JP2002088038A - New compound and reversible thermally sensitive recording material comprising the same and reversible thermally sensitive recording medium having the same material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new compound having high rewriting characteristics, stability of printing and erasing characteristics with time and high heat resistance and added to a reversible thermally sensitive recording material and the reversible thermally sensitive recording material comprising the compound and to provide a reversible thermally recording medium having the material. SOLUTION: This new compound is characterized in that the compound is represented by the following general formula [1] or [2]. R1-X-Ar-R2-Y-R3 [1] in the general formula [1], R1 group and R3 group denote each a >=1C organic group; R2 group is a bivalent organic group selected from >=1C groups; X group and Y group are each any bivalent group of oxygen atom, sulfur atom, an ester, a thiourea, urea, a thioamide, an amide, a diacylamine, a diacylhydrazine and an oxalic diamide; Ar group is any of phenyl group, naphthyl group and biphenyl group) or R1-X-Ar-Y-R3 [2].

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel compound, a reversible thermosensitive recording material containing the compound, and a reversible thermosensitive recording medium having the reversible thermosensitive recording material. A novel compound to be added to heat-resistant materials such as a reversible thermosensitive recording material that increases the preservability of information while maintaining characteristics, particularly heat resistance, and a reversible thermosensitive recording material containing this compound, and the reversible thermosensitive recording material. The present invention relates to a reversible thermosensitive recording medium.

[0002]

2. Description of the Related Art A reversible thermosensitive recording medium capable of recording information such as characters and images by heating with a heating means such as a thermal head has been used. Such a reversible thermosensitive recording medium has a reversible thermosensitive recording material containing, as components, a dye precursor which is an electron-donating compound and a color-reducing agent which is an electron-accepting compound. The medium is heated by the above-described heating means, by reacting the leuco dye of the electron-donating compound with the color-reducing agent of the electron-accepting compound, so that the information such as the characters can be visually confirmed or printed. It uses the fact that the information that has been erased can be erased again. Such a reversible thermosensitive recording medium can be rewritten / erased by reheating.

[0003] The coloring and decoloring will be described with reference to FIG. FIG. 1 shows the relationship between the color density and the temperature of a reversible thermosensitive recording medium. First, the reversible thermosensitive recording medium is in a decolored state at room temperature (state A in the figure), and when the temperature is raised from this state, the leuco dye and the color-degrading agent melt and mix from the temperature T2. , And begins to develop color (state B in the figure). Here, T2 is a coloring temperature. At this time, when the reversible thermosensitive recording medium is rapidly cooled to room temperature, the color development state is maintained (state C in the figure). Next, as the temperature of the reversible thermosensitive recording medium is increased, the color density starts to decrease from the temperature T1 and becomes a decolored state (state D in the figure). The decolored state is maintained (state A in the figure). Here, T1 is the erasing temperature, and the temperature from T1 to T2 is the erasing temperature range.

When a reversible thermosensitive recording medium is made of a color-reducing agent having a low melting point or a low crystal transition point, the heat capacity required for erasing information is reduced. It will be good. That is, since the heat capacity required for erasing information by the thermal head is small, the overwrite characteristics of the information recorded on the reversible thermosensitive recording material, particularly the erasability, are high. However, when such a color-reducing agent is used, the decoloring temperature T1 becomes low, so that
Information can be easily lost. In other words, a reversible thermosensitive recording medium using a color-reducing agent having a low melting point or a low crystal transition point improves the overwrite characteristics, but the information is easily erased when exposed to a high-temperature state for a long period of time. However, the preservability of information such as characters, especially the preservability (heat resistance) of the information when heat is applied, is inferior.

Conversely, when a reversible thermosensitive recording medium is made of a color-developing agent having a high melting point or a high crystal transition point, the erasing temperature T1 is increased, so that the heat resistance is improved, but the heat capacity required for erasing is increased. Therefore, the overwrite characteristics are deteriorated.
This is because heating for a very short time using a thermal head cannot provide the reversible thermosensitive recording medium with the heat capacity necessary for erasing information, and thus requires long-time heating to erase information. is there.

