JP3013476B2 - Ink composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink composition having excellent drying resistance used for writing instruments, recorders, ink jet printing and the like, and more particularly to an ink which is used in a ballpoint pen and has good ink discharge.

[0002]

2. Description of the Related Art Conventionally, inks used for writing instruments, recorders, ink jet printing, and the like mainly contain a coloring material, a water-soluble organic solvent, and water. When the ink is used, phenomena such as thickening of the ink and deposition of a coloring material occur due to evaporation of the water in the ink. As a result, a decrease in the ink discharge from the pen tip (so-called blurring) and an ink Problems such as a decrease in ink ejection from the ejection holes (so-called clogging) occur. Therefore, in order to prevent the occurrence of the above-mentioned problems, conventionally, as a water-soluble organic solvent, a glycol-based solvent such as ethylene glycol, diethylene glycol, triethylene glycol, or thiodiglycol, or a highly water-soluble organic solvent such as glycerin has been used. Boiling materials were used.

That is, in order to obtain good drying resistance, the above-mentioned conventional ink has been designed to make up for the water evaporated by the hygroscopicity of the water-soluble organic solvent.

[0004]

However, the water-soluble organic solvent is generally a compound having a high viscosity.
On the other hand, ink used for writing instruments, recorders, ink jet printing, and the like is ejected through a capillary such as a pen tip or an orifice, and therefore, its viscosity needs to be 20 cps or less (25 ° C.). .

[0005] Therefore, the amount of the water-soluble organic solvent that can be used is limited with respect to the conventional ink, and the amount used within the limit is completely insufficient to compensate for evaporated water.

That is, in the above-mentioned conventional inks, inks having good ink ejection properties have poor drying resistance, and inks having good drying resistance have poor ink ejection properties.
It has been very difficult to obtain an ink having both good ink ejection properties and good drying resistance.

The first object of the present invention is to provide an ink composition having both good ink dischargeability and drying resistance, and further improved ink dischargeability of the ink composition. The second object is to provide

[0008]

SUMMARY OF THE INVENTION The present invention provides a colorant,
(Poly) oxyethylene- (poly) oxypropylene-
(Poly) oxyalkylene glycol and hexamethyl
At least consisting of tetracosane or hexamethyltetracosahexaene and having a viscosity of 20 cps or less (25 ° C.)
The gist of the present invention is an ink composition .

Hereinafter, the present invention will be described in detail. As the coloring material, conventionally known dyes and pigments can be used alone or in combination. Dyes include acid dyes such as CI Acid Red 52, CI Acid Blue 1, CI Acid Black 2, and 123, CI Direct Black 19, CI Direct Blue 86, and the like. Basic dyes such as CI Basic Blue 7 and CI Basic Red 1;
CI Solvent Black 7, 123, CI Solvent Red 8, 49, 100, CI Solvent Blue 2, 25, 55, 70, CI Solvent Green 3, C.I. CI Solvent Yellow 21, 61, C.I.
Oil-soluble dyes such as CI Solvent Orange 37, CI Solvent Violet 8 and CI Solvent Violet 21;
It is preferable to use a dye soluble in an alcohol solvent or a nigrosine dye.

Pigments include azo pigments, condensed polyazo pigments, phthalocyanine pigments, quinacridone pigments, indigo pigments, thioindigo application nitroso pigments, nitro pigments, basic dye pigments, acidic dye pigments, Vat dye pigments, organic pigments such as mordant dye pigments and natural dye pigments and iron black, carbon black, ocher, barium yellow,
Inorganic pigments such as navy blue, cadmium red, titanium oxide, red iron oxide and the like.

(Poly) oxyethylene- (poly) oxypropylene- (poly) oxyalkylene glycol is
It is used as a solvent and is represented by the following formula 1.

Embedded image _{HO- (C 2 H 4 O)} a- (C 3 H 6 O) b- (R-O) c-H ( where, a, b, c = 1~80 , R = CnH2n, n = 1 ~ 10)

In the present invention, those in which a = b = c = 1 are expressed as oxyethylene-oxypropylene-oxyalkylene glycol, and the others are expressed as polyoxyethylene-polyoxypropylene-polyoxyalkylene glycol. .

As specific examples, Unisafe MT (average molecular weight 170), Unilube 50 MB-2 (average molecular weight 2)
00), 50 MB-5 (average molecular weight 500)
Nippon Yushi Co., Ltd.), Unipol 50HB-55 (average molecular weight 240), 50HB-100 (average molecular weight 54)
0) (above, manufactured by Sanyo Chemical Industry Co., Ltd.), the amount of which is 70 to 99% by weight based on the total amount of the ink composition.
Is preferred.

Hexamethyltetracosane or hexamethyl
Letetracosahexaene improves ink ejection
Used for various purposes, such as animal livers and human skin
Fats, especially those that are abundant in shark liver oil. Specific examples and
Squalane as hexamethyltetracosane
(Nikko Chemicals Co., Ltd.), hexamethyltetracosa
Hexaene is squalene EX (Nikko Chemicals
(Made in Japan). The amount used is based on the total amount of the ink composition.
It is preferably 0.1 to 20% by weight.

In addition, other than the above essential components, if necessary, water,
Alcohols, ketones, glycol ethers, S
Aromatics such as ters, chlorinated solvents, benzene, and toluene
Solvent, ethylene glycol, propylene glycol,
Glycol solvents such as diethylene glycol, glycer
A known solvent such as phosphorus, an antiseptic / antifungal agent, a rust inhibitor
Can be selected and used.

