JPS63280781A - Recording liquid - Google Patents

Abstract

PURPOSE:To obtain a recording liquid, containing a water-soluble dye, aqueous medium, strong basic compound and water-soluble resin, having excellent quick- drying properties and printing quality after recording without causing shear of images even by rubbing printed parts and useful for ink jet recording and writing utensils. CONSTITUTION:The aimed recording liquid containing (A) preferably 2-8wt.% water-soluble dye (e.g. C.I. Direct Black-17), (B) preferably 20-89.5wt.% aqueous medium, (C) preferably 0.2-5wt.% strong basic compound (added for keeping pH at preferably 12-14, e.g. sodium hydroxide) and (D) preferably 0.5-2.5wt.% water-soluble resin (preferably water-soluble polyamide).

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a recording liquid for inkjet recording and writing instruments.

(Prior art) When plain paper such as electrophotographic paper, pound paper, stock form paper, etc. is used as the recording paper in an inkjet recording method, even if the recorded print is pinched with a finger after recording, image shift may occur. There have been problems with shortening the time required for the printing to stop occurring (quick drying properties), ensuring that the printed characters have clear outlines without bleeding (print quality), etc.

Conventionally, recording liquids containing specific water-soluble organic bath agents or surfactants (JP-A No. 4!?-/Ko 10'1, JP-A-1999-1993) have been used.
No. I9-97620, published by Tokukai Sho! r-/1. OII Ko issue, Tokukai Akira! f! R-29346 and other publications 2, recording liquids in which a base is added to the recording liquid (JP-A Shoda 7-/K10!r, JP-A Sho!r3-IIAOA, JP-A Shoj, 7- /3!
70'1, Tokukai ShojA-! ;7g4ko issue, Japanese Patent Application Publication No. 1973
-133376, JP-A-5T-1,7AII, JP-A-11-/KO-5767), a recording liquid containing a water-soluble resin added to the recording liquid (JP-A-1999-70-/7t4tO, JP-O However, these recording liquids may not have sufficient effects on the above-mentioned problems, or even if they are effective, they may not be effective. It also has a major defect in that the nozzle tip tends to become clogged.

(Problems to be Solved by the Invention) An object of the present invention is to provide a recording liquid that can obtain prints with quick drying properties and excellent print quality even when recording is performed on plain paper.

(Means for Solving the Problems) The gist of the present invention is a recording liquid containing a water-soluble dye, an aqueous medium, a strong basic compound, and a water-soluble resin.

Examples of the water-soluble dyes of the present invention include azo-based, anthraquinone-based, quinophthalone-based, indigo-based, and phthalocyanine-based direct dyes and dispersible dyes, such as C1 dye,
Direct Black -77, -ノ? , - here, -3,2, -5/, -10,12 de/, -/! /and-ts4t, a, engineering, DireCtBlue -1;
4 and -/9ri, C3 construction, Direct Red
-tro, a, engineering, Direct Yellow -
t A and -7 octopus, C0 engineering, AQid Black
-, 2, -12 Tei, -26, -Hiroza, -3ko, -63
, -/Kuyu, -/9 Hiro and -Kog, o, Ko, A(!
i(L Blue -9, -1g5 and -ko j41, C
1st, Ac1d Red -1, -, 7, t, -,
7'7 and --jri, C8 engineering, Ac1d Yellow
W-co3 and -data and C8, Food Black
Examples include k-ko.

The content of the above-mentioned water-soluble dye 'C is in the range of 0.3 to 2%, preferably in the range of co to g%, based on the total weight of the recording liquid.

In addition to water, the aqueous medium of the present invention includes, for example, ethylene glycol, flopylene glycol, butylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol/L/(medium 200), polyethylene glycol <+uoo), y Preferably, the aqueous medium contains lyserine, N-methyl-pyrrolidone, B-ethyl-pyrrolidone, ethylene glycol monoallyl ether, ethylene glycol monomethyl ether, diethylene glycol monomethyl ether, etc. For weight, ko0-t9. ! 11. ! % range is mentioned.

The strong basic compound of the present invention is added to keep the recording liquid basic, preferably at a pH of /- to /+, and specifically includes an alkali metal hydroxide or a strong nitrogen-containing organic base. chemical compounds are used.

As the alkali metal hydroxide, lithium hydroxide,
Examples include sodium hydroxide and potassium hydroxide.

Examples of the nitrogen-containing organic strong basic compound include c) IJ
Methyl-β-hydroxyethylammonium hydroxide, diethyl-di-β-hydroxypropylammonium hydroxide, butyl-triβ-hydroxyethylammonium hydroxide, trimethyl-β-hydroxybutylammonium hydroxide, trimethyl-β-ethoxy ether 9th class ammonium hydroxide such as ammonium hydroxide, guanidine such as tetramethylguanidine, tetra-β-hydroxyethylguanidine, diethyl-di-β-hydroxyprobylguanidine, tetramethylguanidine, tetra-β-hydroxy-butylbiguanidine, etc. derivative or diazabicycloundecene (hereinafter referred to as DBO)
), etc.

