JPH07126567A - Water-base marking pen ink for overhead projector - Google Patents

Abstract

PURPOSE:To provide a water-base marking pen ink which can dry without blushing within a short time on the surface of a sheet for an overhead projector by dissolving a water-soluble dye in a water-base vehicle containing a specified polyvinyl acetal resin. CONSTITUTION:A PVA of a degree of polymerization of 100-600 and a degree of saponification of 75mol% or above is acetalized with a 1-4C aldehyde to obtain a polyvinyl acetal resin of a degree of acetalization of 1-30mol%. 2-15wt.% water-soluble dye is dissolved in a water-base vehicle containing 0.1-5wt.% this resin, 50-80wt.% water, 20wt.% or below assistant for improving the drying rate of ink and the dissolution of dye and resin, 15wt.% or below glycol ether and 10wt.% or below glycerol, ethylene glycol or the like.

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 for a marking pen for writing on a transparent plastic sheet for an overhead projector (hereinafter abbreviated as OHP).

[0002]

2. Description of the Related Art Handwriting on the surface of a sheet with this type of water-based ink causes a whitening phenomenon due to the condensation of moisture in the atmosphere due to the heat of vaporization that is lost when the solvent evaporates, and the image projected by OHP is blackened. It tends to be bad.
In order to suppress this whitening phenomenon, it is customary to add a high boiling water-soluble organic solvent to the ink, but addition of a sufficient amount prevents the handwriting from drying, and if something touches the handwriting, the handwriting will spread and become unreadable. The situation that happens will occur. JP-A-5
No. 8-132061 discloses an invention of a water-based marking pen ink for OHP in which polyvinyl alcohol which is a water-soluble resin is added to suppress the whitening phenomenon. However, the ink rapidly increases in viscosity due to evaporation of water, and tends to inhibit the outflow of ink from the pen tip of the marking pen. In Japanese Patent Publication No. 54-37539, an OHP comprising a dye, a transparent fixing agent, water and a water-soluble organic solvent.
Although a water-based ink for use is disclosed, since an alkali-soluble resin such as shellac or maleic acid resin is used as the fixing agent, when applied to a marking pen, the pen tip is generated by evaporation of the ink solvent at the pen tip. The ink outflow from the ink tends to be defective, and it is not suitable as a marking pen.

[0003]

SUMMARY OF THE INVENTION According to the present invention, even when continuously writing, ink is smoothly discharged from the tip of a marking pen, and the surface of an OHP sheet is dried in a short time.
It is intended to provide a water-based marking pen ink for OHP which produces a handwriting which does not exhibit a whitening phenomenon.

[0004]

The aqueous marking pen ink for OHP of the present invention has a composition in which a water-soluble dye is dissolved in an aqueous vehicle containing a specific polyvinyl acetal resin. The polyvinyl acetal resin has a polymerization degree of 100.
To 600, an acetalization product of polyvinyl alcohol (hereinafter abbreviated as PVA) having a saponification degree of 75 mol% or more with an aldehyde having 1 to 4 carbon atoms (acetalization degree of 1 to 30 mol%), and 0.1 to 5 in the ink composition. It is used in a range of 0.2% by weight, preferably 0.2 to 2.5% by weight.

Water-soluble dyes used are tartrazine (CI. Acid Yellow 23) and Acid Yellow P.
Y (CI. Acid Yellow 131), Sunset Yellow (CI. Hood Yellow 3), Orange 1 (CI.
Acid Orange 20), Acid Orange 2B (C
I. Solvent Red 22), New Coccin (CI.
Acid Red 18), Acid Red FB (CI. Acid Red 52), Eosin GH (CI. Acid Red 87), Phloxine (CI. Acid Red 9)
2), Acid Violet 6B (CI. Acid Violet 49), Blue 7000 (CI. Acid Blue 1), Brilliant Blue FCF (CI. Acid Blue 9), Water Blue 105 (CI. Acid Blue 90), Brilliant Blue P- Acid dye such as 1 (CI. Acid Blue 104), Water Black 1
Direct dyes such as 30-L (CI. Direct Black 154), Water Blue 3 (CI. Direct Blue 87), methyl violet (CI. Basic Violet 1), Crystal Violet (CI. Basic Violet 3), Rhodamine B ( CI. Basic Violet 10), Victoria Pure Blue (C
I. Basic Blue 7), Malachite Green (C
I. It is a basic dye such as Basic Green 4) and is used in the range of 2 to 15% by weight in the ink composition.

