JPH0987562A - Ink jet recording ink - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an ink jet recording ink which can cope with ink jet printers provided with different jetting mechanisms by mixing a specified colorant with a specified dispersant and a specified solvent. SOLUTION: This ink jet recording ink comprises a pigment as a colorant, a derivative of a polyoxyethylene ether phosphate, represented by the formula (wherein R is an alkyl, an alkenyl or an aryl; and M is a base) and used as a dispersion agent for the pigment and water or a water/hydrophilic solvent (e.g. ethanol or isopropanol) mixture as a liquid solvent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording ink, and more particularly to an ink jet recording ink applicable to ink jet printers having different ejection mechanisms.

[0002]

2. Description of the Related Art An ink jet recording system is divided by a mechanism for ejecting ink, and a bubble jet system or a thermal jet system in which ink is ejected by bubbles generated by heat, and a piezo system in which ink is ejected by vibration of a piezo element. In either method, a recorded image is obtained by intermittently ejecting ink droplets from a fine nozzle.

As an ink used in such an ink jet recording system, an ink in which a dye such as a dye or a pigment is dissolved or dispersed in a liquid medium made of a mixed system of water or a hydrophilic organic solvent is used.

As the coloring matter in this ink, the pigment used as insoluble fine particles is considerably more advantageous than the dye used in a dissolved state in terms of water resistance and light resistance of a recorded image, but in the ink jet recording system. Since the ink is ejected from a fine nozzle, if the pigment is not dispersed and stabilized in the form of fine particles, clogging may occur in the nozzle or the pigment may agglomerate when the ink is stored for a long time, resulting in ejection failure. Cause of.

Further, the finer the particle size, the stronger the cohesion of the pigments with each other. Therefore, the pigment dispersion stabilizing performance of the dispersant itself is such a high performance that the pigment is dispersed very finely and the stability is maintained for a long period of time. Is required.

Further, as described above, the ink which can be applied to various methods such as the bubble jet method, the thermal ink jet method, the piezo method, etc. is a feather caused by the ink ejection failure due to the charring of the ink or the improved ink ejection performance. It was difficult to obtain satisfactory performance due to the problems peculiar to inkjet printers that originated from the ejection mechanism such as the ring.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned conventional drawbacks, and in the case of using a pigment having excellent light resistance and water resistance as compared with a dye as a colorant. It is an object of the present invention to provide an excellent inkjet recording ink that maintains long-term dispersion stability without deteriorating various properties as an ink and that is compatible with inkjet printers having various ejection mechanisms.

[0008]

The ink for ink jet recording of the present invention comprises at least two kinds of polyoxyethylene ether phosphate salt derivative represented by the following general structural formula, a pigment, and water or a hydrophilic solvent as a liquid medium. It is composed of a mixed system of. Structural formula R: alkyl group, alkenyl group, aryl group M:
base

Derivatives of polyoxyethylene ether phosphate salts include polyoxyethylene alkyl ether phosphate salts, polyoxyethylene alkenyl ether ether phosphate salts, and polyoxyethylene aryl ether phosphate salts having a polyoxyethylene polymerization degree of 2 to 25. As the base for phosphate, alkali metals such as potassium and sodium, alkaline earth metals such as calcium and barium, and amines such as ammonia, monoethanolamine, diethanolamine, triethanolamine and the like can be mentioned.

Regarding the alkyl or alkenyl of the polyoxyethylene alkyl ether phosphate salt or the polyoxyethylene alkenyl ether phosphate salt, an alkane compound or alkene compound having a carbon chain of 2 to 24 is preferable, and a 2-ethylhexyl group, dodecyl group, tridecyl group, hexadecyl group is preferable. A group, an octadecyl group, an allyl group and an oleyl group are particularly preferable.

The aryl of the polyoxyethylene aryl ether phosphate salt has 8 to 20 carbon atoms.
Is preferred, and an octylphenyl group, a nonylphenyl group, a styrenephenyl group and the like are particularly preferred.

The pigments used include carbon black, phthalocyanine-based, threne-based, azo-based, quinacridone-based, dioxazine-based, anthraquinone-based, indigo-based, thioindigo-based, azomethine-based, perylene, perinone-based and isoindolinone-based. , Titanium oxide, and other metal oxides.

