JP2000086958A - Ink-jet recording - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve water resistance and weatherability and a water-based ink to the same level as that of a plate printing ink since a water-based ink having a composition composed of a water-soluble dye and water provides stable ink discharge due to physical properties (surface tension and viscosity) suitable for ink-jet but a defect of weak water resistance has been unable to be solved when a water-soluble dye is used as an ink colorant. SOLUTION: Ink-jet recording is carried out by using a water-based ink obtained by dissolving a leuco sulfuric ester alkali metal salt of quinone type insoluble organic coloring matter and ink dots on a material to be recorded are provided with light energy to change the organic coloring matter into an insoluble coloring matter. Consequently the durability (water resistance, light resistance and heat resistance) of printing ink is improved to the same level as that of a plate printing ink.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording method. More specifically, the present invention relates to an ink jet recording method in which a photosensitive water-soluble dye contained in ink is insolubilized by exposing an ink dot on a recording material on which ink jet recording has been performed to fix the ink.

[0002]

2. Description of the Related Art In an ink jet recording method, printing or recording of an image is performed by discharging fine droplets of ink from a nozzle and attaching the droplets to a surface of a recording material such as paper.
Various ink jet recording methods have been proposed, and a method called a continuous method is described in, for example, US Pat.
SP 3,298,030 and USP 3,596,
275. In the drop-on-demand method, a technique in which deformation of a piezo element is applied to a driving force of ink ejection is disclosed in, for example, US Pat. No. 3,946,398. An ink jet recording method for ejecting ink droplets using thermal energy is disclosed in, for example, US Pat.
1,824. Although these patent publications propose a method of ejecting ink droplets, they do not describe an ink composition suitable for ink jet recording.

However, in any of the ink jet recording methods, the ink is ejected at a high speed as fine droplets from the orifice of a fine nozzle, so that the ejection stability of the ink droplets is greatly affected by the viscosity and surface tension of the ink. You. That is, it is desirable that the viscosity of the ink be as small as possible and the surface tension of the ink be as large as possible. If the ink viscosity is high, it becomes difficult to supply ink stably to the recording head following high frequency driving in the ink chamber. In addition, when the surface tension of the ink is small, the wetting of the ink droplet on the nozzle opening becomes large, and it is difficult to fly the ink droplet in an accurate direction. Cause things to happen.

[0004] For the above reasons, aqueous inks containing water as a main solvent are generally used as ink jet recording inks. Also, a water-soluble dye as a coloring material,
For example, acid dyes, direct dyes, basic dyes and the like are used. However, the printed matter recorded with the aqueous ink containing such a water-soluble dye has a problem that the water resistance of the coloring material is low. In addition, storage stability of printed matter was insufficient due to weak light resistance.

[0005] To cope with this problem, many proposals have been made to use aqueous inks in which a pigment is dispersed (for example, Japanese Patent Application Laid-Open No. 56-147859). According to this method, although the robustness of the recorded matter can be satisfied to some extent, when it is used as an ink jet ink, a problem of nozzle clogging occurs.

[0006] In order to avoid the above-mentioned inconvenience, after ink jet recording using an aqueous ink containing a water-soluble dye,
A method of insolubilizing an ink dye on a recording material has been proposed, and an aqueous ink containing a soluble vat dye has been proposed as a specific example of such an ink (for example, Japanese Patent Publication No. 7-29777). ).

Sulfate sodium salt of a vat dye leuco compound, which is a main component of a soluble vat dye, has photosensitivity and is photochemically oxidized by light irradiation to regenerate the original insoluble vat dye. Is conventionally known. For example, British Patent Nos. BP354,575 and BP43
No. 1,072 proposes a method for obtaining a wet color photograph utilizing this property. Also, Japanese Patent Laid-Open No. Sho 50-12
Japanese Patent No. 3991 proposes a method of printing a photographic pattern on a textile using the photosensitivity of a soluble vat dye.

The vat dye leuco compound and its sodium sulfate ester salt absorb ultraviolet and visible light having a wavelength of 200 nm to 600 nm. Therefore, when irradiated with high-energy ultraviolet rays, the molecules are excited, and the insoluble vat dye is regenerated through the process shown in Chemical formula 1. In Chemical Formula 1, the color index number C.I. I. 73360 (CI Va)
4,4'-dimethyl- corresponding to t Red 1).
Leuco compound sulfate sodium salt of 6,6'-dichlorothioindigo is shown as an example.

