JPH0973177A - Electrostatic recording paper for sublimation printing - Google Patents

Abstract

(57) [Summary] [Structure] The electrostatic recording paper for sublimation printing of the present invention is provided with a hydrophilic resin layer on a conductive base paper, or further has a moisture resistance on the hydrophilic resin layer. An improvement layer is provided, or a dielectric layer is provided on a conductive base paper, and a hydrophilic resin layer is provided on the dielectric layer, or on the hydrophilic resin layer. A moisture resistance improving layer is provided. The electrostatic recording paper for sublimation printing of the present invention can obtain a high image density and a high transfer rate when printing on a cloth,
Further, by laminating a humidity resistance improving layer, it is possible to prevent deterioration with time due to humidity during charging and development, and it is possible to improve the imageability. By using it for textile printing transfer to a cloth using an ion printer. Further, it is possible to increase the image density on the printing cloth, form an image with a sharp contrast on the cloth and have an impact, and it is possible to manufacture a printing cloth excellent in design.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrostatic recording paper for sublimation printing, which is excellent in the ability to prevent dye diffusion in the direction of the base paper and is excellent in transfer printing on a fabric.

More specifically, an electrostatic latent image pattern formed on an electrostatic recording paper by an ion head is developed by using a wet developer having a sublimation printing ability, and the obtained image on the electrostatic recording paper is a cloth. The present invention relates to an electrostatic recording paper for an ion printer capable of forming a sublimation transfer image having a clear shade on a fabric by thermal sublimation transfer.

[0003]

2. Description of the Related Art Conventionally, a sublimation printing transfer method has been known as a method for forming a pattern or pattern on a cloth. Recently, for example, in JP-A-3-18866, an electrostatic latent image is formed on an electrostatic recording paper by an electrostatic plotter / facsimile, and developed by a wet developer in which a dye having a sublimation printing ability is dispersed / dissolved, It has been proposed to produce transfer printing paper.

However, in these electrostatic latent image forming methods, the image obtained is a pseudo gradation, which is inferior in the expression of halftone, and there is a problem in the image characteristics especially in the highlight portion. As a result, the characteristics of gravure printing used in the production of textile transfer paper for polyester fabrics cannot be fully exerted, and the design is particularly high, resulting in inferior expression of photographic patterns and blurring that are commercially favored. Has become.

Therefore, the inventors of the present invention form an electrostatic latent image on an electrostatic recording paper by using an ion printer and develop the electrostatic latent image with a wet developer having a sublimation printing property to produce a printing paper. It was filed with the applicant that the problem of image expressivity could be solved by using it for printing on polyester fabric.

However, the conventional electrostatic recording paper has been developed for the electrostatic plotter, and the wet developer used is
Usually, a pigment is used as a colorant, and therefore, the conventional electrostatic recording paper has no measures for dyeability and heat diffusion prevention of a sublimation dye. for that reason,
When an electrostatic latent image formed on a conventional electrostatic recording paper is developed using a developer for sublimation printing, and the resulting image of sublimable dye is transferred to a fabric by thermal transfer, the dye is only in the fabric direction. However, there is a problem that thermal diffusion also takes place in the direction of the dielectric layer on the electrostatic recording paper, making it difficult to increase the image density on the cloth.

[0007]

DISCLOSURE OF THE INVENTION The present invention provides a printing paper obtained by developing an electrostatic latent image pattern formed on an electrostatic recording paper by an ion head using a wet developer having a sublimation printing ability. An object of the present invention is to provide an electrostatic recording paper for sublimation textile printing, which is used when a sublimation transfer image is formed on a cloth by heating the same together with the cloth and can achieve a high density sublimation transfer image.

[0008]

The first electrostatic recording paper for sublimation printing of the present invention is characterized in that a hydrophilic resin layer is provided on a conductive base paper.

The second electrostatic recording paper for sublimation printing of the present invention is
A hydrophilic resin layer is provided on a conductive base paper, and a moisture resistance improving layer is provided on the hydrophilic resin layer.

