JP3163458B2 - Water-based fluorescent ink for marking pens - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is suitable for use as a fluorescent ink for a marking pen for writing a fluorescent color underline in a desired portion of a document, particularly, a thermal paper used for a facsimile or other OA equipment. The present invention relates to a fluorescent ink for a marking pen.

[0002]

2. Description of the Related Art In general, aqueous fluorescing inks for marking pens are blended with glycols, glycerin and other moisturizing water-soluble organic solvents as wetting agents to suppress drying at the pen tip. Aqueous fluorescent inks using fluorescent dyes often use an auxiliary agent that promotes fluorescent coloring.

[0003]

This type of aqueous fluorescent ink for marking pens is often applied to thermal paper. However, the interaction between the wetting agent and the coating components on the thermal paper causes the fluorescent handwriting to darken. Or the printing on the thermal paper is lost. Further, there is a problem that the auxiliary also causes an interaction with a coating component of the thermal paper to darken the fluorescent handwriting or to lose the auxiliary and cause the fluorescent color of the handwriting to become lighter. An object of the present invention is to provide a water-based fluorescent ink for a marking pen that suppresses the discoloration of handwriting on the thermal paper.

[0004]

The aqueous fluorescent ink for a marking pen of the present invention comprises a fluorescent dye or a fluorescent pigment dissolved or dispersed in an aqueous medium, wherein the aqueous medium contains 0.1 to 50% by weight of the total amount of the ink. Glycolic acid, lactic acid, α
-Alkali metal salts of oxybutyric acid, glyceric acid, malic acid, tartaric acid and / or alkali metal pyrrolidone carboxylate. Examples of the fluorescent dye include hydroxytrisulfonic acid (CI solvent green 7), flavin (CI basic yellow 1), acidic flavin (CI acid yellow 7), and rhodamine B (CI basic yellow). Violet 10), rhodamine F4G (CI basic red 1) and the like are used in the ink composition in the range of 1 to 10% by weight. Lumicor series (manufactured by Japan Fluorescent Co., Ltd.), S
W series (manufactured by Shinloich Co., Ltd.) and LM21 series (manufactured by Fuji Dye Co., Ltd.)
It is used in the range of weight%. The components added to suppress discoloration of handwriting on thermal paper are glycolic acid, lactic acid,
α- oxy acid, glyceric acid, malic acid, Li <br/> lithium tartaric acid, a sodium, lithium potassium salt and pyrrolidone carboxylic acid, sodium, one or more selected from potassium, ink In composition, 0.1 to 50
%, Preferably in the range of 1 to 20% by weight. In the aqueous medium, in addition to the above components, 5
Glycerin (wetting agent) of ~ 40% by weight, trace amount of preservative,
If necessary, a fluorescent coloring aid of a fluorescent dye, a surfactant and the like are added, but water accounts for 50% by weight or more of the medium.

[0005]

The aqueous fluorescent ink for a marking pen of the present invention is
Glycolic acid, lactic acid, α-oxy added to ink
The discoloration of the handwriting written on the thermal paper is suppressed by the action of the alkali metal salts of butyric acid, glyceric acid, malic acid, and tartaric acid and / or the alkali metal salts of pyrrolidonecarboxylic acid.

[0006]

EXAMPLES Example inks and comparative example inks having the following compositions were prepared, and a predetermined amount of each sample ink was filled into a pen having a 4 mmφ rod-shaped pen body made of a resin-processed fiber bundle and a pen provided with a fiber-bundle ink occlusion body. To make a sample pen. A sample ink using a fluorescent pigment was prepared by charging an aqueous medium composed of a mixed solution of water, a wetting agent, and the like into a stirred fluorescent pigment dispersion and stirring the mixture until it became sufficiently homogeneous (Example 1). , 2,3
4 and Comparative Examples 1 and 2). A sample ink using a fluorescent dye was prepared by mixing and stirring all components (Examples 5 and 6,
Comparative Examples 3 and 4). Table 1 shows the composition and physical properties of the sample ink.
Shown in

[Table 1] The numerical values of the compositions in the table are all parts by weight, and the contents of the raw material fluorescent pigment liquid are all aqueous dispersions in which the fluorescent pigment is dispersed in water by a surfactant. Details of the contents of each component are as follows. Fluorescent pigment liquid A: trade name Lumicoll NKW-3005
(Nihon Fluorescent Co., Ltd.) Yellow fluorescent pigment 42% by weight, average particle diameter 0.11 μm Fluorescent pigment liquid B: trade name Lumicoll NKW-3007
(Nihon Fluorescent Co., Ltd.) Pink fluorescent pigment 41% by weight, average particle size 0.11 μm Fluorescent dye: trade name EX-630 (Mitsui Toatsu Chemical Co., Ltd.) Yellow fluorescent dye (CI Solvent Green 7) Auxiliary A : Sodium carbonate Auxiliary B: Triethanolamine PCA-Na aqueous solution: 50% sodium pyrrolidonecarboxylate aqueous solution

Next, printed thermal paper (Panafax ultra-high sensitivity UG-0001B4 of Matsushita Electric Transmission Co., Ltd.)
A line was drawn with each sample pen on the print of No. 1, and the state of the color of the handwriting line after one hour and one week was observed in comparison with the line drawn on plain paper. Table 2 shows the results.

[Table 2] The contents of the symbols in the table are as follows. ：: No discoloration was observed, ◇: Slight discoloration, Δ: Discoloration was observed X: Extremely discoloration (however, underlined symbols indicate fading, others indicate darkening)

[0008]

As can be seen from the results in Table 2, when the aqueous fluorescent ink for a marking pen of the present invention is applied to thermal paper, glycolic acid, lactic acid, α-oxybutyric acid, glycerol
The effect of suppressing discoloration is remarkably exhibited as compared with the handwriting of a comparative ink to which no alkali metal salt of acid, malic acid or tartaric acid or alkali metal pyrrolidonecarboxylate is added.

──────────────────────────────────────────────────続 き Continued on front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C09D 11/00-11/20

Claims (1)

(57) [Claims] 1. An aqueous fluorescent ink for a marking pen in which a fluorescent dye or a fluorescent pigment is dissolved or dispersed in an aqueous medium, wherein the aqueous medium is glycolic acid, lactic acid, α
An aqueous solution for a marking pen, comprising an alkali metal salt of oxybutyric acid, glyceric acid, malic acid or tartaric acid and / or an alkali metal pyrrolidone carboxylate in an amount of 0.1 to 50% by weight of the total amount of the ink. Fluorescent ink.