[0006]

However, in the reversible thermosensitive recording medium according to the prior art comprising a leuco dye and a color-reducing agent, as described above, rewrite characteristics such as overwrite characteristics and storability of information, particularly heat resistance. It is difficult to achieve both. That is, since both the rewrite characteristics and the heat resistance depend on the melting point or crystal transition point of the color-developing agent, it is difficult to solve this problem even if the color-developing agent is improved.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems. By adding it to a reversible thermosensitive recording material, the rewrite property of the reversible thermosensitive recording material (medium) can be maintained well. It is another object of the present invention to provide a novel compound capable of improving the storage stability of information, particularly heat resistance, and effectively preventing the loss of information and the like.

Further, the present invention is characterized in that there is no change over time in the printing and erasing characteristics (printing / erasing energy range) which is one of the rewriting characteristics of the reversible thermosensitive recording material (stability of the printing and erasing characteristics over time). It is an object of the present invention to provide a novel compound that imparts high heat resistance while maintaining good heat resistance.

Further, the present invention provides a reversible thermosensitive recording material having good rewrite characteristics and stability over time of printing and erasing characteristics and high heat resistance by containing such a novel compound. The purpose is to provide.

Further, the present invention relates to a reversible thermosensitive recording material using a reversible thermosensitive recording material having such high rewrite characteristics, stability over time of printing and erasing characteristics, and high heat resistance. The purpose is to provide a medium.

[0011]

Means for Solving the Problems In order to achieve the object, the invention of the novel compound according to claim 1 is characterized by being represented by the following general formula [1]. R ₁ -X-Ar-R ₂ -YR ₃ [1] (In the general formula [1], R ₁ and R ₃ are
Represents an organic group having 1 or more carbon atoms, each of which may be the same or different, and the R ₂ group is a linear or branched alkylene group which may have a substituent; A divalent organic group selected from a group having 1 or more carbon atoms including a divalent hydrocarbon group, a divalent aromatic ring that forms a ring independently of a naphthol ring, and the like, wherein the group is aromatic When forming a ring, a hetero ring may be formed;
The group and the Y group are any divalent group of oxygen atom, sulfur atom, ester, thiourea, urea, thioamide, amide, diacylamine, diacylhydrazine, and oxalic acid diamide. The Ar group may be any of a phenyl group, a naphthyl group, and a biphenyl group. )

The invention of a novel compound according to claim 2 is characterized by being represented by the following general formula [2]. R ₁ —X—Ar—Y—R ₃ [2] (In the general formula [2], R ₁ and R ₃ are
Represents an organic group having 1 or more carbon atoms, which may be the same or different, and each of the X group and the Y group is an oxygen atom, a sulfur atom, an ester, a thiourea, a urea, a thioamide, an amide, a diacylamine, a diacylhydrazine , Oxalic acid diamide, which may be the same or different, and the Ar group is a phenyl group, a naphthyl group, or a biphenyl group. )

The invention of a reversible thermosensitive recording material according to claim 3 is characterized by having the novel compound according to claim 1 or 2, an electron donating compound and an electron accepting compound.

According to a fourth aspect of the present invention, in the reversible thermosensitive recording material according to the third aspect, the novel compound contains 2.5 to 15% by weight of the electron-accepting compound.

[0015] The invention of a reversible thermosensitive recording medium according to claim 5 is a reversible thermosensitive recording medium comprising at least a reversible thermosensitive recording layer provided on a base material. A reversible thermosensitive recording material as described in 3 or 4 above.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the novel compound according to the present invention, a reversible thermosensitive recording material containing the same, and a reversible thermosensitive recording medium will be described in detail with reference to embodiments. First, the novel compound according to the present invention will be described.

