TW201400560A - Dye, microcapsule pigment using same, and ink composition for writing utensils - Google Patents

Abstract

Provided are: a dye which has excellent developed color density and excellent light resistance; a microcapsule pigment using this dye; and an ink composition for writing utensils. A microcapsule pigment which contains at least a dye that is characterized by being formed of a leuco dye represented by formula (I), a developer and a color change temperature regulator; and an ink composition for writing utensils, which is characterized by containing this microcapsule pigment. (In formula (I), each of X and Y represents a hydrogen atom, an alkyl group having 1-4 carbon atoms or a halogen atom, and X and Y may be the same as or different from each other, provided that X and Y are not hydrogen atoms at the same time; and Z represents an ethyl group or a butyl group.)

Description

Pigment, ink composition using the microcapsule pigment and writing utensil

The present invention relates to a dye, a microcapsule pigment using the same, and an ink composition for a writing instrument, and more specifically, a coloring matter composed of a colorless dye excellent in color development density and light resistance, and color development using the coloring matter. A thermochromic microcapsule pigment of a color erasing mechanism, and an ink composition for a writing instrument containing the microcapsule pigment.

In the past, an ink composition for writing utensils using a coloring agent using a colorless coloring and a color-changing agent of a color erasing mechanism has been used, and a pigment obtained by microencapsulating the above pigment is usually used.

It is known that, for example, a specific fluoran type of electron-donating color-developing organic compound, an electron-accepting compound of a color developing agent, (reference) is made in a specific temperature region due to the aforementioned two A reversible thermochromic microcapsule pigment obtained by reversibly causing a reaction medium in which an electron is subjected to a reaction is contained in a microcapsule (see, for example, Patent Document 1), and a specific pigment (compound) in the paragraph [0005] of the document 1 Listed are many fluorans.

However, the color development density and light resistance of the fluorines described in the above-mentioned Document 1 are not sufficient, and the concentration of the microcapsule pigment and the writing instrument ink is insufficient, and there is a problem that the color is faded when the line is drawn. .

[Previous Technical Literature] [Patent Literature]

Patent Document 1: JP-A-2002-294096 (Application Patent Range, Examples, etc.)

The present invention has been made in view of the above problems and the current state of the art, and aims to solve the above problems. The object of the present invention is to provide a coloring matter made of a colorless dye having excellent color development density and light resistance, and to develop color and color by using the coloring matter. A thermochromic microcapsule pigment excellent in color development and color erasing of an institution, and an ink composition for writing utensils containing the microcapsule pigment.

As a result of active research, the present inventors have found that a specific colorless dye is obtained by using a microcapsule pigment using the pigment, and a microcapsule pigment and a writing implement using the same are used. The ink composition thus completes the present invention.

That is, the present invention has the following (1) to (4).

(1) A pigment characterized by consisting of a colorless dye represented by the following formula (I), [X, Y in the above formula (I) represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms or a halogen atom, and these may be the same or different from each other, except that X and Y are each a hydrogen atom. And Z represents an ethyl group or a butyl group].

(2) The dye according to the above (1), wherein at least one of X and Y in the above formula (I) is a methyl group or a chlorine atom.

(3) A microcapsule pigment characterized by containing at least the dye, the color developer, and the color change temperature adjusting agent according to the above (1) or (2).

(4) An ink composition for a writing instrument, comprising the microcapsule pigment according to the above (3).

According to the present invention, there is provided a coloring pigment which is excellent in color development density and light resistance, and a thermochromic microcapsule pigment which is excellent in color development and color erasing property by using the color development of the coloring matter and color erasing mechanism. And an ink composition for writing utensils containing the microcapsule pigment.

Hereinafter, embodiments of the present invention will be described in detail.

[pigment]

The pigment of the present invention is characterized by being a colorless dye represented by the following formula (I).

[X, Y in the above formula (I) represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms or a halogen atom, and these may be the same or different from each other, except that X and Y are each a hydrogen atom. And Z represents an ethyl group or a butyl group].

The coloring matter represented by the above formula (I) used in the present invention is excellent in color development density and light resistance of a black colorless dye, and is a black color pigment having a high concentration.

The leuco-forms and the like exemplified in Patent Document 1 are known as the colorless dyes of the black color. However, in the present invention, by using the dye represented by the above formula (I), it is more excellent in color development density and light resistance, and black having a higher concentration. By.

