JPH01193375A - Recording liquid - Google Patents

Abstract

PURPOSE:To obtain a novel black recording liquid capable of satisfying characteristics, such as water and light resistance, fixing properties after printing, safety and preservation stability, and carrying out recording of excellent printing quality on ordinary paper, by using a specific dye as a recording agent. CONSTITUTION:A recording liquid obtained by dissolving or dispersing a dye expressed by formula I [Q1-Q3 are (substituted) benzene or naphthalene ring; Q4 is formula II (R1-R4 are H, OH, etc.) or formula III; M is base, such as Na or K; m is 0 or 1] and/or formula IV [Q1 and Q2 are (substituted) benzene or naphthalene ring; Q3 is H or (substituted) benzene ring] used as a recording agent in a solvent substance. Furthermore, the amount of the recording agent expressed by formulas and/or IV is preferably 1-10wt.% based on the total amount of the recording liquid. Water or a mixture thereof with an organic solvent, such as alcohol or ether, is preferably used as the above-mentioned solvent substance.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention provides a new recording liquid, particularly a recording liquid for writing (fountain pens, felt pens, etc.). The present invention relates to a recording liquid suitable for the so-called 6-inkjet recording method in which recording is performed by ejecting the liquid from an orifice and flying it as droplets.

(Prior Art) The inkjet recording method is a method of recording by causing droplets of a recording liquid called ink to fly and adhering to a recording material. The basic components of such a recording liquid include a recording agent (dye or pigment is used) and a liquid medium for dissolving or dispersing it (water, various organic solvents, acids, or mixtures thereof are used), and the necessary Depending on the situation, various additives are added. The desirable characteristics of the recording liquid are (1) that the printed image has excellent water resistance and light resistance, (2) that it fixes quickly on the recording material and that the periphery of the dots is smooth. Small bleeding; in particular, when printing on so-called plain paper that does not have a coating layer on the surface, dot shapes should not be irregularly disturbed (so-called feathering) due to uneven penetration speed of the recording liquid; (3) The color tone of the printed image is clear and has a high density; (4) If it is compatible with an inkjet method that ejects recording liquid by the action of thermal energy, no deposits should be formed on the heater; (5) It has liquid physical properties (viscosity, surface tension, electrical conductivity, etc.) that match the discharge conditions (piezoelectric element drive voltage, drive frequency, orifice shape and material, orifice diameter, etc.); (6) (7) The recording liquid should not corrode surrounding materials (containers, connecting tubes, sealing materials, etc.); (8) It should be stable in terms of odor, toxicity, flammability, etc. for long-term storage; One example is that it has excellent safety.

Among these performance requirements, the points that are particularly technically difficult are as described above (
+), (2), (:]) and (4) at the same time.

Further, since the recording liquid used for recording for such purposes is basically composed of a recording agent and its solvent, the above-mentioned characteristics of the recording liquid are largely influenced by the properties specific to the recording agent. Therefore, selecting a recording agent so that the recording liquid has the above characteristics is an extremely important technique in this technical field.

For example, recording liquids using conventionally known black dyes, such as Food Black 2 and Nigrosine (Acid Black 2), had insufficient properties such as water resistance, post-print fixability, density, and bleeding. .

(Problems to be Solved by the Invention) Therefore, an object of the present invention is to provide a black recording liquid that satisfies the above-mentioned characteristics and is capable of recording good print quality, especially on plain paper. It is.

(Means for solving problems) The above objects are achieved by the present invention as described below.

That is, the present invention provides a recording liquid containing a recording agent, which is a component for forming a recorded image, and a liquid medium for dissolving or dispersing this recording agent. This liquid is characterized by containing at least one of the dyes shown below.

However, Ql, Q2 and Q3 in the formula represent a substituted or unsubstituted Nohensen ring or naphthalene ring, Q4Rl, R2,
Rs and R4 each independently represent a hydrogen atom, a hydroxyalkyl group, or an acetyl group, and M represents sodium, potassium,
It represents one base derived from lithium, ammonium, and amines, and m is 0 or 1.

However, Ql and Q2 in the formula represent a substituted or unsubstituted Hensen ring or a naphthalene ring, Q3 represents a substituted or unsubstituted Hensen ring or a hydrogen atom, and Q4. M and m are Q4 in general formula (1). Type the same meanings as M and m.

(Preferred Embodiments) Next, the present invention will be described in more detail by citing preferred embodiments.

The dye represented by the above general formula (1) or (2) that is used in the present invention and mainly characterizes the present invention may be any dye as long as it is included in the above general formula (1) or (2). However, particularly preferred specific examples include:
For example, the following can be mentioned.

The recording liquid of the present invention contains the above dye and a liquid medium for dissolving or dispersing the dye, and the liquid medium used is water or a mixture of water and various 41 organic solvents.

