JP3024293B2 - Video photographic paper - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to video photographic paper.
In particular, the present invention relates to a video photographic paper having a receiving layer mainly composed of a polyvinyl aromatic carboxylic acid ester or a copolymer thereof.

[0002]

2. Description of the Related Art Conventionally, an ink ribbon having a dye layer containing a sublimable disperse dye has been applied to a thermal head or the like.
Attempts have been made in video photographic paper to form an image consisting of dyes transferred to the surface of a resin-coated paper by heating in a dot-like manner in response to an image signal. The video printing paper has a two-layer structure of a receiving layer and a sheet-like substrate, and the receiving layer receives (receives) an image of a dye, for example, a sublimable disperse dye, migrating from an ink ribbon, and receives the image. Is a layer for maintaining the image formed by the above. Conventionally, as a material constituting the receiving layer, polyester, polycarbonate,
A polyvinyl chloride copolymer or the like has been used.

[0003]

However, in the conventional video photographic paper in which the receiving layer is made of these resins, the formed image has insufficient dyeing properties, light fastness and weather fastness. In some cases, sharpness was reduced or discolored. This is presumably because the dye transferred 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. SUMMARY OF THE INVENTION An object of the present invention is to eliminate the drawbacks of the prior art and to provide a video photographic paper in which the image formed by the transfer of the dye has excellent light fastness and weather fastness.

[0004]

In order to achieve the above-mentioned object, a video photographic paper of the present invention has a receiving layer to which a dye which has been melted or sublimated by heating is transferred, and is transferred to the receiving layer. In a video printing paper on which an image is formed by a dye, the receiving layer contains a polyvinyl aromatic carboxylic acid ester or a copolymer thereof. Further, the receiving layer is made of another resin compatible with the polyvinyl aromatic carboxylic acid ester or its copolymer.
It is characterized by containing 0% by weight or less. Furthermore, the receiving layer is characterized by containing a compound for improving the dyeing property. Further, the compound for enhancing dyeing properties is an ester compound or a urethane compound.

A video printing paper according to the present invention is, for example, shown in FIG.
As shown in FIG. 1, a receiving layer 3 is formed on a sheet-like substrate 2. This video photographic paper is used in combination with an ink ribbon having a dye layer containing a dye which is transferred by melting or sublimation by heat, for example, and the dye which has been melted or sublimated by heating is transferred to the receiving layer 3 mainly composed of resin. Thus, an image is formed.

In the above-mentioned video printing paper, the receiving layer is formed of polyvinyl aromatic carboxylic acid ester or aromatic carboxylic acid vinyl ester copolymer (aliphatic carboxylic acid ester, acrylic acid, acrylic acid derivative, methacrylic acid, methacrylic acid derivative, styrene, By using styrene derivative, acrylonitrile, acrylonitrile derivative, vinyl alcohol, maleic acid, a copolymer of maleic acid derivative and aromatic carboxylic acid vinyl ester as the main material, it is possible to solve the drawbacks in the prior art. It is a thing.

Here, in order to improve the properties such as dyeing properties, it is preferable that the degree of polymerization of the poly (vinyl aromatic carboxylate) or a copolymer thereof is 400 or more. Further, in the vinyl aromatic carboxylate copolymer, it is preferable that the other monomer component is constituted in a composition ratio of 0 to 0.5 mol per 1 mol of the vinyl aromatic carboxylate. Polyvinyl aromatic carboxylate improves the adhesiveness by being a copolymer, but when the ratio of other monomer components increases, the heat resistance deteriorates and the blocking deteriorates.

The polyvinyl aromatic carboxylic acid ester or its copolymer is produced by the following two methods. 1. (Radical) polymerization or copolymerization with aromatic carboxylic acid vinyl esters (monomers) or other vinyl monomers. 2. (Polymer) reaction between polyvinyl alcohol or its copolymer and aromatic carboxylic acid or its derivative.