X and Y in the above formula (I) are a carbon number consisting of methyl, ethyl, n-propyl, isopropyl, n-butyl, t-butyl, isobutyl, t-butyl and the like. An alkyl group of ~4, or a fluorine atom (-F), a chlorine atom (-Cl), a bromine atom (-Br), an iodine atom (-I), or the like.

In the above formula (I), X and Y are a hydrogen atom or a methyl group or an ethyl group. An alkyl group having 1 to 4 carbon atoms, or a fluorine atom (-F) or a chlorine atom (-) composed of n-propyl, isopropyl, n-butyl, t-butyl, isobutyl, t-butyl or the like Cl), a bromine atom (-Br), an iodine atom (-I), etc., which may be the same or different from each other. However, except when X and Y are both hydrogen atoms. Further, Z represents an ethyl group or a butyl group.

Specific leuco dyes represented by the above formula (I) can be exemplified by, for example, 6-methyl-2'-anilino-3'-methyl-6'-N,N-diethylamino fluoran, 7- Methyl-2'-anilino-3'-methyl-6'-N,N-diethylamino fluoran, 6-ethyl-2'-anilino-3'-methyl-6'- N,N-diethylamino fluorane, 7-ethyl-2'-anilino-3'-methyl-6'-N,N-diethylamino fluoran, 6-chloro-2'-anilino-3'-methyl-6'-N,N-diethylamino fluoran, 7-chloro-2'-anilino-3'-methyl-6'-N,N-diethyl Amino fluorinated, 6-fluoro-2'-anilino-3'-methyl-6'-N,N-diethylamino fluoran, 7-fluoro-2'-anilino-3'- Methyl-6'-N,N-diethylamino fluoran, 6-bromo-2'-anilino-3'-methyl-6'-N,N-diethylamino fluoran, 7 -Bromo-2'-anilino-3'-methyl-6'-N,N-diethylamino fluoran, 6-iodo-2'-anilino-3'-methyl-6'-N , N-diethylamino fluoran, 7-iodo-2'-anilino-3'-methyl-6'-N,N-diethylamino fluoran, 6-methyl-2'- Anilino-3'-methyl-6'-N,N-dibutylamino fluorane, 7-methyl-2'-anilino-3'-methyl-6'-N, N-dibutyl Amino fluorinated, 6-ethyl-2'-anilino-3'-methyl-6'-N,N-dibutylamino fluorane, 7-ethyl-2'-benzene -3'-methyl-6'-N,N-dibutylamino fluorane, 6-chloro-2'-anilino-3'-methyl-6'-N,N-dibutylamine Sulphoxane, 7-chloro-2'-anilino-3'-methyl-6'-N,N-dibutylamino fluorane, 6-fluoro-2'-anilino-3'-methyl -6'-N,N-dibutylamino fluorane, 7-fluoro-2'-anilino-3'-methyl-6'-N,N-dibutylamino fluoran, 6-bromo -2'-anilino-3'-methyl-6'-N,N-dibutylamino fluorane, 7-bromo-2'-anilino-3'-methyl-6'-N,N -dibutylamino fluorane, 6-iodo-2'-anilino-3'-methyl-6'-N,N-dibutylamino fluorane, 7-iodo-2'-anilino- 3'-Methyl-6'-N,N-dibutylamino fluorane, 6,7-dichloro-2'-anilino-3'-methyl-6'-N,N-diethyl Amino fluorane, 6,7-difluoro-2'-anilino-3'-methyl-6'-N,N-diethylamino fluoran, 6,7-dibromo-2'-aniline -3'-methyl-6'-N,N-diethylamino fluoran, 6,7-diiodo-2'-anilino-3'-methyl-6'-N, N-di Ethylamino fluorane, 6,7-dichloro-2'-anilino-3'-methyl-6'-N,N-dibutylamino fluorane, 6,7-difluoro-2'-anilino-3'-methyl-6'-N,N-dibutylamino fluorane, 6,7-dibromo-2'-anilino-3'-methyl-6'-N,N -dibutylamino fluorane, 6,7-diiodo-2'-benzene -3'-methyl -6'-N, N- dibutyl firefly alkoxy group and the like, these may be used or in combination of two or more. Preferably, Z is an ethyl group or a butyl group, and at least one of X and Y is a methyl group (-CH ₃ ) or a chlorine atom (-Cl) from the viewpoints of color development density, light resistance, and manufacturability. ) is better. By introducing the above-mentioned groups, high concentration and excellent light resistance can be achieved. More preferably, both X and Y are halogen atoms, and in particular, the chlorine atom (-Cl) can further improve light resistance.

