JPS61285276A - Recording liquid - Google Patents

Abstract

NEW MATERIAL:The trisazo compound of formula I [A and B are (substituted) benzene ring or (substituted) naphtalene ring; m is 0 or 1; M is alkali metal, ammonium or amine]. EXAMPLE:The compound of formula II. USE:Recording liquid storable stably for a long period, usable without causing the clogging of nozzle and having high ejection response. PREPARATION:The amine of formula A-NH2 is diazotized with sodium nitrite, etc., in a mineral acid such as hydrochloric acid and then coupled with the amine of formula H-B-NH2 to obtain the monoazo compound of formula A-N= N-B-NH2. The monoazo compound is diazotized in the same manner and coupled with the naphthol compound of formula III. The obtained disazo compound of formula IV is diazotized and coupled with m-phenylenediaminesulfonic acid to obtain the objective compound.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a novel recording liquid, particularly a recording liquid suitable for a recording method in which recording is performed by ejecting the liquid from fine ejection ports (ejection orifices) provided in a print head and flying the liquid as droplets. The present invention relates to a recording liquid and a recording method using the recording liquid.

BACKGROUND ART Writing instruments (fountain pens, felt-tip pens, etc.) for recording on recording materials such as paper have conventionally used inks prepared by dissolving various dyes in water or other organic solvents.

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 by a piezo vibrator or electrostatic attraction due to the application of high voltage, various dyes are dissolved in water or organic solvents. It is known that compositions are used. However, compared to general perpetual silver and stationery ink such as felt-tip pens,
Inkjet recording liquids are required to meet more stringent conditions in many properties.

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, acids, or mixtures thereof are used), and as necessary. Various additives are added accordingly.

There are various types of such recording methods depending on the method of generating droplets and the method of controlling the flight direction of the droplets. An example of this is shown in FIG.

That is, the apparatus shown in FIG. 1 applies a recording signal to a recording head section having a piezo vibrator, and performs recording by generating droplets of recording liquid in response to the signal. In Figure 1, /
is the recording head, piezo vibrator-2a, diaphragm-211
, recording liquid inlet 3, liquid chamber in the head and discharge port (discharge orifice)! have. A recording liquid 7 stored in a storage tank B is introduced into the liquid chamber DA through a supply pipe r. Incidentally, depending on the case, an intermediate treatment means such as a pump or a filter may be provided in the middle of the supply pipe r. Then, a signal converted from a recording signal into a pulse by a signal processing means (for example, a pulse converter) 10 is applied to the piezo vibrator 2, and the pressure changes in the recording liquid in the liquid chamber in accordance with the signal. occurs. As a result, the recording liquid 2 is discharged from the discharge orifice j in the form of droplets //, and recording is performed on the surface of the recording material 7.2.

In addition to the above devices, various types of devices are known. For example, as shown in FIG. 2, as a modification of FIG. There is an apparatus in which a piezo vibrator is installed (the mechanism of droplet generation in this apparatus is essentially the same as the apparatus shown in FIG. 1). In addition, a device or machine that continuously generates charged droplets and uses a portion of the droplets for recording, applies thermal energy corresponding to the recording signal to the recording liquid in the chamber of the recording head,
Devices that generate droplets using this energy are also known.

Seven examples are shown in Figure 3-a, Figure 3-1), and Figure 3-1.

Head/3 is a glass, ceramic, or plastic plate having grooves/holes for ink to pass through, and a heat generating head/j used for thermal recording (a thin film head is shown in the figure, but is not limited to this). (not available) can be obtained by gluing them together. The heating head/j is a protective film formed of silicon oxide or the like/4. It consists of aluminum electrodes /7-/, /7-2, a heating resistor layer made of nichrome or the like, a heat storage layer /2, and a substrate 20 with good heat dissipation properties such as alumina.

When the ink 2 reaches the 2 ejection orifices, the pressure P
The symmeniscus λ3 is formed.

Now, when an electric signal is applied to the electrodes /7-/ and /7-2, the area indicated by n of the heating head /j suddenly generates heat, and bubbles are generated in the ink 2/ that is in contact with this area. The meniscus 23 protrudes due to the pressure, and the ink 2/ is ejected and becomes a recording droplet 241 from the orifice 22, and is deposited on the recording material! fly towards. Fig. 3 shows an external view of a multi-head in which a large number of heads shown in Fig. J-a are arranged. The multi-head has a glass plate core with multi-grooves, 26, and a heat-generating head 2?similar to that described in Figures J-A. It is manufactured by gluing.

