JP2001226620A - Water-based ink composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an ink composition in which the problem of lowering of stirring property due to formation of precipitation layer by pigment in ink is solved from the aspect of compounding of ink component, enabling writing with pensile, etc., onto ink-coated surface. SOLUTION: This water-based ink composition comprises a pigment as a coloring material, a solvent and a resin. In the ink composition, 5.0-40.0 wt.% (based on total amount of ink) fiber selected from among natural fibers and chemical fibers and having 0.1 nm to 1 mm length is added to the ink.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink composition, and more particularly, to a writing instrument, a stamp, a recorder,
The present invention relates to an aqueous ink composition that can be used for printers, printing, and the like.

[0002]

2. Description of the Related Art Conventionally, in an ink having a high concealing property on a coating surface of a correction liquid or the like, a large amount of pigment particles such as titanium oxide are dispersed in the ink, and the concealing property of the coating surface is increased by a thick layer of the pigment particles. keeping. When such an ink is stored for a long time, the pigment particles settle, and therefore, the stirring of the ink is indispensable for use. Even in actual products, steel balls, stirring rods, etc. are used as the ink stirring means. Stirrer is provided. However, as a result of containing a large amount of pigment such as titanium oxide in the ink, pigment particles are deposited during storage to form a hard cake, and it may be difficult to stir by a stirrer.

On the other hand, a method of adding asbestos to ink has been known as a technique devising the ink component itself in order to prevent the formation of a firm precipitate layer due to the pigment component (Japanese Patent Publication No. 52-40256, etc.). . However, asbestos is a substance that has a harmful effect on the human body, as is well known, and its use in writing instruments and the like must be carefully performed.

[0004]

As described above, in order to solve the problem of the deterioration of the stirring property due to the formation of the precipitation layer due to the pigment in the ink from the aspect of mixing the ink components, a new ink component which is harmless to the human body. You need to use a substance.
In addition, since the surface coated with the ink is a smooth surface having a high gloss, when drawing is performed on the coated surface with a writing instrument, ink is poorly applied, and drawing with graphite such as a pencil is almost impossible. There was a problem that it was impossible. Therefore, there has been a need for a technique that enables writing on an ink-coated surface even when a writing instrument such as a pencil that performs writing with fine irregularities on the surface of the writing surface is used.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies in view of the above-mentioned circumstances, and as a result, by adding predetermined natural fibers or chemical fibers to an aqueous ink in which titanium oxide or the like is dispersed. The present inventors have found that an ink composition that can easily stir the ink, is highly safe for the human body, and can be written on a coated surface with a pencil or the like can be obtained, and has completed the present invention.

That is, the present invention provides a pigment as a coloring material,
In an aqueous ink composition containing a solvent and a resin,
0.1 nm length selected from natural fiber or chemical fiber
The present invention relates to an aqueous ink composition containing 5.0 to 40.0% by weight of a fiber of 〜1 mm based on the total amount of the ink.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The natural fibers used in the present invention are:
For example, it is a fiber obtained using wood, grass, silk thread, cotton, etc. as raw materials, and specific examples include paper clay (solid content), silk thread (cut and crushed), absorbent cotton (crushed), and the like. can do. It is preferable to cut or crush these fibers by using, for example, a refiner used in a beating process in producing paper or the like. The chemical fiber used in the present invention is a fiber obtained by an artificial polymerization reaction, and specific examples thereof include nylon fiber, acrylic fiber, polyester fiber and the like. The above natural fibers or chemical fibers can be used alone or in combination of two or more.

[0008] The length of the natural fiber or chemical fiber blended in the ink composition of the present invention varies depending on the type of a product using the ink, but is preferably about 0.1 nm to 1 mm. In particular, when a pen type is used and the pen tip is used as an ink for a fiber bundle core or a thin pipe-shaped product used for a normal marker, the length of the fiber to be added is set to 0. .1 nm to 200 n
m, more preferably 0.1 nm to 100 μm
It is desirable that In addition, especially when used as ink for products that are pen-type and valve-type nibs whose nibs are used for direct liquid type markers, or bottle-types where the ink is applied directly with a brush When used as an ink for the above-mentioned product, the length of the fiber to be added is more preferably about 0.1 nm to 1 mm, and more preferably 10 nm to 5 μm.

