JPH0539447A - Ink for ink jet recording and method for recording thereof - Google Patents

Abstract

PURPOSE:To obtain an ink having high concentration of recorded picture image and letter, excellent color and color tone of full color image by separately packing volatile disperse dyes of three hues into microcapsules. CONSTITUTION:The interior material of microcapsules is obtained by dispersing volatile disperse dyes into water, a polar organic solvent and at least one of polyester resins, and the dyes have yellow, magenta and cyanic hues and the dye of each hue is separately packed into the microcapsules to give the objective ink.

Description

Detailed Description of the Invention

The present invention relates to an ink jet recording ink comprising microcapsules containing a sublimable disperse dye and a recording method therefor. In particular, the present invention relates to an inkjet recording ink having a high density of images and characters recorded on a recording medium and excellent in color and gradation of a full-color image, and a recording method thereof.

[0002]

2. Description of the Related Art An ink jet recording system is a system for recording fine images such as images and characters by ejecting minute droplets of an ink in which a colored dye is dissolved by various operating principles and adhering them to a recording medium such as paper. However, there are features such as high speed, low noise, easy multicoloring, great flexibility in recording patterns, and no need for development and fixing. Various figures and color images including Kanji. As a recording device such as the above, it is rapidly spreading for various uses. But,
The full-color image formed by the multi-color inkjet recording system is still insufficient in color and gradation when compared with multi-color printing by a photoengraving system or a sublimation type thermal transfer system.

This is because in the ink jet recording system, there is a limit to the apparatus even if the dot density is increased, and it is 300 to 40.
This is because 0 dpi is common. For this reason, various proposals have been made from the recording medium side for the purpose of providing high resolution, high chromaticity, and high gradation.

For example, JP-A-55-5830 discloses an ink jet recording paper having an ink-absorptive coating layer on the surface of a support, and JP-A-55-51583 discloses a pigment in a coating layer as a pigment. Example using colloidal silica powder, JP-A-55
No. 11829 shows an example of a coated paper using a two-layer structure having different ink absorption rates, and in JP-A No. 57-107878, a coating layer containing synthetic silica and colloidal silica is provided on the surface of a support. Examples, JP-A-57-107879 and U
In SP 4,440,827, two or more coating layers containing synthetic silica and colloidal silica are provided on the surface of a support. In JP-A-58-65692, no-size base paper is coated with a pigment and an aqueous polymer. An example of a coated paper obtained by coating a dispersion, agglomeration, and a dry treatment with a water-soluble adhesive, and JP-A-58-72495 discloses a silica pigment having an average particle diameter of 0.05 μm or less and a water-soluble agent. Examples of coated paper coated with a polymer binder, JP-A-58-110287 and USP 4,46
In No. 0,637, one or more coating layers were provided on the surface of the support, and one peak of the pore distribution curve of the uppermost layer was 0.2.
.mu.m to 10 .mu.m, and the peak of the pore distribution curve of all ink receiving layers is at least 0.2 .mu.m to 10 .mu.m and 0.
Two examples having a size of 05 μm or less are disclosed.

In these reference recording media, efforts have been made to obtain high image quality by controlling the dot diameter, chromaticity, ink absorbability, etc. by devising the material surface for coating. As for the gradation, there is a large factor derived from the printing density of the recording apparatus, and satisfactory gradation has not been obtained yet.

On the other hand, regarding the ink for ink jet recording, there is JP-A-1-170672. This publication relates to a recording liquid in which a dye is microencapsulated, and an oil-based ink using an oil-soluble dye as the dye is microencapsulated to obtain a recording liquid, that is, an ink for inkjet recording, which has been conventionally used. The purpose is to improve the light resistance and water resistance, which were the drawbacks of water-soluble dyes.

As described above, in the conventional ink for ink jet recording and its recording method, it is attempted to solve the characteristics of the print density and the chromaticity and gradation of the full color image which can be improved. To do.