The third electrostatic recording paper for sublimation printing of the present invention is
A dielectric layer is provided on a conductive base paper, and a hydrophilic resin layer is provided on the dielectric layer.

The fourth electrostatic recording paper for sublimation printing of the present invention is
A dielectric layer and a hydrophilic resin layer are sequentially provided on a conductive base paper, and a moisture resistance improving layer is provided on the hydrophilic resin layer.

The electrostatic recording paper for sublimation printing of the present invention will be described below.

First, the first electrostatic recording paper for sublimation printing of the present invention comprises a base paper having conductivity and a hydrophilic resin layer laminated on the base paper.

As the conductive base paper, an inorganic salt such as sodium chloride, a cationic polyelectrolyte such as polyvinylbenzyltrimethylammonium chloride, or an anionic polyelectrolyte, a surfactant, or zinc oxide, Impregnated or coated with a metal oxide semiconductor powder such as zinc oxide that has been subjected to conductivity treatment, and has a surface resistance of 10 ⁵ to 10 ¹¹ Ω.
The above-mentioned paper, plastic film, cloth, etc. are used, but it is necessary that they do not cause problems such as heat shrinkage due to heating under sublimation transfer conditions.

The hydrophilic resin layer will be described. The present invention is based on the fact that the hydrophilic resin has an excellent sublimation dye diffusion-preventing property, but since the electrostatic recording paper of the present invention is used for sublimation printing, it has heat resistance and a fabric. It is necessary that the resin has no fusing effect.

As such a hydrophilic resin, natural polymers and their derivatives can be used, and proteins such as gelatin, methyl (meth) acrylate-grafted gelatin, ethyl (meth) acrylate-grafted gelatin, (meth) are used. Butyl acrylate-grafted gelatin, gelatin nitrate, casein, soybean protein, yeast protein, bacterial protein, etc. Starch, that is, raw starch, α-starch, oxidized starch, esterified starch, etherified starch, sex starch, dextrin, etc. ,
Examples thereof include cellulose derivatives, that is, methyl cellulose, ethyl cellulose, carboxymethyl cellulose, nitrocellulose and the like, and gums, that is, gum arabic, guar gum, locust bean gum and the like. Further, as a resin having a hydroxyl group which is a synthetic polymer, an acrylic resin is a poly [(meth) acrylic acid hydroxyethyl], a polyvinyl alcohol or the like is a resin having a carboxyl group, and an acrylic resin is a [poly [(meth) acrylic acid]. As a resin having an amide group, acrylamide resin is poly (acrylamide), poly (isopropylamide), etc.
Moreover, polyamide etc. are mentioned. Moreover, the copolymer resin of the monomer which comprises these resins and another resin monomer is mentioned. Further, these resins can be mixed and used.

Preferred resins include gelatin, polyvinyl alcohol having a high degree of saponification, acrylic acid, polyamide and the like.

As a method for forming the hydrophilic resin layer, the hydrophilic resin is dissolved in water, alcohol, or a mixed solvent thereof to prepare a solution having a solid content concentration of 1% by weight to 25% by weight, and a gel at a temperature of about 40 ° C. or higher. Using a coating machine such as an air knife coater, roll coater, blade coater at the temperature above
It is coated on a base paper having conductivity, and the coating amount after drying is 0.
5 g / m ^{2 to} 30 g / m ² , preferably 1 g / m ² to 1
It is good to set it to 0 g / m ² . If the coating amount is less than 0.5 g / m ² , the density of the high density image in the gradation image formed on the fabric after printing tends to be insufficient, and if it exceeds 30 g / m ² , the image is formed on the fabric after printing. In addition, the gradation characteristics of the gradation image tend to deteriorate, which is not preferable.

The second electrostatic recording paper for sublimation printing of the present invention is
It is intended to improve the moisture resistance and the like of the first electrostatic recording paper for sublimation printing, wherein a moisture resistance improving layer is provided on the hydrophilic resin layer.

