JPH0940901A - Writing composition for paper for writing with water-containing brush - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a writing compsn. which is used for writing on paper for writing with a water-contg. brush, is prepd. simply, has no fear for staining, is safe, and can maintain written lines for a relatively long time by incorporating a hydrophilic org. solvent having a specified vapor pressure or lower into water. SOLUTION: This compsn., for writing on paper which is used for writing with a water-contg. brush and has a surface layer comprising a material having clarity increased by permeation of a writing fluid to enable the color of the underlayer to be clearly visible, is formed from water and a hydrophilic org. solvent having a vapor pressure at 20 deg.C of 1.0mmHg or lower and contains 0.001-0.5wt.% xanthane gum and/or carboxyvinyl polymer. Suitable examples of the solvent are 1,3-butylene glycol and glycerol because of their low toxicity and skin-irritating properties. Known kinds of such paper can be used. This compsn. may be applied to such paper by writing with a calligraphy writing brush having a pointed head and impregnated with the compsn. or by storing the compsn. in a pen body and supplying it through a pen tip having capillary action.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a writing composition for writing paper. More specifically, transparency is improved by penetration of a writing composition mainly composed of water, and a handwriting with a color tone of the lower layer appears, and the handwriting disappears by evaporation of the writing composition. The present invention relates to a writing composition for writing paper that can be applied to writing paper that can reveal an image.

[0001]

2. Description of the Related Art Conventionally, the surface layer of a part written with water becomes transparent or semi-transparent to reveal the handwriting by revealing the color tone of the base, and when the water evaporates or penetrates and the surface layer dries, the handwriting becomes clear. A brush paper that disappears and can be used repeatedly has been disclosed (Japanese Patent Publication No. 50-5097).
Issue). As the writing liquid used for the above-mentioned writing paper, water is generally used in consideration of its simplicity and safety so that it is not dangerous for children to use.

The writing liquid used for the above-mentioned conventional writing paper actually depends on the evaporation of water, even if it is suitable to use water in order to satisfy the convenience and safety. It is difficult to keep the handwriting legible for a long time by using it for lessons in schools, schools, etc., and the time for keeping the handwriting depends on the room temperature or humidity, but it is limited to about several minutes. Therefore, it is inconvenient to use the calligraphy to hold the stroke order and handwriting. Therefore, the present invention intends to provide a writing composition for writing paper, which maintains the handwriting readable for a relatively long time in the writing liquid used for the conventional writing paper, and solves the above-mentioned problems. .

[0003]

The writing composition for writing paper of the present invention is a writing composition for writing on a writing paper having a surface layer of a material exhibiting a color tone of the lower layer, the transparency of which is improved by permeation of a writing liquid. The above composition requires a writing composition for water writing paper, which comprises water and a hydrophilic organic solvent having a vapor pressure at 20 ° C. of 1.0 mmHg or less. Further, the writing composition for writing paper requires a writing composition for writing paper containing xanthan gum and / or carboxyvinyl polymer in an amount of 0.001 to 0.5% by weight. Furthermore, the hydrophilic organic solvent requires a writing composition for water writing paper selected from isoprene glycol, 1,3 butanediol, and glycerin.

As the solvent used for the writing composition, a hydrophilic organic solvent having a vapor pressure at 20 ° C. of 1.0 mmHg or less is preferably used. Since the organic solvent is easily dissolved in water and has a vapor pressure of 1.0 mmHg or less, evaporation of the writing composition can be appropriately suppressed depending on the purpose, as compared with the case where only water is used. Examples of the hydrophilic organic solvent having a vapor pressure of 1.0 mmHg or less used in the writing composition include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, polyethylene glycol, 1,3 butanediol,
Isoprene glycol, hexylene glycol, 1,3
Butylene glycol, glycerin, polyhydric alcohols such as ethyl carbitol, or 1 of glycol ethers
One kind or two or more kinds can be used, and 1,3 butylene glycol, isoprene glycol and glycerin, which have low toxicity and irritation to the skin, are preferably used. Further, as the hydrophilic organic solvent, a solvent suitable for the handwriting holding time is selected, and an appropriate amount is added.

Further, in order to prevent bleeding of handwriting and sagging of the writing liquid when the writing composition is impregnated in a writing brush while keeping the writing surface in a vertical state, an appropriate resin may be blended. Although possible, xanthan gum or carboxyvinyl polymer is effective and 0.001 in the writing composition
It is added in the range of 0.5 wt% to prevent bleeding and sagging of handwriting and suppress the permeation of the writing liquid into the surface layer. If it is added in an amount of 0.5% by weight or more, the viscosity increases to cause writing failure, or it adheres to the writing paper to form a film after evaporation of water and the hydrophilic organic solvent, which makes repeated use difficult. . Further, if the addition amount is 0.001% by weight or less, desired writing performance cannot be imparted.