Examples of the vinyl aromatic carboxylate include vinyl m-chlorobenzoate, vinyl p-chlorobenzoate, vinyl 2,4-dichlorobenzoate,
Vinyl 3,4,5-tetrachlorobenzoate, vinyl m-nitrobenzoate, vinyl p-nitrobenzoate, vinyl p-cyanobenzoate, vinyl o-toluate, vinyl m-toluate, vinyl p-toluate, Vinyl m-anisate, vinyl p-anisate, vinyl salicylate, vinyl p-acetylbenzoate, vinyl p-dimethylaminobenzoate, vinyl o-acetylsalicylate, vinyl 3,4,5-trimethoxybenzoate, 1-naphthoe Vinyl acid, 2-
Vinyl naphthoate, vinyl p-phenylbenzoate, 2-
Vinyl naphthyl benzoate, vinyl α-stilbene carboxylate, vinyl o-phthalimidobenzoate, vinyl p-phthalimidobenzoate, vinyl anthracene-1-carboxylate, trans-vinyl cinnamate, vinyl p-methoxycinnamate, 2 Many compounds such as vinyl furancarboxylate, vinyl coumalylate, vinyl 2-thiophenecarboxylate, vinyl 2-thionaphthenecarboxylate, vinyl nicotinate and the like are known. (In the present invention, many aromatic carboxylic esters described herein can be used, but the present invention is not limited to this description.) For radical polymerization of vinyl aromatic carboxylate, vinyl benzoate is used. Is mainly studied as a monomer. According to the results, it is reported that the homopolymerizability of vinyl benzoate is extremely poor and that it has no practical significance because a high polymer cannot be obtained. One possible reason for the low activity of the vinyl benzoate radical is that the radical is stabilized by a benzene nucleus as shown in Chemical formula 1.

[0010]

Embedded image

On the other hand, the inventors consider that the chemical structure of the polyvinyl aromatic carboxylate is optimal for the printing conditions obtained from the dyes and video equipment used by the inventors, and After extensive studies on increasing the degree of polymerization, the results showed that 1,1′-azobis (cyclohexane-1-carbonitrile), 4,4
The 4'-azobis (4-cyanovaleric acid) radical polymerization initiator (catalyst) is extremely effective, and the use of this type of catalyst allows the aromatic carboxylic acid vinyl ester to be used alone in a usual polymerization mode such as bulk polymerization or solution polymerization. It has been found possible to synthesize polymers.

Further, since it is difficult to obtain a high molecular weight polymer by homopolymerization of an aromatic carboxylic acid vinyl ester, a (polymer) reaction between polyvinyl alcohol or a copolymer thereof and an aromatic carboxylic acid or a derivative thereof has been used. A method for synthesizing a polyvinyl aromatic carboxylic acid ester has been reported. (For example, H. Staudin
ger, Ber. 60 , 1782 (1972) Noma et al.
Koka, 4 , 34 (1947); Tsuda, Mak
romol, Chem. 72, 174 (1964)
etc),

In the present invention, esters or urethanes are added to the polyvinyl aromatic carboxylic acid ester or a copolymer thereof in the resin of the receiving layer for the purpose of developing a higher-performance receiving layer. By adding the esters or urethanes, various properties such as dyeing properties, light resistance, and dark fading resistance are further improved.

First, among the esters, many compounds generically referred to as "plasticity" can be used for this purpose, and there are also many compounds whose synthesis or suitability has been specifically studied for this purpose. Specifically, aromatic or aliphatic, aliphatic of alicyclic polybasic acid, or ester with alicyclic alcohol, ester with phenols, aromatic or polyhydric alcohol (including phenols) or An aliphatic carboxylic acid ester having a boiling point of 180 ° C. or higher at normal pressure is effective. In the following, compounds suitable for this purpose are listed, but these are merely representative ones, and the compounds applicable to the present invention are not limited to these.

First, as the polyhydric phenol ester,
Catechol diacetate, catechol dipropionate, catechol dibutyrate, catechol dibenzoate, catechol di-o-toluate, catechol di-p-toluate, catechol acetate / benzoate, catechol dicrotonate, resorcinodiacetic acid Ester, resorcin dibutyrate, resorcin acetic acid / benzoate, resorcin dibenzoate, hydroquinone diacetate, hydroquinone benzoate, hydroquinone dicaproate, pyrogallol triacetate, pyrogallol tribenzoate, bisphenol A butyrate, Bisphenol A benzoate, 4,4′-methylenebis- (2,6-di-isopropyl) diacetate, 4,4'-thiobisphenol butyrate and the like.