Note that FIG. J-a shows nine heads/3 along the ink flow path.
Fig. 7-1) is a cross-sectional view taken along line A-B in Fig. 3-a.

Conventionally, as this type of recording liquid, for example, Tokko Shoj0-♂3
Otsu/No., Special Public Sho Jr/-%Om No., Special Public Sho J Koichi/3/
- Tokuko Akira! --/J/, No. 27, and JP-A-ShojO-ta, No. 5, there are known dyes and pigments in which various dyes and pigments are dissolved or dispersed in aqueous or non-aqueous solvents. Preferred conditions for this type of recording liquid include (1) liquid physical properties (viscosity) that match the ejection conditions (piezoelectric element drive voltage, drive frequency, orifice shape and material, orifice diameter, etc.);

surface tension, electrical conductivity, etc.).

(2) It should be stable for long-term storage and should not cause clogging.

(3) Fast fixation on the recording material (paper, film, etc.) and smooth dot periphery with 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 is attached to surrounding materials (containers, connecting tubes).

(sealing materials, etc.).

(7) Excellent safety in terms of odor, toxicity, and flammability.

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

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

The present invention was completed by a person who, after extensive research, discovered a dye suitable for the recording liquid used for this purpose.

That is, the recording liquid of the present invention includes a recording agent as a component for forming a recorded image and a liquid medium for dissolving or dispersing this recording agent, and the recording agent is expressed by the following general formula (1) ( (wherein, B represents a benzene ring or naphthalene ring which may have a substituent, m represents θ, and Fi/, M represents an alkali metal, ammonium or aquine). It is characterized by containing at least 47 species.

In the compound of general formula [I], the substituents for M and B include So, M group, lower alkyl group, lower alkoxy group, amino group, lower alkylcarbonylamino group, C00
Examples include M group and halogen atom. Note that the term "lower" as used herein means the number of carbon atoms/-. Examples of M include alkali metals, ammonium, and optionally substituted alkylamines.

In the present invention, A is 805M as a highly preferred dye.
B is a lower alkyl group and/or a naphthyl group substituted with
Alternatively, dyes in which M is TJi and Ha are phenyl groups substituted with lower alkoxy groups, and m is 0 or / are exemplified.

Specific examples of the dye having the general formula [I] contained in the recording liquid of the present invention include those having the structural formula shown in Table 1.

The dye of the present invention can be used, for example, in "New Dye Chemistry" by Yutaka Hosoda (published on December 27, 1999), Gihodo No. 3? It can be obtained by the following method according to the descriptions on page 2, line 2 to page 3, line 3, etc.

The following general formula (If) Mu-MH, ・・・・・・・・・・・・・・・(If) [
The characters in the formula are the same as the above definition] After diazotizing the amines represented by the following formula (1) in a mineral acid such as hydrochloric acid or sulfuric acid using sodium nitrite, etc. B is the same as defined above] By coupling with an amine represented by the following general formula (IV) A -N = N -B -MB2 ...
(IV) [In the formula, A and B are the same as defined above] A monoazo compound represented by the following is obtained.

The obtained monoazo compound was diazotized in a mineral acid such as hydrochloric acid or sulfuric acid using sodium nitrite, etc., and then converted into the following general formula (V
) H 803M [In the formula, m and M are the same as the above definition] By coupling with the naphthols represented by the following formula [■] O OsM [In the formula, %B and M%m are the same as the above definition ] is obtained.

This disazo compound is diazotized using sodium nitrite or the like in a mineral acid such as hydrochloric acid or sulfuric acid or an organic acid such as acetic acid, and then coupled with meta-72-2-2-diamine sulfonic acid. A water-soluble trisazo compound is obtained.

Among the above-mentioned required characteristics, these dyes are particularly stable for long-term storage compared to recording liquids using conventionally known dyes having similar chemical structural formulas (1) to (5) below. In addition to being extremely superior in not causing creases or clogging, it also has good ejection response and is clearly superior.

'HO 0INa (Food Black-, 2) (Direct Black-3/) (Direct Proof?) (Direct Black-ta) 80gNa (Direct Green-33) In the inkjet recording method, clogging of nozzles is a sign of reliability of the recording method. This is an extremely important factor from the aspect of safety, and conventionally, countermeasures have mainly been taken from a mechanical perspective, such as automatic nozzle capping (enveloping the nozzle in a saturated steam state when not in use) and manual pumps. However, it has not necessarily been fully effective.

