JPH0819363B2 - Water resistant ink composition and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial application] The present invention relates to a water-based ink composition. More specifically, it has excellent water resistance on paper and stability over time as an ink for writing instruments, plotter pens, and ink jet printers. And an aqueous ink composition having the same.

[Prior Art and Problems to be Solved by the Present Invention] Various researches and developments have been conventionally performed for the purpose of imparting water resistance to handwriting on paper. A pigment-based water-based ink using a pigment is generally well known, but this pigment-based water-based ink has a problem in stability over time such as difficulty in dispersion stability and sedimentation of pigment particles.

[Means for Solving the Problems] In order to solve such problems, the present inventors use a so-called dye system having good water resistance on paper using a water-soluble dye that is superior in stability over time as compared with a pigment. Studies on aqueous ink compositions were conducted.

For ease of understanding, each component will be described with reference numerals (A) to (D) described in the claims.

The present inventors contain both a lipophilic group selected from an aromatic ring or an aliphatic hydrocarbon having a C number of 6 to 12 and a hydrophilic group selected from a group having at least one O, N or S atom. It has been found that the anionic dye ink containing a poorly water-soluble compound has a markedly improved water resistance on paper.

However, the above-mentioned compounds are poorly soluble in water and only a dispersion type ink can be obtained. By the way, among the above compounds, only the compound having a solubility of 5% by weight or more in ethyl alcohol at 20 ° C. has a surface tension of 60 dyn / cm at 20 ° C. when dissolved in 0.1% by weight of water as the component (B). The following new findings were obtained that the following anionic dyes are extremely suitably solubilized in water.

Based on this new finding, the present inventor has invented a water-based ink having excellent water resistance on paper and stability over time.

This is the invention of Japanese Patent Application No. 1-277313 made earlier by the present inventor. Although the present invention is excellent in water resistance and stability over time, the dye (B) is limited in the type of color and is somewhat unsatisfactory in color tone.

The present inventor further researched that the amount of the (B) dye was 0.5 to 30% by weight in the ink composition and 15% in the total weight of the dye.
By the above, it was found that even if an anionic dye having a surface tension of 0.1% by weight dissolved in water (D) above 60 dyn / cm at 20 ° C. is used, water resistance and stability over time are not deteriorated. And completed the present invention. The dye (D) cannot form a water-resistant ink by itself, but since it has many kinds of colors, it has an effect that the color tone can be adjusted well.

That is, the present invention relates to "1. Amount of 0.5 to 30% by weight in (A) water and (B) ink composition, and 15% by weight or more in the total weight of dye in the ink, and 0.1% by weight in water.
Anionic dye having a surface tension of 60 dyn / cm or less at 20 ° C. when dissolved and (C) an aromatic ring or a C 6-12 dendritic hydrocarbon as a lipophilic group, and O, N, S atoms Is a poorly water-soluble compound containing at least one of the above groups as a hydrophilic group and one or more of each of these groups, and the solubility when the compound is dissolved in ethyl alcohol is 5% by weight or more at 20 ° C. An anion having a surface tension of more than 60 dyn / cm at 20 ° C. when dissolved in water (D) in an amount of 0.1% by weight as a color tone adjusting agent in an ink composition prepared by dissolving a water resistance-imparting agent containing a compound as an effective component. A water resistant ink composition containing a type dye.

2. The water resistance imparting component (C) is 0.5 to 0.5 in the ink composition.
The water-resistant ink composition according to claim 1, which is 5% by weight.

3. Add the anionic dye of (B) and the anionic dye of (D) to the water of (A) to dissolve them completely, then add the water resistance-imparting agent of (C) at room temperature or higher. A method for producing a water-resistant ink composition, which comprises stirring and then adding and mixing the remaining components. ".

An alkylene group is preferable as the aliphatic hydrocarbon group of the water resistance-imparting agent.

[Operation] Regarding the improvement of water resistance on paper, the present inventor considers as follows from the fact that the present invention has reproducibility, although the elucidation by science is not always sufficient. That is, there is a poorly water-soluble compound containing an aliphatic hydrocarbon having a carbon number of 6 to 12 as a lipophilic group and containing at least one hydrophilic group having at least one O, N, or S atom having high electronegativity. Is stronger than the conventional hydrogen bond between paper and dye,
It is considered that a hydrogen bond is formed between the paper, the dye, and the poorly water-soluble compound, and the hydrophobicity of the poorly water-soluble compound improves the water resistance of the ink on paper.

