JPH038670B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention uses a new recording liquid, particularly a recording liquid suitable for a recording method in which recording is performed by ejecting from a fine ejection orifice provided in a recording head and flying droplets, and the recording liquid is used. Concerning the recording method used. 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. In addition, in the so-called inkjet recording method, in which recording is performed by ejecting the liquid in the recording head from the 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 inks for stationery such as general fountain pens and felt pens, recording liquids for ink jets require more stringent conditions in terms of many characteristics. This type of inkjet recording method uses droplets of a recording liquid called ink to fly.
Recording is performed by attaching this 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 or various organic solvents or a mixture thereof is used), and if necessary, Various additives are added. 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 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 FIG. 1, reference numeral 1 denotes a recording head, which has a piezo vibrator 2a, a diaphragm 2b, an inlet 3 for recording liquid, a liquid chamber 4 in the head, and an ejection port (ejection orifice) 5. A recording liquid 7 stored in a storage tank 6 is introduced into the liquid chamber 4 through a supply pipe 8 . Incidentally, an intermediate treatment means 9 such as a pump or a filter may be provided in the middle of the supply pipe 8 depending on the case. And in the piezo vibrator 2a,
A signal converted from the recording signal S into a pulse by a signal processing means (for example, a pulse converter) 10 is applied, and a pressure change occurs in the recording liquid in the liquid chamber 4 in accordance with the signal. As a result, the recording liquid 7 is discharged from the discharge orifice 5 in the form of droplets 11, and recording is performed on the surface of the recording material 12. In addition, various types of devices other than the above-mentioned 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, there is a device that continuously generates charged droplets and uses a portion of the droplets for recording, or a device that applies thermal energy corresponding to the recording signal to the recording liquid in the chamber of the recording head section, and uses the energy to generate droplets. Also known are devices that generate . An example thereof is shown in Fig. 3-a, Fig. 3-b, and Fig. 4. The head 13 is made of glass, ceramic, plastic plate, etc. having grooves 14 through which ink passes, and a heat generating head 15 used for thermal recording (a thin film head is shown in the figure, but is not limited to this). Obtained by gluing. Heat generating head 1
5 is made up of a protective film 16 made of silicon oxide or the like, aluminum electrodes 17-1 and 17-2, a heating resistor layer 18 made of nichrome or the like, a heat storage layer 19, and a substrate 20 with good heat dissipation properties such as alumina. It's on. The ink 21 has reached the discharge orifice 22 and forms a meniscus 23 due to the pressure P. Now, when an electric signal is applied to the electrodes 17-1 and 17-2, the area indicated by n of the heating head 15 suddenly generates heat, bubbles are generated in the ink 21 in contact with this area, and the pressure causes the meniscus 23 to rise. protrudes, and the ink 21 is ejected from the orifice 22 into a recording droplet 2.
4 and flies toward the recording material 25. Fourth
The figure shows an external view of a multi-head in which a large number of heads shown in Figure 3-a are arranged. The multi-head is manufactured by gluing together a glass plate 27 having multi-grooves 26 and a heating head 28 similar to that described in FIG. 3-a. Note that FIG. 3-a is a sectional view of the head 13 along the ink flow path, and FIG. 3-b is a cross-sectional view taken along line A-B in FIG. 3-a. Conventionally, as this type of recording liquid, for example,
−8361, Special Publication No. 51-40484, Special Publication No. 13126, Special Publication No. 52-13126
As shown in Japanese Patent Publication No. 52-13127 and Japanese Patent Application Laid-Open No. 50-95008, various dyes and pigments are dissolved or dispersed in aqueous or non-aqueous solvents. The preferred conditions for this type of recording liquid are (1) liquid physical properties (viscosity, surface tension, electrical conductivity, etc.) that match the ejection conditions (piezoelectric element drive voltage, drive frequency, orifice shape and material, orifice diameter, etc.); have the following. (2) Stable for long-term storage and should not cause clogging. (3) Fixation is fast on the recording material (paper, film, etc.) and the dot periphery is smooth with little bleeding. (4) The color tone of the printed image is clear and the density is high. (5) The printed image must have 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, flammability, etc. 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. 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 present invention provides a recording liquid containing a recording agent as a component for forming a recorded image and a liquid medium for dissolving or dispersing this recording agent, in which the recording agent is represented by the following general formula [A]. (In the formula, X is a hydrogen atom, and the lower alkyl group is
SO ₃ represents a phenyl group which may be substituted with M group, m represents 0 or 1, M represents an alkali metal, ammonium or amines, A, B
and C represents a benzene or naphthalene ring which may have a substituent, and B and C do not represent a naphthalene ring at the same time. Regarding liquid. In the compound of the general formula [], A, B, C
Examples of the substituent include SO ₃ M group, lower alkyl group, lower alkoxy group, lower alkylcarbonylamino group, COOM group, halogen atom, and the like.
