JPH0532068A - Video photographic paper - Google Patents

Abstract

PURPOSE:To provide the above video photographic caper in which light fastness of an image formed by transfer of dye to its acceptor layer is excellent. CONSTITUTION:The subject video photographic paper is obtained as follows: in the video photographic paper 1 wherein dye is transferred to an acceptor layer 3 principally consisting of resin of photographic paper by heating the dye or ink containing the dye supported on a substratum to be fused or sublimated and an image is formed resin of the acceptor layer 3 is principally pullulan ester.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video printing paper,
In particular, it relates to a video printing paper having a receiving layer mainly composed of pullulan ester.

[0002]

2. Description of the Related Art Conventionally, an ink ribbon having a dye layer containing a sublimable disperse dye is used by a thermal head or the like.
Attempts have been made on video printing paper to form an image composed of dye transferred to the surface of resin-coated paper by heating it in spots according to an image signal.

This video printing paper has a two-layer structure in which a receiving layer is formed on a sheet-shaped substrate. The receiving layer is a layer for receiving (receiving) an image of a dye that migrates from the ink ribbon, for example, a sublimable disperse dye, and maintaining the image formed by the receiving. Conventionally, polyester, polycarbonate, polyvinyl chloride copolymer, and the like have been used as the material forming the receiving layer.

[0004]

However, the conventional video printing paper having the receptive layer made of these resins does not have sufficient light resistance and weather resistance of the formed image, and the sharpness of the image once formed decreases. It could be discolored or discolored.
This is considered to be easily affected by light, humidity, oxygen in the air, etc., because the dye that migrates by the thermal head or the like exists near the surface of the receiving layer.

It is an object of the present invention to overcome the drawbacks of the prior art and to provide a video printing paper in which the image formed by dye transfer has excellent light and weather resistance.

[0006]

As shown in FIG. 1, for example, a video printing paper according to the present invention melts or sublimates a dye or an ink containing the dye supported on a substrate by heating so that the dye is mainly used as the printing paper. In a video printing paper that transfers to a receiving layer 3 made of resin to form an image, the receiving layer 3
The resin is mainly pullulan ester.

In the video printing paper of the present invention, the resin of the receiving layer 3 contains 50% by weight or less of another resin compatible with pullulan ester. Further, the video printing paper of the present invention contains a compound for improving the dyeing property by the resin of the receiving layer 3 being compatible with each other.

[0008]

According to the present invention, by making the composition of the receiving layer 3 a pullulan ester-based resin, the dyeing property and light resistance can be improved as compared with the case where a conventionally used polyester resin or the like is used. Further, the dyeability and the light resistance can be improved by blending a compound that improves the dyeability with the pullulan ester resin. Further, the light resistance can be further improved by blending the pullulan ester resin with another resin.

[0009]

EXAMPLES Examples of the video printing paper of the present invention will be described below. In this example, the ink ribbon is used in combination with an ink ribbon having a dye layer containing a dye that melts or sublimates and transfers by heat, and the dye that migrates from the ink ribbon is received on the surface of the sheet-shaped substrate. A video printing paper having a receptive layer, wherein the receptive layer is mainly composed of pullulan ester (pullulan acetate ester, pullulan benzoate ester, pullulan-P or O-methyl benzoate ester, etc.) That is, the drawbacks of the conventional technology can be solved. The video printing paper 1 of this example has a structure having a receiving layer 3 on a sheet-shaped substrate 2 as shown in FIG. 1, for example.

The pullulan ester contained in the receiving layer is produced by reacting pullulan with an aliphatic carboxylic acid or an aromatic carboxylic acid or a derivative thereof. The aliphatic carboxylic acid used in the synthesis here may be a saturated carboxylic acid or an unsaturated carboxylic acid, preferably having 1 to 18 carbon atoms, more preferably about 1 to 5 carbon atoms. . If the carbon number exceeds the above range, introduction becomes difficult.

In the esterification of these pullulan with an aliphatic carboxylic acid, an aromatic carboxylic acid, or a derivative thereof, it is sufficient that the produced compound is soluble in an organic solvent, and therefore, it is contained in one molecule of pullulan. It is desirable that at least 3 out of 9 hydroxyl groups involved are involved in the reaction. Also, since pullulan ester is a natural product,
Its molecular weight is very large and its number average molecular weight is tens of thousands or more.

A. Method for producing pullulan benzoic acid ester by reaction of pullulan and benzoic acid chloride Pretreatment of pullulan 8 g of commercially available pullulan (manufactured by Tokyo Chemical Industry Co., Ltd., reagent) is dissolved in 80 ml of warm water (ion exchange), and this solution is vigorously stirred. It is added dropwise to 200 ml of methanol (first-grade reagent) to give a white granular insoluble matter, which is filtered off, washed with methanol several times, and dried under reduced pressure (10 mmHg, 1 week) at room temperature to obtain a sample.

A reaction stirrer for pullulan and benzoic acid chloride , a backflow cooler (a calcium chloride tube was attached to the tip) thermometer, a dropping funnel, and a four-necked flask equipped with a nitrogen gas introduction tube were set in a mantle heater, To this, pre-treated 8 g of pullulan, 200 ml of dried dioxane (manufactured by Wako Pure Chemical Industries, Ltd., special grade reagent dried and distilled with molecular sieve) 200 ml, dried pyridine (manufactured by Wako Pure Chemical Industries Ltd, special grade reagent) 20 ml were charged. , Slowly stir while feeding nitrogen gas (flow rate 100 ml / min).

