JPS5925850A - Recording liquid - Google Patents

Abstract

PURPOSE:To provide a fuchsine-colored recording liquid of high homogeneity and light resistance, highly stable for a long period, virtually free from clogging in delivery olifice, suitable for ink-jet system and recording utensils, containing specific water-soluble dyes such as C.I. Direct Red 75 and 89. CONSTITUTION:The objective recording liquid comprising (A) pref. 1-10wt% of a combination of water-soluble dyes consisting of (i) at least one sort of dye selected from C.I. Direct Red 75, 83, 83:1, and 240, C.I. Acid Red 119, 119:1, 217, 218, 228, 299, and 328, and (ii) at least one sort of dye selected from C.I. Direct Red 89, 79, 80, 81, and 99, C.I. Acid Red 8, 355, 366, 337, 42, 57, 151, 158, and 252 pref. in a ratio (i)/(ii) of 1/9-9/1 and (B) pref. 2-50wt% of an water-soluble organic solvent such as diethylene glycol, and (C) water. EFFECT:Having high setting potential and giving printed images of excellent water and wear resistance.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a recording liquid, particularly a magenta color recording liquid, which is suitable for use in an inkjet system or a writing instrument in which recording is performed by ejecting droplets from an orifice of a recording head.

Various types of ink shed recording methods are being actively researched because they generate less noise, do not require special fixing on plain paper, and can perform high-speed recording. The recording liquid used in these inkjet recording methods must have physical properties such as viscosity and surface tension within appropriate ranges, must not clog the fine ejection ports (orifices), and must have a clear color tone that is sufficient. It is required to have certain characteristics such as providing a recorded image with a high density and not causing changes in physical properties or precipitation of solid content during storage.

Furthermore, in addition to these characteristics, recording can be performed without restricting the type of recording material such as paper, fast fixing speed to recording material, water resistance, solvent resistance (especially alcohol resistance) ), light fastness, abrasion resistance, and the ability to provide images with excellent resolution.

The recording liquid used in the inkjet recording method is basically composed of a dye as a recording agent and its solvent, so the characteristics of the recording liquid described above 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.

In particular, the solubility of the recording liquid in the liquid medium is important, and having sufficient solubility in water and in wetting agents, which are generally organic solvents, is essential for good clogging prevention. It also serves as the basis for maintaining the dissolution stability of the recording agent.

On the other hand, when obtaining a full-color recorded image using the inkjet recording method, magenta and yellow are used.

Recording liquids of the three primary colors of cyan or recording liquids of the four primary colors with a blank added thereto are used, and the color tone of the recorded image is determined by subtractive color mixing. In this case, in order to obtain a recorded image with a desired tone, it is required that the hues of these recording liquids exhibit ideal primary colors of magenta, yellow, or cyan, respectively, and have high chroma. Therefore, it is an extremely important technique to select a dye in consideration of all the color tones exhibited by the recording liquid.

However, with regard to conventionally known magenta recording liquids, there is almost no one that fully satisfies the above-mentioned properties, especially solubility, color tone, light resistance, etc.; Development was strongly desired.

An object of the present invention is to provide a recording liquid that has high solubility in liquid medium components or long-term dissolution stability and is less likely to cause clogging of ejection orifices.

Another object of the present invention is to provide a magenta recording liquid for full-color inkjet recording that exhibits an ideal magenta color and has excellent light resistance.

The above and other objects are achieved by the invention as follows.

That is, the present invention comprises a liquid composition containing a water-soluble dye as a recording agent, and the dyes include (a) C-1-(Color Index) Direct Red 7S, C, 1, Direct Red and 3, C, 1, Direct red and 3:/
,C,1,Direct Red,2da0,C,I.

Acid Red/ / 9, C, 1, Acid Red/
/92/, C,1, Acid Red, 2/7, C,1,
Acid Red, 27 and C・■・Acid Red, 2
．． ．． 2.1! '-〇・■・Acid Red, 299 and C,1, Acid Red 3.2 (hereinafter (a)
) group and abbreviated) and (b) C, 1, Direct Red and 2, C, 1, Direct Red 72, C.
,1,Direct Red θ,C,1,Direct Red and/,C,1,Direct Red 29,C,1,Acid Red and,C,1,Acid Red3. ffj,C
,1, Acid Red 36 Otsu, C,1, Acid Red 337, C,1, Acid Red 2, C,1, Acid Red j7, C,1, Acid Red /j/, C,1
, Acid Red/j, and seven or more selected from the group consisting of C,1, Acid Red, and 2j2 (hereinafter abbreviated as group (b)).