The production of each of the leuco dyes represented by the above formula (I) can be carried out by heating a triarylamine derivative and a phthalic anhydride derivative obtained by a commercially available or widely used synthetic means in the presence of an acid catalyst. Further, a colorless dye excellent in the color development density and light resistance represented by the above formula (I) can be easily obtained.

[microcapsule pigment]

Next, the microcapsule pigment of the present invention is contained at least by the above formula ( I) A thermochromic composition composed of a pigment, a color developer, and a color change temperature adjusting agent.

<Reagent>

The developer to be used is a component having the ability to develop the pigment represented by the above formula (I). The coloring agent to be used may be, for example, a mineral acid, an aromatic carboxylic acid, an acid anhydride or a metal salt thereof, an organic sulfonic acid, another organic acid, or a phenolic compound.

Preferably, it is a bisphenol derivative, and it is represented by the compound of the following formula (II).

[R1 in the above formula (II) represents a hydrogen atom or an alkyl group having 1 to 2 carbon atoms, and R2 represents a linear or branched alkyl group having 4 to 10 carbon atoms].

A sulfonyl urea compound can also be preferably used in addition to the above.

Specific examples of the compound of the above formula (II) are 4,4'-(2-ethylhexylene)bisphenol, 4,4'-(2-ethylpentylene)bisphenol, 4,4' - octyl bisphenol, 4,4'-hexamethylene bisphenol, 4,4'-(4-methyl octylene) bisphenol, 4,4'-fluorenylene bisphenol, 4,4'- (1,3-dimethylbutylene) bisphenol, 4,4'-(3-methylbutylidene)bisphenol, 4,4'-(1-methylheptylene)bisphenol, 4,4 '-(1,2-dimethylbutylene)bisphenol, 4,4'-(1,5-dimethylhexylene)bisphenol, 4,4'-(1-ethyl-3-methyl Pentylene)bisphenol, 4,4'-( 1-methyl-4-methylpentylene)bisphenol, 4,4'-(1-ethyl-hexylene)bisphenol, 4,4'-(1-ethyl-pentylene)bisphenol At least one of 4,4'-(1-ethyl-octylene) bisphenol (each of a mixture of two or more, the same applies hereinafter) is of course not limited thereto.

When one or a combination of two or more of these developers is used in the present invention, or in a range that does not impair the characteristics of the developer of the present invention, it is freely combinable by combining a conventional developer. Adjust the color density when the color is displayed. Therefore, the amount of use is not particularly limited as long as it is arbitrarily selected depending on the desired color density. However, it is usually in the range of about 0.1 to 100 parts by mass based on 1 part by mass of the dye represented by the formula (I). Internal selection.

<Color change temperature adjuster>

The color change temperature adjusting agent used in the present invention is a substance which controls the color change temperature in the color of the coloring matter represented by the above formula (I) and the color developing agent.

The color change temperature adjusting agent which can be used can be used by a conventional one, and specifically, an alcohol, an ester, a ketone, an ether, an acid amide, an azomethane, a fatty acid, a hydrocarbon, etc. are mentioned.

The ester compound having a hydroxyl group in a chemical structure and a saturated fatty acid having 8 to 22 carbon atoms is preferably an ester compound composed of a bisphenol derivative and a saturated fatty acid having 8 to 22 carbon atoms, for example. The formula (III) is as follows.

[R3 and R4 in the above formula (III) represent a linear or branched alkyl group having 7 to 21 carbon atoms, and R5 and R6 represent a hydrogen atom, an alkyl group having 1 to 2 carbon atoms, or CF ₃ ].

The compound of the above formula (III) is specifically exemplified by 4,4'-(hexafluoroisopropylidene)bisphenol dihexanoate, 4,4'-(hexafluoroisopropylidene)bisphenol dilaurate Ester, 4,4'-(hexafluoroisopropylidene)bisphenol dimyristate, 4,4'-(hexafluoroisopropylidene)bisphenol dipalmitate, 4,4'-(six Fluoroisopropylidene)bisphenol di-undecanoate, 4,4'-(hexafluoroisopropylidene)bisphenol ditridecanoate, 4,4'-(isopropylidene) Bisphenol dihexanoate, 4,4'-(isopropylidene)bisphenol dilaurate, 4,4'-(isopropylidene)bisphenol dimyristate, 4,4'-( Isopropyl)bisphenol dipalmitate, 4,4'-(isopropylidene)bisphenol di-undecanoate, 4,4'-(isopropylidene)bisphenol di- thirteen Alkanoate, 4,4'-methylene bisphenol dihexanoate, 4,4'-methylene bisphenol dilaurate, 4,4'-methylene bisphenol dimyristate, 4,4'-methylene bisphenol dipalmitate, 4,4'-methylene bisphenol di-undecanoate, 4,4'-methylene bisphenol di-tridecanoate Wait for at least one.

