JP2000198958A - Ink set, ink cartridge, recording process and recorded product - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a color ink set and a color ink cartridge for providing recorded products exerting a high resistance to light, which yield printed images having a high color reproducibility, resistance to scuffing, etc., and prevent color degradation or discoloration, especially color degradation or discoloration of not only colors expressed using magenta independently but also blue colors expressed using magenta in combination with cyan, and an ink jet recording process and a recorded product using these. SOLUTION: In a color ink set having a plurality of magenta inks exerting different reflection density when recorded on recording media, at least a pale magenta ink of the plurality of magenta inks contains a pigment as a colorant, and the other inks have dyestuffs as colorants. Preferably, the pale magenta ink contains C.I. pigment red 122 as a colorant, a yellow ink contains C.I. direct yellow 132 and/or C.I. direct yellow 86 as a colorant, and a cyan ink contains C.I. direct blue 199 as a colorant.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color ink set, a color ink cartridge, a recording method using the same, and a recorded material, and more particularly to a method for performing color printing by an ink jet recording apparatus using a plurality of coloring agents. ,
The present invention relates to a color ink set, a color ink cartridge, and a recording method using the same, which are excellent in color reproducibility, abrasion resistance, and the like of a printed image, and at the same time, improve fading and discoloration deterioration.

[0002]

2. Description of the Related Art As is well known, an ink jet recording method is a printing method in which ink droplets are made to fly and adhere to a recording medium such as paper to perform printing. This printing method enables high-resolution, high-quality images to be printed quickly and easily with an inexpensive device.
Technical development is being carried out as an image forming method that can substitute for photographs.

[0003] The ink used for the ink-jet recording generally contains water as a main component, and further contains a coloring component, a wetting agent such as glycerin for the purpose of preventing clogging, and the like. As the colorant used in the ink for ink jet recording, high image quality such as saturation and color reproducibility of the colorant, a wide variety of available colorants,
Water-soluble dyes are used from the viewpoint of solubility in water and reliability such as clogging.

However, dyes are sometimes inferior in various properties such as light fastness and water fastness, and printed matter printed with the dye ink is poor in light fastness and water fastness. Since the light resistance of magenta among the color dye inks (yellow, magenta, and cyan) is weak, the hue balance after light irradiation is lost, and it looks as if the image is significantly deteriorated. Further, fading and discoloration of not only the magenta color alone but also the blue color that can be expressed by combining magenta and cyan are promoted, which greatly affects image deterioration. Further, when a dark and light ink is used to reduce the graininess in the halftone area from the highlight part, a photographic image can be obtained. However, the light (light) ink has more lightfastness than the dark ink. In the case of weak magenta, the tendency is particularly remarkable, and in a mixed color portion of magenta and cyan, fading and discoloration may occur rapidly due to light deterioration. This is considered to be due to harmful radicals or active oxygen (singlet oxygen) generated by light. The water resistance of plain paper is still not enough for plain paper, but at present, it is improved by recording paper exclusively for inkjet recording having an ink absorbing layer.

On the other hand, pigments are more excellent in light resistance and water resistance than dyes. In recent years, pigments have been studied for use as colorants for ink jet recording inks for the purpose of improving light resistance and water resistance. However, in general, since the pigment is insoluble in water, when the pigment is used in an aqueous ink, the pigment is mixed with a resin called a dispersant, and the like.
It is necessary to ensure long-term reliability as an ink in a state where the pigment is uniformly dispersed in water, but it is difficult to secure dispersion stability when all colors are pigmented. Further, when a pigment is used for an aqueous ink, unlike a case where a dye is used, it is difficult to secure abrasion resistance of a printed matter printed since the pigment remains on the surface. Further, when all colors are used as pigments, there are drawbacks in that transparency (color development) and hue are poor and color reproducibility is low.

[0006]

SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of the above problems, and has as its object to improve the color reproducibility of printed images and the abrasion resistance. At the same time, fading and discoloration deterioration are prevented, and in particular, blue fading and discoloration that can be expressed by combining magenta and cyan, as well as the magenta color alone, are prevented,
It is an object of the present invention to provide a color ink set, a color ink cartridge, an ink jet recording method using the same, and a recorded material for providing a recorded material having excellent light resistance.

[0007]

The present inventors have been studying an ink jet recording method using a color ink. Recently, the present inventors have achieved high image quality by combining a specific pigment ink and a dye ink. Simultaneous abrasion resistance and light resistance (high quality images, realization of abrasion resistance and discoloration
It has been found that discoloration deterioration can be effectively suppressed), and the present invention has been completed.

That is, in the color ink set according to the present invention, in an ink set having a plurality of magenta inks having different reflection densities when recorded on a recording medium, at least the light magenta ink among the plurality of magenta inks is used as a colorant. A pigment is contained, and the colorant of the other ink is a dye (claim 1), whereby the object can be achieved.

A color ink cartridge according to the present invention is an ink cartridge containing a plurality of magenta inks and another ink integrally or at least a part thereof independently, wherein at least a light magenta ink among the plurality of magenta inks is provided. The ink contains a pigment as a colorant, and the colorant of the other ink is a dye (claim 7), whereby the above object can be achieved.

[0010] The recording method according to the present invention, when performing color printing using a plurality of magenta inks and other inks,
At least the light magenta ink of the plurality of magenta inks contains a pigment as a colorant, and a color ink set in which the colorant of the other ink is a dye is used (claim 12). Can be achieved.

The recorded matter according to the present invention is a recorded matter on which color printing has been performed using a plurality of magenta inks and another ink, wherein at least the light magenta ink among the plurality of magenta inks is a pigment as a colorant. And recorded using a color ink set in which the colorant of the other ink is a dye (claim 13), thereby providing a recorded material that has achieved the above object.

