JPH10219157A - Recording fluid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an ink jet pigmented water-base recording fluid which is made proof against the growth of mold even after long-term storage, shows good delivery and high reliability of recording and can give a recording having good water resistance and light resistance even on plain paper by mixing an aqueous medium with a pigment and glutaraldehyde being an antimold showing excellent effectiveness. SOLUTION: This fluid contains 100-5,000ppm, desirably 500-1,500ppm, based on the entire weight of the fluid, of glutaraldehyde. The carbon black used as the pigment of the fluid may be a commercially available one having a primary particle diameter of 10-100nm, a DBP absorption of 40-150nm/100g and a pH of 3-9. The pigments other than the carbon black may be commercially available ones. It is desirable that the fluid further contains a dispersant such as a surfactant or a polymeric dispersant. The aqueous medium mainly consists of water and desirably, further contains a water-soluble organic solvent such as ethylene glycol, N-methylpyrrolidone or ethanol.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aqueous medium recording liquid, and more particularly to a recording liquid suitable for ink jet or writing implements.

[0002]

2. Description of the Related Art Conventionally, as a recording liquid for ink jet recording, an aqueous ink in which an acidic dye or a direct dye is dissolved in an aqueous medium, or a solvent-based ink in which an oil-soluble dye is dissolved in an organic solvent has been used. . Since the solvent-based ink uses a solvent, it has a problem in terms of environmental safety, and its use is limited and cannot be used in offices and the like. On the other hand, since the water-based ink uses a water-soluble pigment, there is a problem that the recorded matter has poor water resistance, particularly when recorded on plain paper. Further, the recorded matter of the ink using these dyes is insufficient in light resistance. The same applies to the recording liquid for writing instruments.

In order to solve the above-mentioned problems, a pigment having excellent water resistance and light resistance is used as a coloring material, and an aqueous dispersion ink in which the pigment is dispersed in an aqueous medium is partially used. However, if these recording liquids are left for a long period of time, fungi will proliferate, which is one of the causes of clogging. Therefore, it is generally considered preferable to add an antifungal agent ( JP-A-3-62864). However, depending on the fungicide used, the dispersion stability of the pigment may be impaired, and the pigment may aggregate during storage.

[0004]

SUMMARY OF THE INVENTION The present invention has a good water resistance, a good ejection property, a high recording reliability, and a high printing quality for recording on plain paper for ink jet recording or writing instruments. The purpose is to provide an aqueous dispersion ink using a pigment that has good fastness other than water resistance such as quality and light fastness, and that has good stability when stored for a long time. is there.

[0005]

That is, the gist of the present invention resides in a recording liquid characterized by containing an aqueous medium, a pigment and glutaraldehyde.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The present inventors have conducted tests on various fungicides with respect to the fungicide for recording liquid, and as a result, have found that the glutaraldehyde exhibits a particularly excellent effect as a fungicide. It is. The recording liquid prepared using these compounds has good ejection stability at the time of recording, print quality of the recorded matter, and good recording stability other than water resistance such as light resistance, and the recording liquid can be used. It has good stability, and does not cause sedimentation of the pigment during long-term storage.

Glutaraldehyde used in the recording liquid of the present invention is 100 ppm to 5,000 ppm based on the total amount of the recording liquid.
pm is preferred, but especially 500 ppm to 1500
It is preferable to use ppm for storage stability. As the carbon black used as a pigment in the recording liquid of the present invention, a commercially available general substance can be used. Its primary particle diameter is 10 to 100 nm and DBP oil absorption is 40 to 150 m.
1/100 g, pH 3 to 9 are good, and primary particle size is 1
0-50 nm, DBP oil absorption 50-130 ml / 100
g is particularly preferred. Specifically, products # 10, # 30, # 33, # 40, # 42, and # 4 manufactured by Mitsubishi Chemical Corporation
5, # 48, # 52, # 95, # 2600, MA7, M
A8, MA11, MA100, MA230, MA600
And the like.