The thickness of the natural fiber or the chemical fiber may be, for example, 0.1 nm to 10 nm in cross section from the viewpoint of allowing the ink to pass through the flow path without interruption.
It is preferably about μm, more preferably about 0.1 nm to 1 μm.

The amount of the natural fiber or the chemical fiber in the ink composition of the present invention is about 5.0 to 40.0% by weight (hereinafter simply referred to as "%") based on the total amount of the ink composition. Preferably, 10.0 to 30.0% is more preferable.

The pigments, solvents and resins as coloring materials, which are other essential components in the ink composition of the present invention, include:
Any general ink can be used without particular limitation.

As pigments as coloring materials, titanium oxide,
Examples thereof include resin pigments, hollow resin pigments, resin emulsions, and the like. Examples of the solvent include water, alcohols such as ethanol and methanol, and mixtures of the alcohols and water, such as a mixture of 2-propanol and water at a ratio of 5:95, for example. Can be suitably used.

Examples of the resin include acrylic resin, styrene acrylic resin, vinyl resin and the like.

When the ink composition of the present invention is used as a correction liquid, a white marker, or the like, almost no coloring agent may be used. Is preferably added.
As the colorant, any of dyes and pigments (other than those described above) conventionally used in aqueous inks can be used without limitation. Here, preferred dyes include, for example, Aizen Burimura Red 4BH and Aizen Burimura Yellow G
Direct dyes such as CLH (above, manufactured by Eizen), Aizen Bonsaw RH, Eizen Opal Pink BH, Eizen Opal Black WH Extra Conc (below, Eizen), Orient Solble Blue OBX, Orient Solble Blue OBB (More , Manufactured by Orient Chemical Co., Ltd.)
And food dyes such as tartrazine, acid red, and phloxine (all manufactured by Eisen Co., Ltd.). Preferred pigments include, for example, carbon black, inorganic pigments such as iron oxide, phthalocyanine pigments, inorganic pigments and organic pigments such as azo pigments, inorganic fluorescent pigments such as calcium sulfide, and other organic fluorescent pigments. Can be The coloring agent can be used alone or in combination of two or more kinds.
It is preferable to add about 0%.

Further, in the ink composition of the present invention,
Since a pigment such as titanium oxide is used, it is desirable to use a dispersant. As a dispersant, for example, John Krill J
-62, John Krill J-450 (all manufactured by Johnson Company), Jolimer AT-210, Jolimer SEK-1
Any of those generally used in ink compositions, such as water-soluble resins such as 01 (all manufactured by Nippon Pure Chemical Industries, Ltd.), anionic surfactants, and nonionic surfactants can be used without limitation.

In the ink composition of the present invention, in addition to the above components, for example, sodium benzoate (manufactured by Wako Pure Chemical Industries, Ltd.), Bioden-18, Amorden-HS, Amorden BT-50, Amorden FS-14D ( Above, manufactured by Daiwa Chemical Industry Co., Ltd.), Proxel BDN, Proxel GXL,
A small amount of a bacteriostatic agent such as Proxel TN (all manufactured by Zeneca) can be added. In addition, as a pH adjuster, for example, aminomethylpropanol, triethanolamine (all manufactured by Wako Pure Chemical Industries, Ltd.) and the like can be added. In addition, a corrosion inhibitor for the tip of the ballpoint pen,
Lubricants can be used without limitation.

The aqueous ink composition of the present invention can be produced by the following method. In the case of a pigment ink or an ink using a pigment and a dye in combination, the above essential components and optional components are stirred and mixed or mixed using a known dispersing machine (for example, a ball mill, a roll mill, a sand mill, a flow mill, a dyno mill, an attritor, etc.). Smash. Next, the intermediate obtained by stirring and mixing or mixing and pulverization is treated by a method such as filtration and centrifugal sedimentation as necessary to remove coarse particles and dust, thereby easily forming the aqueous ink composition of the present invention. Things are obtained.

The aqueous ink composition of the present invention can be suitably used as an ink for writing instruments, stamps, recorders, printers, printing, painting, and the like. It has optimal properties as an ink for writing implements.