[0009]

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Vat dyes are insoluble in water, but become water-soluble when an alkaline reducing agent is added. For example, it is reduced by caustic soda and hydrosulfite to a water-soluble leuco compound. Quinone-type organic pigments having two or more carbonyl groups in the conjugated double bond system in the molecule are similarly water-soluble. The molecular absorption spectrum of the leuco compound shifts to a shorter wavelength side compared to the original vat dye, and has an absorption in an ultraviolet wavelength region. The leuco compound is photosensitive and is oxidized immediately upon exposure to regenerate the original insoluble vat dye.

The leuco compounds of vat dyes are easily oxidized by oxygen in the air and easily return to the original vat dye, and therefore are generally unstable in the air and are inconvenient to handle. Therefore, a leuco compound which is stabilized by esterification with sulfuric acid is called a soluble vat dye and has been used for dyeing fibers. However, these soluble vat dyes were originally developed for dyeing textiles,
A dye suitable for the color tone of the ink jet recording ink as a coloring material could not be obtained.

[0012]

In order to produce a full-color image in three primary colors by the subtractive color method, dyes having clear colors of yellow, magenta and cyan are required. However, the dyes of these three primary colors are obtained as soluble vat dyes. I couldn't. That is,
In the absorption spectrum curve, the peak (maximum absorption,
(λmax) is around 430 nm, a yellow colorant has a peak (maximum absorption, λmax) around 530 nm, and a magenta colorant has a peak (maximum absorption, λmax) is 640.
A cyan coloring material near nm is required.

Further, since the photooxidation of the soluble vat dye is insolubilized through the process shown in Chemical formula 1, it is necessary to devise an insolubilization method as quickly as possible by combining efficient ultraviolet irradiation and air oxidation. is there. For example, Examples 6 to 1 of Japanese Patent Publication No.
0, small UV with wavelength of 365 nm
The lamp required an exposure time of about 10 minutes or more.
Since this is too slow for an ink jet printer, it is necessary to be able to insolubilize it at least at a speed synchronized with the printing speed of the ink jet recording head. Specifically, the ink dot on the recording material is
It has been required to increase the photooxidation rate of the coloring material so that it can be insolubilized in 60 seconds.

As described above, after the ink jet recording is performed using the aqueous ink, the color material on the recording material is irradiated with light energy (for example, irradiation of ultraviolet light or laser) to be insolubilized at a high speed, and the ink is fixed. The purpose is to obtain the same level of printing ink durability as the printing ink.

[0015]

A water-soluble coloring material required for the above three primary colors was prepared by the following method. A method for producing a soluble vat dye from a vat dye, that is, a general method for synthesizing a vulcanized dye leuco compound sulfate, is as follows. The liquid temperature is lowered to 20 ° C. while slowly adding 100 parts of chlorosulfonic acid at 15-20 ° C. to 500 parts of dried pyridine under cooling.
Over about 2 hours to make the chlorosulfonic acid / pyridine adduct. Then, 100 parts of the dried vat dye base material is added thereto, and 40 parts of pure iron powder is added thereto all at once while stirring, so that the reaction mixture is heated to 50 to 6 without heating.
Reach 0 ° C. Stirring is continued as it is, and the esterification reaction is completed in about 6 hours. Thereafter, the reaction mixture is poured into ice water containing about 6 times the amount of 5% caustic soda and stirred.
Several drops of an antifoaming agent are added, and pyridine at 30 to 35 ° C. is recovered by distillation under reduced pressure. After collecting the pyridine, the total amount is made up to about 3000 parts by adding water and the mixture is heated to 80 ° C. and filtered after 2 hours. The residue is iron, iron oxide, etc., which is discarded.
After the filtrate is concentrated by distillation under reduced pressure, a sulfate salt of a vat dye leuco compound is obtained by a salting out method. Dimethylaniline may be used instead of the above pyridine,
Copper powder may be used in place of the iron powder.

According to the above-mentioned method, photosensitive water-soluble dyes of yellow, magenta and cyan to be used as ink coloring materials in the ink jet recording method of the present invention were obtained. Each of these dyes is listed in Examples 1-3

Although not a quinone type dye, only cobalt phthalocyanine among the phthalocyanine dyes is different from other metal phthalocyanines and can be solubilized by an alkaline reducing agent as if it were a quinone type vat dye. Particularly, a partially sulfonated cobalt phthalocyanine is used in the color index for C.I.
I. It has been classified as Vat Blue 29 (CI. 74140), and was made water-soluble in the form of a sodium salt in Chemical Formula 2. This water-soluble coloring material can be insolubilized by exposure to ultraviolet light. Cobalt phthalocyanine can be used as a coloring material for vivid cyan ink.