Examples of water-soluble organic solvents used in combination with water include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, 5ec-butyl alcohol, lert-butyl alcohol, and isobutyl alcohol. Alkyl alcohols having 1 to 4 carbon atoms; Amides such as dimethylformamide and dimethylacetamide; Ketones or ketone alcohols such as acetone and diacetone alcohol; Ethers such as tetrahydrofuran and dioxane; N-methyl-2-pyrrolidone, 1 .3-Dimethyl-2-imidazolidinone and other nitrogen-containing heterocyclic % formula% polyalkylene glycols such as glycol; ethylene glycol, propylene glycol, butylene gelicol, triethylene glycol, 1.2.6-hexane Alkylene glycols containing an alkylene group or 2 to 6 carbon atoms such as doliol, thiodiglycol, hexylene glycol, diethylene glycol; glycerin; ethylene glycol methyl (or ethyl) ether;
diethylene glycol methyl (or ethyl) ether,
Examples include lower alkyl ethers of polyhydric alcohols such as triethylene glycol monomethyl (or ethyl) needle.

When a mixture of water and the above-mentioned water-soluble organic solvent is used as a liquid medium component, the content of the above-mentioned water-soluble organic solvent is generally 5 to 95% by weight based on the total ffi amount of the recording liquid.
%, preferably in the range of 10 to 80%, more preferably in the range of 20 to 50%.

Further, the general formula (1) and/or the general formula (1) dissolved in the liquid medium may be dissolved in the liquid medium.
The amount of the dye (2) is generally about 0.1 to 20% by weight, preferably 0.5 to 15% by weight in the total amount of the recording liquid.
%, more preferably 1 to 10%.

Of course, the dyes represented by the general formulas (1) and/or (2) can be used alone or as a mixture, and can also be used in combination with other recording agents as long as the object of the present invention is not hindered.

The recording liquid of the present invention prepared from such components can itself improve the water resistance, light resistance, bleeding characteristics, fixing properties of recorded images, and recording characteristics (signal response, stability of droplet formation) of recorded images. sex,
It is well-balanced and excellent in terms of ejection stability, long-term continuous recording performance, ejection stability after long-term recording cessation), and storage stability.

In order to further improve such properties, various conventionally known additives may be added.

For example, viscosity modifiers such as polyvinyl alcohol, cellulose, and water-soluble resins; various cationic, anionic, or nonionic surfactants; surface tension modifiers such as jetanolamine and triethanolamine; PH modifiers using buffer solutions; Antifungal agents and the like can be mentioned.

In addition, in order to prepare the recording liquid used in the type of inkjet recording method that charges the recording liquid, lithium chloride,
A resistivity adjuster such as inorganic salts such as ammonium chloride and sodium chloride is added.

When applied to an inkjet recording method in which recording liquid is ejected by the action of thermal energy, thermal physical property values (e.g., specific heat, coefficient of thermal expansion, thermal conductivity, etc.)
(Function/Effect) Inkjet recording liquid is mainly used for safety reasons, and is made by dissolving or dispersing recording agents such as dyes or pigments in a liquid medium mainly composed of water. Typically, a low-volatility water-soluble organic solvent such as glycol is added as a wetting agent. Therefore, various properties of the recording liquid, especially the water resistance of printed matter, bleeding of recorded images, fixing properties, etc., are largely influenced by the properties specific to the recording agent.

The dye used in the present invention has extremely high affinity for paper and other recording materials, and therefore has excellent fixability to recording materials.
The water resistance of printed matter and the bleeding resistance of recorded images are excellent.

Therefore, the recording liquid of the present invention containing such a dye can be applied not only to specially developed recording materials called inkjet recording paper, but also to commonly used copy paper, report paper, pound paper, etc. slip paper, continuous slip paper,
Since the recording liquid of the present invention can be fully used as a recording liquid for papers widely used in households and offices, such as high-size paper, low-size paper, and plain paper, the recording liquid of the present invention will further accelerate the spread of inkjet recording methods. It is possible to do so.

Furthermore, since the recording liquid of the present invention sufficiently exhibits the above-mentioned effects even when its pH is around neutral, it is
It does not require the addition of a strong alkaline substance as described in Publication No. 2, is preferable in terms of safety, and is suitable for use in general homes and offices.

Furthermore, even when the recording liquid of the present invention is applied to an inkjet system in which the recording liquid is ejected by the action of thermal energy, no deposits are generated on the heater. In addition, physical property values such as viscosity and surface tension are within appropriate ranges,
The fine discharge orifice does not become clogged, provides a recorded image of sufficiently high density, and does not cause changes in physical properties or precipitation of solid content during storage.

Further, the recording liquid of the present invention is not only excellent as a recording liquid for the above-mentioned ink sheet recording, but also can be used as a recording liquid for writing instruments.

Next, the present invention will be explained in more detail with reference to Examples, Comparative Examples, and Usage Examples. In the text, parts or percentages are based on weight unless otherwise specified.