Further, regarding the solubilization of a poorly water-soluble compound in water, the above-mentioned (B) anionic dye, especially a dye having a surface tension of 60 dyn / cm or less at 20 ° C. when dissolved in water of 0.1% by weight is micellar in water. Is considered to have been formed to solubilize the poorly water-soluble compound.

This (B) dye, in order to have sufficient water resistance,
It should be 0.5 to 30% by weight in the ink composition and 15% or more in the total weight of the dye in the ink. In ink composition
If it is 0.5% or less, the ability to solubilize the water resistance-imparting agent decreases, which becomes unstable over time and water resistance decreases.
Further, if it is 30% or more, precipitation of a dye occurs and it is unstable over time, which causes an increase in the viscosity of the ink, which is unsuitable as an ink for writing instruments, plotter pens, and ink jet printers. If it is less than 15% of the total dye weight of the ink, it will not be a good water resistant ink.

Then, among the poorly water-soluble compounds, a compound having a solubility of 5% by weight or more at 20 ° C. in ethyl alcohol is suitably solubilized.

The above-mentioned (B) dye used in the present invention has 0.1
Surface surface tension when dissolved by weight% is 60dy at 20 ℃
Examples of anionic dyes having n / cm or less are as follows.

Acid Dyes: CI Acid Yellow 40 CI Acid Orange 51 CI Acid Red 114,249 CI Acid Blue 83,90,103,127 CI Acid Green 25,27 Direct Dyes: CI Direct Black 154 Epoxy-added CI Direct Black 154 One or more of the above dyes Can be used.

The aromatic ring which is the above-mentioned component (C) used in the present invention, or a lipophilic group selected from aliphatic hydrocarbons having a C number of 6 to 12 and a group having at least one O, N or S atom. The poorly water-soluble compound containing one or more of both hydrophilic groups includes the following.

(A) a compound having a dicarboxylic acid ester skeleton (b) a compound having a benzophenone skeleton (c) a compound having a phenol skeleton (d) a compound having an imidazole skeleton (e) a compound having a benzothiazole skeleton (f) having a benzoin skeleton Compound (g) One or more compounds selected from compounds having a benzoic acid ester skeleton, and particularly a compound having a solubility of 5% by weight or more at 20 ° C. in ethyl alcohol.

Specific examples of (a) include diethyl sebacate, bis (2,
Examples include 2,6,6-tetramethyl-4-piperidyl) sebacate and bis (1,2,2,6,6-pentamethyl-4-piperidyl) sebacate.

Specific examples of (b) include benzophenone, 2,2-dihydroxy-4-methoxybenzophenone, and 2,4-dihydroxy-benzophenone.

Specific examples of (c) include ethyl 2,2-bis (4'-hydroxyphenyl) propane gallate, n-propyl gallate, isoamyl salicyl aldoxime gallate, 4-hydroxy-1,2, diethyl phthalate, para. tert-butylphenol and the like.

Specific examples of (d) include benzimidazole.

Specific examples of (e) include 2-chloro, benzothiazole, 2-methyl-5chlorobenzothiazole, and 2mercaptobenzothiazole.

Specific examples of (f) include benzoin methyl ether.

Specific examples of (g) include propyl para-hydroxybenzoate and phenylbenzoate.

One or more of the above compounds can be used.

The above-mentioned (D) dye used in the present invention contains 0.1% water.
Examples of anionic dyes whose surface tension when dissolved by weight% exceeds 60 dyn / cm at 20 ° C. are as follows.

Acid Dyes: CI Acid Yellow 6,23 CI Acid Red 1,37,73,87,92 CI Acid Blue 80 Direct Dyes: CI Direct Yellow 44 CI Direct Red 4,9,23,31,227 CI Direct Blue 1,15 , 86, 87, 199 CI Direct Black 19 One or more of the above dyes can be used.

The ink of the present invention uses water as a solvent component, but for the purpose of preventing the ink from drying, improving the solubility of the dye, increasing the solubilization amount of the poorly water-soluble compound, etc. When a substance such as the one exemplified above is blended, the performance such as dry-up resistance is improved.

Ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, glycerin, polyglycerin, polyethylene glycol, polypropylene glycol, methyl cellosolve, ethyl cellosolve, butyl cellosolve, methyl carbitol, ethyl carbitol, butyl carbitol, propylene glycol methyl Ether, dipropylene glycol methyl ether, tripropylene glycol methyl ether, 3 methyl 3-methoxybutanol,
2-pyrrolidone, triethanolamine, urea and its derivatives.

Examples of the urea derivative include thiourea, ethylene urea, hydroxyethyl urea, hydroxypropyl urea, ethylene thiourea and diethyl thiourea.

One or more of the above substances can be used.

In addition to the above components, the ink of the present invention may contain p-
Methyl oxybenzoate, 1,2-benzisothiazoline-
Antibacterial agent such as 3-on, rust preventive agent such as benzotriazole and butoxyethyl acid phosphate diethylamine salt, viscosity adjusting agent composed of polyvinylpyrrolidone, polyvinyl alcohol, cellulose derivative, water-soluble resin such as maleic acid resin, and interface A surface tension adjusting agent such as an activator or a sticking property improving agent such as a polymer emulsion for improving the sticking property to a non-permeable support such as a polyester film can be appropriately added within a range not impairing the performance of the ink. .

Next, the production method of the water-based ink of the present invention will be briefly described. After the anionic dye is completely dissolved in water, a poorly water-soluble compound may be added and dissolved.

In addition, it is preferable to dissolve by stirring at room temperature or higher. Particularly, 80 ° C or higher is suitable.

After confirming that the poorly water-soluble compound is completely solubilized, other components are added and dissolved by stirring to obtain an ink.

[Examples] Next, the present invention will be described with reference to Examples and Comparative Examples. Regarding the components (B), (C) and (D) described above, the symbols (B), (C) and (D) are attached in front of the components for easy understanding.

Example 1 (B) CI Acid Blue 90 (surface tension 52.3 dyn / cm) 0.
75 parts by weight (D) CI Direct Yellow 44 (surface tension 63.5 dyn / c
m) 4.25 parts by weight (C) 2,2-bis (4'-hydroxyphenyl) propane (solubility 5% by weight or more) 1.00 parts by weight Polyethylene glycol # 200 20.00 parts by weight Triethanolamine 1.00 parts by weight Proxel XL-2 1.00 parts by weight Parts (A) Ion-exchanged water 72.00 parts by weight 100.00 parts by weight Operation: Acid Blue 90 and Direct Yellow 44 are completely dissolved by stirring in ion-exchanged water (60 ° C) 2,
2-Bis (4'-hydroxyphenyl) propane is added and the mixture is heated with stirring at 80 ° C for 1 hour. Next, the remaining components were added, and the mixture was stirred at room temperature for 1 hour, and then allowed to cool and filtered, and the yellow of Direct Yellow 44 was added to the blue of Acid Blue 90 to obtain a toned yellow-green ink.

Example 2 (B) CI Acid Blue 90 (surface tension 52.3 dyn / cm) 0.
75 parts by weight (D) CI Acid Red 92 (surface tension 69.5 dyn / cm) 4.
25 parts by weight (C) 2,2-bis (4'-hydroxyphenyl) propane (solubility 5% by weight or more) 1.00 parts by weight Polyethylene glycol # 200 20.00 parts by weight Triethanolamine 1.00 parts by weight Proxel XL-2 1.00 parts by weight ( A) Ion-exchanged water 72.00 parts by weight 100.00 parts by weight Operation: After acid blue 90 and acid red 92 are completely dissolved by stirring in ion-exchanged water (60 ° C) 2,2-
Add bis (4'-hydroxyphenyl) propane to 80
Stir for 1 hour at ℃. Next, the remaining components were added, and the mixture was stirred at room temperature for 1 hour, left standing to cool, and then filtered to add a red color of Acid Red 92 to a blue color of Acid Blue to obtain a toned magenta ink.

Example 3 (B) CI Acid Yellow 40 (surface tension 37.4 dyn / cm)
5.0 parts by weight (D) CI Acid Red 73 (surface tension 64.8 dyn / cm) 2.
0 parts by weight (C) Benzoin methyl ether (solubility 5% by weight or more) 1.0 parts by weight Ethylene glycol 10.0 parts by weight Diethylene glycol 10.0 parts by weight Triethanolamine 2.0 parts by weight Proxel XL-2 1.0 parts by weight (A) Ion-exchanged water 69.00 parts by weight 100.00 parts by weight Operation: Acid Yellow 40 and Acid Red 73 are completely dissolved by stirring in ion-exchanged water (60 ° C), benzoin methyl ether is added, and the mixture is heated and stirred at 80 ° C for 1 hour. Next, the remaining components were added, and the mixture was stirred at room temperature for 1 hour, and then allowed to cool and filtered, and the red color of Acid Red 73 was added to the yellow color of Acid Yellow 40 to obtain a toned red-orange ink.

