JP2001260538A - Reversible heat-sensitive recording medium, leuco dye/ polymer compound type heat-sensitive recording layer, manufacturing method therefor and urethane resin used therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a reversible heat-sensitive recording medium, which has a favorable image contrast, with which the formation and erase of an image are possible, which is damaged a few even through the repetitive use between coloring and decoloring, and which has an excellent durability and a high humid ity resistance. SOLUTION: In the reversible heat-sensitive recording medium having a reversible heat-sensitive recording layer including a leuco dye, a reversible developer, which colors the leuco dye under heat and then decolors it under re-heat, and a resin matrix, a resin material used in the resin matrix is prepared by dispersing the leuco dye and the reversible developer in a resin consisting of a urethane resin (A) and a polymerizable unsaturated monomer polymer (B).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a resin useful for forming a leuco dye / polymer composite type thermosensitive recording layer capable of recording and erasing information by heating, a reversible thermosensitive recording layer using the resin, and a reversible thermosensitive recording layer using the same. The present invention relates to a production method and a reversible thermosensitive recording medium using the recording layer. Such a recording medium is
Due to repeated use of repeated coloring and decoloring, damage is small, durability is excellent, and moisture resistance is high.

[0002]

BACKGROUND OF THE INVENTION As disclosed in JP-B-43-4160 and the like, a heat-sensitive recording material generally comprises an electron-donating, usually colorless or light-colored leuco dye and an electron-accepting developer on a support. And a heat-sensitive recording layer having a main component, and by heating with a thermal head, a hot pen, a laser beam or the like, the leuco dye and the developer react instantaneously to obtain a recorded image. . Generally, in such a thermosensitive recording material, once an image is formed, it is impossible to erase that portion and return to the state before image formation. I had no choice but to add. For this reason, when the area of the heat-sensitive recording portion is limited, there has been a problem that the recordable information is limited and all necessary information cannot be recorded.

In recent years, reversible thermosensitive recording materials which can be used even when image formation and image erasure are repeatedly performed have been proposed in order to deal with such a problem.
No. 186 describes a thermosensitive recording material composed of a resin matrix and low organic molecules dispersed in the resin matrix. However, in this method, the transparency of the heat-sensitive recording material is reversibly changed by heat energy, so that the contrast between the image forming portion and the non-image forming portion is insufficient. Also, Japanese Patent Application Laid-Open No. 50-8115
In the method described in Japanese Patent Application Laid-Open No. 7-107, since the image to be formed changes in accordance with the environmental temperature, the temperature at which the image forming state and the erasing state are maintained is different. It cannot be held for a period. Further, JP-A-59-120492 describes a method of maintaining an image forming state and an erasing state by maintaining a recording material in a hysteresis temperature range by utilizing a hysteresis characteristic of a color component. This method requires a heating source and a cooling source for image formation and erasing, and has a disadvantage that a temperature region in which an image forming state and an erasing state can be held is limited to a hysteresis temperature region. It is still insufficient for use with

On the other hand, JP-A-2-188294 describes a reversible thermosensitive recording medium composed of a leuco dye and a color-deteriorating agent for heating and decoloring the leuco dye by heating. The color-developing agent is an amphoteric compound having an acidic group for coloring the leuco dye and a basic group for decolorizing the colored leuco dye, and has a coloring effect by an acidic group or a decolorizing effect by a basic group by controlling thermal energy. One is preferentially generated to perform color development and decoloration. However, in this method, it is impossible to completely switch between the coloring reaction and the decoloring reaction only by controlling the heat energy, and since both reactions occur at a certain ratio at the same time, a sufficient coloring density cannot be obtained. Can't do it perfectly. Therefore, sufficient image contrast cannot be obtained. Further, since the decolorizing action of the basic group also acts on the color-developed portion at room temperature, a phenomenon in which the density of the color-developed portion decreases with time cannot be avoided.

Further, Japanese Patent Application Laid-Open No. 5-124360 describes a reversible thermosensitive recording medium which develops and decolorizes a leuco dye by heating, and comprises an organic phosphoric acid compound, an α-hydroxy aliphatic compound as an electron accepting compound. Specific phenol compounds such as carboxylic acids, fatty acid dicarboxylic acids, and alkylthiophenols having an aliphatic group having 12 or more carbon atoms, alkyloxyphenols, alkylcarbamoylphenols, and alkyl gallates are exemplified. However, even with this recording medium, the two problems of low color density or incomplete erasing cannot be solved at the same time, and the temporal stability of the image is not practically satisfactory. As described above, the conventional technology has good image contrast, is capable of forming and erasing an image, and has practically no reversible thermosensitive recording in which the color density does not change even when color formation and decoloration are repeated many times. Material not known.

Further, Japanese Patent Application Laid-Open No. 6-210954 discloses that an image can be formed and erased with good contrast.
A novel reversible developer capable of maintaining a stable image over time in an environment of daily life is exemplified. However, in such a reversible thermosensitive recording material having a reversible thermosensitive recording layer that develops color by heat, its properties such as color developing property, decoloring property and their repeatability are used for resin binders other than the color forming component. It has been recognized that this is also affected by the resin material used, and that there is a practical problem depending on the type of resin material. In other words, the reversible thermosensitive recording material repeats coloring and decoloring in the same place, and the reversible developer particles tend to aggregate due to the heat and pressure at the time of applying heat. There are problems that the density is reduced and the reversible thermosensitive recording layer is deteriorated.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to form an image and to erase the image, to reduce damage even by repeated use of repeated coloring and decoloring, to have excellent durability and high moisture resistance. And a reversible thermosensitive recording medium.

[0008]

Means for Solving the Problems The present inventors have conducted research to solve the above-mentioned problems, and as a result, by using a specific resin as a matrix resin of a leuco dye / polymer composite type thermosensitive recording layer, The inventors have found that such a problem can be solved, and have completed the present invention.

That is, the first aspect of the present invention is a resin used for a leuco dye / polymer composite type thermosensitive recording layer for a reversible thermosensitive recording medium, wherein the resin is a polymerizable non-polymerizable resin. The present invention relates to a leuco dye / polymer composite type resin for a thermosensitive recording layer, which is composed of a polymer (B) of a saturated monomer. The second aspect of the present invention is the first leuco dye / polymer composite type thermosensitive recording of the present invention, wherein the polymer (B) is dispersed in the urethane resin (A) in the form of particles. It relates to a resin for a layer. A third aspect of the present invention is characterized in that the resin is in an aqueous emulsion state containing polymer particles having a core-shell structure or a microdomain structure composed of a urethane resin (A) and a polymer (B). The present invention relates to the first or second leuco dye / polymer composite type thermosensitive recording layer resin of the present invention. The fourth aspect of the present invention is as follows.
The leuco dye / polymer composite type according to any one of the first to third aspects of the present invention, wherein the polymer (B) contains at least one polymerizable unsaturated monomer having a hydrolyzable silyl group. The present invention relates to a resin for a heat-sensitive recording layer. A fifth aspect of the present invention is that another polymer comprising a polymerizable unsaturated monomer (b) having at least one kind of carboxyl group and another polymerizable monomer (c) is further added. The present invention also relates to the resin for a leuco dye / polymer composite type thermosensitive recording layer according to any one of the first to fourth aspects of the present invention. A sixth aspect of the present invention is the resin according to any one of the first to fifth aspects, wherein the resin is substantially incompatible with the leuco dye and / or the reversible developer and forms a phase-separated structure. The present invention relates to a leuco dye / polymer composite type resin for a heat-sensitive recording layer. A seventh aspect of the present invention is a leuco dye obtained by dispersing a leuco dye and a reversible developer in the resin for a leuco dye / polymer composite type thermosensitive recording layer according to any one of the first to sixth aspects of the present invention. The present invention relates to a molecular composite type thermosensitive recording layer. Also, the eighth aspect of the present invention.
Means that the compounding ratio of (leuco dye + reversible developer) / resin is 10
The present invention relates to a seventh leuco dye / polymer composite type thermosensitive recording layer of the present invention, which is characterized in that the ratio is / 90 to 70/30 wt%. A ninth aspect of the present invention relates to a reversible thermosensitive recording medium comprising the leuco dye / polymer composite type thermosensitive recording layer according to any one of the seventh to eighth aspects of the present invention provided on a substrate. The first aspect of the present invention
No. 0 relates to a ninth reversible thermosensitive recording medium of the present invention, wherein a protective layer is provided on the upper surface of the reversible thermosensitive recording layer. An eleventh aspect of the present invention relates to the leuco dye / polymer composite type thermosensitive recording layer resin water emulsion according to any one of the first to sixth aspects of the present invention, and the seventh leuco dye and the reversible developer of the present invention. The present invention relates to a method for producing a leuco dye / polymer composite type thermosensitive recording layer by applying a coating liquid obtained by dispersing in water onto a substrate and then drying the coating liquid.

[0010]

Next, the present invention will be described in more detail with reference to preferred embodiments. FIG. 1 is a configuration diagram of the reversible thermosensitive recording medium of the present invention. 1 is a resin matrix, 2 is leuco dye particles, 3 is a reversible developer particle, 5
Is a base material and 7 is a protective layer.

In a reversible thermosensitive recording medium utilizing a reaction between an electron-donating dye precursor such as a leuco dye and a reversible developer, the reversible developer has a relatively long-chain aliphatic hydrocarbon group. For this reason, there is a problem that the durability of the heat-sensitive recording layer is low. For example, when color development and decoloration are repeated at the same location, the composition is repeatedly exposed to the pressure of the thermal head and a heat source, so that a reversible thermochromic composition (a composition of a leuco dye and a reversible developer, Both of them repetitively react reversibly to develop and decolor.) Agglomeration or the reversible thermosensitive recording layer flows out and the reversible thermosensitive recording layer is likely to be broken.

In the present invention, a resin composed of a urethane resin (A) and a polymer (B) of a polymerizable unsaturated monomer, together with a leuco dye and a reversible developer, is used as a matrix in a reversible thermosensitive recording layer. Used as The main role of the resin matrix in the heat-sensitive recording layer is to prevent the reversible thermochromic composition from aggregating due to repetition of color development and decoloration, and the urethane resin (A) and the polymerizable unsaturated monomer Polymer (B)
By containing the resin composed of the above as a matrix, without impairing the coloring and decoloring characteristics, the durability is improved repeatedly, the life of the recording medium is significantly increased, and the commercial value of the reversible thermosensitive recording medium is also increased. improves.

Although the reason for improving the durability of the reversible thermosensitive recording layer according to the present invention is not sufficiently clear, the urethane resin (A)
The resin composed of the polymer and the polymer (B) of a polymerizable unsaturated monomer greatly contributes to the improvement of the heat resistance and durability of the reversible thermosensitive recording layer, and the adhesive effect inherent in the resin matrix and the reversible heat It is believed that the composition imparts appropriate elasticity and excellent heat resistance at high temperatures without impairing the dispersibility, coloration and decoloring properties of the color forming composition. It is presumed that these characteristics prevent difficulties such as aggregation of particles of the reversible color-forming composition in the reversible thermosensitive recording layer and improve the quality.

The particles of the reversible thermochromic composition are liable to agglomerate due to the effect of the surrounding resin matrix being deformed by the temperature and pressure at the time of application of heat, which leads to a reduction in the chromogenic properties. A resin composed of a simple urethane resin (A) and a polymer (B) of a polymerizable unsaturated monomer, functions as a resin matrix having an appropriate crosslink density and flexibility, and contributes to improvement of heat resistance. It is supposed to do.
As a result, the particles of the reversible thermochromic composition are not affected by the matrix resin, and the reversible developer particles maintain their initial state even after long-term use. The resin used in the present invention is a water-dispersible resin, and is characterized by forming a phase-separated structure substantially incompatible with the leuco dye and the reversible developer.

These resin matrices can be used not only in the reversible thermosensitive recording layer, but also in an anchor layer between the reversible thermosensitive recording layer and the support, or on the upper surface of the reversible thermosensitive recording layer directly or via an intermediate layer. It can also be added to the layer.