The amount of use of the color change temperature adjusting agent is not particularly limited as long as it is appropriately selected depending on the desired hysteresis width and the color density at the time of color development, but is usually preferably 1 in terms of 1 part by mass of the dye. It is used in a range of ~1000 parts by mass.

Further, as long as the properties of the composition of the present invention are not impaired, a conventional color change temperature adjusting agent may be used in combination.

<microcapsule pigment>

The microcapsule pigment used in the present invention can be formed by at least the dye, the color developer, and the color change temperature adjusting agent represented by the above formula (I), so that the average particle diameter is preferably 0.3 to 1.0 μm . The thermochromic composition is produced by microencapsulation.

The microencapsulation method may, for example, be an interfacial polymerization method, an interfacial polycondensation method, an in situ polymerization method, a liquid hardening coating method, a phase separation method from an aqueous solution, a phase separation method from an organic solvent, and a melt dispersion cooling method. The method, the suspension coating method in the gas, the spray drying method, etc., may be appropriately selected depending on the use.

For example, the phase separation method from the aqueous solution can be heated and melted by the dye, the color developer, and the color change temperature adjusting agent represented by the above formula (I), and then placed in an emulsifier solution, and dispersed by heating and stirring to form an oil droplet. Using a resin material or the like as a capsule film, for example, slowly introducing an amine-based resin solution, specifically, a liquid such as a methylol melamine aqueous solution, a urea solution, or a benzopyrene solution, and continuing to react and modulate the dispersion. And a thermochromic microcapsule pigment for the purpose of manufacture.

The content of the coloring matter, the coloring agent, and the color change temperature adjusting agent varies depending on the type of the dye represented by the above formula (I), the color developing agent, the color change temperature adjusting agent, the microencapsulation method, and the like. The coloring matter 1 is 0.1 to 100 in terms of a mass ratio, and the color temperature adjusting agent is 1 to 100. Further, the capsule film is 0.1 to 1 in terms of a mass ratio with respect to the contents of the capsule.

The microcapsule pigment of the present invention can be set to a preferred temperature by appropriately combining the type, amount, and the like of the coloring matter, the color developing agent, and the color change temperature adjusting agent represented by the above formula (I). .

The microcapsule pigment of the present invention is preferably formed of a urethane resin, an epoxy resin, or an amine-based resin in terms of line density, storage stability, and further improvement in writing property. As the urethane resin, a compound such as an isocyanate and a polyhydric alcohol is exemplified. The epoxy resin is exemplified by a compound such as an epoxy resin and an amine. The amine-based resin is preferably formed of, for example, a melamine resin, a urea resin, a benzofluorene resin, or the like, and is preferably formed of a melamine resin in terms of manufacturability, storage stability, and writing property.

The thickness of the wall film of the microcapsule pigment is appropriately determined depending on the desired wall film strength or the concentration of the line.

Further, in order to form a wall film of an amine-based resin, when each microencapsulation method is used, an appropriate amine-based resin raw material (melamine resin, urea resin, benzopyrene resin, or the like), a dispersant, a protective colloid, or the like is selected.

The average particle diameter of the microcapsule pigment used in the present invention is preferably from 0.3 to 1.0 μ in terms of coloring property, color development property, easy color erasability, stability, and suppression of adverse effects on writing properties. m. In addition, the "average particle diameter" defined in the present invention (including the examples and the like) is a particle size distribution measuring device [particle size measuring device N4Plus (manufactured by COULTER)], and the value of the average particle diameter is measured.

When the average particle diameter is less than 0.3 μm , a sufficient trace concentration cannot be obtained. On the other hand, when it exceeds 1.0 μm , the writing property is deteriorated or the dispersion stability of the microcapsule pigment is lowered, which is not preferable.

Further, the average particle diameter of the above range becomes (0.3 ~ 1.0 μ μm) of the microcapsule pigment, although based on microencapsulation method varies, but by the phase separation method from an aqueous solution of the other, preferably when producing microcapsule pigment composition It is prepared by stirring conditions.

The microcapsule pigment of the present invention having such a composition has excellent color development density and light resistance, and is excellent in easy decoloring property and stability, and can be preferably used as a thermochromic pigment for writing utensils, as will be described later. A pigment which is an ink composition of a water-based or oily writing implement can be used, and it is possible to exhibit the above effects without being affected by the type of the solvent or the like.