According to the present invention, the viscosity, surface tension, etc. are within appropriate ranges,
It does not clog the fine orifice, provides recorded images with sufficiently high density, does not cause changes in physical properties or precipitation of solids during storage, and can record on various materials without limiting the type of recording material. It is possible to obtain a recording liquid that provides images with high fixing speed, excellent water resistance, abrasion resistance, and resolution.

The dyes of group (a) used as the recording agent of the present invention are all excellent in the above-mentioned important properties as a recording agent, such as solubility and light resistance, but in terms of color tone, they are all slightly violet. Since these dyes exhibit a slightly magenta color, these dyes alone are not suitable as recording agents for recording liquids for the magenta primary color. On the other hand, group (b) dyes are also excellent in other properties except for color tone, but on the contrary, they exhibit a slightly orange magenta color, so they are similarly not suitable as recording agents for recording liquids. It's not appropriate. therefore,
In the present invention, by using one or more dyes of group (a) and one or more dyes of group (b), it has an ideal color tone as a magenta primary color, and has important properties such as solubility and light fastness. A recording liquid containing a recording agent with excellent properties was obtained.

The content of these color components in the recording liquid, that is, the total dye content of groups (a) and (b), is determined depending on the type of liquid medium components, the characteristics required of the recording liquid, etc. Generally, θj-, 20 weight ratio, preferably 9
The range is 5 to 75% by weight, more preferably 10 to 10% by weight.

In addition, the blending ratio of the seven or more dyes selected from group (a) and the seven or more dyes selected from group (b) at this time is as follows:
Since the hue exhibited by the dyes in each dye group differs depending on the individual dyes, the optimal value is determined for each combination of selections, but generally it is selected in the range of /:2 to 9:/.

The recording liquid of the present invention has water as a main liquid medium component, but not only water alone but also preferably a mixture of water and various water-soluble organic solvents is used. Examples of water-soluble organic solvents include alkyl alcohols with a carbon number of ~g, such as methyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, 5eC-butyl alcohol, tert-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 and propylene glycol , butylene glycol, triethylene glycol, /:c2゜-hexanetriol, thiodiglycol, hexylene glycol, diethylene glycol, and other alkylene glycols in which the alkylene group has 2 to 2 carbon atoms: glycerin: ethylene glycol Examples include lower alkyl ethers of polyhydric alcohols such as recall methyl ether, diethylene glycol methyl (or ethyl) ether, and triethylene glycol monomethyl (or ethyl) ether.

Among these many water-soluble organic solvents, polyhydric alcohols such as diethylene glycol and lower alkyl ethers of polyhydric alcohols such as triethylene glycol monomethyl (or ethyl) ether are preferred. Polyhydric alcohols are particularly preferred because they are highly effective as wetting agents to prevent nozzle clogging caused by evaporation of water in the recording liquid and precipitation of the recording agent.

The content of the water-soluble organic solvent in the recording liquid is generally in the range of 5 to 25% by weight, preferably /θ~0%, and more preferably 20 to 50% based on the total weight of the recording liquid. It is said that

The water content at this time is determined within a wide range depending on the type of solvent component, its composition, and the desired characteristics of the recording liquid, but it is generally 70 to 90% of the total weight of the recording liquid.
, preferably /θ to 7θ, more preferably 20 to 7
It is assumed to be within the range of θ.

A solubilizer can also be added to the recording liquid of the present invention. Typical solubilizing agents are nitrogen-containing heterocyclic ketones, and their intended action is to dramatically improve the solubility of recording agents in liquid media. For example, N-methyl-3
-pyrrolidone, X3-dimethyl-2-imidazolidinone, etc. are preferably used.

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) The storage stability, fixing properties to recording materials, and the light resistance, weather resistance, and water resistance of recorded images are all well-balanced and excellent. In order to further improve such properties, various conventionally known additives may be added.

Examples: Viscosity modifiers such as Eva, polyhinyl alcohol, celluloses, and water-repellent resins; Various cationic, anionic, or nonionic surfactants; Surface tension modifiers such as diethanolamine and triethanolamine; PH modifiers using buffer solutions etc. can be mentioned.

Further, in order to prepare a recording liquid used in an inkjet recording method in which the entire 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.

The recording liquid of the present invention has particularly excellent properties as a recording liquid for inkjet recording, but it can also be used for recording with conventional writing instruments such as fountain pens and felt-tip pens that record on recording materials such as paper. It can also be used as a liquid.

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

Example/ A magenta primary color recording liquid for inkjet recording was prepared according to the following formulation.