Then, 24 g of benzoic acid chloride (reagent, manufactured by Tokyo Kasei Kogyo Co., Ltd.) is dropped from the dropping funnel (because it generates heat, it is added at a rate such that the internal temperature does not exceed 40 ° C.). After the internal temperature becomes constant, the internal temperature is heated to 90 ° C. in about 1 hour, and the reaction is performed at 90 to 95 ° C. for 15 hours. Meanwhile, the content liquid becomes viscous when the internal temperature is around 90 ° C., and eventually becomes a yellowish brown uniform solution.

After the heating is completed, the contents are allowed to cool to room temperature, and 5
Add dropwise while stirring vigorously in 0% methanol water. The powdery precipitate formed was filtered off, and further washed with warm methanol several times until chlorine ions were not observed in the washing liquid, and dried under reduced pressure (10 mmHg, 50 ° C., 48 hours).
To do.

The reaction product was dissolved in tetrahydrofuran, dioxane, dimethylformamide and cyclohexanone at room temperature, and a color test showing the presence of an ester group [F. Feigl, V. Anger] was conducted. , Microchemical 15, 12 (1934)] clearly shows the presence of an ester group.

Tetrahydrofuran solution (concentration 0.250
g / 100 ml) has an intrinsic viscosity of 1.92, and the infrared absorption spectrum of the film (prepared from a tetrahydrofuran solution) shows an ester bond near 1750 cm ^−1.
The absorption of the monosubstituted aromatic compound strongly appears around 00 cm ^-1 . From the measurement of the content of ester bond by the method according to ASTM D871-63, it is estimated that 7.2 out of 3 hydroxyl groups of pullulan (per 1 basic unit) are pullulan benzoate ester converted into benzoate ester bond. It

B. Method for producing pullulan acetate by reaction of pullulan and acetic anhydride In the same apparatus as used in the reaction of pullulan and benzoic acid chloride, 8 g of pretreated pullulan and dry pyridine [Wako Pure About Kogyo Co., Ltd. , Special reagent] 200 ml was charged, and nitrogen gas was fed in while stirring (flow rate 200 m
l / min). 17.6 g of acetic anhydride is added dropwise from the dropping funnel. The internal temperature rises by about 6 ° C by the dropping. After the internal temperature has become constant, heating is performed and the temperature is raised to about 100 ° C. one hour later.
React for 10 hours at an internal temperature of 100 ° C. During this time, the contents become a viscous pale yellow transparent solution.

After completion of heating, the mixture is allowed to cool to room temperature, and then dropped into 50% methanol water with vigorous stirring. A cotton-like insoluble matter is formed at the same time as the dropping. Insoluble matter is 50%
It was washed several times with methanol water and then with methanol until the smell of pyridine disappeared, and dried under reduced pressure (10 mmHg, 50 ° C.,
48 hours).

The reaction product is dissolved in methyl ethyl ketone, tetrahydrofuran, ethyl acetate and methyl cellosolve. Tetrahydrofuran solution (concentration, 0.250 g /
The intrinsic viscosity of 100 ml) is 1.82, and the infrared absorption spectrum of the film (prepared from a tetrahydrofuran solution) shows strong absorption of ester bond at around 1750 cm ^-1 . The color reaction (1,2) also clearly shows the presence of ester bonds. The degree of substitution of hydroxyl groups is calculated to be 2.6 by measuring the content of acetyl groups according to ASTM D871-63.

From the above measurement results and raw materials, the product of this reaction is presumed to be pullulan acetate.

As the esters, ethers and hydrocarbon compounds which are compatible with the pullulan esters and act as additives for increasing the dyeing property of the dye and improving the light resistance and heat resistance, various compounds are available. Yes, the compounds exemplified below are
That is just one example. It is considered that these compounds are compatibilized with pullulan esters to promote the diffusibility of the dye, and have the function of allowing the dye to penetrate into the inside of the receiving layer.

For example, phthalic acid esters such as dimethyl phthalate, diethyl phthalate, dioctyl phthalate dicyclohexyl phthalate, diphenyl phthalate, dioctyl adipate, dioctyl separate,
Aliphatic dibasic acid esters such as dicyclohexyl azelate, phosphoric acid esters such as triphenyl phosphate, tricyclohexyl phosphate, triethyl phosphate, and isophthalic acid esters such as dimethyl phthalate, diethyl isophthalate and dicyclohexyl isophthalate And higher fatty acid esters such as butyl stearate and cyclohexyl laurate, silicic acid esters such as tetraethyl silicate and tetraphenyl silicate, and boric acid esters such as tributyl borate and triphenyl borate.

As the esters, diphenyl ether,
Examples thereof include dicyclohexyl ether and P-ethoxybenzoic acid methyl ester. As a hydrocarbon compound,
Camphor, low-molecular-weight polystyrene, and phenols such as P-phenylphenol and O-phenylphenol,
Examples thereof include sulfonic acid amides such as N-ethyltoluenesulfonic acid amide.

Mixtures of pullulan esters and other resins can also form the receiving layer. For example, the resins shown below can be used alone or as a mixture of several kinds, but the resins are not limited to the resins shown below, and the following are only specific examples.

