JPH0229470A - Recording fluid - Google Patents

Abstract

PURPOSE:To obtain a quick-drying ink which does not cause degradation of a recorded image such as blotting of a recorded image by adding a polyalcohol, a specified water-soluble medium and a specified compound to a recording fluid based on a water-soluble dye, a water-soluble solvent and water. CONSTITUTION:A polyalcohol (e.g., ethylene glycol) as a wetting agent and at least one water-soluble medium for improving the speed of penetration of an ink into paper, selected from among a polyalcohol alkyl ether, a polyalcohol aryl ether and a fluorinated surfactant (e.g., diethylene glycol monobutyl ether) is added to a recording fluid based on a water-soluble dye, a water-soluble solvent and water, and a compound of the formula (wherein R is a 10-12 C aliphatic hydrocarbon group) is added to the mixture to prevent blotting of an image. In this way, a water-base ink for an ink jet printer, which does not cause degradation of an image, such as blotting of a recorded image, can be obtained.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an inkjet printer, particularly a multicolor printer,
Regarding water-based ink for inkjet printers, it is also used as water-based ink for recorders, pen plotters, and writing.

[Prior Art] Various inks have been proposed in the past. However, in order to prevent nozzle clogging and provide long-term storage stability, highly soluble dyes must be used. However, images formed with highly soluble dyes tend to have poor water resistance.

In particular, it is difficult to improve the water resistance of color inks with vivid colors. In addition, for high-speed recording, it is necessary to have quick drying properties.

Conventionally, recording liquids containing water-soluble organic solvents or surfactants have been used in Japanese Patent Application Laid-Open No. 47-12104 to provide quick drying properties.
No., JP-A-49-97620, JP-A-55-1604
No. 2, Japanese Unexamined Patent Publication No. 55-29548, etc., but these have the drawback of causing blurring and deterioration of resolution.

Additionally, methods of dissolving the sizing agent by adding a base are disclosed in JP-A-47-12105, JP-A-53-11606, JP-A-53-135707, and JP-A-56-57862.
JP-A-56-57862, JP-A-56-133378
, JP-A-58-2384, JP-A-58-125787
However, the drying properties of these two-color overlapping areas are insufficient. In addition, in order to further improve these, the addition of various additives has been considered, but at present no satisfactory results have been obtained.

[Problems to be Solved by the Invention] The present invention aims to provide an ink for an inkjet printer, particularly an inkjet printer capable of recording in multiple colors, and a quick-drying ink that does not cause image deterioration such as bleeding of recorded images. It is.

[Means for Solving the Problems] The structure of the present invention for solving the above problems is such that a recording liquid mainly containing a water-soluble dye, a water-soluble solvent, and water contains polyhydric alcohol and polyhydric alcohol alkyl ether. , a recording liquid characterized by containing one or more of polyhydric alcohol aryl ether and fluorosurfactant, and further containing a compound represented by the following - Murder I, General formula I, where R: carbon These are several 10 to 12 aliphatic hydrocarbon groups.

The compound represented by Murder I above is a component that prevents blurring of images. The content of this compound in the ink is 3~
30wt% is appropriate, more preferably 5-20wt
%.

This compound of Murder I is usually commercially available as an aqueous solution and has a solubility in water of 25-35%. These commercially available aqueous solutions contain inorganic salts as impurities, but if necessary, the inorganic salts can be removed using an ion exchange resin.

As the water-soluble dye of the present invention, any conventionally known acidic dye or direct dye having a sulfonic acid group or a carboxyl group and having high solubility can be used. The following dyes are listed as highly soluble dyes. The content of dye in the ink is 0.
5-20vt%, more preferably 1.5-6.0vt%
is appropriate. If it is less than 0.5 wt%, its effectiveness as a coloring agent will be weakened and the density of the resulting image will be insufficient, and if it exceeds 20 wt%, precipitates will form in the ink over a long period of time, making inkjet recording difficult. It tends to not be done correctly.