[0007]

DISCLOSURE OF THE INVENTION As a result of intensive studies, the inventors of the present invention provide an ink jet recording ink excellent in print density and color and gradation of a full color image, and a recording method thereof. Is.

That is, the ink jet recording ink provided by the present invention is an ink jet recording ink containing microcapsules in a medium composed of water or a water-soluble organic solvent, and the inclusion of the microcapsules is
A recording composition in which a sublimable disperse dye is dissolved or dispersed in at least one of water, a water-soluble organic solvent, and a polyester resin, wherein the sublimable disperse dye is composed of yellow, magenta, and cyan hues, The sublimable disperse dye of each hue is separately encapsulated in microcapsules.

Further, in the ink jet recording method provided by the present invention, the content of the microcapsules is water,
A recording composition in which a sublimable disperse dye is dissolved or dispersed in at least one of a water-soluble organic solvent and a polyester resin, wherein the sublimable disperse dye is yellow, magenta,
It consists of each hue of cyan, the microcapsule is one in which the sublimable disperse dye of each hue is separately encapsulated, and each of the hues of each microcapsule contained in a medium composed of water or a water-soluble organic solvent. Inkjet recording ink is used to perform inkjet recording on a recording medium, and then pressure treatment is performed to destroy the microcapsules, or heat treatment is additionally performed.

Further, in the ink jet recording ink and the recording method thereof of the present invention, the recording medium comprises at least one ink receiving layer coated on the surface of a support,
The ink receiving layer component is mainly composed of an inorganic or organic pigment and a water-soluble polyester resin.

In the present invention, the yellow sublimable disperse dye is one selected from the group consisting of styryl dyes and pyridone azo dyes.

In the present invention, the magenta sublimable disperse dyes are styryl dyes, 1-amino-4-hydroxyanthraquinone dyes, 5-nitrothiazole azo dyes, 3-alkylthio 1,2,4-thiadiazole dyes. , 2-alkylthio-1,3,4-thiadiazole-based azo dyes.

In the present invention, the cyan sublimable disperse dye is one selected from the group consisting of naphthoquinone dyes, anthraquinone dyes, heterocyclic azo dyes and indoaniline dyes.

In the present invention, as the ink for ink jet recording, the ink comprising microcapsules containing a sublimable disperse dye and having an average particle diameter of several microns is used to print using the recording medium of the present invention. By applying pressure treatment to destroy the microcapsules, or heat treatment in addition to this to release the inclusions in the microcapsules onto the recording medium, the color density and gradation of the full-color image can be increased. It has been found that an image having excellent properties can be obtained.

With respect to the reason why an image having high density and excellent color and gradation of a full-color image can be obtained by the present invention,
Description will be made in comparison with a conventional inkjet recording method.

In the conventional recording method, for example, when red is produced by yellow and magenta, several tens are recorded on the recording medium.
A yellow ink drop of micron is printed, and a magenta ink drop of several tens of microns is also printed on the yellow ink drop. Therefore, the absorptivity and the dot diameter of the yellow ink and the magenta ink differ. That is, the magenta ink surrounds the yellow ink on the recording medium and is absorbed deeper and larger than the yellow ink. Further, the respective inks do not sufficiently mix with each other in the overlapping portion.

In contrast to this, with the ink jet recording ink of the present invention, yellow and magenta inks are printed as ink drops of several tens of microns, and the dispersion medium (water or water-soluble) of the microcapsules in each ink is printed. Since the organic solvent) is absorbed and then pressure-treated, the yellow sublimable disperse dye and the magenta sublimable disperse dye, which are microcapsule inclusions, are first mixed or absorbed into the recording medium while being mixed. The feature is that there is no difference in the absorbency and the dot diameter due to each sublimable disperse dye. Therefore, in the present invention, since the mixed sublimable disperse dye is uniformly absorbed in the vicinity of the surface layer of the recording medium, it is considered that high density and color and gradation of a full-color image can be obtained. Gradation is further enhanced by heat treatment after pressurization.