The moisture resistance improving layer also needs to be a resin which is excellent in heat resistance and does not have a fusing action with the fabric, and preferably does not have a dyeing seat for dyeing a sublimation dye, and , The melting point or softening point of the resin must be sufficiently higher than the sublimation temperature of the dye, for example, acrylic ester resin, methacrylic ester resin, butyral resin, silicone resin, styrene resin,
Examples thereof include hydrophobic resins such as acrylonitrile resin and polycarbonate resin, and thermosetting resins such as phenol resin, furan resin, xylene / formaldehyde resin, epoxy resin and melamine resin. Further, a mixture of these resins, a copolymer or the like can also be used.

Concretely, as the acrylic resin, "Dianal BR Resin" manufactured by Mitsubishi Rayon Co., Ltd., "Parapet""Paragrass""Yumoglass" manufactured by Kyowa Gas Industrial Chemical Co., Ltd. , AS resin,
Hitachi Chemical Co., Ltd.'s "Vitax""Bifunen", Mitsui Toatsu Chemicals'"LilacA", Mitsubishi Monsanto Kasei's "Sunrex", Denki Kagaku Co., Ltd. "DENKA AS" manufactured by Idemitsu Petrochemical Co., Ltd.
"Topolex" manufactured by Mitsui Toatsu Chemical Co., Ltd., "Ulimate" manufactured by Mitsubishi Monsanto Kasei Kogyo Co., Ltd., "Denkastyrol" manufactured by Denki Kagaku Kogyo Co., Ltd., and Idemitsu Petrochemical Co., Ltd. ) "Taflon" manufactured by Teijin Kasei Co., Ltd., "Panlite", and the like.

The moisture resistance improving layer uses a resin as a dispersion medium such as an aromatic hydrocarbon such as toluene and xylene, a ketone such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, an ester such as ethyl acetate and methyl acetate, propanol and butanol. Solvents such as alcohols, etc., or mixed solvents thereof are used, and the solid content concentration is 5 wt% to
It is applied and formed as a solution of 50% by weight, preferably 8% by weight to 40% by weight.

As a coating method, a coating machine such as an air knife coater, a roll coater or a blade coater is used to coat the hydrophilic resin layer. The coating amount of the moisture resistance improving layer varies depending on the film thickness of the hydrophilic resin layer, capacitance, etc., but is usually 0.1 g / m ^{2 to} 20 g / m ² , preferably 0.5 g / m ^2. It is good to set it to about 5 g / m ² . 0.1
When it is less than g / m ² , uniform coating is difficult, the moisture resistance is insufficient, and the image density on the cloth after printing tends to deteriorate with time. Further, if the coating amount exceeds 20 g / m ² , gradation characteristics in the gradation image tend to deteriorate, which is not preferable.

The third electrostatic recording paper for sublimation printing of the present invention comprises a conductive base paper, a dielectric layer provided on the base paper, and a hydrophilic resin layer provided on the dielectric layer. is there.

As the dielectric layer, for example, an acrylic ester resin, a methacrylic ester resin, a butyral resin, a silicone resin, a styrene resin, an acrylonitrile resin, a polycarbonate resin, or another hydrophobic resin on a conductive base paper, acrylic acid. Examples include resins, acrylonitrile resins, polyamide resins, polyvinyl alcohol resins, hydrophilic resins such as gelatin, phenol resins, furan resins, xylene-formaldehyde resins, epoxy resins, and thermosetting resins such as melamine resins. Further, a resin such as a mixture of these resins or a copolymer is used, and it is formed by the same coating method as the above-mentioned moisture resistance improving layer.

The coating amount of the dielectric layer after drying is 0.5 g /
m ^{2 to} 30 g / m ² , preferably 1 g / m ^{2 to} 10 g /
m ² is good. When the coating amount is less than 0.5 g / m ² , the density of the high density portion image in the gradation image formed on the fabric after printing tends to be insufficient, and 30
If it exceeds g / m ² , the gradation characteristics of the gradation image formed on the fabric after printing tend to deteriorate, which is not preferable.

Then, a hydrophilic resin layer is formed on the dielectric layer in the same manner as the hydrophilic resin layer in the first electrostatic recording paper for sublimation printing described above.

