and cyan, a sublimation transfer printer UP-120 is used.
Using 0 (manufactured by Sony Corporation), the number of paper feeding errors when printing with a gradation pattern was measured.

The above-described measurement of the sheet feeding error was performed in the same manner using 100 sheets of photographic paper produced in the other Examples and Comparative Examples.

The above results are shown in Tables 1 and 2. In Tables 1 and 2, ○ indicates that the running property was good, X indicates that the running property was poor, and △ indicates that the running property was intermediate.

(3) Method of Handling Test The measurement was carried out under two conditions, ie, measurement condition A and measurement condition B, as measurement conditions of the handling test. Under either condition, 100 sheets of photographic paper prepared in each example and comparative example were prepared.

<Measurement Condition A> 100 sheets of prepared photographic paper were put together at an inclination of 30 °, and the manner in which the photographic paper fell was observed. The results are shown in Tables 1 and 2. Here, when the pieces fell apart one by one, it was evaluated as ○, when two or three sheets overlapped and fell, Δ was evaluated, and when they fell in one lump, as ×.

<Measurement Condition B> A state in which 100 sheets of the prepared photographic paper were conveyed together at a speed of 6 m / h on a belt conveyor was observed. The results are shown in Tables 1 and 2. Here, the case where the 100 sheets of photographic paper that were put together did not collapse was evaluated as ○, and the case where it collapsed was evaluated as x.

(4) Method of Measuring Electric Resistance As a method of measuring electric resistance, Megastar M
ODEL HT-301 (SHISEIDO ELEC
TROSTATIC LTD) at a temperature of 25
Each of the photographic papers prepared in Examples and Comparative Examples was allowed to stand for 1 day in an environment at a temperature of 60 ° C. and a humidity of 60%, and then measured under an environment of a temperature of 25 ° C. and a humidity of 60%.

The results are shown in Tables 1 and 2.

(5) Method of measuring curl As a method of measuring curl, each of the photographic papers produced in Examples and Comparative Examples was left for a certain period of time in an environment of a temperature of 20 ° C. and a humidity of 50%, and the curled portion was examined. The maximum height value was measured. The results are shown in Tables 1 and 2.

(6) Gloss Measurement Method Gloss was measured by using a digital variable-angle gloss meter VG-1 (manufactured by Nippon Denshoku Industries Co., Ltd.) for each of the photographic papers produced in Examples and Comparative Examples. The gloss was measured at an angle of 60 °. The results are shown in Tables 1 and 2.

[0085]

[Table 1]

[0086]

[Table 2]

From the results shown in Tables 1 and 2, the heat transfer sheets of Examples 1 to 5 in which the static friction coefficient between the heat transfer sheets is 0.15 or more and 0.48 or less are the same as those of the heat transfer sheets. It was found that the heat transfer sheets of Comparative Examples 1, 2, 4, and 5 having a coefficient of static friction outside the above-mentioned range had excellent paper feedability and excellent handling characteristics. From this, it can be said that the coefficient of static friction between the heat transfer sheets is preferably 0.15 or more and 0.48 or less.

The heat transfer sheets of Examples 1 to 5 in which the coefficient of dynamic friction between the heat transfer sheets is 0.32 or less are the same as those of Comparative Examples 2 and 3 in which the coefficient of dynamic friction between the heat transfer sheets is 0.32 or more. It was found that, compared to the heat-transferred sheet of Comparative Example 5, the sheet-feeding runnability was excellent and the handling characteristics were also excellent. From this, it can be said that the coefficient of dynamic friction between the heat transfer sheets is preferably 0.32 or less.

In the first to fifth embodiments, the coefficient of static friction between the sheet feeding roller and the sheet to be transferred is 0.65 or more and 1.0 or less.
The heat-transferred sheet of Example 5 was found to be excellent in the paper feed running property and the handling characteristics as compared with Comparative Example 3 in which the coefficient of static friction with the paper feed roller was out of the above range. From this, it can be said that the coefficient of static friction between the sheet feeding roller and the heat transfer sheet is preferably 0.65 or more and 1.0 or less.

Further, the heat transfer sheets of Examples 1 to 5 having an electric resistance of 10 ¹⁰ or less are superior in the feedability and the handling characteristics to Comparative Example 7 in which the electric resistance is out of the above range. Also turned out to be excellent. From this, it can be said that the electric resistance is preferably 10 ¹⁰ or less.

The curl height is 20 ° C. and 50% humidity.
%, The heat transfer sheets of Examples 1 to 5 having a curl height of 10 mm or less are superior to the heat transfer sheets of Comparative Example 7 having a curl height of 10 mm or more in terms of paper feedability and handling characteristics. It turned out to be excellent. From this, the curl height is 10 m at a temperature of 20 ° C. and a humidity of 50%.
It can be said that m is preferable.

Further, in Examples 1 to 5 in which the glossiness was 80% or more, Comparative Examples 1 to 5 in which the glossiness was 80% or less were used.
It was found that the sheet feedability was excellent and the handling characteristics were also excellent as compared with Comparative Example 7. In particular, in Comparative Examples 1 to 3 having extremely low gloss, it was found that the handling characteristics were reduced. From this, the glossiness is 80
% Is preferable.

[0093]

As described above in detail, according to the heat transfer sheet according to the present invention, the coefficient of static friction between the heat transfer sheets is 0.15 or more and 0.48 or less, and the heat transfer sheet Has a dynamic friction coefficient of 0.32 or less,
Furthermore, the coefficient of static friction with the paper feed roller is 0.65 or more,
By setting the ratio to 1.0 or less, phenomena of double feeding and paper feeding failure can be suppressed as much as possible, good paper feeding traveling property can be obtained, and a high quality heat transfer sheet can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating an example of a heat transfer sheet to which the present invention is applied.

FIG. 2 is a schematic diagram illustrating a state in which a heat transfer sheet is fed by a feed roller.

FIG. 3 is a schematic diagram showing an example of a double feeding phenomenon in which heat transfer sheets are fed while being overlapped.

FIG. 4 is a schematic diagram illustrating another example of a double feeding phenomenon in which a sheet to be thermally transferred is fed while being overlapped.

FIG. 5 is a schematic view showing a curl of a heat transfer sheet.

FIG. 6 is a cross-sectional view illustrating another example of a heat transfer sheet to which the present invention is applied.

FIG. 7 is a cross-sectional view illustrating another example of a heat transfer sheet to which the present invention is applied.

[Explanation of symbols]

1, 5, 20, 30 Heat transfer sheet, 2 base material, 3
Receiving layer, 4 paper feed rollers

Claims (4)

[Claims] 1. A heat transfer sheet which is formed by forming a receptor layer for receiving a dye on a sheet-like substrate, and which is fed by a feed roller provided in a printer device when printing an image. Wherein the coefficient of static friction between the heat transfer sheets is 0.15 or more;
48 or less, the coefficient of kinetic friction between the heat transfer sheets is 0.32 or less, the coefficient of static friction with the paper feed roller is 0.65 or more,
A heat-transferable sheet, wherein the ratio is 1.0 or less. 2. The heat transfer sheet according to claim 1, wherein an electrical resistance of a surface of the substrate opposite to the surface on which the receiving layer is formed is 10 ¹⁰ Ω or less. 3. The heat transfer sheet according to claim 1, wherein the glossiness of the surface on which the receiving layer is formed is 80% or more. 4. The method according to claim 1, wherein said substrate has a curl height of 20 ° C.
2. The heat transfer sheet according to claim 1, wherein the thickness of the heat transfer sheet is 10 mm or less in an environment of 50 [deg.] C. and 50% humidity.