Examples of the polyhydric alcohol ester include ethylene glycol dibenzoate, diethylene glycol di-p-toluate glycerin tribenzoate, glycerin triacetate pentaerythritol tetrapropionate, pentaerythritol tetrabenzoate, Examples include hydrogenated bisphenol A diacetate, hydrogenated bisphenol A dibenzoate, dipentaerythritol benzoate, and the like.

The phthalic acid esters include dimethyl phthalate, diethyl phthalate, dibutyl phthalate, dioctyl phthalate,
Diphenyl phthalate, dicresyl phthalate, phenylethylene phthalate, dibenzol phthalate, diphenoxyethyl phthalate, dicyclohexyl phthalate, dimethyl isophthalate, diphenyl isophthalate, dibenzyl isophthalate, And diethyl terephthalate.

As the aromatic polybasic acid ester, triethyl trimellitate, tribenzyl trimellitate, trioctyl trimellitate,
Tetraethyl pyromellitic acid ester, tetracyclohexyl pyromellitic acid ester and the like.

Examples of the alicyclic carboxylate include dioctyltetrahydrophthalate, diphenyltetrahydrophthalate, dibenzyltetrahydrophthalate and the like.

Examples of the aliphatic polybasic acid ester include diphenyl succinate, dimethyl succinate, dibenzyl succinate, dibenzyl adipate, dimethyl adipate, diethyl azelate, dibenzyl sebacate, diphenyl Sebacate, diethyl maleate, dibenzyl maleate, diphenyl maleate, dibenzyl fumarate, diphenyl fumarate, tribenzyl citrate,
Acetyl tribenzyl citrate; dimethyl itaconate;

Examples of the phosphate ester include triphenyl phosphate, tribenzyl phosphate, cresyl diphenyl phosphate, trixylyl phosphate, tricyclohexyl phosphate, tetrakis (2,4-di-tert-phosphate). Butylphenyl) -4,4 '
-Biphenyl phosphate and the like. Examples of the carbonate include diphenyl carbonate, di-o-methylphenyl carbonate, di-p-methylphenyl carbonate, dinaphthyl carbonate, di-o-phenylphenyl carbonate, di-p-phenylphenyl carbonate, and dioctyl. Carbonates and the like.

Examples of the monoester include 2,2,4-trimethyl-pentanediol monophthalate, phenylmonophthalate, methylstearate, phenyllaurate, benzylsalicylate, propyl-p-hydroxybenzoate. Acid esters and the like.

In addition, methoxybenzoic acid benzyl ester, phenoxybenzoic acid butyl ester and the like can also be used.

Examples of N-alkylcarbamic acid esters and aryl (substituted) carbamic acid esters (hereinafter abbreviated as urethane) which are effective as additives include 1,6-hexamethylenedibutylurethane and 1,6-hexamethylenedioctyl. Urethane, m-xylenedibutylurethane, p-xylenedioctylurethane, 2,4-toluenedihexylurethane, 2,6-toluenedibenzylurethane, 4,4′-diphenylmethanedibutylurethane, 4,4′-diphenylmethanedioctylurethane,
Ethylenediphenylurethane, 1,4-tetramethylenediphenylurethane, 1,6-hexamethylenedi-p-
Examples thereof include methylphenyl urethane, p-xylenedi-p-chlorophenyl, o-xylenedibutylbutylurethane, and m-xylenedicyclohexylurethane.

The amount of the ester or urethane compound is in the range of 1 to 70% by weight, more preferably 5 to 50%, based on the polyvinyl aromatic carboxylic acid ester or a copolymer thereof. These are added at the time of solution or heat melting, and after sufficient mixing, used as a resin.