Black dye: C, +, acid black 1.2.7.2
4.26.94, C, 1, Direct Black 19.22.32.38.
51.56.71.74.75, 154, 168, C,
1, Food Black 2 Yellow Dye: C, 1, Acid Yellow 17.23.38
．． 42.79, C, 1, Direct Yellow 1.12.24.26,
27, 28, 44, 86, 50, 142, 144,
C,1, Food Yellow 4,3 Red, Magenta Dye: C,1, Acid Red, 118
, [8.27.35.37.42.80.82.83.
106, IIL 114, 115, 18B, 24
9.254, 265, 289 C, 1, Direct Red 9.20.80.8L 89
, 227 Blue, cyan dye: C,! , Acid Blue 9.29.
45.80.92, 185.249.254C11, Direct Blue 22.71.76.78.8G, 87.
90.98.106.158.163.165.202 C11, Food Blue 1.2 Even if these dyes interact with the amphoteric surfactant represented by the general formula (1) in the ink, the pH will be 7 or higher ( (above the isoelectric point), the dye does not precipitate and its solubility is not impaired, or when it adheres to the paper surface, it reacts with the acidic components in the paper and becomes an insoluble salt, which has excellent fixing properties and penetrates. It is estimated that it is possible to prevent 1ii4 quality deterioration such as feathering caused by the agent.

Polyhydric alcohols used as wetting agents include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol 200.30, 400.600, propylene glycol, dipropylene glycol, polypropylene glycol, glycerin, etc. High solubility,
This is the most preferred in terms of low evaporation rate and high equilibrium water content.

As a wetting agent other than polyhydric alcohol, N-methyl-2-
Pyrrolidone, 1,3-dimethylimidazolidinone, and triethanolamine are preferred, and can be used in combination with the above polyhydric alcohols.

The total amount of these wetting agents in the ink is 5 to 70 wL%, preferably 5 to 35 wL%, in 1 g or more.

In order to improve the penetration rate of the ink into paper as the water-soluble medium of the present invention, polyhydric alcohol alkyl ether, polyhydric alcohol allyl ether, and fluorine-based surfactant (
Add one kind of each.

Particularly preferred are diethylene glycol monobutyl ether, propylene glycol monobutyl ether, and diethylene glycol monophenyl ether as suitable additives that do not reduce dye solubility when added.

The amount of these polyhydric alcohol alkyl ether and polyhydric alcohol phenyl ether added to the ink is 2 to 25ν.
It is preferable to add t%, more preferably 5 to 15vt%.

Examples of the fluorosurfactant include perfluoroalkyl phosphates, perfluoroalkyl carboxylic acids, and perfluoroalkyl betaines. Addition amount is 10pp
m~200ppm, preferably 50ppm~1100
It is desirable to add pp.

In addition to the above-mentioned compounds, any conventionally known compounds can be added to the present invention as needed.

For example, as the preservative and fungicide, sodium dehydroacetate, sodium sorbate, sodium 2-pyridinethiol-1-oxide, sodium benzoate, sodium pentachlorophenol, etc. can be used in the present invention.

pH: Any material can be used as the plasticizer, as long as it does not adversely affect the ink being prepared and can control the pH of the ink.

Examples include amines such as jetanolamine and triethanolamine, lithium hydroxide, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, ammonium hydroxide, quaternary ammonium hydroxide, and quaternary phosphonium hydroxide. Examples include carbonates of alkali metals such as lithium carbonate, sodium carbonate, and potassium carbonate.

Examples of the chelating reagent include sodium ethylenediaminetetraacetate, sodium nitrilotriacetate, sodium hydroxyethylethylenediaminetriacetate, sodium diethylenetriaminepentaacetate, and sodium uramildiacetate.

Examples of rust preventives include acidic sulfites, sodium thiosulfate, ammonium thioglycolate, diisopropylammonium nitrite, pentaerythritol tetranitrate, and dicyclohexylammonium nitrite.

Other water-soluble ultraviolet absorbers, water-soluble infrared absorbers, and water-soluble polymer compounds depending on the purpose. A dye solubilizer, a surfactant, etc. can be added.

Examples and comparative examples of the present invention are shown below. All percentages are by weight.

Example 1 An ink was prepared by heating the following composition to about 50°C, stirring and dissolving it, and then filtering it through a Teflon filter with a pore size of 0.22 μm.

(Yellow ink Yl) C, 1, acid yellow 23 (desalted purified product) 3% 35% aqueous solution of R-C12 of general formula (I) (desalted purified product) 30% diethylene glycol 15% glycerin
5% diethylene glycol monobutyl ether 5% sodium dehydroacetate 0.3% lithium hydroxide 0.1% pure water
Remaining amount (magenta ink Ml) C, 1, Acid Red 254 (desalted purified product) 3% 35% aqueous solution of R-carbon number 12 of general formula (1) (desalted purified product) 30% Diethylene glycol 15% glycerin
5% diethylene glycol monobutyl ether 5% sodium dehydroacetate 0.3% lithium hydroxide 0.1% pure water
Remaining amount (cyan ink CI) C, 1, acid blue 249 (desalted purified product) - formula (
I) R-35% aqueous solution with 12 carbon atoms (desalted purified product) 3
0% diethylene glycol 15% glycerin
5% diethylene glycol monobutyl ether 5% sodium dehydroacetate 0.3% lithium hydroxide 0.1% pure water
Remaining amount (black ink BKI) C01, Food Black 2 (desalted purified product) - Formula (1)
35% aqueous solution of R-carbon number 12 (desalted purified product) 30% diethylene glycol 15% glycerin
5% Sodium diethylene glycol monobutyl ether dehydroacetate 03%
Sodium hydroxide 0.1% pure water
Remaining Amount Example 2 An ink having the following composition was obtained in the same manner as in Example 1.