[New Compound] The compounds represented by the following general formulas [1] and [2] are new compounds. R ₁ -X-Ar-R ₂ -YR ₃ [1] R ₁ -X-Ar-YR ₃ [2]

In the above general formula [1], R₁Group and
R_ThreeThe group represents an organic group having 1 or more carbon atoms.
May be one or different, R_TwoGroup has a substituent
A linear alkylene group or a branched alkylene
Group, divalent hydrocarbon group having a double bond, naphthol
Charcoal containing divalent aromatic ring, etc. that forms a ring independently of the ring
A divalent organic group selected from groups having a prime number of 1 or more,
When a group forms an aromatic ring, it forms a heterocycle
X and Y groups may be an oxygen atom, a sulfur atom,
Ter, thiourea, urea, thioamide, amide, diacyl
Amine, diacylhydrazine, oxalic acid diamide
These are divalent groups, each of which is the same or different
An Ar group may be a phenyl group, a naphthyl group,
Enyl group. Ar group is a phenyl group
At this time, (R ₁-X-) group is (-
R_Two-Y-R_Three) Ortho, meta, para position relative to the group
And the Ar group may be a naphthyl group or a naphthyl group.
Or a biphenyl group, in the above formula [1]
(R₁-X-) group is (-R_Two-Y-R_Three) Identical to the group
It may be present on a ring or on another ring. Ma
In the above general formula [2], R₁Group, R_ThreeGroup, X
The group, the Y group, and the Ar group are represented by the general formula [1].
R₁Group, R_ThreeAnd X, Y, and Ar groups, respectively.
Is the same. When the Ar group is a phenyl group,
(R) in [2]₁-X-) group is (-YR)_Three) Group
Exists in any of the ortho, meta and para positions with respect to
And the Ar group is a naphthyl group or a biphenyl group
In some cases, (R) in the above formula [2]₁-X-) group is
(-YR_Three) Group may be on the same ring as
May be present.

The organic group referred to in the present invention is defined as (1) an aliphatic group (provided that hydrogen is substituted with a halogen, a hydroxyl group, a carboxyl group, a sulfone group, an amino group, a thiirane group, a phosphate group, or the like). Good), (2) an aliphatic group, or (3) a heterocyclic group.

(1) The aliphatic group preferably has 1 to 33 carbon atoms and is a linear, branched or cyclic alkyl, alkenyl, alkynyl or aralkyl group.

As the alkyl group, specifically, for example, methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-octyl
-Nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, isopropyl, 2-methylpropyl, 1-methylpropyl, 3-methylbutyl, 2-methylbutyl, 1-
Methylbutyl, 4-methylpentyl, 3-methylpentyl, 2-methylpentyl, 1-methylpentyl, 5-methylhexyl, 4-methylhexyl, 3-methylhexyl, 2-methylhexyl, 1-methylhexyl, 6-methyl Heptyl, 5-methylheptyl, 4-methylheptyl, 3-methylheptyl, 2-methylheptyl, 1-methylheptyl, 7-methyloctyl, 6-methyloctyl, 5-methyloctyl, 4-methyloctyl, 3-methyl Octyl, 2-methyloctyl, 1-methyloctyl, 8-methylnonyl, 7-methylnonyl, 6-methylnonyl, 5-methylnonyl, 4-methylnonyl, 3-methylnonyl, 2-methylnonyl, 1-methylnonyl,
Examples include groups such as 3,7-dimethyloctyl and 3,7,11-trimethyldodecyl. Examples of the alkenyl group include, for example, 2-propenyl, 3-butenyl, 4-pentenyl, 5-hexenyl, 6-heptenyl, 7-octenyl, 8-nonenyl, 9-decenyl,
Examples include linear alkenyl groups such as 0-undecenyl, 11-dodecenyl and 12-tridecenyl, and branched alkenyl groups such as 1-methyl-2-propenyl and 3-methyl-3-butenyl. Specific examples of the alkynyl group include linear alkynyl groups such as 2-propynyl, 3-butynyl, 5-hexynyl and 7-octynyl, and branched alkynyl groups such as 1-methyl-2-propynyl. Can be Specific examples of the aralkyl group include a benzyl group and a phenethyl group.

In addition, at least one of the above-mentioned hydrocarbon groups has at least one of the following bonding parts -O-, -CO
-, -S-, -SO-, -NH-, alone or a group formed by bonding them to each other via a bonding portion bonded and complexed to each other.

(2) The aromatic carbocyclic group preferably has 6 to 30 carbon atoms, particularly a monocyclic or condensed aryl group having 6 to 20 carbon atoms, such as a phenyl group,
And a naphthyl group.