(A) Those having an ester bond Polyester resin, polyacrylic acid ester resin, polycarbonate resin, polyvinyl acetate resin, styrene acrylate resin, vinyl toluene acrylate resin. (B) Polyurethane resin having a urethane bond. (C) Those having an amide bond. Polyamide resin. (D) A compound having a urea bond. Urea resin etc. (E) Other. Polycaprolactone resin, polystyrene resin, polyvinyl chloride and its copolymer, polyacrylonitrile and its copolymer.

As the saturated polyester, for example, Byron 200, Byron 290, Byron 600, etc. (above,
Toyobo Co., Ltd.), UE3600, XA6098, XA70
26 (above, Unitika company), TP220, TP235
(Above, manufactured by Nippon Gosei Co., Ltd.) and the like are used. Examples include aromatic dibasic acids and glycols, aliphatic dibasic acids and glycols, aromatic and basic acids, and mixed polyesters of aliphatic dibasic acids and glycols.

As the urethane resin, there are ether type polyurethane and ester type polyurethane made from polyether or polyester having a hydroxyl group at the molecular end and isocyanate. Examples of the resin having an amide bond include nylon and the like, as well as a polyamide derived from a diamine having a branched group, dimer acid and the like.

As the compound having a urea bond, not only a compound obtained by the reaction of a diamine acid and a diisocyanate but also a reaction product of urea and an aldehyde can be used. Further, a wide range of materials such as polycaprolactone having an ester bond, polystyrene, vinyl chloride and its copolymer, and polyacrylonitrile copolymer can be used.

When the pullulan ester resin is used in combination with another resin, it depends on the type of pullulan ester resin,
It is possible to use 1 to 100 parts by weight of other resins with respect to 100 parts by weight of the pullulan ester resin.

On the other hand, for the purpose of improving the whiteness of the receiving layer to enhance the sharpness of the transferred image, imparting writability to the image surface, and preventing retransfer of the transferred image, the fluorescent increase in the receiving layer 3 Whitening agents and white pigments can be added.

As the optical brightener, many compounds commercially available as optical brighteners, such as Ubitex OB manufactured by Ciba-Geigi Co., can be used. As white pigments, titanium oxide, zinc oxide, kaolin,
There are clay, calcium carbonate, fine powder silica and the like, and these can be used alone or in combination of two or more kinds.

Further, in order to improve the light fastness of the transferred image, one or more additives such as an ultraviolet absorber, a light stabilizer, an antioxidant and the like may be added to the receptor layer, if necessary. You can These optical brighteners, white pigments,
The addition amount of the ultraviolet absorber, the light stabilizer, etc. is suitably 0.05 to 10 parts by weight with respect to 100 parts by weight of the pullulan ester resin, but depending on the purpose, an amount outside the range may be added, The above-mentioned addition amount is merely an example, and is not limited to this addition amount.

The video printing paper of the present invention may contain a releasing agent in the receiving layer in order to improve the releasing property from the ink ribbon sheet. Examples of the releasing agent include solid waxes such as polyethylene wax, amide wax, and Teflon powder, fluorine-based and phosphoric acid ester-based surfactants, silicone oil, and high-melting-point silicone wax, with silicone oil being preferred.

For example, the silicone oil may be oily or reactive (curing) type, and may be used depending on the purpose. Examples of the reaction (curing) type silicone include alcohol-modified silicone oil and isocyanate. Further, the reaction (curing) type silicone oil is obtained by reacting and curing an epoxy-modified silicone oil (epoxy / polyether-modified silicone oil) and a carboxy-modified silicone oil (carboxy / polyether-modified silicone oil), or an amino-modified silicone. Those obtained by reacting and curing oil (amino / polyether-modified silicone oil) and carboxy-modified silicone oil (carboxy / polyether-modified silicone oil) are also preferable. The thickness of the release agent layer is 0.01 to
The thickness is preferably 5 μm, but is not particularly limited to this thickness.

An antistatic agent may be added to the pullulan ester resin system, the receiving layer or the surface of the receiving layer in order to suppress the generation of static electricity during the process of processing the video printing paper or during running in the printer.

As the antistatic agent, a surface active agent such as a cationic surface active agent (for example, a quaternary ammonium salt,
Examples thereof include polyamine derivatives), anionic surfactants (eg, alkylbenzene sulfonate, sodium alkyl sulfate ester salt), and zwitterionic surfactants or nonionic surfactants. These antistatic agents may be formed on the surface of the receiving layer by coating or added to the pullulan ester resin.

-Specific contents of the embodiment- Hereinafter, the specific contents of the embodiment of the video printing paper of the present invention will be described with reference to Chemical Formulas 1 to 3, Tables 1 to 3 and FIG.

(1) Dyes used in this example In this example, the following dyes were used as the ink layer forming composition. Methine dye (A) (Macrolex Yellow 6
G, manufactured by Bayer) methine dye (B) (Foron Brilliant Blue SR-PI, manufactured by Sandts) anthraquinone dye (C) (Macrolex Red Violet R, manufactured by Bayer) Azo dye (D ) (Sumikaron Red S-BDF,
Sumitomo Chemical Co., Ltd. Indoaniline dye (E) Yellow (Printing material ribbon VPM-30ST, Sony Corporation) Magenta (Printing material ribbon VPM-30ST, Sony Corporation) Cyan (Printing material ribbon VPM-30ST, Sony (manufactured by Sony Corporation) Yellow (printed material ribbon UPC-3010, manufactured by Sony Corporation) Magenta (printed material ribbon UPC-3010, manufactured by Sony Corporation) Cyan (printing material ribbon UPC-3010, manufactured by Sony Corporation) The above India The structural formula of the aniline dye (E) is
As shown in.