C・■・Acid Red/ / 9. 2.0 weight ratio C, 1, acid red/S and 30
〃Diethylene glycol 3θ0 〃N-methyl-2-pyrrolidone /jθ 〃Ion exchange water
Remaining Amount The above-mentioned ingredients were stirred in a container, mixed and dissolved uniformly, and then filtered through a Fluorobor filter with a pore diameter of θgjμ, and further deaerated to obtain a recording liquid. , an on-demand inkjet recording head that ejects with a piezoelectric vibrator (discharge orifice diameter 50 μ, piezoelectric vibrator drive voltage O 0, frequency 'I K
The ejection stability was evaluated using a recording device having a high speed (Hz). As a result, room temperature (,2/℃), 5℃,
9 each in an atmosphere of 0°C and 0°C (humidity 3θ)! Good ejection stability was maintained in both continuous ejection for 2 hours and intermittent ejection for 2 q hours.

On the other hand, the long-term storage stability of the recording liquid was investigated at 0°C, 30°C,
Testing was carried out at θ°C for 3 years each, but no problems such as recording agent precipitation or discoloration occurred.

The color tone of the printed matter was a clear, bright, and ideal magenta color, and the printed matter was sufficiently legible even after a 30-hour irradiation test using a xenon fade meter, and its light resistance was also good.

Example ρ A magenta primary color recording liquid based on the following formulation was prepared in the same manner as in Example.

C・Engineering・Acid Red...! 99 1
0 weight i%C, 1, acid red 3. S, S
,,20 〃Diethylene glycol
/bu0 〃/,3-dimethyl=! -Imidazolidinone /,! ;0 Polyethylene glycol (3
00) /i0 //ion exchange water
Remaining Amount On the other hand, a yellow primary color recording liquid, a cyan primary color recording liquid, and a plaque recording liquid were prepared in the same manner as above.

However, instead of C, 1, Acid Red 292 and C・■, Acid Red J, f5, C, 1, Acid Yellow, 23 All is used for the yellow primary color recording liquid, and C, 1, Direct Blue and B are used for the cyan primary color recording liquid. In the case of a plaque recording liquid, 3 parts by weight of each of C.1 and Direct Plaque/9 were blended.

On-demand type multi-head (discharge orifice diameter 3Sμ, heating resistor resistance value/SθΩ, drive voltage 30V, Frequency, 2KH
z) 'Fr: All color printing tests were conducted by supplying the sample to a recording device with the following. Regarding the ejection stability, stable ejection was maintained in all cases under the same conditions as in Examples. ′! f,
In addition, the obtained images were also full-color images in which predetermined color tones were expressed, and it was evaluated that each recording liquid was excellent as a primary color liquid for subtractive color mixing. Furthermore, the print was still legible even after the same light fastness test as in Example.

Example 3~/Otsu C, 1, Acid Red // 9 and C, 1, Acid Red 7.5f were replaced with the dyes shown in Table -/ and the amounts thereof were used in the same manner as in Example/. A magenta primary color recording liquid was prepared. These recording liquids were evaluated for ejection stability, long-term storage stability, color tone of printed matter, and light resistance in the same manner as in Examples (all of them were good, and they were excellent as recording liquids for magenta primary color. It turned out that

Table - / Note) A, R, C9■, Acid Red, D, RH
C.I.

Patent applicant featuring Direct Red Canon Co., Ltd. Procedural Amendment 1, Case Indication 1962 Patent Application No. 731.3'
No. 17 No. 2, Recording liquid for the name of the invention 3, Relationship with the case of the person making the amendment Applicant (/00) Canon Co., Ltd. 4, Date sent by agent for amendment order 1] July 30, 1980 Amendment B Column 7 in the table of the subject specification and the table of contents of the amendment on pages 1S to 1B of the specification are amended as shown in the attached sheet.

The quality, color tone of printed matter, and light fastness were evaluated, and all were found to be good, indicating that the liquid was excellent as a recording liquid for magenta primary color.

Table - / Note) A, R is C, 1, acid red, D, R is C, I.

Featuring direct red Patent applicant: Canon Co., Ltd. Agent Tadashi Wakabayashi

Claims (1)

[Claims] (a) C0■, Direct Red 75,
C,1,Direct Red and 3,C,1,Direct Red and 3:/,C,1,Direct Red,211θ,
C, 1, Acid Red // 9, C, 1, Acid Red // 9: /, C, 1, Acid Red 277
, C,1, Acid Red, 27, C,1, Acid Red, 22g, C,1, Acid Red 29, and C,1, Acid Red 3,2F. ,(b)C,1,Direct Red and 2
,C,1,Direct Red 79,C,1,Direct Red and θ,C,1,Direct Red Za/,C0■,
Direct Red 91, C, 1, Acid Red and C
, 1, Acid Red J, f5-. C,1, Acid Red 3 Otsu, C,1, Acid Red 337゛C,1,
acid red”a, 2, c, 1, acid red j7
,C,1,Acid Red/3/,C,1,Acid Red/,S! and C, 1, acid red, 2. ff,
A recording liquid characterized in that it is used in combination with 7 or more types selected from the group consisting of 2.