JPS60243174A - Recording solution - Google Patents

Abstract

PURPOSE:A recording solution that contains, as a recording agent, a specific dye, thus being suitable for use in ink-jet recording, because it causes no clogging in the recording means, no changes in physical properties and no precipitation of solids during storage. CONSTITUTION:The objective recording solution contains a recording agent as a major component and a medium containing at least water and glycol for dissolving or dispersing the recording agent where at least one of dyes of the formula [M is Na, Li, K or amine and one or two among 4 Ms is NH3CH2CH2OH, NH2(CH2CH2OH)2 or NH(CH2CH2OH)3].

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a novel recording liquid used for ink recording, and particularly to a recording liquid that does not cause clogging in recording means and is particularly suitable for inkjet recording.

[Prior art]

Traditionally, writing instruments (fountain pens, felt-tip pens, etc.) used as recording means to record on recording materials such as paper have been made using (recording liquid).
As inks, various dyes dissolved in water or organic solvents are used.

Furthermore, in the so-called inkjet recording method, in which recording is performed by ejecting liquid in the recording head from an ejection orifice using vibrations caused by a piezo vibrator or electrostatic attraction caused by the application of high voltage, various dyes are applied to wood or organic solvents. It is known to use compositions dissolved in, etc. However, compared to inks for general stationery such as fountain pens and felt-tip pens, inkjet recording liquids are required to meet -1 more stringent conditions in many characteristics.

In such an inkjet recording method, recording is performed by flying droplets of a recording liquid called ink and adhering them 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, or mixtures thereof are used), and various additives are added as necessary. agent is added.

Conventionally, as this type of recording liquid, for example, Japanese Patent Publication No. 50-83
No. 81, Special Publication No. 5+-40484, Special Publication No. 52-13
No. 128, JP 52-13127, JP 50-9
As shown in No. 5008, dyes or pigments in which various dyes or pigments are dissolved or dispersed in aqueous or non-aqueous solvents are known.

Preferred conditions for this type of recording liquid include: 1) liquid physical properties (viscosity, surface tension, conductivity, etc.) that match the ejection conditions (piezoelectric element drive voltage, drive frequency, orifice shape and material, orifice diameter, etc.); have.

2) Stable and free from clogging during long-term storage.

3) Fixation is fast on the recording material (paper, film, etc.), and the dot periphery is smooth and there is little bleeding.

4) The color tone of the printed image is clear and the density is high.

5) The printed image has excellent water resistance and light resistance.

6) The recording liquid should not corrode surrounding materials (containers, connecting tubes, sealing materials, etc.).

7) It must be safe in terms of odor, toxicity, and flammability.

etc.

It is quite difficult to simultaneously satisfy the above characteristics, and the prior art described above was unsatisfactory in this respect.

Since the recording liquid used for recording for such purposes is basically composed of a dye and its solvent as described above, the characteristics of the recording liquid described above depend on the characteristics of the dye and the components used as the liquid medium. Much depends on the nature of. Therefore, selecting a dye and a liquid medium so that the recording liquid has the above-mentioned properties is an extremely important technique in this technical field.

In particular, with regard to recording liquids using yellow dyes, there is still no known recording liquid that fully satisfies all of the above-mentioned characteristics.

Conventionally, water or a mixture of water and various water-soluble organic solvents has been used as the liquid medium for the recording liquid. A mixture of water and a glycol such as ethylene glycol or diethylene glycol has been used more preferably than water alone.

On the other hand, dyes for yellow recording liquids are generally C,1,
Yellow dyes typified by Direct Yellow 86 have conventionally been used.

However, these dyes are soluble in water.

Although it has excellent fixability to recording materials, safety, etc., in order to more strictly satisfy the characteristics of the recording liquid in general, the above-mentioned mixture of water and glycols is used as a liquid medium. When used as yellow dyes, the solubility in the liquid medium is insufficient, and recording liquids using these yellow dyes are
In particular, stability and long-term storage stability are often not always sufficient, and there is a problem in that the recording liquid discharge port of the recording means is easily clogged.

As a result of extensive research, the present invention was completed by finding a dye suitable for the recording liquid used for this purpose.

That is, the recording liquid of the present invention includes a recording agent which is a component forming the recording liquid, and a liquid medium containing at least water and glycols for dissolving or dispersing the recording agent. , the following general formula (A) as a recording agent;
or one M is a base selected from amines represented by NH2OH2CHzOHl NH2(C)hcH20Hh and N)l (CH2G!(20H) 3 ).
It is characterized by containing at least one type of dye represented by:

Specific examples of the dye represented by the general formula (A) to be applied to the recording liquid of the present invention include those having the structures shown in Table 1 as used in the following examples.