Example 1 Ion exchange water (hereinafter abbreviated as water) 71 parts diethylene glycol 25 parts Dye of Example 1
4 parts The above components were thoroughly mixed and dissolved in a container, filtered under pressure through a Teflon filter with a pore size of 1 μm, and then degassed using a vacuum pump to obtain a recording liquid of the present invention.

Example 2 Water 77 parts Diethylene glycol 15 parts N-methyl-2-pyrrolidone 5 parts Dye of Example 2
3 parts Each of the above components was treated in the same manner as in Example 1 to obtain a recording liquid of the present invention.

Example 3 Water 75 parts Glycerin 5 parts Diethylene glycol 15 parts Dye of Example 6
5 parts Each of the above components was treated in the same manner as in Example 1 to obtain Katsuaki Moto's recording liquid.

Comparative Example 1 Water, 71 parts Diethylene glycol 25 parts C, R, Acid Black 2 4 parts The above components were treated in the same manner as in Example 1 to obtain a recording liquid of a comparative example.

Comparative Example 2 Water 77 parts Diethylene glycol 15 parts N-methyl-2-pyrrolidone 5 parts, 1. Food Black 2 3 parts Each of the above components was treated in the same manner as in Example 1 to obtain a recording liquid of a comparative example.

Usage example: An inkjet printer using the recording liquids of the above-mentioned Example B'a and Comparative Example and using a heating element as an energy source for ejecting the recording liquid as an inkjet recording device (orifice size 40 x 50 μm, heater size 50 x
150μm, number of nozzles: 24).
It was printed on the paper shown in the table, and the following evaluation (i) was performed (jf value results are shown in Table 2 below).

1-1 (T1) Long-term storage stability of the recording liquid: After sealing the recording liquid in a glass container and storing it at -30°C and 60°C for 3 months, the precipitation of insoluble matter and the liquid The characteristics and color tone were observed.

(T2) Discharge stability: Continuous discharge was performed for 24 hours in an atmosphere of 5° C., room temperature, and 40° C., respectively.

(1) Ejection responsiveness: Intermittent ejection for 2 seconds and ejection after being left for 2 months were performed.

(T4) Recorded image quality: Recorded image under room light
The rate of decrease in concentration after rubbing for a month was measured. In addition, it was immersed in water for 1 hour to determine the change in density at t111, and the printed area was traced using a Pilot ■ spot writer (pink) to observe the degree of dyeing of the printed area.

(T,) Occurrence rate of bleeding: Regarding the incidence of bleeding,
300 dots were printed on the front paper using a printer in a non-consecutive manner (printed at 20±5℃, 50±10% R11)
After that, it was left to stand for more than 1 hour, and then the number of dots in which bleeding occurred was counted using a microscope, and the percentage of bleeding was determined and an IIF value was determined.

γ]1-P-mi -La1P11　　　　　　Me, power.

Canon Nil paper copy 11 paper
Canon Xerox Corporation 4024DP
Copy paper Xerox Co., Ltd. 87-Milpont' Bond paper Hen7-
However, the name of the recording material in Table 1 above is the product name.

Example 200 0 0 0 Example 3 00000 Comparative Example 1 × ○ ××× Comparative Example 2 0 0 0 × △ T, :○: No precipitation of insoluble matter, no change in liquid characteristics or color tone was observed.

A trace amount of precipitate was observed at the bottom of the storage bottle at ×=60°C.

T2: ○=stable discharge T, 20=stable discharge without clogging×=clogging occurred after being left for 2 months and discharging became impossible.

T, :Q=3 All performances are good.×=Light resistance is good, and water resistance shows that image density becomes 30% or less after being left in water for 1 hour, and stains due to marker rubbing are severe.

T5:○=10% or less △=11~5130% ×=31% or more

Claims (2)

[Claims] (1) In a recording liquid containing a recording agent that is a component for forming a recorded image and a liquid medium for dissolving or dispersing this recording agent, the recording agent is represented by the following general formula (1) or (2). A recording liquid characterized by containing at least one kind of dye. ▲There are mathematical formulas, chemical formulas, tables, etc.▼(1) (However, Q_1, Q_2 and Q_3 in the formula represent substituted or unsubstituted benzene rings or naphthalene rings, and Q_4 is ▲
There are mathematical formulas, chemical formulas, tables, etc. ▼ or ▲ mathematical formulas, chemical formulas,
There are tables, etc. ▼, R_1, R_2, R_3 and R_4 each independently represent a hydrogen atom, a hydroxyalkyl group, an acetyl group, and M is 1 selected from sodium, potassium, lithium, ammonium and amines. bases, m is 0 or 1
It is. ) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(2) (However, Q_1 and Q_2 in the formula represent a substituted or unsubstituted benzene ring or naphthalene ring, and Q_3 represents a substituted or unsubstituted benzene ring or a hydrogen atom. and Q_4, M and m have the same meanings as Q_4, M and m in general formula (1).) (2) The record according to claim (1), wherein the dye represented by formula (1) and/or (2) is contained in an amount of 0.1 to 20% by weight based on the total weight of the recording liquid. liquid.