JPH055072A - Ink composition - Google Patents

Abstract

(57) [Summary] [Structure] An ink composition comprising at least a coloring material such as a dye or a pigment and a polyoxyethylene-polyoxypropylene-polyoxyethylene glycol solvent. [Effect] Since the nib has excellent drying resistance and further has excellent ink dischargeability, it can be used for writing instruments, recorders, ink jet printing, etc., and is particularly good for ballpoint pens.

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, which is used for writing instruments, recorders, ink jet printing, and the like, and more particularly, to an ink which is excellent in ink ejection when used in a ballpoint pen.

[0002]

2. Description of the Related Art Conventionally, inks used for writing instruments, recorders, ink jet printing, etc. are mainly composed of a coloring material, a water-soluble organic solvent and water. When the above ink is used, phenomena such as thickening of ink and precipitation of coloring material occur due to evaporation of water in the ink, and as a result, decrease in ink ejection from the pen tip (so-called scraping) and ink Problems such as a decrease in ink discharge from the discharge holes (so-called clogging) occur. Therefore, in order to prevent the occurrence of the above problems, conventionally, as a water-soluble organic solvent, a glycol solvent such as ethylene glycol, diethylene glycol, triethylene glycol, thiodiglycol, or a high hygroscopic property such as glycerin. It used a boiling material.

That is, the above-mentioned conventional ink has a design concept of compensating for evaporated water due to the hygroscopicity of the water-soluble organic solvent in order to obtain good drying resistance.

[0004]

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

Therefore, there is a limit to the amount of the water-soluble organic solvent that can be used in the conventional ink, and the amount within the limit is not sufficient to compensate the evaporated water.

That is, in the above conventional ink, the ink exhibiting good ink discharge property is inferior in drying resistance, and the ink having good dry resistance is inferior in ink discharging property.
It has been very difficult to obtain an ink having both good ink dischargeability and drying resistance.

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

[0008]

The present invention is directed to a coloring material,
(Poly) oxyethylene- (poly) oxypropylene-
An ink composition comprising at least a (poly) oxyalkylene glycol and having a viscosity of 20 cps or less (25 ° C.) is defined as a first gist, and a coloring material and a (poly) oxyethylene- (poly) oxypropylene- (poly) An ink composition comprising at least oxyalkylene glycol and colloidal sol and having a viscosity of 20 cps or less (25 ° C.) is defined as a second gist, and a coloring material and (poly) oxyethylene- (poly) oxypropylene- (poly A third aspect is an ink composition comprising at least oxyalkylene glycol and a hydrocarbon oil and having a viscosity of 20 cps or less (25 ° C.).

The present invention will be described in detail below. 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, etc. Direct dyes, basic dyes such as CI Basic Blue 7 and CI Basic Red 1, C.I.
CI Solvent Black 7, 123, CI Solvent Red 8, 49, 100, CI Solvent Blue 2, 25, 55, 70, CI Solvent Green 3, C.I. I. Solvent Yellow 21, 61, C.I.
Oil-soluble dyes such as C. I. Solvent Orange 37, C.I. Solvent Violet 8 and 21.
It is preferable to use a dye soluble in an alcohol solvent or a nigrosine dye.

The pigments include azo pigments, condensed polyazo pigments, phthalocyanine pigments, quinacridone pigments, indigo pigments, thioindigo pigments nitroso pigments, nitro pigments, basic dye pigments, acid dye pigments, Organic pigments such as vat dye pigments, mordant dye pigments and natural dye pigments, iron black, carbon black, ocher, barium yellow,
Inorganic pigments such as navy blue, cadmium red, titanium oxide and red iron oxide can be mentioned.

(Poly) oxyethylene- (poly) oxypropylene- (poly) oxyalkylene glycol is
It is used as a solvent and is represented by the following chemical 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 to 10)

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

As specific examples, Unisafe MT (average molecular weight 170), Unilube 50MB-2 (average molecular weight 2)
00), 50MB-5 (average molecular weight 500) (above,
Nippon Oil & Fats Co., Ltd., Unipol 50HB-55 (average molecular weight 240), the same 50HB-100 (average molecular weight 54)
No. 0) (above, Sanyo Chemical Industry Co., Ltd.), and the amount used is 70 to 99% by weight with respect to the total amount of the ink composition.
Is preferred.