In addition, in the present invention, since the recording medium coated with the ink receiving layer comprising the inorganic or organic pigment and the water-soluble polyester resin is used, the absorbed sublimable disperse dye is fixed to the polyester resin. You also get the advantage of being done.

When the microcapsule inclusions are not released only by the pressure treatment, for example, when the microcapsule inclusions are a composition consisting of a sublimable disperse dye and a polyester resin, the inclusions are heated by the pressure treatment to remove the inclusions. It is preferable to adopt a method of releasing. A method of simultaneously performing pressure-heat treatment such as passing through a nip between a heating roll and a metal roll, or a method of heating while laminating with a heat laminator after applying pressure may be employed.

As the sublimable disperse dye of the present invention, as described above, a sublimable disperse dye composed of yellow, magenta and cyan, which is excellent in sublimability, coloring power, sharpness and light resistance, is used. These are dissolved or dispersed in water or a water-soluble organic solvent, or a polyester resin, and provided as microcapsule inclusions.

In the ink jet recording ink of the present invention, the mixing ratio (% by weight) of the microcapsules dispersed in a medium composed of water or a water-soluble organic solvent is 60% by weight or less based on the total weight of the ink. , Preferably 50% by weight or less. In this case, depending on the viscosity and physical properties of the ink, the mixing ratio may be appropriately changed to a value of about 50 cps or less. Here, if the mixing ratio of the microcapsules exceeds 60% by weight, it may cause clogging of the nozzle holes of the recording apparatus, which is not preferable.

The sublimable disperse dye encapsulated in the microcapsules may be appropriately mixed with water or a water-soluble organic solvent for dissolving or dispersing the dye or a polyester resin in a mixing ratio with respect to the total weight of the inclusions. Is 0.5 to 30% by weight, preferably 1 to 15% by weight. Here, when the mixing ratio of the sublimable disperse dye exceeds 30% by weight, the sublimable disperse dye is difficult to dissolve or the dispersion is not good, which is not desirable.

The method of microencapsulation may be a known method, for example, a complex coacervation method, an interfacial polymerization method, or an in-situ method.
u) A polymerization method, an orifice method, a spray drying method and the like can be mentioned.

The microcapsule dispersion as an ink for ink jet recording is appropriately ink jet recorded depending on the combination of the microcapsule inclusion with water or a water-soluble organic solvent which is a dispersion medium of the sublimable disperse dye, or a polyester resin. The device can be used.

The sublimable disperse dyes used in the present invention are illustrated below, but the invention is not limited thereto.

Examples of yellow sublimable disperse dyes include 4- (2,2-dicyanovinyl) -3-methyl-N
-Butyl-N- (2-methoxyethyl) -aniline, 4
-(2,2-Dicyanovinyl) -3-methyl-N, N-
Bis (2-methoxyethyl) -aniline, 4- (2,2
-Dicyanovinyl) -3-methyl-N- (2-acetoxyethyl) -N-aniline and other styryl dyes; 3-cyano-6-hydroxy-1-hydroxymethyl-4-methyl-5-phenylazo-2- Pyridone, 3-cyano-
6-hydroxy-1- (3-hydroxypropyl) -4
-Methyl-5-phenylazo-2-pyridone, 3-cyano-6-hydroxy-1- (4-hydroxybutyl)-
Examples include pyridone dyes such as 4-methyl-5-phenylazo-2-pyridone.