These dyes exhibit superior performance in meeting the various required properties as compared to conventionally known dyes having similar structures. For example, the dye represented by the general formula (A) has excellent solubility especially in glycols used as a solvent component of the recording liquid, compared to the dye represented by the following structural formula (1). .

This good solubility in glycols is due to the above formula (1)
This is because two or one of the -5O3Na groups in is substituted with a base selected from the amines shown above.

The dye represented by the general formula (A), that is, the diazo compound applied to the recording liquid of the present invention, has the following structural formula (
2) Two or one Ml of the four M's in the above formula of the dye represented by [wherein Ml represents any one of Ha, Li, K (1)], NH2OH2CHzOHl NH2(CH2CH20M )2 and NH(CHzCH20H)3 by substitution with a base selected from amines.

Such a method includes, for example, converting four 1503M1 groups of the dye represented by the general formula (2) into 18o3H groups by a method such as acid precipitation, and then converting one of these four groups to 18o3H groups. Each of the two or three hydrogens is replaced with Na,
Substituted with Li or K, that is, treated with a predetermined amount of an aqueous solution of Na1l, KCI, LiCl, etc. in order so that two or one of the four M's remains as -5O3) group, and further , is produced by adding an excess of one or more selected from the above amines to this, and replacing the hydrogen of two or one -503H group with a base selected from the above amines. method can be applied.

The recording liquid of the present invention has the above general formula (
As a liquid medium for dissolving or dispersing one or more dyes represented by A), a liquid medium containing at least water and glycols and particularly effective in preventing clogging is used.

Glycols that can be used include polyalkylene glycols such as polyethylene glycol and polypropylene glycol; ethylene glycol, propylene glycol,
Butylene gelicol, triethylene glycol, 1,2
．． Alkylene glycols in which the alkylene group contains 2 to 6 carbon atoms, such as 6-hexandriol, thiodiglycol, hexylene glycol, diethylene glycol; glycerin; ethylene glycol methyl ether, diethylene glycol methyl (or ethyl) ether;
Examples include lower alkyl ethers of polyhydric alcohols such as triethylene glycol monomethyl (or ethyl) ether, and one or more of these can be used as the liquid medium component.

The content of the glycols in the recording liquid is generally 10 to 70% by weight, preferably 2% by weight based on the total weight of the recording liquid.
The range is 0 to 60%, more preferably 25 to 50%.

In the recording liquid of the present invention, in addition to 1-glycols as liquid medium components, water-soluble organic solvents such as methyl alcohol, ethyl alcohol, n- Alkyl alcohols having 1 to 4 carbon atoms such as propyl alcohol, isopropyl alcohol, n-butyl alcohol, 5ec-butyl alcohol, tert-butyl alcohol, isobutyl alcohol;
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,
One or more types of nitrogen-containing heterocyclic ketones such as 3-dimethyl-2-imidazolidinone may be added.

The content of water-soluble organic solvents including glycols in the recording liquid is generally 1% by weight based on the total weight of the recording liquid.
The range is 0 to 70%, preferably 20 to 80%, more preferably 25 to 55%.

The water content at this time depends on the type of solvent component mentioned above.

Although it is determined in a wide range depending on the composition or desired properties of the recording liquid, generally 3
The range is 0 to 80%, preferably 40 to 80%, more preferably 45 to 75%.

The recording liquid of the present invention can be prepared as follows. The color component (recording agent component), that is, the content of the dye represented by the general formula (A) above, is determined depending on the type of liquid medium, the characteristics required of the recording liquid, etc. The content ranges from 0.05 to 10% by weight, preferably from 0.05 to 6%, and more preferably from 0.05 to 4% based on the total weight. Of course, these dyes can be used alone, in combination of two or more, or in combination with other direct dyes or acid dyes.

When a recording liquid prepared from such components is used as a recording liquid for writing instruments such as fountain pens, water-based ballpoint pens, and felt-tip pens, it has poor fixability to recording materials or the light resistance and weather resistance of recorded images. Not only is it well-balanced and excellent in terms of durability and water resistance, but there is no dye precipitation at the recording liquid outlet such as the pen tip after long-term storage, which is the case with conventional recording liquids. It is an excellent recording liquid that does not cause clogging. In addition, even when used for inkjet recording, recording characteristics (signal response, stability of droplet formation,
ejection stability, long-term continuous recording performance, ejection stability after a long period of recording interruption), storage stability, fixation to the recording material, or the light resistance, weather resistance, water resistance, etc. of the recorded image. All of them are well-balanced and have excellent characteristics, especially when compared to the recording liquid containing the dye represented by the formula (1) mentioned above as a recording agent. It has clear advantages in that it is stable and does not cause clogging of the discharge orifice.