In addition, the term "lower" as used herein means a carbon number of 1 to 4. In addition, M is an alkali metal, ammonium,
Examples include alkylamines which may be substituted. In the present invention, more preferred dyes include phenyl in which A is substituted with SO ₃ M and may be further substituted with a lower alkyl group or lower alkoxy group, and B is substituted with a lower alkyl group or a lower alkoxy group. A dye in which C is a naphthyl group substituted with SO ₃ M or a phenyl group substituted with a lower alkyl group or a lower alkoxy group, X is H, m is 1, and M is Na or Li, respectively. can be mentioned. Specific examples of the dye having the general formula [] contained in the recording liquid of the present invention include those having the structural formula shown in Table 1.

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[Table] The dyes of the present invention are, for example, "New Dye Chemistry" by Yutaka Hosoda (published December 21, 1970), Gihodo, p. 397, No. 27.
It can be obtained by the following method according to the description in lines to page 398, line 19, etc. After diazotizing amines represented by the following general formula [] A-NH ₂ ... [] [In the formula, A is the same as defined above] using sodium nitrite in a mineral acid such as hydrochloric acid or sulfuric acid, the following By coupling with amines represented by the general formula [] H-B-NH ₂ ... [] [In the formula, B is the same as the above definition], the following general formula [] [In the formula, A and B are the same as the above definition] Same] A monoazo compound represented by A-N=N-B-NH ₂ ...[] can be obtained. The obtained monoazo compound is diazotized using sodium nitrite or the like in a mineral acid such as hydrochloric acid or sulfuric acid, and then converted to the following general formula [] H-C-NH ₂ ... [] [In the formula, C is as defined above] The following general formula A-N=N-B-N=N-C-NH ₂ can be obtained by coupling with amines represented by
...[] [In the formula, A, B, and C are the same as defined above] A disazo compound represented by the following is obtained. The obtained disazo compound is diazotized using sodium nitrite, etc. in a mineral acid such as hydrochloric acid or sulfuric acid or an organic acid such as acetic acid, and then the following general formula [] [In the formula, X, M, and m are the same as defined above.] By coupling with a naphthol represented by the following formula, the water-soluble trisazo compound of the present invention can be obtained. These dyes have the above-mentioned required properties, especially stability for long-term storage, compared to recording liquids using conventionally known dyes having similar chemical structural formulas (1) to (5) below. It is extremely superior in that it does not cause clogging, and it also has good light resistance, so its clear superiority is recognized. In the inkjet recording method, nozzle clogging is a very important factor in terms of the reliability of the recording method. Conventionally, for example, automatic capping of the nozzle (enveloping the nozzle in a saturated vapor state when not in use) was used. Mechanical countermeasures, such as manual pumps and other countermeasures, have been proposed, but they have not always been sufficiently effective. Recording fluids for inkjet use mainly water-based liquid media for safety reasons, and generally low-volatility water-soluble organic solvents such as glycols are added to this as wetting agents. 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 therefore the concentration of glycols tends to increase 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 [] used in the recording liquid of the present invention is
It has improved solubility in glycols while maintaining its solubility in water within a practically sufficient range, and is therefore extremely unlikely to cause nozzle clogging. According to the present invention, physical property values such as viscosity and surface tension are within appropriate ranges, do not clog the fine discharge orifice, provide recorded images with sufficiently high density, and prevent changes in physical property values during storage. Alternatively, a recording liquid that does not cause solid content precipitation, can record on various materials without limiting the type of recording material, has a high fixing speed, and provides images with excellent water resistance, abrasion resistance, and resolution. can get. 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 is generally 0.1 to 0.1% by weight based on the total weight of the recording liquid. 20%, preferably 0.5
It is in the range of ~15%, more preferably 1~10%. 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. As a liquid medium component for composing the recording liquid of the present invention, water or a mixture of water and various water-soluble organic solvents is used. Examples of water-soluble organic solvents include alkyl alcohols having 1 to 4 carbon atoms such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, and isobutyl alcohol. Alcohols; 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
-Nitrogen-containing heterocyclic ketones such as imidazolidinone; polyalkylene glycols such as polyethylene glycol and polypropylene glycol; ethylene glycol, propylene glycol, butylene glycol, triethylene glycol, 1,
Alkylene glycols in which the alkylene group contains 2 to 6 carbon atoms, such as 2,6-hexanetriol, 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 ethylene glycol monomethyl (or ethyl) ether. The content of the water-soluble organic solvent in the recording liquid is generally 5% by weight based on the total weight of the recording liquid.
