JP2003105240A - Ink, recording method using the same and ink-jet recording method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink excellent in ink stability, smear resistance, ink preservation property and stability after printing (scratch resistance), a recording method and an ink-jet recording method using the ink. SOLUTION: In the ink containing at least a photopolymerizable compound, a photopolymerization initiator and a coloring agent, it is characterized in that its viscosity is 500-50,000 mPa.s at 25 deg.C and 3-30 mPa.s at 80 deg.C and a surface tension is 20-60 mN/m.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink suitable for recording on any medium including a medium that does not absorb ink, a recording method using this ink, and an inkjet recording method.

[0002]

2. Description of the Related Art Conventionally, a water-soluble liquid ink composition has been widely used as an ink composition for ink jet recording (hereinafter, also simply referred to as an ink). In addition, a hot-melt ink composition that is made of a wax that is solid at room temperature is used to liquefy by heating, etc., to be jetted by applying some energy, and to cool and solidify while adhering to the recording medium to form recording dots. A hot-melt type ink jet recording method has been proposed. Since this ink is solid at room temperature, it does not become dirty during handling, and since the amount of evaporation of the ink at the time of melting can be minimized, the nozzle is not clogged. Furthermore, since it solidifies immediately after it adheres, there is no "bleeding", and from Japanese paper to drawing paper, postcards,
There is an advantage that various recording media such as plastic sheets can be used without pretreatment. U.S. Pat. Nos. 4,391,369 and 4,484,948 disclose ink compositions that provide good print quality regardless of paper quality.

Further, Japanese Patent Application Laid-Open No. 56-93776 discloses an ultraviolet curable resin type ink composition having good adhesion to a metal surface, and further ink jet recording which is cured by exposure to ultraviolet rays. As an ink for use, as disclosed in U.S. Pat. No. 4,228,438, an epoxy-modified acrylic resin and a urethane-modified acrylic resin are used as binders, and the ink is 5 μm.
An ink containing a pigment having the following particle diameter as a coloring component, or an ink using as a binder a cationically polymerizable epoxy resin disclosed in JP-A-58-32674.
As described in JP-A-5-186725,
There are some which use water-soluble or non-water-soluble dyes, and those which facilitate printing on plain paper and recycled paper are disclosed.

When the above-mentioned water-based ink is used for printing, it becomes difficult to print on a recording medium having no ink absorbability, and a large-sized ink drying device is required even when using special paper. ing. Further, due to the problem of bleeding, high-definition printing is difficult and the resolution is limited, so that there are problems such as limited applications.

The hot-melt type ink using wax is capable of high-speed printing, but has very low abrasion resistance, and it is difficult to obtain reliability after printing. Further, the method of simply curing the recording liquid with light such as ultraviolet rays has an insufficient curing speed, and high-definition printing is difficult due to the problem of bleeding, and the resolution is limited.

On the other hand, when an organic pigment is used as a colorant in an ink composition for ink jet, it has a drawback that it is easy to separate in the molten state. As is well known, the settling of particles dispersed in a medium changes depending on the particle size of the particles, the viscosity of the dispersing medium and the settling time, and the viscosity of the dispersing medium is less likely to settle as the viscosity becomes higher. On the other hand, when printing with an inkjet printer, the lower viscosity of the ink used is advantageous for high speed and high density and is suitable for high reliability printing, and both have conflicting characteristics. It was

The ink jet recording method using an organic pigment as a colorant has many advantages over the ink jet recording method using a dye, particularly in terms of light resistance.
Equipment, general household printers, facsimiles, office printers, indoor / outdoor posters, large signboards,
It is expected to be applied to cars, glass, elevators, decoration of walls and buildings, and even printing on cloth, and there is a demand for urgent solution of the above-mentioned problems.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and its objects are character quality, bleeding resistance, ink storability, and stability after printing (rubbing resistance, etc.).
An object of the present invention is to provide an ink which is excellent in printing quality and can stably print a high-definition image on any recording medium, and a recording method and an inkjet recording method using the ink.

[0009]

The above objects of the present invention have been achieved by the following constitutions.

1. In an ink containing at least a photopolymerizable compound, a photopolymerization initiator and a colorant, the viscosity of the ink is 500 to 50,000 mPa · s at 25 ° C.
An ink having a surface tension of 3 to 30 mPa · s at 0 ° C. and a surface tension of 20 to 60 mN / m.

2. The colorant is a pigment, and the addition amount of the pigment is 0.5 to 30% by mass.
Ink according to item.

3. 2. The pigment is a dispersion, and the average dispersed particle diameter is 200 nm or less.
Ink according to item.

4. The ink according to any one of items 1 to 3, wherein two or more photopolymerizable compounds are used in combination.

5. 5. The ratio of the photopolymerizable compound having one polymerization reactive group is 0 to 50% by mass with respect to the photopolymerizable compound having two or more polymerization reactive groups. ink.

6. The ink according to any one of items 1 to 5, wherein the pH of the ink is 4 to 10.

7. 1 to 6 containing a vehicle, wherein the content of the vehicle is 1 to 50% by mass.
The ink according to any one of items.

8. The ink according to any one of the items 1 to 7 is heated to 60 to 180 ° C., and ink droplets are ejected by applying ejection energy to the ink to record at 15 to 40 ° C. After fixing the image on the medium,
A recording method characterized by applying actinic rays.

9. 9. The recording method according to item 8, wherein the actinic ray is ultraviolet light.

10. An ink jet recording method using the ink according to any one of items 1 to 7 above, wherein ink droplets formed by an ink jet method are attached to a recording medium to perform recording.

11. Item 11. The inkjet recording method described in Item 10, wherein the inkjet method is a method that utilizes a piezoelectric action of a piezoelectric material.

12. 12. The inkjet recording method as described in 10 or 11 above, wherein the recording medium is non-ink absorbing.

13. 13. The inkjet recording method according to any one of the items 10 to 12, further comprising a step of applying ultraviolet rays to the ink attached to the recording medium.

As a result of earnest studies on the above problems, the present inventor has found that the viscosity of an ink containing at least a photopolymerizable compound, a photopolymerization initiator and a colorant is
500 to 50,000 mPa · s at 25 ° C, 3 to 80 ° C
30 mPa · s and the surface tension of the ink is 20 to 6
It has been found that by setting it to 0 mN / m, high-speed printing can be performed similarly to the hot-melt type ink using wax, and the rubbing property which is a problem with the hot-melt can be largely solved. Further, in the method of simply curing the ink liquid with ultraviolet rays, it was difficult to suppress the bleeding. However, with the configuration of the present invention, the bleeding, particularly the bleeding on the non-ink-absorbent recording medium, is significantly increased. It has been found that the present invention can be improved and the present invention has been completed.

The details of the present invention will be described below. In the invention according to claim 1, in an ink containing a photopolymerizable compound, a photopolymerization initiator, and a coloring agent, the viscosity of the ink is 500 to 50,000 mPa · s at 25 ° C, and 80 ° C.
Is 3 to 30 mPa · s, and the surface tension of the ink is 20 to 60 mN / m.

The ink of the present invention has a viscosity at 25 ° C. of 50.
It is a viscous liquid of 0 to 50,000 mPa · s and a liquid of 3 to 30 mPa · s at 80 ° C. More preferably, the viscosity at 25 ° C is 500 to 10,000 mPa · s.
And more preferably 1000 to 10000 mPa.
・ S. If it is less than 500 mPa · s, blurring is deteriorated, and if it exceeds 50,000 mPa · s, smoothness of image quality is lost. The viscosity at 80 ° C. is preferably 3 to 30 mPa · s, more preferably 3 to 20 mPa · s. If it is less than 3 mPa · s, problems occur in high-speed injection,
Further, if it exceeds 30 mPa · s, the injection property deteriorates.

There are no particular restrictions on the method for obtaining the viscosity at each temperature specified in the present invention. For example, the concentration of each additive (photopolymerizable compound, photopolymerization initiator, colorant, etc.) and the amount of solvent. By adjusting the viscosity modifier, etc.,
It can have desired viscosity characteristics.