[0040]

[Chemical 1]

The method for synthesizing this dye is as follows. First, to synthesize an indoaniline derivative, 3 g of 2- (n-butyroylamino) -4,6-dichloro-5-methylphenol was dissolved in 200 g of ethanol, and 8 g of sodium carbonate was dissolved in 100 g of water. Add and stir well. There, 4-amino-N (β
-Hydroxyethyl) -N-ethyl-m toluidine sulfate (5 g) dissolved in 100 g of water was added and stirred for 30 minutes,
15 g of sodium hypochlorite solution was added little by little, and when the addition was completed, the mixture was stirred for 10 minutes, 300 g of water was added, and filtration was performed to obtain dye crystals. The reaction formula is shown below.

[0042]

[Chemical 2]

Next, 2 g of the crystals of the dye thus obtained were dissolved in 50 g of pyridine, 0.6 g of butyryl chloride was added little by little, and the mixture was refluxed for 1 hour for esterification. The reaction formula is shown below.

[0044]

[Chemical 3]

Then, the obtained compound was purified by subjecting it to column chromatography (filler: Wako Pure Chemical Industries Ltd., trade name Wakogel C-200) using chloroform as a developing solvent, and used as Dye 1.

(2) Preparation of Ink Sheet Next, an ink layer composition containing the above dyes was prepared according to the following composition.

[0047] Ink layer composition   Dye (to dye) 3.70 parts by weight   Ethyl hydroxyethyl cellulose 7.42 parts by weight   (Made by EHEC-LOW Hercules)   Toluene 44.44 parts by weight   Methyl ethyl ketone 44.44 parts by weight

An ink was prepared by stirring the mixture having the above composition. Then, this ink layer composition was applied onto a 6 μm polyethylene terephthalate (PET) film back-treated with a coil bar so that the dry film thickness was about 1 μm to prepare a sublimation type transfer sheet, which was used as an ink sheet. Using each of the ink sheets prepared as described above, thermal transfer recording was performed on a receiving layer sheet which is a transfer target.

(3) Preparation of Receptor Layer Sheet The receptor layer sheet was prepared by coating the receptor layer composition on a synthetic paper of 150 μm (trade name: FPG-150 manufactured by Oji Yuka Co., Ltd.) to have a dry film thickness of 10
It was formed by coating so as to have a thickness of μm and curing at 50 ° C. for 48 hours. The composition of the receiving layer composition is shown below. Receptor layer composition resin 20.0 parts by weight (see Table 1) Compound for improving dyeability 0 to 4 parts by weight (see Table 1) Isocyanate 1.0 parts by weight (Takenate D-, manufactured by Takeda Pharmaceutical Co., Ltd.) 110N) Modified silicone oil 0.6 parts by weight (Toray Dow Corning, trade name SF8427) Optical brightener 0.04 parts by weight (Ciba Geigy, trade name Ubitex OB) Methyl ethyl ketone 40.0 parts by weight

[0050]

[Table 1]

(4) Thermal transfer recording In thermal transfer recording, an ink sheet and a receiving layer sheet are formed by a color video printer (manufactured by Sony Corporation, trade name CVP-G50).
0) was used to carry out 12-step gradation printing.

(5) Light resistance test The gradation-printed receptor layer sheet was irradiated with a xenon arc fade meter (manufactured by Suga Test Instruments Co., Ltd.) at 60,000 KJ / m ² . Macbeth reflection densitometer (TR-9
24 type), the maximum density part and the gradation part near the density of 1.0 were measured, and the residual ratio of the dye was calculated according to the following formula (4).

[0053]

[Equation 1]

(6) Dark Fading Test Gradation-printed receptor layer sheets were kept at 65 ° C. and 85% RH for 10 days in a thermo-hygrostat (Tabay), and a Macbeth reflection densitometer (TR-924) was used. The density change before and after the test at the highest density part and around 1.0 was measured, and the residual ratio of the dye was calculated according to the following equation (5).

[0055]

[Equation 2]

(7) Measurement of Dyeing Density Using a Macbeth reflection densitometer (TR-924), the highest density part of the gradation-printed receiving layer sheet was measured. The results of the dyeing density, light resistance test and dark fading test of the printed image using the polymer of the present invention as the receiving layer are collectively shown in Tables 2 and 3.

[0057]

[Table 2]

[0058]

[Table 3]

From the test results of Tables 2 and 3, the use of the polymer of the present invention improves the dyeing degree, the light resistance, and the light resistance, as compared with the conventionally used polyester resins (Comparative Examples 1 and 2). It can be seen that the residual ratio of the dye after the fading test is high and the durability such as light resistance and fading resistance is improved.

The present invention is not limited to the above-described embodiments, and it goes without saying that various other configurations can be adopted without departing from the gist of the present invention.