This hydrophilic resin layer is usually 0.01 g / m ^{2 though it} varies depending on the film thickness of the dielectric layer, the electrostatic capacity and the like.
To 20 g / m ^2, preferably 0.01 g / m ² to 10 g
/ M ² is recommended. When it is less than 0.01 g / m ² ,
Uniform application becomes difficult, and the density of the high density image in the gradation image formed on the fabric after printing tends to be insufficient, and when it exceeds 20 g / m ² , the gradation image formed on the fabric after printing tends to be insufficient. It is not preferable because the gradation characteristics tend to deteriorate.

The fourth electrostatic recording paper for sublimation printing of the present invention is
A third moisture resistance improving layer is further provided on the hydrophilic resin layer for the purpose of improving the moisture resistance of the electrostatic recording paper for sublimation printing.

The moisture resistance improving layer can be formed of the same resin as the moisture resistance improving layer of the second electrostatic recording paper for sublimation printing described above, and is formed by the same coating method.

The coating amount of the moisture resistance improving layer varies depending on the film thickness of the dielectric layer and the hydrophilic resin layer, the capacitance, etc., but is usually 0.1 g / m ^{2 to} 20 g / m ² , and preferably or equal to ^{0.5g / m 2 ~5g / m 2} . 0.1g /
If it is less than m ² , uniform application is difficult, the moisture resistance is insufficient, and the image density on the cloth after printing tends to deteriorate with time. Further, if the coating amount exceeds 20 g / m ² , gradation characteristics in the gradation image tend to deteriorate, which is not preferable.

In the above-mentioned third and fourth electrostatic recording papers for sublimation printing, the dielectric layer formed on the conductive base paper is prepared by, for example, the following method. .

The basis weight on the surface of the quality paper of 55 g / m ^2, quaternary ammonium salts polymer (Sanyo Kasei Co., Ltd., trade name CHEMISTAT 6300), coated amount after drying 3 g / m ²
Gravure coater is applied by a gravure reverse method so that the coating amount after drying is 2 g / m ² on the back surface to form a conductive layer.
Next, ・ Toluene ・ ・ 66 parts by weight ・ Methyl methacrylate / ethyl acrylate copolymer resin (copolymerization ratio 1/1, weight average molecular weight 150,000) ・ ・ 8 parts by weight ・ Methyl methacrylate / butyl methacrylate copolymer Resin (copolymerization ratio 1/1, weight average molecular weight 150,000) ··· 8 parts by weight · Calcium carbonate (particle size 1000 nm) ··· 16 parts by weight of the dispersion liquid having a dry coating amount on the conductive paper surface. 4 g
/ M ² and composed manner, applied to form a dielectric layer, and an electrostatic recording paper.

Such a laminate is commercially available as electrostatic recording paper, for example, "Slever-S544C" manufactured by Sakurai Co., Ltd.
O, Slever-S536CO, Slever-S636CO, S
-542CO, S-624CO, S-642CO, S-
524CO or the like may be used.

A dielectric layer or a hydrophilic resin layer in the present invention,
If necessary, a dispersant, a defoaming agent, a leveling agent, an antiblocking agent, a viscosity modifier, etc. may be added to the moisture resistance improving layer.

The surface resistance values of the first to fourth electrostatic recording papers for sublimation printing according to the present invention are the electric resistance values specified by ASTM D257 and are 1 × 10 ¹⁵ Ω · cm to 1 × 10 ¹⁷ Ω · c.
m (65% humidity, 25 ° C.).

The electrostatic recording paper for sublimation printing of the present invention may be melted or diffused by heat using an ion printer, but as a sublimable dye, for example, Japanese Patent Application No.
With a developer containing the sublimable dye described in 202093 as a colorant, a desired pattern or pattern is formed,
This is used as a printing paper for heat transfer together with a cloth or the like.

[0038]

The electrostatic recording paper for sublimation printing of the present invention uses a hydrophilic resin as its dielectric layer or forms a hydrophilic resin layer on the dielectric layer. By suppressing the diffusion of the dye in the direction of the base paper, it is possible to obtain a high image density and a high transfer rate when printing on a cloth.