(Operation) According to the color ink set of the present invention, in an ink set having a plurality of magenta inks having different reflection densities when recorded on a recording medium, at least the light magenta ink among the plurality of magenta inks is used. By containing a pigment as a colorant and using a dye as the colorant of the other ink, it is possible to realize inkjet recording in which a color image has high image quality, has abrasion resistance, and does not cause fading or discoloration due to light. 1).

According to the color ink cartridge of the present invention, in an ink cartridge containing a plurality of magenta inks and another ink integrally or at least a part thereof independently, at least one of the plurality of magenta inks is provided. Light magenta ink contains a pigment as a colorant,
Since the colorant of the other ink is a dye, the color image has high image quality, has abrasion resistance, can be printed without fading or discoloration due to light, and can be easily handled. 7).

According to the recording method of the present invention, when color printing is performed using a plurality of magenta inks and another ink, at least the light magenta ink of the plurality of magenta inks contains a pigment as a colorant. However, by recording using a color ink set in which the coloring agent of the other ink is a dye, the image has high image quality, has abrasion resistance, and can effectively prevent fading and discoloration deterioration. (Claim 1
2).

[0015] The recorded matter according to the present invention is a recorded matter which has been subjected to color printing using a plurality of magenta inks and another ink, wherein at least the light magenta ink of the plurality of magenta inks is a pigment as a colorant. Is recorded using a color ink set in which the colorant of the other ink is a dye, so that the recorded image has high image quality, has abrasion resistance, and has no fading or discoloration deterioration. Item 13).

As described above, in the present invention, when color printing is performed using a plurality of magenta inks and another ink, at least the light magenta ink of the plurality of magenta inks contains a pigment as a colorant. By using a dye as a colorant for other inks, it is possible to maintain good image quality such as color reproducibility, impart rub resistance to images, and to express magenta, magenta and cyan in combination with blue. The disadvantage of poor lightfastness of color can be compensated for, and fading and discoloration deterioration can also be effectively prevented.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION A color ink set according to the present invention is an ink set having a plurality of magenta inks, wherein at least the light magenta ink among the plurality of magenta inks contains a pigment as a coloring agent, The colorant is a dye. Further, according to the color ink cartridge of the present invention, in an ink cartridge containing a plurality of magenta inks and another ink integrally or at least a part thereof independently, at least one of the plurality of magenta inks is lightened. The magenta ink contains a pigment as a colorant, and the colorant of another ink is a dye. next,
Preferred embodiments of the present invention will be exemplified below, but the present invention is not limited to the following first to fourteenth embodiments, and may be appropriately changed within the scope of the matters specifying the invention. Is what you can do.

(First Embodiment) A color ink set according to the present invention is an ink set comprising a dark magenta ink, a light magenta ink, a yellow ink and a cyan ink, wherein the light magenta ink contains a pigment as a colorant. An ink set, wherein the colorant of the other ink is a dye.

(Second Embodiment) A color ink set according to the present invention is an ink set including a dark magenta ink, a light magenta ink, a yellow ink, a dark cyan ink, and a light cyan ink. An ink set containing a pigment as a colorant, wherein the colorant of another ink is a dye.

(Third Embodiment) A color ink set according to the present invention is an ink set including a dark magenta ink, a light magenta ink, a dark yellow ink, a light yellow ink, a dark cyan ink, and a light cyan ink. ,
An ink set in which a light magenta ink contains a pigment as a colorant, and the colorant of another ink is a dye.

(Fourth Embodiment) The color ink set according to the present invention is an ink set including a dark magenta ink, a light magenta ink, a yellow ink, and a cyan ink, wherein the dark magenta ink and the light magenta ink are colored. An ink set containing a pigment as an agent and a colorant of another ink being a dye.

(Fifth Embodiment) A color ink set according to the present invention is an ink set including a dark magenta ink, a light magenta ink, a yellow ink, a dark cyan ink, and a light cyan ink. An ink set in which the colorant of the light magenta ink is a pigment and the colorant of another ink is a dye.

(Sixth Embodiment) The color ink set according to the present invention is an ink set including a dark magenta ink, a light magenta ink, a dark yellow ink, a light yellow ink, a dark cyan ink, and a light cyan ink. ,
An ink set in which a dark magenta ink and a light magenta ink contain a pigment as a colorant, and the colorant of another ink is a dye.

(Seventh Embodiment) A color ink set according to the present invention is an ink set including a dark magenta ink, a light magenta ink, a dark yellow ink, a light yellow ink, a dark cyan ink, and a light cyan ink. ,
Dark magenta ink contains pigments and dyes as colorants,
An ink set in which the colorant of another ink is a dye.

(Eighth Embodiment) A color ink cartridge according to the present invention is an ink in which dark magenta ink, light magenta ink, yellow ink, and cyan ink are contained integrally or at least partly independently. An ink cartridge in which a light magenta ink contains a pigment as a colorant and the colorant of another ink is a dye.

(Ninth Embodiment) A color ink cartridge according to the present invention comprises a dark magenta ink, a light magenta ink, a yellow ink, a dark cyan ink and a light cyan ink, which are integrated or at least partly independently. An ink cartridge in which a light magenta ink contains a pigment as a colorant and a colorant of another ink is a dye.

(Tenth Embodiment) A color ink cartridge according to the present invention comprises a dark magenta ink, a light magenta ink, a dark yellow ink, a light yellow ink, a dark cyan ink and a light cyan ink, or at least one of them. In an ink cartridge containing a part independently, the light magenta ink contains a pigment as a colorant,
An ink cartridge in which the colorant of another ink is a dye.