(3) As the heterocyclic group, a 3- to 10-membered saturated or unsaturated heterocyclic group containing at least one of a nitrogen atom, an oxygen atom and a sulfur atom is preferably used. These may be monocyclic or may form a condensed ring with another aromatic or heterocyclic ring.

More preferably used as the heterocyclic group are 5- to 6-membered aromatic heterocyclic groups such as pyridyl, furyl, thienyl, thiazolyl, imidazolyl and benzimidazolyl. can give.

The above-described aliphatic group, aromatic carbocyclic group and heterocyclic group may each have a substituent.
Examples of the substituent include the following. Representative substituents include, for example, alkyl groups, aralkyl groups, alkenyl groups, alkynyl groups, aryl groups, alkoxy groups,
Aryloxy group, amino group, acylamino group, ureido group, urethane group, sulfonylamino group, sulfamoyl group, carbamoyl group, sulfonyl group, sulfinyl group, alkyloxycarbonyl group, aryloxycarbonyl group, acyl group, acyloxy group, phosphoric acid Examples include an amide group, a diacylamino group, an imide group, an alkylthio group, an arylthio group, a halogen atom, a cyano group, a sulfo group, a carboxy group, a hydroxy group, a phosphono group, a nitro group, and a heterocyclic group. These groups may be further substituted. When there are two or more substituents, they may be the same or different.

Examples of the R ₂ group include C ₁ -C ₁₈ such as methylene, ethylene, propylene, butylene, pentene, hexene, heptene, octene, nonylene and decene. Linear alkylene group,
Isopropylene group, isobutylene group, isopentene group,
Isohexene group, isoheptene group, isooctene group, isononyl group, branched alkylene group such as isodecene group,
A cycloalkylene group such as a cyclopropenylene group or a cyclopentenylene group; (these cycloalkylene groups may have a monovalent substituent described in the present specification).

A substituted alkylene group; a part of the hydrogen bonded to the carbon constituting the divalent hydrocarbon group is a monovalent group, for example, a halogen group such as fluorine, chlorine, bromine or iodine, --COOM (M Is hydrogen or a monovalent metal: N
a, K, etc. These M are also included in the monovalent group), -NR
₂₁ R ₂₂ (R _{21 to} R ₂₂ are hydrogen or a (cyclo) alkyl group), an alkylene group having a hydroxyl group or the like.

The R ₂ group which may have a double bond includes —CH ＝ CH—, —CH ＝ CCl—, and —CCl
= CCl -, - C (COOH ) = CH -, - CCH 3 =
C (COOH) -, - CCH 3 = C (COOCH 3)
—, —CH ＝ C (COOH) — and the like. The hydrogen bonded to these carbons in the aforementioned groups may be substituted with a monovalent group.

Examples of the compound represented by the general formula [1] include a compound represented by the following formula [3].

[0031]

Embedded image

That is, in the above formula [3], the R ₁ group is CH ₃ — (CH ₂ ) _n1 , the Y group is COO,
Ar group is a phenyl group, a R2 group is (CH _{2) n2,} X groups are CONHCONH, R ₃ group is (C
H ₂ ) _n3 —CH ₃ can be exemplified. Here, n1 and n3 may be the same or different and are integers of 1 to 32, and n2 is an integer of 1 to 18.

The compound represented by the general formula [1] according to the present invention includes a compound represented by the following formula [4] and a compound represented by the following formula [5]
Can be produced by reacting with the compound represented by the following formula, but is not limited to this synthesis method. (In the above formula, Ar, R ₁ , R ₂ , R ₃ and Y are each the same as in the above formula [1]. Z is a reactive species such as a halogen atom. Q is X by a dehydration condensation reaction. A group serving as a group. In the formula [4], the (HO-) group may be a (HS-) group or the like.)

That is, the compound represented by the above formula [4] is dissolved in a polar solvent, and the compound represented by the above formula [5] dissolved in a nonpolar solvent is added thereto under anaerobic conditions. The compound represented by the formula [1] can be obtained.

