JPS62197476A - Recording liquid - Google Patents

Abstract

PURPOSE:To obtain a recording liquid which gives a recorded image having excellent vividness of color, light resistance, water resistance, resolution, etc., and has excellent long-term storage stability, delivery stability, delivery response, etc., by mixing a specified recording agent and a liquid medium for dissolving or dispersing it. CONSTITUTION:A recording agent which comprises a dye of formula I (wherein R1-3 are each R4, COOH or a benzoylamino group; R4-5 are each R7 or NH2; R6 is alkyl, alkoxy or COOH, R7-8 are each H, OH or SO3H; R9-11 are each R1 or an anilino group; the above-mentioned COOH or SO3H may form a salt with an alkali metal, NH4 or an organic amine) and/or a dye of formula II [wherein Q1 is an (OH- and/or SO3H-substituted) benzene ring or naphthalene ring; Q2 is an (alkyl-, alkoxy- or SO3H-substituted) benzene ring or naphthalene ring; R1 is H or alkoxy; R2 is H or R3; R3 is SO3H; R4 is H or acetylamino; R5 is R2, NH2 or anilino], and 0.1-20wt% dye containing C.I. Direct Blue 86 and/or C.I. Direct Blue 199, is mixed with water or a mixed solvent comprising water and a water-soluble organic solvent to be dissolved therein.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a new recording liquid (hereinafter referred to as ink), and in particular, ink is ejected from fine ejection ports (ejection orifices) provided in a recording head, and the ink is The present invention relates to an ink suitable for a method of recording by flying droplets.

(Prior art) Writing instruments (fountain pens,
(Feltben, etc.) uses inks prepared by dissolving various dyes in water or other organic solvents.

Also, in the so-called inkjet method, in which recording is performed by ejecting ink 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, ink dissolved in various dyes, wood, or organic solvents is used. is used. However, compared to ink for stationery such as general fountain pens and felt-tip pens, inkjet ink requires more stringent conditions in terms of many characteristics.

The inkjet system generates little noise and can perform high-speed recording or color recording on plain paper without any special fixing process, and various types of inkjet systems are being actively researched.

There are various methods for this type of method, but in all of them, the ink used must have physical properties such as viscosity and surface tension within appropriate ranges, and the recording material must have high dissolution stability and fine ejection. It is required to have certain characteristics such as not clogging the orifice, providing a recorded image of sufficiently high density, and not causing changes in physical properties or precipitation of solids during storage.

Furthermore, in addition to the above two characteristics, recording can be performed without limiting the type of recording material, fast fixing speed, water resistance,
Properties such as solvent resistance (particularly alcohol resistance), light resistance, abrasion resistance, and recording images with excellent resolution are also required.

However, images recorded using conventional inks, particularly water-based inks, tend to bleed, fade, or fade due to adhesion of water or exposure to light. This tendency is particularly noticeable in cyan recording, and there is a strong desire for an ink that has improved these drawbacks.

Conventionally, dyes for cyan ink include C and I.

Direct Blue 86 and C. I. The use of Direct Blue 199 has been proposed and is actually used.

Although these were relatively excellent in terms of color tone and light resistance, their water resistance was unsatisfactory. A cyan dye that satisfies these points independently has not yet been found.

An object of the present invention is to provide a cyan ink that satisfies all of the above conditions. That is, one of the discharge orifices
1. Ink that does not cause clogging, deterioration during storage, or precipitation, and has excellent recording performance, ejection stability, and ejection response.
7- It's about getting better. Another objective is to provide an ink with excellent color tone and contrast of recorded images. Another object of the present invention is to provide an ink with excellent fixing properties in which recorded images have water resistance, alcohol resistance, light resistance, and resolution. Thus, the present invention was completed by finding a combination of dyes suitable for the ink used for this purpose as a result of intensive studies.

(Disclosure of the Invention) 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, as a recording agent (a) having the following general formula: (A
) and/or a dye represented by the general formula CB).

(b)C. I. Direct Blue 86 and/or C
．． I. This is a recording liquid characterized by containing Direct Blue 199.