Although all of the above are low molecular compounds (monomers), oligomers thereof can also be used for carrying out the present invention. For example, oligopolyesters of dibasic acids and glycols, ring-closing oligoesters of cyclic esters, low molecular weight polymers of vinyl esters, oligourethanes (glycol components excess) obtained from glycols and diisocyanates, and more specifically, polytetraadipate Polyhexamethylene succinate, poly-m-xylene glycol sebacate, polycaprolactone, poly (vinyl benzoate), oligourethane obtained by reacting 2 mol of hexamethylene diisocyanate with 3 mol of tetramethylene glycol, 2 mol of m-xylene diisocyanate and octa Oligourethane or the like obtained by reacting 3 moles of methylene glycol and having a degree of polymerization of 5 or less is suitable.

Further, a mixture of polyvinyl aromatic carboxylic acid ester or a copolymer thereof to which an ester or urethane compound is added and another resin compatible with the mixture is blended to form a receiving layer having better characteristics. The material is obtained. Specific examples of other resins are shown below. The following resins can be used alone or as a mixture of several types, but the resins used in the present invention are not limited to these. (A) Those having an ester bond. Polyester resin, polyacrylate resin, polycarbonate resin, polyvinyl acetate resin, styrene acrylate resin, vinyl toluene acrylate resin. (B) Those having a urethane bond. Polyurethane resin and the like. (C) Those having an amide bond. Polyamide resin. (D) Those having a urea bond. Urea resin and the like. (C) 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. (all manufactured by Toyobo Co., Ltd.), UE3600, XA6098, XA702
6 (all made by Unitika), TP220, TP235
(All manufactured by Nippon Gosei Co., Ltd.). Examples include aromatic dibasic acids and glycols, aliphatic dibasic acids and glycols, aromatic dibasic acids, and mixed polyesters of aliphatic dibasic acids and glycols. Urethane resins include polyethers having a hydroxyl group at the molecular end or ether-type polyurethanes made from polyester and isocyanate, and ester-type polyurethanes.Resins having an amide bond include, for example, nylon and other diamines having a branched group. There are polyamides derived from dimer acid and the like. As the compound having a urea bond, a reaction product of urea and an aldehyde can be used in addition to a compound obtained by reacting a diamine acid with a diisocyanate.
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 a mixture of a polyvinyl aromatic carboxylic acid ester or a copolymer thereof and an ester or a urethane compound is used in combination with another resin, 100 parts by weight of the polyvinyl ester and the additive are added to the other resin. 1 to 100 parts by weight can be used.

In order to improve the whiteness of the receiving layer to enhance the sharpness of the transferred image, to give the image surface writability, and to prevent the transferred image from being retransferred, the fluorescent whitening in the receiving layer 3 is performed. Agents and white pigments can be added. Examples of the optical brightener include Ubitex OB manufactured by Ciba-Geigy.
Many compounds that are commercially available as optical brighteners can be used. Examples of white pigments include titanium oxide, zinc oxide, kaolin, clay, calcium carbonate, and finely divided silica, and these can be used alone or in combination of two or more. Further, in order to improve the light fastness of the transferred image, one or two or more additives such as an ultraviolet absorber, a light stabilizer, or an antioxidant are added in the receiving layer.
More than one species can be added as needed. The amounts of these fluorescent brighteners, white pigments, ultraviolet absorbers, light stabilizers and the like added are 0.0 to 100 parts by weight of the cellulose ester resin.
Although 5 to 10 parts by weight is suitable, an amount outside the range may be added depending on the purpose, and the above addition amount is merely an example, and therefore, is limited by this addition amount. Not something.

The video printing paper of the present invention may contain a release agent in the receiving layer in order to improve the releasability 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 phosphate-based surfactants, silicone oil, and high-melting silicone wax, with silicone oil being preferred. For example, the silicone oil may be oily or reactive (curable) type, and is used according to the purpose. Examples of the reaction (curing) type silicone include alcohol-modified silicone oil and isocyanate. Further, as the reaction (curing) type silicone oil, 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 An oil (amino / polyether-modified silicone oil) and a carboxy-modified silicone oil (carboxy-polyether-modified silicone oil) which are cured by reaction are also preferable. The thickness of the release agent layer is preferably 0.01 to 5 μm, but is not particularly limited to this thickness.

In order to suppress the generation of static electricity during the processing step of video photographic paper or during running in a printer, an antistatic agent may be contained in the cellulose ester resin system, in the receiving layer or on the surface of the receiving layer.