The compound represented by the general formula [2] according to the present invention is produced by reacting a compound represented by the following formula [6] with a compound represented by the following formula [7]. But it is not limited to this synthesis method. (In the above formula, Ar, R ₁ , R ₃ , Q, Y, and Z are the same as those in the aforementioned reaction formula (1).)

That is, the compound represented by the above formula [6] is dissolved in a polar solvent, and the compound represented by the above formula [7] dissolved in a nonpolar solvent is added thereto under anaerobic conditions.
The compound represented by the above formula [2] can be obtained.

[Reversible Thermosensitive Recording Material] Next, the case where the novel compound according to the present invention is used for a reversible thermosensitive recording material will be described. This reversible thermosensitive recording material is a layer containing the novel compound as described above, a dye precursor, and a color-depressing agent, and reversibly repeats color development / decoloration by application of heat. The electron donating compound is usually a colorless or pale color, for example, a leuco dye. In addition, the electron accepting compound,
It is a color-reducing agent, and causes a reversible color change in the dye precursor, which is an electron-donating compound, depending on the difference in cooling temperature after heating.

<New Compound> The reversible thermosensitive recording material according to the present invention imparts good rewrite characteristics and the same erasing characteristics of printing and erasing as before, and has high heat resistance (preservation of information).
Having a novel compound. As the novel compound contained in the reversible thermosensitive recording material, one of the compounds represented by the general formulas [1] and [2] can be used. Can be used.

The novel compound represented by the above general formula [1] or [2] is contained in an amount exceeding 0 wt% with respect to the weight of the color-reducing agent, and preferably has high heat resistance.
wt% or more, more preferably in the range of 2.5 wt% to 30 wt% in which good erasing density can be obtained, and especially 2.5 wt% in which good printing density can be obtained.
% To 15 wt%.

<Dye Precursor> The dye precursor used in the reversible thermosensitive recording material according to the present invention includes pressure-sensitive recording paper,
Dye precursors used for reversible thermosensitive recording paper, photosensitive pressure-sensitive paper (registered trademark), current-reversible thermosensitive recording paper, thermosensitive recording paper, and the like are exemplified. The present invention is not particularly limited to these. For example, the following are mentioned.

(1) Triarylmethane compounds 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-methylindol-3-yl) phthalide, 3- (p-dimethylaminophenyl) -3- (2-phenylindole-
3-yl) phthalide, 3,3-bis (1,2-dimethylindol-3-yl) -5-dimethylaminophthalide, 3,3-bis (1,2-dimethylindole-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) benzhydryl benzyl ether, N-chlorophenyl leuco auramine, N-2,4,5-trichlorophenyl leuco auramine and the like.

(3) Xanthene compounds Rhodamine B anilinolactam, rhodamine B-p-chloroanilinolactam, dialkoxyfluoran, such as 3,6-dimethoxyfluoran, aminofluoran compounds; for example, 3-diethylamino- 3-diethylamino-7-phenylfluoran, 3-diethylamino-7-chlorofluorane, 3-diethylamino-6-, such as 7-dibenzylaminofluoran and 3-diethylamino-7-octylaminofluoran.
Chloro-7-methylfluoran,

Anilinofluoran compound; for example, 3
-Diethylamino-7- (3,4-dichloroanilino)
Fluoran, 3-diethylamino-7- (2-chloroanilino) fluoran, 3-diethylamino-6-methyl-7-anilinofluoran, 3- (N-ethyl-N-tolyl) amino-6-methyl-7-ani Linofluoran,
3- (N-ethyl-N-tolyl) amino-6-methyl-7-phenethylfluoran, 3-diethylamino-7- (4-nitroanilino) such as 3-piperidino-6-methyl-7-anilinofluoran Fluoran, 3-dibutylamino-6-methyl-7-anilinofluoran, 3-
(N-methyl-N-propyl) amino-6-methyl-7
-Anilinofluoran, 3- (N-ethyl-N-isoamyl) amino-6-methyl-7-anilinofluoran,
3- (N-methyl-N-cyclohexyl) amino-6
Methyl-7-anilinofluoran, 3- (N-ethyl-
N-tetrahydrofuryl) amino-6-methyl-7-anilinofluoran;

Benzofluoran compounds; for example, 3-
Azaphthalide-based compounds such as dialkylamino-7,8-benzofluoran; 3- (4-diethylamino-2
-Ethoxyphenyl) -3- (1-ethyl-2-methylindol-3-yl) -4-azaphthalide and the like.

