WO2007004629A1

WO2007004629A1 - Water-erasable ink composition

Info

Publication number: WO2007004629A1
Application number: PCT/JP2006/313269
Authority: WO
Inventors: Norihiro Yamaguchi; Chizuko Kakimoto
Original assignee: Sakura Color Products Corporation
Priority date: 2005-07-06
Filing date: 2006-07-04
Publication date: 2007-01-11
Also published as: JP2007016095A; JP4909536B2

Abstract

The invention provides a water-erasable ink composition capable of giving writing which has clear developed color and which can be erased with water without remaining pale colored stains unlike that of conventional ink. A spontaneously erasable ink composition which comprises the following components based on the whole ink composition, wherein the desensitizer is at least one compound selected from the group consisting of quaternary ammonium salts, pyridinium salts, imidazolium salts and alkylamine/ethylene oxide adducts: i) leuco dye 0.1 to 5wt% ii) developer 0.2 to 20wt% iii) desensitizer 0.2 to 20wt% iv) water-soluble resin 1 to 20wt% v) organic solvent the balance

Description

Specification

Water erasable ink composition

Technical field

[0001] The present invention relates to a water-erasable ink composition capable of clearly coloring handwriting and erasing the colored handwriting with water.

Background art

[0002] Conventionally, various water-erasable ink compositions that can erase handwriting with water using a leuco dye and a developer have been provided (Patent Documents 1 to 15). That is, after coloring or coating with a developer using an ink containing this lipo-dye and applying water to the handwriting, the developer dissolves in water and dissolves in water. It is an ink composition that erases when the developer is released and the leuco dye returns to its original colorless structure.

[0003] Examples of the developer include various water-soluble developers, such as water-soluble thiocyanate metal salts such as zinc salts, cobalt salts, and nickel salts, zinc salicylate, gallic acid, and polyoxyalkylene monoallyl monomethyl. Ether z Maleic anhydride Z Styrene copolymer, Polyoxyethylene alkyl etherified carboxylic acid, Polyoxyethylene aryl ether phosphate, Polyoxyethylene alkyl ether phosphate, p-sulfosalicylic acid, P-toluenesulfonic acid , Naphthalenesulfonic acid, lactic acid, tartaric acid, citrate and the like. In addition, bisphenol A and bisphenol nore S can be displayed in column f as water-insoluble developers.

[0004] Patent Document 1: JP-A-49 109108

Patent Document 2: JP-A-53-82507

Patent Document 3: JP-A-4-85374

Patent Document 4: JP-A-4-239064

Patent Document 5: Patent 2982245

Patent Document 6: Patent 2511838

Patent Document 7: Patent 3329505 Patent Document 8: JP-A-7-90213

Patent Document 9: Patent 35133227

Patent Document 10: JP-A-8-239615

Patent Document 11: JP-A-9-59547

Patent Document 12: JP-A-9 302295

Patent Document 13: JP-A-10-17814

Patent Document 14: Japanese Patent Laid-Open No. 10-101982

Patent Document 15: JP-A-10-130553

[0005] However, in these conventional water erasable ink compositions, even when the handwriting is erased with water, some colored marks may remain.

Disclosure of the invention

Problems to be solved by the invention

[0006] An object of the present invention is to provide a water-erasable ink composition in which the color of a handwriting is clear and when the handwriting is erased with water, a slightly colored mark is not left as in the prior art. .

Means for solving the problem

[0007] As a result of intensive studies on the cause of the color residue after erasing with water in order to solve the above problems, it is difficult to release the dye power by simply attaching water to the handwriting. Got a look. Based on this knowledge, the present invention employs a water erasable ink composition containing a leuco dye, a water-soluble developer, a desensitizer, a water-soluble resin and an organic solvent. As a preferred desensitizing agent, one or more compounds that can be selected from quaternary ammonium salts, pyridinium salts, imidazolium salts, and alkylamine amine oxide adducts were adopted.

The invention of claim 1 is a water erasable ink composition comprising a leuco dye, a water-soluble developer, a desensitizer, a water-soluble rosin and an organic solvent. The invention of claim 2 is characterized in that the desensitizer is one or more compounds selected from the group strength of quaternary ammonium salt, pyridi-um salt, imidazolium salt, alkylamine 'ethylene oxide adduct. The water-erasable ink composition according to claim 1.