The colloidal sol is used for improving the dischargeability of an ink composition comprising a coloring material and (poly) oxyethylene- (poly) oxypropylene- (poly) oxyalkylene glycol, and water is used. It is a colloidal solution in which ultrafine particles of titania, silica, alumina, zirconia, etc. are dispersed in water as a dispersion medium. Commercially available products are NS-200 and NS- as titania sol.
210 (above, manufactured by Ishihara Sangyo Co., Ltd.), as silica sol Snowtex-S, O, C, 20L, 30
(Above, manufactured by Nissan Chemical Industries, Ltd.), Cataloid (Cat
alloid) S-20L, same S-20H, same S30L,
SI-30, SI40, SI-50, SI-3
50, SI500, SI-45P, SI-80
P, the same SN (these are manufactured by Catalysts & Chemicals Industry Co., Ltd.), alumina sol as alumina sol-100, 200, 300
(These are manufactured by Nissan Chemical Industries, Ltd.). The amount used is preferably 0.1 to 20% by weight with respect to the total amount of the ink composition.

The hydrocarbon oil is used for the same purpose as the above colloidal sol, and is an unsaturated hydrocarbon contained in the liver oils of various animals and human sebum, especially in shark liver oil. Specific examples thereof include hexamethyltetracosane (squalane; manufactured by Nikko Chemicals Co., Ltd.), hexamethyltetracosahexaene (squalene EX; manufactured by Nikko Chemicals Co., Ltd.), and the like. The amount used is preferably 0.1 to 20% by weight with respect to the total amount of the ink composition.

In addition to the above essential components, water may be added if necessary.
Alcohols, ketones, glycol ethers, esters, chlorinated solvents, benzene, aromatic solvents such as toluene, ethylene glycol, propylene glycol,
A glycol solvent such as diethylene glycol, a known solvent such as glycerin, an antiseptic / antifungal agent, a rust inhibitor, etc. can be appropriately selected and used.

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, it is obtained by stirring and mixing each component with a stirrer, and when a pigment is used, each component is dispersed and mixed with a disperser. Obtained by

[0018]

The polyoxyethylene-polyoxypropylene-polyoxyalkylene glycol used in the ink composition of the present invention has a low viscosity and hardly evaporates over time, so that an ink excellent in drying resistance can be obtained. can get. Furthermore, by containing a colloidal sol or a hydrocarbon oil, the wettability is improved, and particularly when used in a ballpoint pen-type writing instrument, an ink having an excellent ink discharge amount from the pen tip can be obtained.

[0019]

EXAMPLES The present invention will be described in more detail below with reference to examples.
In the examples and the comparative examples, simply "part" means "part by weight".

Example 1 CI Solvent Blue 2 (alcohol-soluble dye) 10 parts Unilube MB50-2 90 parts The above components were stirred and mixed using a stirrer to obtain a blue ink composition.

Example 2 CI Acid Black 123 (alcohol-soluble dye) 10 parts Unilube MB50-2 85 parts Dipropylene glycol 5 parts The same components as in Example 1 were used to obtain a black ink composition. It was

Example 3 CI Solvent Black 7 (alcohol-soluble dye) 10 parts Unipol 50HB-100 85 parts Diethylene glycol 5 parts The same components as in Example 1 were used to obtain a black ink composition. ..

Example 4 CI Solvent Red 100 (alcohol-soluble dye) 10 parts Unipol 50HB-55 85 parts benzene 5 parts The same components as in Example 1 were used to obtain a red ink composition. ..

Example 5 CI Solvent Blue 2 10 parts Unisafe MT (manufactured by NOF CORPORATION) 90 parts The same components were used as in Example 1 to obtain a blue ink composition.

Example 6 CI Solvent Black 7 10 parts Unisafe MT (manufactured by NOF CORPORATION) 85 parts Diethylene glycol 5 parts The same components as in Example 1 were used to obtain a black ink composition. ..

Example 7 C. I. Acid Black 123 10 parts Unilube MB50-2 80 parts Alumina sol 100 5 parts Sorbitan 5 parts The above components were treated in the same manner as in Example 1 to obtain a black ink composition.

Example 8 C. I. Solvent Black 7 5 parts Unipol 50HB-100 80 parts Snowtex S 15 parts The same components were used as in Example 1 to obtain a black ink composition.

Example 9 C. I. Solvent Yellow 34 (alcohol-soluble dye) 8 parts Unilube MB50-2 90 parts Snowtex 20L 1 part Diethylene glycol 1 part The above components were processed in the same manner as in Example 1 to obtain a yellow ink composition.

Example 10 Monarch 1000 (Carbon Black, manufactured by Cabot Corporation, USA) 10 parts Unipol 50HB-100 80 parts Snowtex 30 8 parts Ammonium salt of styrene-acrylic acid 2 parts The mixture was dispersed and mixed to obtain a black ink composition.