[0008] As the pigment other than carbon black, commercially available pigments can be used. Specifically, Pigment Yellow, Pigment Red, Pigment Violet,
Pigments such as Pigment Blue and Pigment Black can be mentioned, and in addition, pigments such as phthalocyanine, azo, anthraquinone, azomethine, and condensed ring can also be used. In addition, yellow No. 4, No. 5, No. 20
No. 5, 401, Orange No. 204, Red No. 104, 201
No. 202, 204, 220, 226-228
In addition to organic pigments such as No. 405, Blue No. 1 and No. 404, inorganic pigments such as titanium oxide, zinc oxide, zirconium oxide, iron oxide, ultramarine, navy blue and chrome oxide can also be used. These pigments such as carbon black may be used in combination of two or more.

In the recording liquid of the present invention, it is preferable to use a dispersant in addition to the above components. Examples of the dispersant include various anionic surfactants, nonionic surfactants, cationic surfactants, amphoteric surfactants, and polymeric dispersants. Examples of anionic surfactants include fatty acid salts, alkyl sulfate salts, alkyl benzene sulfonates, alkyl naphthalene sulfonates, alkyl sulfosuccinates, alkyl diphenyl ether disulfonates, alkyl phosphates, and polyoxyethylene alkyl sulfates. And polyoxyethylene alkylaryl sulfates, alkane sulfonates, naphthalene sulfonic acid formalin condensates, polyoxyethylene alkyl phosphates, α-olefin sulfonates and the like. Non-ionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene alkyl aryl ethers, polyoxyethylene derivatives, oxyethylene, oxypropylene block copolymers, sorbitan fatty acid esters, polyoxyethylene sorbitan fatty acid esters ,
Examples include polyoxyethylene sorbitol fatty acid esters, glycerin fatty acid esters, polyoxyethylene fatty acid esters, and polyoxyethylene alkylamines. Examples of the cationic surfactant and the amphoteric surfactant include alkylamine salts, quaternary ammonium salts, alkylbetaines, and aminooxides. Examples of the polymer dispersant include polyacrylic acid, styrene / acrylic acid copolymer, styrene / acrylic acid /
Acrylic ester copolymer, styrene / maleic acid copolymer, styrene / maleic acid / acrylic ester copolymer, styrene / methacrylic acid copolymer, styrene /
Examples include methacrylic acid / acrylic acid ester copolymer, styrene / maleic acid half ester copolymer, vinyl naphthalene / maleic acid copolymer, vinyl naphthalene / acrylic acid copolymer, and salts thereof. These internal anionic surfactants, nonionic surfactants and polymer dispersants are particularly excellent.

The aqueous medium used for the recording liquid of the present invention is mainly composed of water, but it is preferable to use a water-soluble organic solvent added to water. Examples of the water-soluble organic solvent include ethylene glycol, propylene glycol, butylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol (# 200, # 400), glycerin, alkyl ethers of the above glycols, N-methylpyrrolidone, 1,3- Dimethyl imidazolinone, thiodiglycol, 2-pyrrolidone, sulfolane, dimethyl sulfoxide, diethanolamine, triethanolamine, ethanol, isopropanol and the like.

[0011] In addition to the above components, the recording liquid of the present invention contains a surfactant, a water-soluble resin, a fungicide, a bactericide, a pH adjuster,
Urea and the like may be added as needed. The method of preparing the recording liquid of the present invention is carried out by mixing the above-mentioned components, grinding the carbon black into fine particles using a disperser, and subjecting the fine particles to a dispersion treatment. As the disperser, a ball mill, a roll mill, a sand grind mill or the like is used, and a sand grind mill is particularly preferable. After grinding and dispersion, coarse particles are removed using a filter or a centrifuge.
It is desirable that the particle size of the carbon black be adjusted to 1 μm or less. Components other than carbon black, a dispersant, and water may be added after grinding and dispersion treatment. In addition, since the grinding and dispersion treatment can be efficiently performed by preparing a high concentration, it is preferable to finally dilute the processing solution prepared at a high concentration with an aqueous medium to adjust the concentration of the recording liquid.

The pigment is used in an amount of 1 to 10% by weight, preferably 2 to 8% by weight, based on the recording liquid. The dispersant is usually used in the range of 5 to 100% by weight based on the pigment.
~ 30% by weight is preferred. The amount of the water-soluble organic solvent used in the recording liquid is usually in the range of 5 to 30% by weight,
% By weight is preferred. The amount of the aqueous medium used is usually 50 to 90% by weight based on the recording liquid.