(Eleventh Embodiment) A color ink cartridge according to the present invention is an ink in which a dark magenta ink, a light magenta ink, a yellow ink, and a cyan ink are contained integrally or at least partly independently. An ink cartridge in which a dark magenta ink and a light magenta ink contain a pigment as a colorant, and a colorant of another ink is a dye.

(Twelfth Embodiment) A color ink cartridge according to the present invention comprises a dark magenta ink, a light magenta ink, a yellow ink, a dark cyan ink, and a light cyan ink, which are integrated or at least partly independently. In the contained ink cartridge, the dark magenta ink and the light magenta ink contain a pigment as a colorant,
An ink cartridge in which the colorant of another ink is a dye.

(Thirteenth Embodiment) A color ink cartridge according to the present invention comprises a dark magenta ink, a light magenta ink, a dark yellow ink, a light yellow ink, a dark cyan ink, and a light cyan ink, or at least one of them. An ink cartridge in which a part of the ink cartridge is housed independently, wherein the dark magenta ink and the light magenta ink contain a pigment as a colorant, and the colorant of the other ink is a dye.

(Fourteenth Embodiment) A color ink cartridge according to the present invention comprises a dark magenta ink, a light magenta ink, a dark yellow ink, a light yellow ink, a dark cyan ink, a light cyan ink, or at least one of them. An ink cartridge in which a part of the ink cartridge is housed independently, wherein the dark magenta ink contains a pigment and a dye as colorants, and the colorant of the other ink is a dye.

In the first to fourteenth embodiments, the black ink is not included. However, a color ink set and a color ink cartridge including a black ink using a black dye as a coloring agent may be used. it can. Further, the color ink set and the color ink cartridge according to the first to fourteenth embodiments may be an ink set and an ink cartridge including a black ink using a black pigment as a colorant.

In the first to fourteenth embodiments,
Color ink set and color ink cartridge are 4
Although the present invention is configured as a color ink set and a color cartridge of 6 to 6 color sets, the color ink set and the color ink cartridge according to the present invention are limited to those configured as a color ink set of 4 to 6 color sets and a color cartridge. For example, a two-color color ink set, a color ink cartridge, a light magenta ink using a pigment as a colorant and a light cyan ink using a dye as a colorant, or as a colorant A light magenta ink using a pigment and a dark magenta ink using a dye as a colorant may be used.

Next, each ink used in the color ink set according to the present invention will be described in more detail. [Magenta ink] Magenta ink is used as a coloring agent.
It contains one or more of the following pigments and / or one or more of dyes. -Specific examples of pigments include CI Pigment Red 5, 7,
12, 48 (Ca), 48 (Mn), 57 (Ca), 112, 122, 209 and the like. -Specific examples of dyes include CI Direct Red 2, 4,
9, 23, 26, 31, 39, 62, 63, 72, 75, 76, 79,80, 81,
83, 84, 89, 92, 95, 111, 173, 184, 207, 211, 212,
214, 218,221, 223, 224, 225, 226, 227, 232, 233, 2
40, 241, 242, 243, 247, CI Acid Red 35, 42, 5
2, 57, 62, 80, 82, 111, 114, 118, 119, 127, 128, 13
1, 143, 151, 154, 158, 249, 254, 257, 261,263, 26
6, 289,299, 301, 305, 336, 337, 361, 396, 397, CI
Reactive Red 3, 13, 17, 19, 21, 22, 23, 24, 2
9, 35, 37, 40, 41, 43, 45, 49, 55, CI Basic Red 12, 13, 14, 15, 18, 22, 23, 24, 25, 27, 29, 35, 3
6, 38, 39, 45, 46 and the like.

The magenta ink contains at least water together with the pigment and / or dye. Further, it preferably contains an organic solvent. The organic solvent is preferably a low-boiling organic solvent, and preferred examples thereof include methanol, ethanol, n-propyl alcohol, iso-propyl alcohol, n-butanol, sec-butanol, tert-butanol, is
o-Butanol, pentanol and the like. Particularly, a monohydric alcohol is preferable.

It is preferable that the magenta ink further contains a wetting agent to prevent clogging of the nozzles of the recording head. Preferred examples of the wetting agent include diethylene glycol, polyethylene glycol, polypropylene glycol, ethylene glycol, propylene glycol, butylene glycol, triethylene glycol,
1,2,6-hexanetriol, thioglycol, hexyleneglycol, glycerin, trimethylolethane, trimethylolpropane, urea, 2-pyrrolidone,
1,3-dimethyl-2-imidazole, imidazole,
N-methyl-2-pyrrolidone and the like, and further,
Saccharides can also be included, and examples of saccharides include monosaccharides, disaccharide oligosaccharides (including trisaccharides and tetrasaccharides) and polysaccharides, preferably glucose, mannose, fructose, ribose, xylose, arabinose. , Galactose, aldonic acid, glucitol (sorbitol), maltose, cellobiose, lactose, sucrose, trehalose, maltotriose and the like. Here, the polysaccharide means a sugar in a broad sense, and is used to include a substance widely existing in nature such as cellulose. The addition amount of these wetting agents is not particularly limited, but is suitably 0.5 to 40% by weight, preferably 2 to 20% by weight in the ink.

The magenta ink preferably contains a penetrant such as an alkyl ether derivative of a polyhydric alcohol. Specific examples of alkyl ether derivatives of polyhydric alcohols include diethylene glycol mono-n-
Butyl ether, triethylene glycol mono-n-butyl ether, and propylene glycol mono-n-
One or a mixture of two or more selected from butyl ether can be mentioned. Preference is given to using triethylene glycol mono-n-butyl ether and mixtures containing it. The addition amount of the alkyl ether derivative of the polyhydric alcohol is preferably about 0.5 to 20% by weight, more preferably 3 to 15% by weight, based on the dispersion to be produced.