Examples of magenta sublimable disperse dyes include p-
(1,2,2-Tricyanovinyl) -N, N-dimethylaniline, p- (1,2,2-tricyanovinyl)-
Styryl dyes such as N, N-diethylaniline and p- (1,2,2-tricyanovinyl) -N, N-didipropylaniline; 1-amino-4-hydroxy-2-mercaptoanthraquinone, 1-amino -4-hydroxy-2
-Cyclohexylthioanthraquinone, 1-amino-4
1-such as hydroxy-2-methylthioanthraquinone
Amino-4-hydroxyanthraquinone dye; 2-
(P-Dimethylaminophenylazo) -5-nitro-
1,3-thiazole, 2- (p-diethylaminophenylazo) -5-nitro-1,3-thiazole, 2- [p
-Ethyl (2-methoxyethyl) aminophenylazo]
5-Nitrothiazole dyes such as -5-nitro-1,3-thiazole; 2-methylthio-5- [2'-methyl-
4 '-(N, N-dimethylamino) -phenylazo]-
1,3,4-thiadiazole, 2-methylthio-5-
[2'-methyl-4 '-(N, N-diethylamino)-
Phenylazo] 1,3,4-thiadiazole, 2-methylthio-5- [2'-methyl-4 '-{N, N-di-
(Iso) -purupylamino} -phenylazo] -1,
2-alkylthio-1, such as 3,4-thiadiazole,
3,4-thiadiazole azo dye; 3-methylthio-
5- [4 '-(N, N-dimethylamino) -phenylazo] -1,2,4-thiadiazole, 3-ethylthio-
5- [4 '-(N, N-dimethylamino) -phenylazo] -1,2,4-thiadiazole, 3-methylthio-
Examples thereof include 3-alkylthio-1,2,4-thiadiazole-based azo dyes such as 5- [4 ′-(N, N-diethylamino) -phenylazo] -1,2,4-thiadiazole.

As cyan sublimation disperse dyes, 1,4
-Bis (methylamino) -5,8-naphthoquinone, 1,
4-bis (ethylamino) -5,8-naphthoquinone, 1
-Methylamino-4-ethylamino-5,8-naphthoquinone, 1-methylamino-4- (n) -butylamino-
Naphthoquinone dyes such as 5,8-naphthoquinone; 1-amino-2-methoxycarbonyl-4- (3-methoxypropyl) aminoanthraquinone, 1-amino-4 (3-
Anthraquinone dyes such as ethoxypropyl) amino-2-methoxycarbonylanthraquinone; 2- (2-acetylamino-4-diethylaminophenylazo) -3
-Cyano-5-nitrothiophene, 3-cyano-2-
(4-diethylamino-2-propionylaminophenylazo) -5-nitrothiophene, 2- (p-diethylaminophenylazo) -3,5-dinitrothiophene,
3-Cyano-2- (8-ethylamino-2-methyl-5
-Quinolinylazo) -5-nitrothiophene, 3-cyano-2- (2-methyl-8-octylamino-5-quinolinylazo) -5-nitrothiophene, and other heterocyclic azo dyes; 4- (4-diethylaminophenyl) Imino)-
2-propionylamino-1,4-benzoquinone, 2-
Indoaniline dyes such as acetylamino-4- (4-diethylamino-2-methylphenylimino) -1,4-benzoquinone and 2-butyrylamino-4- (4-diethylaminophenylimino) -1,4-benzoquinone are available. Can be mentioned.

Black can be expressed by using all of the three hues of yellow, magenta and cyan described above, but black sublimation disperse dyes may be appropriately used for emphasis and are limited in the present invention. Not something to do.

The sublimable disperse dye used in the present invention is dissolved or dispersed in water or a water-soluble organic solvent which is also a medium for dispersing the microcapsules. Examples of the water-soluble organic solvent are shown below, but the invention is not limited thereto.

As the water-soluble organic solvent, methyl alcohol, ethyl alcohol, n-propyl alcohol, n-
Butyl alcohol, sec-butyl alcohol, ter
C1-C4 alkyl alcohols such as t-butyl alcohol and isopropyl alcohol; amides such as dimethylformamide and dimethylacetamide; acetone,
Ketones or ketone alcohols such as diacetone alcohol; ethers such as tetrahydrofuran and dioxane;
Polyalkylene glycols such as polyethylene glycol and polypropylene glycol; ethylene glycol,
Alkylene glycols having 2 to 6 alkylene groups such as propylene glycol, butylene glycol, triethylene glycol, 1,2,6-hexanetriol, thiodiglycol, hexylene glycol and diethylene glycol; glycerin, ethylene glycol, methyl ether, Examples thereof include lower alkyl ethers of polyhydric alcohols such as diethylene glycol methyl (or ethyl) ether, triethylene glycol and monomethyl ether.