Specific examples of the matrix resin composed of the urethane resin (A) and the polymer (B) of a polymerizable unsaturated monomer used in the present invention will be described. In the present specification, “acrylic” monomers and “methacrylic” monomers are collectively referred to simply as “(meth) acrylic” monomers.

Urethane Resins As the urethane resin (A), various urethane resins obtained by the reaction of a polyisocyanate component, a polyol component, and a polyamine component as a chain extender added as needed are used. The urethane resin (A) is
They can be used alone or in combination of two or more.

Examples of the polyisocyanate include aromatic polyisocyanates such as aromatic polyisocyanates and araliphatic polyisocyanates, and non-aromatic polyisocyanates such as alicyclic polyisocyanates and aliphatic polyisocyanates. Examples of the aromatic polyisocyanate include phenylene diisocyanate such as m-phenylene diisocyanate and p-phenylene diisocyanate; tolylene diisocyanate such as 2,4-tolylene diisocyanate and 2,6-tolylene diisocyanate; and diphenylmethane-4,4 '. Diisocyanates, diisocyanates such as 1,5-naphthalene diisocyanate, and polyisocyanates such as triphenylmethane triisocyanate.
As the araliphatic polyisocyanate, for example, 1,
3-xylylene diisocyanate, xylylene diisocyanate such as 1,4-xylylene diisocyanate,
Examples include diisocyanates such as tetramethylxylylene diisocyanate and polyisocyanates such as 1,3,5-triisocyanatemethylbenzene. Examples of the alicyclic polyisocyanate include, for example, isophorone diisocyanate, dicyclohexylmethane-4,4 '
Diisocyanates, diisocyanates such as cyclohexane-1,4-diisocyanate, and polyisocyanates such as 1,3,5-triisocyanatecyclohexane. Examples of the aliphatic polyisocyanate include aliphatic diisocyanates such as 1,6-hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, and lysine diisocyanate, and aliphatic aliphatic isocyanates such as 1,3,6-hexamethylene triisocyanate. And polyisocyanates. These polyisocyanates can be used alone or in combination of two or more. Is included. As the polyisocyanate, a diisocyanate is usually used.
In addition, polyisocyanate is used as an adduct having a terminal isocyanate group, a biuret formed by a biuret reaction, a carbodiimide, a dimer, and a trimer having an isocyanurate structure. May be.

The polyol component includes, for example, polyester polyol; polyether polyol (for example,
Polyethylene glycol, polypropylene glycol,
Polyoxydiols having oxy-alkylene (= _C2-4 ) units such as polyoxytetramethylene glycol; polyester-polyether polyols; polycarbonate polyols (for example, polycarbonate diol); acrylic polyols and the like. The polyester polyol is a hydroxyl group-containing polyester (especially a polyester diol) obtained by reacting a polyhydric alcohol with a polycarboxylic acid or a lower alkyl ester or an acid anhydride thereof, and a polyester derived from a lactone. Good. The polyol components can be used alone or in combination of two or more. As the polyol component, a diol component (for example,
Polyester diol).

For preparing the polyester polyols
Polyhydric alcohols include, for example, aliphatic polyhydric alcohols.
(Eg, ethylene glycol, trimethylene glycol
, Propylene glycol, 1,3-butanediol
, Tetramethylene glycol, hexamethylene glyco
And alkylenes such as neopentyl glycol (= C
_2-10) Diol, diethylene glycol, triethylene
Glycol, polyoxytetramethylene glycol, etc.
Of polyoxy-alkylene (= C_2-4) Glycol,
Portions such as rimethylolpropane and pentaerythritol
Alicyclic polyhydric alcohols (eg, 1,
4-cyclohexane dimethylol, hydrogenated bisphenol
Alicyclic diols such as A), aromatic polyhydric alcohols
[E.g., 2,2-bis (2-hydroxyethylphene)
Nyl) aromatic diols such as propane, etc.]
Can be Polyhydric alcohols can be used alone or in combination.
Can be used together. Polyhydric alcohols are usually
Oars are appropriate.

Examples of the polycarboxylic acid include aliphatic polycarboxylic acids (eg, unsaturated aliphatic dicarboxylic acids such as adipic acid, suberic acid, azelaic acid, sebacic acid and dodecanedicarboxylic acid, and unsaturated acids such as maleic acid). Aliphatic dicarboxylic acid, etc.), alicyclic polycarboxylic acid (e.g., alicyclic dicarboxylic acid such as 1,4-cyclohexanedicarboxylic acid), aromatic polycarboxylic acid (e.g.,
Examples thereof include aromatic dicarboxylic acids such as phthalic acid, terephthalic acid, isophthalic acid, and 1,5-naphthalenedicarboxylic acid, and aromatic polycarboxylic acids such as trimellitic acid. Polycarboxylic acids can be used alone or in combination of two or more. Examples of lactones include β-propiolactone, δ-valerolactone, ε-caprolactone, α, α-dimethyl-β-propiolactone, β-
Ethyl-δ-valerolactone, α-methyl-ε-caprolactone, β-methyl-ε-caprolactone, γ-methyl-ε-caprolactone, 3,3,5-trimethyl-ε
-Caprolactone, γ-valerolactone, propiolactones such as γ-butyrolactone, butyrolactone,
It contains valerolactones, caprolactones, enantholactone, and the like, and may be used alone or in combination of two or more.

The polyamine component as a chain extender includes, for example, ethylenediamine, trimethylenediamine, tetramethylenediamine, pentamethylenediamine, 1,7-diaminoheptane, 1,8-diaminooctane, xylylenediamine, And diamines such as 4,4-diaminocyclohexane, isophoronediamine and phenylenediamine, and polyamines such as triaminopropane.

In the present invention, the urethane resin (A) may be used as an organic solvent solution, an aqueous solution, or an aqueous emulsion. Such an aqueous solution or water-based emulsion may be prepared by dissolving or emulsifying and dispersing the urethane resin (A) using an emulsifier. It may be prepared by introducing an ionic functional group such as an amino group, and dissolving or dispersing the urethane resin using an alkali or an acid.
Such a urethane resin having a free carboxyl group, a sulfonic acid group or a tertiary amino group introduced into a molecule thereof is a polyisocyanate component and a diol having a free carboxyl group, a sulfonic acid group or a tertiary amino group (particularly, (Polymer diol) component. The diol having a free carboxyl group and a sulfonic acid group (particularly, a polymer diol) is, for example, a diol component and a polycarboxylic acid having three or more carboxyl groups or an acid anhydride thereof (for example, pyromellitic anhydride). Reaction with a 4-basic acid anhydride such as an acid) or using dihydroxycarboxylic acid (such as dimethylolpropionic acid) as an initiator,
It can be obtained by a method such as ring-opening polymerization of lactone. In addition, a diol having a tertiary amino group (particularly, a polymer diol) is obtained by ring-opening polymerization of an alkylene oxide or a lactone using an N-alkyl dialkanolamine (eg, N-methyldiethanolamine) as an initiator. .

Such a urethane resin generally does not contain a crosslinking component and is non-reactive. Therefore, it is easy to handle without curing at room temperature. In particular, the stability is high even in an aqueous system such as an emulsion. The urethane resin (A) has a weight average molecular weight of 2,000 to 50.
000, preferably 5,000 to 200,000 can be used.

Polymer of Polymerizable Unsaturated Monomer The polymerizable unsaturated monomer for forming the polymer (B) of the polymerizable unsaturated monomer is, for example, a (meth) acrylic monomer , Aromatic vinyls, unsaturated carboxylic acids, unsaturated sulfonic acids, vinyl esters, halogen-containing vinyls, vinyl ethers (eg, vinyl ethyl ether, etc.), vinyl ketones (eg, methyl vinyl ketone, etc.), vinyl complex Ring compounds (for example, N-vinyl compounds such as N-vinylpyrrolidone and N-vinylimidazole, vinylpyridine and the like), olefin monomers (for example, ethylene and propylene), allyl compounds (for example, allyl such as allyl acetate) And a monomer having a hydrolyzable silyl group. These polymerizable unsaturated compounds can be used alone or in combination of two or more.

The (meth) acrylic monomer includes:
(Meth) acrylates, (meth) acrylamides,
(Meth) acrylonitrile and the like. (Meta)
As the acrylate, an alkyl (meth) acrylate [for example, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, isobutyl (meth) acrylate, t- butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, alkyl lauryl (meth) acrylate (= C _1-18) (meth) acrylate, etc.], cycloalkyl (Meth) acrylate [for example,
Cyclohexyl (meth) acrylate, etc.], aryl (meth) acrylate [eg, phenyl (meth) acrylate, etc.], aralkyl (meth) acrylate [eg, benzyl (meth) acrylate, etc.], hydroxyalkyl (meth) acrylate [eg, 2 Hydroxy-alkyl (= _C2-4 ) (meth) such as -hydroxyethyl, 2-hydroxypropyl (meth) acrylate
Acrylate, etc.], glycidyl (meth) acrylate, dialkylamino-alkyl (meth) acrylate [for example, dialkyl such as 2- (dimethylamino) ethyl (meth) acrylate, 2- (diethylamino) ethyl (meth) acrylate (= C _{1 -4} ) amino-alkyl (= _C2-4 ) (meth) acrylate and the like].

In the above (meth) acrylic monomer, the
(T) Acrylamides include (meth) acrylamide
Do, hydroxyalkyl (meth) acrylamide [eg
For example, N-methylol (meth) acrylamide and other N-
Hydroxy-alkyl (= C _1-4) (Meth) acrylic
Amide, etc.), alkoxyalkyl (meth) acrylamido
[For example, N-methoxymethyl (meth) acrylamido
N-alkoxy (= C_1-4) -Alkyl (= C
_1-4) (Meth) acrylamide, etc.], diacetone (meth
(T) acrylamide and the like.

Preferred (meth) acrylic monomers are
(Meth) acrylate [for example, alkyl (= C _1-18 )
(Meth) acrylate, hydroxy-alkyl (= C
_2-4 ) (meth) acrylate, glycidyl (meth) acrylate, dialkyl (ア ル キ ル C _1-4 ) amino-alkyl (＝ C _2-4 ) (meth) acrylate, etc.), (meth) acrylamides, and the like. preferably an alkyl (= C _2-10) acrylate, alkyl (= C _1-6) methacrylate, hydroxyethyl - alkyl (= C _2-3) (meth) acrylate, glycidyl (meth) acrylate,
Dialkyl (= C _1-3 ) amino-alkyl (= C _2-3 )
(Meth) acrylate and the like.

Examples of the monomer having a hydrolyzable silyl group include (meth) acrylic monomers and monomers having an alkenyl group such as a vinyl group. As the (meth) acrylic monomer having a hydrolyzable silyl group, specifically, 2- (meth) acryloxyethyltrichlorosilane, 3- (meth) acryloxypropyltrichlorosilane, 2- (meth) Acryloxyethylmethyldichlorosilane, 2- (meth) acryloxyethyldimethylchlorosilane, 2- (meth) acryloxyethyltrimethoxysilane, 2- (meth) acryloxyethyltriethoxysilane, 3- (meth) acryloxypropyl Examples thereof include trimethoxysilane, 3- (meth) acryloxypropyltriethoxysilane, and 3- (meth) acryloxypropyltris (2-methoxyethoxy) silane.