Inkjet recording fluids mainly use water as a liquid medium for safety reasons, and generally low-volatility water-soluble organic solvents such as glycols are added to this as a wetting agent. There is. The solubility of dyes in these liquid media varies slightly depending on their structure, and generally the solubility in water and the solubility in glycols even tend to contradict each other. At the tip of the nozzle, water, which is a highly volatile component in the ink, tends to volatilize, and as a result, the concentration of glycols tends to be high in this area. Therefore, if a dye with low solubility in glycols is added to the recording liquid, there is a high risk that the dye will precipitate and cause nozzle clogging.

The dyes (1) to (5) listed above exhibit very good solubility in water, but have poor solubility in glycols. On the other hand, the dye represented by the general formula (1) used in the recording liquid of the present invention has improved solubility in glycols while maintaining solubility in water within a practically sufficient range. Therefore, it is extremely difficult to cause nozzle clogging.

According to the present invention, the physical property values such as viscosity and surface tension are kept within appropriate ranges, and the fine discharge orifice is not clogged.
It provides a recorded image with sufficiently high density without causing any damage, does not cause changes in physical properties or precipitation of solid content during storage, can record on various materials without limiting the type of recording material, and has a fast fixing speed. A recording liquid that gives large images with excellent water resistance, abrasion resistance, and resolution can be obtained.

The content of the above-mentioned color component, that is, the dye, is determined depending on the type of liquid medium component, the characteristics required of the recording liquid, etc., but generally it is 0% by weight based on the total weight of the recording liquid.
．． 1~ko θchi, preferably θ, evening~/! The range is preferably between 1 and 10 cm. Of course, these dyes can be used alone or in combination of two or more, or in combination with various dyes such as other direct dyes and acid dyes, using the dye as an essential component.

Liquid medium components for composing the recording liquid of the present invention include:
Water or a mixture of water and various water-soluble organic solvents is used. Examples of water-soluble organic solvents include methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, s
Alkyl alcohols with a carbon number of up to 100% such as ec-7' alcohol, tert-7' alcohol, and 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-λ
-Nitrogen-containing heterocyclic ketones such as bipridone, /, 3-dimethyl-coimidazolidinone; Noboralkylene glycols such as polyethylene glycol and polypropylene glycol; ethylene glycol, phlopylene glycol, butylene glycol, triethylene glycol ,/,
, 2. Alkylene glycols in which the alkylene group contains 2 to 6 carbon atoms such as t-hexanetriol, thiodiglycol, hexylene glycol, diethylene glycol: glycerin; ethylene glycol methyl ether, diethylene glycol methyl (also ethyl) ether, Examples include lower alkyl ethers of polyhydric alcohols such as ethylene glycol monomethyl (or ethyl) ether.

The content of the above-mentioned water-soluble organic solvent in the recording liquid is generally 5 to 5% by weight based on the total weight of the recording liquid. The range is preferably 10-70%, more preferably 20-50%.

The water content at this time is determined within a wide range depending on the type of Ell acid component, its composition, and the desired properties of the recording liquid, but it is generally 1/C10 to 1/C10 based on the total weight of the recording liquid. 0%, preferably 10-70%, preferably 20-70%
It is said to be within the range of 70 inches.

The recording liquid of the present invention prepared from such components has excellent recording properties (signal response, droplet formation stability, ejection stability, long-term continuous recording performance) by itself.

It is well-balanced and excellent in terms of ejection stability (after a long period of recording cessation), storage stability, fixation to recording materials, and light resistance, weather resistance, and water resistance of recorded images. In order to further improve such properties, various conventionally known additives may be further 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; pHW using buffer solutions.
Examples include A conditioner, antifungal agent, and the like.

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.

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.

The invention will be explained in more detail in the following examples.

Example/ The above components were thoroughly mixed and dissolved in a container, filtered under pressure through a Teflon filter with a pore size/μ, and then degassed using a vacuum pump to obtain a recording liquid. Using the obtained recording liquid, the following ( When T1) to (T,) were investigated, good results were obtained in all cases.

(7s) Long-term storage stability of the recording liquid: Even after the recording liquid was sealed in a glass container and stored at -20°C and 50°C for t months, no precipitation of insoluble matter was observed, and there were no changes in the physical properties or color tone of the liquid. Ganakatsu Nen.

(Ejection stability: Continuous ejection was carried out for 4% of each time in an atmosphere of room temperature, 5° C., and 0° C., and stable high-quality recording was possible from beginning to end under all conditions.

(T3) Ejection responsiveness: Intermittent ejection for seconds and ejection after standing for a month were investigated, and in both cases stable and uniform recording was achieved without clogging at the orifice tip.