(Yellow ink Y2) C, 1, Direct Yellow 8G (desalted purified product) 2.5
% R of general formula (1) - 25% aqueous solution with 10 carbon atoms (desalted purified product) 20% ethylene glycol 15% glycerin
5% propylene glycol monobutyl ether 5% sodium dehydroacetate 0.3% tetramethylammonium hydroxide (15% aqueous solution)
1% pure water
Remaining amount (Magenta ink M2) C11, Direct Red 9 (Desalted purified product) 3% 25% aqueous solution of general formula (I) R-carbon number 10 (Desalted purified product) 20% Ethylene glycol 15% Glycerin
5% propylene glycol monobutyl ether 5% sodium dehydroacetate 0.3% lithium hydroxide 0.1% pure water
Remaining amount (Cyan ink C2) C, 1, Direct Blue 199 (Desalted purified product) 25% aqueous solution of R-carbon number IO of general formula (I) (Desalted purified product) 20% Ethylene glycol 15% Glycerin
5% propylene glycol monobutyl ether 5% sodium dehydroacetate 0.3% tetramethylammonium hydroxide (15% aqueous solution)
1% pure water
Remaining amount (black ink BK2) C91, Direct Red 154 (desalted purified product) 3% 25% aqueous solution of R-carbon number 1O of general formula (1) (desalted purified product) 20% Ethylene glycol 15% glycerin
5% propylene glycol monobutyl ether 5% sodium dehydroacetate 0.3% tetramethylammonium hydroxide (15% aqueous solution)
1% pure water
Remaining Amount Comparative Example 1 Six color inks (Y3, Y3,
M3, C3, BK3) were produced.

Comparative Example 2 Ink of each color (Y4, Y4,
M4, C4, GK4) were produced.

Printing tests were conducted on the inks of the above Examples and Comparative Examples using a drop-on-demand inkjet printer with a nozzle diameter of 60 μm to perform multicolor printing in the patterns shown in FIGS. 1 and 2.

Figure 1 shows a completely solid adjacent pattern. FIG. 2 is a grid line pattern.

The evaluation items are as follows.

(1) Drying property After printing, the side image area was rubbed with a filter paper, and the time until ink transfer to the filter paper disappeared was measured.

(2) Image stain Image stain due to mist was visually determined.

O: Good, △: Fair, ×: Bad (3) Image blurring The degree of image quality due to blurring was visually judged.

○: Good, △2 Average, ×: Bad (4) Water resistance Macbeth? It was measured with an H degree meter, and the fading rate % was calculated using the following formula.

(5) Preservability Put the ink in a polyethylene container,
The samples were stored for 3 months at -20°C, 4°C, 20°C, 50°C, and 70°C, and the changes in viscosity, surface tension, and electrical conductivity before and after storage were examined, as well as the presence of precipitates. Ta. No matter what conditions the sample was stored under, it was rated as O if there were no changes in physical properties or generation of precipitates.

The printing paper used was commercially available high-quality paper (paper surface pH 4,0).
[Effects of the Invention] As described above, it is possible to provide a multicolor inkjet ink that improves drying properties and does not cause deterioration in resolution, and the inkjet printer can be used in color plotter printers for CAD/CAM and the like.

[Brief explanation of the drawing]

FIG. 1 shows a completely solid adjacent pattern of a multicolor print using the ink of the present invention, and FIG. 2 shows a grid line pattern as well. Y...Yellow, M...Magenta, C...Cyan, Bk...Black, R...Red, G...Green, B...Blue

Claims (1)

[Scope of Claims] A recording liquid mainly containing a water-soluble dye, a water-soluble solvent, and water, including a polyhydric alcohol, and one of polyhydric alcohol alkyl ethers, polyhydric alcohol aryl ethers, and fluorosurfactants. A recording liquid characterized by containing the above and further containing a compound represented by the following general formula I, General formula I ▲There are numerical formulas, chemical formulas, tables, etc.▼ However, R: a fat having 10 to 12 carbon atoms. group hydrocarbon group.