Examples of the monomer having a hydrolyzable silyl group and an alkenyl group such as a vinyl group include vinyltrichlorosilane, vinylmethyldichlorosilane, isopropenyltrichlorosilane, isopropenyldimethylchlorosilane and the like; vinyltrimethoxysilane, Vinyltriethoxysilane, vinyldimethoxymethylsilane, vinyldiethoxymethylsilane, isopropenyltrimethoxysilane, isopropenyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, etc .; allyltrichlorosilane, allylmethyldichlorosilane, etc .; allyltrichlorosilane Methoxysilane, vinylphenyltrimethoxysilane, isopropenylphenyltrimethoxysilane, etc .; 3- [2- (allyloxycarbonyl) phenylcarbonyloxy] B pills trimethoxysilane, 3-
[2- (isopropenylmethyloxycarbonyl) phenylcarbonyloxy] propyltrimethoxysilane and the like; 3- (vinylphenylamino) propyltrimethoxysilane, 3- (vinylphenylamino) propyltriethoxysilane and the like; 3- [2- (N-vinylphenylmethylamino) ethylamino] propyltrimethoxysilane, 3- [2- (N-isopropenylphenylmethylamino) ethylamino] propyltriethoxysilane and the like; 2- (vinyloxy) ethyltrimethoxysilane,
3- (vinyloxy) propyltrimethoxysilane, 4
-(Vinyloxy) butyltriethoxysilane, 2-
(Isopropenyloxy) ethyltrimethoxysilane and the like; 3- (allyloxy) propyltrimethoxysilane, 10- (allyloxycarbonyl) decyltrimethoxysilane, 3- (isopropenylmethoxy) propyltrimethoxysilane and the like; 3-[( Examples thereof include (meth) acryloxyethoxy] propyltrimethoxysilane and 3-[(meth) acryloxyethoxy] propyldimethoxymethylsilane; divinyldimethoxysilane, divinyldiethoxysilane, and divinyldi (β-methoxyethoxy) silane.

Examples of the unsaturated carboxylic acids include unsaturated monocarboxylic acids [eg, ethylenically unsaturated monocarboxylic acids such as (meth) acrylic acid and crotonic acid], and unsaturated polycarboxylic acids [eg, maleic acid]. Ethylenically unsaturated polycarboxylic acids such as acids, fumaric acid, itaconic acid and the like and acid anhydrides (such as maleic anhydride) or esters thereof (for example, monoalkyl dicarboxylic acids such as monomethyl maleate and monobutyl maleate) And the like). Preferred unsaturated carboxylic acids are, for example, monocarboxylic acids such as (meth) acrylic acid, polycarboxylic acids such as maleic acid, and acid anhydrides or esters thereof. Examples of the unsaturated sulfonic acids include vinyl sulfonic acids such as styrene sulfonic acid.

Examples of the aromatic vinyls include styrene, α-methylstyrene, vinyltoluene and the like, and styrene is often used. The vinyl esters include, for example, vinyl acetate, vinyl propionate, vinyl versatate (VeoVa and the like) and the like. Examples of the halogen-containing vinyls include vinyl chloride and vinylidene chloride.

Preferred polymers (B) of polymerizable unsaturated monomers include (meth) acrylic monomers [for example,
(Meth) acrylates, etc.], aromatic vinyls (eg, styrene), unsaturated carboxylic acids [eg, (meth) acrylic acid, maleic acid, etc.], vinyl esters (eg, vinyl acetate, etc.), halogens Examples include homo- or copolymers of at least one monomer selected from vinyl-containing compounds (eg, vinyl chloride) and monomers having a hydrolyzable silyl group. In particular, as the polymer (B) of the polymerizable unsaturated monomer, an acrylic resin using a (meth) acrylic monomer [for example, a homopolymer or a copolymer of a (meth) acrylic monomer] A styrene-based resin using aromatic vinyls [eg, a copolymer of styrene and a (meth) acrylic monomer, etc.] or a polymerizable monomer prepared by mixing a monomer having a hydrolyzable silyl group with them. Polymers obtained from the monomer composition are preferred. In particular, when a polymer obtained from a polymerizable monomer composition containing a monomer having a hydrolyzable silyl group is used, it is useful for increasing the heat resistance of the recording display layer and the color density of repetitive recording characteristics.

The weight average molecular weight of the polymer (B) is, for example, 0.2 × 10 ^{4 to} 100 × 10 ⁴ , preferably 1 × 10 ⁴ .
It is in the range of about 10 ⁴ to 50 × 10 ⁴ . When the weight average molecular weight is less than 0.2 × 10 ⁴ , the resin strength is low, which is not preferable as a binder. When the weight average molecular weight exceeds 100 × 10 ⁴ , the viscosity becomes too high and the productivity is deteriorated.

The glass transition point of the polymer (B) can be selected within a range that does not impair the film-forming properties and the like.
° C, preferably -15 to 45 ° C, more preferably 0 to 0 ° C.
It is about 30 ° C. If the glass transition point is lower than -40 ° C, the tackiness becomes too large, and if it exceeds 85 ° C, the film-forming properties deteriorate. The polymer (B) having such a glass transition point is
It can be prepared by appropriately combining the above various monomers. The monomer is usually a hard monomer [for example, a monomer that forms a homopolymer having a glass transition point of about 80 to 120 ° C (particularly 90 to 105 ° C) such as methyl (meth) acrylate, styrene, and the like]. A soft monomer [for example, a glass transition point of an alkyl acrylate (= C _2-10 ) ester or the like is −85 to −10 ° C. (particularly −85 to −2;
0 ° C.) to form a homopolymer. When the content of the monomer having a carboxyl group is less than 3 wt%, aggregation occurs when the emulsion is formed, and when it exceeds 30 wt%, the water resistance of the formed coating film may be deteriorated.

Preparation of Resin for Recording Display Layer The resin used for the recording display layer of the present invention comprises a urethane resin (A) and a polymer (B) of a polymerizable unsaturated monomer, and is a mixture. Alternatively, one of the urethane resin (A) and the polymer (B) may constitute a matrix, and the other component may be in a form of particles dispersed in the matrix. When giving priority to the flexibility of the coating film, the urethane resin (A) as a matrix preferably has a form in which the polymer (B) is dispersed in a particle form.

Urethane resin (A) in resin for recording display layer
Ratio (A / B) is within a range that does not impair other properties such as recording characteristics and water resistance, and A / B = 95/5 to 20/80.
(Wt%) [for example, 95/5 to 30/70 (wt
%)], And A / B = 90/10
40/60 (wt%), especially 85/15 to 50/50
(Wt%). If the ratio (A / B) of the urethane resin (A) exceeds 95/5 wt%, other properties such as recording characteristics and water resistance are impaired, and if it is less than 40/60 wt%, the coating film becomes hard. It is not preferable because flexibility is lost.

The average particle diameter of the dispersed particles (for example, polymer (B) of a polymerizable unsaturated monomer) is, for example, 0.00
It can be selected from a range of about 1 to 5 μm, preferably about 0.01 to 2 μm, and more preferably about 0.01 to 1 μm. If the average particle diameter is less than 0.001 μm, the viscosity is too high, which is not preferable.

A resin in which one component (for example, polymer (B)) is dispersed in the form of particles can be obtained by keeping one component (for example, polymer (B)) in the form of particles while maintaining the other component (for example, polymer (B)) in a particulate form. For example, it may be prepared by mixing with urethane resin (A)). As a preferable preparation method, for example, a method of mixing an emulsion of the urethane resin (A) and an emulsion of the polymer (B), a method of polymerizing in the presence of an emulsion containing polymer particles composed of the urethane resin (A), Examples of the method include emulsion polymerization of an unsaturated monomer. The emulsion polymerization may be a seed polymerization using the polymer particles containing the urethane resin (A) as a seed. Also,
The polymer particles containing the polymer (B) may be composed of not only the polymer (B) alone but also the urethane resin (A) and the polymer (B).

The emulsion polymerization can be carried out according to a conventional emulsion polymerization method. Emulsion polymerization includes, for example, (i) a method of emulsion-polymerizing a mixed solution of a urethane resin (A) and a polymerizable unsaturated monomer, (ii) in the presence of a polymer particle composed of the urethane resin (A), Emulsion polymerization of a polymerizable unsaturated monomer alone or a mixed solution of the polymerizable unsaturated monomer and the urethane resin (A) can be performed. The mixed solution of the urethane resin (A) and the polymerizable unsaturated monomer or the polymerizable unsaturated monomer may be used as a pre-emulsified emulsion. The mixed solution and the polymerizable unsaturated monomer may be charged all at once and may be polymerized, or may be partially charged and the remaining portion added for polymerization. The mixed solution and the polymerizable unsaturated monomer may be continuously added to the emulsion polymerization system by dropping or the like, or may be added intermittently. In the emulsion polymerization, a method combining these methods may be employed.

In the emulsion polymerization, a conventional method such as a multi-stage polymerization method can be employed. Multi-stage polymerization is performed continuously in the presence of, for example, polymer particles containing at least a urethane resin (A) or polymer particles formed by emulsion polymerization of a mixed solution of a urethane resin (A) and a polymerizable unsaturated monomer. Alternatively, it can be carried out intermittently by a method in which a polymerizable unsaturated monomer or a mixed solution of a urethane resin (A) and a polymerizable unsaturated monomer is added in multiple stages and emulsion polymerization is performed. In this method, the composition of the polymerizable unsaturated monomer or the mixed solution to be added may be different between the initial stage and the late stage of the emulsion polymerization step. For example, at a later stage than the initial stage, the proportion of the polymerizable unsaturated monomer in the mixed solution to be added is increased,
In the latter stage, a polymerizable unsaturated monomer may be used.

Emulsion polymerization can be carried out using a water-soluble polymerization initiator such as potassium persulfate, sodium persulfate, ammonium persulfate or the like, or hydrogen peroxide as a polymerization initiator. A redox-type polymerization initiator system may be constituted. Further, in order to adjust the molecular weight of the polymer (B), a chain transfer agent, for example, phenols such as catechol, alcohols, thiols, and mercaptans may be used. The polymerization temperature can be generally selected from the range of about 30 to 100 ° C., depending on the type of the polymerization initiator. If the polymerization temperature is lower than 30 ° C., the productivity is poor,
If the temperature exceeds 100 ° C., the amount of residual monomer is too large.

An emulsifier can be used in the preparation of an emulsion (for example, an emulsion of the urethane resin (A), etc.) and emulsion polymerization. Examples of the emulsifier include anionic surfactants (for example, sodium dodecylbenzenesulfonate, sodium alkyldiphenyletherdisulfonate, sodium alkylnaphthalenesulfonate, sodium lauryl sulfate, sodium polyoxyethylene alkyl ether sulfate, polyoxyethylene alkylphenyl ether Interfaces such as sodium sulfate and sodium dialkyl sulfosuccinate), nonionic surfactants (eg, polyoxyethylene lauryl ether, polyoxyethylene oleyl phenyl ether, polyoxyethylene nonyl phenyl ether, oxyethylene / oxypropylene block copolymer) Activators and protective colloids such as polyvinyl alcohol and water-soluble polymers. The amount of emulsifier used is
For example, 0.1 to 10% by weight, preferably 0.5% by weight based on the total amount of the urethane resin (A) and the polymerizable unsaturated monomer.
~ 8% by weight. More preferably, it is about 1 to 8% by weight. If the amount of the emulsifier is less than 0.1% by weight, emulsification becomes difficult. If the amount exceeds 10% by weight, the obtained resin properties are undesirably affected by the emulsifier.

Glass transition point (Tg) of resin for recording display layer
Is, for example, -20 ° C to 50 ° C, preferably -10 ° C to
It is about 40 ° C. The glass transition point (Tg) of the resin is-
If the temperature is lower than 20 ° C., the stickiness increases, which is not preferable. If the temperature is higher than 50 ° C., the film-forming property deteriorates. The minimum film formation temperature (MFT) of the aqueous emulsion is, for example, 0 to
The temperature is 40 ° C, preferably about 0 to 35 ° C. If the minimum film formation temperature (MFT) of the aqueous emulsion is less than 0 ° C., stickiness increases, which is not preferable, and if it exceeds 40 ° C., the film-forming property deteriorates. The pH of the emulsion may be adjusted, for example, in a neutral to weakly alkaline region of 5 or more (for example, 5 to 10), preferably about 6 to 9.

The resin particles in the resin (resin aqueous emulsion) obtained by emulsion polymerization may have a homogeneous structure or a hetero-phase structure (for example, a core-shell structure, a micro-domain structure, etc.). In the core-shell structure, the core layer is a urethane resin (A) or a polymer of a polymerizable unsaturated monomer (B), and the shell layer is a polymer of a polymerizable unsaturated monomer (B) or a urethane resin (A). ).