The viscosity (liquid viscosity) referred to in the present invention is JI
There is no particular limitation as long as it is a standard solution for viscometer calibration specified in SZ8809, and a rotary, vibrating or capillary viscometer can be used. As the viscometer, a Saybolt viscometer, a Redwood viscometer, or the like can be used. For example, a conical plate type E manufactured by Tokimec Co., Ltd.
Type viscometer, E Type Viscom manufactured by Toki Sangyo Co., Ltd.
eter (rotational viscometer), B type viscometer B manufactured by Tokyo Keiki Co., Ltd.
L, FVM-80A made by Yamaichi Denki Co., Nametore
Industrial Viscoliner, Yamaichi Denki VI
SCO MATE MODEL VM-1A etc. can be mentioned.

The ink of the present invention is characterized in that the surface tension is in the range of 20 to 60 mN / m, preferably 25 to 50 mN, in consideration of the wettability of the ink to the recording medium and the head nozzle member. The range is / m. When the surface tension of the ink is lower than 20 mN / m, the ink easily overflows from the nozzle, and 6
When it is higher than 0 mN / m, the drying time becomes long.

In order to adjust the surface tension, a surfactant may be contained if necessary. As the surfactant preferably used in the ink of the present invention, for example, anionic surfactants such as dialkylsulfosuccinates, alkylnaphthalenesulfonates and fatty acid salts, polyoxyethylene alkyl ethers, polyoxyethylene alkyl allyls. Examples thereof include nonionic surfactants such as ethers, acetylene glycols, polyoxyethylene / polyoxypropylene block copolymers, and cationic surfactants such as alkylamine salts and quaternary ammonium salts. Of these, anionic surfactants and nonionic surfactants are particularly preferable.

The invention according to claim 6 is characterized in that the pH of the ink is from 4 to 10, and more preferably from 5 to 9. Although the reason for the effect of the present invention is not clear, it is considered that the compatibility between the pigment and the photopolymerizable compound contributes to the dispersion stability of the pigment.

The ink of the present invention contains a photopolymerizable compound and a photopolymerization initiator. The photopolymerizable compound is a radically polymerizable compound, and is, for example, JP-A-7-159.
983, Japanese Patent Publication No. 7-31399, Japanese Patent Laid-Open No. 8-224.
982, 10-863, etc. and Japanese Patent Application No. 7-
Photocurable materials using the photopolymerizable composition described in Japanese Patent No. 231444 and cationically curable photocurable resins are known, and recently, they have been sensitized to a long wavelength region of visible light or longer. The photo-curable resin of the photo-cationic polymerization system, for example,
It is disclosed in JP-A-6-43633, JP-A-8-324137, and the like.

The radically polymerizable compound is a compound having a radically polymerizable ethylenically unsaturated bond, and may be any compound as long as it has at least one radically polymerizable ethylenically unsaturated bond in the molecule. Often,
Those having chemical forms such as monomers, oligomers and polymers are included. The radical-polymerizable compound may be used alone, or two or more kinds thereof may be used in combination at an arbitrary ratio in order to improve target properties.

Examples of the radically polymerizable compound having an ethylenically unsaturated bond include unsaturated carboxylic acids such as acrylic acid, methacrylic acid, itaconic acid, crotonic acid, isocrotonic acid and maleic acid, and salts and esters thereof.
Radical polymerizable compounds such as urethane, amide and anhydride, acrylonitrile, styrene, and various unsaturated polyesters, unsaturated polyethers, unsaturated polyamides and unsaturated urethanes can be mentioned. Specifically, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, butoxyethyl acrylate, carbitol acrylate, cyclohexyl acrylate, tetrahydrofurfuryl acrylate, benzyl acrylate, bis (4-acryloxypolyethoxyphenyl) propane,
Neopentyl glycol diacrylate, 1,6-hexanediol diacrylate, ethylene glycol diacrylate, diethylene glycol diacrylate, triethylene glycol diacrylate, tetraethylene glycol diacrylate, polyethylene glycol diacrylate, polypropylene glycol diacrylate, pentaerythritol triacrylate. , Pentaerythritol tetraacrylate, dipentaerythritol tetraacrylate, trimethylolpropane triacrylate, tetramethylolmethane tetraacrylate, oligoester acrylate, acrylic acid derivatives such as N-methylol acrylamide, diacetone acrylamide, epoxy acrylate, methyl methacrylate, n- Butylme Acrylate, 2-ethylhexyl methacrylate, lauryl methacrylate, allyl methacrylate, glycidyl methacrylate, benzyl methacrylate, dimethylaminomethyl methacrylate, 1,
6-hexanediol dimethacrylate, ethylene glycol dimethacrylate, triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, polypropylene glycol dimethacrylate, trimethylolethane trimethacrylate, trimethylolpropane trimethacrylate, 2,2-bis (4-methacryloxy) Methacryl derivatives such as polyethoxyphenyl) propane, other, allyl glycidyl ether, diallyl phthalate, derivatives of allyl compounds such as triallyl trimellitate, more specifically, Shinzo Yamashita, "Crosslinking agent handbook", (1981 Taiseisha); Kiyomi Kato, "UV / EB curing handbook (raw materials)" (1985, Kobunshi Kogyokai); Radtech Research Group, "UV / EB" Application of technology and the market ", 79
Page, (1989, CMC); Eiichiro Takiyama,
Commercially available products described in "Polyester Resin Handbook" (1988, Nikkan Kogyo Shimbun) and the like, or radically polymerizable or crosslinkable monomers, oligomers and polymers known in the art can be used. The amount of the radically polymerizable compound added is preferably 1 to 97% by mass, more preferably 30 to 95% by mass.

As a radical polymerization initiator, Japanese Examined Patent Publication No. S59
-1281, Japanese Patent Publication No. 61-9621, and JP-A-6-6
Triazine derivatives described in each publication such as 0-60104,
JP-A-59-1504 and JP-A-61-243807
Organic peroxides described in each publication such as Japanese Patent Publication No. 43-23
684, Japanese Patent Publication No. 44-6413, Japanese Patent Publication No. 44-64
No. 13 and Japanese Patent Publication No. 47-1604, and diazonium compounds described in US Pat. No. 3,567,453, US Pat. Nos. 2,848,328, 2,852,379, and No. 2,940,853, organic azide compounds described in each specification, JP-B-36-2206
No. 2, JP-B-37-13109, JP-B-38-180
No. 15, Japanese Patent Publication No. 45-9610 and other ortho-quinone diazides, Japanese Patent Publication No. 55-39162,
JP-A-59-14023 and the like, and "Macromolecules, No. 10"
Vol. 1, p. 1307 (1977), various onium compounds, azo compounds described in JP-A-59-142205, JP-A-1-54440, EP 109,851, and EP 126. , 712
No. etc., each statement, "Journal of Imaging
Science "(J.Imag.Sci.)", No. 30
Vol., Page 174 (1986), metal allene complexes, Japanese Patent Application No. 4-56831 and Japanese Patent Application No. 4-89.
(Oxo) sulfonium organoboron complex described in Japanese Patent No. 535, Titanocenes described in JP-A No. 61-151197, “Coordination Chemistry Review”.
y Review) ", Vol. 84, pages 85-277 (1988) and transition metal complexes containing a transition metal such as ruthenium described in JP-A-2-182701.
2,4,5-triarylimidazole dimers and carbon tetrabromide described in JP-A-3-209477 and JP-A-5-
Examples thereof include organic halogen compounds described in JP-A 9-107344. These polymerization initiators are preferably contained in the range of 0.01 to 10 parts by mass with respect to 100 parts by mass of the compound having a radically polymerizable ethylenic unsaturated bond.

As the cationic polymerization type photocurable resin, an epoxy type ultraviolet curable prepolymer of a type (mainly an epoxy type) in which polymerization is caused by cationic polymerization, and a monomer has two or more epoxy groups in one molecule. The prepolymer contained can be mentioned. Examples of such prepolymers include alicyclic polyepoxides, polyglycidyl esters of polybasic acids, polyglycidyl ethers of polyhydric alcohols, polyglycidyl ethers of polyoxyalkylene glycols, and polyglycidyl aromatic polyols. Examples thereof include ethers, hydrogenated compounds of polyglycidyl ethers of aromatic polyols, urethane polyepoxy compounds and epoxidized polybutadienes. These prepolymers can be used alone, or in addition,
It is also possible to use a mixture of two or more thereof.