[0061]

According to the present invention, by using a pullulan ester resin as the composition of the receiving layer, the dyeing property and the light resistance can be improved as compared with the case of using the conventionally used polyester resin or the like. The dyeability and light resistance can be improved by incorporating a compound that enhances the dyeability into the pullulan ester resin. On the other hand, by blending the pullulan ester-based resin with another resin, the dyeing property and the light resistance can be further improved in some cases.

[Brief description of drawings]

FIG. 1 is a sectional view of a video printing paper.

[Explanation of symbols]

1 Video printing paper 2 Sheet-shaped substrate 3 Receptive layer

─────────────────────────────────────────────────── ───

[Procedure amendment]

[Submission date] October 7, 1992

[Procedure Amendment 1]

[Document name to be amended] Statement

[Name of item to be amended] Detailed explanation of the invention

[Correction method] Change

[Correction content]

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video printing paper,
In particular, it relates to a video printing paper having a receiving layer mainly composed of pullulan ester.

[0002]

2. Description of the Related Art Conventionally, an ink ribbon having a dye layer containing a sublimable disperse dye is used by a thermal head or the like.
Attempts have been made on video printing paper to form an image composed of dye transferred to the surface of resin-coated paper by heating it in spots according to an image signal.

This video printing paper has a two-layer structure in which a receiving layer is formed on a sheet-shaped substrate. The receiving layer is a layer for receiving (receiving) an image of a dye that migrates from the ink ribbon, for example, a sublimable disperse dye, and maintaining the image formed by the receiving. Conventionally, polyester, polycarbonate, polyvinyl chloride copolymer, and the like have been used as the material forming the receiving layer.

[0004]

However, the conventional video printing paper having the receptive layer made of these resins does not have sufficient light resistance and weather resistance of the formed image, and the sharpness of the image once formed decreases. It could be discolored or discolored.
It is considered that this is because the dye that migrates by the thermal head or the like exists near the surface of the receiving layer and is easily affected by light, humidity, oxygen in the air, and the like.

It is an object of the present invention to overcome the drawbacks of the prior art and to provide a video printing paper in which the image formed by dye transfer has excellent light and weather resistance.

[0006]

In the video printing paper according to the present invention, a dye or an ink containing the dye supported on a substrate is melted or sublimated by heating to transfer the dye to a receiving layer mainly composed of a resin of the printing paper. In a video printing paper which forms an image by means of a resin, the resin of the receiving layer is mainly pullulan ester.

In the video printing paper of the present invention, the resin for the receiving layer contains 50% by weight or less of another resin compatible with pullulan ester. Further, the video printing paper of the present invention contains a compound for enhancing the dyeing property by the resin of the above-mentioned receiving layer being compatible with each other.

The video printing paper of the present invention is used by combining an ink ribbon with an ink ribbon having a dye layer containing a dye which is melted or sublimated by heat to migrate, and the ink ribbon is formed on the surface of a sheet-like substrate. A video printing paper having a receptive layer for receiving a more migrating dye, the receptive layer comprising pullulan ester (pullulan acetate, pullulan benzoate, pullulan-P or O).
By using methyl benzoate etc.) as a main material, the drawbacks of the conventional technique could be solved. For example, the above video printing paper has a structure having a receiving layer 3 on a sheet-shaped substrate 2 as shown in FIG.

The pullulan ester contained in the receiving layer 3 is produced by reacting pullulan with an aliphatic carboxylic acid, an aromatic carboxylic acid or a derivative thereof. The aliphatic carboxylic acid used in the synthesis here may be a saturated carboxylic acid or an unsaturated carboxylic acid, preferably having 1 to 18 carbon atoms, more preferably about 1 to 5 carbon atoms. . If the carbon number exceeds the above range, introduction becomes difficult.

In the esterification of these pullulan with an aliphatic carboxylic acid or an aromatic carboxylic acid or a derivative thereof, it is sufficient that the produced compound is soluble in an organic solvent, so that it is contained in one molecule of pullulan. It is desirable that at least 3 out of 9 hydroxyl groups involved are involved in the reaction. Also, since pullulan ester is a natural product,
Its molecular weight is very large and its number average molecular weight is tens of thousands or more.

As the esters, ethers and hydrocarbon compounds which are compatible with the pullulan esters and act as additives for increasing the dyeing property of the dye and improving the light resistance and heat resistance, various compounds are available. Yes, the compounds exemplified below are
That is just one example. It is considered that these compounds are compatibilized with pullulan esters to promote the diffusibility of the dye, and have the function of allowing the dye to penetrate into the inside of the receiving layer.

For example, phthalic acid esters such as dimethyl phthalate, diethyl phthalate, dioctyl phthalate dicyclohexyl phthalate, diphenyl phthalate, dioctyl adipate, dioctyl separate,
Aliphatic dibasic acid esters such as dicyclohexyl azelate, phosphoric acid esters such as triphenyl phosphate, tricyclohexyl phosphate, triethyl phosphate, and isophthalic acid esters such as dimethyl phthalate, diethyl isophthalate and dicyclohexyl isophthalate And higher fatty acid esters such as butyl stearate and cyclohexyl laurate, silicic acid esters such as tetraethyl silicate and tetraphenyl silicate, and boric acid esters such as tributyl borate and triphenyl borate.