Among many of these water-soluble organic solvents,
Preferred are polyhydric alcohols such as diethylene glycol and lower alkyl ethers of polyhydric alcohols such as triethylene glycol monomethyl ether and triethylene glycol monoethyl ether.

As described above, the dispersion medium composed of the sublimable disperse dye and the polyester resin may be mixed with a heat-fusible substance compatible or incompatible with the polyester. Examples of the substance include plant waxes such as rice wax, candelilla wax, and carnauba wax, animal waxes such as lanolin, beeswax, and cerax wax, mineral waxes such as montan wax, paraffin wax, microcrystalline wax, and oxidized wax. , Chlorinated paraffin wax, ricinoleic acid amide, palmitic acid amide, oleic acid amide, 12
-Hydroxystearic acid, distearyl ketone, synthetic waxes such as ethylenebisstearic acid amide, higher alcohols such as palmityl alcohol, stearyl alcohol, cetyl alcohol, low molecular weight polyethylene, low molecular weight polystyrene, polyamide resin, polyacrylic resin,
Examples thereof include synthetic resins such as polyvinyl acetate and ethylene-vinyl acetate copolymer.

In the ink jet recording ink of the present invention, a wetting agent such as glycols, glycol ethers, amides and pyrrolidones, a binder and an interface are added to a medium in which microcapsules containing a sublimable disperse dye are dispersed. Addition of additives such as an activator, an oxygen absorber, a physical property adjusting agent, a charge adjusting agent, a fungicide, and a chelating agent is not limited in any way.

The recording medium of the present invention has at least one ink receiving layer provided on the surface of a support.

As the support, high-quality paper, coated paper, photographic base paper (RC paper), synthetic paper, foamed PET film, plastic film and the like can be appropriately used and are not particularly limited.

As the ink receiving layer provided on the surface of the support,
It is made of a material containing an inorganic or organic pigment and a water-soluble polyester resin as a main component. The water-soluble polyester resin is most preferable for fixing the sublimable disperse dye,
In addition, polyacrylic ester resin, polycarbonate resin, polyvinyl acetate resin, styrene acrylate resin, vinyl toluene acrylate resin, polyurethane resin, polyamide resin, urea resin, polycaprolactone resin, polystyrene resin, polyvinyl chloride resin, polyacrylate resin, Examples thereof include polyacrylonitrile resin.

Examples of the inorganic or organic pigments used in the present invention include light calcium carbonate, heavy calcium carbonate, kaolin, talc, calcium sulfate, barium sulfate, titanium oxide, zinc oxide, zinc sulfide, zinc carbonate and satin. White inorganic pigments such as white, aluminum silicate, diatomaceous earth, calcium silicate, magnesium silicate, synthetic amorphous silica, aluminum hydroxide, alumina and lithopone, and styrene plastic pigments, acrylic plastic pigments, microcapsules, urea resin pigments. There are organic pigments such as.

In addition to the water-soluble polyester resin used in the present invention, other adhesives include, for example, polyvinyl alcohol, oxidized starch, etherified starch, cellulose derivatives such as carboxymethyl cellulose, hydroxyethyl cellulose, casein, gelatin, soybean. Protein, silanol-modified polyvinyl alcohol, maleic anhydride resin, usual styrene-butadiene copolymer, methyl methacrylate-butadiene copolymer and other conjugated diene-based copolymer latex, acrylic acid ester and methacrylic acid ester polymer or Acrylic polymer latex such as copolymer, vinyl polymer latex such as ethylene vinyl acetate copolymer, or functional group-modified polymer latex with functional group-containing monomer such as carboxyl group of these various polymers, melamine A water-based adhesive such as a thermosetting synthetic resin type such as oil and urea resin, and a synthetic resin type adhesive such as polymethylmethacrylate, polyurethane resin, vinyl chloride-vinyl acetate copolymer, polyvinyl butyral, and alkyd resin, alone or in combination. Used.