Other cationically polymerizable compounds contained in the cationically polymerizable composition include, for example, the following (1) styrene derivatives, (2) vinylnaphthalene derivatives, and (3).
Examples thereof include vinyl ethers and (4) N-vinyl compounds.

(1) Styrene derivative For example, styrene, p-methylstyrene, p-methoxystyrene, β-methylstyrene, p-methyl-β-methylstyrene, α-methylstyrene, p-methoxy-β-
Methylstyrene etc. (2) Vinylnaphthalene derivative, for example, 1-vinylnaphthalene, α-methyl-1-vinylnaphthalene, β-methyl-1-vinylnaphthalene, 4
-Methyl-1-vinylnaphthalene, 4-methoxy-1-
(3) Vinyl ethers such as vinyl naphthalene, for example, isobutyl vinyl ether, ethyl vinyl ether, phenyl vinyl ether, p-methylphenyl vinyl ether, p-methoxyphenyl vinyl ether,
α-Methylphenyl vinyl ether, β-methyl isobutyl vinyl ether, β-chloroisobutyl vinyl ether, etc. (4) N-vinyl compounds such as N-vinylcarbazole, N-vinylpyrrolidone, N-vinylindole, N-vinylpyrrole, N-
Vinylphenothiazine, N-vinylacetanilide, N
-Vinylethylacetamide, N-vinylsuccinimide, N-vinylphthalimide, N-vinylcaprolactam, N-vinylimidazole and the like.

The content of the above cationically polymerizable compound in the cationically polymerizable composition is preferably 1 to 97% by mass, more preferably 30 to 95% by mass.

Aromatic onium salts can be mentioned as the initiator of the cationic polymerization type photocurable resin. As the aromatic onium salt, a salt of a Group Va element of the periodic table, for example, a phosphonium salt (for example, triphenylphenacylphosphonium hexafluorophosphate), a salt of a Group VIa element, for example, a sulfonium salt (for example, triphenylsulfonium tetrafluoroborate) , Triphenylsulfonium hexafluorophosphate, tris (4-thiomethoxyphenyl) hexafluorophosphate, sulfonium and triphenylsulfonium hexisafluoroantimonate), and salts of Group VIIa elements, such as iodonium salts (eg, diphenyliodonium chloride). Etc.) can be mentioned.

The use of such an aromatic onium salt as a cationic polymerization initiator in the polymerization of an epoxy compound is disclosed in US Pat. Nos. 4,058,401 and 4,0.
69,055, 4,101,513 and 4,161,478.

The preferred cationic polymerization initiator is
Examples thereof include sulfonium salts of Group VIa elements. Among them, from the viewpoint of ultraviolet curability and storage stability of the ultraviolet curable composition, triarylsulfonium hexafluoroantimonate is preferable. Also, Photo Polymer Handbook (Photo Polymer Conversation Edition, Industrial Research Committee issue 1
989), pages 39 to 56, known photopolymerization initiators, and compounds described in JP-A-64-13142 and JP-A-2-4804 can be optionally used.

The invention according to claim 4 is characterized in that two or more photopolymerizable compounds are used in combination, and in the invention according to claim 5, the proportion of the photopolymerizable compound having one polymerization-reactive group. Is 0 to 50 mass% with respect to the photopolymerizable compound having two or more polymerization reactive groups.

The invention according to claim 7 is characterized in that the ink contains a vehicle, and the content of the vehicle is 1 to 50% by mass.

The following compounds can be mentioned as vehicles that can be used in the present invention.

As the room temperature solid wax, for example, petroleum wax, preferably paraffin wax or microcrystalline wax, mineral wax, preferably montan wax, ozokerite or ceresin,
Vegetable wax, preferably candelilla wax, carnauba wax, rice wax or jojoba solid wax, animal wax, preferably beeswax, lanolin or whale wax, synthetic hydrocarbon, preferably Fischer-Tropsch wax or polyethylene wax, Hydrogenated wax, preferably hydrogenated castor oil or hydrogenated castor oil derivative, modified wax, preferably montan wax derivative, paraffin wax derivative, microcrystalline wax derivative or polyethylene wax derivative, higher fatty acid, preferably behenic acid, stearic acid , Palmitic acid, myristic acid or lauric acid, higher alcohols, preferably stearyl alcohol or behenyl alcohol, hydroxystearic acid, preferably 12 Hydroxystearic acid or 1
2-hydroxystearic acid derivative, ketone, preferably stearone or laurone, fatty acid amide, preferably lauric acid amide, stearic acid amide, oleic acid amide, erucic acid amide, ricinoleic acid amide, 1
2-hydroxystearic acid amide, special fatty acid amide or N-substituted fatty acid amide, amine, preferably dodecylamine, tetradecylamine or octadecylamine, ester, preferably methyl stearate,
Examples thereof include octadecyl stearate, glycerin fatty acid ester, sorbitan fatty acid ester, propylene glycol fatty acid ester, ethylene glycol fatty acid ester or polyoxyethylene fatty acid ester, polymer wax, and preferably α-olefin maleic anhydride copolymer wax. Further, the above room temperature solid wax may be used alone or in combination of two or more kinds.

Among the above-mentioned normal temperature solid waxes, those having a particularly small polarity, such as paraffin wax, microcrystalline wax, ozokerite, ceresin, polyethylene wax, Fischer-Tropsch wax, stearone, lauron, methyl stearate, octadecyl stearate, etc. When used, it is desirable to use it as a mixture with other relatively polar wax. This disperses the pigments and dyes that are colorants,
The solubility is improved.

As the resin, for example, olefin resin, preferably polyethylene resin or polypropylene resin, vinyl resin, preferably ethylene-vinyl acetate copolymer resin, vinyl chloride-vinyl acetate copolymer resin, vinyl acetate resin. Or ethylene-vinyl chloride-vinyl acetate copolymer resin, acrylic resin, preferably methacrylic acid ester resin, polyacrylic acid ester resin,
Ethylene-ethyl acrylate copolymer resin or ethylene-methacrylic acid copolymer resin, phenol resin, polyurethane resin, polyamide resin, polyester resin, ketone resin, alkyd resin, rosin resin, petroleum resin, Examples include maleic acid resins and butyral resins. The above resins may be used alone or in combination of two or more.

The vehicle according to the present invention can be obtained by using the room temperature solid wax and the resin alone or in combination. Desirably, a room temperature solid wax is used as a basic component, and a resin is mixed as an additive for use.

In the present invention, the vehicle is characterized by a mass ratio of 1 to 50% with respect to the entire ink, and more preferably 1 to 20%. When it is more than 50%, the print quality is deteriorated.

As the colorant in the ink of the present invention, conventionally known dyes and pigments can be used. In the invention according to claim 2, the colorant used in the ink is a pigment,
The feature is that the amount of the pigment added is 0.5 to 30% by mass.

Examples of the water-soluble dye that can be used in the present invention include C.I. I. Direct black-
2, -4, -9, -11, -17, -19, -22,-
32, -80, -151, -154, -168, -17
1, -194; C.I. I. Direct Blue-1, -2,
-6, -8, -22, -34, -70, -71, -7
6, -78, -86, -112, -142, -165,
-199, -200, -201, -202, -203,
-207, -218, -236, -287; C.I. I. Direct Red-1, -2, -4, -8, -9, -1
1, -13, -15, -20, -28, -31, -3
3, -37, -39, -51, -59, -62, -6
3, -73, -75, -80, -81, -83, -8
7, -90, -94, -95, -99, -101, -1
10, -189; C.I. I. Direct Yellow-1,-
2, -4, -8, -11, -12, -26, -27,-
28, -33, -34, -41, -44, -48, -5
8, -86, -87, -88, -135, -142,-
144; C.I. I. Food Black-1, -2; C.I. I.
Acid Black-1, -2, -7, -16, -24,
-26, -28, -31, -48, -52, -63,-
107, -112, -118, -119, -121,-
156, -172, -194, -208; C.I. I. Acid Blue-1, -7, -9, -15, -22, -2
3, -27, -29, -40, -43, -55, -5
9, -62, -78, -80, -81, -83, -9
0, -102, -104, -111, -185, -24
9, -254; C.I. I. Acid Red-1, -4,-
8, -13, -14, -15, -18, -21, -2
6, -35, -37, -110, -144, -180,
-249, -257; C.I. I. Acid Yellow-1,
-3, -4, -7, -11, -12, -13, -14,
-18, -19, -23, -25, -34, -38,-
41, -42, -44, -53, -55, -61, -7
1, -76, -78, -79, -122 and the like.

