JPH09272835A - Aqueous ink for writing tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an aqueous ink for writing tool, capable of improving wetting properties of a water-repellent resin without lowering surface tension and suppressing bleeding of a holograph. SOLUTION: In this aqueous ink for a writing tool obtained by dissolving or dispersing a colorant into an aqueous medium containing a humectant, 0.4-10.0wt.% calculated as a nonvolatile content of an emulsion of a three- dimensional copolymer composed of methyl methacrylate, butyl acrylate and methacrylic acid is dissolved or dispersed into the aqueous solvent.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water-based ink applied to writing instruments such as ballpoint pens, felt-tip pens, marking pens and fountain pens.

[0002]

2. Description of the Related Art Conventionally, low-viscosity water-based ink has been used for ballpoint pens, felt-tip pens, marking pens, fountain pens and the like.

[0003]

However, in general, a water-based pen using a water-based ink has a tendency that the ink flow is affected by a change in room temperature, a change in atmospheric pressure, or the like, and the ink may seep out from the pen tip. , There is a problem of flowing out. Increasing the surface tension of the ink to prevent this has the problem that the ink will not flow easily.
In an ink storage cylinder made of a water-repellent resin (polypropylene resin, polyethylene resin, etc.) having an inner diameter of 8 mm or less, there is a problem that the surface tension of the water-based ink causes the water-based ink to be held by itself and difficult to flow.

Further, the water-based ink has a problem that when writing on a paper surface, the ink penetrates between the fibers of the paper and the handwriting is blurred. Therefore, according to the present invention, in order to facilitate the flow of ink without lowering the surface tension, the wettability with respect to the ink storage cylinder, the ink guide core, the pen core, etc. can be improved, and the bleeding of handwriting can be suppressed. It provides a water-based ink.

[0005]

A water-based ink for a writing instrument, wherein a coloring material is dissolved or dispersed in an aqueous solvent containing a humectant, which comprises three types of methyl methacrylate, butyl acrylate and methacrylic acid in the aqueous solvent. It has been found that by dissolving or dispersing the terpolymer emulsion consisting of the monomer species of (1), the water-repellent resin is improved in wettability, and at the same time, a water-based ink having no bleeding of handwriting is obtained.
The present invention has been completed.

A terpolymer emulsion consisting of three monomer species of methyl methacrylate, butyl acrylate and methacrylic acid is used in an amount of 0.4% by weight or more in terms of nonvolatile content to remarkably improve wettability. Can
In particular, when 2.2% to 2.3% by weight is mixed and dispersed, it is most suitable for suppressing bleeding and wettability. On the other hand, 10.0% by weight
When it exceeds, the continuous writing distance becomes shorter because the viscosity increases.

The above terpolymer emulsion is 0.4 to
The change in surface tension caused by mixing 10.0% by weight is
It is 1 dyne / cm or less, and the change in viscosity is 1.0 cp or less. As the coloring material, dyes and pigments are used, and it is preferable to use them in the range of 6 to 10% by weight in the ink composition.

In addition to the above components, if necessary, a penetrant is 0 to 0.1% by weight, a surfactant is 0 to 0.1% by weight, a rust preventive, a preservative, and a fungicide are 0 to. It is preferably used in the range of 1% by weight. Penetrant, so as not to reduce the surface tension too much
It is desirable to add a small amount of the surfactant.

[0009]

【Example】

 Example 1

[Table 1] parts by weight Water Black 100L (dye) 50.0 parts (water content 84% by weight) ethylene glycol (moisturizer) 30.0 parts score roll 900 (penetrant) 0.1 parts (Kao Soap Co., Ltd. ), Polyoxyethylene nonyl henol ether) PRYSURF M208B (surfactant) 0.1 part (Daiichi Kogyo Seiyaku Co., Ltd., phosphoric acid ester) benzotriazole (rust inhibitor) 0.5 part Biocide 880 (anti-protection agent) Mold, antiseptic) 0.2 part (Taisho Technos Co., Ltd.) Triethanolamine (PH adjusting agent) 1.0 part Three-dimensional composition consisting of three monomer species of methyl methacrylate, butyl acrylate and methacrylic acid Copolymer emulsion (content 44.5 to 47.5% by weight in terms of non-volatile content, volatile content (water) content 55.5 to 52.5% by weight) 1.0 part Water 17.1 parts

The above ethylene glycol and score roll 9
00, Prysurf M208B, benzotriazole,
Mix biocide 880 and triethanolamine,
The mixture was heated to 50 to 60 ° C., stirred with a stirrer for 20 minutes and mixed. Next, while stirring, WaterBlack 100L, water, above 3
Add the original copolymer emulsion in that order, stir for about 30 minutes,
A black aqueous ink was obtained by filtration.