As the antistatic agent, a surfactant such as a cationic surfactant (for example, quaternary ammonium salt,
Polyamine derivatives, etc.), anionic surfactants (eg, alkyl benzene sulfonate, alkyl sulfate sodium salt), zwitterionic surfactants and nonionic surfactants. These antistatic agents may be applied to the surface of the receptor layer by coating or the like, or may be added to the polyvinyl aromatic carboxylic acid ester or its copolymer.

On the other hand, the dye used for the ink ribbon is optional, but specific examples include the following dyes. (1) Methine dye (A) (Macrolex Yel)
low 6G Bayer) (2) Methine dye (B) (Foron Brilli
(3) anthraquinone dye (C) (Macrolex)
(Red Violet® Bayer) (4) Azo dye (D) (Sumikaron Red
S-BDF (Sumitomo Chemical Co., Ltd.) (5) Indoaniline dye (E)

For example, a method for synthesizing an indoaniline derivative is as follows. First, 3 g of 2- (n-butyroylamino) -4,6-dichloro-5-methylphenol was dissolved in 200 g of ethanol, and sodium carbonate 8 g was added thereto.
g was dissolved in 100 g of water, and the mixture was stirred well. There, 4-amino-N (β-hydroxyethyl) -N-
A solution prepared by dissolving 5 g of ethyl-m toluidine sulfate in 100 g of water was added and stirred for 30 minutes.
5 g is added little by little, and when the addition is completed, the mixture is stirred for 10 minutes, 300 g of water is added, and the mixture is filtered to obtain dye crystals.

[0036]

When a polyvinyl aromatic carboxylate or a copolymer thereof is used as the main component of the receiving layer, the dyeing property, weather resistance and light resistance are improved as compared with the case where another polyester resin or the like is used. Be improved. Further, an ester or a urethane compound is added to the polyvinyl aromatic carboxylic acid ester or the copolymer thereof, or a mixture of the polyvinyl aromatic carboxylic acid ester or the copolymer thereof and the ester or the urethane compound is compatible with the mixture. When the resin is mixed, the light resistance is further improved.

[0037]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below based on experimental results.

Polyvinyl benzoate aromatic carboxylic acid S
Synthesis of ter and its copolymerPolyvinyl benzoate aromatic carboxylate and its copolymer can be produced by polymerization and copolymerization of vinyl aromatic carboxylate. An example of synthesis of polyvinyl benzoate by bulk polymerization, solution polymerization of p-tert-butyl vinyl benzoate and vinyl propionate, and reaction of polyvinyl alcohol with benzoic acid chloride will be described.

(1) Bulk polymerization of vinyl benzoate 15 g of vinyl benzoate (Shin-Etsu Vinyl Acetate) was purified by distillation under reduced pressure (73-75 ° C./3 mmHg) and
50 ml of 0.04 g of 1,1′-azobis (cyclohexane-1-carbonitrile) [manufactured by Wako Pure Chemical Industries, Ltd.]
And the air in the ampule is replaced with nitrogen gas by a freezing replacement method, and then sealed. Then, the ampoule is set in a hot water tank and heated at 70 ± 1 ° C. for 15 hours. At this time, the contents in the ampoule become viscous about 15 minutes after the start of heating,
After an hour, it becomes a slightly yellowish glassy solid. After heating the ampoule for a predetermined time, it is left to cool to room temperature, further cooled with liquid nitrogen, and opened. After dissolving the polymer synthesized in the ampoule in toluene and taking out the solution, a toluene solution of the polymer is gradually dropped into vigorously stirred methanol to obtain a white powdery polymer. The polymer yield at this time was 98%.

With respect to the polymer thus obtained,
The compatibility and the softening point were examined, the infrared absorption spectrum was analyzed, and the molecular weight was examined by gel filtration chromatography. FIG. 2 shows the infrared absorption spectrum of the monomer.
FIG. 3 shows the infrared absorption spectrum of the polymer, and FIG. 4 shows the elution pattern of the gel filtration chromatography.