The oil-soluble dyes include azo dyes, metal complex dyes, naphthol dyes, anthraquinone dyes, indigo dyes, carbonium dyes, quinoimine dyes, cyanine dyes, quinoline dyes, nitro dyes, nitroso dyes, benzoquinone dyes, naphthoquinone dyes, and naphthalene dyes. Phthalimide dye,
Examples include perinone dyes and phthalocyanine dyes,
It is not limited to these.

The water-insoluble dye and pigment according to the invention of claim 2 are not particularly limited,
Examples thereof include organic pigments, inorganic pigments, colored polymer particles, water-insoluble dyes, disperse dyes and oil-soluble dyes.

As the black pigment, furnace black,
Examples include carbon black pigments such as lamp black, acetylene black, and channel black.
Raven7000, Raven5750, Raven
5250, Raven5000 ULTRA II, Ra
ven3500, Raven2000, Raven15
00, Raven1250, Raven1200, Ra
ven1190 ULTRA II, Raven117
0, Raven1255, Raven1080, Rav
en1060 (above, Columbian Carbon Co., Ltd.),
Regal400R, Regal330R, Regal
660R, Mogul L, BlackPearls
L, Monarch700, Monarch800, M
onarch, 880, Monarch900, Mon
arch1000, Monarch1100, Mona
rch1300, Monarch1400 (above made by Cabot), Color Black FW1, Col
or Black FW2, Color Black
FW2V, Color Black 18, Color
Black FW200, Color Black
S150, Color Black S160, Col
or Black S170, Pritex35, Pr
itexU, Pritex Vrintex140U,
Printex140V, Special Black
6, Special Black5, Special
Black 4A, Special Black 4 (above, manufactured by Degussa), No. 25, no. 33, No.
40, No. 47, No. 52, No. 900, No.
2300, MCF-88, MA600, MA7, MA
8, MA100 (above, manufactured by Mitsubishi Chemical Co., Ltd.) and the like can be used. Further, magnetic fine particles such as magnetite and ferrite, titanium black and the like can be used as the black pigment.

Cyan pigments include C.I. I. Pigment Blue-1, C.I. I. Pigment Blue-2,
C. I. Pigment Blue-3, C.I. I. Pigment Blue-15, C.I. I. Pigment Blue-15:
1, C.I. I. Pigment Blue-15: 3, C.I. I.
Pigment Blue-15: 34, C.I. I. Pigment Blue-16, C.I. I. Pigment Blue-22,
C. I. Pigment Blue-60 and the like.

Examples of magenta pigments include C.I. I. Pigment Red-5, C.I. I. Pigment Red-7,
C. I. Pigment Red-12, C.I. I. Pigment Red-48, C.I. I. Pigment Red-4
8: 1, C.I. I. Pigment Red-57, C.I. I.
Pigment Red-112, C.I. I. Pigment Red-122, C.I. I. Pigment Red-123,
C. I. Pigment Red-146, C.I. I. Pigment Red-168, C.I. I. Pigment Red-
184, C.I. I. Pigment Red-202 and the like.

Examples of the yellow pigment include C.I. I. Pigment
Yellow-1, C.I. I. Pigment Yellow-2,
C. I. Pigment Yellow-3, C.I. I. Pigment yellow-12, C.I. I. Pigment Yellow-
13, C.I. I. Pigment Yellow-14, C.I. I.
Pigment yellow-16, C.I. I. Pigment Yellow-17, C.I. I. Pigment Yellow-73,
C. I. Pigment Yellow-74, C.I. I. Pigment Yellow-75, C.I. I. Pigment Yellow-83, C.I. I. Pigment Yellow-93, C.I.
I. Pigment Yellow-95, C.I. I. Pigment Yellow-97, C.I. I. Pigment Yellow-9
8, C.I. I. Pigment Yellow-114, C.I. I.
Pigment Yellow-128, C.I. I. Pigment
Yellow-129, C.I. I. Pigment Yellow-1
51, C.I. I. Pigment Yellow-154 and the like.

In addition to the above three primary color pigments of black and cyan, magenta and yellow, specific color pigments such as red, green, blue, brown and white, metallic luster pigments such as gold and silver, colorless extender pigment,
It is also possible to use a plastic pigment or the like. In addition to the above, a newly synthesized pigment may be used. Further, these pigments may be surface-treated. Examples of the surface treatment method include treatment with a coupling agent such as alcohol, acid, base and silane compound, polymer grafting treatment, and plasma treatment. The colorant used in the present invention preferably has a small content of organic and inorganic impurities. Generally, commercially available coloring agents have a high content of impurities, so it is desirable to use a purified product thereof. In the invention according to claim 2, the colorant used in the solid ink composition of the present invention is
The amount is 0.5 to 30% by mass with respect to the mass of the ink, but it is preferably 0.5 to 20% by mass, more preferably 0.5 to 10% by mass.

The invention according to claim 3 is characterized in that the pigment is a dispersion and the average dispersed particle diameter is 200 nm or less.

Examples of the dispersant used to disperse the pigment include higher fatty acid salts, alkyl sulfates, alkyl ester sulfates, alkyl sulfonates, sulfosuccinates, naphthalene sulfonates and alkyl phosphates. , Polyoxyalkylene alkyl ether phosphate,
Activator such as polyoxyalkylene alkyl phenyl ether, polyoxyethylene polyoxypropylene glycol, glycerin ester, sorbitan ester, polyoxyethylene fatty acid amide, amine oxide, or styrene, styrene derivative, vinylnaphthalene derivative, acrylic acid, acrylic acid Examples thereof include block copolymers, random copolymers and salts thereof composed of two or more monomers selected from derivatives, maleic acid, maleic acid derivatives, itaconic acid, itaconic acid derivatives, fumaric acid, fumaric acid derivatives. be able to.

As a method for dispersing the pigment, various methods such as a ball mill, a sand mill, an attritor, a roll mill, an agitator, a Henschel mixer, a colloid mill, an ultrasonic homogenizer, a pearl mill, a wet jet mill and a paint shaker can be used. It is also preferable to remove coarse particles from the pigment dispersion using a centrifugal separator or using a filter.

The average particle size of the pigment dispersion used in the ink of the present invention is 200 nm or less,
Preferably 10-200 nm, more preferably 10-
It is 100 nm.

The addition amount of the pigment dispersion used in the ink of the present invention is generally preferably in the range of 0.5 to 30% by mass, more preferably 1 to 20% by mass.

In the ink of the present invention, in addition to the above-mentioned additives, for example, a viscosity modifier, a reaction diluent, a filler, a flow aid, a thixotropic agent, a wetting agent, a defoaming agent, a plasticizer, etc. Other additives may be included. or,
A light stabilizer, an ultraviolet absorber, an antioxidant, a polymerization inhibitor, a stabilizer such as a corrosion inhibitor, or a Si compound, a wax or the like may be added.

If necessary, a water-soluble organic solvent can be added to the ink of the present invention. The water-soluble organic solvent preferably used, for example, alcohols (for example, methanol, ethanol, propanol, isopropanol, butanol, isobutanol, secondary butanol, tertiary butanol, pentanol, hexanol, cyclohexanol, benzyl alcohol, etc.), Polyhydric alcohols (for example, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol,
Dipropylene glycol, polypropylene glycol,
Butylene glycol, hexanediol, pentanediol, glycerin, hexanetriol, thiodiglycol, etc.), polyhydric alcohol ethers (eg ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol mono) Ethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, ethylene glycol monomethyl ether acetate, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, triethylene glycol monobutyl ether, ethylene glycol monophenyl ether Le, propylene glycol monophenyl ether), amines (e.g., ethanolamine, diethanolamine, triethanolamine, N-
Methyldiethanolamine, N-ethyldiethanolamine, morpholine, N-ethylmorpholine, ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, polyethyleneimine,
Pentamethyldiethylenetriamine, tetramethylpropylenediamine, etc.), amides (eg, formamide, N, N-dimethylformamide, N, N-dimethylacetamide, etc.), heterocycles (eg, 2-pyrrolidone, N-methyl-2-) Pyrrolidone, cyclohexylpyrrolidone, 2-oxazolidone, 1,3-dimethyl-2-
Examples thereof include imidazolidinone and the like), sulfoxides (for example, dimethyl sulfoxide and the like), sulfones (for example, sulfolane and the like), urea, acetonitrile, acetone and the like.