Example 4 (B) CI Acid Yellow 40 (surface tension 37.4 dyn / cm)
5.0 parts by weight (D) CI Direct Blue 87 (surface tension 68.4 dyn / cm)
1.0 parts by weight (C) bis (2,2,6, -tetramethyl-4-piperidyl)
Sebacate (solubility 5 wt% or more) 1.0 parts by weight Ethylene glycol 10.0 parts by weight Diethylene glycol 10.0 parts by weight Triethanolamine 2.0 parts by weight Proxel XL-2 1.0 parts by weight (A) Ion-exchanged water 70.00 parts by weight 100.00 parts by weight Operation: Acid Yellow 40 and Direct Blue 87 were completely dissolved by stirring in ion-exchanged water (60 ° C), and bis (2,2,6,6, -tetramethyl-4-piperidyl) sebacate was added. Heat and stir at 80 ° C for 1 hour. Next, the remaining components were added, and the mixture was stirred at room temperature for 1 hour, left standing to cool, and then filtered to obtain a yellow-green ink in which the yellow of Acid Yellow 40 and the blue of Direct Blue 87 were toned.

Example 5 (B) CI Acid Blue 90 (surface tension 52.3 dyn / cm) 4.
0 parts by weight (D) CI Direct Yellow 44 (surface tension 63.5 dyn / c
m) 2.0 parts by weight (C) 2,2-bis (4'-hydroxyphenyl) propane (solubility 5% by weight or more) 1.0 parts by weight ethylene glycol 10.0 parts by weight diethylene glycol 10.0 parts by weight triethanolamine 1.0 part by weight Proxel XL-2 1.0 parts by weight (A) Ion-exchanged water 71.00 parts by weight 100.00 parts by weight Operation: Acid Blue 90 and Direct Yellow 44 are completely dissolved by stirring in ion-exchanged water (60 ° C) 2,
2-Bis (4'-hydroxyphenyl) propane is added and the mixture is heated with stirring at 80 ° C for 1 hour. Next, the remaining components were added, and the mixture was stirred at room temperature for 1 hour, allowed to cool and filtered, and the blue of Acid Blue 90 was added with the yellow of Direct Yellow 44 to obtain a toned yellow-green ink.

Example 6 (B) CI Acid Blue 90 (surface tension 52.3 dyn / cm) 2.
5 parts by weight (D) CI Acid Red 92 (surface tension 69.5 dyn / cm) 2.
5 parts by weight (C) Benzyl paraoxybenzoate (solubility 5% by weight or more) 1.0 part by weight D Polyethylene glycol # 200 20.0 parts by weight Triethanolamine 1.0 parts by weight Proxel XL-2 1.0 parts by weight (A) Ion-exchanged water 72.00 parts by weight 100.00 parts by weight Operation: Acid Blue 90 and Acid Red 92 are completely dissolved in ion-exchanged water by stirring (60 ° C), benzene paraoxybenzoate is added, and the mixture is heated and stirred at 80 ° C for 1 hour. Next, the remaining components were added, and the mixture was stirred at room temperature for 1 hour, then left standing to cool and then filtered to obtain a toned magenta ink by adding the red color of Acid Red 92 to the blue color of Acid Blue 90.

Comparative Example 1 (B dye less than 15%) (B) CI Acid Blue 90 (surface tension 52.3 dyn / cm)
5 parts by weight (D) CI Direct Yellow 44 (surface tension 63.5 dyn / c
m) 4.5 parts by weight (C) 2,2-bis (4'-hydroxyphenyl) propane (solubility 5% by weight or more) 1.0 parts by weight Polyethylene glycol # 200 20.0 parts by weight Triethanolamine 1.0 parts by weight Proxel XL-2 1.0 parts by weight Parts (A) Ion-exchanged water 72.00 parts by weight 100.00 parts by weight Operation: Acid Blue 90 and Direct Yellow 44 are completely dissolved by stirring in on-exchange water (60 ℃) 2,2
-Bis (4'-hydroxyphenyl) propane was added, and the mixture was heated and stirred at 80 ° C for 1 hour. Next, the remaining components were added, and the mixture was stirred at room temperature for 1 hour, left standing to cool, and then filtered to obtain a green ink.