(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-propylspirobenzopyran and the like.

The following formulas [8] and / or [9]
May be used.

[0049]

Embedded image

The usually colorless or pale color dye precursor is
It can be appropriately selected from the compounds described above according to the purpose. The dye precursors may be used as a mixture of two or more kinds.

<Eye-lowering agent (electron-accepting compound)>
The color-reducing agent as the electron-accepting compound used in the present invention can be used in a wide range. For example, a phenolic compound having a long-chain alkyl group having 11 or more carbon atoms, A naphthol-based compound having a long-chain alkyl group described above can be used, and the long-chain alkyl group may include a hetero atom (N, Cl, F, O, or the like). Specifically, N- (p-hydroxyphenyl) -N'-n-octadecylthiourea,
N- (p-hydroxyphenyl) -N'-n-octadecylurea, N- (p-hydroxyphenyl) -N'-n
-Octadecylthioamide, 4'-octadecaneanilide, 2-octadecylterephthalic acid, N-octadecyl (p-hydroxyphenyl) amide, N- (p-hydroxybenzoyl) -N-octadecanoylamine, N-
[3- (p-hydroxyphenyl) propiono] -N '
-Octadecanohydretide, N-[(p-hydroxyphenyl) methyl] -n-octadecylamide, N-
[(P-hydroxyphenyl) methyl] -n-octadecylurea, N-[(p-hydroxyphenyl) methyl]
—N′-n-octadecyl oxamide and the like.

Further, the following color-reducing agents can be used. N-pentacosyl (p-hydroxyphenyl) amide, N-hexacosyl (p-hydroxyphenyl) amide, N-heptacosyl (p-hydroxyphenyl) amide,
N-octacosyl (p-hydroxyphenyl) amide, N-nonakosyl (p-hydroxyphenyl) amide, N-triacontyl (p-hydroxyphenyl) amide, N-hentriacontyl (p-hydroxyphenyl) amide, N-dotriacontyl ( Amide compounds such as p-hydroxyphenyl) amide, N-tetratriacontyl (p-hydroxyphenyl) amide,

N- (p-hydroxybenzoyl) -N-hexacosanoylamine, N- (p-hydroxybenzoyl) -N-
Heptacosanoylamine, N- (p-hydroxybenzoyl) -N-octacosanoylamine, N- (p-hydroxybenzoyl) -N-nonacosanoylamine, N- (p-hydroxybenzoyl) -N-triaconta Noylamine, N- (p-
Diacylamine compounds such as hydroxybenzoyl) -N-hentriacontanoylamine, N- (p-hydroxybenzoyl) -N-dotriacontanoylamine, N- (p-hydroxybenzoyl) -N-tetratriacontanoylamine ,

N- [3- (p-hydroxyphenyl) propiono] -N'-hexacosanohydrazide, N- [3- (p-hydroxyphenyl) propiono] -N'-heptacosanohydrazide, N- [ 3- (p-hydroxyphenyl) propiono] -N'-
Octacosanohydrazide, N- [3- (p-hydroxyphenyl) propiono] -N'-nonacosanohydrazide, N- [3-
(P-hydroxyphenyl) propiono] -N'-triacontanohydrazide, N- [3- (p-hydroxyphenyl) propiono] -N'-hentriacontanohydrazide, N- [3-
Diacylhydrazine compounds such as (p-hydroxyphenyl) propiono] -N'-dotriacontanohydrazide, N- [3- (p-hydroxyphenyl) propiono] -N'-tetratriacontanohydrazide,