Embodiment 2

[Table 2] Parts by weight Water Black 100L (dye) 50.0 parts (water content 84% by weight) Ethylene glycol (moisturizer) 30.0 parts Score Roll 900 (penetrant) 0.1 parts (Kao Soap (stock) ), Polyoxyethylene nonyl henol ether) PRYSURF M208B (surfactant) 0.1 part (Daiichi Kogyo Seiyaku Co., Ltd., phosphoric acid ester) benzotriazole (rust inhibitor) 0.5 part Biocide 880 (anti-protection agent) Mold, antiseptic) 0.2 part (Taisho Technos Co., Ltd.) Triethanolamine (PH adjusting agent) 1.0 part Three-dimensional composition consisting of three monomer species of methyl methacrylate, butyl acrylate and methacrylic acid Copolymer emulsion (content 44.5 to 47.5% by weight in terms of non-volatile content, volatile content (water) content 55.5 to 52.5% by weight) 5.0 parts water 13.1 parts

The above ethylene glycol and score roll 9
00, Prysurf M208B, benzotriazole,
Mix biocide 880 and triethanolamine,
The mixture was heated to 50 to 60 ° C., stirred with a stirrer for 20 minutes and mixed. Next, while stirring, WaterBlack 100L, water, above 3
Add the original copolymer emulsion in that order, stir for about 30 minutes,
A black aqueous ink was obtained by filtration.

Embodiment 3

[Table 3] Parts by weight Water Black 100L (dye) 50.0 parts (water content 84% by weight) Ethylene glycol (moisturizer) 30.0 parts Score Roll 900 (penetrant) 0.1 parts (Kao Soap (stock) ), Polyoxyethylene nonyl henol ether) PRYSURF M208B (surfactant) 0.1 part (Daiichi Kogyo Seiyaku Co., Ltd., phosphoric acid ester) benzotriazole (rust inhibitor) 0.5 part Biocide 880 (anti-protection agent) Mold, antiseptic) 0.2 part (Taisho Technos Co., Ltd.) Triethanolamine (PH adjusting agent) 1.0 part Three-dimensional composition consisting of three monomer species of methyl methacrylate, butyl acrylate and methacrylic acid Copolymer emulsion (content 44.5 to 47.5% by weight in terms of non-volatile content, volatile matter (water) content 55.5 to 52.5% by weight) 10.0 parts water 8.1 parts

The above ethylene glycol and score roll 9
00, Prysurf M208B, benzotriazole,
Mix biocide 880 and triethanolamine,
The mixture was heated to 50 to 60 ° C., stirred with a stirrer for 20 minutes and mixed. Next, while stirring, WaterBlack 100L, water, above 3
Add the original copolymer emulsion in that order, stir for about 30 minutes,
A black aqueous ink was obtained by filtration.

Example 4

[Table 4] Parts by weight Water Black 100L (dye) 50.0 parts (water content 84% by weight) Ethylene glycol (moisturizer) 30.0 parts Score Roll 900 (penetrant) 0.1 parts (Kao Soap (stock) ), Polyoxyethylene nonyl henol ether) Benzotriazole (rust inhibitor) 0.5 part Biocide 880 (mold inhibitor, preservative) 0.2 part (Taisho Technos Co., Ltd.) Triethanolamine (PH adjuster) 1.0 part Methyl methacrylate, butyl acrylate and methacrylic acid terpolymer emulsion consisting of three types of monomers (content of non-volatile components 44.5 to 47.5% by weight, volatile components ( Water) Content 55.5-52.5% by weight) 5.0 parts Water 13.2 parts

The above ethylene glycol and score roll 9
00, benzotriazole, biocide 880, and triethanolamine were mixed, heated to 50 to 60 ° C., and stirred and mixed with a stirrer for 20 minutes. Then, while stirring, Wate
r Black 100L, water and the above terpolymer emulsion were added in this order, stirred for about 30 minutes and then filtered to obtain an aqueous black ink.