The amount of the pigment and / or dye to be added to the magenta ink is appropriately determined within a range in which an image having a good hue can be realized in addition to the light resistance and water resistance of the pigment and / or dye. A range of about 10% by weight is preferred.

When a pigment is used as the colorant, the pigment is preferably added as a pigment dispersion obtained by dispersing the pigment in an aqueous medium with a dispersant or a surfactant. As the dispersant, any one which has already been generally used as a dispersant for dispersing a pigment can be used. For example, a polymer compound and a surfactant can be used, and more preferably a high-dispersion agent is used. It is a molecular compound. It is obvious to those skilled in the art that a polymer compound can be preferably used as a dispersant, but it is generally considered that dispersion is obtained when a repulsive force occurs that can repel the attractive force generated between pigment particles. . It is said that the repulsion is caused by a surface potential provided by an electric double layer generated on the surface of the particles, and by steric hindrance caused by an adsorption layer adsorbed on the surface of the particles and spreading from the surface. When these repulsions are greater (dense) and further away from the particle surface, a stable dispersion can be obtained. It is generally said that a more stable dispersion can be obtained with a polymer compound having a molecular weight ranging from thousands to tens of thousands than a surfactant having a molecular weight ranging from tens to hundreds.

Preferred examples of the polymer dispersant include natural polymers, and specific examples thereof include proteins such as glue, gelatin, casein and albumin, natural rubbers such as gum arabic and tragacanth, and savonin. Glucosides, alginic acid and propylene glycol alginate, alginic acid derivatives such as triethanolamine alginate, ammonium alginate and sodium alginate, and cellulose derivatives such as methylcellulose, carboxymethylcellulose, hydroxyethylcellulose and ethylhydroxyethylcellulose.

Preferred examples of the polymer dispersant include synthetic polymers, such as polyvinyl alcohols, polyvinylpyrrolidones, polyacrylic acid, acrylic acid-acrylonitrile copolymer, potassium acrylate-acrylonitrile copolymer, and vinyl acetate. Acrylic resins such as acrylic ester copolymers, acrylic acid-alkyl acrylate copolymers, styrene-acrylic acid copolymers, styrene-methacrylic acid-alkyl acrylate copolymers, styrene-α-methyl Styrene-acrylic resin such as styrene-acrylic acid copolymer, styrene-α-methylstyrene-acrylic acid-acrylic acid alkyl ester copolymer, styrene-maleic acid, styrene-maleic anhydride, vinylnaphthalene-acrylic acid copolymer Polymer, vinyl acetate And a vinyl acetate-fatty acid vinyl ethylene copolymer, a vinyl acetate maleate ester copolymer, and salts thereof.

Among these, a copolymer of a monomer having a hydrophobic group and a monomer having a hydrophilic group, and a polymer of a monomer having both a hydrophobic group and a hydrophilic group are particularly preferable. Examples of the above salts include diethylamine, ammonia, ethylamine, triethylamine, propylamine, isopropylamine, dipropylamine, butylamine, isobutylamine, triethanolamine,
Salts with diethanolamine, aminomethylpropanol morpholine and the like can be mentioned. These copolymers preferably have a weight-average molecular weight of about 3,000 to 30,000, more preferably about 5,000 to 15,000. The addition amount of these dispersants is not particularly limited, but is preferably 0.06 to 3 ratio, more preferably 0.125 to 3 ratio, based on Pigment 1.

Examples of preferred surfactants include:
Anionic surfactants (eg, sodium dodecylbenzenesulfonate, sodium laurate, ammonium salts of polyoxyethylene alkyl ether sulfate, etc.), nonionic surfactants (eg, polyoxyethylene alkyl ether, polyoxyethylene alkyl ester, Polyoxyethylene sorbitan fatty acid ester, polyoxyethylene alkylphenyl ether, polyoxyethylene alkylamine, polyoxyethylene alkylamide, etc.), and these can be used alone or in combination of two or more.

Further, it may contain acetylene glycol represented by the following formula (1).

[0045]

Embedded image

In the above formula (1), R ¹ , R ² , R
^3, and the alkyl group having 1 to 6 carbon atoms represented by R ⁴ is preferably an alkyl of 1 to 4 carbon atoms, more preferably a methyl group. Further, n and m are such that their sum is 0
It is an integer of up to 30. Preferred examples of the acetylene glycol compound represented by the formula (1) include 2,4,
7,9 tetramethyl-5-decyne-4,7-diol,
3,6-dimethyl-4-octyne-3,6-diol,
And 3,5-dimethyl-1-hexyn-3-ol. In addition, a commercially available product can be used as the compound of the formula (1). For example, Surfynol 104, 82, 465, 485 or TG manufactured by Nissin Chemical Co., Ltd. can be used. The amount of the acetylene glycol compound added is preferably about 0.01 to 10% by weight, more preferably 0.1 to 5% by weight, based on the dispersion to be produced.

Further, a pH adjuster can be added to the magenta ink for the purpose of further improving the dispersion stability of the colorant. It is preferable that the pH of the magenta ink is adjusted in the range of 5 to 12, and more preferably in the range of 6 to 10. Specific examples of the pH adjuster include sodium hydroxide, potassium hydroxide, lithium hydroxide, sodium carbonate, sodium hydrogen carbonate, potassium carbonate, lithium carbonate, sodium phosphate, potassium phosphate, lithium phosphate, and diphosphate. Potassium hydrogen, dipotassium hydrogen phosphate, sodium oxalate, potassium oxalate, lithium oxalate, sodium borate, sodium tetraborate, potassium metal such as potassium hydrogen phthalate, potassium hydrogen tartrate, ammonia, methylamine, ethylamine And amines such as diethylamine, tris (hydroxymethyl) aminomethane hydrochloride, triethanolamine, morpholine and propanolamine.

