JPH02147672A - Water-based ink composition - Google Patents

Abstract

PURPOSE:To obtain the title composition prevented from changes in a concentration with the lapse of time by mixing a water-based ink with a specified propionylamine compound as a hygroscopic agent. CONSTITUTION:At most 70wt.%, based on the total ink weight, hygroscopic agent comprising a propionylamine compound of the formula [wherein R1 is (CH2CH2O)nH, R2 is (CH2CH2O)mH; and n and m are integers] (e.g. propionylamine) is mixed with a colorant such as a water-soluble dye (e.g. acid dye, a direct dye or a basic dye) or a pigment (e.g. carbon black), water and optionally a water-soluble organic solvent (e.g. glycerol), a rust inhibitor, a surfactant, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an aqueous ink composition suitable for use in writing instruments, stamps, printing, recorders, and the like.

[Prior Art] Water-based ink contains at least one colorant and water as main components. On the other hand, 1. For example, fiber pens, felt pens,
There is a demand for inks with excellent drying resistance for various writing instruments such as resin pen nibs and fountain pens. This is so that the pen can be used even during storage or when the cap is removed from the writing instrument body and the pen tip is exposed to the atmosphere for a long time.

In contrast, it is known to use hygroscopic agents such as formamide and dimethylformamide. The idea is to absorb moisture from the air to compensate for the drying process.

[Problems to be Solved by the Invention] Various moisture absorbents other than those described above are known, but they also have drawbacks.

For example, the above-mentioned ink has the disadvantage that it is affected by humidity, that is, the density of the ink as a whole gradually decreases when exposed to high humidity conditions.

Therefore, an object of the present invention is to provide an ink composition that suppresses changes in ink concentration over time by using a moisture absorbent that is not easily affected by humidity.

[Means for Solving the Problems] A propionylamine compound represented by the following general formula (]) is used as a moisture absorbent. That is, the present invention provides a water-based ink composition containing at least a colorant and water as main components, which contains a propionylamine compound represented by the following general formula (1) as a moisture absorbent. The gist is:

During the ceremony Next, each component will be explained in detail.

First, the propionylamine compounds represented by the general formula (1) are propionylamine (when n and m are O), propionylethanolamine (when one of n and nl is O5 and the other is 1), propionylgetanol Amine (
For example, when n and m are both 1), it is used for writing instruments. For low viscosity ink, n
, m are preferably 30 or less, and their use is preferably 70% by weight or less based on the total amount of ink.

As the coloring agent, water-soluble dyes (for example, acid dyes, direct dyes, basic dyes) and pigments can be used.

To give specific examples, examples of acidic dyes include Eiseneosin GH (C, 1,45380) (manufactured by Hodogaya Chemical Industry Co., Ltd.) and Nigrosin NB conc (C.

1.50420) (manufactured by Susumu Kagaku Kogyo i%l), Water Black #2-1 (c, 1.15985°4209)
0.4.2745 mixed dye), water blue #9
(C, 1, 42090), Water Pink #2
(C, 1,45410) (Above 1, manufactured by Orient Chemical Industry ■), Kayafta-1 ~ Radin (C, 1, 19140)
(manufactured by Nippon Kayaku ■), etc. Direct dyes include Water Black #100 (C, 1, 35255) (
Direct Deep Black EX (C, 1,30235) (manufactured by Nippon Kayaku), Direct Deep Black XA (manufactured by Sumitomo Chemical) Direct Fast Black QOnQ (C, 1,277)
20) (manufactured by Hodogaya Chemical Industry ■), etc., and basic dyes include Eisen Victoria Blue BA (C, 1, 4,
4045) (manufactured by Hodogaya Chemical Industry Co., Ltd.), Methyl Violet FN (C.

1.42535) (manufactured by BASF, West Germany), Rhodamine 6GCP (C, 1,45160) (manufactured by Sumitomo Chemical Co., Ltd.), etc. Pigments include carbon black, phthalocyanine blue (c, r.

74160), Phthalocyanine Green (C.

1.74260), Hansa Yellow 30 (C, I.

11670), Disazo Yellow GR (C, 1, 2110)
0), Permanent Red 4R (C, I.

12335), Brilliant Carmine 6B (C.

1.15850),'Irsu')UdryRedCC,l
-46500), and these colorants can be used alone or in combination of two or more.

Here, when a pigment is used as at least a part of a coloring agent, it is desirable to use a dispersant in combination, as is well known.