In the invention according to claim 8, the ink of the present invention is heated to 60 ° C. to 180 ° C., and ink is applied to the ink to eject ink droplets to form an image. The recording method is characterized in that an actinic ray is applied after the image is fixed on the recording medium kept. The temperature at which the ink droplets are ejected is 60 ° C.
180 ° C, but more preferably 80 ° C to 120 ° C
Is. Injection becomes difficult at 60 ° C or lower and 180 ° C or higher. Further, the temperature of the recording medium on which the ink droplets are ejected and on which an image is formed is 15 ° C. to 40 ° C., and when the temperature is 40 ° C. or higher, the deterioration of bleeding is large.

The invention according to claim 11 is characterized in that the piezoelectric force of a piezoelectric material having a wide range of application to ink is used as a driving force for ink ejection of an ink jet printer. Specifically, for example, as described in Japanese Patent Publication No. 4-48622, an electrode film is formed inside a fine groove formed on a piezoelectric substrate and further covered with an insulating film to form an ink flow path. Inkjet head method.

In the ink jet recording method of the present invention, light irradiation is performed after the ink composition is attached to the recording medium. The light irradiation may be visible light irradiation or ultraviolet irradiation, but the invention according to claim 9 is characterized in that the actinic ray is ultraviolet light. When performing UV irradiation, the UV irradiation amount is 100 mJ / cm ² or more, preferably 500.
mJ / cm ² or more and 10,000 mJ / c
m ² or less, preferably 5,000 mJ / cm ² or less. An ultraviolet irradiation amount within the above-mentioned range is advantageous because a sufficient curing reaction can be carried out and the colorant can be prevented from fading due to ultraviolet irradiation. Examples of the ultraviolet irradiation include lamps such as metal halide lamps, xenon lamps, carbon arc lamps, chemical lamps, low pressure mercury lamps, and high pressure mercury lamps.
For example, Fusion System H lamp, D
A commercially available lamp, V lamp, or the like can be used. The metal halide lamp has a continuous spectrum as compared with a high pressure mercury lamp (main wavelength is 365 nm), and has high luminous efficiency in the range of 200 to 450 nm.
Moreover, the long wavelength region is abundant. Therefore, when a pigment is used as in the ink composition of the present invention, a metal halide lamp is suitable.

The twelfth aspect of the invention is characterized in that the recording medium is non-ink absorbing.

The non-ink-absorbent recording medium in the present invention means a recording medium having no ink absorbing property, a recording medium having low ink absorbing property, or a surface made of a material having no ink absorbing property or a material having low ink absorbing property. Layer (printing layer)
Examples of the recording medium having a material having no ink absorbency or a material having low ink absorbability (or an ink non-absorbent material) are various plastics and metals.

Details of the ink jet recording apparatus of the present invention will be described below. FIG. 1 is a perspective view showing an example of the overall configuration of an inkjet recording apparatus of the present invention. An inkjet head 1 is mounted on a carriage 2, and the carriage 2 is driven so as to reciprocate left and right along guide rails 4 and 5 that are installed in parallel with each other so as to face the platen 3. The inkjet head 1 is connected to a connection line 6 made of a flexible substrate or the like for transmitting a recording signal pulse, and an ink tube 7 for supplying ink from the ink tank 8 to the inkjet head 1. During recording, the sub-scan is performed while the recording medium 9 is successively moved upward along the surface of the platen 3. Recording medium 9 by platen 3
Are sent upward, and ink droplets are ejected from a plurality of nozzles of the ink jet head 1 mounted facing each other in response to an image signal to form an image on the recording medium 9. Note that FIG.
Any conventionally known multi-channel inkjet head can be used as the inkjet head 1 used in the inkjet recording apparatus according to the embodiment shown in FIG.

Further, FIG. 1 is provided with a device for irradiating ultraviolet rays to a printed recording medium during or after recording (not shown in FIG. 1).

[0073]

EXAMPLES The present invention will be described in more detail by way of examples, but the present invention is not limited to the forms in these examples.

<< Preparation of Ink Composition >> [Preparation of Ink Unit 1: Present Invention] (Preparation of Black Ink 1) C.I. I. Pigment Black 7 (average dispersed particle diameter: 200 nm) 5 parts by mass Photopolymerizable compound: A-9300 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 75 parts by mass Photopolymerizable compound: EA-1020 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 15 parts by mass Diethylene glycol Addition amount to achieve viscosity (80 ° C.) described in Table 1 Sodium dimethylsulfosuccinate Addition amount to achieve surface tension described in NaOH NaOH Addition amount to achieve pH described in Table 1 Reaction initiator: Irgacure 184 (Japan Ciba Geigy 5 parts by mass After mixing the above compositions, the mixture is heated to 80 ° C. and mixed and stirred, and the resulting liquid is filtered under heating, and then cooled to obtain a viscous black ink (K). ) 1 was prepared. The viscosity was measured using a rotational viscometer (manufactured by Tokimec).

(Preparation of Cyan Ink 1) C.I. I. Pigment Blue 15: 3 (average dispersed particle diameter: 200 nm) 2.5 parts by mass Photopolymerizable compound: A-9300 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 75 parts by mass Photopolymerizable compound: EA-1020 (manufactured by Shin-Nakamura Chemical Co., Ltd.) ) 15 parts by mass Diethylene glycol Addition amount that gives the viscosity (80 ° C) shown in Table 1 Sodium dimethylsulfosuccinate Addition amount that gives the surface tension shown in NaOH NaOH Addition amount that gives the pH shown in Table 1 Reaction initiator: Irgacure 184 (manufactured by Nippon Ciba-Geigy Co., Ltd.) 7.5 parts by mass After mixing the above-mentioned respective compositions, the mixture was heated to 80 ° C. and mixed and stirred, and the obtained liquid was filtered through a filter under heating and then cooled and viscous. A cyan ink (C) 1 for the body was prepared.

(Preparation of Magenta Ink 1) C.I. I. Pigment Red 122 (average dispersed particle size: 200 nm) 3 parts by mass Photopolymerizable compound: A-9300 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 75 parts by mass Photopolymerizable compound: EA-1020 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 15 parts by mass Diethylene glycol Addition amount to achieve viscosity (80 ° C.) described in Table 1 Sodium dimethylsulfosuccinate Addition amount to achieve surface tension described in NaOH NaOH Addition amount to achieve pH described in Table 1 Reaction initiator: Irgacure 184 (Japan Ciba Geigy 7 parts by mass After mixing the above compositions, the mixture is heated to 80 ° C. and mixed and stirred, and the obtained liquid is filtered under heating, and then cooled to obtain a viscous magenta ink (M). ) 1 was prepared.

(Preparation of Yellow Ink 1) C.I. I. Pigment Yellow 93 (average dispersed particle diameter: 200 nm) 2.5 parts by mass Photopolymerizable compound: A-9300 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 75 parts by mass Photopolymerizable compound: EA-1020 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 15 Parts by mass Diethylene glycol Addition amount that gives the viscosity (80 ° C.) shown in Table 1 Sodium dimethylsulfosuccinate Addition amount that gives the surface tension shown in Table NaOH Addition amount that gives the pH shown in Table 1 Reaction initiator: Irgacure 184 ( 7.5 parts by mass After mixing the above respective compositions, the mixture was heated to 80 ° C. and mixed and stirred, and the obtained liquid was filtered through a filter under heating and then cooled to obtain a viscous substance. Yellow ink (Y) 1 was prepared.