The average particle size of the resin particles is within a range that does not impair the dispersion stability and adhesion, for example, 0.01 to 5 μm.
m, preferably from 0.01 to 2 μm, more preferably from about 0.01 to 1 μm. If the average particle diameter of the resin particles is less than 0.01 μm, the viscosity is too high, which is not preferable. If it exceeds 5 μm, the stability of the particles is deteriorated.

In the present invention, the polymerizable unsaturated monomer (b) may be added to the resin for the recording display layer, if necessary.
Further, another polymerizable monomer (c) or another resin composed of the above cationic monomer as an optional component can be further blended. The weight average molecular weight of another resin is in the range of the molecular weight of the resin for the recording display layer. The weight ratio of another resin to the resin is 40 or less, preferably 30 or less, based on 100 of the resin.

Further, in order to improve display recording and other characteristics, for example, a fluorine resin,
Lubricant such as silicone resin, organic sulfonate compound, organic phosphate compound, organic carboxylate compound, stabilizer such as antioxidant, ultraviolet absorber, heat stabilizer, radical scavenger, quencher, electrification Additives such as inhibitors, plasticizers, thickeners and defoamers may be added.

Leuco Dyes The leuco dyes used in the present invention are typically represented by those used for pressure-sensitive recording paper and thermosensitive recording paper, but are not particularly limited. Specific examples include the following, but the present invention is not limited thereto. (1) Triarylmethane compound: 3,3-bis (p
-Dimethylaminophenyl) -6-dimethylaminophthalide (crystal violet lactone), 3,3-bis (p-dimethylaminophenyl) phthalide, 3- (p
-Dimethylaminophenyl) -3- (1,2-dimethylindol-3-yl) phthalide, 3- (p-dimethylaminophenyl) -3- (2-methylindole-3-
Yl) phthalide, 3- (p-dimethylaminophenyl)
-3- (2-Phenylindol-3-yl) phthalide, 3,3-bis (1,2-dimethylindol-3-
Yl) -5-dimethylaminophthalide, 3,3-bis (1,2-dimethylindol-3-yl) -6-dimethylaminophthalide, 3,3-bis (9-ethylcarbazol-3-yl) -5-dimethylaminophthalide,
3,3-bis (2-phenylindol-3-yl)-
5-dimethylaminophthalide, 3-p-dimethylaminophenyl-3- (1-methylpyrrol-2-yl) -6
-Dimethylaminophthalide and the like (2) Diphenylmethane compounds: 4,4'-bis (dimethylaminophenyl) benzhydrylbenzyl ether, N-chlorophenylleucouramine, N-2,
(3) Xanthene-based compounds: rhodamine B anilinolactam, rhodamine Bp-chloroanilinolactam,
-Diethylamino-7-dibenzylaminofluoran,
3-diethylamino-7-octylaminofluoran,
3-diethylamino-7-phenylfluoran, 3-diethylamino-7-chlorofluoran, 3-diethylamino-6-chloro-7-methylfluoran, 3-diethylamino-7- (3,4-dichloroanilino) fluoran , 3-diethylamino-7- (2-chloroanilino)
Fluoran, 3-diethylamino-6-methyl-7-anilinofluoran, 3- (N-ethyl) tolylamino-
6-methyl-7-anilinofluoran, 3-piperidino-6-methyl-7-anilinofluoran, 3- (N-ethyl) tolylamino-6-methyl-7-phenethylfluoran, 3-diethylamino-7 -(4-nitroanilino) fluoran, 3-dibutylamino-6-methyl-7
-Anilinofluoran, 3- (N-methyl) propylamino-6-methyl-7-anilinofluoran, 3- (N
-Ethyl) isoamylamino-6-methyl-7-anilinofluoran, 3- (N-methyl) cyclohexylamino-6-methyl-7-anilinofluoran, 3- (N-
Ethyl) tetrahydrofurylamino-6-methyl-7-
(4) Thiazine compounds: benzoyl leucomethylene blue, p-nitrobenzoyl leucomethylene blue, etc. (5) Spiro compounds: 3-methylspirodinaphthopyran, 3-ethylspirodinaphthopyran, 3,3 ′ -Dichlorospirodinaphthopyran, 3-benzylspirodinaphthopyran, 3-methylnaphtho- (3-methoxybenzo)
Spiropyran, 3-propyl spirobenzopyran and the like. As the above usually colorless to light-colored leuco dyes, one kind or a mixture of two or more kinds may be used.

Examples of the reversible developer used in the present invention include, but are not limited to, those represented by the following general formula (1), and are not limited thereto. The compound is not particularly limited as long as it is a compound that causes the following. From the viewpoint of image contrast, repetition durability and the like, a reversible color developer composed of a phenolic compound proposed in JP-A-6-210954 is used. The electron accepting compound represented by (1) is preferably used.

[0051]

Embedded image

In the formula, n represents 1, 2 or 3. m is 0,
Represents 1 or 2. Q represents an aliphatic hydrocarbon group, an alkoxy group, or a halogen atom. The ring represented by A is an aromatic ring. X is a divalent group bonded to the aromatic ring represented by A via a nitrogen atom, a divalent group containing 2 to 10 hetero atoms,
An aromatic ring represented by A containing a nitrogen atom and having 1 to 12 carbon atoms
Or a divalent group containing an unsaturated bond or an aromatic ring. R represents an aliphatic hydrocarbon group. The total number of atoms excluding the hydrogen atoms and the atoms constituting the aromatic ring among the atoms contained in X and R is 8 to 4
0.

Specific examples of the substituent represented by Q include methyl, ethyl, propyl, isopropyl, n-
Butyl group, t-butyl group, t-pentyl group, 2-ethylhexyl group, cyclohexyl group, aliphatic hydrocarbon group such as allyl group, methoxy group, ethoxy group, n-propyloxy group, i-propyloxy group, n -Butyloxy group, n
-An alkoxy group such as octyloxy group and the like, and a halogen atom such as fluorine, chlorine, bromine and iodine.

Examples of the divalent group in which X is bonded to the aromatic ring represented by A via a nitrogen atom include -NHCO-,-
NH-, -NHCONH-, -NHCONHNH-,-
N = CH -, - N = N -, - NHSO 2 -, - NHCO
_{(P-C 6 H 4)} NHCO -, - NHCO (p-C 6 H 4)
NHCONH -, - NHCO (p- C 6 H 4) NHCOC
ONH -, - NHCO (p- C 6 H 4) CONH -, - N
_{HCO (p-C 6 H 4} ) CONHNHCO -, - NHCO
_{(P-C 6 H 4)} OCONH -, - NHCO (p-C
_{6 H 4) NHCOO -, -} NHCOCH 2 (m-C 6 H 4)
_{NHCO -, - NHCOCH 2 (p} -C 6 H 4) NHCO
_{-, - NHCOCH 2 (p-} C 6 H 4) NHCONH-,
_{-NHCOCH 2 (p-C 6 H} 4) NHCOCONH-,
_{-NHCOCH 2 (p-C 6 H} 4) CONH -, - NHC
_{OCH 2 (p-C 6 H} 4) CONHNHCO -, - NHC
_{OCH 2 (p-C 6 H} 4) CONHNHCONH -, - N
HCOCH ₂ (p-C ₆ H ₄ ) CONNHNHCOO-,-
_{NHCOCH 2 (p-C 6 H} 4) OCONH -, - NHC
_{OCH 2 (p-C 6 H} 4) NHCOO -, - NHCOCH 2
_{CH 2 (p-C 6 H} 4) NHCO -, - NHOCCH 2 CH
_{2 (p-C 6 H 4} ) NHCONH -, - NHCOCH 2 CH
_{2 (m-C 6 H 4} ) NHCOO -, - NHCOCH 2 CH 2
_{(P-C 6 H 4)} NHCOCONH -, - NHCOCH 2
_{CH 2 (p-C 6 H} 4) CONH -, - NHCOCH 2 CH
_{2 (p-C 6 H 4} ) CONHNHCO -, - NHCOCH 2
_{CH 2 (p-C 6 H} 4) CONHNHCONH- the like. When a hydrogen atom is bonded to the nitrogen atom, the hydrogen atom may be substituted with an aliphatic hydrocarbon group such as a methyl group or a cyclohexyl group. Among these, a urea bond is more preferable in terms of decoloring property and image density. Interestingly, when X is -CONH-, -COO-, -S-
Either the decoloring property or the image density becomes unsatisfactory.

X is a divalent group containing 2 to 10 heteroatoms.
Examples of groups include -SO_TwoNH-, -SS-, -CO
NHNH-, -CONHNHCO-, -CONHCH_Two
CO-, -CONHNHCOO-, -CONHCH_TwoC
OO-, -CONHNHCONH-, -CONHCH_Two
CONH-, -CONHNHCONHNH-, -CON
HCH_TwoCONHNH-, -CH_TwoNHCONH-, -C
H_TwoCH_TwoNHCONH-, -CH_TwoCH_TwoCH_TwoNHCO
NH-, -CH_TwoCH_TwoCH_TwoNHCONH-, -SCH_Two
CONH-, -SCH_TwoCH_TwoCONH-, -S (C
H_Two)_FiveCONH-, -S (CH_Two)_TenCONH-, -S
(P-C₆H_Four) CONH-, -SCH_TwoNHCO-,-
SCH_TwoCH_TwoNHCO-, -S (CH_Two)₆NHCO-,
-S (p-C₆H_Four) NHCO-, -SCH_TwoNHCON
H-, -SCH_TwoCH_TwoNHCONH-, -S (CH_Two)₆
NHCONH-, -S (p-C₆H_Four) NHCONH-,
-S (CH_Two)_TenNHCONH-, -SCH_TwoCH_TwoNH
COO-, -S (CH_Two)₆NHCOO-, -S (p-C
₆H_Four) NHCOO-, -S (CH_Two)₆OCONH-,-
S (p-C₆H_Four) OCONH-, -S (CH_Two)₁₁OC
ONH-, -SCH_TwoCH_TwoCONH-, -S (CH_Two)_Five
CONH-, -SCH_TwoCH_TwoNHCO (p-C₆H_Four)
-, -SCH_TwoCONHNHCO-, -SCH_TwoCH_TwoC
ONHNHCO-, -S (CH_Two)₆CONHNHCO
-, -S (CH_Two)₆CONNHNHCO (p-C₆H_Four)
-, -S (CH_Two)_TenCONHNHCO-, -S (p-
C₆H_Four) CONHNHCO-, -SCH_Two(P-C
₆H_Four) CONHNHCO-, -SCH_TwoCH_TwoNHCOC
ONH-, -SCH_TwoCH_TwoCH_TwoNHCOCONH-,
-S (CH_Two)₁₁NHCOCONH-, -S (p-C₆H
_Four) NHCOCONH-, -SCH_TwoCONHCONH
-, -SCH_TwoCH_TwoCONHCONH-, -S (p-C
₆H_Four) CONHCONH-, -SCH_TwoCH_TwoNHCON
HCO-, -S (p-C₆H_Four) NHCONHCO-,-
SCH_TwoCH_TwoCONHNHCONH-, -S (CH_Two)
_TenCONHNHCONH-, -SCH_TwoCH_TwoNHNHC
ONH-, -S (p-C₆H_Four) NHNHCONH-,-
SCH_TwoCH_TwoNHCONHNH-, -S (p-C₆H_Four)
NHCONHNH-, -SCH_TwoCONHCONHNH
-, -SCH_TwoCH_TwoCONHCONHNH-, -S (C
H_Two)_TenCONHCONHNH-, -S (p-C₆H_Four)
CONHNHCONH-, -S (p-C₆H_Four) CONH
CONHNH-, -SCH_TwoCONHCONHNHCO
-, -SCH_TwoCH_TwoCONHCONHNHCO-, -S
(CH_Two)_TenCONHCONHNHCO-, -S (p-
C₆H_Four) CONHNHCONHCO-, -S (p-C₆
H_Four) CONHCONHNHCO-, -SCH_TwoCONH
(CH_Two)_TenNHCO-, -SCH_TwoCH_TwoCONH (C
H_Two)_{1 0}NHCO-, -S (p-C₆H_Four) CONH (C
H_Two)_TenNHCO-, -S (CH _Two)_TenCONH (C
H_Two)_TenNHCO-, -SCH_TwoCONH (CH_Two)_TenN
HCONH-, -SCH_TwoCH_TwoCONH (CH_Two)_TenN
HCONH-, -S (CH_Two)_TenCONHCONH (C
H_Two)_TenNHCO-, -S (p-C₆H_Four) CONH (C
H_Two)_TenNHCO-, -SCH_TwoCH_TwoNHCONH (C
H_Two)_TenNHCO-, -SCH_TwoCH_TwoNHCOCH_TwoCO
NH-, -S (p-C₆H_Four) NHCONH (CH_Two) _Ten
NHCO-, -S (p-C₆H_Four) NHCOCH_TwoCON
H- and the like. Specific examples of heteroatoms include acids
Element atom, nitrogen atom, sulfur atom, phosphorus atom, boron atom, silicon
Element, selenium, fluorine, chlorine, bromine,
Examples thereof include an iodine atom and a tin atom.