<Ink composition for writing utensils>

The ink composition for writing utensils of the present invention is characterized in that it contains a microcapsule pigment having the above-described composition, and can be used as an ink composition for writing utensils such as an aqueous or oily steel ballpoint pen or a microphone.

The content of the microcapsule pigment of the present invention is preferably from 5 to 30% by mass (hereinafter abbreviated as "%"), more preferably from 10 to 25%, based on the total amount of each of the aqueous or oily ink compositions.

When the content of the microcapsule pigment is less than 5%, the coloring power and the color development property are insufficient. On the other hand, when it exceeds 30%, the writing breakage tends to be white, which is not preferable.

<Water-based ink composition for writing utensils>

In the ink composition for writing utensils of the present invention, when it is aqueous, Other than the microcapsule pigment, solvent water (tap water, purified water, distilled water, ion-exchanged water, pure water, etc.) is used, and it is not damaged according to the use of each writing instrument (for steel ball pens, microphone pens, etc.). Within the scope of the effects of the present invention, an aqueous organic solvent, a thickener, a lubricant, a rust preventive, a preservative or an antibacterial agent may be appropriately contained.

The water-soluble organic solvent which can be used may be used singly or in combination, for example, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, polyethylene glycol, 3-butanediol, thiodiethylene glycol, glycerin. Ethylene glycols, or ethylene glycol monomethyl ether, diethylene glycol monomethyl ether.

The tackifier which can be used is preferably at least one selected from the group consisting of synthetic polymers, cellulose and polysaccharides. Specifically, it is listed as gum arabic, tragacanth gum, Guar gum, Locust beans, alginic acid, carrageenan, gelatin, xanthan gum, and weilun. Welan gum, succinoglycan, Diutan gum, dextran, methylcellulose, ethylcellulose, hydroxyethylcellulose, carboxymethylcellulose , starch glycolic acid and its salts, propylene glycol alginate, polyvinyl alcohol, polyvinylpyrrolidone, polyvinyl methyl ether, polyacrylic acid and its salts, carboxyvinyl polymer, polyethylene oxide, vinyl acetate and polyethylene Copolymers of pyrrolidone, crosslinked acrylic polymers and salts thereof, non-crosslinked acrylic polymers and salts thereof, styrene-acrylic copolymers and salts thereof, and the like.

Lubricants are listed as fatty acid esters of polyols, high fatty acid esters of sugars, and polyoxyalkylene higher fatty acids which are also used in the surface treatment agent of pigments. Nonionics such as esters and alkyl phosphates, anionics such as alkylsulfonates of higher fatty acid decylamines, alkyl allyl sulfonates, derivatives of polyalkylene glycols or fluorine-based surfactants, Ether-modified polyfluorene and the like. In addition, the rust inhibitors are exemplified by benzotriazole, tolyltriazole, dicyclohexylammonium nitrate, saponin, etc., preservatives or antibacterial agents are listed as phenol, 2-pyridinethiol 1-oxidation Sodium (Omadine), sodium benzoate, benzimidazole-based compounds, and the like.

When the aqueous ink composition of the writing implement is produced, a conventionally known method can be employed, for example, by blending a specific amount of the above microcapsule pigment and each component in the aqueous solution, and stirring and mixing by a mixer such as a homogenizer or a disperser. obtain. Further, coarse particles of the ink composition may be removed by filtration or centrifugation as needed.

<oily ink composition for writing utensils>

When the ink composition for writing utensils of the present invention is oily, it preferably contains the microcapsule pigment of the above composition and contains at least one selected from the group consisting of polypropylene glycol, polytetramethylene glycol, and polyoxypropylene glyceryl ether. Main solvent. By selecting and using the solvent as the main solvent, the microcapsule pigment does not cause agglomeration with time.

As the polypropylene glycol and polytetramethylene glycol to be used, various polymerization degrees can be used. However, from the viewpoint of further exerting the effects of the present invention, polypropylene glycol preferably has a polymerization degree (weight average) of 400 to 700, and polytetramethylene glycol is more preferable. It is good to use a degree of polymerization (weight average) of 500 to 700.

Further, polyoxypropylene propylene diglyceride [POP(n)) used in the present invention Diglyceryl ether] is a compound obtained by adding a polyoxyalkylene group to a hydroxyl group of diglycerin. In the present invention, the addition molar number (n) of the oxypropyl group in the polyoxypropyl glyceryl ether [POP(n) glyceryl ether] is preferably 4 in terms of the effect of the present invention. ~25, better 4~14.