Further, by laminating the moisture resistance improving layer on the hydrophilic resin layer, the diffusion of the sublimation dye in the direction of the base paper is suppressed, and a high image density and a high transfer rate can be obtained at the time of printing on the cloth. It is possible to prevent deterioration with time due to humidity during charging and development, and improve imageability. In addition, the residual image after printing on the electrostatic recording paper can be reduced, so that the printing durability of the developer can be improved.

The electrostatic recording paper for sublimation printing of the present invention can be used for printing transfer to a cloth by using an ion printer, whereby the image density on the printing cloth can be increased and the density is clear on the cloth. An image having a great impact is formed, and it is possible to manufacture a textile printing fabric having an excellent design.

[0041]

EXAMPLES Examples of the present invention will be shown below. (Example 1) Commercially available electrostatic recording paper (Sliver S manufactured by Sakurai Co., Ltd.)
544CO) on the dielectric layer as a hydrophilic resin layer, a solution of gelatin [beef bone gelatin manufactured by Nitta Gelatin Co., Ltd .: Collotype-1] dissolved in distilled water at a solid concentration of 10% by weight is used. 12) is used and the coating amount after drying is 1.
It was coated at 8 g / m ² to prepare an electrostatic recording paper for sublimation printing of the present invention.

A wet developer for sublimation printing was prepared by the following method.

(Magenta master toner composition) Dye (Disperse Red 60) 4 parts by weight Resin (2-ethylhexyl methacrylate / methyl methacrylate = 85/15 copolymer resin, weight average molecular weight 170,000, GPC measurement)・ ・ ・ 8 parts by weight ・ Charge control agent (zirconium naphthenate: zirconium content 4% by weight) ・ ・ ・ 0.5 parts by weight ・ Charging aid [2-ethylhexyl methacrylate / dimethylaminoethyl methacrylate = 90/10 Copolymer resin, weight average molecular weight 10,000, GPC measurement) 0.4 part by weight Solvent (Isopar G: ex paraffin hydrocarbon, ex paraffin hydrocarbon) 52 parts by weight The above composition in a mayonnaise bottle Glass beads for dispersion (80 g) into a disperser (manufactured by Red Devil: R
C-500) and dispersed for 16 hours to prepare a master toner.

(Wet developer) 9 parts by weight of the above-prepared master toner was diluted with 150 parts by weight of Isopar G to prepare a wet developer for sublimation printing.

Charging characteristics (charge amount) of the obtained wet developer
Was measured by the following method.

Cell for measuring current value (electrode plate interval 10 mm)
Filled with a wet developer, and the plate (electrode plate area 45 mm x 4
The voltage value of 1000 V was applied to 5 mm), and the current value was monitored for 60 seconds (manufactured by KEITHLEY: Model 237).

The charge amount Q ₀ was calculated as an integrated value of the current value (I (t)). This Q ₀ and the current value (I (6
0)), the charge amount _Qt was calculated by the following equation.

Q _t = Q ₀ −I (60) × 60 On the other hand, the electrode plate having the wet developer adhered thereto was pulled out from the current value measuring cell and dried, and then the toner adhesion amount (M) on the electrode plate was calculated. . The adhesion amount and Q _t from the toner specific charge (Q /
M) was calculated by the following formula.

Q / M = _Qt / M The charging characteristics of the wet type developer prepared above are shown below.

[0050]

[Table 1]

(Development) Using the wet developer prepared as described above, an ion printer having a latent image gradation controllability of 256 gradations was used, and 25 gradation step output control was performed from the maximum output. A latent image of 10 gradations was written on the electrostatic recording paper for sublimation printing.