(However, R1, R2 and R3 in the formula - each independently represent a hydrogen atom, hydroxyl group, amitsuno, (, penzoylamino group, carboxyl group, or sulfonic acid group, and R4 and R5 each independently R6 represents either an alkyl group, an alkoxy group, or a carboxyl group; R7 and R8 each independently represent a hydrogen atom, a hydroxyl group, or a sulfonic acid group;
Indicates any of the sulfonic acid groups, R9, R10 and R
11 each independently represents a hydrogen atom, a hydroxyl group, an amine group, an anilino group, a benzoylamino group, or a carboxylsulfonic acid group, and the carboxyl group and sulfonic acid group are salt-formed with an alkali metal, ammonium, or an organic amine. ing. ) (However, Q in the above formula represents a benzene ring or naphthalene ring substituted with a hydroxyl group and/or a sulfonic acid group, and Q2 is unsubstituted or substituted with a group selected from an alkyl group, an alkoxy group, and a sulfonic acid group. R1 represents a hydrogen atom or an alkoxy group, R2 represents a hydrogen atom or a sulfonic acid group, R3 represents a sulfonic acid group, R4 represents a hydrogen atom or an acetylamine group, R5 is a hydrogen atom, ami7 group,
It represents an anilino group or a sulfonic acid group, and the sulfonic acid group is salt-formed with an alkali metal, ammonium, or organic amine. ) Next, to explain the present invention in more detail, in order to achieve the above-mentioned object of the present invention, the present inventor conducted detailed research on dyes that are recording agent components of ink, and found that a specific combination of dyes is suitable as an ink recording agent, especially an ink recording agent used in an inkjet system, and by employing such a specific combination of dyes as an ink recording agent, the color tone can be improved when used in an inkjet system. It has been discovered that an ink can be obtained that provides a recorded image that is extremely clear and satisfies required performances such as water resistance, light resistance, resolution, and alcohol resistance.

The dyes represented by the above general formulas (A) and (B) that are used in the present invention and mainly characterize the present invention may be any dye as long as it is included in the above general formulas (A) and CB). However, particularly preferred specific examples include the following. Incidentally, although a sodium salt is given as an example, the salt is not limited to a sodium salt, and may be formed with any base such as a lithium salt, a potassium salt, an ammonium salt, an organic amino group, and the like.

Igun" 21EN2A Ega" 31 Zuibo 21, :+L1. jl'la
;) UJI'la ;) Lldl
la example m match upper 1 j 5 two legs j part J1 interpretation 2 艮 Gai demonstration part i day 1 and 2 star sex promotion finished starvation 2 U sex display part day group milk 2 U biography j part J eye LL-A The ink of the present invention contains the above-described dye (A) and/or CB) as an essential component (a), and C.I. I. Direct Blue 86 and/or C. I. The main feature is that it is used as a recording agent in combination with Direct Blue 199 as the essential component (b), and the ink obtained by such a specific combination is significantly superior to conventional inks of the same color. It provides a recorded image that has color clarity, light fastness, water resistance, etc.

The total content of the above dyes depends on the type of liquid medium components,
It is determined depending on the characteristics required for the ink, but generally it is 0.1% by weight based on the total weight of the ink.
~20%, preferably 0.5~15%, more preferably 1~10%. In the amount of these dyes used, dye (A) and/or (B) in the total amount of dye
The effects of the present invention are most significantly achieved when it is used in an amount of 10 to 90% by weight, preferably 20 to 80% by weight of the total weight. Of course, in addition to these specific dyes, various dyes such as other direct dyes and acid dyes can be used in combination.

A suitable solvent for use in the ink of the present invention is water or a mixed solvent of water and a water-soluble organic solvent, and particularly preferred is a mixed solvent of water and a water-soluble organic solvent, which is a water-soluble organic solvent. It contains polyhydric alcohol, which has the effect of preventing ink from drying, as a solvent. In addition, as water, it is preferable to use deionized water rather than ordinary water containing various ions.As for the water-soluble organic solvent used in combination with water, for example, methyl alcohol, ethyl alcohol, etc. , C1-4 alkyl alcohols such as n-7' alcohol, isobutyl alcohol, n-butyl alcohol, 5ec-butyl alcohol, tart-butyl alcohol, and isobutyl alcohol; amides such as dimethylformamide and dimethylacetamide; Ketones or keto alcohols such as acetone and diacetone alcohol; ethers such as tetrahydrofuran and dioxane; polyalkylene glycols such as polyethylene glycol and polypropylene glycol; ethylene glycol, propylene glycol, butylene glycol, 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 (or ethyl) ether, diethylene glycol methyl (or ethyl) Examples include lower alkyl ethers of polyhydric alcohols such as ether and triethylene glycol monomethyl (or ethyl) ether; N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, and the like. Among these many water-soluble organic solvents, polyhydric alcohols such as diethylene glycol, triethylene glycol monomethyl (or ethyl)
Lower alkyl ethers of polyhydric alcohols such as ethers are preferred.