[0018]

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The black ink was prepared by the method described in Example 4. In addition to these, a black ink coloring material can be obtained by various examples of dyes. The photosensitive water-soluble coloring materials which can be used in the ink jet recording method of the present invention, including the dyes for blending black, are listed in the following Chemical Formula 3.
All of these photosensitive water-soluble coloring materials can be prepared from a precursor insoluble dye by the above-mentioned method. In addition, these photosensitive water-soluble coloring materials can be insolubilized by ultraviolet irradiation.

[0020]

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Until now, ordinary mercury discharge lamps have been used as UV lamps. Mercury discharge lamps are also simply called mercury lamps or mercury lamps. The emitted light of the mercury lamp has a discontinuous spectrum, and the emission spectrum varies depending on the mercury vapor pressure in the discharge tube. Low pressure mercury lamp (mercury vapor pressure P = 0.0
At 1 mmHg, ultraviolet rays having a wavelength of 254 mm are mainly emitted. Since the low-pressure mercury lamp has a low mercury vapor pressure, the lamp power cannot be increased to about 1 W / cm or more, and only a low-power lamp can be obtained. However, ultraviolet light having a wavelength of 254 nm is efficiently emitted. Low-pressure mercury lamps are used as germicidal lamps. In contrast, a high-pressure mercury lamp (mercury vapor pressure P
= 760 mmHg), the spectrum shifts to the longer wavelength side, and the wavelengths are mainly 365 mm, 405 mm, and 436 mm.
Etc. are emitted. Ultra-high pressure mercury lamp (mercury vapor pressure P = 3
0 atm) emits much visible light and is not suitable as a UV lamp. Table 1 below shows the emission spectra of these mercury lamps.

[0022]

[Table 1]

It has been found that an ultraviolet fluorescent lamp is suitable as a UV lamp for exposure used in the present invention. Although the ultraviolet fluorescent lamp has a slight difference depending on the composition of the fluorescent substance coated on the wall of the discharge tube (quartz glass tube), it has a continuous spectrum mainly in a wavelength region of 300 to 400 nm, and has relatively low power consumption. It has been found that the amount of the coloring material of the ink dot can be insolubilized by the amount. An ultraviolet fluorescent lamp is a low-pressure mercury lamp in which a fluorescent substance is coated on the inner wall of a discharge tube (quartz glass tube), and the fluorescent substance has a wavelength of 300.
It emits ultraviolet light in the region of 400 nm.
The structure of the discharge tube of an ultraviolet fluorescent lamp is the same as that of a low-pressure mercury lamp. Low-pressure mercury lamps are also called germicidal lamps. An example of the emission spectrum of an ultraviolet fluorescent lamp is shown in Table 2 below in comparison with the spectrum of a low-pressure mercury lamp.

[0024]

[Table 2]

It has also been found that when a fluorescent lamp for ultraviolet light and a germicidal lamp are used together to form a so-called hybrid lamp system, the insolubilization of the coloring material can be further accelerated.

Normally, plain paper is used as a recording material, and the plain paper contains 10 to 100% by weight of acid clay.
It was found that the use of the added paper as the recording paper greatly accelerated the insolubilization of the coloring material. This is considered to be because the property of the acid clay as a solid acid promotes the hydrolysis of the vulcanizing dye leuco compound sulfate as the coloring material. Acid clay is sometimes used in conventional papermaking technology as an additive for improving whiteness and preventing bleeding.

Acid clay is also used in the production of thermal paper used as recording paper for thermal printers, and is coated on paper together with leuco dyes and binders as coloring materials to produce so-called coated paper. .
In the case of thermal paper, the surface must be smooth to improve the heat conduction from the thermal head, so that it becomes a coated paper (coated paper). On the other hand, in the ink jet recording method, since the recording head ejects ink and records on paper in a non-contact manner, the surface of the paper does not need to be smooth, and the pulp fiber is exposed on the surface and is similar to plain paper which has fluff. It may be a paper having a breathable appearance. Plain paper has a much lower production cost than coated paper, and is easy to recycle.