Other additives include pigment dispersants, thickeners, fluidity improvers, defoamers, foam suppressors, mold release agents, foaming agents, penetrants, colored dyes, colored pigments, fluorescent whitening agents. An agent, an ultraviolet absorber, an antioxidant, an antiseptic, an antifungal agent, a water resistant agent, a wet paper strength enhancer, a dry paper strength enhancer and the like can be appropriately added.

In the present invention, an ink receiving layer is provided on the surface of a support, and a sheet obtained by coating an ink receiving layer on the surface of a support can be used as it is as a recording medium of the present invention. It is also possible to impart surface smoothness through a roll nip under heating and / or pressure with a gloss calendar or the like. In this case, excessive processing by the super calender reduces the ink absorbability due to the voids between the particles formed at the corners, and thus the processing degree may be limited.

[0042]

The inkjet recording ink of the present invention comprises microcapsules containing a recording composition in which a sublimable disperse dye is dissolved or dispersed in at least one of water, a water-soluble organic solvent and a polyester resin in a medium. The microcapsules containing the respective hues of yellow, magenta, cyan, and black are used as the sublimable disperse dye to record a full-color image. or,
This is a recording method in which the ink for inkjet recording of the present invention is recorded on a recording medium, and the recording portion is subjected to a pressure treatment to destroy the microcapsules or to perform heat treatment in addition thereto.
In a full-color recording image using a conventional inkjet recording ink, the inks of different hues do not sufficiently mix and are present as overlapping of fine ink dots. By destroying the microcapsules, the inks of different hues mix well on the ink-receiving layer of the recording medium. Therefore, the recorded image has a high image density and excellent chromaticity. Further, it is considered that the heat treatment after the pressurization causes the dot boundary surface of the image to be blurred and enhance the gradation.

[0043]

EXAMPLES The present invention will be specifically described below with reference to examples.

Example 1 1. Production of Microcapsules Microcapsules of polyurea wall material containing a sublimable disperse dye were produced as follows. 90 parts of ion-exchanged water,
4- (2,2-dicyanovinyl) -3-methyl-N as a yellow sublimable disperse dye composed of a styryl dye
1-butyl-N- (2-methoxyethyl) -aniline
0 part was dispersed, and 1.5 parts of hexamethylenediamine was dissolved therein to prepare a microcapsule inclusion (core substance). On the other hand, as a hydrophobic substance that emulsifies the core substance, 7.5 parts of polyisocyanate, which is an adduct of trimethylolpropane and tolylene diisocyanate, is added to butyl acetate 3 parts.
It was dissolved in 00 parts, 1 part of sorbitan tristearate was further added as an emulsifier, and the mixture was stirred until uniform. A prepared core substance was gradually added to the prepared hydrophobic substance with stirring to emulsify it. When the average particle size of the emulsified particles reached 8 μm, the system temperature was gradually raised to 35 ° C. and the reaction was carried out for 3 hours. After the reaction, it was confirmed by an optical microscope that microcapsules having a polyurea wall film having an average particle diameter of 8 μm, which was almost the same as emulsified particles, were formed.
Then, the microcapsules dispersed in butyl acetate were added to a mixed solution of 320 parts of water and 80 parts of ethylene glycol, and butyl acetate was removed under reduced pressure to remove about 2
A 5% aqueous dispersion of microcapsules was obtained. The microcapsule water-soluble dispersion itself can be used as the ink for inkjet recording of the present invention.

A 5-nitrothiazole dye consisting of 2- (p-diethylaminophenylazo) -5-nitro-1,3-thiazole is used as a magenta sublimable disperse dye in place of the yellow sublimable disperse dye. Microcapsules were produced in the same manner as described above, except that an anthraquinone dye consisting of 1-amino-2-methoxycarbonyl-4- (3-methoxypropyl) aminoanthraquinone was used as the cyan sublimation disperse dye. ..