As a dispersant, a polymeric dispersant or a surfactant can be used. Examples of the polymeric dispersant include natural rubbers such as gum arabic and gum tragacanth, glucosides such as saponin, methylcellulose, carboxycellulose, and hydroxyl. Cellulose derivatives such as methyl cellulose, lignin sulfonates, natural polymers such as shellac, polyacrylates, salts of styrene-acrylic acid copolymers, salts of vinylnaphthalene-acrylic acid copolymers, styrene-maleic acid copolymers salts of vinylnaphthalene-maleic acid copolymers, sodium salts of β-naphthalene sulfonic acid formalin condensates, anionic polymers such as phosphates, and nonionic polymers such as polyvinyl alcohol, polyvinylpyrrolidone, and polyethylene glycol. In addition, surfactants include anionic surfactants such as fatty acid salts, higher alcohol sulfate ester salts, alkylaryl sulfonates, polyoxyethylene alkyl ethers, polyoxyethylene alkyl esters, There are nonionic surfactants such as sorbitan alkyl esters and polyoxyethylene sorbitan alkyl esters, and these can be used alone or in combination of two or more.

Although water is used as a solvent, water-soluble organic solvents such as glycol, glycol ether, glycol ether ester, glycerin, pyrrolidone, and sorbitan can also be used in combination, if necessary.

In addition to the above ingredients, 1,2-benzisothiazoline-3
Antiseptic and antifungal agents such as -one, pentachlorophenol, and cresol, rust inhibitors such as benzotriazole, and various surfactants for adjusting surface tension can be used as appropriate.

The water-based ink of the present invention can be easily obtained by, for example, dissolving the above-mentioned components using a stirrer, or mixing and dispersing them using a dispersing machine such as a ball mill or a sand mill.

[Production use] The water-based ink composition of the present invention has good drying resistance.

Furthermore, the decrease in ink concentration is also suppressed.The reason why such an ink composition is possible is not certain, but it is speculated as follows.

The oxygen in the propionylamine compound shown in general formula (1) and the hydrogen in the water in the air are absorbed by hydrogen bonds, but the hydrogen bond strength is weakened due to the hydrophobic action of the propionyl group. This results in an appropriate amount of water absorption.

[Example] Hereinafter, "1 part" refers to "part by weight." Also,
The propionylamine compound represented by the general formula (]) is simply referred to as "compound <1>", and the numbers n and m are shown in parentheses.

(C, I, 15985.42090.42745
7 TO part mixed dye: Orient Chemical Industry Co., Ltd.) Ethylene glycol 10.0 parts Compound <
1> (0,1) 20.0 parts 1.2-benzisothiazoline 0.4 parts-3-one (preservative) Water 62.
6 parts Each of the above components was stirred for 1 hour using a stirrer to obtain a black ink.

A black ink was obtained in the same manner as in Example 1 except that ethylene glycol was used in place of the compound <1> (0,1).

Large difference Mλ Eiseneosin GH 5゜0 parts Ethylene glycol 5.0 parts Compound <
1> (1,1) 65.0 parts Scorenol S-9000, 4 parts (surfactant: manufactured by Kao ■) Water 24.
6 parts Each of the above components was stirred for 30 minutes using a stirrer to obtain a red ink.

A red ink was obtained in the same manner as in Example 2, except that formamide was used in place of the compound <1> (1,1).

Carbon black 5.0 parts Water black R510 2.0 parts (C, 1,50420) Styrene acrylic acid 2.0 parts Ammonium salt Glycerin 15.0 parts Compound <1
> (0,1) 45.0 parts Neugen P (
Surfactant, 0.05 part (manufactured by Dai-Kogyo Seiyaku ■) Water 30.
After dispersing 95 parts of each of the above components in a sand mill for 2 hours.

Coarse particles were removed by centrifugation to obtain black ink.

In Example 3, compounds <1. > Except for (0, 1), the amount of water was increased accordingly, all Example 3
A black ink was obtained in the same manner as above.

Disappointed Solitary Phthalocyanine Blue (C, 1,74160) 7.
0 parts styrene acrylic acid 2.0 parts ammonium salt compound <1> (1,2) 40.0 parts Neugen P (surfactant) 0.2 parts benzotriazole (rust inhibitor) 0.5 parts water
After dispersing 49.1 parts of each of the above components in a sand mill for 2 hours, coarse particles were removed in a centrifuge to obtain a blue ink.

Blue ink was obtained in the same manner as in Example 4, except that ethylene glycol was used instead of compound <1> (1,2).