The solvent used for the liquid medium is water,
Alternatively, a mixture of water and hydrophilic solvent can be used. Examples of the hydrophilic organic solvent include alcohols such as ethanol, normal propanol, isopropanol, normal butanol, secondary butanol, and cyclohexanol, monoethanolamine, diethanolamine, triethanolamine, N, N-dimethylethanolamine, aminoethylethanolamine, Alkanolamines such as morpholine, polyhydric alcohols such as ethylene glycol, diethylene glycol, tripropylene glycol, glycerin, ethylene glycol dimethyl ether, ethylene glycol monomethyl ether, triethylene glycol monomethyl ether, ethylene glycol monobutyl ether, triethylene glycol monoethyl ether. , Triethylene glycol monobutyl ether, tryp Glycol ethers such as propylene glycol monomethyl ether, and the like.

The above-mentioned polyoxyethylene alkyl (or alkenyl, aryl) ether phosphate salt, pigment, water and hydrophilic solvent may satisfy desired properties such as mutual affinity, pigment dispersion stability and viscosity. It is the one that is selected and used.

The proportion of the pigment used in the ink-jet recording ink of the present invention may be any concentration as long as it gives a sufficient coloring density to the recording medium, but generally from 1 to 1 in the ink composition. A proportion of 10% by weight is preferable.

The amount of the polyoxyethylene alkyl (or alkenyl, aryl) ether phosphate salt used in the ink jet recording ink varies depending on the type and brand of the pigment and can be generally defined by the influence on the viscosity of the ink jet recording ink. However, it is preferable to use the pigment in an amount of about 10 to 100 parts by weight based on 100 parts by weight of the pigment.

Water and a hydrophilic solvent are used as the liquid solvent, and the hydrophilic solvent is preferably used in a proportion of 0 to 100 parts by weight relative to 100 parts by weight of water. Further, in the present invention, other known additives can be added as necessary.

The ink jet recording ink of the present invention comprises the above-mentioned components and blends, and various production methods can be adopted. For example, the above various components are blended, and the pigment is mixed and milled by a conventionally known disperser such as a ball mill, a sand grinder mill, a speed line mill, and a roll mill, and then the physical properties such as concentration and particle size are adjusted and filtered. Ink can be obtained by removing coarse particles by centrifugation or the like.

The present invention will be described below with reference to examples. In the text, parts are based on weight unless otherwise specified.

(Example 1) Carbon black 30.0 parts (trade name MA-100 manufactured by Mitsubishi Chemical) polyoxyethylene lauryl ether sodium phosphate 10.0 parts (trade name Nikkor DLP-10 manufactured by Nikko Chemicals) ethylene glycol 28 0.0 parts Water 80.0 parts Preservative (product name Proxel GXL ICI) 2.0 parts After mixing the above components, dispersion treatment was carried out with a ball mill to obtain a carbon black dispersion liquid. Glycerin 50.0 parts Diethylene glycol 150.0 parts 48% Sodium hydroxide 2.0 parts Water 648.0 parts were added to this carbon black dispersion and mixed and stirred, followed by centrifugation to remove coarse particles and pigment concentration of 3.0. % Ink for inkjet printers was obtained.

(Example 2) Carbon black 30.0 parts (trade name Raven 1255 Colombian Carbon Japan) dipolyoxyethylene nonylphenyl ether phosphate 10.0 parts (trade name PRYSURF A207H manufactured by Daiichi Kogyo Seiyaku Co., Ltd.) Ethylene glycol 30.0 parts Ammonia water 2.0 parts Water 80.0 parts Preservative (trade name: Proxel GXL ICI) 2.0 parts After mixing the above components, dispersion treatment is carried out with a ball mill to obtain a carbon black dispersion liquid. It was To this carbon black dispersion, glycerin 200.0 parts propylene glycol 50.0 parts water 596.0 parts were added, mixed and stirred, and then centrifuged to remove coarse particles to obtain an ink for an ink jet printer having a pigment concentration of 3.0%. It was

Example 3 Benzidine yellow 40.0 parts (trade name Shimura Fast Yellow RF, manufactured by Dainippon Ink) Polyoxyethylene lauryl ether monoethanolamine phosphate 15.0 parts (trade name PRYSURF M208B Daiichi Kogyo Seiyaku Co., Ltd.) Ethylene glycol 40.0 parts Water 53.0 parts Preservative 2.0 parts (trade name Proxel GXL ICI product) After mixing the above components, dispersion treatment was carried out with a sand grinder mill to obtain a benzidine yellow dispersion liquid. To this benzidine yellow dispersion, 200.0 parts of diethylene glycol and 650.0 parts of water were added, mixed and stirred, and then centrifuged to remove coarse particles to obtain an ink for an inkjet printer having a pigment concentration of 4.0%.