~95%, preferably 10-80%, more preferably 20
It is said to be in the range of ~50%. The water content at this time depends on the type of solvent component mentioned above,
Although it is determined within a wide range depending on the composition and desired properties of the recording liquid, it is generally 10 to 90%, preferably 10 to 70%, more preferably 20 to 70% of the total weight of the recording liquid. considered to be within the range. The recording liquid of the present invention prepared from such components has excellent recording properties (signal response, stability of droplet formation, ejection stability, long-term continuous recording, and long-term recording cessation). discharge stability), storage stability,
Fixability to recording material or light resistance of recorded images,
Weather resistance, water resistance, etc. are both well-balanced and excellent. In order to further improve such properties, various conventionally known additives may be further added. For example, viscosity modifiers such as polyvinyl alcohol, celluloses, and water-soluble resins; various cationic, anionic, or nonionic surfactants; surface tension modifiers such as diethanolamine and triethanolamine; PH modifiers using buffer solutions, and mold prevention agents. Agents, etc. can be mentioned. Further, in order to prepare the recording liquid used in the type of inkjet recording method in which the recording liquid is charged, a resistivity adjusting agent such as inorganic salts such as lithium chloride, ammonium chloride, and sodium chloride is added. Note that when applied to an inkjet method in which the recording liquid is ejected by the action of thermal energy, the thermal properties (e.g., specific heat, coefficient of thermal expansion, thermal conductivity, etc.) may be adjusted. be. The invention will be explained in more detail in the following examples. Example 1 Ion exchange water (hereinafter abbreviated as water) 71 parts by weight diethylene glycol 25 No. 1 dye 4 The above components were thoroughly mixed and dissolved in a container, and filtered under pressure using a Teflon filter with a pore size of 1μ. ,
The recording liquid was degassed using a vacuum pump.
Using the obtained recording liquid, an on-demand recording head (discharge orifice diameter 50μ, piezo vibrator drive voltage
By a recording device with 60V, frequency 4KHz),
When the following examinations were conducted for T ₁ to _{T 5} , good results were obtained in all cases. (T ₁ ) Long-term storage stability of the recording liquid: Even after the recording liquid was sealed in a glass container and stored at -30℃ and 60℃ for 6 months, no precipitation of insoluble matter was observed, and the physical properties and color tone of the liquid remained unchanged. There was no change. (T ₂ ) Ejection stability: Continuous ejection was performed for 24 hours in an atmosphere of room temperature, 5° C., and 40° C. Under all conditions, stable high-quality recording was possible from beginning to end. (T ₃ ) Ejection response: Intermittent ejection for 2 seconds and ejection after being left for 2 months were investigated, and in both cases, stable and uniform recording was achieved without clogging at the tip of the orifice. (T ₄ ) Quality of recorded images: The recorded images had high density and were clear. After 3 months of exposure to room light, the density reduction rate was less than 1%, and when immersed in water for 1 minute, there was very little blurring of the image. (T ₅ ) Fixability on various recording materials: After 15 seconds of printing on the recording materials listed in the table below, the printed area was rubbed with a finger to determine the presence or absence of image shift and bleeding.
All of them exhibited excellent fixing properties with no image shift or blurring.