Example 11 C. 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 treated in the same manner as in Example 1 to obtain a black ink composition.

Example 12 C. 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 treated in the same manner as in Example 1 to obtain a red ink composition.

Example 13 C. I. Solvent Blue 2 8.0 parts Unilube MB50-2 90.0 parts Squalene EX 1.0 parts Diethylene glycol 1.0 parts The above components were processed in the same manner as in Example 1 to obtain a blue ink composition.

Example 14 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 used in a sand mill type disperser. Were dispersed and mixed to obtain a black ink composition.

Comparative Example 1 CI Direct Blue 86 (Aqueous Dye) 20.0 parts Glycerin 30.0 parts Water 50.0 parts The same components as in Example 1 were used to obtain a black ink composition. It was

Comparative Example 2 CI Direct Black 19 (Aqueous Dye) 15.0 parts Glycerin 10.0 parts Water 75.0 parts The same components as in Example 1 were used to obtain a red ink composition. It was

[0036]

The ink compositions obtained in Examples 1 to 14 and Comparative Examples 1 and 2 were subjected to a drying resistance test, a quick writing test, a viscosity change test with time, and a writing test. The results are shown in Table 1.
And shown in Table 2.

Drying Resistance Test: Method: Each ink composition was prepared using a commercially available water-based dye ink ballpoint pen (Super Ball BH14, Pentel Co., Ltd.).
2.0g filled with a writing instrument similar to that of the above), left at a temperature of 20 ° C. and a humidity of 65% for a certain period of time with the cap removed from the writing instrument, and then handwritten on a fine-quality paper. I observed. Evaluation: ○: Writing is possible, △: There is some blurring, ×: Writing is not possible

Rapid writing test: Method: Using a writing instrument prepared in the same manner as in the above-mentioned drying resistance test, using an automatic writing tester, a writing speed of 14 cm / sec, a writing load of 1
Fine paper (JIS P3
201 Writing paper A) was continuously written, and the presence or absence of blurring was observed. Evaluation: ○: Writing is possible, △: There is some blurring, ×: Writing is not possible

Viscosity change test with time: 60 m of each ink composition
1 in a Petri dish with a diameter of 10 cm, and the temperature is 25 ° C.
The ink composition was allowed to stand for 30 days in an open state under the condition of a humidity of 50%, and the viscosity of the ink composition before and after the test was measured. Measurement condition: 25
℃, B type viscometer used.

Written test: Method: Each ink composition is a commercially available ball-point pen using an aqueous dye ink (Lowry Refill CFL6, Pentel Co., Ltd.).
1.0 g was filled in a writing instrument similar to
The distance until the occurrence of writing scratches was measured. Ink discharge rate: Using a commercially available rotation type continuous writing power 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 °, and the first 10
Ink consumption was measured at 0 m writing. (unit:
g) Blurred distance: In the above continuous writing test, the distance until the blur was generated in the handwriting was measured (the occurrence of the blur was judged by visually comparing the limit sample of the handwriting with the handwriting).
(Unit: m)

[0041]

[Table 1]

[0042]

[Table 2]

As described in detail above, the ink composition of the present invention is excellent in ink drying resistance. Therefore,
It has an excellent feature that it eliminates the disadvantage that writing becomes impossible due to evaporation of water and increase in viscosity, like conventional water-based inks. Furthermore, it is excellent in ink discharge amount,
When used for a ballpoint pen, the writing distance until the occurrence of blurring is significantly improved, and the ink composition is excellent in practical use. The ink composition of the present invention is also useful as an ink that requires drying resistance, such as rubber stamps and stamp inks.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (31) Priority claim number Japanese Patent Application No. 3-47260 (32) Priority date Hei 3 (1991) January 28 (33) Priority claim country Japan (JP)

Claims (1)

Claims: 1. A coloring material and (poly) oxyethylene-
An ink composition comprising at least (poly) oxypropylene- (poly) oxyalkylene glycol and having a viscosity of 20 cps or less (25 ° C.). 2. A coloring material and (poly) oxyethylene-
At least (poly) oxypropylene- (poly) oxyalkylene glycol and colloidal sol,
An ink composition having a viscosity of 20 cps or less (25 ° C.). 3. A coloring material and (poly) oxyethylene-
An ink composition comprising at least (poly) oxypropylene- (poly) oxyalkylene glycol and a hydrocarbon oil and having a viscosity of 20 cps or less (25 ° C.).