The content of the main solvent is preferably from 50 to 100%, more preferably from 80 to 100%, based on the total amount of the solvent in the ink composition. By setting the content of the main solvent to 50% or more, the occurrence of temporal coagulation can be suppressed as much as possible. Further, a solvent having a property compatible with the main solvent other than the above main solvent, for example, a solvent such as glycerin, diglycerin or propylene glycol may be appropriately contained within the range which does not impair the effects of the present invention.

In addition to the microcapsule pigment and the main solvent, the ink composition for writing instruments can be used for each writing instrument (for steel ball pens, for use with a microphone pen, etc.), and if necessary, does not adversely affect the oily ink. A compatible resin or dispersant, rust inhibitor, preservative, lubricant, and the like.

The resin which can be used is exemplified by, for example, a ketone resin, a styrene resin, a styrene-acrylic resin, a terpene phenol resin, a rosin-modified maleic acid resin, a rosin phenol resin, an alkylphenol resin, a phenol resin, and styrene. A resin represented by a maleic acid resin, a rosin resin, an acrylic resin, a urea aldehyde resin, a maleic acid resin, a cyclohexanone resin, polyvinyl butyral or polyvinylpyrrolidone.

The dispersing agent which can be used can be selected from the above-exemplified resins to disperse the microcapsule pigment, and if necessary, may also contain a surfactant or an oligomer.

Specific dispersing agents can be exemplified by, for example, polyvinyl alcohol and polyvinylpyrrolidine. a synthetic resin such as a ketone, a polyvinyl butyral, a polyvinyl ether, a styrene-maleic acid copolymer, a ketone resin, a hydroxyethyl cellulose or a derivative thereof, a styrene-acrylic acid copolymer, or the like. An EO adduct or an amine-based oligomer of a polyester.

Further, as the rust preventive, the preservative, and the lubricant, various rust preventives, preservatives, and lubricants used in the above aqueous solution can be used.

When the oil-based ink composition for writing utensils is produced, a method known in the past can be used, for example, by blending a specific amount of the above-mentioned microcapsule pigment, and each of the above-mentioned oily components, and using a homomixer or a disperser or the like. Obtained by stirring and mixing. Further, coarse particles of the ink composition may be removed by filtration or centrifugation as needed.

The ink composition for writing utensils of the present invention having such a composition is a water-containing microcapsule pigment containing at least a dye, a coloring agent, and a color change temperature adjusting agent which are excellent in the color development density and light resistance represented by the above formula (I), or When the ink is prepared by writing on a paper surface or the like using a writing instrument such as a steel ball pen body or a microphone pen body in which the ink is mounted, the coagulation or discoloration of the microcapsule pigment over time does not occur, and the handwriting can be well discolored. The ink composition for writing utensils.

Example

Next, the present invention will be described in more detail by way of examples and comparative examples, but the invention is not limited to the following examples and the like. In addition, the "parts" of the following blending units mean the parts by mass.

(Production Example 1: Production of the dye represented by the above formula (I))

45.0 g (0.272 mol) of 3-diethylaminophenol and 46.4 g (0.286 mol) of 4-methylphthalic anhydride were added to toluene, and the mixture was stirred under heating at 102 to 103 ° C for 5 hours. Concentration of the obtained reaction liquid to obtain 4-N,N-diethylamino-2-hydroxy-4'-methyl-2'-carboxybenzophenone and 4-N,N-diethylamino group 15.4 g (0.047 mol) of a mixture of 2-hydroxy-5'-methyl-2'-carboxybenzophenone. This was stirred with a mixture of 9.8 g (0.046 mol) of 3-methyl-4-anilinophenol and 100 g of concentrated sulfuric acid at 10 ° C for 12 hours. Subsequently, excess sodium hydroxide and toluene were added and heated at 60 °C. After separating the toluene layer, 2.5 g of activated carbon was added, followed by heating to 60 ° C. Filter when hot. The filtrate was concentrated under reduced pressure, and the crystallized crystals were filtered and dried to give 6-methyl-2'-anilino-3'-methyl-6'-N,N-diethylamino fluorane and 7- A mixture of methyl-2'-anilino-3'-methyl-6'-N,N-diethylaminofluorene was 13.9 g.