X represents an unsaturated bond or an aromatic ring-containing 2
Examples of the valent group include -CH = CH-, -CH = N-,
—SO ₂ —, a phenylene group, a group containing a carbon-carbon triple bond and the like, a group obtained by combining them, and further, on one or both sides thereof, —NHCO
-, -NH-, -NHCONH-, -NHCSNH-,
-N = CH -, - N = N -, - NHSO 2 -, - SO 2 N
Examples thereof include a group obtained by combining one or more of linking groups such as H- and -SS-. In this case, as a connecting group, besides -CONH-, -O-, -S-, -COO-,-
₂ such as OCO-, -OCOO-, -CO-, -SO2-, etc.
Valent groups are also included.

Examples of the divalent group in which X contains a nitrogen atom and is bonded to the aromatic ring represented by A by a hydrocarbon group having 1 to 12 carbon atoms include -CH ₂ CONH- and -CH ₂ CH ₂ C
_{ONH -, - CH 2 NHCO -} , - CH 2 CH 2 NHCO
_{-, - CH 2 CH 2 CH} 2 NHCO -, - CH 2 CH 2 NH
_{COO -, - (CH 2)} 6 NHCOO -, - (p-C
_{6 H 4) NHCOO -, -} CH 2 CH 2 OCONH -, -
_{(CH 2) 11 OCONH -,} - (p-C 6 H 4) OCON
_{H -, - CH 2 CH 2} CONHCO -, - (CH 2) 5 CO
_{NHCO -, - CH 2 CH 2} CONHCO (p-C 6 H 4)
_{-, - CH 2 CONHNHCO -,} - CH 2 CH 2 CON
_{HNHCO -, - (CH 2)} 5 CONHNHCO -, -
_{(CH 2) 5 CONHNHCO (p} -C 6 H 4) -, - (C
_{H 2) 10 CONHNHCO -, -} (p-C 6 H 4) CON
_{HNHCO -, - CH 2 (p} -C 6 H 4) CONHNHC
_{O -, - CH 2 CH 2} NHCOCONH -, - CH 2 CH 2
_{CH 2 NHCOCONH -, - (CH} 2) 10 NHCOCO
NH -, - (p-C 6 H 4) NHCOCONH -, - CH
_{2 CONHCONH -, - CH 2 CH} 2 CONHCONH
_{-, - (p-C 6} H 4) CONHCONH -, - CH 2 C
_{H 2 NHCONHCO -, - (p} -C 6 H 4) NHCON
_{HCO -, - CH 2 CH 2} NHCONHNH -, - (p-
_{C 6 H 4) NHCONHNH -,} - CH 2 CH 2 NHNHC
ONH -, - (p-C 6 H 4) NHNHCONH -, - C
_{H 2 CONHNHCONH -, - CH 2} CH 2 CONHN
_{HCONH -, - (CH 2)} 10 CONHNHCONH
_{-, - (p-C 6} H 4) NHNHCO -, - CH 2 CON
_{HCH 2 NHCO -, - CH 2} CH 2 CONHCH 2 NHC
_{O -, - (CH 2)} 10 CONHCH 2 NHCO -, - (p
—C ₆ H ₄ ) CONHCH ₂ NHCO—, —CH ₂ CONH
_{CH 2 NHCONH -, - CH 2} CH 2 CONHCH 2 NH
_{CONH -, - (CH 2)} 10 CONHCH 2 NHCONH
_{-, - (p-C 6} H 4) CONHCH 2 NHCONH-,
_{-CH 2 CH 2 NHCONHCH 2 NHCO -} , - (p-
_{C 6 H 4) NHCONHCH 2 NHCO} -, - CH 2 CH 2
_{NHCOCH 2 CONH -, - (p} -C 6 H 4) NHCO
CH ₂ CONH— and the like.

As the aliphatic hydrocarbon group represented by R,
Hexyl, octyl, nonyl, cyclohexyl, decyl, undecyl, dodecyl, cyclododecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl, heptadecyl, 16-methylheptadecyl, octadecyl, 9-octadecenyl group, nonadecyl group, eicosyl group, heneicosyl group,
Examples include a docosyl group, a tricosyl group, a tetracosyl group, a 2-norbornyl group, a 7,7-dimethylnorbornyl group, a 1-adamantyl group, a cholesteryl group, and a 5-phenylpentyl group. These may be branched, may be polycyclic, and may contain an unsaturated bond. However, among the atoms contained in X and R, the total number of atoms excluding hydrogen atoms and atoms constituting the aromatic ring is 8 to 4
0, especially 14 to 30 is necessary for the decoloring property.

Next, specific examples of the reversible developer preferably used in the present invention will be described, but the present invention is not limited thereto.
4'-hydroxyheptaneanilide, 4'-hydroxy-3-methyloctaneanilide, 4'-hydroxynonadecananilide, 3'-hydroxynonadecananilide, 4'-hydroxy-10-octadeceneanilide,
15-cyclohexyl-4'-hydroxypentadecaneanilide, 4'-hydroxy-5-tetradecenanilide, 3'-cyclohexyl-4'-hydroxyheptadecaneanilide, 3'-allyl-4'-hydroxypentadecaneanilide, 3'- Chloro-4'-hydroxyoctadecaneanilide, 3'-hydroxydodecananilide, 2 ', 4'-dihydroxyheptadecaneanilide,
4'-hydroxy-4-hexylbenzanilide, 4 '
-Hydroxy-4-octadecylbenzanilide, 4 '
-Hydroxy-4-pentadecylaminocarbonylbenzanilide, 4'-hydroxy-4-hexylcarbonylaminobenzanilide, 4'-hydroxy-4- (heptylthio) benzanilide, 4'-hydroxy-4-
Octadecyloxybenzanilide, 4'-hydroxy-4-dodecylsulfonylbenzanilide, 4'-hydroxy-4-nonylsulfonyloxybenzanilide,
4'-hydroxy-4-dodecyloxysulfonylbenzanilide, 4'-hydroxy-4-pentadecylaminosulfonylbenzanilide, 4'-hydroxy-4-
(N-heptadecylideneamino) benzanilide, 4 '
-Hydroxy-3,4-dioctyloxybenzanilide, 4'-hydroxy-3-octyl-4- (octylthio) benzanilide, 4'-hydroxy-3- (heptadecylthio) -5-pentadecyloxybenzanilide, 4'- Hydroxy-3-heptadecylcarbonylamino-5-dodecylbenzanilide, 4'-hydroxy-3-octadecylaminocarbonyl-5-tetradecylaminocarbonylbenzanilide, 4'-hydroxy-3-octadecylsulfonylamino-5-octadecyloxy Benzanilide, 4'-hydroxy-3-heptadecyloxysulfonyl-5-tetradecyloxysulfonyl benzanilide, 4'-hydroxy-3,5-
Bis (N-docosylideneamino) benzanilide, 4 '
-Hydroxy-4-octadecylcarbonylaminobenzanilide, 4'-hydroxy-3-octadecylcarbonylamino-5-octadecyloxybenzanilide, 3'-allyl-4'-hydroxy-4-pentadecylbenzanilide, 4'-hydroxy -3'-methyl-
4-nonyloxybenzanilide, 4'-hydroxy-
3'-propyl-4-nonadecylcarbonyloxybenzanilide, 3'-butyl-4'-hydroxy-4-octadecyloxycarbonylbenzanilide, 3'-hydroxy-4-pentadecylcarbonyloxybenzanilide, 3'-hydroxy -4-nonadecylsulfonylbenzanilide, 3 ', 4', 5'-trihydroxy-
4-tetracosylaminosulfonylbenzanilide,
3 ', 5'-dihydroxy-4-pentacosylaminocarbonylbenzanilide, 3'-hydroxy-4- (N
-Dodecylideneamino) benzanilide,

N- [4- (3-hydroxyphenylaminocarbonyl) benzylidene] pentadecylamine, N
-Cyclohexyl-4-hydroxybenzhydrazide,
N-cyclohexylmethyl-4-hydroxybenzhydrazide, N-cyclohexyl-4-hydroxybenzamide, N-cyclohexylmethyl-4-hydroxybenzamide, N-methyl-N-octadecyl-4-hydroxybenzamide, N- (3-methylhexyl ) -4-
Hydroxybenzamide, N-octadecyl-4-hydroxybenzhydrazide, N- (8-octadecenyl)
-4-hydroxybenzamide, 4-hydroxy-4 '
-Dodecylbenzanilide, N-methyl-4-hydroxy-4'-octadecylbenzanilide, 4-hydroxy-4'-octadecyloxybenzanilide, 4-hydroxy-4 '-(octadecylthio) benzanilide, 4-hydroxy-4 '-Hexadecylcarbonylbenzanilide, 4-hydroxy-4'-heptadecyloxycarbonyloxybenzanilide, 4-hydroxy-4'-dodecyloxycarbonylbenzanilide,
-Hydroxy-4'-heptadecylcarbonyloxybenzanilide, 4-hydroxy-4'-cyclohexylaminobenzanilide, 4-hydroxy-4'-octadecylaminobenzanilide, 4-hydroxy-4'-
Heptadecylcarbonylaminobenzanilide, 4-hydroxy-4'-octadecylaminocarbonylbenzanilide, 4-hydroxy-4'-dodecylsulfonylbenzanilide, 4-hydroxy-4'-octadecyloxysulfonylbenzanilide, 4-hydroxy-4 '-Dodecylsulfonyloxybenzanilide,

N-4-hydroxybenzoyl-N'-octadecylidene-1,4-phenylenediamine, N-4
-(4-hydroxyphenylcarbonylamino) benzylidenedecylamine, 4-hydroxy-4'-tetradecyloxycarbonylaminobenzanilide, 4-hydroxy-4'-octadecylureylenebenzanilide, 3-hydroxy-4'-dodecyloxy Benzanilide, N-methyl-4-hydroxy-3'-octadecyloxybenzanilide, 3-hydroxy-4'-tetradecylbenzanilide, N-methyl-3-hydroxy-4'-octadecylbenzanilide, N-dodecyl-
4-hydroxy-3-methylbenzamide, 3-methoxy-4-hydroxy-4'-octadecyloxybenzanilide, 3-chloro-4-hydroxy-4'-octadecylbenzanilide, N-octadecyl-4-hydroxy-2, 5-dimethylbenzamide, 4-hydroxy-4'-octadecyloxy-3'-chlorobenzanilide, 4-hydroxy-3 ', 4'-didecyloxybenzanilide, 4-hydroxy-3'-octadecylamino-4' -Octadecyloxybenzanilide, 4-
Hydroxy-2'-chloro-3 ', 5'-didecyloxybenzanilide, 4-hydroxy-3', 4'-dioctadecyloxybenzanilide, 4-hydroxy-
4'-octyl-3'-methylbenzanilide, 3-hydroxy-4-methyl-4'-tetradecylbenzanilide, N-methyl-4-hydroxy-3'-octadecylbenzanilide,