Then, the magenta toner prepared above was used for roller development to form a gradation pattern of 10 gradations. O of the obtained image on the electrostatic recording paper
D value (OD paper (s): s is a parameter indicating each gradation)
Was measured using a Macbeth reflection densitometer (RD918). The image density at each gradation is the OD paper (s) in Table 2 below.
Shown in In addition, the humidity at the time of development in this example, Examples 2 to 3 described later, and Comparative Example 1 is 40% (26 ° C.) to 4%.
It was 2% (24 ° C). (Thermal transfer) The obtained electrostatic recording paper was combined with polyester fiber cloth (Lite Ace: manufactured by Toray Co., Ltd.), and a thermal transfer machine (manufactured by Hashima Co., model HP-54A) was used.
The fabric was heated at 30 ° C. for 30 seconds to create a gradation pattern printing image on the fabric. The OD value (OD cloth (s): s is a parameter indicating each gradation) of the image on the obtained cloth was measured using a Macbeth reflection densitometer (RD918).
The image density at each gradation is shown in OD cloth (s) in Table 2 below. Similarly, the image density (OD residue (s): s is a parameter indicating each gradation) at each gradation on the residual paper after transfer printing is measured, and the image density at each gradation is O in Table 2 below.
It is shown in D residue (s).

(Calculation of Apparent Transfer Rate) From the image density on the cloth after printing [OD cloth (s)] and the image density on the residual paper after printing [OD residue (s)], the appearance of the dye at each gradation The transfer printing efficiency (STY (s)) of was calculated from the following formula.

[0054] The apparent transfer printing efficiency of each gradation is shown in STY (s) in Table 2 below.

The apparent transfer printing efficiency changes depending on the image density (OD paper (s)) at the time of development. Therefore, when studying, the OD was set as the apparent transfer printing efficiency.
It is necessary to compare STY (s) where the paper (s) has a constant value. Therefore, in Examples and Comparative Examples of the present invention, STY at OD paper (s) = 1.0 for each material
(S) is defined as "apparent transfer rate", and the value is shown in Table 2 together with the image density on the cloth. The rate of increase is OD cloth (s) / OD paper (s). The image density on the cloth after printing [OD (cloth)] and the image density on the residual paper after printing [OD] with respect to the image density on the electrostatic recording paper [OD (paper)]
(Remaining)] are shown in FIG. 1 at the same time.

[0056]

[Table 2]

From Table 2 and FIG. 1, the electrostatic recording paper for sublimation printing of the present invention has a low image density [OD (residual)] at each gradation on the residual paper after transfer printing, and also on the cloth after printing. It can be seen that the image density [OD (cloth)] of is high.

(Example 2) Polyvinyl alcohol (manufactured by Shin-Etsu Chemical Co., Ltd., saponification degree 99.92%: AT) was used as the gelatin in Example 1 in distilled water to obtain a solid content of 10%.
An electrostatic recording paper for sublimation printing according to the present invention was prepared in the same manner as in Example 1 except that the solution dissolved in wt% was used, and the maximum image density on the cloth after printing as in Example 1 and its transfer The rate was measured. The measurement results are shown in Table 3 below.

Example 3 The gelatin used in Example 1 was replaced with polyvinyl alcohol (Nippon Gosei Kagaku Kogyo Co., Ltd.).
Electrostatic recording paper for sublimation printing according to the present invention in the same manner as in Example 1 except that the solution prepared by dissolving and having a saponification degree of 99% or more: NM-11) was dissolved in distilled water at a solid concentration of 10% by weight. Was prepared, and the maximum image density on the cloth after printing and its transfer rate were measured in the same manner as in Example 1. The measurement results are shown in Table 3 below.

Comparative Example 1 Development and printing were carried out in the same manner as in Example 1 except that the electrostatic recording paper on which the hydrophilic resin layer was not laminated was used. The image density and its transfer rate were measured. The measurement results are shown in Table 3 below.

For comparison, Example 1 is also shown.

[0062]

[Table 3]

As can be seen from the table, the electrostatic recording paper for sublimation printing of the present invention has a high maximum image density on the cloth after printing and a high transfer efficiency.

Example 4 Gelatin [Beef bone gelatin manufactured by Nitta Gelatin Co., Ltd .: Collotype-] was used as a hydrophilic resin layer on the dielectric layer of a commercially available electrostatic recording paper (Sliver S544CO manufactured by Sakurai Co., Ltd.). 1] was dissolved in distilled water at a solid content concentration of 10% by weight to obtain a solution using a Miyabar (# 12).
The coating amount after drying at 0 ° C. for 10 minutes is 1.8 g / m ²
It applied so that it might become.