(Production Example 2: Production of the dye represented by the above formula (I))

51.2 g (0.310 mol) of 3-diethylaminophenol and 60 g (0.32 mol) of 4-chlorophthalic anhydride were added to toluene, and the mixture was stirred under heating at 102 to 103 ° C for 2 hours. Concentration of the obtained reaction liquid to obtain 4-N,N-diethylamino-2-hydroxy-4'-chloro-2'-carboxybenzophenone and 4-N,N-diethylamino group- A mixture of 2-hydroxy-5'-chloro-2'-carboxybenzophenone 16.3 g (0.047 mol). A mixture of 10.0 g (0.046 mol) of 3-methyl-4-anilinophenol and 100 g of concentrated sulfuric acid was stirred at 10 ° C for 12 hours. Subsequently, excess sodium hydroxide and toluene were added and heated at 60 °C. After separating the toluene layer, add Add activated carbon 3g, then heat to 60 ° C. Filter when hot. The filtrate was concentrated under reduced pressure, and the crystallized crystals were filtered and dried to give 6-chloro-2'-anilino-3'-methyl-6'-N,N-diethylamino fluorane and 7-chloro- 15.8 g of a mixture of 2'-anilino-3'-methyl-6'-N,N-diethylamino fluoran.

(Production Example 3: Production of the dye represented by the above formula (I))

51.2 g (0.310 mol) of 3-diethylaminophenol and 80 g (0.369 mol) of 3,4-dichlorophthalic anhydride were added to toluene, and the mixture was stirred under heating at 102 to 103 ° C for 2 hours. Concentration of the obtained reaction mixture gave 4-N,N-diethylamino-2-hydroxy-4',5'-dichloro-2'-carboxybenzophenone 18 g (0.047 mol). A mixture of 10.0 g (0.046 mol) of 3-methyl-4-anilinophenol and 100 g of concentrated sulfuric acid was stirred at 10 ° C for 12 hours. Subsequently, excess sodium hydroxide and toluene were added and heated at 60 °C. After separating the toluene layer, 3 g of activated carbon was added, followed by heating to 60 ° C. Filter when hot. The filtrate was concentrated under reduced pressure, and the crystals were crystallized, and then dried to obtain 6,7-dichloro-2'-anilino-3'-methyl-6'-N,N-diethylamino fluorane 16.6 g .

(Microcapsule pigment: A-1~A-6) (Microcapsule pigment: A-1~A-3)

1 part of the coloring matter of each of the dyes obtained in Production Examples 1 to 3 (Table 1 below) as a colorless dye, and 4,4'-(2-ethylhexylene)bisphenol 2 as a color developing agent 24 parts of 4,4'-(hexafluoroisopropylidene)bisphenol dimyristate as a discoloration temperature adjuster was heated to 100 ° C and melted to obtain 27 parts of a homogeneous composition.

A homogeneous hot solution of 27 parts of the composition obtained above was added to the methyl vinyl ether to be used as a protective colloid. Maleic anhydride copolymer resin [GANTREZ AN-179: manufactured by ISP Co., Ltd.] 40 parts of an aqueous solution dissolved in 90 ° C at pH 4 of NaOH, stirred and heated to a diameter of about 0.5 to 1.0 μ. m oil droplets, followed by slowly adding 20 parts of melamine resin (SUMITECH Resin M-3, manufactured by Sumitomo Chemical Co., Ltd.) as a capsule film, and microencapsulation at 90 ° C for 30 minutes to obtain a film agent from melamine A microcapsule dispersion of a reversible thermochromic composition formed by a resin. The hue is a black color in the state of color development, and it becomes a colorless person with no residual color in the achromatic state.

(Microcapsule pigment: A-4)

In the above A-1, except that 4,4'-(1,3-dimethylbutylene) bisphenol is used instead of 4,4'-(2-ethylhexylene) bisphenol as a color developer, and The use of 4,4'-ethylidene bisphenol dilaurate instead of 4,4'-(hexafluoroisopropylidene)bisphenol as the color change temperature adjuster was the same as that of the above A-1. A microcapsule dispersion of a reversible thermochromic composition. The hue is a black color in the state of color development, and it becomes a colorless person with no residual color in the achromatic state.

(Microcapsule pigment: A-5)

In the above A-2, except that 4,4'-isopropylidene bisphenol dimyristate is used instead of the color change temperature adjusting agent used in the above A-2 as a colorless dye, the balance is the same as the above A-2. The same prescription, get reversible temperature change A microcapsule dispersion of a chromatic composition. The hue is thick black in the state of color development, and becomes colorless in the achromatic state.