The amount of the strong basic compound to be used is in the range of 0.1 to 10% by weight, preferably 2 to 3M%, based on the total weight of the recording liquid.

The strong basic compounds mentioned above can be used alone or mixed together.

Water-soluble resins are added as recording liquids to prevent bleeding when printing, and include water-soluble polyamides, water-bathable cellulose, polyvinyl alcohol,
Polyvinylpyrrolidone, polyvinylamine, polyallylamine, etc. may be used.

Water-soluble polyamides include those in which the hydrogen atom of the amide group is replaced with a hydroxyalkyl group, alkoxyalkyl group, etc., or a pipolyalkylene glycol group, a goperazine ring, a furan ring, or an oxygen atom, a sulfur atom, etc. in the main chain of the polyamide. Examples include water-bathable modified polyamides into which heteroatoms have been introduced.

These modified polyamides include, for example, Corbyrolidone, ε
- Lactams such as caglolactam, δ-valerolactam, enantholactam, η-caglillactam, and ω-laurolactam, and polyethylene glycol (molecular weight 100~
Polyols such as 3θoO8 polypropylene glycol, polytetramethylene glycol, polybutadiene glycol, etc., and catalysts such as alkali metals, alkaline earth metals, hydroxides, oxides, and carbon rvl salts of the metals, and aliphatic bisacyllactams. It can be produced by anionic polymerization in the presence of an activator such as.

It can also be produced by copolymerization using a dicarboxylic acid containing a heterocycle or a heteroatom and a diamine, or by treating a polyamide homopolymer with formalin and alcohol to introduce an alkoxy group.

The water-soluble polyamide mentioned here has a melting point of 60 to ℃.
/30℃, glass transition point -to'~70℃, solubility in water! r-! fO weight%, furthermore, the viscosity of the aqueous solution measured by a B-type viscometer (-〇℃ temperature/0% water FF liquid Te, 2
o ~lIo cps, 750~. with 20% aqueous solution. 7
00 cps, 30% aqueous solution/300 ~ coooocp
s, IIo% aqueous solution too~/! 000 cp
Use one that exhibits basic characteristics such as s.

Specifically, examples include AQ-Nylon A-to (manufactured by Tit Shi Co., Ltd.) and AQ-Nylon P-70 (manufactured by Co., Ltd.).

In addition, water-soluble cellulose includes water-soluble cellulose conductors such as hydroxyethyl cellulose, hydroxyglobil cellulose, and methyl cellulose, or polyvinyl alcohol, polyvinylpyrrolidone, polyvinylamine,
Examples include polyallylamine.

The content of these water-soluble resins is preferably 0.3 to 5% by weight, preferably 5% by weight, based on the total weight of the recording liquid.

(Examples) The present invention will be explained in more detail using the following examples, but the present invention is not limited to the following examples.

Example/ Composition of recording liquid Usage amount (weight%) C1,
Direct Black -/! r 4t
J ethylene glycol monoallyl ether
λS ethylene glycol 22
Tetramethylguanidine lAQ, nylon A-qo (manufactured by Toshi Co., Ltd.) 7g
A total of 100 of the above components were thoroughly mixed and dissolved in a container, filtered under pressure through a Teflon filter with a pore size of lμ, and then degassed using a vacuum pump to prepare a recording liquid.

Using the obtained recording liquid, inkjet printer (
Inkjet recording was carried out using IP-/JOK, manufactured by Epson Corporation, and quick-drying properties and print quality were evaluated according to the methods described in (2) and (b) below.

(Quick drying: Print on electrophotographic paper (manufactured by Fuji Xerox Co., Ltd.), bond paper, and stock form paper (manufactured by Lion Office Equipment Co., Ltd.), and after 30 seconds rub the printed area with your finger to determine whether or not the image is misaligned. did.

All showed excellent fixing properties without any deviation.

(1)) Print quality: Each dot printed on the above-mentioned recording paper was observed under a microscope, and evaluated by visually observing the presence or absence of feathering (whisker-like blurring) around the dot and sharp visual inspection of ring marks.

There was no feathering in either case, and the outlines were sharp.

In addition, inkjet recording was evaluated according to the methods described in (f) below.

(C) Long-term storage stability of recording liquid: Even after recording liquid was sealed in a glass container and stored at -30°C and 60°C for 6 months, no precipitation of insoluble matter was observed, and there were no changes in the physical properties or color tone of the liquid. There was no.

(eL) Ejection stability: Continuous ejection was carried out for several hours in an atmosphere of room temperature, 3° C., and aO° C. Under all conditions, stable high-quality recording was possible from beginning to end.