(T4) Quality of recorded images: The recorded images have high density and are clear. After being exposed to indoor light for 3 months, the rate of decrease in density was less than 10%, and when immersed in water for 1 minute, there was very little smearing of the image.

(Ts) Fixability for each recording material: Printed with the recording materials listed in the table below/J seconds later, the presence or absence of image shift/bleeding was determined using a finger on the printing section.・Excellent fixing properties were exhibited with no bleeding.

Next, the recording material base is the product name.

Example λ A recording liquid having the above composition was prepared in the same manner as in Example 1, and an on-demand type multi-head (
Discharge orifice diameter! ! μ, heating resistor resistance value/jθΩ,
Similar to Example 1, K(Tt) to (Ts) were investigated using a recording device with a driving voltage of 3θV1 (frequency J KHz), and excellent results were obtained in all the study experiments.
"Nine.

Example 3 A recording liquid having the above-mentioned composition was prepared in the same manner as in Example 3, and an on-demand type multi-head (on-demand type multi-head) that performs recording by applying thermal energy to the recording liquid in the recording head to generate droplets.
Discharge orifice diameter 3! μ, heating resistor resistance value/! σΩ,
(Tl) to (T5) were investigated in the same manner as in Example 1 using a recording device having a driving voltage ZOV and a frequency of 2xuz, and excellent results were obtained in all the experimental experiments.

Example 1 A recording liquid having the above composition was prepared in the same manner as in Example 1, and an on-demand type multi-head (on-demand type multi-head) that performs recording by applying thermal energy to the recording liquid in the recording head to generate droplets.
Discharge orifice diameter 35μ, heating resistor resistance value/! OΩ,
In the same manner as in Example 1, (T1) to (T5) were investigated using a recording device having a driving voltage of 3.theta.V and a frequency of 2 KHz, and excellent results were obtained in all of the investigation experiments.

Example! A recording liquid having the above composition was prepared in the same manner as in Example 1, and an on-demand type multi-head (
Discharge orifice diameter 35μ, heating resistor resistance value/! 0Ω,
Similar to Example 1, (T1) to (Ts) were investigated using a recording device having a driving voltage of 30 v and a frequency of 2 x ug, and excellent results were obtained in all the experiments.

Examples 6 to 13 Recording liquids having the compositions shown in t to /3 below were prepared in the same manner as in Example. These compositions were filled into felt-tip pens and written on medium-quality paper (Hakubotan Nihonshu Paper Co., Ltd.) to examine water resistance and writability after the cap was removed and left for a period of λ.

The recording liquid of this example was excellent in both water resistance and writability after standing.

In addition, in Example t, instead of the dye compound AJ, KAj,
B, 7. Adjust the recording liquid using /ko, /4t, /j,
Similar to Example 1, K(Tt) to ('rs) were investigated, and good results were obtained in all the investigation experiments.

Reference Example/ [Synthesis of the compound of Example/4/] (1) Production of first diazo liquid 2-aminonaphthalene-4t, /-disulfoheptacic acid 30
．． ．． 2f was added to j% hydrochloric acid & 00 xtK and stirred for 3 hours to form a uniform slurry. Hyohiro 0θt was added to this and the mixture was cooled to 3°C. An aqueous solution of 7.3 tons of sodium nitrite dissolved in 73 tons of water was added to this slurry. Then 3℃
After diazotization by stirring for 1 hour, 3t of sulfamic acid
was added to eliminate the remaining sodium nitrite to obtain a first diazo solution.

(2) First coupling 2-1 dimethoxyaniline/! , jt were added to 4tjO- of water and stirred for 2 hours to make a homogeneous slurry.9. Is this ice 3θ0? , (1) above
Add the first diazo solution obtained in step 1 and 25% strength soda θ-, stir for 75 hours at a temperature θ ~ 3°C and pH ~ 3 to perform coupling, and then add 20 θt of common salt to perform salting out. went.

After filtering the precipitated monoazo compound, 10 times saline solution!
After washing with 00- and drying, the following monoazo compound Da/, Of was obtained.

(3) Production of the first cosiazo liquid The monoazo compound obtained in the above (2), 2! , 3f to j
% hydrochloric acid 'l-70111 and stirred for 5 hours to form a uniform slurry, then ice 3θ0f was added and cooled to 3°C.

3 water in this slurry? +dlc sodium nitrite3. ?
f was dissolved and Yoshiki's solution was added. After diazotization by stirring at 3° C. for 70 hours, remaining sodium nitrite was eliminated by adding sulfamino acid/l to obtain a first diazo solution.