[Table] However, the name of the recording material is the product name. Example 2 Water 62 parts by weight N-methyl-2-pyrrolidone 15 Diethylene glycol 19 Dye No. 2 4 A recording liquid having the above composition was prepared in the same manner as in Example 1, and added to the recording liquid in the recording head. On-demand type multi-head that applies thermal energy to generate droplets and performs recording (discharge orifice diameter 35μ, heating resistor resistance 150Ω, drive voltage 30V, frequency 2K)
Hz) in the same manner as in Example 1 using a recording device with
Studies were carried out for T ₁ to T ₅ , and excellent results were obtained in all the studies. Example 3 Water 45 parts by weight Ethylene glycol 20 1,3-dimethyl-2-imidazolidinone
30 〃 Dye No. 7 5 〃 A recording liquid having the above composition was prepared in the same manner as in Example 1, and an on-demand type recording liquid was prepared by applying thermal energy to the recording liquid in the recording head to generate droplets. Multi-head (discharge orifice diameter 35μ, heating resistor resistance value 150Ω, drive voltage 30V, frequency 2K
Hz) in the same manner as in Example 1 using a recording device with
Studies were carried out for T ₁ to T ₅ , and excellent results were obtained in all the studies. Example 4 Water 60 parts by weight Diethylene glycol 36 Dye No. 10 4 A recording liquid having the above composition was prepared in the same manner as in Example 1, and thermal energy was applied to the recording liquid in the recording head to generate droplets. On-demand type multi-head that performs continuous recording (discharge orifice diameter 35μ, heating resistor resistance value 150Ω, drive voltage 30V, frequency 2K)
Hz) in the same manner as in Example 1 using a recording device with
Studies were carried out for T ₁ to T ₅ , and excellent results were obtained in all the studies. Example 5 Water 66 parts by weight diethylene glycol monomethyl ether
30 〃 Dye No. 11 4 〃 A recording liquid having the above composition was prepared in the same manner as in Example 1, and an on-demand type recording liquid was prepared by applying thermal energy to the recording liquid in the recording head to generate droplets. Multi-head (discharge orifice diameter 35μ, heating resistor resistance value 150Ω, drive voltage 30V, frequency 2K
Hz) in the same manner as in Example 1 using a recording device with
Studies were carried out for T ₁ to T ₅ , and excellent results were obtained in all the studies. Examples 6 to 13 Recording liquids having the compositions shown below in 6 to 13 were prepared in the same manner as in Example 1. These compositions were filled into felt pens and written on medium-quality paper (Hakubotan: Honshu Paper Industries) to examine water resistance and writability after removing the cap and leaving it for 24 hours. The recording liquid of this example was excellent in both water resistance and writability after standing. 6-water diethylene glycol No. 3 dye 71 parts by weight 25 〃 4 〃 7-water ethylene glycol N-methyl-2-pyrrolidone No. 13 dye 45 parts by weight 20 〃 30 〃 5 〃 8-water ethylene glycol monomethyl ether No. 15 Dye 60 parts by weight 35 〃 5 〃 9 Water diethylene glycol No. 18 dye 76 parts by weight 20 〃 4 〃 10 Water N-methyl-2-pyrrolidone ethylene glycol dimethyl ether No. 20 dye 60 parts by weight 15 〃 20 〃 5 〃 11 Water diethylene glycol No. 2 dye 71 parts by weight 25 〃 4 〃 12 Water ethylene glycol monomethyl Ether No. 4 dye 60 parts by weight 35 〃 5 〃 13 Water N-methyl-2-pyrrolidone ethylene glycol dimethyl Ether No. 16 Dye 60 parts by weight 15 〃 20 〃 5 〃 In addition, in Example 6, instead of dye compound No. 3
Using dye compounds No. 6, 8, 9, and 17, recording liquids were prepared using dye compounds No. 10, 12, 14, and 19 instead of dye compound No. 5 in Example 2, and the same procedure as in Example 1 was carried out. Studies were carried out at T ₁ to T ₅ , and good results were obtained in all the experiments. Reference Example 1 [Synthesis of Compound No. 1 of Example 1] (1) Production of first diazo liquid Add 17.3 g of methanic acid to 346 ml of 3% hydrochloric acid,
A homogeneous slurry was obtained by stirring for a period of time. Ice in this
200g was added and cooled to 3°C. An aqueous solution of 7.3 g of sodium nitrite dissolved in 73 ml of water was added to this slurry. Next, after diazotization by stirring at 3° C. for 1 hour, 3 g of sulfamic acid was added to eliminate remaining sodium nitrite to obtain a first diazo solution. (2) First coupling orthoanisidine 12.3g was added to 450ml of 50% methanol water and dissolved. To this, add 300 g of ice, the first diazo solution obtained in (1) above, and 10 ml of 25% caustic soda, and heat the mixture at a temperature of 0 to 3°C.
After coupling by stirring at pH 2 to 3 for 15 hours, 200 g of common salt was added to perform salting out. After filtering out the precipitated monoazo compound, add 10% saline 500ml
Wash with ml and dry the following monoazo compound 28.2g was obtained. (3) Production of second diazo liquid 15.4g of the monoazo compound obtained in (2) above was added to 5%
After adding 300 ml of hydrochloric acid and stirring for 5 hours to make a uniform slurry, 250 g of ice was added and the mixture was cooled to 3°C. An aqueous solution of 3.8 g of sodium nitrite dissolved in 38 ml of water was added to this slurry. After diazotization by stirring at 3° C. for 10 hours, 1 g of sulfamic acid was added to eliminate remaining sodium nitrite to obtain a second diazo solution. (4) Second coupling 1-amino-naphthalene-7-sulfonic acid 11.2
g to 230 ml of water, add 400 g of ice, and add (2) above.