2. Manufacture of Recording Medium for Inkjet Recording Using neutral paper having a basis weight of 70 g / m ² as a base paper, 80 parts of synthetic amorphous silica (Fineseal X-37B, manufactured by Tokuyama Soda Co., Ltd.), light calcium carbonate ( Callite KT, manufactured by Shiraishi Calcium Co., Ltd., 20 parts, water-soluble polyester resin (Vylonal, manufactured by Toyobo Co., Ltd.) 40 parts, cationic resin (SUMIREZ RESIN 1001, manufactured by Sumitomo Chemical Co., Ltd.) 30 parts were mixed in a coating liquid of 15% in air It was coated with a knife coater to a solid content of 8 g / m @ 2, and supercalendered to obtain a recording medium.

3. Printing test The ink for inkjet recording obtained in the above 1 was used to print on the recording medium of the above 2 and evaluated. As a printing device, an inkjet printer manufactured by Sharp Corporation (IO-720) was used, and a full-color image input by a scanner was printed on a recording medium in the order of yellow, magenta, and cyan inks. Pass the recording medium of the recorded printed image through a super calendar, destroy the microcapsules in the image area,
Then, printing was completed by passing through a hot roll set at 100 ° C. The printed image area obtained here, for example, the portions composed of respective hues, red, green, and blue, which are recorded in double colors with two-color inks of yellow and magenta, yellow and cyan, magenta and cyan, are observed using an optical microscope. did. It was confirmed that yellow and magenta were mixed and yellow was present in the portion where the yellow and magenta inks were recorded in a double color. Similarly, green by yellow and cyan and blue by magenta and cyan could be observed. In addition, the print density is high at the boundary portion of each hue, and density gradation is exhibited from the center of the print dot diameter toward the outer diameter.

Comparative Example 1 The ink for ink jet recording prepared in Example 1 was used to print on a recording medium in the same manner as in Example 1. Here, without applying pressure treatment with the super calendar of Example 2,
I left it as it was. As a result, when compared with Example 1, the yellow microcapsules and the magenta microcapsules were directly retained as dots in the yellow and magenta heavy color recording portion, and the print density was low and gradation was not obtained. It was

Example 2 1. Production of Microcapsules Melamine-formaldehyde wall material microcapsules containing a colored pigment were produced as follows. Softening point 90 ° C
While heating and melting 90 parts of the polyester resin of No. 1, 10 parts of 1,4-bis (methylamino) -5,8-naphthoquinone as a cyan sublimable disperse dye composed of a naphthoquinone dye is added to be uniform. And dispersed to prepare a microcapsule inclusion (core substance). This was added to 120 parts of a 5% aqueous solution of pH 4.0 in which a styrene-maleic anhydride copolymer was dissolved together with a small amount of sodium hydroxide, and the mixture was dispersed and emulsified at a temperature of 80 ° C. Here, the emulsified particles had an average particle size of 10 μm. Separately, as a film material,
Prepare a melamine-formaldehyde initial shrinkage product.
Melamine-formaldehyde initial compaction product is melamine 10
Parts, 25 parts of a 37% aqueous formaldehyde solution, and 65 parts of water were adjusted to pH 9 with sodium hydroxide and heated to 60 ° C. to dissolve them to make them transparent. To the previously emulsified emulsion, melamine-formaldehyde initial condensed product was added, and the liquid temperature was maintained at 60 ° C. with stirring to perform microencapsulation. The average particle size of the microcapsules was about 10 μm, which was almost the same as the average particle size of the emulsified particles. The solid content concentration of the manufactured microcapsule dispersion was about 40%.

As a yellow sublimable disperse dye instead of the cyan sublimable disperse dye, a pyridone type dye consisting of 3-cyano-6-hydroxy-1-hydroxymethyl-4-methyl-5-phenylazo-2-pyridone, The same procedure as described above was repeated except that a styryl dye composed of p- (1,2,2-tricyanovinyl) -N, N-dimethylaniline was used as the magenta sublimable disperse dye. Was manufactured.