First, when the compatibility of the polymer was examined, the polymer was dissolved in toluene, cyclohexanone, dioxane, methylcellosolve, ethyl acetate and tetrahydrofuran, and was insoluble in methanol, isopropanol, n-hexane and cyclohexane. It showed poor solubility. After dissolving this polymer in tetrahydrofuran, it was made into a film (transparent), and the melting point of this polymer film was measured with a microscope equipped with a heating plate. did.

From the results of the infrared absorption spectrum analysis, as can be seen by comparing FIG. 2 and FIG. 3, the infrared absorption spectrum of the polymer film indicates the absorption of the vinyl group observed in the infrared absorption spectrum of the monomer. 1500 to 1575 cm ^-1 , 1616 to 16 which are considered to indicate
98cm ^-1, 847cm ^-1, except that peak at 948cm ^-1 is disappeared, in good agreement with the infrared absorption spectrum of the monomer. From this, it was confirmed that the synthesized polymer was polybenzoic acid vinyl ester. Further, the obtained polymer in tetrahydrofuran solution was subjected to gel filtration chromatography (GPC), and the obtained peak fraction was examined for molecular weight, degree of polymerization, and molecular weight distribution. Table 1 shows the results.

[0043]

[Table 1]

(2) Solution polymerization of p-tert-butyl vinyl benzoate and vinyl propionate First, a 500 ml four-necked flask equipped with a stirrer, a backflow cooler, a thermometer, and a nitrogen gas inlet tube was placed in a water bath. Set to. And p-te purified by distillation under reduced pressure
25 g of vinyl rt-butyl benzoate (manufactured by Tokyo Chemical Industry Co., Ltd.), 2.5 g of vinyl ester of propionate (manufactured by Tokyo Chemical Industry Co., Ltd.), 110 g of propyl acetate (special grade of reagent manufactured by Wako Pure Chemical Industries, Ltd.) Was charged into a four-necked flask, and stirred while introducing nitrogen gas (flow rate 100 ml / min) into the flask.
1 'azobis (cyclohexane-1-carbonitrile)
(Wako Pure Chemical Industries, Ltd., reagent) 0.07g is added. Then, heating was performed so that the temperature of the content liquid became 80 ° C. in about 30 minutes, and heating was continued for 10 hours in that state. At this time, 5 hours after the temperature of the content liquid reached 80 ° C.,
1 'azobis (cyclohexane-1-carbonitrile)
Add 0.07 g. After heating for 10 hours, the content liquid becomes a viscous, slightly yellowish transparent liquid. The solution thus obtained is used as it is for the receiving layer of the video photographic paper.

When methanol was added to the solution thus obtained, a white polymer precipitated. Therefore, only the polymer was separated and the polymerization yield was measured to be 82%.
The number average molecular weight of the main peak measured in the above was 89,00
0 was indicated.

(3) Synthesis of polyvinyl benzoate by reaction of polyvinyl alcohol and benzoic acid chloride Stirrer, thermometer, dropping funnel, and counter-flow cooler (equipped with calcium chloride tube on top) set in a mantle heater In a 500 ml four-necked flask equipped with a gas introduction tube, polyvinyl alcohol (trade name: Gohsenol AH-17, manufactured by Nippon Synthetic Chemical Industry Co., Ltd., viscosity: 25-30)
(Hepler viscometer, 4% aqueous solution, 20 ° C) Saponification degree 9
7.0 to 98.5, volatile matter 5% or less, ash content 0.7% or less, pH (4% aqueous solution) 4 to 7, particle size 16 mesh or less 8.8g (stored in a desiccator containing silica gel for one week) ) And 300 ml of pyridine (special grade reagent, manufactured by Wako Pure Chemical Industries, Ltd.) and slowly stirring at room temperature for 24 hours while introducing nitrogen gas into the flask. Thereafter, 34 g of benzoic acid chloride (manufactured by Wako Pure Chemical Industries, Ltd., reagent grade) is dropped from the dropping funnel. Simultaneously with the dropping, the turbidity of the content liquid increased, and the internal temperature rose. At the end of the dropping of the chloride, the liquid temperature rose by about 11 ° C. After the liquid temperature stabilizes, gradually heat,
After about 1 hour, the temperature is raised to 60 ° C. Heating is continued for 10 hours in this state. During this time, the content liquid becomes translucent yellow-brown. After the heating was completed, the contents were allowed to cool to room temperature, and vigorously stirred.
Add slowly into 0% methanol water. A white precipitate forms upon addition. The white granular precipitate was separated by filtration, washed with 80% methanol water and warm methanol three times, and after confirming that chloride ions were not observed in the washing liquid, drying under reduced pressure (10 m
mHg, 50 ° C, 48 hours).