As the esters, diphenyl ether,
Examples thereof include dicyclohexyl ether and P-ethoxybenzoic acid methyl ester. As a hydrocarbon compound,
Camphor, low-molecular-weight polystyrene, and phenols such as P-phenylphenol and O-phenylphenol,
Examples thereof include sulfonic acid amides such as N-ethyltoluenesulfonic acid amide.

Mixtures of pullulan esters and other resins can also form the receiving layer. For example, the resins shown below can be used alone or as a mixture of several kinds, but the resins are not limited to the resins shown below, and the following are only specific examples.

(A) Those having an ester bond Polyester resin, polyacrylic acid ester resin, polycarbonate resin, polyvinyl acetate resin, styrene acrylate resin, vinyl toluene acrylate resin. (B) Polyurethane resin having a urethane bond. (C) Those having an amide bond. Polyamide resin. (D) A compound having a urea bond. Urea resin etc. (E) Other. Polycaprolactone resin, polystyrene resin, polyvinyl chloride and its copolymer, polyacrylonitrile and its copolymer.

For example, as the saturated polyester, Byron 200, Byron 290, Byron 600, etc. (above,
Toyobo Co., Ltd.), UE3600, XA6098, XA70
26 (above, Unitika company), TP220, TP235
(Above, manufactured by Nippon Gosei Co., Ltd.) and the like are used. Examples include aromatic dibasic acids and glycols, aliphatic dibasic acids and glycols, aromatic and basic acids, and mixed polyesters of aliphatic dibasic acids and glycols.

As the urethane resin, there are ether type polyurethane and ester type polyurethane made from polyether or polyester having a hydroxyl group at the molecular end and isocyanate. Examples of the resin having an amide bond include nylon and the like, as well as a polyamide derived from a diamine having a branched group, dimer acid and the like.

As the compound having a urea bond, in addition to the compound obtained by the reaction of diamine acid and diisocyanates, a reaction product of urea and aldehydes can be used. Further, a wide range of materials such as polycaprolactone having an ester bond, polystyrene, vinyl chloride and its copolymer, and polyacrylonitrile copolymer can be used.

When the pullulan ester resin is used in combination with another resin, it depends on the type of pullulan ester resin.
It is possible to use 1 to 100 parts by weight of other resins with respect to 100 parts by weight of the pullulan ester resin.

Fluorescent whitening in the receiving layer 3 for the purpose of improving the whiteness of the receiving layer to enhance the sharpness of the transferred image, imparting writability to the image surface, and preventing retransfer of the transferred image. Agents and white pigments can be added.

As the optical brightener, many compounds commercially available as optical brighteners such as Ubitex OB manufactured by Ciba-Geigy can be used. As white pigments, titanium oxide, zinc oxide, kaolin,
There are clay, calcium carbonate, fine powder silica and the like, and these can be used alone or in combination of two or more kinds.

Further, in order to improve the light resistance of the transferred image, one or more additives such as an ultraviolet absorber, a light stabilizer, or an antioxidant may be added to the receptor layer, if necessary. You can These optical brighteners, white pigments,
The addition amount of the ultraviolet absorber, the light stabilizer, etc. is suitably 0.05 to 10 parts by weight with respect to 100 parts by weight of the pullulan ester resin, but depending on the purpose, an amount outside the range may be added, The above-mentioned addition amount is merely an example, and is not limited to this addition amount.

The video printing paper of the present invention may contain a releasing agent in the receiving layer in order to improve the releasing property from the ink ribbon sheet. Examples of the release agent include solid waxes such as polyethylene wax, amide wax, and Teflon powder, fluorine-based and phosphoric acid ester-based surfactants, silicone oil, and high-melting-point silicone wax, with silicone oil being preferred.

For example, the silicone oil may be oily or reaction (curing) type, and may be used depending on the purpose. Examples of the reaction (curing) type silicone include alcohol-modified silicone oil and isocyanate. Further, the reaction (curing) type silicone oil is obtained by reacting and curing an epoxy-modified silicone oil (epoxy / polyether-modified silicone oil) and a carboxy-modified silicone oil (carboxy / polyether-modified silicone oil), or an amino-modified silicone. Those obtained by reacting and curing oil (amino / polyether-modified silicone oil) and carboxy-modified silicone oil (carboxy / polyether-modified silicone oil) are also preferable. The thickness of the release agent layer is 0.01 to
The thickness is preferably 5 μm, but is not particularly limited to this thickness.

An antistatic agent may be contained in the pullulan ester resin system, the receiving layer or the surface of the receiving layer in order to suppress the generation of static electricity during the process of processing the video printing paper or during running in the printer.

As the antistatic agent, a surface active agent such as a cationic surface active agent (for example, a quaternary ammonium salt,
Examples thereof include polyamine derivatives), anionic surfactants (eg, alkylbenzene sulfonate, sodium alkyl sulfate ester salt), and zwitterionic surfactants or nonionic surfactants. These antistatic agents may be formed on the surface of the receiving layer by coating or added to the pullulan ester resin.