Further, the magenta ink may contain a viscosity modifier, an antioxidant, an ultraviolet absorber, an antiseptic / antifungal agent and the like.

The preparation of the magenta ink when a pigment is used as a colorant is preferably carried out by first preparing a pigment dispersion by dispersing the pigment in water to which the above-mentioned dispersant or surfactant is added, The pigment dispersion is mixed with an aqueous solution obtained by adding the various additives described above to water or water, if necessary, and the pigment is added to water, if necessary, May be mixed and dispersed in an aqueous solution obtained by adding the various additives described above.

When a dye is used as a coloring agent, the magenta ink is prepared in the same manner as when the pigment is used, when the dye is hardly soluble or insoluble in water, or when the dye is used. Instead of making a dispersion, this is done by dissolving the dye in an organic solvent. When the dye is water-soluble, the dye is mixed with water or an aqueous solution obtained by adding the above various additives as necessary.

[Light Magenta Ink] The term "light magenta ink" refers to a plurality of magenta inks having a low reflection density when recorded on a recording medium among a plurality of magenta inks in the same ink set. In this case, it means something other than the one having the highest reflection density. In the present embodiment, one or more pigments similar to the pigments that can be used in the above-described magenta ink are contained as the colorant. The content of the colorant in the light magenta ink is such that the reflection density on the recording medium when recording using the light magenta ink is 50% of the reflection density on the recording medium when recording using the dark magenta ink. The quantity is as follows: In addition, the light magenta ink may further contain, as a colorant, a dye that can be used in the magenta ink in addition to the pigment, and the weight ratio of the pigment to the dye is 100: 0 to 0.
1:99 is preferable, and 100: 0-1 is more preferable.
0:90. Also, it is preferable to contain at least water together with the pigment, to preferably contain an organic solvent, to be added as a pigment dispersion obtained by dispersing in an aqueous medium with a dispersant or a surfactant. It is the same as the case of the above-mentioned magenta ink that it is preferable that it contains a penetrant, that it contains a wetting agent, that it is preferable that a pH adjuster is added, and so on. The preparation of the light magenta ink is the same as the preparation method of the magenta ink when the pigment is used as a colorant.

[Other inks] Other inks use the following dyes as coloring agents. The content of the dye in the light-colored ink of other inks is such that the reflection density on the recording medium when recording using the light-colored ink is less than the reflection density on the recording medium when recording using the dark-colored ink. The amount is less than 50% of the concentration. In addition, other inks contain at least water with a dye, preferably contain an organic solvent, a dispersant, a surfactant, a penetrant, a wetting agent, a pH adjuster, and a preservative.
It is similar to the case of the above-mentioned magenta ink that a fungicide is preferably added. The preparation of the other inks is the same as the method of preparing the magenta ink when the dye is used as a colorant.

Dyes used in other inks include the following dyes. -As a dye used in the yellow ink, for example, CI
Direct Yellow 8, 9, 11, 12, 27, 28, 29, 33, 3
5, 39, 41, 44, 50, 53, 58, 59, 68, 86, 87, 93, 9
5, 96, 98, 100, 106, 108, 109, 110, 130, 132, 14
2, 144, 161, 163, but CI Direct Yellow 86 and / or 132 is preferably used. -As a dye used for cyan ink, for example, CI Direct Blue 1, 10, 15, 22, 25, 55, 67, 68, 71,
76, 77, 78, 80, 84, 86, 87, 90, 98, 106, 108, 10
9,151,156,158,159,160,168,189,192,193,19
4, 199, 200, 201, 202, 203, 207, 211, 213, 214, 21
8,225,229,236,237,244,248,249,251,252,26
4, 270, 280, 288, 289, 291,
Preferably, CI Direct Blue 199 is used. -As a dye used in black ink, for example, CI
Direct Black 9, 17, 19, 22, 32, 51, 56, 62, 6
9, 77, 80, 91, 94, 97, 108, 112, 113, 114, 117, 11
8, 121, 122, 125, 132, 146, 154, 166, 168, 173, 19
9 can be mentioned.

An embodiment of a recording method using a color ink set and a color ink cartridge according to the present invention will be described below in detail with reference to the drawings. FIG. 1 is a perspective view showing a color ink set and a color ink cartridge according to the present invention. FIG. 2 is a perspective view showing an assembled state of the color ink cartridge. FIG. 3 is a cross-sectional view taken along line AA in FIG. 2 showing the structure of the color ink cartridge. FIG. 4 is a cross-sectional view taken along a line BB in FIG. 2 showing the structure of the color ink cartridge. FIG. 5 is a perspective view illustrating a configuration of a carriage that holds the color ink cartridge according to the present invention. FIG.
1 is a schematic configuration diagram of an ink jet printer that performs a recording method according to the present invention.

An ink jet printer to which the color ink cartridge is applied will be described with reference to FIG. As shown in FIG. 6, the printer 20 includes a mechanism for transporting a sheet P by a paper feed remotor 22, a mechanism for reciprocating a carriage 30 by a carriage motor 24 while opposing a platen 26, and a mechanism mounted on the carriage 30. And a control circuit 40 that controls the ejection of ink and the formation of dots by driving the print head 28, and the control circuit 40 that controls the exchange of signals with the paper feed motor 22, the carriage motor 24, the print head 28, and the operation panel 32. It is composed of

The mechanism for conveying the sheet P as a recording medium is as follows.
A gear train for transmitting the rotation of the paper feed remotor 22 not only to the platen 26 but also to a paper transport roller (not shown) is provided.
The mechanism for reciprocating the carriage 30 includes a platen 26
A slide shaft 34 erected in parallel with the axis of the carriage 30 and slidably holds the carriage 30, a pulley 38 for extending an endless drive belt 36 between the carriage motor 24, and an origin position of the carriage 30. It comprises a position detection sensor 39 and the like for detecting.