Comparative Example 2 (B dye less than 15%) (B) CI Acid Blue 90 (surface tension 52.3 dyn / cm)
5 parts by weight (D) CI Acid Red 92 (surface tension 69.5 dyn / cm) 4.
5 parts by weight (C) 2,2-bis (4'-hydroxyphenyl) propane (solubility 5% by weight or more) 1.0 parts by weight Polyethylene glycol # 200 20.0 parts by weight Triethanolamine 1.0 parts by weight Proxel XL-2 1.0 parts by weight ( A) Ion-exchanged water 72.00 parts by weight 100.00 parts by weight Operation: After acid blue 90 and acid red 92 are completely dissolved by stirring in ion exchange water (60 ° C) (C)
2,2-Bis (4'-hydroxyphenyl) propane was added and the mixture was heated with stirring at 80 ° C for 1 hour. Next, the remaining components were added, and the mixture was stirred at room temperature for 1 hour, left standing to cool, and then filtered to obtain a reddish purple ink.

 The compositions of Examples and Comparative Examples are shown in Table 1.

Comparative Test The ink compositions obtained in Examples and Comparative Examples were tested for stability over time and water resistance on paper by the following test methods. The results are shown in Table 2.

(Test method) Water resistance on paper Immediately after writing, the handwriting is immersed in water for 1 minute, and the presence or absence of ink bleeding and stains on the writing paper is observed.

 ◎ No ink bleeding, no writing paper stains.

 ○ There is a slight bleeding out of the ink and no stain on the writing paper.

 △ Many ink bleeds and stains on writing paper.

 × Almost no writing lines remain.

Stability with time The physical properties after being left in a glass container at 50 ° C. for 60 days were measured, and the physical properties were compared with those before aging.

In addition, the presence or absence of precipitation of dyes, water resistance-imparting agents, etc. was observed with an optical microscope (magnification: 100 times).

(Microscope) ◎ Almost no change in physical properties before and after aging.

 No precipitation.

 ○ Slight changes in physical properties before and after aging.

 No precipitation.

 × Large changes in physical properties before and after aging.

 Or there is precipitation.

Viscosity: Viscosity measured at 20 ° C with a B-type viscometer manufactured by Tokyo Keiki Co., Ltd.

 pH: Toa Denpa Kogyo Co., Ltd. pH meter was used.

Surface tension: Surface tension meter CBUPA manufactured by Kyowa Interface Science Co., Ltd.
Measure the value at 20 ℃ with -3 type.

(Effect) The ink of the present invention is extremely excellent in water resistance on paper and stability over time, as is clear from the comparative test, and is suitable as an ink for writing instruments, plotter pens, and ink jet printers. It is something.

Claims (3)

[Claims] 1. An amount of 0.5 to 30% by weight in (A) water and (B) ink composition, and 15% by weight or more in the total weight of dyes in the ink, and 0.1% by weight in water
An anionic dye having a surface tension of 60 dyn / cm or less at 20 ° C. when dissolved and (C) an aromatic ring or an aliphatic hydrocarbon having a C number of 6 to 12 as a lipophilic group, and O, N and S atoms A poorly water-soluble compound containing at least one group as a hydrophilic group and one or more of each of these groups, and having a solubility of 5% by weight or more at 20 ° C. when the compound is dissolved in ethyl alcohol. (D) as a color tone adjusting agent in an ink composition prepared by blending with a water resistance-imparting agent whose effective component is (D) anionic type having a surface tension of more than 60 dyn / cm at 20 ° C. when dissolved in water at 0.1% by weight A water resistant ink composition containing a dye. 2. The water-resistant ink composition according to claim 1, wherein the water resistance-imparting agent as the component (C) is 0.5 to 5% by weight in the ink composition. 3. An anionic dye of (B) and an anionic dye of (D) are added to water of (A) to completely dissolve them, and then a water resistance-imparting agent of (C) is added thereto to obtain room temperature or higher. A method for producing a water-resistant ink composition, which comprises stirring at the temperature of 1, and then adding and mixing the remaining components.