[Preparation of Ink Unit 2: Present Invention] In the preparation of the black ink 1, the cyan ink 1, the magenta ink 1, and the yellow ink 1, the addition amount of diethylene glycol was appropriately changed so that the respective viscosities at 80 ° C. Black Ink 2, Cyan Ink 2, Magenta Ink 2 and Yellow Ink 2 were prepared in the same manner except that they were changed to 18, 20, 20, and 18 mPa · s.

[Preparation of Ink Unit 3: Present Invention] Same as in preparation of Black Ink 1, Cyan Ink 1, Magenta Ink 1, and Yellow Ink 1 except that the average dispersed particle diameter of each pigment was changed from 200 nm to 100 nm. Then, black ink 3, cyan ink 3, magenta ink 3, and yellow ink 3 were prepared.

[Preparation of Ink Unit 4: Present Invention] In the preparation of the above black ink 1, cyan ink 1, magenta ink 1, and yellow ink 1, the addition amount of each pigment is 15 parts by mass (B) and 12 parts by mass. Black ink 4, cyan ink 4, magenta ink 4, and yellow ink 4 were prepared in the same manner except that (C), 15 parts by mass (M), and 12 parts by mass (Y) were changed.

[Preparation of Ink Unit 5: Present Invention] (Preparation of Black Ink 5) C.I. I. Pigment Black 7 (average dispersed particle size: 200 nm) 5 parts by mass Photopolymerizable compound: A-9300 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 51 parts by mass Photopolymerizable compound: EA-1020 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 15 parts by mass Octyl acrylate 14 parts by mass Diethylene glycol Addition amount that gives the viscosity (80 ° C.) shown in Table 1 Sodium dimethylsulfosuccinate Addition amount that gives the surface tension shown in Table NaOH Addition amount that brings the pH shown in Table 1 Reaction initiator: Irgacure 184 (manufactured by Japan Ciba Geigy) 5 parts by mass After mixing the respective compositions, the mixture was heated to 80 ° C. and mixed and stirred, and the obtained liquid was filtered under heating, and then cooled to obtain a viscous substance. Black ink 5 was prepared.

(Preparation of Cyan Ink 5) C.I. I. Pigment Blue 15: 3 (average dispersed particle size: 200 nm) 2.5 parts by mass Photopolymerizable compound: A-9300 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 51 parts by mass Photopolymerizable compound: EA-1020 (manufactured by Shin-Nakamura Chemical Co., Ltd.) ) 15 parts by mass Octyl acrylate 14 parts by mass Diethylene glycol Addition amount that gives the viscosity (80 ° C.) shown in Table 1 Sodium dimethylsulfosuccinate Addition amount that gives the surface tension shown in Table 1 NaOH Addition amount that gives the pH shown in Table 1 Reaction initiator: Irgacure 184 (manufactured by Ciba-Geigy) 7.5 parts by mass After mixing the above compositions, the mixture was heated to 80 ° C. and mixed and stirred, and the obtained liquid was filtered under heating, and then filtered. After cooling, a viscous cyan ink 5 was prepared.

(Preparation of Magenta Ink 5) C.I. I. Pigment Red 122 (average dispersed particle diameter: 200 nm) 3 parts by mass Photopolymerizable compound: A-9300 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 51 parts by mass Photopolymerizable compound: EA-1020 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 15 parts by mass Octyl acrylate 14 parts by mass Diethylene glycol Addition amount that gives the viscosity (80 ° C.) shown in Table 1 Sodium dimethylsulfosuccinate Addition amount that gives the surface tension shown in Table NaOH Addition amount that brings the pH shown in Table 1 Reaction initiator: Irgacure 184 (manufactured by Japan Ciba Geigy) 7 parts by mass After mixing the above compositions, the mixture was heated to 80 ° C. and mixed and stirred, and the obtained liquid was filtered under heating, and then cooled to obtain a viscous substance. Magenta Ink 5 was prepared.

(Preparation of Yellow Ink 5) C.I. I. Pigment Yellow 93 (average dispersed particle size: 200 nm) 2.5 parts by mass Photopolymerizable compound: A-9300 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 51 parts by mass Photopolymerizable compound: EA-1020 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 15 Parts by mass Octyl acrylate 14 parts by mass Diethylene glycol Addition amount that results in viscosity (80 ° C.) shown in Table 1 Sodium dimethylsulfosuccinate Addition amount that results in surface tension shown in Table 1 NaOH Addition amount that results in pH shown in Table 1 Start of reaction Agent: Irgacure 184 (manufactured by Ciba Geigy) 7.5 parts by mass After mixing the above compositions, the mixture is heated to 80 ° C. and mixed and stirred, and the obtained liquid is filtered under heating and then cooled. To prepare viscous yellow ink 5.

[Preparation of Ink Unit 6: Present Invention] (Preparation of Black Ink 6) C.I. I. Pigment Black 7 (average dispersed particle diameter: 200 nm) 5 parts by mass Photopolymerizable compound: A-9300 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 90 parts by mass Diethylene glycol Amount added to give viscosity (80 ° C.) shown in Table 1 Dimethylsulfosuccinic acid Sodium Addition amount with surface tension shown in Table 1 NaOH Addition amount with pH shown in Table 1 Reaction initiator: Irgacure 184 (manufactured by Japan Ciba Geigy) 5 parts by mass After mixing the above compositions, the mixture was heated to 80 ° C. After heating and mixing and stirring, the obtained liquid was filtered under heating with a filter and then cooled to prepare a viscous black ink 6. The viscosity was measured using a rotational viscometer (manufactured by Tokimec).

(Preparation of Cyan Ink 6) C.I. I. Pigment Blue 15: 3 (average dispersed particle size: 200 nm) 2.5 parts by mass Photopolymerizable compound: A-9300 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 90 parts by mass Diethylene glycol Addition to achieve the viscosity (80 ° C.) described in Table 1. Amount Sodium dimethyl sulfosuccinate Amount to achieve surface tension shown in Table 1 NaOH Addition amount to achieve pH shown in Table 1 Reaction initiator: Irgacure 184 (manufactured by Ciba-Geigy Co., Ltd.) 7.5 parts by mass Mix each composition above After that, the mixture was heated to 80 ° C., mixed and stirred, and the obtained liquid was filtered under heating and then cooled to prepare a viscous cyan ink 6.

(Preparation of Magenta Ink 6) C.I. I. Pigment Red 122 (average dispersed particle size: 200 nm) 3 parts by mass Photopolymerizable compound: A-9300 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 90 parts by mass Diethylene glycol Amount added to give viscosity (80 ° C.) shown in Table 1 Dimethylsulfosuccinic acid Sodium Addition amount with surface tension shown in Table 1 NaOH Addition amount with pH shown in Table 1 Reaction initiator: Irgacure 184 (manufactured by Ciba-Geigy Co., Ltd.) 7 parts by mass After mixing the above compositions, the mixture was heated to 80 ° C. After heating and mixing and stirring, the obtained liquid was filtered under heating, and then cooled to prepare a viscous magenta ink 6.

(Preparation of Yellow Ink 6) C.I. I. Pigment Yellow 93 (average dispersed particle size: 200 nm) 2.5 parts by mass Photopolymerizable compound: A-9300 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 90 parts by mass Diethylene glycol Addition amount that gives viscosity (80 ° C.) shown in Table 1 Dimethyl Sodium sulfosuccinate Amount of surface tension listed in Table 1 NaOH Amount of pH listed in Table 1 Reaction initiator: Irgacure 184 (Nippon Ciba Geigy) 7.5 parts by mass After mixing the above compositions The mixture was heated to 80 ° C., mixed and stirred, and the obtained liquid was filtered under heating and then cooled to prepare a viscous yellow ink 6.

[Preparation of Ink Unit 7: Present Invention] In the preparation of the black ink 1, the cyan ink 1, the magenta ink 1, and the yellow ink 1, the pH of each is adjusted to 6.5 by appropriately changing the addition amount of NaOH. From 4.5
Black ink 7, cyan ink 7, magenta ink 7, and yellow ink 7 were prepared in the same manner except that the above was changed to.