On the other hand, the dye used in the ink ribbon is arbitrary, but if it is specifically exemplified, the following dyes can be mentioned, for example. Methine dye (A) (Macrolex Yellow 6
G, manufactured by Bayer) methine dye (B) (Foron Brilliant Blue SR-PI, manufactured by Sandts) anthraquinone dye (C) (Macrolex Red Violet R, manufactured by Bayer) Azo dye (D ) (Sumikaron Red S-BDF,
Sumitomo Chemical Co., Ltd.) Indoaniline dye (E) For example, the method for synthesizing an indoline derivative is as follows. First, 2- (n-butyroylamino) -4,6
-Dichloro-5 methylphenol 3 g ethanol 20
Dissolve it in 0 g, and add 8 g of sodium carbonate to 100 g of water.
Add the one dissolved in and stir well. A solution prepared by dissolving 5 g of 4-amino-N (β-hydroxyethyl) -N-ethyl-m-toluidine sulfate in 100 g of water was put therein 30
After stirring for 15 minutes, 15 g of sodium hypochlorite solution was added little by little, and when the addition was completed, stirring was continued for 10 minutes, and 300 g of water was added.
And filtered to obtain dye crystals.

[0028]

According to the present invention, by making the composition of the receiving layer 3 a pullulan ester-based resin, the dyeing property and light resistance can be improved as compared with the case where a conventionally used polyester resin or the like is used. Further, the dyeability and the light resistance can be improved by blending a compound that improves the dyeability with the pullulan ester resin. Further, the light resistance can be further improved by blending the pullulan ester resin with another resin.

[0029]

EXAMPLES Preferred examples to which the present invention is applied will be described below based on experimental results.

Synthesis of Pullulan Ester First, a typical synthetic method of pullulan ester is shown below.

A. Process for producing pullulan benzoate by reaction of pullulan with benzoic acid chloride

(1) Pre-treatment of pullulan 8 g of commercially available pullulan (manufactured by Tokyo Kasei Kogyo Co., Ltd., reagent) was dissolved in 80 ml of warm water (ion exchange), and this solution was dripped into 200 ml of vigorously stirred methanol (first-grade reagent). Then, it is made white granular insoluble matter, filtered off, washed with methanol several times, and dried under reduced pressure (10 mmHg, 1 week) at room temperature to obtain a sample.

(2) Reaction of pullulan with benzoic acid chloride A four-necked flask equipped with a stirrer, a backflow cooler (calcium chloride tube attached to the tip) thermometer, a dropping funnel, and a nitrogen gas introduction tube was used as a mantle heater. 8 g of pullulan which was set and pretreated, dried dioxane (manufactured by Wako Pure Chemical Industries, Ltd., special grade reagent dried by molecular sieve and distilled) 200 ml, dried pyridine (manufactured by Wako Pure Chemical Industries Ltd, special grade reagent) Charge 20 ml and stir gently while feeding nitrogen gas (flow rate 100 ml / min).

Then, 24 g of benzoic acid chloride (reagent, manufactured by Tokyo Kasei Kogyo Co., Ltd.) is added dropwise from the dropping funnel (because it generates heat, it is added at a rate such that the internal temperature does not exceed 40 ° C). After the internal temperature becomes constant, the internal temperature is heated to 90 ° C. in about 1 hour, and the reaction is performed at 90 to 95 ° C. for 15 hours. Meanwhile, the content liquid becomes viscous when the internal temperature is around 90 ° C., and eventually becomes a yellowish brown uniform solution.

After heating, the contents were left to cool to room temperature, and 5
Add dropwise while stirring vigorously in 0% methanol water. The powdery precipitate formed was filtered off, and further washed with warm methanol several times until chlorine ions were not observed in the washing liquid, and dried under reduced pressure (10 mmHg, 50 ° C., 48 hours).
To do.

The reaction product was dissolved in tetrahydrofuran, dioxane, dimethylformamide and cyclohexanone at room temperature, and a color test showing the presence of an ester group [F. Feigl, V. Anger] was conducted. , Microchemical 15, 12 (1934)] clearly shows the presence of an ester group.

Tetrahydrofuran solution (concentration 0.250
g / 100 ml) has an intrinsic viscosity of 1.92, and the infrared absorption spectrum of the film (prepared from a tetrahydrofuran solution) shows an ester bond near 1750 cm ^−1.
The absorption of the monosubstituted aromatic compound strongly appears around 00 cm ^-1 . From the measurement of the content of ester bond by the method according to ASTM D871-63, it is estimated that 7.2 out of 3 hydroxyl groups of pullulan (per 1 basic unit) are pullulan benzoate ester converted into benzoate ester bond. It

B. Method for producing pullulan acetate by reaction of pullulan and acetic anhydride In the same apparatus as used in the reaction of pullulan and benzoic acid chloride, 8 g of pretreated pullulan and dry pyridine [Wako Pure About Kogyo Co., Ltd. , Special reagent] 200 ml was charged, and nitrogen gas was fed in while stirring (flow rate 200 m
l / min). 17.6 g of acetic anhydride is added dropwise from the dropping funnel. The internal temperature rises by about 6 ° C by the dropping. After the internal temperature has become constant, heating is performed and the temperature is raised to about 100 ° C. one hour later.
React for 10 hours at an internal temperature of 100 ° C. During this time, the contents become a viscous pale yellow transparent solution.

After completion of heating, the mixture is allowed to cool to room temperature and then added dropwise into vigorously stirred 50% methanol water. A cotton-like insoluble matter is formed at the same time as the dropping. Insoluble matter is 50%
It was washed several times with methanol water and then with methanol until the smell of pyridine disappeared, and dried under reduced pressure (10 mmHg, 50 ° C.,
48 hours).