The pH of the recording liquid is usually 3 to 11, but 6 to 9 is preferable for preserving the recording liquid. One type of these pigments, dispersants, organic solvents and fungicides may be used alone. However, in some cases, more effects can be obtained by using two or more types in combination.

[0014]

EXAMPLES The present invention will be described in more detail with reference to the following Examples, but it should not be construed that the present invention is limited thereto. In the following examples, “parts” means “parts by weight” unless otherwise specified. Example 1 (Preparation of recording liquid) Composition of recording liquid Amount used (parts) Glycerin 16 Ethylene glycol 18 Carbon black MA100 11 (trade name, manufactured by Mitsubishi Chemical Corporation; particle diameter: 22 nm, specific surface area: 134 m 2 / g, DBP oil absorption) 100 ml / 100 g, pH 3.5) Lipolane PB-800 3 (α-olefinsulfonic acid; trade name, manufactured by Lion Corporation) Ion-exchanged water 52５２ １００ Total 100 Put each of the above components in a stainless steel container, average 0.5
Grinding was performed for 60 hours using a sand grinder together with 152 parts of glass beads having a diameter of mm. Ion exchange water 1
26.5 parts and clean side 275 (main component: glutaraldehyde, product of K-I Kasei Co., Ltd.)
After diluting and stirring the obtained solution with a solution obtained by mixing 5 parts,
o. Pressure filtration was performed using a 5C filter paper, and the liquid obtained here was used as a recording liquid. The concentration of glutaraldehyde in the recording liquid was 1100 ppm. (Test for antifungal and antibacterial properties) The recording liquid obtained by the method described in the above example was allowed to stand at 50 ° C and a relative humidity of 30% for one month. At this time, the generation of microorganisms such as molds and fungi was visually evaluated.
The results were classified as follows and are shown in Table 1 below.

○ ────No generation of microorganisms such as molds and fungi was confirmed. Δ──── Microorganisms such as molds and fungi were generated. (Printing Ejection Test) Using a recording liquid obtained by the method described in the above example, an inkjet printer (trade name DeskJet 12 manufactured by Hewlett-Packard) was used.
00C) and electrophotographic paper (Xerox 4024 paper, X
inkjet product). The results were classified as follows and are shown in Table 1 below.

○ ────Stable and good dischargeability without clogging. △ ──── There is a slight dot missing in the printed matter, but there is no practical problem. × ────Dot missing of printed matter is severe. (Water Resistance Test) The printed matter obtained in the printing test was immersed in tap water taken in a beaker for 5 seconds. After the printed matter was dried, the presence or absence of character stain was visually evaluated. The results were classified as follows and are shown in Table 1.

──── There is almost no dirt on the character. △ ──── There is a slight character stain, but there is no practical problem. × ────Dirty. (Light fastness test) The printed matter was irradiated with a xenon fade meter (manufactured by Suga Test Instruments Co., Ltd.) for 100 hours, and the discoloration and discoloration were visually evaluated. The results were classified as follows and are shown in Table 1.

○ ──── Good. △ ──── There is discoloration but no practical problem. × ──── Discoloration and discoloration are severe. (Storage stability test of recording liquid) The recording liquid was sealed in a Teflon container and stored at 60 ° C for one month. The presence or absence of gelation or precipitate was visually evaluated. The results were classified as follows and are shown in Table 1.

○ ──── Almost no gelation or precipitate. △ ──── Slightly gelled or precipitated, but no practical problem. × ──── Gelation and precipitates are severe. Example 2 (Preparation of recording liquid) Composition of recording liquid Used amount (parts) Glycerin 16 Ethylene glycol 18 Carbon black MA8 11 (trade name, manufactured by Mitsubishi Chemical Corporation; particle diameter 24 nm, specific surface area 137 m 2 / g, DBP oil absorption) 58 ml / 100 g, pH 3.0) Polystar S2-1020 (non-volatile content) 3 (styrene / maleic anhydride copolymer; trade name, manufactured by NOF CORPORATION) Ion-exchanged water 52 １００ Total 100 Put each of the above components in a stainless steel container, average 0.5
Grinding was performed for 60 hours using a sand grinder together with 152 parts of glass beads having a diameter of mm. Ion exchange water 1
26.5 parts and clean side 275 (main component: glutaraldehyde, product of K-I Kasei Co., Ltd.)
After diluting and stirring the obtained solution with a solution obtained by mixing 5 parts,
o. Pressure filtration was performed using a 5C filter paper, and the liquid obtained here was used as a recording liquid. The concentration of glutaraldehyde in the recording liquid was 1100 ppm.