As the above-mentioned writing paper, conventionally known writing paper is used. The brush paper, for example, after forming a colored layer such as black or red appearing as handwriting on the paper surface,
The writing paper described in Japanese Patent Publication No. 50-5097 in which a water-permeable white layer containing a low-refractive material such as amorphous silica or aluminum oxide is formed on the layer is preferably used.

As a method of applying the above-mentioned writing composition to a writing paper, a calligraphy brush having a brush tip at the tip may be impregnated for writing, or the writing composition may be built into the barrel to form a capillary tube. It may be applied or written with a writing tool configured to supply the writing composition to the writing nib having an action or other writing tip. Furthermore, an applicator such as a brush may be used, or it may be incorporated in a spray device and sprayed.

[0008]

When the writing composition obtained as described above is applied to a writing paper to form an arbitrary image, the writing composition permeates into the white layer of the surface layer to be transparent, and the underlying coloring layer is formed. The colored image can be seen by seeing through. The colored image is kept readable during the intended retention time depending on the selection and blending amount of the hydrophilic organic solvent, and then gradually becomes transparent by evaporation of the writing composition or penetration into the lower layer. It returns to the original white layer and the handwriting becomes invisible. Further, even when the writing composition is impregnated into a writing brush or the like while holding the writing paper vertically and writing is performed, since appropriate viscosity is imparted, dripping does not occur. Furthermore, the writing composition has high safety and is less irritating to the skin.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION In the examples and comparative examples of the present invention, all parts are parts by weight. Example 1 40 parts of isoprene glycol and 0.02 part of xanthan gum were added to 59.98 parts of water to obtain a writing composition. still,
The viscosity of the writing composition is 18.5 mPa · s at 20 ° C.
(20 rpm), 63 Pa · s (1 rpm), and the surface tension was 35.3 mN / m.

Example 2 54.95 parts of water, 45 parts of 1,3 butanediol, carboxyvinyl polymer [trade name: Hibiswako 104,
Wako Pure Chemical Industries, Ltd.] was added and mixed, then triethanolamine (neutralizing agent) was added and stirred with a disper to obtain a writing composition. The viscosity of the writing composition is 2
15.1 mPa · s (20 rpm), 27 mP at 0 ° C
The surface tension was a.s (1 rpm) and the surface tension was 38.5 mN / m.

Comparative Example 1 Water (100%) was used as a writing liquid.

Comparative Example 2 40 parts of isoprene glycol was added to 60 parts of water to obtain a writing composition. The viscosity of the writing composition was 6.9 mPa · s (20 rpm), 6 mPa · s (1
rpm) and the surface tension was 35.0 mN / m.

Brush paper of a calligraphy brush having a brush tip at its tip was impregnated with the writing compositions of Examples 1 and 2 and Comparative Examples 1 and 2, and the brush paper was held vertically (manufactured by Mishima Paper Co., Ltd.). ], And the presence or absence of liquid dripping was measured (20 ° C., 60% RH). Table 1 shows the time until the handwriting disappears and the presence or absence of liquid dripping.

[Table 1]

[0014]

EFFECTS OF THE INVENTION Since the writing composition for water writing paper of the present invention contains water as a main component and an appropriate amount of a hydrophilic organic solvent, it is relatively easy to prepare and there is no fear of contamination. Further, it is safe for children to use, and it is possible to maintain the handwriting for a relatively long time according to the purpose, and it is possible to provide a writing composition for writing paper suitable for lessons such as calligraphy. .

Claims (3)

[Claims] 1. The transparency is improved by penetrating the writing liquid,
A writing composition for writing on a writing paper provided with a surface layer of a material exhibiting a color tone of a lower layer, the composition comprising water and a hydrophilic organic solvent having a vapor pressure of 1.0 mmHg or less. Writing composition for use. 2. The writing composition for water-based writing paper comprises xanthan gum and / or 0.001 carboxyvinyl polymer.
The writing composition for writing paper according to claim 1, wherein the writing composition is contained in an amount of 0.5 to 0.5% by weight. 3. The writing composition for writing paper according to claim 1, wherein the hydrophilic organic solvent is selected from isoprene glycol, 1,3 butanediol, and glycerin.