In order to obtain the ink composition of the present invention, a conventionally known method can be used. As an example, when a dye is used as a coloring material, each component is obtained by stirring and mixing using a stirrer, and when a pigment is used, each component is dispersed and mixed using a disperser. Obtained by

[0017]

The polyoxy used in the ink composition of the present invention.
Ethylene-polyoxypropylene-polyoxyalkylene
Glycol has low viscosity and is almost
As it does not evaporate, an ink with excellent drying resistance can be obtained.
You. By further containing unsaturated hydrocarbon oil
Improved wettability, especially for ballpoint pen-type writing instruments
Ink with excellent ink ejection from the pen tip
Can be

[0018]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples.
In the Examples and Comparative Examples, “parts” simply means “parts by weight”.
Show.

Embodiment 1 C.I. I. Solvent Black 7 10.0 parts Unilube MB50-2 80.0 parts Squalane 5.0 parts Sorbitan 5.0 parts The above components were stirred and mixed using a stirrer to give a black ink composition.
A product was obtained.

Embodiment 2 C.I. I. Acid Red 52 (Water-soluble dye) 5.0 parts Unipol 50HB-100 80.0 parts Squalene EX 15.0 parts The above components were prepared in the same manner as in Example 1 to obtain a red ink composition.
I got something.

Embodiment 3 C.I. I. Solvent Blue 2 8.0 parts Unilube MB50-2 90.0 parts Squalene EX 1.0 part Diethylene glycol 1.0 part The above components were prepared in the same manner as in Example 1, and a blue ink composition was prepared.
I got something.

Example 4 Monarch 1000 10.0 parts Unipol 50HB-100 80.0 parts Squalane 8.0 parts Ammonium salt of styrene-acrylic acid (dispersant) 2.0 parts The above components were mixed using a sand mill type disperser. Disperse and mix black
A color ink composition was obtained.

Comparative Example 1 CI Direct Blue 86 (aqueous dye) 20.0 parts Glycerin 30.0 parts Water 50.0 parts The above components were prepared in the same manner as in Example 1 to obtain a black ink composition.
I got something.

Comparative Example 2 CI Direct Black 19 (aqueous dye) 15.0 parts Glycerin 10.0 parts Water 75.0 parts The above components were prepared in the same manner as in Example 1 to obtain a red ink composition.
I got something.

[0025]

The effects obtained in Examples 1 to 4 and Comparative Examples 1 and 2 are as follows.
Drying test, quick writing test, aging
A viscosity change test and a writing test were performed. Table 1 shows the results.
And Table 2.

Drying resistance test: Method;
Ballpoint pens made with water-based dye inks sold (Super Ball
BH14, manufactured by Pentel Co., Ltd.)
g, filling and writing at a temperature of 20 ° C and a humidity of 65%.
After leaving for a certain period with the cap removed from the tool,
I wrote by hand on the quality paper and observed the handwriting. Evaluation: ○: writable, Δ: slightly blurred, ×: not writable
Noh

Quick writing test: Method : A writing instrument prepared in the same manner as in the above-mentioned drying resistance test was used.
Using a moving writing tester, writing speed 14 cm / sec, writing load 1
Quality paper (JIS P3
Continuous writing on 201 writing paper A)
Nothing was observed. Evaluation: ○: writable, Δ: slightly blurred, ×: not writable
Noh

Time-dependent viscosity change test: A 60 cm diameter petri dish of 60 ml of each ink composition
And open at 25 ° C and 50% humidity
And leave it for 30 days to measure the viscosity of the ink composition before and after the test
did. Measurement conditions: 25 ° C., using a B-type viscometer.

Writing test: Method: Each ink composition was prepared using a commercially available water-based dye ink.
Lupen (Lowry Refill CFL6, Pentel Co., Ltd.)
1.0g was filled in the same writing instrument as
The distance until the writing faded was measured. Ink ejection amount: A commercially available rotating continuous writing force measuring machine (spiral
Machine), writing speed 7 cm / sec, load 100 g,
A continuous writing test was conducted under the condition of an angle of 70 °.
The ink consumption at 0 m writing was measured. (unit:
g) Blurring distance: In the above continuous writing test, blurring in handwriting
The distance to the occurrence of was measured.
The limit sample and handwriting were visually compared and judged.)
(Unit: m)

[0030]

[Table 1]

[0031]

[Table 2]

As described in detail above, the present invention
The ink composition has excellent drying resistance of the ink. Therefore,
Water evaporates and viscosity increases like conventional water-based inks
Excellent features that eliminate the drawback that makes writing impossible by
Have Furthermore, the ink ejection amount is excellent, especially
When used for ballpoint pens, brushes until blurring occurs
The recording distance has also been significantly improved, making the ink composition excellent in practical use.
You. In addition, this ink composition is used for rubber stamps and stamps.
Useful as ink that requires drying resistance, such as g
It is something.

[0033]

[0034]

[0035]

[0036]

[0037]

[0038]

[0039]

[0040]

[0041]

[0042]

[0043]

──────────────────────────────────────────────────の Continued on the front page (31) Priority claim number Japanese Patent Application No. 3-47260 (32) Priority date January 28, 1991 (1991.1.128) (33) Priority claim country Japan (JP) (56) References JP-A 1-230685 (JP, A) JP-A 62-89776 (JP, A) JP-A 57-201700 (JP, A) JP-A 55-1552769 (JP, A) 55-31866 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C09D 11/00-11/20

Claims (1)

(57) [Claims] 1. A colorant, comprising (poly) oxyethylene-
(Poly) oxypropylene- (poly) oxyalkylene glycol and hexamethyltetracosane or hexame
An ink composition comprising at least tyltetracosahexaene and having a viscosity of 20 cps or less (25 ° C.).