Although the control system is not shown,
The control circuit provided in the printer is, for example, a well-known CP.
Character generator (CG) storing U, P-ROM and RAM storing programs, dot matrix of characters
It is configured as an arithmetic and logic operation circuit centered on the above, etc. In addition, an I / F dedicated circuit dedicated to interfacing with an external motor or the like, and connected to this I / F dedicated circuit to drive the print head 28 A head drive circuit for driving the paper feed remotor 22 and the carriage motor 24 is also provided.

Next, the configuration of the color ink cartridge 70 and the carriage 30 to which the color ink cartridge 70 is mounted will be described. As shown in FIG.
Has a configuration in which a cartridge 78 for black ink and a cartridge 70 for color ink (see FIG. 2) can be mounted, and includes, for example, a partition plate 31 for partitioning both cartridges so that they can be mounted. A total of six ink discharge heads are formed on the print head 28 below the carriage 30, and
At the bottom of 30, introduction pipes 71 to 76 are provided to guide the ink from the ink tank to the head for each color. When the black ink cartridge and the color ink cartridge 70 are mounted on the carriage 30 from above, the introduction tubes 71 to 76 are pushed into the connection holes provided in each cartridge.

The internal structure of the color ink cartridge 70 will be described with reference to FIG. The color ink cartridge 70 contains two types of inks of magenta and cyan, and five types of inks as a whole. The ink cartridge 70 is made of, for example, polypropylene or the like, and is formed in a rectangular parallelepiped shape as a whole so as to be able to store as much ink as possible in a limited volume without a protruding portion on the surface. Inside,
Ink storage chambers 102b to 102e storing two types of magenta and cyan inks, and an ink storage chamber 102a storing yellow ink wider than these,
Are formed through the partition.

In the color ink cartridge 70, the outer wall 104 is formed to be thicker than the partition wall 103, and the opening edge 105 at the upper end is formed so as to bulge outward from the side wall. Due to the opening edge 105, the color ink cartridge 70 has sufficient rigidity. At the corners of the outer wall 104, ribs 106 that serve both for positioning with respect to the carriage 30 and for maintaining its own shape are integrally formed so as to protrude.

The bottom surfaces 108 of the ink storage chambers 102a to 102e have cylindrical ink supply ports 110a to 110e connected to each other.
Are formed to protrude. The shapes of the ink supply ports 110a to 110e are shown in detail in FIGS. These ink supply ports 110a to 110e are
The outer periphery is surrounded by a strip-shaped common frame 112, and each is further connected to the frame 112 by a rib 111.

Both ends of the frame 112 are formed inside the outer wall 104 and protrude from the ink supply ports 110a and 110e at both ends. Accordingly, the end face of the frame 112 has a sufficient area. For example, the sealing tape 115 that seals the ink supply ports 110a to 110e during storage does not have both ends protruding from the outer wall 104, and All the ink supply ports 110a to 110e can be attached so as to be simultaneously sealed. When applying tape 115, keep the air inside
After once flowing into the air escape part formed inside 12
It is structured so that it can escape from the notch provided in the upper green of 112. Therefore, the tape 115 can adhere to the end surface of the frame 112 without any problems.

Further, these ink supply ports 110a to 110e are:
As shown in FIG. 3, the ink supply port 110a is formed to project from the bottom surface 108 at a constant interval, and the ink supply port 110a corresponding to the wide yellow ink storage chamber 102a is connected to the ink storage chamber 10a.
When viewed from 2a, it will be biased inward,
The introduction pipes 72 to 76 on the print head 28 side protruding from the carriage 30 can be provided at equal intervals in accordance with the intervals between the ink supply ports 110a to 110e.

Each of the ink supply ports 110a to 110e has a seal rubber 1
When the color ink cartridge 70 is mounted on the carriage 30, the introduction pipes 72 to 76 and the ink supply ports 110a to 110e are connected without any gap.

On the other hand, on the bottom surface 108 of the color ink cartridge 70, engagement recesses 117 are formed along the rows of the ink supply ports 110a to 110e. By engaging the engagement recess 117 with the support frame 101 of the lifter provided on the carriage 30, erroneous mounting on the color ink cartridge 70 can be prevented. Further, by providing the engagement recess 117, a step 118 is formed inside the color ink cartridge 70, and the following operation and effect are obtained. That is, the ink existing inside the color ink cartridge 70 and at a portion lower than the discharge port through which the ink exits is the form 11
Even if the capillary action by 9 is used, it cannot be completely discharged. Therefore, by forming the step portion 118, it is assumed that the foam 119 inside the color ink cartridge 70 that absorbs ink cannot exist in this portion, and the amount of waste ink that is not used is reduced. Further, when the entire color ink cartridge 70 is placed in an aluminum pack and packed under reduced pressure, a space for reduced pressure is required, and thus the step 118 secures this space.

At the top of the color ink cartridge 70,
Lid 12 that seals the opening of color ink cartridge 70
0 is fittable. As shown in FIGS. 1 to 4, two rows of vertical ribs 121 for pressing the foam 119 stored in the ink storage chambers 102 a to 102 e are provided on the inner surface of the lid 120 for each of the ink storage chambers 102 a to 102 e. The cover 120 is formed to have a predetermined interval and to have such a length that the cover 120 can be slightly slid in the longitudinal direction. These vertical ribs
In the portion 121, a portion near the ink supply port 110 is formed higher than other portions. Therefore, when the lid 120 is fitted into the main body of the color ink cartridge 70, the vertical rib 121
The foam 119 on the side of the ink supply port is compressed more strongly than the other parts, and the pores of the form 119 on the side of the ink supply port are reduced. As a result, on the ink supply port side, the capillary action is stronger than in the other portions, and the ink uniformly absorbed in the foam 119 is reduced with the decrease of the ink.
Can be collected near 110.