In a conventional precision printing press, a vacuum (reduced pressure) is sometimes used as a method of fixing a recording material to prevent color misregistration. In the ink jet recording method of the present invention, it has been clarified that the use of vacuum (reduced pressure) as a means for fixing the recording material sheet further accelerates the insolubilization of the coloring material. This is because a small amount of ozone is generated around the discharge tube by the ultraviolet radiation of the UV lamp. It is considered that the ozone is attracted onto the paper by the bakuchim (decompression) and promotes the oxidation of the coloring material.
The distance between the UV lamp and the paper is 1 to 2 cm. Since the UV lamp is covered with a reflective lamp hood, the air containing ozone can efficiently pass through the paper by vacuum (decompression) to oxidize the coloring material. Used.

As described above, the coloring material was insolubilized within 10 to 60 seconds by the UV lamp having an output of 50 to 300 W (watt), and the ink could be fixed. The speed of photooxidation of each of the photosensitive water-soluble coloring materials is not uniform and varies depending on the color. Yellow colorants are fast, black and cyan colorants are slow. The magenta colorant is in between.

After ink jet recording using the aqueous ink containing the soluble vat dye (photosensitive water-soluble coloring material) obtained as described above, ultraviolet light was irradiated by a hybrid lamp using a combination of an ultraviolet fluorescent lamp and a germicidal lamp. FIG. 1 shows a cross section of an apparatus embodying an ink jet recording method for insolubilizing a coloring material by irradiation.

[0031]

FIG.

In FIG. 1, an ink jet recording head 1 is located immediately above a rotary drum 2 and is provided for yellow (Y), magenta (M), cyan (C), and black (Bk) necessary for recording a full-color image. The recording heads for each color ink are arranged in order from the left. The rotating drum 2 has an infinite number of pores on the surface of the cylinder, and is rotated clockwise by the rotating shaft 3, and its rotation speed is synchronized with the printing speed of the recording head. The inside of the rotary drum 2 is a decompression chamber 4, which is connected to an intake pump 8 via an intake pipe 5 from an intake port 5 inside the rotary shaft 3. The paper 14 supplied from the paper feed port 12 is attracted to the surface of the rotary drum 2 by the suction force of the decompression chamber 4 and is fixed on the drum. When the paper rotates below the recording head 1, black ink (Bk) is first recorded on the paper, and the paper is further rotated and the UV
It is exposed by a lamp. The UV lamp is a hybrid lamp system in which ultraviolet fluorescent lamps 9 and germicidal lamps 10 are alternately arranged. The lamp hood 11 reflects the ultraviolet light for effective use. The ozone generated around the lamp is passed through the decompression chamber 4 inside the drum without being escaping to the outside, so that the ink on the paper is absorbed. Has the effect of remarkably accelerating the photo-oxidation. The rotating drum makes one revolution, and then cyan ink (C) is recorded. In this way, the drum rotates four times to sequentially record magenta (M) and yellow ink (Y). The black ink having a low photo-oxidation rate is given an exposure time of four rotations and is sufficiently insolubilized. After the drum makes four rotations, the exhaust pressure valve 7 opens and the recording paper 15 adsorbed on the drum surface
Is taken out of the paper discharge port 13.

As described above, the basic physical properties required for the ink jet recording ink are that the viscosity is as small as possible and the surface tension is as large as possible. Therefore,
Most preferably, the ink composition is a simple one in which the dye is simply dissolved in water. This is because adding an excessive additive inevitably lowers the surface tension and also increases the viscosity. As the water content of the ink evaporates from the nozzle opening of the recording head, the dye component in the ink may precipitate and the nozzle may be clogged. Addition of a high boiling polar organic solvent such as N-methylpyrrolidone (NMP) or dimethylimidazolidinone (DMI) to the ink can prevent nozzle clogging. However, on the other hand, there has been a problem that the water resistance of printing is reduced. It has been difficult to solve this dilemma with conventional aqueous inks. In the aqueous ink of the present invention, since the coloring material changes to water-insoluble, the amount of the high-boiling-point polar organic solvent to be added can be greatly increased, so that the problem of nozzle clogging due to evaporation of the ink solvent does not occur.

The water resistance and light fastness of recorded images and prints obtained by the ink jet recording method of the present invention are the same as those of conventional water-soluble dyes (direct dyes, acid dyes, basic dyes).
And the durability of the printed matter is at the same level as that of letterpress printing ink. The ink jet recording method of the present invention can be applied not only to paper as a recording material but also to textiles such as cotton, silk, wool, and nylon, leather, and nonwoven fabric.