(Discharge responsiveness) Intermittent discharge every second and discharge after being left unused for several months were investigated, and in both cases stable and uniform recording was achieved without clogging at the orifice tip.

(f) Quality of recorded image: The recorded image had high density and clarity. After three months of exposure to room light, the density reduction rate was less than 7%, and when immersed in water for 7 minutes, there was very little blurring of the image.

Comparative Example/-/ Recording g was prepared except for the tetramethylguanidine in Example/, and quick drying and printing quality were examined according to the method in Example/(b). As a result, image bleeding was observed. Although it was small and had a sharp outline, it took 3 minutes for it to stop shifting.

Comparative Example/-AQ in Example 1, -Nylon A-O (manufactured by Toshi Co., Ltd.)! J: Prepare a recording liquid by removing
) and (1)), the quick-drying properties and print quality were examined. As a result, the image did not shift after 30 seconds, but the dots were significantly smeared in the horizontal direction and their outlines were blurred.

Comparative Example/-3 Triethanolamine was used instead of tetramethylguanidine in Example 1, and a recording liquid was prepared except for AQ and nylon A-90, and quick-drying was performed according to the method of (2) and (b) of Example 1. As a result of examining the printing quality, the results showed that there was no image shift within minutes, but the dots were bleeding in the horizontal direction and the outlines were blurred.

Composition of recording liquid used in Example 1 (wt%)
Direct Black-1y
J Glycerin i.

Ethylene glycol 10 Potassium hydroxide O, Hydroxypropylcellulose 0.75 Water
Total leftover meals
A recording liquid having the above composition was prepared in the same manner as in Example 100, and as a result of examining (L) to (f), good results were obtained in all cases.

Comparative Example Co. The recording liquid was prepared by removing the hydroxypropyl cellulose in Example Co., and an investigation was conducted according to the method in (1) of Example 1. As a result, the image did not shift after 30 seconds. , there is significant feathering and bleeding around the dots.

Examples 3 to 41 According to the method of Example//, records e,'? were prepared and evaluated according to the methods (s) to (f), and all were found to be good.

Table 1 Example/S Water-soluble dye: C1, Direct Black
k-! r /or 19/, O, 工, Direct
Blue-g 4, C1 engineering, Direct Ye
low -1i42, C1 engineering, Ac1d Elacl
r-ko6 or -63, C0 engineering, AOI Blue
A recording liquid was prepared according to the method described in Example 1, except that -T, C0, Ac1d Re (1-f or -J7) was used alone, and the same procedure as in Example (S~(f)
We examined the following. Good results were obtained in both cases.

Example 16 O, X, Direct Black as water-soluble dyes
k −g O or -1si%c, Eng, Direc
tRed-10.

C, 1, Ac1d Black -41g, -5 pieces, -
/7 ko, -/ 941 or -ko or, a, 工, Ac
14 Blue - Ko5da, C2 engineering, ACl (L R
ed-J! tri or C0 engineering.

A recording liquid was prepared according to the method described in Example J, except that Ac1d Yellow-II 't was used alone, and the same study as in Example 1 (S~(f)) was conducted. Good results were obtained in all cases. I got it.

(Effects of the Invention) The recording liquid of the present invention is used for inkjet recording, writing instruments, etc., and has excellent quick drying properties and print quality after recording, so even when recording on plain paper, the printed part can be touched with a finger. Even when rubbed, the image does not shift, and it is possible to obtain an image with sharp outlines without bleeding.

Also, inkjet recording using the recording liquid of the present invention.

In addition to the above-mentioned effects, when used for Water resistance etc. are all good.

Claims (9)

[Claims] (1) A recording liquid characterized by containing a water-soluble dye, an aqueous medium, a strong basic compound, and a water-soluble resin. (2) The recording liquid according to claim 1, wherein the strong basic compound is an alkali metal hydroxide. (3) The recording liquid according to claim 1, wherein the strong basic compound is a nitrogen-containing organic compound. (4) The recording liquid according to claim 1, wherein the water-soluble resin is a water-soluble polyamide. (5) The recording liquid according to claim 1, wherein the water-soluble resin is water-soluble cellulose. (6) The recording liquid according to claim 1, wherein the water-soluble resin is polyvinyl alcohol, polyvinylpyrrolidone, polyvinylamine, or polyallylamine. (7) The recording liquid according to claim 1, wherein the content of the strong basic compound is in the range of 0.2 to 3% by weight based on the total weight of the recording liquid. (8) The recording liquid according to claim 1, wherein the content of the water-soluble resin is in the range of 0.5 to 5% by weight based on the total weight of the recording liquid. (9) The recording liquid according to claim 1, wherein the recording liquid has a pH of 12 to 14.