In order to further improve such characteristics, the recording liquid of the present invention may further contain various conventionally known additives, such as polyvinyl alcohol, celluloses, water-soluble resins, etc. Viscosity modifiers such as: various cationic, anionic or nonionic surfactants; surface tension modifiers such as jetanolamine and triethanolamine; 1.

Further, in order to prepare a recording liquid used in an inkjet recording method of a type in which the recording liquid is charged, a resistivity adjuster such as an inorganic salt such as lithium chloride, ammonium chloride, or sodium chloride is added.

Note that when applied to an inkjet system in which recording liquid is ejected by the action of thermal energy, thermal physical property values (eg, specific heat, coefficient of thermal expansion, thermal conductivity, etc.) may be adjusted.

According to the present invention, physical property values such as viscosity and surface tension are within appropriate ranges, and the recording liquid ejection openings such as the nib of a fountain pen or the fine orifice of an inkjet recording device are not clogged and are sufficiently It provides recorded images with high density, does not cause changes in physical properties or precipitation of solids during storage, can record on various materials without limiting the type of recording material, has a high fixing speed, and is water resistant. A recording liquid that provides images with excellent light resistance, abrasion resistance, and resolution can be obtained.

The present invention will be explained in more detail with reference to the following examples and reference examples.

Reference Example 1 (Synthesis of dye 6,1) Commercially available dye Kayaku Direct Y represented by the following structural formula
yellow Rspecial (C, 1, Direc
t yellow 8B) (manufactured by Nippon Kayaku Co., Ltd.) 10
8 g was dissolved in 10 m+ of water, treated with a cation exchange resin (Diaion 5K-IB, manufactured by Mitsubishi Kasei Corporation), and concentrated to dryness to obtain 98 g of powder. The Na content of the obtained powder was determined by atomic absorption spectrometry. As a result of the measurement, the Na content was 1100 pp or less.Next, 50g of this powder was added to a 2% by weight NaOH aqueous solution 2
00g, stirred and reacted to convert two of the four -9o3H groups per molecule into -5O3Na groups,
Furthermore, 6.1 g of monoethanolamine was added to this,
Stir and react to convert the remaining two -503H groups into -8
Converted to O3NH3CH2CH20H group.

Finally, the reaction solution was concentrated to 1,001 ml, reprecipitated in 2,001 ml of ethanol, collected by suction filtration, and 52 g of N6.
1 of dye was obtained.

Reference Example 2 (Synthesis of dye of /li, 2) Using 10.5 g of jetanolamine, two remaining -
803H group -5o3N)12(CH2CH20H)z
55 g of dye No. 2 was synthesized in the same manner as in Reference Example 1 except that the dye No. 2 was converted into a base.

Reference Example 3 [Synthesis of dye of Notification 3] Using 15 g of triethanolamine, two residual -8
o3H group -9O3NH (()12C)120H)
58g in the same manner as Reference Example 1 except that it was converted to 3 groups.
A dye of N63 was synthesized.

Reference Example 4 [Synthesis of dye of 々4] 50 g of the precipitate powder was mixed with 20 g of a 3% by weight NaOH aqueous solution.
0 g, stirred and reacted to convert three of the 4-9o3H groups per molecule into -5O3Na groups, and further added 3.05 g of monoethalamine, stirred and reacted. Then, convert the remaining one -9o3H group to -50
48 g of Al1.4 dye was synthesized in the same manner as in Reference Example 1 except that the dye was converted to 3NH3CH2CH2OH group.

Reference Example 5 [Synthesis of N65 dye] 5.25. of jetanolamine to replace the one'' remaining -503H group with -9O3NH2(CH2CH20H)2
51 g of the dye of Step 5 was synthesized in the same manner as in Reference Example 4 except for the conversion to the base.

Reference Example 6 [Synthesis of H6C dye] Using 7.5 g of triethanolamine, one remaining -
3o3H group -503N)I (CH2C820H)3
Dye 53. of Step 6 was prepared in the same manner as in Reference Example 4 except that dye 53. was synthesized.

Example 1 [Liquid medium composition] 60 parts by weight of ion exchange water (hereinafter abbreviated as water) 40 parts by weight of diethylene gelcol A dye of the same composition as a recording agent was added to a liquid medium having the above composition at a concentration of the dye in the recording liquid. was added to a concentration of 3% by weight, thoroughly mixed and dissolved, filtered under pressure through a Teflon filter with a pore diameter of tg, and then degassed using a vacuum pump to obtain a recording liquid.

Using the obtained recording liquid, an on-demand recording head (discharge orifice diameter 50μ, piezoelectric vibrator drive voltage 60V, frequency 4
Inkjet recording was carried out using a recording device having a high frequency (KHz), and the following items, which had been problematic with conventional recording liquids, were particularly investigated. Table 1 shows the results obtained.
Shown below.