Print ejection test, water resistance test, light resistance test,
The storage stability test, the antifungal / bactericidal test and the evaluation were performed in the same manner as in Example 1. Table 1 shows the evaluation results. Example 3 (Preparation of recording liquid) Composition of recording liquid Amount used (parts) Glycerin 16 Ethylene glycol 18 Carbon black MA230 11 (trade name, manufactured by Mitsubishi Chemical Corporation; particle diameter: 24 nm, specific surface area: 137 m 2 / g, DBP oil absorption) 58 ml / 100 g, pH 3.0) Penelol NP-50 (polyoxyethylene 2 alkylaryl ether; trade name of Matsumoto Yushi Co., Ltd.) Ion-exchanged water 53 １００ Total 100 Put each of the above components in a stainless steel container, average 0.5
Grinding was performed for 60 hours using a sand grinder together with 152 parts of glass beads having a diameter of mm. Ion exchange water 1
26.5 parts and clean side 275 (main component: glutaraldehyde, product of K-I Kasei Co., Ltd.)
After diluting and stirring the obtained solution with a solution obtained by mixing 5 parts,
o. Pressure filtration was performed using a 5C filter paper, and the liquid obtained here was used as a recording liquid. The concentration of glutaraldehyde in the recording liquid was 1100 ppm.

Printing discharge test, water resistance test, light resistance test,
The storage stability test, the antifungal / bactericidal test and the evaluation were performed in the same manner as in Example 1. Table 1 shows the evaluation results. Example 4 (Preparation of recording liquid) Composition of recording liquid Amount (parts) Glycerin 16 Ethylene glycol 18 Carbon black # 10 11 (trade name, manufactured by Mitsubishi Chemical Corporation; particle diameter: 84 nm, specific surface area: 28 m 2 / g, DBP oil absorption) 86 ml / 100 g, pH 7.0) POLYSTAR S2-1020 (non-volatile) 1 (styrene / maleic anhydride copolymer; trade name, manufactured by NOF CORPORATION) Ion-exchanged water 54 １００ Total 100 Put each of the above components in a stainless steel container, average 0.5
Grinding was performed for 60 hours using a sand grinder together with 152 parts of glass beads having a diameter of mm. Ion exchange water 1
26.5 parts and clean side 275 (main component: glutaraldehyde, product of K-I Kasei Co., Ltd.)
After diluting and stirring the obtained solution with a solution obtained by mixing 5 parts,
o. Pressure filtration was performed using a 5C filter paper, and the liquid obtained here was used as a recording liquid. The concentration of glutaraldehyde in the recording liquid was 1100 ppm.

Print ejection test, water resistance test, light resistance test,
The storage stability test, the antifungal / bactericidal test and the evaluation were performed in the same manner as in Example 1. Table 1 shows the evaluation results. Example 5 (Preparation of recording liquid) Composition of recording liquid Amount used (parts) Glycerin 16 Ethylene glycol 18 Carbon black MA220 11 (trade name, manufactured by Mitsubishi Chemical Corporation; particle diameter 55 nm, specific surface area 31 m 2 / g, DBP oil absorption) 91 ml / 100 g, pH 3.0) Lipolane PB-800 1 (α-olefinsulfonic acid; trade name, manufactured by Lion Corporation) Ion-exchanged water 54 １００ Total 100 Put each of the above components in a stainless steel container, average 0.5
Grinding was performed for 60 hours using a sand grinder together with 152 parts of glass beads having a diameter of mm. Ion exchange water 1
26.5 parts and clean side 275 (main component: glutaraldehyde, product of K-I Kasei Co., Ltd.)
After diluting and stirring the obtained solution with a solution obtained by mixing 5 parts,
o. Pressure filtration was performed using a 5C filter paper, and the liquid obtained here was used as a recording liquid. The concentration of glutaraldehyde in the recording liquid was 1100 ppm.