The reaction product is dissolved in methyl ethyl ketone, tetrahydrofuran, ethyl acetate and methyl cellosolve. Tetrahydrofuran solution (concentration, 0.250 g /
The intrinsic viscosity of 100 ml) is 1.82, and the infrared absorption spectrum of the film (prepared from a tetrahydrofuran solution) shows strong absorption of ester bond at around 1750 cm ^-1 . The color reaction (1,2) also clearly shows the presence of ester bonds. The degree of substitution of hydroxyl groups is calculated to be 2.6 by measuring the content of acetyl groups according to ASTM D871-63.

From the above measurement results and raw materials, the product of this reaction is presumed to be pullulan acetate.

Preparation of Receptor Layer Sheet The receptor layer sheet was prepared by mixing the 150 μm synthetic paper (manufactured by Oji Yuka Co., Ltd., trade name FPG-150) with the receptor layer composition to dryness of 10
It was formed by coating so as to have a thickness of μm and curing at 50 ° C. for 48 hours. The composition of the receiving layer composition is shown below. Table 1 shows the resins used in each sheet and the types and amounts of the compounds added to enhance the dyeing property. Receptor layer composition resin 20.0 parts by weight Compound for enhancing dyeability 0 to 4 parts by weight Isocyanate 1.0 parts by weight (Takenate D-110N, manufactured by Takeda Pharmaceutical Co., Ltd.) Modified silicone oil 0.6 parts by weight (Toray Dow Corning, trade name SF8427) Optical brightener 0.04 parts by weight (Ciba Geigy, trade name Ubitex OB) Methyl ethyl ketone 40.0 parts by weight

[0043]

[Table 1]

Preparation of Ink Sheet Y: Yellow (Ribbon of printing material VPM-30ST,
Sony) M: Magenta (Printing material ribbon VPM-30ST,
Sony Corp.) C: Cyan (printing material ribbon VPM-30ST, Sony Corp.) An ink layer composition containing the above dye was prepared according to the following composition. Ink layer composition Dye 3.70 parts by weight Ethyl hydroxyethyl cellulose 7.42 parts by weight (EHEC-LOW Hercules) Toluene 44.44 parts by weight Methyl ethyl ketone 44.44 parts by weight

Then, an ink was prepared by stirring the mixture having the above composition. Then, this ink layer composition was applied onto a 6 μm polyethylene terephthalate (PET) film back-treated with a coil bar so that the dry film thickness was about 1 μm to prepare a sublimation type transfer sheet, which was used as an ink sheet.

Thermal transfer recording In thermal transfer recording, an ink sheet and a receiving layer sheet are printed on a color video printer (manufactured by Sony Corporation, trade name CVP-G50).
0) was used to carry out 12-step gradation printing.

[0047] 60,000KJ / m ² was irradiated with the light resistance test floor signed image the receiving layer sheet xenon arc fade meter (manufactured by Suga Test Instruments). Macbeth reflection densitometer (TR-9
24 type), the maximum density part and the gradation part near the density of 1.0 were measured, and the residual ratio of the dye was calculated according to the following formula (4).

[0048]

[Equation 1]

Dark Fading Test Gradation-printed receiving layer sheet was kept in a thermo-hygrostat (Tabay) at 65 ° C. and 85% RH for 10 days, and a Macbeth reflection densitometer (TR-924) was used. The density change before and after the test at the highest density part and around 1.0 was measured, and the residual ratio of the dye was calculated according to the following formula (5).

[0050]

[Equation 2]

Dyeing Density Measurement Using a Macbeth reflection densitometer (TR-924), the highest density portion of the gradation-printed receiving layer sheet was measured. The results of the dyeing density, light resistance test and dark fading test of the printed image using the polymer of the present invention as the receiving layer are collectively shown in Tables 2 and 3.

[0052]

[Table 2]

[0053]

[Table 3]

From the test results shown in Tables 2 and 3, the use of the polymer of the present invention improves the dyeing degree, the light resistance, and the light resistance, as compared with the conventionally used polyester resins (Comparative Examples 1 and 2). It can be seen that the residual ratio of the dye after the fading test is high and the durability such as light resistance and fading resistance is improved.

The present invention is not limited to the above-described embodiments, and it goes without saying that various other configurations can be adopted without departing from the gist of the present invention.

[0056]

According to the present invention, by using a pullulan ester resin as the composition of the receiving layer, the dyeing property and the light resistance can be improved as compared with the case of using the conventionally used polyester resin or the like. The dyeability and light resistance can be improved by incorporating a compound that enhances the dyeability into the pullulan ester resin. On the other hand, by blending the pullulan ester-based resin with another resin, the dyeing property and the light resistance can be further improved in some cases.

Claims (3)

[Claims] 1. A video printing paper for forming an image by melting or sublimating a dye or an ink containing the dye supported on a substrate by heating to transfer the dye to a receiving layer mainly composed of a resin of the printing paper to form an image. The video printing paper is characterized in that the resin of is mainly pullulan ester. 2. The video printing paper according to claim 1, wherein the resin of the receiving layer contains 50% by weight or less of another resin compatible with pullulan ester. 3. The video printing paper according to claim 1, wherein the resin of the receiving layer contains a compound that is compatible with each other to enhance the dyeing property.