4- (N-octadecylsulfonylamino) phenol, 4- (N-methyl-N-octadecylsulfonylamino) phenol, 4- (N-3-methylhexylsulfonylamino) phenol, 4'-hydroxy-4- Cyclohexylbenzenesulfonanilide,
4'-hydroxy-4-octadecyloxybenzenesulfonanilide, 4'-hydroxy-4- (dodecylthio) benzenesulfonanilide, 4'-hydroxy-4
-Hexylcarbonylbenzenesulfonanilide, 4 '
-Hydroxy-4- (8-heptadecenyl) carbonylbenzenesulfonanilide, 4'-hydroxy-4-octyloxycarbonyloxybenzenesulfonanilide, 4'-hydroxy-4-dodecylcarbonyloxybenzenesulfonanilide, 4'-hydroxy-4 -Octadecylaminobenzenesulfonanilide, 4'-hydroxy-4-heptadecylcarbonylaminobenzenesulfonanilide, 4'-hydroxy-4-dodecylaminocarbonylbenzenesulfonanilide, 4'-hydroxy-4-dodecylsulfonylbenzenesulfonanilide, '-Hydroxy-4-octadecyloxysulfonylbenzenesulfonanilide, 4'-hydroxy-
4-dodecylsulfonyloxybenzenesulfonanilide, N-dodecylidene-4- (4-hydroxyphenyl) aminosulfonylaniline, N-4- (4-hydroxyphenylaminosulfonyl) benzylideneoctadecylamine, 4'-hydroxy-4-octyloxy Carbonylaminobenzenesulfonanilide, 4'-hydroxy-4-octadecyloxycarbonylaminobenzenesulfonanilide, 4'-hydroxy-4-octadecylureylenebenzenesulfonanilide, N-methyl-4'-hydroxy-3-octadecyloxybenzenesulfone Anilide, 3'-hydroxy-4-dodecylbenzenesulfonanilide, 3-methyl-4- (N-dodecylsulfonamino) phenol, 3'-methoxy-
4'-hydroxy-4-octadecyloxybenzenesulfonanilide, 3'-chloro-4'-hydroxy-4
-Octadecylbenzenesulfonanilide, 4'-hydroxy-2,5-dimethyl-4-octadecylbenzenesulfonanilide, 3-methyl-4- (N-octadecylsulfonamino) phenol, 4'-hydroxy-
3,4-dioctadecyloxybenzenesulfoneanilide,

1- (4-hydroxyphenyldithio) octadecane, 1- (4-hydroxyphenyldithio)-
9-octadecene, 1- (2-fluoro-4-hydroxyphenyldithio) octadecane, 1- (2-ethoxy-4-hydroxyphenyldithio) octadecane, 1-
(3-chloro-4-hydroxyphenyldithio) octadecane, 4'-hydroxy-4-tetradecyldiphenylsulfide, 4'-hydroxy-4-octadecyldiphenylsulfide, 4'-hydroxy-4-octadecylcarbonylaminodiphenylsulfide, '-Hydroxy-4-octadecyloxydiphenyl sulfide, 4'-hydroxy-4-octadecyloxysulfonyldiphenyl sulfide, 4'-hydroxy-4-octadecylsulfonylaminodiphenyl sulfide,
4'-hydroxy-3,4-didecyloxydiphenyl sulfide, 4'-hydroxy-3,4-dioctadecyloxydiphenyl sulfide, 4- (15-cyclohexylpentadecyl) -4'-hydroxydiphenyl sulfide, 4'- Hydroxy-4- (5-tetradecenyl) diphenyl sulfide, 3'-chloro-4'-hydroxy-4-octadecyl diphenyl sulfide, 3 '
-Hydroxy-4-dodecyldiphenyl sulfide,
3'-hydroxy-4-octadecyldiphenyl sulfide, 3'-hydroxy-4-dodecyloxycarbonyldiphenyl sulfide,

N- (4-hydroxyphenyl) -N'-
Hexylurea, N- (4-hydroxyphenyl) -N '
-Dodecyl urea, N- (4-hydroxyphenyl)-
N'-hexadecyl urea, N- (4-hydroxyphenyl) -N'-octadecyl urea, N- (4-hydroxyphenyl) -N'-eicosyl urea, N- (4-hydroxyphenyl) -N'-cyclododecyl Urea, N- (4
-Hydroxyphenyl) -N'-docosylurea, N-
(4-hydroxyphenyl) -N'-cholesteryl urea, N- (4-hydroxyphenyl) -N '-(2-heptyloctyl) urea, N- (4-hydroxyphenyl) -N'-(9-octadecenyl) Urea, N- (3-
Allyl-4-hydroxyphenyl) -N'-octadecyl urea, N- (2-hydroxyphenyl) -N'-octyl urea, N- (3-hydroxyphenyl) -N'-octadecyl urea, N- (3,4 -Dihydroxyphenyl) -N'-octadecyl urea, N- (3,4,5-trihydroxyphenyl) -N'-tricosyl urea, N-
(4-hydroxyphenyl) -N '-(4-tetradecylphenyl) urea, N- (4-hydroxyphenyl)-
N'-hexadecylthiourea, N- (4-hydroxyphenyl) -N'-octadecylthiourea, 4-undecanoylamino-1- (4-hydroxyphenylaminocarbonyl) benzene, 4-octadecanoylamino-1
-(4-hydroxyphenylaminocarbonyl) benzene, 4- (octadecylaminocarbonyl) amino-1
-(4-hydroxyphenylaminocarbonyl) benzene, 4-octadecylamino-1- (4-hydroxyphenylamino) carbonylmethylbenzene,

N-octadecyl-N'-p- (4-hydroxyphenylcarbamoyl) phenyl oxamide, 4
-(Octadecylaminocarbonyl) amino-1- (4
-Hydroxyphenylcarbamoyl) methylbenzene,
4- (octadecylamino) carbonyl-1- (4-hydroxyphenylcarbamoyl) methylbenzene, N-
Octadecanoyl-N'-p- (p-hydroxyphenylcarbamoylmethyl) benzoylhydrazine, N-dodecanoyl-N'-p- [2- (p-hydroxyphenylcarbamoyl) ethyl] benzoylhydrazine, N-
(4-hydroxyphenylmethyl) -N'-n-tetradecylurea, N- (4-hydroxyphenylmethyl)-
N'-n-octadecyl urea, N- [2- (4-hydroxyphenyl) ethyl] -N'-n-tetradecyl urea, N- [2- (4-hydroxyphenyl) ethyl]-
N'-n-octadecyl urea, N- [3- (4-hydroxyphenyl) propyl] -N'-n-dodecyl urea,
N- [3- (4-hydroxyphenyl) propyl]-
N'-n-octadecyl urea, N- [6- (4-hydroxyphenyl) hexyl] -N'-n-dodecyl urea,
N- [2- (3-hydroxyphenyl) ethyl] -N '
-N-octadecyl urea, N- [2- (3,4-dihydroxyphenyl) ethyl] -N'-n-octadecyl urea,

Nn-octadecyl- (4-hydroxyphenyl) acetamide, Nn-dodecyl-3- (4
-Hydroxyphenyl) propanamide, Nn-octadecyl-3- (4-hydroxyphenyl) propanamide, N- (4-hydroxyphenylmethyl) octadecanamide, N- [2- (4-hydroxyphenyl) ethyl] octadecane Amide, N- [3- (4-hydroxyphenyl) propyl] octadecanamide, N- [3
-(3-hydroxyphenyl) propyl] octadecanamide, N- [3- (3,4-dihydroxyphenyl)
Propyl] octadecaneamide, N- (4-hydroxybenzoyl) -N'-n-octanoylhydrazine, N
-(4-hydroxybenzoyl) -N'-n-tetradecanoylhydrazine, N- (4-hydroxybenzoyl) -N'-n-octadecanoylhydrazine, N-
(2,4-dihydroxybenzoyl) -N'-n-octanoylhydrazine, N- (2,4-dihydroxybenzoyl) -N'-n-octadecanoylhydrazine, N
-(4-hydroxybenzoyl) -N'-n-tetradecylaminocarbonylhydrazine, N- (4-hydroxybenzoyl) -N'-n-octadecylaminocarbonylhydrazine, N- (2,4-dihydroxybenzoyl) -N '-N-tetradecylaminocarbonylhydrazine, N- (2,4-dihydroxybenzoyl) -N'
-N-octadecylaminocarbonylhydrazine, N-
(4-hydroxybenzoyl) -N'-n-octyloxycarbonylhydrazine, N- (4-hydroxybenzoyl) -N'-n-dodecyloxycarbonylhydrazine, N- (2,4-dihydroxybenzoyl) -N '
-N-tetradecyloxycarbonylhydrazine, N-
(2,4-dihydroxybenzoyl) -N'-n-octadecyloxycarbonylhydrazine, N- (4-hydroxybenzoyl) -N'-n-tetradecylhydrazinocarbonylhydrazine, N- (4-hydroxybenzoyl) -N '-N-octadecylhydrazinocarbonylhydrazine, N- (2,4-dihydroxybenzoyl)
-N'-n-tetradecylhydrazinocarbonylhydrazine, N- (2,4-dihydroxybenzoyl) -N '
-N-octadecylhydrazinocarbonylhydrazine,

N- (4-hydroxybenzoyl) -N '
-N-octanoylmethylenediamine, N- (4-hydroxybenzoyl) -N'-n-tetradecanoylmethylenediamine, N- (4-hydroxybenzoyl)-
N'-n-octadecanoyl methylenediamine, N-
(2,4-dihydroxybenzoyl) -N'-n-tetradecanoylmethylenediamine, N- (2,4-dihydroxybenzoyl) -N'-n-octadecanoylmethylenediamine, N- (4-hydroxybenzoyl) −
N'-n-octylaminocarbonylmethylenediamine, N- (4-hydroxybenzoyl) -N'-n-dodecylaminocarbonylmethylenediamine, N- (4-
(Hydroxybenzoyl) -N'-n-tetradecylaminocarbonylmethylenediamine, N- (4-hydroxybenzoyl) -N'-n-octadecylaminocarbonylmethylenediamine, N- (2,4-dihydroxybenzoyl) -N'- n-octadecylaminocarbonylmethylenediamine, N- (4-hydroxybenzoyl)-
N'-n-tetradecyloxycarbonylmethylenediamine, N- (4-hydroxybenzoyl) -N'-n-
Octadecyloxycarbonylmethylenediamine, N-
(2,4-dihydroxybenzoyl) -N'-n-tetradecyloxycarbonylmethylenediamine, N-
(2,4-dihydroxybenzoyl) -N'-n-octadecyloxycarbonylmethylenediamine, N- (4
-Hydroxybenzoyl) -N'-n-octylhydrazinocarbonylmethylenediamine, N- (4-hydroxybenzoyl) -N'-n-dodecylhydrazinocarbonylmethylenediamine, N- (2,4-dihydroxybenzoyl) -N '-N-tetradecylhydrazinocarbonylmethylenediamine, N- (2,4-dihydroxybenzoyl) -N'-n-octadecylhydrazinocarbonylmethylenediamine, Nn-octadecyl-2-
(P-hydroxyphenylthio) acetamide, Nn
-Octadecyl-3- (p-hydroxyphenylthio)
Propanamide, Nn-decyl-11- (p-hydroxyphenylthio) undecaneamide, N- (pn-
Octylphenyl) -6- (p-hydroxyphenylthio) hexanamide, Nn-octadecyl-p- (p
-Hydroxyphenylthio) benzamide, N- [2-
(P-hydroxyphenylthio) ethyl] -n-octadecanamide, N- [p- (p-hydroxyphenylthio) phenyl] -n-octadecanamide,