(Example 4) Quinacridonelet 30.0 parts (trade name: Fastgen Super Magenta RE-01, made by Dainippon Ink) 15.0 parts dipolyoxyethylene nonylphenyl ether ether phosphate (trade name: Nikkor DNPP-4 Nikko) Chemicals) Ethylene glycol 30.0 parts 48% sodium hydroxide 1.0 part Water 72.0 parts Preservative (trade name Proxel GXL ICI) 2.0 parts After mixing the above components, dispersion treatment with a sand grinder mill Then, a quinacridone red dispersion liquid was obtained. Glycerin 200.0 parts Ammonia water 2.0 parts Water 648.0 parts was added to this quinacridone red dispersion liquid, mixed and stirred, and then centrifuged to remove coarse particles to obtain an ink for an inkjet printer having a pigment concentration of 3.0%. It was

(Example 5) Phthalocyanine blue 20.0 parts (trade name: Lionol Blue FG-7330 manufactured by Toyo Ink) Tripolyoxyethylene alkyl ether phosphoric acid 10.0 parts (trade name: Nikkor TDP-8 manufactured by Nikko Chemicals) ethylene Glycol 20.0 parts Triethanolamine 2.0 parts Water 96.0 parts Preservative (product name Proxel GXL ICI) 2.0 parts After mixing the above components, dispersion treatment is carried out with a sand grinder mill and phthalocyanine blue dispersion liquid. Got To this phthalocyanine blue dispersion, there were added siethien glycol 200.0 parts ethylene glycol dimethyl ether 10.0 parts triethanolamine 5.0 parts water 635.0 parts, followed by mixing and stirring and centrifuging to remove coarse particles, and pigment concentration 2 0.0% ink for inkjet printers was obtained.

Comparative Example 1 An ink for an ink jet printer was obtained in the same manner as in Example 1 except that polyoxyethylene lauryl ether (trade name, Emulgen 120, manufactured by Kao Corporation) was added instead of the dispersant of Example 1. .

Comparative Example 2 An ink for an ink jet printer was obtained in the same manner as in Example 2 except that polyoxyethylene oleyl ether (trade name, Emulgen 420, manufactured by Kao Corporation) was added instead of the dispersant of Example 2. .

Comparative Example 3 β was used in place of the dispersant of Example 3.
An ink for an inkjet printer was obtained in the same manner as in Example 3 except that a sodium salt of sodium naphthalenesulfonic acid condensate (trade name, Demol N Kao) was added.

(Comparative Example 4) 40.0 parts of a styrene-α-methylsulfonic acid-acrylic acid copolymer (trade name: Johncryl 62 active ingredient 34%, manufactured by Johnson Polymer) was dispersed in place of the dispersant of Example 4. 72. add water before
An ink for inkjet printer was obtained in the same manner as in Example 4 except that the content was changed from 0 part to 47.0 parts.

(Comparative Example 5) Instead of the dispersant of Example 5, polyvinylpyrrolidone (trade name: Rubiscol K-30) was used.
An ink for inkjet printer was obtained in the same manner as in Example 5 except that the active ingredient (95% manufactured by BASF) was blended.

Example 6 Each of the inks of Examples 1 to 5 and Comparative Examples 1 to 5 was filled in a bubble jet type, thermal ink jet type, or piezo type ink jet printer, and the ink discharge status and printing were performed. The condition was observed. For each inkjet printer, the bubble jet method is used by Canon BJ
C-820, Japan HP for thermal inkjet system
DeskJet 505J manufactured by Epson and MJ500C manufactured by Epson were used for the piezo method.

[0031]

The present invention can take various changes and modifications to the method and product. The various embodiments described above are for the purpose of further clarifying the content of the present invention and not for limiting the present invention.

As described above, according to the present invention, water resistance,
It is possible to obtain an excellent inkjet recording ink which has excellent light resistance and can be applied to inkjet printers having different ejection mechanisms.

Claims (1)

[Claims] 1. A colorant, a pigment, a polyoxyethylene ether phosphate salt derivative represented by the following structural formula as a pigment dispersant, water as a liquid solvent, or a mixed system of water and a hydrophilic solvent. Characteristic ink for inkjet recording. Structural formula R: alkyl group, alkenyl group, aryl group M:
base