10 ml of the second diazo solution and 25% caustic soda obtained in
was added and coupling was performed at pH 2-3 and temperature 2-5°C. After stirring for 5 hours at the same temperature and pH,
Salting out was performed by adding 100 g of common salt. After filtering out the precipitated compounds, wash with 300 ml of 10% saline solution,
After drying, 23.8 g of the following disazo compound was obtained. (5) Production of third diazo liquid 13.5g of the disazo compound obtained in (4) was added with 3% hydrochloric acid
ml and 100 ml of acetic acid, stirred for 3 hours to form a homogeneous slurry, then added 300 g of ice and cooled to 3°C. Sodium nitrite in 20ml of water in this slurry
An aqueous solution containing 1.8 g was added. Then, after diazotization by stirring at 3°C for 24 hours, sulfamic acid
0.5 g was added to eliminate the remaining sodium nitrite to obtain a third diazo solution. (6) Third coupling 1-hydroxy-7-amino-naphthalene
After adding 8.0 g of 3,6-disulfonic acid to 320 ml of water, 600 g of ice, the tertiary diazo solution obtained in (5) above, and 45 ml of 25% caustic soda were added to the mixture to bring the pH to 8-10 and the temperature to 2-5. Coupling was performed at ℃. Same temperature and same PH
After stirring for 5 hours, 250 g of common salt was added to perform salting out. After filtering out the precipitated compounds, add 400ml of 20% saline.
85 g of wet cake was obtained. This wet cake is desalinated and then dried to produce the desired compound. 18.3g was obtained. The yield was 76.3%. The results of elemental analysis were as follows.

[Table] Reference Example 2 [Synthesis of dye No. 7 of Example 3] (1) Production of first diazo liquid 2-amino-naphthalene- instead of methanic acid
A first diazo liquid was obtained in the same manner as in Reference Example 1 except that 30.2 g of 4,8-disulfonic acid was used. (2) First coupling 2-methoxy-5- instead of orthoanisidine
The following monoazo compound was prepared in the same manner as in Reference Example 1 except that 18.0 g of acetylamino-aniline was used. 42.4g was obtained. (3) Production of second diazo liquid A second diazo liquid was obtained in the same manner as in Reference Example 1 using 24.7 g of the monoazo compound obtained in (2) above. (4) Second coupling The following disazo compound was prepared in the same manner as in Reference Example 1 except that 5.4 g of orthotoluidine was used instead of 1-amino-naphthalene-7-sulfonic acid. 23.2g was obtained. (5) Production of third diazo liquid A third diazo liquid was obtained in the same manner as in Reference Example 1, except that 15.3 g of the disazo compound obtained in (4) above was used. (6) Third coupling 1-hydroxy-7-(3'-sulfophenyl)-
The desired compound was prepared in the same manner as in Reference Example 1 except that 9.9 g of amino-naphthalene-3-sulfonic acid was used. 19.6g was obtained. The yield was 71.1%. The results of elemental analysis were as follows.

[Table] Reference Example 3 Examples of compounds produced in the same manner as Reference Examples 1 and 2 are summarized in Table 1 above.

[Brief explanation of the drawing]

1 and 2 are schematic diagrams of an inkjet recording apparatus, respectively. Figures 3-a and 3-b are a vertical sectional view and a horizontal sectional view of a main part of another recording device. FIG. 4 is an external perspective view of a multi-head head shown in FIGS. 3-a and 3-b. However, in the figure, 1...recording head, 2a...
...Piezo vibrator, 2b...Vibration plate, 3...Inflow port, 4...Liquid chamber, 5...Discharge orifice, 6...
Storage tank, 7... Recording liquid, 8... Supply pipe, 9...
...Intermediate processing means, 10...Signal processing means, 11...
...Droplet, 12, 25... Recording material, S... Recording signal, 14... Liquid chamber, 15... Heat generating head, 16...
... protective layer, 17 ... electrode, 18 ... heating resistor layer, 19 ... heat storage layer, 20 ... substrate, 26 ... groove.

Claims (1)

[Claims] 1. In a recording liquid containing a recording agent as 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 [] (wherein, X is a hydrogen atom, a lower alkyl group, or
SO ₃ represents a phenyl group which may be substituted with M group, m represents 0 or 1, M represents an alkali metal, ammonium or amines, A, B
and C represents a benzene ring or a naphthalene ring which may have a substituent, and B and C do not represent a naphthalene ring at the same time. Black recording liquid. 2. The black recording liquid according to claim 1, wherein the dye represented by the general formula [] is contained in an amount of 0.1 to 20% by weight based on the total amount of the recording liquid.