[0019]

The reason why good stirring properties are maintained in the aqueous ink composition of the present invention despite the fact that the pigment is blended has not been elucidated yet. When the pigment is settled and deposited, the fibers enter between the deposited layers and hinder the formation of a dense deposited layer by the pigment. As a result, the ink is easily re-stirred by a stirrer such as a glass ball. It is presumed that it becomes. In addition, by blending the fibers in the ink, fine irregularities similar to the paper surface are formed on the coating surface of the ink, which makes it possible to write with a pencil or the like on the coating film. It is considered that writing with a ballpoint pen, a marker, or the like is facilitated.

[0020]

Next, the present invention will be described in more detail with reference to examples and test examples, but the present invention is not limited to these examples. Example 1 White ink: (Composition) Compounding amount (parts by weight) Water 41.70 Titanium oxide (manufactured by DuPont) 38.00 Joncryl 62 (manufactured by Johnson) 10.00 Aminomethylpropanol 0.10 Bioden-18 (Manufactured by Daiwa Chemical Industry Co., Ltd.) 0.20 Paper clay (solid content) 10.00 (Production method) After mixing and grinding the above components, a white ink was obtained by filtering.

Example 2 Blue Ink: (Composition) Compounding Amount (parts by weight) Water 36.71 Titanium Oxide (Dupont) 35.00 Blue Colored Pigment (Dainichi Seika) 6.80 Joncryl 62 ( Johnson) 11.13 Triethanolamine 0.13 Proxel BDN (Zeneca) 0.23 Cut and crushed silk thread 10.00 (Production method) After mixing and crushing the above components, blue ink is obtained by filtration. I got

Example 3 Red ink: (Composition) Compounding amount (parts by weight) Water 30.87 Titanium oxide (manufactured by DuPont) 35.00 Eisen Blimura Red 4BH (manufactured by Eisen) 1.80 Jolimar AT210 (Japan) 12.00 Propylene glycol 10.00 Aminomethylpropanol 0.13 Amorden-HS (manufactured by Daiwa Chemical Industry Co., Ltd.) 0.20 Ground cotton 10.00 (Production method) The above components were mixed and ground. Thereafter, the mixture was filtered to obtain a red ink.

Example 4 Red ink: (Composition) Compounding amount (parts by weight) Water 19.77 Titanium oxide (manufactured by DuPont) 35.00 Eisen Burimura Red 4BH (Eisen Co.) 3.77 Eisen Burimura Yellow GCLH (manufactured by Eizen) 0.23 propylene glycol 30.00 triethanolamine 0.01 sodium benzoate 1.22 paper clay (solid content) 10.00 (production method) After mixing and stirring the above components, filtration is performed. As a result, a red ink was obtained.

Comparative Examples 1 to 4 Ink compositions were obtained in the same manner as in Examples 1 to 4 except that water was added instead of the paper clay, silk thread and absorbent cotton in the above Examples.

Test Examples The inks obtained in Examples 1 to 4 and Comparative Examples 1 to 4 were filled in a modified pen container (Mitsubishi CLP301; manufactured by Mitsubishi Pencil Co.),
The ink spread on the paper. After drying the ink, writing and drawing were performed on the coated film using a pencil or the like. As a result, in any of the comparative examples, it was somewhat difficult to write on the glossy coating surface like the conventional correction liquid, whereas in any of the examples, the coating was easy to write with a pencil or the like. Surface was obtained.

Using the ink filled in the correction pen container, vibration for re-stirring is applied by hand one month after the manufacture, and the number of vibrations until the glass ball built in the ink storage chamber starts to move. It was measured. Table 1 shows the results.
Shown in

[0027]

[Table 1]

As is evident from Table 1, the glass ball started to move with the same number of vibrations as the conventional correction liquid in each of the comparative examples, while the ball moved with a smaller number of times in each of the examples. Has begun.

[0029]

The water-based ink composition of the present invention has excellent performance for re-stirring the pigment and has a good coated surface on which overpainting is possible. In addition, the fibers blended in the aqueous ink composition of the present invention have high safety to the human body and are therefore suitable for use in writing instruments and the like which are used daily.

Claims (2)

[Claims] 1. An aqueous ink composition containing a pigment, a solvent and a resin as a coloring material, wherein a fiber having a length of 0.1 nm to 1 mm selected from natural fibers or chemical fibers is added to 5.0 parts of the total amount of the ink. Aqueous ink composition containing 〜40.0% by weight. 2. The aqueous ink composition according to claim 1, wherein the solvent is an alcohol or a mixed solvent of alcohol and water.