The content of the water-soluble organic solvent in the ink is generally in the range of 5 to 95% by weight, preferably 10 to 80% by weight, more preferably 20 to 50% by weight based on the total weight of the ink. be.

The water content at this time is determined within a wide range depending on the type of the solvent component, its composition, and the desired characteristics of the ink, but it is generally 10 to 90% of the total weight of the ink.
Preferably 10-70%, more preferably 20-70%
is considered to be within the range that occupies

The ink of the present invention, which is formulated from such components, has excellent recording properties (signal response, stability of droplet formation, ejection stability, long-term continuous recording, ejection after a long recording pause). Stability) Storage stability, fixability to recording materials, color clarity of recorded images, light resistance, weather resistance, water resistance, alcohol resistance, etc. are all well-balanced and excellent.

In order to further improve such properties, various conventionally known additives may be 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 jetanolamine and triethanolamine; pH modifiers using buffer solutions; Antifungal agents and the like can be mentioned.

Furthermore, in order to formulate ink used in an inkjet system of the iF type, resistivity adjusters such as inorganic salts such as lithium chloride, ammonium chloride, and sodium chloride are added.

Note that when applied to an inkjet system in which ink 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 inks of the present invention as described below are useful as recording inks for various writing instruments, recording instruments, etc., and are particularly useful as inkjet inks.

As a preferable example, the inkjet method may be any method as long as it can effectively separate the ink from the nozzle and apply the ink to the recording material that is the projectile. , Representative methods of these methods include, for example, IEEE Trans Actions on Industry Applications (IEEE Trans Actions on Industry Applications).
ons onIndustr7 Applicat
ions) Vol, JA-13, No. 1 (1
February/March 977 issue), Nikkei Electronics 197
April 18, 1973 issue, January 29, 1973 issue and 19
It is listed in the May 6, 1974 issue. The methods described above are suitable for use with the ink of the present invention.To explain some of them, there is an electrostatic suction method. A method in which a strong electric field is applied between the accelerating electrode and the ink particles is drawn out from the nozzle one after another, and an information signal is given to the deflection electrodes while the drawn ink flies between the deflection electrodes to record the ink particles. There is a method of ejecting ink particles in response to an information signal without deflecting the information signal, and both methods are effective for the ink of the present invention.

The second method is to apply high pressure to the ink with a small pump and mechanically vibrate the nozzle with a crystal oscillator, etc., to forcibly eject minute ink particles. At the same time as the injection, it is charged according to the information signal. When the charged ink particles pass between the deflection electrode plates, they are deflected according to the amount of charge. Another method using this method is called the microdot inkjet method. In this method, ink pressure and excitation conditions are kept within a certain range of appropriate values, and two types of ink droplets, large and small, are ejected from the nozzle tip. Only small and medium-sized droplets are generated and used for recording. The feature of this method is that it is possible to obtain a group of minute droplets even with a conventionally large nozzle diameter.

A third method is a piezo element method, in which a piezo element is used as a pressure means for applying pressure to the ink, rather than a mechanical means such as a pump as in other methods. This method applies an electric signal to a piezo element to cause mechanical displacement, thereby applying pressure to the ink and ejecting it from a nozzle.

In addition, an inkjet method is disclosed in Japanese Patent Application Laid-Open No. 54-51837, in which ink subjected to the action of thermal energy undergoes a sudden change in volume, and the acting force due to this state change causes the ink to be ejected from a nozzle. can also be used effectively.

The ink of the present invention as described above employs a specific combination of blended dyes as its recording agent, and thus has excellent long-term storage stability and is suitable not only as an ink for general recording, but also as an ink for use in inkjet systems in particular. It has recording properties such as ejection stability and ejection response, and when added to the recording material, it exhibits excellent ink fixing properties, especially color clarity, light resistance, water resistance, alcohol resistance,
This provides recorded images with excellent resolution and the like.