The arrangement of six rows of color heads in the print head is, for example, divided into three sets with two heads as one set at appropriate intervals. A black ink head is disposed at an end close to a black ink cartridge (not shown), and next to it is a cyan (C1 in FIG. 2) ink head. Adjacent to this set are a head for light cyan ink (C2 in FIG. 2) and a head for magenta (M1 in FIG. 2) having a lower density than the cyan ink supplied to the cyan ink head. . Further, in the next set, a head for light magenta ink (M2 in FIG. 2) having a lower density than the normal magenta ink (C1) and a head for yellow (Y in FIG. 2) are arranged. .

The colorant in the color ink set and the color ink cartridge of the present embodiment is such that the light magenta ink (M2) contains a pigment, and the other inks (C
1, C2, M1, Y) are dyes. By using a colorant in such a combination as an ink, not only good image quality such as color reproducibility can be maintained, but also excellent abrasion resistance and discoloration / fading deterioration can be effectively prevented.

Further, as in the present embodiment, a plurality of inks composed of a dye colorant and a light magenta ink composed of a pigment colorant are integrated, so that good image quality can be formed.
The effect of improving the abrasion resistance and the effect of preventing discoloration / fading deterioration can be reliably achieved, and the cartridge can be easily mounted on the carriage.

[0070]

Next, the present invention will be described in detail with reference to examples of the present invention, but the present invention is not limited to these examples. In the following description, the following abbreviations are used. TEGmBE: triethylene glycol mono-n-butyl ether DEGmBE: diethylene glycol mono-n-butyl ether TEA: triethanolamine NaOH: sodium hydroxide KOH: potassium hydroxide

Example 1 A light magenta ink is the following light magenta ink, and the other inks are the following five colors of dark magenta ink, yellow ink, dark cyan ink, and light cyan ink for inkjet recording. Ink set. [Light Magenta Ink] CI Pigment Red 122 1.5% by weight Styrene-acrylic acid copolymer (dispersant) Molecular weight = 7000 4% by weight Diethylene glycol 5% by weight Glycerin 10% by weight TEGmBE 8% by weight Surfynol 465 1% by weight potassium hydroxide 0.2% by weight pure water balance The above components were combined with a minimill 100 (Eiger Machinery Inc.,
Bensenbille IL) and milled at 3000 rpm for 2 hours. The obtained dispersion was filtered through a 5 μm membrane filter to obtain an ink composition containing 1.5% by weight of a pigment. [Each Ink] The following coloring agents were used in place of the coloring agents in the light magenta ink. Note that no dispersant is added to each ink.・ Magenta ink: CI Direct Red 227 4% by weight ・ Yellow ink: CI Direct Yellow 86 3.5% by weight ・ Dark cyan ink: CI Direct Blue 199 3.5% by weight ・ Light cyan ink: CI Direct Blue 199 1% by weight

Example 2 The light magenta ink is the light magenta ink described above, and the other inks are the following five colors of dark magenta ink, yellow ink, dark cyan ink, and light cyan ink for inkjet recording. Ink set. [Each Ink] The following coloring agents were used in place of the coloring agents in the light magenta ink. No dispersant is added to the ink other than the dark magenta ink.・ Dark magenta ink: CI Pigment Red 122 4% by weight ・ Yellow ink: CI Direct Yellow 132 3.5% by weight ・ Dark cyan ink: CI Direct Blue 199 3.5% by weight ・ Light cyan ink: CI Direct Blue 199 1% by weight

Embodiment 3 The light magenta ink is the light magenta ink described above, and the other inks are the following five colors of dark magenta ink, yellow ink, dark cyan ink, and light cyan ink for inkjet recording. Ink set. [Each Ink] The following coloring agents were used in place of the coloring agents in the light magenta ink. No dispersant is added to each ink.・ Dark magenta ink: CI Direct Red 227 4% by weight ・ Yellow ink: CI Direct Yellow 132 2% by weight CI Direct Yellow 86 2% by weight ・ Dark cyan ink: CI Direct Blue 199 3.5% by weight ・ Light cyan ink: CI Direct Blue 199 1% by weight

Example 4 Dark Magenta Ink: CI Pigment Red 122 3.2% by weight CI Direct Red 227 0.8% by weight The light color of Example 1 was used except that the above composition (pigment: dye = 8: 2) was used. A dark magenta ink was prepared by using the same composition as the magenta ink, and a color ink set for inkjet recording was prepared by using the same other inks as in Example 1.

Example 5 Dark Magenta Ink: CI Pigment Red 122 2% by weight CI Direct Red 227 2% by weight The light color of Example 1 was used except that the above composition (pigment: dye = 5: 5) was used. A dark magenta ink was prepared by using the same composition as the magenta ink, and a color ink set for inkjet recording was prepared by using the same other inks as in Example 1.

Example 6 Dark Magenta Ink: CI Pigment Red 122 0.8% by weight CI Direct Red 227 3.2% by weight The light color of Example 1 was used except that the above composition (pigment: dye = 2: 8) was used. A dark magenta ink was prepared by using the same composition as the magenta ink, and a color ink set for inkjet recording was prepared by using the same other inks as in Example 1.

Comparative Example 1 An ink jet recording color ink set was the same as in Example 1 except that the colorant used for the light magenta ink was CI Direct Red 227 (1% by weight). In addition,
No dispersant is added to the light magenta ink.