Embodiment 5

[Table 5] Parts by weight Carbon black (pigment) 8.0 parts Johncryl 62 (dispersant) 7.4 parts (Johnson Co., acrylic / styrene dispersant aqueous solution) Ethylene glycol (moisturizer) 10.0 parts Glycerin (humectant) 20.0 parts Nonsal OK-1 (lubricant) 1.0 part (NOF Corporation, potassium oleate) benzotriazole (rust inhibitor) 0.5 part Biocide 880 (mold inhibitor, Preservative) 0.2 parts (Taisho Technos Co., Ltd.) Triethanolamine (PH adjusting agent) 2.0 parts Ternary copolymer consisting of three monomer species of methyl methacrylate, butyl acrylate and methacrylic acid Emulsion (content 44.5 to 47.5% by weight in terms of nonvolatile content, volatile matter (water) content 55.5 to 52.5% by weight) 1.0 part Water 49.9 parts

Carbon black, John Cryl 62, ethylene glycol and glycerin were premixed for 2 hours using a stirrer. Next, after milling for 16 hours using a sand mill, coarse particles were removed with a centrifuge to remove non-sal OK-1, benzotriazole, and biocide 88.
0, triethanolamine, the above terpolymer emulsion and water while stirring, and the mixture was stirred for 2 hours and then filtered to obtain a water-based black ink.

Example 6

[Table 6] Parts by weight Carbon black (pigment) 8.0 parts Johncryl 62 (dispersant) 7.4 parts (Johnson Corp., acrylic / styrene-based dispersant aqueous solution) Ethylene glycol (moisturizer) 10.0 parts Glycerin (humectant) 20.0 parts Nonsal OK-1 (lubricant) 1.0 part (NOF Corporation, potassium oleate) benzotriazole (rust inhibitor) 0.5 part Biocide 880 (mold inhibitor, Preservative) 0.2 parts (Taisho Technos Co., Ltd.) Triethanolamine (PH adjusting agent) 2.0 parts Ternary copolymer consisting of three monomer species of methyl methacrylate, butyl acrylate and methacrylic acid Emulsion (content 44.5 to 47.5% by weight in terms of nonvolatile content, volatile content (water) content 55.5 to 52.5% by weight) 5.0 parts Water 45.9 parts

Carbon black, John Cryl 62, ethylene glycol and glycerin were premixed for 2 hours using a stirrer. Next, after milling for 16 hours using a sand mill, coarse particles were removed with a centrifuge to remove non-sal OK-1, benzotriazole, and biocide 88.
0, triethanolamine, the above terpolymer emulsion and water while stirring, and the mixture was stirred for 2 hours and then filtered to obtain a water-based black ink.

Example 7

[Table 7] Parts by weight Carbon black (pigment) 8.0 parts Johncryl 62 (dispersant) 7.4 parts (Johnson Corp., acrylic / styrene-based dispersant aqueous solution) Ethylene glycol (moisturizer) 10.0 parts Glycerin (humectant) 20.0 parts Nonsal OK-1 (lubricant) 1.0 part (NOF Corporation, potassium oleate) benzotriazole (rust inhibitor) 0.5 part Biocide 880 (mold inhibitor, Preservative) 0.2 parts (Taisho Technos Co., Ltd.) Triethanolamine (PH adjusting agent) 2.0 parts Ternary copolymer consisting of three monomer species of methyl methacrylate, butyl acrylate and methacrylic acid Emulsion (content 44.5 to 47.5% by weight in terms of nonvolatile content, volatile matter (water) content 55.5 to 52.5% by weight) 10.0 parts water 40.9 parts

Carbon black, John Cryl 62, ethylene glycol and glycerin were premixed for 2 hours using a stirrer. Next, after milling for 16 hours using a sand mill, coarse particles were removed with a centrifuge to remove non-sal OK-1, benzotriazole, and biocide 88.
0, triethanolamine, the above terpolymer emulsion and water while stirring, and the mixture was stirred for 2 hours and then filtered to obtain a water-based black ink.