(T+) Long-term storage of recording liquid Recording liquid was sealed in a glass container and stored at -30℃ and 60℃ for 6 hours.
After being stored for a month, it was tested and evaluated to see if precipitation of insoluble matter was observed. (0) indicates that no precipitation of insoluble matter was observed; (×) indicates that precipitation of insoluble matter was observed.
And so.

(T2) Discharging stability: Continuous discharging was performed for 24 hours in an atmosphere of room temperature, 5° C., and 40° C., respectively. Under any conditions, a case where stable high-quality recording could be performed from beginning to end was rated as (0), and a case where it could not be recorded was rated as (x). The middle point was defined as (Δ).

(T3) Ejection responsiveness: The recording device was operated after being left for 3 months, and the ejection state in intermittent ejection every 2 seconds before and after being left was examined. If the stable and uniform dispensing condition before being left is also obtained after being left standing (
0), a slight disturbance in the discharge was observed at the beginning of operation after being left unused, but a stable and uniform discharge condition was obtained after a few seconds (O), a case in which a stable and uniform discharge condition was obtained before being left unattended. The case where it was not obtained later was designated as (X).

(T4) Orifice clogging; After leaving the recording device for 3 months, the orifice tip was observed using a microscope. No clogging was observed (O), and slight clogging was observed ( The case where the nozzle was completely blocked was marked as (x).

(T5) Quality of recorded images: The recorded images have high density and are clear, and the density decrease rate is less than 1% after being exposed to indoor light for 3 months, and when immersed in water for 1 minute. The image blurring is very slight (0), the recorded image is high in density and not clear, or the image is clear but the density decreases after being exposed to indoor light for 3 months. A case where the amount exceeded 1% and significant bleeding of the image was observed when immersed in water for 1 minute was designated as (X).

(T6) Fixability for various recording materials; After 15 seconds of printing with the recording materials listed in the table below, rub the printed area with your finger to determine the presence or absence of image shift or blurring. 6. Excellent fixing with no image shift or blurring. The case where the image quality was observed was rated as (O), and the case where image shift, blurring, etc. were observed was rated as (X).

Recorded company name Classification Manufacturer Gin Tamaki High-quality paper Yamaba Kokusaku Pulp ■ Seven Star Hokuetsu Paper ■ White Botan Medium-quality paper Honshu Paper - Toyo Roshi Iv6.4 Non-size paper Toyo Roshi - Examples 2 to 6 I/FLl dye in place of the dyes shown in Table 1, namely Sui 2 (Example 2) afL3 (Example 3) #6
4 (Example 4) NfL5 (Example 5) M2S (Example 6)
) A recording liquid was prepared in the same manner as in Example 1 except for using the dye, and further inkjet recording was performed to obtain (Tt)
We examined each item in (T6). The obtained evaluation results are shown in Table 1.

Examples 7 to 12 Six types of recording liquids were prepared in the same manner as in Example 1 using a liquid medium having the composition shown below and each of the dyes used in Examples 1 to 6.

Water 60 parts by weight Polyethylene glycol (molecular weight 300) 15 tt Diethylene glycol 15 tt N-methyl-2-pyrrolidone 15//This obtained 6
Inkjet recording was performed for each of the recording liquids in the same manner as in Example 1, and each item (T+) to (T6) was examined. Table 1 shows the evaluation results obtained.

Kayaku Direct Yellow was used as a comparative recording agent.
ow Rspecial (C, 1, Direct y
Example 1
A recording liquid was prepared in the same manner as (Comparative Example 1).

Furthermore, a recording liquid was prepared in the same manner as in Example 7 using the above dye (Comparative Example 2).

Using these recording liquids, inkjet recording was carried out in the same manner as in Example 1, and each of the items (Tl) to (T6) was examined. The obtained evaluation results are shown in Table 1.

Examples 13 to 24 Each of the recording liquids prepared in Examples 1 to 12 was individually filled into feltbens, and each of them was used to write on medium-quality paper (Hakubotan, Honshu Paper) to record. The water resistance of the printed characters was examined, and the writing performance of the felt-tip pen after the cap was removed and left for 24 hours was examined.

In all of the recording liquids used in this example, the recorded prints were excellent in water resistance, and even after being left for 24 hours, no precipitation of dye etc. was observed on the pen tip, and good recording performance was observed. Indicated.

Claims (1)

[Claims] (1) In a recording liquid containing a recording agent, which is a component forming the recording liquid, and a liquid medium containing at least water and glycols for dissolving or dispersing this recording agent, the recording agent has the following general formula: (A); [wherein M is Ha, Li,
Represents either K or a base consisting of amines,
and two or one of the four M's above. NH2OH2OH2OHl Nl2(CH2CH20H)2 and N)l (CH2C)12()H)s is a base selected from the amines represented by s]. recording liquid.