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

Example 1 C. I. Direct Blue 86 3 parts Exemplary compound (3) 2 parts Diethylene glycol 30 parts Ion-exchanged water 65 parts The above ingredients were thoroughly mixed and dissolved in a container, filtered under pressure with a Teflon filter with a pore size of 1 gm, and then desorbed using a vacuum pump. The ink (I) of the present invention was obtained by air treatment.

Comparative Example 1C. I. Direct Blue 86 5 parts diethylene glycol 30 parts ion exchange water
Ink (II) of a comparative example was obtained in the same manner as in Example 1 except that 65 parts of the above components were used.

Comparative Example 2 Exemplary Compound (3) 5 parts Diethylene glycol 30 parts Ion-exchanged water 65 parts An ink (m) of a comparative example was obtained in the same manner as in Example 1 except that the above components were used.

Example of use! Using the inks (I) to (m) obtained above, an on-demand recording head that ejects ink using a piezoelectric vibrator (discharge orifice diameter 5゜m, piezoelectric vibrator drive voltage 80V, frequency fi 3KHz) Recording was performed using a recording device having the following, and the results shown in Table 1 below were obtained.

Ink h・(1)
No change No change Clear (11)
No change Considerable fading Brightness (m) Considerable fading No change Dullness direction and light resistance were determined visually after 100 hours of irradiation using a xenon fade meter.

Water resistance was determined visually after being immersed in water for 24 hours.

Color tone was determined visually.

Examples 2 to 6 Inks having the compositions shown in Table 2 below were prepared in the same manner as in Example 1 and examined in the same manner as in Example 1, and similarly excellent images were obtained.

In addition, regarding these inks, on-demand type multi-heads (with an ejection orifice diameter of 35
gm, heating resistor resistance value 1501G, driving pressure 30V
, a frequency of 92 KHz) was used in Example 1.
We conducted the same study as above, and obtained excellent results in all of the study experiments.

t.2-=Example 2C. I. Direct Blue 86 4 parts Exemplary compound (8) 3 parts Ethylene glycol 30 parts Water
63 parts Example 3 C. I. Direct Blue 86 2 parts Exemplary compound (15) 3 parts diethylene glycol 25 parts Water
70 copies Example 4 C. I. Direct Blue 86 4 parts Exemplary compound (34) 4 parts N-methyl-
2-pyrrolidone 20 parts water
72 parts Example 5 C. I. Direct Blue 199 3 parts Exemplary compound (29) 6 parts Diethylene glycol 7 parts Methyl ether 30 parts Water
61 parts Example 6

Claims (1)

[Claims] (1) In a recording liquid that includes 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 includes (a) a dye represented by the following general formula (A); / or a dye represented by general formula (B); and (b) C.I. I.
Direct Blue 86 and/or C. I. A recording liquid characterized by containing Direct Blue 199. ▲There are mathematical formulas, chemical formulas, tables, etc.▼(A) (However, R1, R2, and R3 in the above formula are each independently a hydrogen atom, a hydroxyl group, an amino group, a benzoylamino group, a carboxyl group, or a sulfonic acid group) and R
4 and R5 each independently represent a hydrogen atom, a hydroxyl group, an amino group, or a sulfonic acid group, and R6 is an alkyl group,
Indicates either an alkoxy group or a carboxyl group, R7
and R8 each independently represent a hydrogen atom, a hydroxyl group, or a sulfonic acid group, and R9, R10, and R11 each independently represent a hydrogen atom, a hydroxyl group, an amino group, an anilino group,
It represents any one of a benzoylamino group, a carboxyl group, and a sulfonic acid group, and the carboxyl group and the sulfonic acid group are salt-formed with an alkali metal, ammonium, or an organic amine. ) ▲There are mathematical formulas, chemical formulas, tables, etc.▼(B) (However, Q in the above formula represents a benzene ring or naphthalene ring substituted with a hydroxyl group and/or a sulfonic acid group, and Q2 is unsubstituted or an alkyl group, Represents a benzene ring or naphthalene ring substituted with a group selected from an alkoxy group and a sulfonic acid group, R1 represents a hydrogen atom or an alkoxy group, R2 represents a hydrogen atom or a sulfonic acid group, and R3 represents a sulfonic acid group. , R4 represents a hydrogen atom or an acetylamino group, R5 represents a hydrogen atom, an amino group,
It represents an anilino group or a sulfonic acid group, and the sulfonic acid group is salt-formed with an alkali metal, ammonium, or organic amine. )