[0008] It should be noted that the desensitizer is less than the total amount of the ink composition relative to the leuco dye and the water-soluble developer. 0.2 to 20% by weight, preferably 0.5 to 10% by weight, more preferably 0.2 to 20% by weight with respect to 0.2 to 20% by weight, and even more preferably 0.2 to 20% by weight. It is preferable to contain 5 to 10% by weight. By adjusting the content of the above desensitizer within the range of 0.2 to 20% by weight, preferably 0.5 to 10% by weight, the complementary erasing performance for water erasability is improved.

[0009] In order to increase the initial color density, one or more organic acids selected from the group of sulfone developers, particularly p-toluenesulfonic acid, sulfosalicylic acid and naphthalenesulfonic acid are used as the developer. I prefer to use it.

[0010] Further, since the ink of the present invention is a composition containing a water-soluble resin, water erasability is good.

The invention's effect

[0011] Thereby, when writing using the ink composition of the present invention, since it is an ink composition containing a desensitizer, compared with an ink composition containing no desensitizer, Improved erasability when water is attached to the handwriting. In addition, the composition of the present invention showed a desensitizing action when water containing a desensitizing agent was attached when water containing a desensitizing agent was developed. Thus, after writing ink containing the above raw materials and wiping with a sponge containing water, it will be easier to erase with water without leaving a color residue as before, and exhibits excellent water erasability be able to.

BEST MODE FOR CARRYING OUT THE INVENTION

[0012] Examples of the leuco dyes used in the present invention include triphenylmethane, fluorane, sulrane, indolylphthalide, rhodamine ratata, leucooramine, and the like. It is not particularly limited.

The leuco dye can be contained in an amount of 0.1 to 5% by weight based on the total amount of the ink composition, and the preferred content is 0.5 to 3% by weight. If it exceeds 5% by weight with respect to the total amount of the above leuco dye strength ink composition, it is difficult to dissolve in the ink composition, and if it is less than 0.1% by weight, the color density is too thin. Is scarce.

The developer used in the present invention is not limited to zinc salicylate, gallic acid, polyoxyalkylene monoallyl monomethyl ether Z maleic anhydride Z styrene Copolymer, polyoxyethylene alkyl etherified carboxylic acid, polyoxyethylene aryl ether phosphate, polyoxyethylene alkyl ether phosphate

, P Water-soluble color developers such as sulfosalicylic acid, P-toluenesulfonic acid, naphthalenesulfonic acid, lactic acid, tartaric acid, and citrate can be used. These can be used alone or in combination of two or more.

[0014] From the viewpoint of initial color development, an organic acid having a sulfone group, particularly a water-soluble organic acid having a sulfone group is preferable. Specific examples include p-toluenesulfonic acid, sulfosalicylic acid, naphthalenesulfonic acid, etc. In the present invention, the water-soluble developer is selected from the group of p-toluenesulfonic acid, sulfosalicylic acid and naphthalenesulfonic acid. It is preferred to use one or more organic acids.

[0015] The color developer may be contained in an amount of 0.2 to 20% by weight based on the total amount of the ink composition, and a preferable content is 0.5 to LO weight%. When the developer exceeds 20% by weight with respect to the total amount of the ink composition, the erasability with time decreases, and when it is less than 0.2% by weight, the color density is low and the initial color developability of the handwriting immediately after writing is poor.

[0016] The developer is preferably contained in an amount of 0.2 to 20% by weight based on 0.1 to 5% by weight of the leuco dye in the total amount of the ink composition.

[0017] Examples of the desensitizer used in the present invention include aliphatic ammine salts, quaternary ammonium salts, vanzarconium salts, biridinium salts and imidazolium salts. An ink composition containing a desensitizing agent selected by the manufacturer is preferred. In addition, alkylamines with ethylene oxide such as polyoxyethylene alkylamine are preferred.

Specifically, sodium lauryl trimethyl ammonium, polyoxyethylene stearyl amine, 2-chloro-1,3-dimethyl imidazolium chloride, and cetyl pyridinium chloride are preferable.