N- (p-hydroxyphenylthio) methyl-N'-n-octadecyl urea, N- [2- (p-hydroxyphenylthio) ethyl] -N'-n-tetradecyl urea, N- [2- (P-hydroxyphenylthio)
Ethyl] -N'-n-octadecylurea, N- [2-
(3,4-dihydroxyphenylthio) ethyl] -N '
-N-octadecyl urea, N- [p- (p-hydroxyphenylthio) phenyl] -N'-n-octadecyl urea, N- [10- (p-hydroxyphenylthio) decyl] -N'-n-decyl Urea, N- [2- (p-hydroxyphenylthio) ethyl] -n-octadecylcarbamate, N- [p- (p-hydroxyphenylthio) phenyl] carbamate-n-dodecyl, Nn-octadecylcarbamine Acid- [2- (p-hydroxyphenylthio) ethyl], N- [3- (p-hydroxyphenylthio) propionyl] -Nn-octadecanoylamine, N- [2- (p-hydroxyphenylthio) ) Aceto] -N'-n-octadecanohydrazide, N- [3-
(P-Hydroxyphenylthio) propiono] -N'-
n-octadecanohydrazide, N- [3- (3,4-dihydroxyphenylthio) propiono] -N'-n-octadecanohydrazide, N- [6- (p-hydroxyphenylthio) hexano] -N '-N-tetradecanohydrazide, N- [6- (p-hydroxyphenylthio) hexano] -N'-n-octadecanohydrazide, N-
[6- (p-hydroxyphenylthio) hexano] -N
'-(Pn-octylbenzo) hydrazide, N- [1
1- (p-hydroxyphenylthio) undecano] -N
'-N-decanohydrazide, N- [11- (p-hydroxyphenylthio) undecano] -N'-n-tetradecanohydrazide, N- [11- (p-hydroxyphenylthio) undecano] -N' -N-octadecanohydrazide, N- [11- (p-hydroxyphenylthio) undecano] -N '-(6-phenyl) hexanohydrazide, N- [11- (3,4,5-trihydroxyphenyl) Thio) undecano] -N'-n-octadecanohydrazide, N- [p- (p-hydroxyphenylthio) benzo] -N'-n-octadecanohydrazide, N- [p-
(P-Hydroxyphenylthiomethyl) benzo] -N '
-N-octadecanohydrazide,

N- [3- (p-hydroxyphenylthio) propyl] -N'-n-octadecyl oxamide;
N- [3- (3,4-dihydroxyphenylthio) propyl] -N'-n-octadecyloxamide, N- [1
1- (p-hydroxyphenylthio) undecyl] -N
'-N-decyloxamide, N- [p- (p-hydroxyphenylthio) phenyl] -N'-n-octadecyloxamide, N- [2- (p-hydroxyphenylthio) acetyl] -N'-n- Octadecyl urea, N-
[3- (p-hydroxyphenylthio) propionyl]
-N'-n-octadecyl urea, N- [2- (p-hydroxyphenylthio) ethyl] -N'-n-octadecanoyl urea, N- [p- (p-hydroxyphenylthio) phenyl] -N '-N-octadecanoyl urea, 3
-[3- (p-hydroxyphenylthio) propionyl] -n-octadecylcarbamate, 4- [2- (p
-Hydroxyphenylthio) ethyl] -1-n-octadecylsemicarbazide, 1- [2- (p-hydroxyphenylthio) ethyl] -4-n-octadecylsemicarbazide, 1- [p- (p-hydroxyphenylthio) phenyl ] -4-n-tetradecylsemicarbazide, 1-
[3- (p-hydroxyphenylthio) propionyl]
-4-n-octadecylsemicarbazide, 1- [p-
(P-Hydroxyphenylthio) benzoyl] -4-n
-Octadecyl semicarbazide, 4- [2- (p-hydroxyphenylthio) ethyl] -1-n-tetradecanoyl semicarbazide, 4- [p- (p-hydroxyphenylthio) phenyl] -1-n-octadecanoyl Semicarbazide,

1- [2- (p-hydroxyphenylthio) acetamido] -1-n-octadecanoylaminomethane, 1- [11- (p-hydroxyphenylthio)
Undecaneamide] -N'-n-decanoylaminomethane, 1- [p- (p-hydroxyphenylthio) benzamide] -1-n-octadecanoylaminomethane, 1
-[3- (p-hydroxyphenylthio) propanamide] -1- (N'-n-octadecylureido) methane, 1- [11- (p-hydroxyphenylthio) undecaneamide] -N '-(N' -N-decylureido)
Methane, 1- {N ′-[2- (p-hydroxyphenylthio) ethyl] ureide} -1-n-octadecanoylaminomethane, N- [2- (p-hydroxyphenylthio) ethyl] -N ′ -N-octadecylmalonamide,
N- [2- (p-hydroxyphenyl) ethyl] -n-octadecylcarbamate, Nn-octadecylcarbamate- [2- (p-hydroxyphenyl) ethyl], N- [3- (p-hydroxyphenyl) ) Propionyl] -Nn-octadecanoylamine, N- [6-
(P-Hydroxyphenyl) hexanoyl] -Nn-
Octadecanoylamine, N- [3- (p-hydroxyphenyl) propionyl] -N- (pn-octylbenzoyl) amine, N- [2- (p-hydroxyphenyl) aceto] -N'-n- Dodecanohydrazide, N-
[2- (p-hydroxyphenyl) aceto] -N'-n
-Octadecanohydrazide, N- [3- (p-hydroxyphenyl) propiono] -N'-n-octadecanohydrazide, N- [3- (p-hydroxyphenyl) propiono] -N'-n-docosa Nohydrazide, N- [6-
(P-hydroxyphenyl) hexano] -N'-n-tetradecanohydrazide, N- [6- (p-hydroxyphenyl) hexano] -N'-n-octadecanohydrazide, N- [6- (p -Hydroxyphenyl) hexano]
-N '-(pn-octylbenzo) hydrazide, N-
[11- (p-hydroxyphenyl) undecano] -N
'-N-decanohydrazide, N- [11- (p-hydroxyphenyl) undecano] -N'-n-octadecanohydrazide, N- (p-hydroxybenzo) -N'-n
-Octadecanohydrazide, N- [p- (p-hydroxyphenyl) benzo] -N'-n-octadecanohydrazide, N- [p- (p-hydroxyphenylmethyl) benzo] -N'-n- Octadecanohydrazide,

N- [3- (p-hydroxyphenyl) propyl] -N'-n-octadecyloxamide, N-
[3- (3,4-dihydroxyphenyl) propyl]-
N'-n-octadecyl oxamide, N- [p- (p-
[Hydroxyphenyl) phenyl] -N'-n-octadecyl oxamide, N- [2- (p-hydroxyphenyl) acetyl] -N'-n-octadecyl urea, N-
[2- (p-hydroxyphenyl) ethyl] -N'-n
-Octadecyl urea, N- [3- (p-hydroxyphenyl) propionyl] -N'-n-octadecyl urea,
N- [p- (p-hydroxyphenyl) benzoyl]-
N'-n-octadecyl urea, N- [2- (p-hydroxyphenyl) ethyl] -N'-n-octadecanoyl urea, 4- [2- (p-hydroxyphenyl) ethyl]
-1-n-octadecyl semicarbazide, 1- [2-
(P-hydroxyphenyl) ethyl] -4-n-tetradecylsemicarbazide, 1- [2- (p-hydroxyphenyl) ethyl] -4-n-octadecylsemicarbazide, 1- [2- (p-hydroxyphenyl) acetyl ]
-4-n-tetradecyl semicarbazide, 1- [3-
(P-Hydroxyphenyl) propionyl] -4-n-
Octadecyl semicarbazide, 1- [11- (p-hydroxyphenyl) undecanoyl] -4-n-decylsemicarbazide, 4- [2- (p-hydroxyphenyl)
Ethyl] -1-n-octadecanoyl semicarbazide;
4- [p- (p-hydroxyphenyl) phenyl] -1
-N-octadecanoyl semicarbazide, 1- [2-
(P-Hydroxyphenyl) acetamide] -1-n-
Octadecanoylaminomethane, 1- [3- (p-hydroxyphenyl) propanamide] -1-n-octadecanoylaminomethane, 1- [2- (p-hydroxyphenyl) acetamido] -1- (3- n-octadecylureido) methane, 1- [3- (p-hydroxyphenyl) propanamide] -1- (3-n-octadecylureido) methane, 1- [11- (p-hydroxyphenyl) undecaneamide] -1 -(3-n-decylureido) methane, 1- {3- [2- (p-hydroxyphenyl) ethyl] ureide} -1-n-octadecanoylaminomethane, N- [2- (p-hydroxyphenyl) Ethyl] -N'-n-octadecylmalonamide, 4-n
-Octadecylaminophenol, 4- (1-octadecynyl) phenol, 4- (1,3-octadecadinyl) phenol and the like.

Each of these may be used alone or in combination of two or more. Usually, 5 to 5000 parts by weight, preferably 10 to 3000 parts by weight, per 100 parts by weight of the colorless or pale color leuco dye is used. Can be

Additives A heat-fusible substance can be contained in the reversible thermosensitive recording layer as an additive for adjusting the coloring sensitivity and the decoloring temperature of the reversible thermosensitive recording layer. As the heat-fusible substance, those having a melting point of 60 ° C to 200 ° C are preferable,
Particularly, those having a melting point of 80 ° C to 180 ° C are preferable.
A sensitizer used in general thermosensitive recording paper can also be used. Examples of the sensitizer include waxes such as N-hydroxymethyl stearamide, stearamide, and palmitamide, naphthol derivatives such as 2-benzyloxynaphthalene, and p-benzylbiphenyl and 4-allyloxybiphenyl. Biphenyl derivatives, 1,2-bis (3-methylphenoxy) ethane,
Polyether compounds such as 2,2'-bis (4-methoxyphenoxy) diethyl ether and bis (4-methoxyphenyl) ether; carbonic acid such as diphenyl carbonate, dibenzyl oxalate, and bis (p-methylbenzyl) oxalate; An oxalic acid diester derivative or the like can be added in combination, but is not limited thereto.

Further, a reversible thermosensitive recording layer, an anchor layer (provided between the substrate and the thermosensitive recording layer), a protective layer (provided on the thermosensitive recording layer) or an intermediate layer (protected by the thermosensitive recording layer and the protective layer). Provided between the layers) includes zinc stearate,
Higher fatty acid metal salts such as calcium stearate; waxes such as paraffin, paraffin oxide, polyethylene, polyethylene oxide, stearamide, castor wax; dispersants such as sodium dioctylsulfosuccinate; surfactants; fluorescent dyes Can also be contained.

Substrate The substrate used as the support in the reversible thermosensitive recording medium of the present invention includes paper, coated paper, various nonwoven fabrics, woven fabric, synthetic resin film, synthetic resin laminated paper, synthetic paper, metal foil ,
Glass or the like, or a composite sheet obtained by combining them can be used arbitrarily according to the purpose, and may be transparent, translucent, or opaque, but is not limited thereto. The thickness of the substrate is not particularly limited as long as it can withstand repeated use.
To 1,300 μm, and preferably about 40 to 1,000 μm.

Structure of the reversible thermosensitive recording medium The structure of the reversible thermosensitive recording medium of the present invention is such that a leuco dye / polymer composite type thermosensitive recording layer is provided on a base material, and A protective layer is provided. Further, an anchor layer can be provided between the base material and the heat-sensitive recording layer, or an intermediate layer can be provided between the heat-sensitive recording layer and the protective layer. In the reversible thermosensitive recording layer, in another layer, and / or on the surface on which the reversible thermosensitive recording layer is provided or on the opposite surface, a material capable of recording information electrically, magnetically, and optically is included. May be. Further, a back coat layer may be provided on the surface opposite to the surface on which the reversible thermosensitive recording layer is provided for the purpose of preventing curling and electrification, and may be subjected to an adhesive process or the like.