The above Examples and Comparative Examples were evaluated by the following methods, and the results are shown in Table 1. ◇ Test method (1) Image quality Refill the inks prepared in the examples and comparative examples with color ink cartridges (PMICIC) of the inkjet printer PM700C (manufactured by Seiko Epson Corporation), and use genuine MJIC7 black ink cartridges on PPC paper. And PM700C for inkjet glossy paper (Seiko Epson Corporation, Super Fine glossy paper (MJA4SP3))
And high-definition color digital standard image data (ISO / JIS-SCI
The image name portrait (sample number 1, image identification symbol N1) of D) was printed, and the sharpness of the image was visually observed. Visually evaluate image sharpness Vividly reproduced image: A Image is unclear: B (2) Light fastness test-1 Using the image obtained in (1) above, xenon fade An acceleration test at 36 kJ / m ² was performed using a meter (C135A). Further, the same accelerated test was performed by printing a blue color. Background of the portrait image before and after the test (gray color)
And blue color difference ΔE were measured by a method specified in JIS-Z8730. Judgment Criteria Color difference is less than 5: A Color difference is 5 to 10: B Color difference is more than 10: C (3) Light fastness test-2 The inks prepared in Examples and Comparative Examples are inkjet printer PM700C (manufactured by Seiko Epson Corporation). Color ink cartridge (PMICIC), black ink cartridge uses genuine MJIC7, and image density (OD value) on PPC paper and glossy paper exclusively for inkjet (Seiko Epson Corporation, glossy paper for super fine (MJA4SP3)) ) Is about 1.0, the color is printed with yellow, magenta, and cyan inks, and the OD value before and after the test is measured using a spectrophotometer Gretag SPM100-II (Gretag) in the same manner as in the light resistance test-1. Measurement was performed to determine the density reduction rate of each color print. Judgment criteria Concentration residual ratio 90% or more: A concentration residual ratio 80-90% or more: B Concentration residual ratio less than 80%: C

[0079]

[Table 1]

[0080]

As described in detail above, by using the color ink set (color ink cartridge) of the present invention, that is, when performing color printing using a plurality of magenta inks and other inks, At least the light magenta ink among the multiple magenta inks uses a pigment that contains a pigment as a colorant, and by using a dye as a colorant for other inks, without causing clogging, color reproducibility, etc. Can maintain good image quality, impart rub resistance to images, improve the color fade of magenta, and improve the color balance of gray including magenta, and the light resistance of blue represented by the combination of magenta and cyan Discoloration due to harmful radicals or active oxygen generated by light,
Discoloration was prevented.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of an ink set and an ink cartridge according to the present invention.

FIG. 2 is a perspective view showing an assembled state of the ink cartridge shown in FIG.

FIG. 3 is a cross-sectional view taken along a line AA in FIG. 2 showing the structure of the ink cartridge.

FIG. 4 is a sectional view taken along line BB in FIG. 2 showing the structure of the ink cartridge.

FIG. 5 is a perspective view illustrating a configuration of a carriage that holds the ink cartridge according to the present invention.

FIG. 6 is a schematic configuration diagram of an ink jet printer that performs a recording method according to the present invention.

[Explanation of symbols]

 20 Inkjet printer 70 Ink cartridge 102 Ink storage chamber 103 Partition wall 104 Outer side wall 105 Opening edge 106 Rib 110 Ink supply port 119 Form 120 Lid 121 Vertical rib

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Yukari Sano 3-3-5 Yamato, Suwa City, Nagano Prefecture Inside Seiko Epson Corporation (72) Inventor Akio Owato 3-3-5 Yamato Suwa City, Nagano Prefecture Seiko Epson Inside the corporation

Claims (13)

[Claims] In a color ink set having a plurality of magenta inks having different reflection densities when recorded on a recording medium, at least a light magenta ink among the plurality of magenta inks contains a pigment as a colorant, and the other inks An ink set, wherein the colorant is a dye. 2. The light magenta ink as a colorant,
2. The ink set according to claim 1, comprising CI Pigment Red 122. 3. The light magenta ink as a colorant,
CI Pigment Red 122, and the colorant of the yellow ink is CI Direct Yellow 132 and / or CI Direct Yellow 132.
Direct Yellow 86, the colorant of cyan ink is C.
2. The ink set according to claim 1, wherein the ink set is I. Direct Blue 199. 4. The ink set according to claim 3, wherein the cyan ink comprises two cyan inks of different shades. 5. The magenta ink comprises two shades of magenta ink, and the two shades of magenta ink contain a pigment as a colorant.
The ink set according to any one of the above. 6. The ink set according to claim 1, wherein the colorant of the magenta ink is mixed with a pigment. 7. A color ink cartridge containing a plurality of magenta inks and another ink integrally or at least partly independently, wherein at least a light magenta ink among the plurality of magenta inks is a pigment as a colorant. And a colorant of the other ink is a dye. 8. The light magenta ink as a colorant,
The ink cartridge according to claim 7, comprising CI Pigment Red 122. 9. The light magenta ink as a colorant,
CI Pigment Red 122, and the colorant of the yellow ink is CI Direct Yellow 132 and / or CI Direct Yellow 132.
Direct Yellow 86, the colorant of cyan ink is C.
The ink cartridge according to claim 7, wherein the ink cartridge is I. Direct Blue 199. 10. The magenta ink comprises two shades of magenta ink, and the two shades of magenta ink contain a pigment as a colorant.
10. The ink cartridge according to any one of 9. 11. The ink cartridge according to claim 7, wherein a colorant of the magenta ink is mixed with a pigment. 12. When performing color printing using a plurality of magenta inks and another ink, at least the light magenta ink of the plurality of magenta inks contains a pigment as a colorant, and the colorant of another ink is used. Using a color ink set wherein is a dye. 13. A recorded matter on which color printing has been performed using a plurality of magenta inks and another ink, wherein at least the light magenta ink among the plurality of magenta inks contains a pigment as a colorant, A recorded matter characterized by being recorded using a color ink set in which a colorant of an ink is a dye.