Finally, noteworthy properties of the ink used in the present invention will be described. The powder of the vat dye leuco compound sulfate is stable in the air and does not deteriorate after storage for several years if stored in a closed container. However, the aqueous solution gradually decomposes, and the life as an ink is one to two weeks. This is because the ester bond of the sulfate salt of the leuco compound is hydrolyzed. A method of dissolving the dye in a non-aqueous solvent (for example, the above-mentioned high boiling point polar solvent) to prepare a concentrated ink, and diluting with water at the time of ink jet recording to produce an aqueous ink containing a coloring material of a required concentration, or A method of directly dissolving the dye powder in a water / organic solvent mixture to prepare an aqueous ink containing a coloring material of a required concentration can be considered. Also, if the ink is left in the nozzle of the recording head for a long period of time, oxygen in the air may dissolve through the nozzle opening, and the water-soluble dye may be oxidized and become insoluble, resulting in clogging of the nozzle. There is.
Therefore, when the ink jet recording is completed, it is necessary to clean the inside of the recording head, and it is desirable to wash the ink inside the nozzles with water. Next, the present invention will be described more specifically with reference to examples. All parts or percentages in the examples are based on weight. FIG. 2 is a cross-sectional view of the apparatus used for the printing test and the exposure test described in Example 5.

[0036]

Example 1 150 g of chlorosulfonic acid was gradually added to 750 g of pyridine at 15 to 20 ° C. over about 2 hours to prepare a pyridine-chlorosulfonic acid adduct. At a temperature of 20 to 25 ° C, an insoluble dye having the following chemical structural formula (color index number CI Vat Yellow 11 /
Color index structure number C.I. I. 70405) 15
0 g was added and stirring was continued for a while. Thereafter, 100 g of pure iron powder was added at a time and stirring was continued. The temperature of the reaction mixture rose to 55 ° C,
And stirred at this temperature for 3 hours to complete the esterification reaction. The reaction mixture was poured into 5 liters of a 5% aqueous sodium hydroxide solution for neutralization. The released pyridine was recovered by distillation at 28 to 30 ° C under reduced pressure.
The residue was filtered to remove residues such as iron oxide. The filtrate was evaporated under reduced pressure and concentrated, and sodium chloride was added for salting out. The resulting dark red-brown precipitate was a photosensitive water-soluble dye represented by the following chemical structural formula, and when irradiated with ultraviolet rays, produced a clear greenish-yellow insoluble dye. This photosensitive water-soluble dye was used as a photosensitive water-soluble yellow coloring material A and used for preparing an evaluation test ink described below:

[0037]

Embodiment 2 Color index structure number C.I. 1.70
400, C.I. I. 67300, C.I. I. 60530,
C. I. 60605, C.I. I. 67810, C.I. I. 7
3365, C.I. I. 73385, C.I. I. 73905,
The following photosensitive water-soluble yellow coloring materials B, C, D, and E were used as starting materials in the same manner as in the synthesis method of Example 1.
And photosensitive water-soluble magenta coloring materials F, G, H, and I were obtained. These colorants were used in preparing the evaluation test inks described below:

[0038]

Embodiment 3 Color Index Structure Number I. 67
910, and C.I. I. Using 67915 as starting materials, the following photosensitive water-soluble cyan coloring materials J and K were obtained in the same manner as in the synthesis method of Example 1. However, copper powder was used instead of iron powder. These colorants were used to prepare the evaluation test inks described below:

[0039]

Example 4 The following insoluble dye mixtures (L), (M),
Using (N) and (O) as starting materials respectively, the following four photosensitive water-soluble black coloring materials L, M, N and O were prepared in the same manner as in the synthesis method described in Example 1: The four photosensitive water-soluble black coloring materials thus obtained were used in the preparation of the evaluation test inks described below:

[0040]