Method for Preparing Coating Solution The ratio of the total amount (M) of the reversible developer and the electron-donating dye precursor such as leuco dye to the amount (N) of the above-mentioned resin for the heat-sensitive recording layer was determined. Is M / N = 10 / 90-70
/ 30wt%, preferably 15 / 85-60 /
40 wt%, more preferably 20/80 to 50/50
wt% parts. If the total used amount (M) is less than 10 wt%, the coloring density is too low, and if it exceeds 90 wt%, it becomes difficult to form a recording layer. The method for producing a coating liquid from the reversible developer, the leuco dye, and the resin for the heat-sensitive recording layer comprises dissolving or dispersing the reversible developer, the leuco dye, and the additive in a water emulsion of the resin for the heat-sensitive recording layer or the resin. Using a water or organic solvent as a solvent, a solution or dispersion containing the above components (both are referred to as a coating solution) is prepared, and the coating solution is applied to an appropriate substrate surface, and then dried. In addition, the desired leuco dye / polymer composite type thermosensitive recording layer can be formed by UV curing or UV curing. An apparatus such as a ball mill and a homogenizer can be used for preparing the coating liquid.

Formation of Leuco Dye / Polymer Composite Thermosensitive Recording Layer A method for forming each layer (thermosensitive recording layer, anchor layer, intermediate layer, protective layer, etc.) constituting the reversible thermosensitive recording medium of the present invention on a support. Is not particularly limited, and can be formed by a conventional method. As a method of applying the coating liquid,
For example, a coating apparatus such as an air knife coater, a blade coater, a bar coater, and a curtain coater, and various printing machines using a method such as lithographic, letterpress, intaglio, flexographic, gravure, screen, and hot melt can be used. After the coating liquid is applied, besides the usual drying method,
Each layer can be held by UV irradiation, EB irradiation, or the like. These methods can be applied one layer at a time or simultaneously at multiple layers.

Recording and Erasing In the reversible thermosensitive recording medium of the present invention, rapid formation of information such as a color-developed recorded image may be achieved by rapid cooling subsequent to heating. It is sufficient that the cooling rate after heating is low. For example, after heating by an appropriate method, by rapidly cooling by pressing a low-temperature metal block or the like, a colored state can be developed. In addition, when heating is performed for a very short time using a thermal head, a laser beam, or the like, cooling is performed immediately after the heating is completed, so that a color-developed state can be maintained. On the other hand, when heated by a suitable heat source (thermal head, laser light, heat roll, heat stamp, high frequency heating, electric heater, radiant heat from a light source such as a tungsten lamp or halogen lamp, hot air, etc.) for a relatively long time, reversible Since not only the heat-sensitive recording layer but also the support and the like are heated, even if the heat source is removed, the cooling speed is low, and the color becomes a decolored state. Therefore, even if the same heating temperature and / or the same heat source is used, the color development state and the decoloration state can be arbitrarily developed by controlling the cooling rate.

[0080]

Next, the present invention will be described more specifically with reference to examples and comparative examples. The present invention is not limited by these examples. The “parts” in Examples and Comparative Examples
Indicates "parts by weight".

(Preparation of Leuco Dye / Polymer Composite Type Thermosensitive Recording Layer Resin) (Synthesis Example 1) A urethane resin emulsion (Zeneca) NeoRez R-96 (trade name) manufactured by Co., Ltd.
(0, solid content 33 wt%) and 303 g of ion-exchanged water were stirred and heated to 75 ° C. 73 g of methyl methacrylate, 24 g of butyl acrylate, 3-
An emulsion prepared by emulsifying 4 g of methacryloxypropyl trimethochitosilane (A-174, manufactured by Nippon Unicar Co., Ltd.), 5 g of a surfactant (Newcol 707SF, manufactured by Nippon Emulsifier Co., Ltd.) and 60 g of ion-exchanged water, Catalyst aqueous solution (potassium persulfate 0.5 g and ion exchanged water 1
6.5 g of an aqueous solution) was dropped into the reaction vessel over 2 hours. After further reacting for 1 hour, the mixture was cooled to room temperature, and an aqueous emulsion (solid content concentration 43% by weight, pH 7.6, viscosity 7
0 cps (30 ° C.). The glass transition point of the resin is 5
The temperature was 0 ° C., and the particle size of the emulsion was 50 nm.

(Synthesis Example 2) A urethane resin emulsion (trade name: Unicoat UWS-145, manufactured by Sanyo Chemical Co., Ltd., solid content concentration) 286 g (35 wt%) and 32 g of ion-exchanged water were charged and stirred, and heated to 75 ° C. 76 g of methyl methacrylate, 23 g of butyl acrylate, 4 g of 3-methacryloxypropyl trimethochitosilane (A-174, manufactured by Nippon Unicar Co., Ltd.), surfactant (Newcol 707S, manufactured by Nippon Emulsifier Co.)
F) An emulsion prepared by emulsifying 5 g and 60 g of ion-exchanged water in advance and an aqueous solution of a catalyst (an aqueous solution of 0.5 g of potassium persulfate and 16.5 g of ion-exchanged water) were dropped into the reaction vessel over 2 hours. After further reacting for 1 hour, the mixture was cooled to room temperature, and an aqueous emulsion (solid content: 41% by weight, pH:
7.5, viscosity 80 cps (30 ° C.). The glass transition point of the resin is 50 ° C., and the particle size of the emulsion is 40
nm.

(Example 1 of Leuco Dye)
Di-n-butylamino-6-methyl-7-anilinofluoran was used. (Example 1 of reversible developer) N- [3- (p-
[Hydroxyphenyl) propiono] -N'-n-octadecanohydrazide was used. (Mixing method) The resins obtained in Synthesis Examples 1 and 2, Leuco Dye Example 1 and Reversible Developer Example 1 were blended in proportions shown in Table 1 below.
The coating solution for the reversible thermosensitive recording layer was prepared by pulverizing and mixing with a ball mill for 24 hours.

[0084]

[Table 1]

(Preparation of Recording Sheet) A polyethylene terephthalate (PET) sheet (Melinex 339 (100 μm) manufactured by DuPont) was used as a base material.
The reversible heat-sensitive coating solution prepared according to the formulation of the formulation example was coated so as to have a dry coating amount of 6 g / m ² , dried, and then heat-treated at 110 ° C. for 1 hour to obtain a coated sheet. .

(Coating of Protective Layer) On the reversible thermosensitive recording layer of the coated sheet obtained above, Aronix M8 was used as a protective layer.
030 (manufactured by Toa Gosei Chemical Industry Co., Ltd.), 5 parts of N-vinyl-2-pyrrolidone, 5 parts of Irgacure 500 (manufactured by Ciba Geigy), and 5 parts of Mizukasil P-527 (manufactured by Mizusawa Chemical Co., Ltd.) After applying an ultraviolet curable resin obtained by sufficiently stirring to a concentration of 3 g / m ² , the resin was cured by an ultraviolet irradiation device. Next, heat treatment was performed at 100 ° C. for 1 hour to obtain a reversible thermosensitive recording medium having a protective layer. The following evaluation test was performed on the reversible thermosensitive recording medium manufactured as described above.

(Recording / Erasing Test Method) Using the reversible thermosensitive recording media obtained in Examples 1 and 2 and Comparative Examples 1 and 2, an applied pulse width of 2.0 milliseconds was applied by a 8 dot / mm thermal head manufactured by Kyocera. Printing was performed under the conditions of an applied voltage of 21 volts, and the obtained color image was measured as a color density using a densitometer Macbeth RD918. Further, a heat stamp was applied to the obtained color image portion, and the color was erased by heating at 120 ° C. for 1 second.
Further, the color development density and the color erasure density after repeating the color development and the color erasure 60 times were measured. In addition, the portion where printing was repeated 60 times was observed with an optical microscope, and the degree of damage on the printing recording surface was evaluated. The evaluation criteria are as follows. ：: No damage on the recording surface was observed, and good. △: Slight printing scratches were observed on the recording surface. ×: Many destructions and scratches were observed on the recording printing surface. The measurement was performed based on "scratch test". A test was performed in which a cellotape (registered trademark) was strongly adhered to the recording print surface and peeled off once. The evaluation criteria are as follows. ：: very good without any delamination on the recording surface △: slight delamination on the recording surface ×: destruction of the layer on the recording printing surface

The obtained reversible thermosensitive recording medium was put in water for 100 hours.
Immediately after immersion for a time, the strength of the recording surface is measured using the "pencil scratch test".
The measurement was performed based on. The evaluation results are shown in Tables 2 and 3.

[0089]

[Table 2]

[0090]

[Table 3]

From Table 2, it can be seen that Examples 1 and 2 in which the resin matrix of the reversible thermosensitive recording layer was changed to the resin matrix of the present invention were excellent in color density and color erasing density even after many repetitions, and had good image contrast. It turns out that it has sufficient durability. On the other hand, in Comparative Examples 1 and 2, although sufficient color development density and color erasing density were obtained at the initial stage,
When coloring and decoloring were repeatedly performed, the contrast of the image was lowered, and as is apparent from Table 3, destruction of the reversible thermosensitive recording layer presumably caused by the thermal head was observed. Thereby, a clear difference is recognized between the example and the comparative example, and it is confirmed that the present invention has a great effect.

[0092]

The reversible thermosensitive recording medium of the present invention can be changed to a decolored state by developing a color with thermal energy of a thermal head or the like and heating again. And
Such coloring and erasing can be performed repeatedly, and the color developing and erasing states can be maintained at room temperature. Further, the reversible thermosensitive recording medium of the present invention,
Even if coloring and decoloring are repeatedly performed, there is little damage and it can be used practically sufficiently.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a reversible thermosensitive recording display medium of the present invention.

[Explanation of symbols]

 Reference Signs List 1 resin matrix 2 leuco dye 3 developer 5 base material 7 protective layer

Claims (11)

[Claims] 1. A resin used for a leuco dye / polymer composite type thermosensitive recording layer for a reversible thermosensitive recording medium, wherein the resin is a polymer of a urethane resin (A) and a polymerizable unsaturated monomer. (B) and a leuco dye /
Polymer composite type thermosensitive recording layer resin. 2. The method according to claim 1, wherein the polymer (B) is dispersed in the urethane resin (A) in the form of particles.
The leuco dye / polymer composite type thermosensitive recording layer resin described in the above. 3. An aqueous emulsion containing polymer particles having a core-shell structure or a microdomain structure composed of a urethane resin (A) and a polymer (B). 3. The resin for a leuco dye / polymer composite type thermosensitive recording layer according to 1 or 2. 4. The leuco dye according to claim 1, wherein the polymer (B) contains at least one polymerizable unsaturated monomer having a hydrolyzable silyl group. / Resin for polymer composite type thermosensitive recording layer. 5. Another polymer comprising a polymerizable unsaturated monomer (b) having at least one kind of carboxyl group and another polymerizable monomer (c) is further added. The resin for a leuco dye / polymer composite type thermosensitive recording layer according to claim 1. 6. The leuco dye according to claim 1, wherein the resin is substantially incompatible with the leuco dye and / or the reversible developer and forms a phase-separated structure. Polymer composite type thermosensitive recording layer resin. 7. A leuco dye / polymer composite type obtained by dispersing a leuco dye and a reversible developer in the resin for a leuco dye / polymer composite type thermosensitive recording layer according to claim 1. Thermal recording layer. 8. The leuco dye / polymer composite type thermosensitive recording according to claim 7, wherein the compounding ratio of (leuco dye + reversible developer) / resin is 10/90 to 70/30 wt%. layer. 9. A reversible thermosensitive recording medium comprising the leuco dye / polymer composite type thermosensitive recording layer according to claim 7 provided on a substrate. 10. The reversible thermosensitive recording medium according to claim 9, wherein a protective layer is provided on the upper surface of the reversible thermosensitive recording layer. 11. A water emulsion of the resin for a leuco dye / polymer composite type thermosensitive recording layer according to any one of claims 1 to 6, and the leuco dye and a reversible developer according to claim 7 dispersed in water. A method for producing a leuco dye / polymer composite type heat-sensitive recording layer by applying a coating solution obtained by the above-mentioned method onto a substrate and then drying.