Then, an acrylic resin (BR-10 manufactured by Mitsubishi Rayon Co., Ltd.) was formed on this surface as a moisture resistance improving layer.
1, molecular weight 160,000) toluene: methyl ethyl ketone =
A solution prepared by dissolving a solid content concentration of 10% by weight in a 1: 1 mixed solvent was dried at 100 ° C. for 10 minutes using a Miyabar (# 12) so that the coating amount was 1.6 g / m ^2. To prepare an electrostatic recording paper for sublimation printing of the present invention.

(Evaluation of Charging Characteristics) The charging characteristics of the produced electrostatic recording paper for sublimation printing were evaluated with a paper analyzer. The measurement conditions are shown below, and the measurement results are shown in Table 4 below.

Equipment: Electrostatic Paper Analyzer Model E
PA-8100 Applied voltage: 5 kV Voltage polarity: Negative Application time: 60 seconds Observation time after application: 60 seconds The environmental humidity at the time of measurement was 47% (23 ° C).

In Table 4 below, Vm is the maximum charging voltage value at the time of voltage application, V ₆₀ is the voltage at the end of the voltage application (after 60 seconds), and V ₁₂₀ is the voltage at the time of 60 seconds after the voltage application. .

The development is carried out in the same manner as in Example 1,
Similarly, the OD (paper) was measured. However, the humidity during development is 51
% (23 ° C.). Further, thermal transfer was performed in the same manner as in Example 1, and OD (cloth) and OD (residual) values were measured in the same manner as in Example 1. Also, as in Example 1, the apparent transfer rate was obtained.

The results are also shown in Table 4 below.

(Example 5) Example 4 was repeated except that the bar (# 8) was used instead of the bar (# 12) when the moisture resistance improving layer was formed in the electrostatic recording paper for sublimation printing of Example 4. Similarly, an electrostatic recording paper for sublimation printing was prepared. The coating amount of the moisture resistance improving layer was 1.3 g / m ² . The obtained electrostatic recording paper for sublimation printing was evaluated in the same manner as in Example 4. The results are shown in Table 4 below.

Example 6 Example 4 was repeated except that the bar (# 4) was used in place of the bar (# 12) when the moisture resistance improving layer was formed on the electrostatic recording paper for sublimation printing of Example 4. Similarly, an electrostatic recording paper for sublimation printing was prepared. The coating amount of the moisture resistance improving layer was 0.7 g / m ² . The obtained electrostatic recording paper for sublimation printing was evaluated in the same manner as in Example 4. The results are shown in Table 4 below.

Table 4 below also shows the results of Comparative Example 1 described above.

[0074]

[Table 4]

As can be seen from the table, the electrostatic recording paper for sublimation printing of the present invention has a high maximum image density on the cloth after printing and a high transfer efficiency. Further, it is understood that the charging characteristics can be made equivalent to those of the conventional electrostatic recording paper.

[Brief description of drawings]

FIG. 1 is a diagram showing a relationship between an OD value of an image on an electrostatic recording paper for sublimation printing of the present invention and an image density on a cloth after printing.

Claims (5)

[Claims] 1. An electrostatic recording paper for sublimation printing, wherein a hydrophilic resin layer is provided on a conductive base paper. 2. An electrostatic recording paper for sublimation printing, wherein a hydrophilic resin layer is provided on a conductive base paper, and a moisture resistance improving layer is provided on the hydrophilic resin layer. 3. An electrostatic recording paper for sublimation printing, wherein a dielectric layer is provided on a conductive base paper, and a hydrophilic resin layer is provided on the dielectric layer. 4. An electrostatic dye for sublimation printing characterized in that a dielectric layer and a hydrophilic resin layer are sequentially provided on a conductive base paper, and a moisture resistance improving layer is provided on the hydrophilic resin layer. Recording paper. 5. The hydrophilic resin is gelatin as claimed in claim 1.
The electrostatic recording paper for sublimation printing according to claim 4.