(4) First coupling/-Hydroxy-7aminonaphthalene-3-sulfonic acid/JOt was added to 4t6θd of water, and then 100 g of ice
2. Add the liquid obtained in the above (2) and -5% sodium chloride to 1) H/~10, temperature -j'
Coupling was performed at C. The mixture was stirred for 5 hours at the same temperature and pHK, and then salted out by adding common salt Coj01. After filtering the precipitated good compound, it was washed with 3θOd salt solution and dried to obtain the following disazo compound! I got 7.39.

(5) Production of third diazo liquid 9 disazo compound obtained in (4) / 9,151 with 3% hydrochloric acid 4
The slurry was added to tO+lad and 100 ml of vinegar and stirred for 3 hours to form a uniform slurry, and then 200 t of ice was added and cooled to 3°C. Water in this slurry, and sodium nitrite in 201R1! ? An aqueous solution of was added. Next, diazotization was performed by stirring at 3°C for a long time, and then sulfamino acids o, r were added.
The remaining sodium nitrite was removed by adding t to obtain a third diazo solution.

(6) Third coupling/3-diaminobenzen-dasulfonic acid 4t, 7
After adding f to water/θθd, add ice! Add 0F and 3
Cool to 9°C. Next, add the tertiary diazo liquid obtained in step (5) above and bring the temperature to -! After stirring at ℃ for 70 hours and coupling, add salt! Of was added to perform salting out.

After filtering the precipitated compound, the precipitated compound was washed with -theta salt solution to obtain a wet cake. This wet cake was desalted and then dried to obtain the target compound f. The yield was 1%.

The results of elemental analysis were as follows.

Reference Example Co [Synthesis of the dye of Example 20 and 3] (1) Production of the first diazo liquid and the first coupling coat of aminonaphthalene-Hiroshi/disulfonic acid, ? λ
-Aminonaphthalene! The following monoazo compounds J4t,/f were obtained in the same manner as Reference Example/, except that -sulfonic acid 22,3t was used.

(2) Production of first diazo liquid A first diazo liquid was obtained in the same manner as in the reference example using the monoazo compound/9.9tf.

(3) Third coupling/-Hydroxy-7-amino-naphthalene-3-sulfonic acid #) K/-Hydroxy-7-7-minonaphthalene-3,6-disulfonic acid/6. The following disazo compound was prepared in the same manner as Reference Example/, except that Of was used! 2.9 f was obtained.

(4) Production of third diazo liquid Reference example/ using the disazo compound obtained in (3), ≦2
A third diazo liquid was obtained in the same manner as above.

(5) Using the third diazo liquid obtained in the third coupling (4), the target compound 10, Of was obtained in the same manner as in Reference Example. The yield was 2.5m.

The results of elemental analysis were as follows.

Reference Example 3 An example of a compound produced in the same manner as Reference Example/I is listed in Table 1 above as Kt.

[Brief explanation of drawings]

FIGS. 1 and 2 are schematic diagrams of an inkjet recording apparatus, respectively. Fig. J-A and Fig. 3-1) are a longitudinal cross-sectional view and a transverse cross-sectional view of a main part of another recording device. Fig. 3 is an external perspective view of a multi-head head shown in Figs. 3-a and 3-b. However, in the figure /...recording head, Xa...piezo vibrator, 2b...
...Vibration plate, 3...Inlet, 4t...Liquid chamber,!・・・
・Discharge orifice, 6...Storage tank, 7
...Recording fluid? ... Supply pipe, Ri... Intermediate processing means, 10... Signal processing means, //... Droplet, /-, Ko! ...recording material, S...recording signal, /4t-...liquid chamber, /! ...heat generating head. l...protective layer, /7...electrode, //...heating resistor layer, /ri...heat storage layer, 20...substrate, -g...
・Mizode 1st 2nd item 3-tit figure Zsujl'4ro procedural amendment (θen) Vsa1 Display of case Showa to year Patent application No. 1899/
No. 2 Title of the invention Recording liquid 3 Person making the amendment

Claims (2)

[Claims] (1) In a recording liquid containing a recording agent, which is a component for forming a recorded image, and a solvent for dissolving or dispersing this recording agent, the recording agent has the following general formula [I] ▲ Numerical formula, chemical formula, There are tables, etc. ▼...[I] (In the formula, A and B represent a benzene ring or naphthalene ring which may have a substituent, m represents 0 or 1, M is an alkali metal, ammonium or amines.) A recording liquid characterized by containing at least one dye represented by the following. (2) The recording liquid according to claim 1, wherein the dye represented by the general formula [I] is contained in an amount of 0.1 to 20% by weight based on the total weight of the recording liquid.