[Preparation of Ink Unit 8: Present Invention] (Preparation of Black Ink 8) C.I. I. Pigment Black 7 (average dispersed particle size: 200 nm) 5 parts by mass Photopolymerizable compound: A-9300 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 55 parts by mass Photopolymerizable compound: EA-1020 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 15 parts by mass Vehicle: Carnauba wax 20 parts by mass Diethylene glycol Addition amount that gives the viscosity (80 ° C.) shown in Table 1 Sodium dimethylsulfosuccinate Addition amount that gives the surface tension shown in Table 1 NaOH Addition amount that gives the pH shown in Table 1 Start of reaction Agent: Irgacure 184 (manufactured by Ciba-Geigy Co., Ltd.) 5 parts by mass After mixing each composition described above, the mixture was heated to 80 ° C. and mixed and stirred, and the obtained liquid was filtered under heating, and then cooled and viscous. A black ink 8 having a hollow body was prepared.

(Preparation of Cyan Ink 8) C.I. I. Pigment Blue 15: 3 (average dispersed particle size: 200 nm) 2.5 parts by mass Photopolymerizable compound: A-9300 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 55 parts by mass Photopolymerizable compound: EA-1020 (manufactured by Shin-Nakamura Chemical Co., Ltd.) ) 15 parts by mass Vehicle: Carnauba wax 20 parts by mass Diethylene glycol Addition amount that gives the viscosity (80 ° C) shown in Table 1 Sodium dimethylsulfosuccinate Addition amount that gives the surface tension shown in Table 1 NaOH It becomes the pH value shown in Table 1. Addition amount Reaction initiator: Irgacure 184 (manufactured by Nippon Ciba Geigy) 7.5 parts by mass After mixing the above respective compositions, the mixture was heated to 80 ° C. and mixed and stirred, and the obtained liquid was filtered under heating. Then, it was cooled to prepare a viscous cyan ink 8.

(Preparation of Magenta Ink 8) C.I. I. Pigment Red 122 (average dispersed particle diameter: 200 nm) 3 parts by mass Photopolymerizable compound: A-9300 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 55 parts by mass Photopolymerizable compound: EA-1020 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 15 parts by mass Vehicle: Carnauba wax 20 parts by mass Diethylene glycol Addition amount that gives the viscosity (80 ° C.) shown in Table 1 Sodium dimethylsulfosuccinate Addition amount that gives the surface tension shown in Table 1 NaOH Addition amount that gives the pH shown in Table 1 Start of reaction Agent: Irgacure 184 (manufactured by Japan Ciba Geigy) 7 parts by mass After mixing each composition described above, the mixture was heated to 80 ° C. and mixed and stirred, and the obtained liquid was filtered under heating with filtration, and then cooled and viscous. A magenta ink 8 having a hollow body was prepared.

(Preparation of Yellow Ink 8) C.I. I. Pigment Yellow 93 (average dispersed particle diameter: 200 nm) 2.5 parts by mass Photopolymerizable compound: A-9300 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 55 parts by mass Photopolymerizable compound: EA-1020 (manufactured by Shin-Nakamura Chemical Co., Ltd.) 15 Parts by mass Vehicle: Carnauba wax 20 parts by mass Diethylene glycol Addition amount that gives the viscosity (80 ° C.) shown in Table 1 Sodium dimethylsulfosuccinate Addition amount that gives the surface tension shown in Table 1 NaOH Addition amount that gives the pH shown in Table 1 Reaction initiator: Irgacure 184 (manufactured by Ciba-Geigy) 7.5 parts by mass After mixing the above compositions, the mixture was heated to 80 ° C. and mixed and stirred, and the obtained liquid was filtered under heating, and then filtered. After cooling, viscous yellow ink 8 was prepared.

[Preparation of Ink Unit 9: Comparative Example] (Preparation of Black Ink 9) C.I. I. Pigment Black 7 5 parts by mass Paraffin wax: manufactured by Nippon Seiro Co., Ltd. 155 40 parts by mass Behenic acid: manufactured by Wako Pure Chemical Industries, Ltd. 35 parts by mass Oleic acid amide: manufactured by Kao Fatty Acid Amide ON 20 parts by mass Sodium dimethylsulfosuccinate Addition amount that becomes surface tension NaOH
Addition amount to achieve pH shown in Table 1 Each of the above additives was heated to 150 ° C. and mixed to prepare Black Ink 9. The viscosity of black ink 9 at 80 ° C is 15m.
It was Pa · s. The measurement of pH and surface tension is
Each was carried out at 140 ° C.

(Preparation of Cyan Ink 9) C.I. I. Pigment Blue 15: 3 2.5 parts by mass Paraffin wax: Nippon Seiro Co., Ltd. 155 40 parts by mass Behenic acid: Wako Pure Chemical Industries, Ltd. 37.5 parts by mass Oleic acid amide: Kao company fatty acid amide ON 20 parts by mass Dimethylsulfosuccinic acid Sodium Addition Amount with Surface Tension Shown in Table 1 NaOH Addition Amount with pH Shown in Table 1 Each of the above additives was heated to 150 ° C. and mixed to prepare cyan ink 9. The viscosity of cyan ink 9 at 80 ° C. was 18 mPa · s. The pH and surface tension were measured at 140 ° C.

(Preparation of Magenta Ink 9) C.I. I. Pigment Red 122 3 parts by mass Paraffin wax: manufactured by Nippon Seiro Co., Ltd. 155 40 parts by mass Behenic acid: manufactured by Wako Pure Chemical Industries, Ltd. 37 parts by mass Oleic acid amide: manufactured by Kao Corporation Fatty acid amide ON 20 parts by mass Sodium dimethylsulfosuccinate Addition Amount for Surface Tension NaOH Addition Amount for pH to be listed in Table 1 Each of the above additives was heated to 150 ° C. and mixed to prepare magenta ink 9. The viscosity of magenta ink 9 at 80 ° C. was 17 mPa · s. The pH and surface tension were measured at 140 ° C.

(Preparation of Yellow Ink 9) C.I. I. Pigment Yellow 93 2.5 parts by mass Paraffin wax: manufactured by Nippon Seiro Co., Ltd. 155 40 parts by mass Behenic acid: manufactured by Wako Pure Chemical Industries, Ltd. 37.5 parts by mass Oleic acid amide: manufactured by Kao Corporation Fatty acid amide ON 20 parts by mass Sodium dimethylsulfosuccinate table 1. Addition amount with which the surface tension described in 1 was obtained NaOH Addition amount with which the pH described in Table 1 was obtained Each of the above additives was heated to 150 ° C. and mixed to prepare yellow ink 9. The viscosity of the yellow ink 9 at 80 ° C. was 14 mPa · s. The pH and surface tension were measured at 140 ° C.

[Preparation of Ink Unit 10: Comparative Example] (Preparation of Black Ink 10) C.I. I. Pigment Black 7 5 parts by mass 1,6-hexanediol diacrylate 50 parts by mass 2-phenoxyethyl acrylate 35 parts by mass Reaction Initiator: Irgacure 184 (manufactured by Ciba-Geigy Japan) 5 parts by mass Sodium dimethylsulfosuccinate Surface shown in Table 1 Addition amount that becomes tension NaOH Addition amount that gives the pH described in Table 1 2-phenoxyethanol 5 parts by mass Each of the above additives was mixed to prepare a black ink 10. The viscosity of the black ink 10 at 80 ° C. is 13
It was mPa · s.

(Preparation of Cyan Ink 10) C.I. I. Pigment Blue 15: 3 2.5 parts by mass 1,6-hexanediol diacrylate 50 parts by mass 2-phenoxyethyl acrylate 35 parts by mass Reaction Initiator: Irgacure 184 (manufactured by Ciba-Geigy Japan) 7.5 parts by mass Sodium dimethylsulfosuccinate Amount of addition that gives the surface tension shown in Table 1 NaOH amount of the addition that gives the pH shown in Table 1 2-phenoxyethanol 5 parts by mass The above-mentioned additives were mixed to prepare a cyan ink 10.
The viscosity of cyan ink 10 at 80 ° C. is 15 mPas.
・ It was s.

(Preparation of Magenta Ink 10) C.I. I. Pigment Red 122 3 parts by mass 1,6-hexanediol diacrylate 50 parts by mass 2-phenoxyethyl acrylate 35 parts by mass Reaction initiator: Irgacure 184 (manufactured by Japan Ciba Geigy) 7 parts by mass Sodium dimethylsulfosuccinate Addition amount to be tension NaOH Addition amount to have pH shown in Table 1 2-phenoxyethanol 5 parts by mass The above-mentioned additives were mixed to prepare a magenta ink 10. The viscosity of magenta ink 10 at 80 ° C. is 14
It was mPa · s.