The solvent is mainly water, and it is used in the ink composition.
Used in the range of up to 80% by weight. Ethanol, propanol, isopropanol and butanol are used in the ink composition in the range of up to 20% by weight as a dye and resin dissolution aid for controlling the ink drying rate, and glycol ethers such as propylene glycol monomethyl ether and ethylene glycol monomethyl ether are used in the ink composition. In the range of up to 15% by weight, glycerin, ethylene glycol, propylene glycol, diethylene glycol, low molecular weight polyethylene glycol, 2-pyrrolidone, 1,3-butylene glycol and the like are used in the range of up to 10% by weight in the ink composition.

In addition, an anionic or nonionic surfactant is added to the ink composition in an amount of 0.1 to 3% by weight in order to impart wettability to the plastic sheet surface of the ink.

[0008]

The polyvinyl acetal resin exerts an effect of suppressing the whitening phenomenon of the handwriting in the ink like the water-soluble resins such as PVA, shellac and maleic acid resin, but is compared with the ink containing the other water-soluble resin. Thus, even if the solvent is evaporated to some extent, the viscosity does not rise sharply and the insolubilization does not occur. Therefore, the water-based marking pen ink of the present invention,
Even if the marking pen is continuously written, good ink outflow from the pen tip is maintained.

[0009]

EXAMPLES Table 1 shows the compositions of the example inks and the comparative example inks. The numerical values of the compositions in the table are expressed in parts by weight, and the ink composition of Comparative Example 2 is the same as that of Japanese Patent Publication No. 54-3.
The composition of Example 1 ink described in JP-A-7539, and the ink composition of Comparative Example 3 is the composition of Example 2 ink described in JP-A-58-132061.

[0010]

[Table 1]

Details of the ink raw materials used will be described below according to the note numbers in the table. 1. CI. Solvent Red 22 2. CI. Acid Yellow 131 3. CI. Acid Blue 104 4. CI. Acid Blue 9 5. CI. Acid Violet 49 6. 6. A 25% aqueous solution of an acetalized product of PVA (polymerization degree: 500, saponification degree: 88 mol%, butyralization degree: 10 mol%). 7. A 25% aqueous solution of an acetalized product of PVA having a degree of polymerization of 300 and a degree of saponification of 98 mol% (degree of acetoacetalization of 6 mol% and degree of butyralization of 5 mol%). The following components were mixed and prepared by stirring while heating to 35 to 45 ° C. Dry bleached shellac 40 parts by weight 28% aqueous ammonia 5 morpholine 2 ethanol 14 water 39 9. 10. Polyvinyl alcohol having a degree of polymerization of about 500 and a degree of saponification of 86.5 to 89 mol% 10. Sodium salt of dialkyl sulphosuccinate 11. Polyoxyethylene oleyl ether sulfate (addition of 3 mol oxyethylene, sodium salt)

The sample ink was prepared by mixing the components shown in Table 1,
Prepared by stirring. A sample pen A is prepared by filling a predetermined amount of sample ink into a marking pen equipped with a 3.6 mmφ fiber pen molded by resin-processing a polyester fiber bundle and an ink absorber made of a polyester fiber bundle.
A marking pen provided with a 1 mmφ plastic pen molded from a polyacetal resin and the ink storage material was filled with a predetermined amount of sample ink and used as a sample pen B in the following test. Observation of occurrence of whitening phenomenon of handwriting Under predetermined conditions of 20 to 25 ° C and 70% RH, write a predetermined character on the polyester film with sample pen A, and write immediately after that and after leaving for 3 days under the same conditions. The degree of blackening of the characters projected over OHP was observed. Ink outflow from pen tip when continuously written The prescribed sentence was continuously written on a polyester film with sample pen B, and the ink outflow from the pen tip and the degree of blurring of handwriting were examined. The test results are shown in Table 2.

[0013]

[Table 2]

The contents of the symbols in the table are as follows. Whitening of handwriting ○: No whitening is observed ×: Whitening phenomenon occurs and the projected characters are darkened Ink outflow ○: Good ink outflow ×: Ink outflow is poor and handwriting is faint

[0015]

INDUSTRIAL APPLICABILITY The water-based ink of the present invention is applied to a marking pen to give a transparent handwriting without a whitening phenomenon on the surface of a transparent plastic sheet for OHP, and even if it is continuously written, a good ink from the pen tip is obtained. Shows runoff and forms a clean handwriting.

Claims (1)

[Claims] 1. A polymerization degree of 100 to 600 and a saponification degree of 75.
For overheads in which a water-soluble dye is dissolved in an aqueous vehicle containing a polyvinyl acetal resin, which is an acetalization product (acetalization degree of 1 to 30 mol%) of an aldehyde having 1 to 4 carbon atoms of polyvinyl alcohol of 1 mol% or more Water-based marking pen ink.