Comparative Example 1

[Table 8] parts by weight Water Black 100L (dye) 50.0 parts (water content 84% by weight) ethylene glycol (humectant) 30.0 parts score roll 900 (penetrant) 0.1 parts (Kao Soap (stock) ), Polyoxyethylene nonyl henol ether) PRYSURF M208B (surfactant) 0.1 part (Daiichi Kogyo Seiyaku Co., Ltd., phosphoric acid ester) benzotriazole (rust inhibitor) 0.5 part Biocide 880 (anti-protection agent) Mold, antiseptic) 0.2 part (Taisho Technos Co., Ltd.) Triethanolamine (PH adjuster) 1.0 part Water 18.1 part

The above ethylene glycol and score roll 9
00, Prysurf M208B, benzotriazole,
Mix biocide 880 and triethanolamine,
The mixture was heated to 50 to 60 ° C., stirred with a stirrer for 20 minutes and mixed. Next, with stirring, WaterBlack 100L and water were added in that order, and after stirring for about 30 minutes, filtration was performed to obtain a water-based black ink.

Comparative Example 2

[Table 9] Parts by weight Carbon black (pigment) 8.0 parts Johncryl 62 (dispersant) 7.4 parts (Johnson Corp., acrylic / styrene dispersant aqueous solution) Ethylene glycol (moisturizer) 10.0 parts Glycerin (humectant) 20.0 parts Nonsal OK-1 (lubricant) 1.0 part (NOF Corporation, potassium oleate) benzotriazole (rust inhibitor) 0.5 part Biocide 880 (mold inhibitor, Preservative) 0.2 parts (Taisho Technos Co., Ltd.) Triethanolamine (PH adjusting agent) 2.0 parts Water 50.9 parts

Carbon black, John Cryl 62, ethylene glycol and glycerin were premixed for 2 hours using a stirrer. Next, after milling for 16 hours using a sand mill, coarse particles were removed with a centrifuge to remove non-sal OK-1, benzotriazole, and biocide 88.
The mixture was added to 0, triethanolamine and water with stirring, stirred for 2 hours and then filtered to obtain an aqueous black ink.

The water-based inks of Examples 1 to 7 and Comparative Examples 1 and 2 were placed in a polypropylene resin ink container, and in order to check the effect of wettability, the water-based ink was collected from below. After gently inverting it and holding it vertically, the subsequent process was observed. In the case of the water-based inks of Examples 1 to 7, the water-based inks were transferred to the ink storage cylinders at the same time when they were reversed, and quickly moved from the upper side to the lower side. Therefore, even after 1 hour or more, the water-based ink did not fall while being accumulated above. By applying vibration to the left and right, I was able to finally fall down.

Using a ball-point pen equipped with an ink container containing the water-based inks of Examples 1, 2 and Comparative Example 1 among the sample inks, at a speed of 20 cm / s,
After writing with the pen tip perpendicular to the paper surface, the thickness of the handwriting after 10 minutes was measured. Assuming that the thickness of the water-based ink of Example 2 was "1", the thickness of Example 1 was "1.
4 ”, and the thickness of the water-based ink of Comparative Example 1 was“ 1.8 ”. Further, in the handwriting written in Comparative Example 1, a phenomenon in which a large number of fine lines branched in the vertical direction from the written line was observed with the naked eye, but in the handwriting written in Example 1 and Example 2,
Such fine branch lines were hardly observed with the naked eye.

[0029]

As described above, in the water-based ink for a writing instrument of the present invention, due to the action of the terpolymer emulsion consisting of three monomer species of methyl methacrylate, butyl acrylate and methacrylic acid in the composition. The wettability of the water-repellent resin can be improved. So, for example,
In a direct liquid type water-based ballpoint pen, the flow of ink to the ink storage cylinder, the ink guide core, and the pen tip can be made smooth, or the ink flow between the ink storage cylinder and the pen core, and between the pen core and the ink guide core can be made smooth. Since it can be done, it is possible to eliminate the tip pool where the ink pools at the tip of the chip. At the same time, it is possible to obtain a water-based ink in which handwriting is not blurred.

Claims (1)

[Claims] 1. An aqueous ink for a writing instrument, wherein a coloring material is dissolved or dispersed in an aqueous solvent containing a humectant, wherein the aqueous solvent contains three monomer species of methyl methacrylate, butyl acrylate and methacrylic acid. A water-based ink for a writing instrument, wherein the terpolymer emulsion is dissolved or dispersed in an amount of 0.4 to 10.0% by weight in terms of nonvolatile content.