Suitable for dogs Water Blue #9 5.0 parts Ethylene glycol 15.0 parts Compound <1> (5
,10) 15.0 parts Neugen P (surfactant)
0.1 part water
64.9 parts The above components were stirred for 1 hour using a stirrer to obtain a blue ink.

In Example 5, compound <1> (5, 10) was excluded, and the amount of water was increased accordingly.
Blue ink was obtained in the same manner as above.

Futan phthalocyanine green on the back 7.0 parts shellac
5.0 parts Sodium hydroxide
0.7 parts Compound <1> (40,40)
20.0 parts diethylene glycol 10
．． 0 parts water
57.3 parts The above components were stirred in a ball mill for 10 hours, and coarse particles were removed in a centrifugal separator to obtain a green ink.

A green ink was obtained in the same manner as in Example 6, except that Compound <1> (40,40) was removed and the amount of diethylene glycol was increased accordingly.

Spotless pruning permanent red 4 R (C, 1, 12335) 7
, 0 parts Styrene acrylic acid 3.0 parts Ammonium salt compound <1> (0,O) 6.0 parts Ethylene glycol 10.0 parts Sorbitan 10.0 parts Scorenol S -
9000, 3 parts water 63.
After dispersing 7 parts of each of the above components in a sand mill for 4 hours.

Coarse particles were removed using a centrifuge to obtain red ink.

In Example 7, a red ink was obtained in the same manner as in Example 7 except that the compound <1> (0,0) was removed and the amount of water was increased accordingly.

JDLL Water Pink #2 (C, 1,45410) 5
, O part compound <1> (1,O) 7
5.0 parts Neugen P (surfactant) 0.1 part water 19.
9 parts Each of the above components was stirred for 0.5 hour using a stirrer to obtain a red ink.

A red ink was obtained in the same manner as in Example 8, except that the compound <1> (1,O) was removed and the amount of water was increased accordingly.

Disaster Ban Yu Water Blue #9 6.0 copies (C, 1,
42090) Compound <1> (0,1) 20.0 parts Compound (1> (5,15) 15.0 parts Scorenol S-9000, 3 parts 1,2-benzisothiazoline 0.4 parts-3-one (Preservative) Water 58, 4z The above components were stirred for 1 hour using a stirrer to obtain a blue ink.

In Example 9, except for compound <1> (1,O) and compound (1) (5,15), ethylene glycol 20
．． All the same as Example 9 except that 0 parts and 15.0 parts of water were increased.
Blue ink was obtained in the same manner as above.

Permanent red 4 R (C, I, 12335) 7
, 0 parts Styrene acrylic acid 3.0 parts Ammonium salt compound <1> (0,l) 70.0 parts Ethylene glycol 10.0 parts Water
After dispersing 10.0 parts of each of the above components in a sand mill for 3 hours.

Coarse particles were removed by centrifugation to obtain red ink.

Red ink was obtained in the same manner as in Example 1o except that the compound <1> (0,1) was removed and the amount of ethylene glycol was increased accordingly.

[effect] Regarding those obtained in Examples and Comparative Examples 1 to 9.

The main body of a commercially available writing instrument having a fiber nib was filled with the ink, the cap was removed, and the following test was conducted. The results are shown in Table-1.

Test 1: Drying test Under conditions of temperature 20℃ and humidity 65% I left it alone and checked the number of times it could be written.

Test 2: Ink density reduction test Under conditions of temperature 20℃ and humidity 90% After leaving it for 20 days, the handwriting was written.

Visually check the density of handwriting before leaving it I guessed it.

(Hereinafter, blank space) Table 1 Furthermore, regarding those obtained in Example 10 and Comparative Example 10,
The ink was filled into a commercially available coating stamp stand (used by the user to apply ink at the time of use), and the following tests were conducted. The results are shown in Table 2.

Test 3: Drying test Under conditions of temperature 20℃ and humidity 65% Wooden before and after being left for 20 days Density of stamp imprinted using a seal The difference was visually observed.

Test 2: Ink density reduction test Under conditions of temperature 20℃ and humidity 90% Wooden before and after leaving for 20 days Density of stamp imprinted using a seal The difference was visually observed.

(Hereafter, margin) Table-2 in this way.

The water-based ink composition of the present invention includes: Difficult to dry, Also, Ink under high humidity It is also difficult to reduce the concentration.

Claims (1)

[Scope of Claims] A water-based ink composition comprising at least a colorant and water as main components, which contains a propionylamine compound represented by the following general formula (1) as a moisture absorbent. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (1) In the formula (R_1 represents (CH_2CH_2O)_nH R_2 represents (CH_2CH_2O)_mH (n and m are integers).)