2. Preparation of inkjet recording ink To 320 parts of each of the yellow, magenta, and cyan microcapsule dispersions obtained in 1 above, 80 parts of diethylene glycol was added to prepare an inkjet recording ink.

3. Print Evaluation Using the recording medium and the printing device used in Example 1, a full-color image input by a scanner is printed on the recording medium,
This was passed through a super calendar to break the microcapsules in the image area, and then passed through a hot roll set at 100 ° C. to finish printing. The printed image was such that the microcapsule inclusions of each hue were melted by heat, penetrated and adhered to the ink receiving layer, and had fixability. It is possible to obtain the same result as the observation under the optical microscope of Example 1, and to obtain a high print density,
Moreover, an image with density gradation could be obtained.

Comparative Example 2 Using the ink jet recording ink prepared in Example 2, printing was performed on a recording medium in the same manner as in Example 2. Here, the pressure treatment by the super calendar of Example 2 and the heat treatment by the hot roll were not performed, and they were left as they were. As compared with Example 2, the microcapsules of each hue were not destroyed, so the dot diameter was maintained, and the print image had low print density and poor gradation.

[0054]

The present invention relates to an ink jet recording ink containing microcapsules containing a sublimable disperse dye in a medium composed of water or a water-soluble organic solvent, and a recording method therefor. In recording, it is possible to obtain a printed image having high printing density and excellent gradation of a full-color image.

Claims (5)

[Claims] 1. In an inkjet recording ink containing microcapsules in a medium composed of water or a water-soluble organic solvent, the inclusion of the microcapsules is at least one of water, a water-soluble organic solvent, and a polyester resin. A recording composition in which a sublimable disperse dye is dissolved or dispersed, wherein the sublimable disperse dye is composed of each hue of yellow, magenta, and cyan, and the sublimable disperse dye of each hue is separately encapsulated in a microcapsule. Ink for ink jet recording characterized by being formed. 2. A yellow sublimable disperse dye selected from the group consisting of styryl dyes and pyridone azo dyes.
The magenta sublimable disperse dyes are styryl dyes, 1-amino-4-hydroxyanthraquinone dyes, 5-nitrothiazole azo dyes, 3-alkylthio 1,2,4-thiadiazole dyes, 2- Alkylthio-1,3,4-thiadiazole-based azo dye, which is one kind selected from the group of cyan sublimation disperse dyes,
The ink for inkjet recording according to claim 1, wherein the ink is one selected from the group consisting of naphthoquinone dyes, anthraquinone dyes, heterocyclic azo dyes, and indoaniline dyes. 3. A microcapsule inclusion is a recording composition in which a sublimable disperse dye is dissolved or dispersed in at least one of water, a water-soluble organic solvent, and a polyester resin, and the sublimable disperse dye is , Yellow, magenta, and cyan hues, the microcapsules contain the sublimable disperse dyes of the respective hues separately, and the microcapsules are contained in a medium composed of water or a water-soluble organic solvent. An ink jet recording method, characterized by performing ink jet recording on a recording medium using the ink for ink jet recording of each hue, and then subjecting the microcapsules to pressure treatment to destroy the microcapsules or heat treatment in addition thereto. .. 4. A yellow sublimable disperse dye selected from the group consisting of styryl dyes and pyridone azo dyes.
The magenta sublimable disperse dyes are styryl dyes, 1-amino-4-hydroxyanthraquinone dyes, 5-nitrothiazole azo dyes, 3-alkylthio 1,2,4-thiadiazole dyes, 2- Alkylthio-1,3,4-thiadiazole-based azo dye, which is one kind selected from the group of cyan sublimation disperse dyes,
The ink for inkjet recording according to claim 3, wherein the ink is one selected from the group consisting of naphthoquinone dyes, anthraquinone dyes, heterocyclic azo dyes, and indoaniline dyes. 5. A recording medium having at least one surface on a support surface.
6. The ink jet recording method according to claim 5, wherein the ink receiving layer is formed by coating more than one layer, and the ink receiving layer component is mainly composed of an inorganic or organic pigment and a water-soluble polyester resin.