The dried product is a white granular material, which is dissolved in toluene, methyl ethyl ketone, tetrahydrofuran and ethyl acetate. Tetrahydrofuran solution (concentration 0.250 g / 1
00ml), the intrinsic viscosity was 2.01, and the infrared absorption spectrum of the film (prepared from tetrahydrofuran solution) was consistent with that of the radical polymer of vinyl benzoate.

Further, the content of vinyl benzoate measured according to JIS K6730 (the calculation formula for measuring the content of vinyl acetate is JIS K6730, but since the measurement principle is the same, the coefficient is changed to vinyl benzoate. Calculated) was 96.3%. This value includes the raw material polyvinyl alcohol (JISK of Gohsenol AH-17).
(Saponification degree 98.0% measured by a method according to 6726)
Because of the above measurement results, the polymer synthesized in this example was found to contain 94.3% of vinyl benzoate, 2.0% of vinyl acetate, and 3.7 of vinyl alcohol. % Terpolymer based on vinyl benzoate.

An ester compound to be added to the polymer,
All of the urethane compounds used were commercial products (for compounds not described in catalogs or the like, the chemical structures were shown and the synthesis was requested). (Commercial purchase company, Tokyo Chemical Industry Co., Ltd., Wako Pure Chemical Industries, Dojin Chemical Laboratory, Aldrich Chemi
cal Co)

Preparation of Receiving Layer Sheet The receiving layer sheet was prepared by coating a receiving layer composition having the following composition on a 150 μm synthetic paper (trade name: FPG-150, manufactured by Oji Yuka Co., Ltd.) so as to have a dry film thickness of 10 μm. And 50 ° C,
It was created by curing for 48 hours.
The composition of the receiving layer composition is shown below. Tables 2 and 3 show the types of the polyvinyl aromatic carboxylic acid ester or the copolymer thereof used in each sheet. Receiving layer composition Polyvinyl aromatic carboxylate or copolymer thereof 20.0 parts by weight Isocyanate 1.0 part by weight (Takenate D-110N, manufactured by Takeda Pharmaceutical Co., Ltd.) Modified silicone oil 0.6 part by weight (Toray Dow) Corning Co., Ltd., trade name SF8427) Fluorescent brightener 0.04 parts by weight (Ciba Geigy Co., Ltd., trade name Ubitex OB) Methyl ethyl ketone 40.0 parts by weight

Ink ribbon Y used : yellow (print material ribbon VPM-30ST manufactured by Sony Corporation) M: magenta (print material ribbon VPM-30ST manufactured by Sony Corporation) C: cyan (print material ribbon VPM-30ST manufactured by Sony Corporation) The method of producing the used ink ribbon is as follows. Ink layer composition Dye 3.70 parts by weight Ethyl hydroxyethyl cellulose 7.42 parts by weight (manufactured by EHEC-LOW Hercules) Toluene 44.44 parts by weight Methyl ethyl ketone 44.44 parts by weight

The mixture having the above composition was stirred to prepare an ink. Then, a dry film thickness of about 1 μm was formed on a 6 μm polyethylene terephthalate (PET) film obtained by back-treating the ink layer composition using a coil bar.
Was applied to prepare a sublimation transfer sheet, which was used as an ink sheet.

Thermal Transfer Recording In the thermal transfer recording, an ink sheet and a receptor layer sheet are printed on a color video printer (CVP-G50, manufactured by Sony Corporation).
0) was used to perform 12-step steer step printing.