(Preparation of Yellow Ink 10) C.I. I. Pigment Yellow 93 2.5 parts by mass 1,6-hexanediol diacrylate 50 parts by mass 2-phenoxyethyl acrylate 35 parts by mass Reaction initiator: Irgacure 184 (manufactured by Japan Ciba Geigy) 7.5 parts by mass Sodium dimethylsulfosuccinate Table 1 The amount of addition that gives the surface tension described in 1. NaOH The amount of addition that results in the pH of Table 1 2-phenoxyethanol 5 parts by mass The above-mentioned additives were mixed to prepare a yellow ink 10. The viscosity of the yellow ink 10 at 80 ° C. is 10
It was mPa · s.

[Preparation of Ink Unit 11: Comparative Example] In the preparation of Black Ink 1, Cyan Ink 1, Magenta Ink 1 and Yellow Ink 1, the surface tension of each of them was changed by appropriately changing the addition amount of sodium dimethylsulfosuccinate. Was changed to 18, 19, 19, 18 mN / m, and black ink 11,
Cyan ink 11, magenta ink 11, and yellow ink 11 were prepared.

[Measurement of Viscosity of Each Ink at 25 ° C.] The viscosity at 25 ° C. of each of the color inks of the ink units 1 to 11 prepared above was measured by a rotational viscometer (manufactured by Tokimec).
Table 1 shows the obtained results. In addition, since each color ink of the ink unit 9 was in a solid state at 25 ° C., the measurement was not performed.

[0104]

[Table 1]

<Image Recording Method> (Inkjet Printer) The inkjet recording apparatus having the configuration shown in FIG. 1 was used as an inkjet printer.

(Recording Medium) A polyethylene terephthalate (PET) sheet having a thickness of 60 μm was used. During printing, the PET sheet was kept at room temperature (25 ° C).

(Output of Image) Each of the prepared ink units was housed in a dedicated ink cartridge, each was loaded in an ink jet printer, and output to the recording medium. The ink unit 11 of the present invention and the comparative ink unit 11 were held at an ink temperature of 80 ° C., the ink unit 9 at 150 ° C., and the ink unit 10 at room temperature for printing.

The printing conditions for each color were set as follows as target densities for each color, and 8-point characters and solid images were printed.

Yellow Density: 1.04 Magenta Density: 1.53 Cyan Density: 1.48 Black Density: 1.83 In addition, the colorimetry of each of the above-mentioned colors is carried out by using a colorimeter (spectrolino key wizard manufactured by Gretag Macbeth Co.). It carried out on condition of the following.

Light source: D50 Field of view: 2 ° Field density: ANSI T White reference: abs Filter: No-filter (UV irradiation treatment) After printing out on a recording medium as described above, UV irradiation is performed under the following conditions. gave.

The ultraviolet irradiation lamp used was a metal halide type having a wavelength of 365 nm, and ultraviolet irradiation was performed at an ultraviolet irradiation amount of 1,000 mJ / cm ² .

<< Evaluation of Output Image >> (Evaluation of character quality) Using each color ink of Y, M, C, and K, a 6-point MS Mincho character is printed at a target density, and the rubbing of the character is magnified and evaluated with a magnifying glass. Then, the character quality was evaluated according to the following criteria.

⊚: No rustiness ○: Slight rustle is visible Δ: Roughness is visible, but can be discerned as a character and can be used as close as possible ×: Level that is terribly rusty and the character is faint and cannot be used (color mixture (bleeding)) (Evaluation) Adjacent color dots printed with Y, M, C, and K inks were magnified with a magnifying glass, the degree of bleeding was visually observed, and color mixing was evaluated according to the following criteria.

⊚: Adjacent dot shapes maintain a perfect circle and no blurring ○: Adjacent dot shapes maintain a nearly perfect circle and almost no blurring Δ: Adjacent dot shapes are slightly blurred and the dot shapes are slightly distorted However, the level at which it can be used at the last minute x: Adjacent dots are mixed with each other and cannot be used (evaluation of image durability) After printing a solid image of each color, the formed image is transferred to Tokubishi Art and scratch strength Testing machine H
The scratch strength was measured using EIDON-18 (manufactured by HEIDON) and the measuring needle was a 0.8 mmR sapphire needle. For the measurement, a 10 cm scratching test was performed three times under a constant load, and the limit load at which there was no scratched portion up to the support was defined as scratch strength, and the image durability was evaluated based on the measured values according to the following criteria.

◯: Scratch strength is 200 g or more Δ: Scratch strength is 100 to less than 200 g ×: Scratch strength is less than 100 g (evaluation of ink storability) Each of the prepared inks was put in a test tube. After standing at 80 ° C. for 3 days, the sedimentation state was visually observed according to the criteria described below.

◯: No sedimentation of pigment was found in the ink and no effect on printing Δ: Pigment sedimentation was found in the ink but no effect on printing X: Sedimentation of a large amount of pigment in the ink Table 2 shows each evaluation result obtained at a level above the level at which the printing was disturbed.

[0117]

[Table 2]

As is clear from Table 2, the viscosity is 25 ° C.
At 500 to 50,000 mPa · s at 80 ° C for 3 to 30
The ink of the present invention having mPa · s and a surface tension in the range of 20 to 60 mN / m is superior to the comparative product in character quality,
It can be seen that color mixing, image durability and ink storability are excellent.

[0119]

According to the present invention, it is possible to provide an ink excellent in ink stability, bleeding resistance, ink storability and stability (rubbing resistance) after printing, and a recording method and an inkjet recording method using the same. did it.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of an inkjet recording apparatus according to the present invention.

[Explanation of symbols]

1 inkjet head 2 carriage 3 Platen 4,5 guide rail 7 ink tubes 8 ink tanks 9 recording media 20 cap

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) B41J 3/04 101Z F term (reference) 2C056 EA13 EC21 EC29 FA04 FC02 HA44 2H086 BA05 BA18 BA19 BA55 BA59 BA60 BA61 BA62 4J039 AB12 AD03 AD06 AD21 AD23 AE05 BC20 BE01 BE02 BE22 BE27 EA06 EA36 EA44 EA47 GA24

Claims (13)

[Claims] 1. An ink containing at least a photopolymerizable compound, a photopolymerization initiator and a colorant, wherein the viscosity of the ink is 500 to 50000 mPa · s at 25 ° C.
An ink having a temperature of 3 to 30 mPa · s at a temperature of 20 ° C. and a surface tension of 20 to 60 mN / m. 2. The colorant is a pigment, and the amount of the pigment added is 0.5 to 30% by mass.
Ink described in. 3. The pigment is a dispersion, and the average dispersed particle diameter is 200 nm or less.
Ink described in. 4. The ink according to claim 1, wherein two or more photopolymerizable compounds are used in combination. 5. The ratio of the photopolymerizable compound having one polymerization reactive group is 0 to 50% by mass with respect to the photopolymerizable compound having two or more polymerization reactive groups. Item 4. The ink according to Item 4. 6. The ink according to claim 1, wherein the pH of the ink is 4 to 10. 7. A vehicle containing a vehicle, wherein the content of the vehicle is 1 to 50% by mass.
The ink according to any one of 1. 8. The ink according to claim 1 is heated to 60 ° C. to 180 ° C., and jetting energy is applied to the ink to jet ink droplets.
A recording method comprising applying an actinic ray after fixing an image on a recording medium at 15 ° C to 40 ° C. 9. The recording method according to claim 8, wherein the actinic ray is an ultraviolet ray. 10. An ink jet recording method using the ink according to any one of claims 1 to 7, wherein ink droplets formed by an ink jet method are attached to a recording medium to perform recording. 11. The ink jet recording method according to claim 10, wherein the ink jet method is a method utilizing a piezoelectric action of a piezoelectric body. 12. The ink jet recording method according to claim 10, wherein the recording medium is non-ink-absorbent. 13. The ink attached to the recording medium,
The inkjet recording method according to claim 10, further comprising a step of applying ultraviolet rays.