[0018] The desensitizer is 0.2 to 20% by weight, preferably 0.5 to 10% by weight, more preferably 0.2 to 20% by weight of the developer, based on the total amount of the ink composition. It is preferable to include 0.2 to 20% by weight, and more preferably 0.5 to 10% by weight.

[0019] A water-soluble rosin can be used in the present invention. For example, polyvinyl pyrrolidone, cellulose-based rosin can be used. Specifically, polypyrrole pyrrolidone, hydroxypropyl Rucellulose can be preferably used. By forming a film using the water-soluble resin in the ink composition of the present invention, nodding when the organic solvent remains in the handwriting is prevented, and the resin itself is water-soluble. Improves water erasability.

[0020] The water-soluble rosin can be contained in an amount of 1 to 20% by weight based on the total amount of the ink composition, and a preferable content is 2 to LO weight%. Containing 1% by weight or more improves the erasability with water. When the water-soluble rosin exceeds 20% by weight based on the total amount of the ink composition, it is difficult to erase with water.

[0021] The organic solvent used in the present invention can be arbitrarily selected, but is preferably selected in consideration of the solubility of leuco dye and other components and the drying speed of the handwriting. Volatile organic solvents are preferred. Examples include alcohol, cellosolve ^ glycol ether, ester, and the like. Specifically, isopropyl alcohol, butanol, propylene glycol monomethyl ether, or the like can be used. The organic solvent can be blended as the remaining component (remainder) content in the ink composition.

[0022] As the wetting agent, polyethylene glycol, glycerin, propylene glycol, and the like can be combined.

Example

[0023] In the compositions shown in Table 1 below, a leuco dye, a developer, a water-soluble rosin and a desensitizer are added to an organic solvent, and dissolved by stirring to obtain ink compositions according to Examples and Comparative Examples. Got.

[0024] [Table 1]

Next, each ink composition of the above examples and comparative examples is filled into a core made of a polyester fiber bundle, and a marking pen is prepared. The water erasability immediately after writing and the water erasability 1 day after writing were evaluated. [0026] <Evaluation>

(Initial color development immediately after writing)

The state of color development was confirmed visually.

〇: Clearly colored immediately after writing

X: Coloring after writing and after solvent evaporation

[0027] (Water erasability immediately after writing)

Write on an enamel whiteboard.

After writing, erase the handwriting with a cloth soaked in water.

○: Clearly erased

△: A part of the handwriting remains

X: Not erased

(Water erasability after 1 day of writing)

Written one day after writing, erase the handwriting with a cloth soaked in water.

○: Clearly erased

△: A part of the handwriting remains

X: Not erased

[0028] From Table 1, no desensitizer is included! /, In contrast to the comparative example, the inks of the examples containing the desensitizer all have good water erasability after writing.

Industrial applicability

[0029] The present invention can be used for an ink composition for white plate or drawing sheet that can erase handwriting with water or a sponge or cloth containing water, an ink for marking pen, and the like.

Claims

The scope of the claims

[1] A water erasable ink yarn composition comprising a leuco dye, a water-soluble developer, a desensitizer, a water-soluble resin and an organic solvent.

[2] The water erasable ink composition according to claim 1, wherein the desensitizer is one or more compounds selected from the group strength of quaternary ammonium salt, pyridinium salt, imidazolium salt, alkylamine 'ethylene oxide adduct. object.

[3] The water-erasable ink composition according to claim 1 or 2, wherein the desensitizer is contained in an amount of 0.2 to 20% by weight based on the total amount of the ink composition.

[4] The developer according to any one of claims 1 to 3, wherein the developer is one or more organic acids selected from the group power of p-toluenesulfonic acid, sulfosalicylic acid and naphthalenesulfonic acid. Water erasable ink composition.

[5] A time-erasable ink composition containing the following components based on the total amount of the ink composition.

i) Leuco dye 0.1 to 5% by weight

ii) Developer 0.2 to 20% by weight

iii) Desensitizer 0.2 to 20% by weight

iv) 1-20% by weight of water-soluble fat

V) Organic solvent balance

[6] A writing instrument using the ink composition according to any one of claims 1 to 5.