Light fastness test The receiving layer sheet subjected to gradation printing was irradiated with 60,000 KJ / m ² by a xenon arc fade meter (manufactured by Gas Testing Machine). Measure the density before and after irradiation with a Macbeth reflection thermometer (TR-9).
24 type), the highest 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. Residual rate of dye (%) = concentration after xenon irradiation / concentration before xenon irradiation × 100

The dark-fading test The tone-printed receiving layer sheet was held in a thermo-hygrostat (Tavai) at 65 ° C., 85% RH for 10 days, and was measured using a Macbeth reflection densitometer (TR-924). The maximum density part and the density change before and after the test near the density of 1.0 were measured, and the residual ratio of the dye was calculated according to the following equation. Residual rate of dye (%) = concentration after test / concentration before test × 100

Dyeing Density Measurement Using a Macbeth reflection densitometer (TR-924), the highest density part of the receiving layer sheet on which gradation printing was performed was measured. The measurement results are shown in Tables 2 and 3 together with the type of polymer used.

[0057]

[Table 2]

[0058]

[Table 3] * 4 1: Synthesized according to benzoic acid bulk polymerization 2: p-te
rt-Butyl vinyl benzoate Synthesized according to solution polymerization of vinyl propionate * 5 Molar ratio * 6 Polyvinyl alcohol (trade name, manufactured by Nippon Synthetic Chemical Company) Gohsenol AH-17 Gohsenol M-300 GH-17 * 7 Polyester (Toyo) Spinon Byron 206) * 8 Polyester (above) 20 parts + Dicyclohexyl phthalate 4 parts

From the test results shown in the table, when the polyaromatic carboxylic acid ester or its copolymer is used, the degree of dyeing is improved 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 light fastness and fading test was high, and the durability such as light fastness and fading fastness was improved.

Addition of Ester Compounds and Urethane Compounds Receptive layers were formed by adding various ester compounds and urethane compounds to poly (vinyl benzoate) or vinyl benzoate vinyl acetate copolymer. The types and amounts of the ester compound and the urethane compound are as shown in Tables 4 and 5.

[0061]

[Table 4]

[0062]

[Table 5]

The photographic papers are similarly E
The P image performance (dye density, light fastness, dark color fastness) was examined. Tables 6 to 8 show the measurement results.

[0064]

[Table 6]

[0065]

[Table 7]

[0066]

[Table 8]

It can be seen that the use of a polyaromatic carboxylic acid ester or a copolymer thereof to which an ester compound or a urethane compound is added further improves the durability such as light resistance and fading resistance.

It should be noted that the present invention is not limited to the above-described embodiment, but can adopt various other configurations without departing from the gist of the present invention.

[0069]

According to the present invention, since a polyvinyl aromatic carboxylic acid ester or a copolymer thereof is used as the main component of the receiving layer of the video photographic paper, it is compared with the case where a polyester resin or the like is used. Light resistance can be improved.
Further, a mixture obtained by adding an ester or a urethane compound to a polyvinyl aromatic carboxylic acid ester or a copolymer thereof, and further a mixture of the mixture with another resin compatible with the mixture is used as a main component of the receiving layer. So
Thereby, light resistance can be further improved.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a video photographic paper.

FIG. 2 is a characteristic diagram showing an infrared absorption spectrum of vinyl benzoate (monomer).

FIG. 3 is a characteristic diagram showing an infrared absorption spectrum of a vinyl benzoate polymer.

FIG. 4 is an elution pattern of a polymer by gel filtration chromatography.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Video printing paper 2 Sheet-like base material 3 Reception layer

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B41M 5/38-5/40

Claims (4)

(57) [Claims] 1. A video photographic paper having a receiving layer to which a dye which has been melted or sublimated by heating is transferred, wherein an image is formed by the dye transferred to the receiving layer, wherein the receiving layer is a polyvinyl aromatic carboxylic acid. A video photographic paper comprising an acid ester or a copolymer thereof. 2. The video printing paper according to claim 1, wherein the receiving layer contains 50% by weight or less of another resin compatible with the polyvinyl aromatic carboxylic acid ester or a copolymer thereof. 3. The video photographic paper according to claim 1, wherein the receiving layer contains a compound for enhancing the dyeing property. 4. The video printing paper according to claim 3, wherein the compound for improving the dyeing property is an ester compound or a urethane compound.