(Microcapsule pigment: A-6)

In the above A-1, except that 2-(2-chloroanilino)-6-dibutylamino fluorane was used instead of the dye used in the above A-1 as a leuco dye, the balance was the same as the above A-1. The same prescription was obtained, and a microcapsule dispersion of a reversible thermochromic composition was obtained. The hue is black in the state of color development and colorless in the achromatic state.

(Examples 1 to 10 and Comparative Examples 1 and 2) (where the ink is)

According to the formulation shown in Table 2 below (microcapsule pigments: A-1 to A-6, Examples 1 to 5 and Comparative Example 1 are components of aqueous ink, and Examples 6 to 10 and Comparative Example 2 For each component of the oily ink, an aqueous ink composition for each oily ballpoint pen is prepared by a conventional method. Further, each of the microcapsule pigments A-1 to A-6 was used as a microcapsule pigment by filtering each of the microcapsule dispersions and drying them.

(Production of water-based steel ball pen and oil-based steel ball pen)

An aqueous steel ball pen and an oily steel ball pen were produced using each of the ink compositions obtained above. Specifically, a steel ball pen (manufactured by Mitsubishi Pencil Co., Ltd., trade name: SIGNO UM-100) is used, and an ink storage tube made of polypropylene having an inner diameter of 38 mm and a length of 113 mm and a stainless steel nib are used. (Superhard alloy ball, ball diameter 0.5mm) and a supplementary pipe composed of a joint connecting the storage tube and the tip of the pen are filled with the above-mentioned various water-based and oil-based inks, and the ink is filled with an ink containing inorganic oil as a main component at the rear end of the ink. Body, water-based steel ball pen, oily steel ball pen.

Using the obtained steel ball pens of Examples 1 to 8 and Comparative Examples 1 and 2, the light resistance and the line drawing density were evaluated by the following evaluation methods.

These results are shown in Table 2 below.

(Evaluation method of light resistance)

Will be melamine. The formaldehyde condensate was added to the dispersion of the above microcapsules to adjust the pigment concentration to 15% by mass. For the obtained dispersion, an eccentric applicator (manufactured by 10 MIL/UESHIMA SEISAKUSHO Co., Ltd.) was used to develop color on a white phase paper. The light resistance was evaluated on the basis of the following criteria. For this, a XENON light resistance tester X25F (FLR40SW/M/36, manufactured by Suga Test Machine Co., Ltd.) was irradiated for 30 and 50 hours to color computer (SC-P manufactured by Suga Test Machine Co., Ltd.). The L value (lightness) before and after the irradiation was measured, and the L value after the irradiation/the L value before the irradiation was evaluated. Further, the measurement conditions were regular reflection light: except for the light source field of view: D65/10.

Evaluation criteria:

○: 1.0~1.1

△: more than 1.1~ not up to 1.2

×: more than 1.2

(Method for evaluating the concentration of the line)

According to the ISO standard, each pen body was written on a writing paper by a FREE HAND spiral, and the threading concentration was visually evaluated based on the following criteria.

Evaluation criteria:

○: The color status is rich black

△: The concentration is slightly thinner under the color development state

×: concentration thin in the state of color development

As can be seen from the results of the above-mentioned Tables 1 and 2, the ink compositions for writing instruments of Examples 1 to 10 of the present invention are ink compositions for writing instruments of Comparative Examples 1 and 2 which are different from the range of the present invention. It was found that the dyeing property was excellent and the satisfactory linear concentration was satisfied.

On the other hand, in each of the ink compositions of Comparative Examples 1 and 2 containing 2-(2-chloroanilino)-6-dibutylamino fluorane as a colorless pigment microcapsule pigment, sufficient light resistance could not be obtained. Sex, line concentration.

Industrial useability

The present invention obtains a pigment suitable for a writing instrument such as an oil-based or oil-based steel ballpoint pen or a microphone pen, and uses the microcapsule pigment and the ink composition for writing utensils.

Claims (4)

A pigment characterized by consisting of a colorless pigment represented by the following formula (I), [X, Y in the above formula (I) represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms or a halogen atom, and these may be the same or different from each other, except that X and Y are each a hydrogen atom. And Z represents an ethyl group or a butyl group]. The dye according to claim 1, wherein at least one of X and Y in the above formula (I) is a methyl group or a chlorine atom. A microcapsule pigment characterized by containing at least a pigment, a color developer and a color change temperature adjusting agent according to claim 1 or 2. An ink composition for writing utensils, characterized by containing a microcapsule pigment as in item 3 of the patent application.