Printing discharge test, water resistance test, light resistance test,
The storage stability test, the antifungal / bactericidal test and the evaluation were performed in the same manner as in Example 1. Table 1 shows the evaluation results. Example 6 (Preparation of recording liquid) Composition of recording liquid Used amount (parts) Glycerin 16 Ethylene glycol 18 C.I. I. Pigment Yellow-74 11 Polystar S2-1020 (non-volatile content) 3 Deionized water 52 合計 Total 100 Put each of the above components in a stainless steel container,
Grinding was performed for 60 hours using a sand grinder together with 152 parts of glass beads having a diameter of mm. Ion exchange water 1
26.5 parts and clean side 275 (main component: glutaraldehyde, product of K-I Kasei Co., Ltd.)
After diluting and stirring the obtained solution with a solution obtained by mixing 5 parts,
o. Pressure filtration was performed using a 5C filter paper, and the liquid obtained here was used as a recording liquid. The concentration of glutaraldehyde in the recording liquid was 1100 ppm.

Print ejection test, water resistance test, light resistance test,
The storage stability test, the antifungal / bactericidal test and the evaluation were performed in the same manner as in Example 1. Table 1 shows the evaluation results. Example 7 (Preparation of recording liquid) Composition of recording liquid Amount used (parts) Glycerin 16 Ethylene glycol 18 C.I. I. Pigment Blue-15 11 Lipolan PB-800 3 Deionized water 52 ─────────────────────────────── Total 100 Each of the above Take the ingredients in a stainless steel container and average 0.5
Grinding was performed for 60 hours using a sand grinder together with 152 parts of glass beads having a diameter of mm. Ion exchange water 1
26.5 parts and clean side 275 (main component: glutaraldehyde, product of K-I Kasei Co., Ltd.)
After diluting and stirring the obtained solution with a solution obtained by mixing 5 parts,
o. Pressure filtration was performed using a 5C filter paper, and the liquid obtained here was used as a recording liquid. The concentration of glutaraldehyde in the recording liquid was 1100 ppm.

Print ejection test, water resistance test, light resistance test,
The storage stability test, the antifungal / bactericidal test and the evaluation were performed in the same manner as in Example 1. Table 1 shows the evaluation results. Example 8 (Preparation of recording liquid) Composition of recording liquid Amount used (parts) Glycerin 16 Ethylene glycol 18 C.I. I. Pigment Red-122 11 DKS-Discoat N-14 3 (brand name of anionic dispersant, brand name of Daiichi Kogyo Seiyaku Co., Ltd.) １００ Total 100 Put each of the above components in a stainless steel container, average 0.5
Grinding was performed for 60 hours using a sand grinder together with 152 parts of glass beads having a diameter of mm. Ion exchange water 1
26.5 parts and clean side 275 (main component: glutaraldehyde, product of K-I Kasei Co., Ltd.)
After diluting and stirring the obtained solution with a solution obtained by mixing 5 parts,
o. Pressure filtration was performed using a 5C filter paper, and the liquid obtained here was used as a recording liquid. The concentration of glutaraldehyde in the recording liquid was 1100 ppm.

Print ejection test, water resistance test, light resistance test,
The storage stability test, the antifungal / bactericidal test and the evaluation were performed in the same manner as in Example 1. Table 1 shows the evaluation results.

[0027]

[Table 1]

[0028]

The recording liquid for ink-jet recording of the present invention has good storage stability. By using this recording liquid, it is possible to perform recording with good dischargeability and high reliability, and even when recording on plain paper. It is possible to obtain a recorded matter having good water fastness and good fastness other than water fastness such as print quality and light fastness. Since the present invention has the above characteristics, it can be used as a recording liquid for other purposes, not limited to ink jet and writing instruments.

Claims (2)

[Claims] 1. A recording liquid comprising an aqueous medium, a pigment and glutaraldehyde. 2. The recording liquid according to claim 1, wherein carbon black is contained as a pigment.