Example 5 Aqueous ink for ink jet recording was prepared by using the following 15 ink formulations using the 15 photosensitive water-soluble coloring materials A to O obtained in Examples 1 to 4 above: *) The ink containing the photosensitive water-soluble coloring material A was designated as ink (A). Similarly, inks containing the photosensitive water-soluble coloring materials B to O were prepared from inks (B) to (O). However, only black color material is 6g / 100m
1 concentration. Photosensitive aqueous ink (A) prepared above
(O) was filled in each ink bottle, and the ink bottle was loaded in a commercially available ink jet printer having a piezo type recording head, and a 2 cm × 10 cm area was solid-printed on paper.
After the ink jet recording, each solid-printed recording paper is placed on a suction table provided with a decompression chamber below a substrate having many pores, and is fixed with a vacuum (decompression) with a UV lamp (20-watt ultraviolet fluorescent light). Exposure was performed using a lamp FL20SB (manufactured by Matsushita Electric Industrial Co., Ltd. and a 15-watt germicidal lamp). The exposure time was 50 seconds. The distance between the UV lamp and the recording paper was about 1 cm. Evaluation method of ink fixing speed based on the above test results : A solid printed matter recorded by ink jet recording on plain paper by the above test method was exposed under outdoor direct sunlight for half a day to completely develop a color, and the color density was fixed at 100% ink. The product was used as an evaluation standard. Since the coloring material insolubilization and color development occur simultaneously in the photosensitive aqueous ink of the present invention, the color fixing density was measured with a colorimeter to determine the ink fixing rate. Explanation of reference numerals in the table : ○: ink fixing rate of 90 to 100% Δ: ink fixing rate of 50 to 89% ×: ink fixing rate of 49% or less

[0041]

Example 6 Test of light fastness, water fastness and heat resistance Using the solid printed matter (100% colored) obtained in Example 5, a test of light fastness, water fastness and heat fastness was carried out. As a comparative example, solid printed matter by a color laser printer was tested and compared under the same conditions. Light fastness test : After irradiation for 10 hours with a fadeometer (carbon arc discharge lamp), discoloration was evaluated and judged. Water resistance test : The test piece was immersed in hot water (60 ° C.) (for 1 minute), and it was visually determined whether or not the coloring material eluted. Heat resistance test : A blank piece of paper was placed on the test piece, an iron at 130 ° C. was placed thereon, and after 30 seconds, it was visually determined whether the color had transferred to the blank piece of paper.

[0042]

The ink durability of the printed matter by the ink jet recording method of the present invention is the same as that of letterpress printing ink.
The heat resistance of the printing ink is superior to that of the electrophotographic toner. Therefore, it can be used for commercial and commercial digital printing ink jet printers. It is also suitable for an ink jet printer that prints public documents and business documents where long-term storage is important. Since the life of the ink is as short as one to two weeks, there is an inconvenience that the operation of preparing the ink is required before the ink jet printer is operated. This ink preparation is a simple task of merely dissolving the powder dye in water, and does not cause a major problem in business and commercial printing because there are maintenance workers.

[0043]

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of an apparatus embodying an ink jet recording method of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Ink jet recording head 2 ... Rotary drum 3 ... Rotary shaft 4 ... Decompression chamber 5 ... Intake port 6 ... Intake pipe 7 ... Exhaust pressure valve 8 ... Suction pump 9 ... Fluorescent lamp for ultraviolet light 10 ... Sterilizing lamp 11 ... Lamp hood 12 ... Paper feed port 13 ... Paper discharge port 14 ... Paper 15 ... Recording paper

Claims (6)

[Claims] 1. An ink jet recording method in which water as a main ink solvent contains an aqueous ink containing any of photosensitive water-soluble coloring materials having the following chemical structural formula. And printing the yellow dot and / or recording the image by insolubilizing the coloring material to give an ink jet recording method: (However, M in the formula represents sodium, potassium or lithium) 2. An ink jet recording method in which water as a main ink solvent is an aqueous ink containing any of photosensitive water-soluble coloring materials having the following chemical structural formula, and then the ink on the recording material is irradiated with light energy. Ink jet recording method for insolubilizing the coloring material and printing magenta dots and / or recording an image. (However, M in the formula represents sodium, potassium or lithium) 3. An ink jet recording method in which water as a main ink solvent is water-based ink containing any of photosensitive water-soluble coloring materials having the following chemical structural formula, and then the ink on the recording material is irradiated with light energy. Ink jet recording method for insolubilizing the coloring material and printing a cyan dot and / or recording an image. (However, M in the formula represents sodium, potassium or lithium) 4. After performing ink jet recording using water as a main ink solvent using an aqueous ink containing any of photosensitive water-soluble coloring materials having the following chemical structural formula, light energy is applied to the ink on the recording material. Wherein the color material is insolubilized to print a black dot and / or record an image. (However, M in the formula represents sodium, potassium or lithium) 5. The method according to claim 1, wherein said light energy is ultraviolet light emitted from an ultraviolet fluorescent lamp. Inkjet recording method: 6. The paper used as a recording material is fixed to a substrate by a suction force due to reduced pressure, and air oxidation of an ink coloring material on the paper is promoted. Ink jet recording method described in (1), (2), (3) and (4):