N-[(p-hydroxyphenyl) methyl] -n
-Pentacosylamide, N-[(p-hydroxyphenyl)
Methyl] -n-hexacosylamide, N-[(p-hydroxyphenyl) methyl] -n-heptacosylamide, N-[(p-
(Hydroxyphenyl) methyl] -n-octacosylamide, N-[(p-hydroxyphenyl) methyl] -n-nonacosylamide, N-[(p-hydroxyphenyl) methyl] -n
-Triacontylamide, N-[(p-hydroxyphenyl) methyl] -n-hentriacontylamide, N-[(p-
Amide compounds such as hydroxyphenyl) methyl] -n-dotriacontylamide and N-[(p-hydroxyphenyl) methyl] -n-tetratriacontylamide;

N-[(p-hydroxyphenyl) methyl]-
N'-n-pentacosyl urea, N-[(p-hydroxyphenyl) methyl] -N'-n-hexacosyl urea, N-[(p-hydroxyphenyl) methyl] -N'-n-heptacosyl urea, N-
[(P-hydroxyphenyl) methyl] -N'-n-octacosylurea, N-[(p-hydroxyphenyl) methyl] -N'-n-
Nonacyl urea, N-[(p-hydroxyphenyl) methyl] -N'-n-triacontyl urea, N-[(p-hydroxyphenyl) methyl] -N'-n-hentria contyl urea, N-
[(P-hydroxyphenyl) methyl] -N'-n-dotriacontyl urea, N-[(p-hydroxyphenyl) methyl]-
Urea compounds such as N'-n-tetratriacontyl urea,

N-[(p-hydroxyphenyl) methyl]-
N'-n-pentacosyl oxamide, N-[(p-hydroxyphenyl) methyl] -N'-n-hexacosyl oxamide, N-
[(P-hydroxyphenyl) methyl] -N'-n-heptacosyloxamide, N-[(p-hydroxyphenyl) methyl]
-N'-n-octacosyl oxamide, N-[(p-hydroxyphenyl) methyl] -N'-n-nonakosyl oxamide, N-
[(P-hydroxyphenyl) methyl] -N'-n-triacontyl oxamide, N-[(p-hydroxyphenyl) methyl] -N'-n-hentria contyl oxamide, N-[(p- [Hydroxyphenyl) methyl] -N'-n-dotriacontyloxamide, N-[(p-hydroxyphenyl) methyl] -N'-
Oxalic acid diamide compounds such as n-tetratriacontyl oxamide and the like can be mentioned.

Further, compounds represented by the following chemical formulas can be mentioned.

[0059]

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In the above general formula [10], k is 1,
It is an integer of 2 or 3, preferably 1. Also O
The H group and the R ₄ group to be described later form 2 which forms a naphthol ring.
It may be in any of the two rings and may be on the same ring or on another ring. Furthermore, the OH group is 2
When present, one or more may be on the same ring as R ₄ and the remaining OH groups may be on another ring.

In the general formula [10], R ₄ is preferably a group having an aliphatic hydrocarbon having 11 or more carbon atoms, and is preferably a monovalent group represented by the formula —R ₅ ER ₆ or —ER _6. Group. As the R ₅ group, a divalent hydrocarbon group which may have a substituent, for example, a linear or branched alkylene group having 1 to 10 carbon atoms, a divalent hydrocarbon having a double bond And a divalent group containing a divalent aromatic ring which forms a ring independently of a naphthol ring.
When forming an aromatic ring, the ring may be formed together with a hetero atom.

Examples of such R ₅ groups include C ₁ -C ₁₀ such as methylene, ethylene, propylene, butylene, pentene, hexene, heptene, octene, nonylene, and decene. Linear alkylene group, isopropylene group, isobutylene group, isopentene group, isohexene group, isoheptene group, isooctene group, isononyl group, branched alkylene group such as isodecene group, and further, cyclopropenylene group, cyclopentenylene group (These cycloalkylene groups may have a monovalent substituent described in this specification.)

A part of the hydrogen bonded to the carbon constituting the divalent hydrocarbon group is a monovalent group, for example, a halogen group such as fluorine, chlorine, bromine or iodine, --COOM (M Is hydrogen or a monovalent metal: N
a, K, etc. These M are also included in the monovalent group), -NR
₇ R ₈ (R _{7 to} R ₈ are hydrogen or a (cyclo) alkyl group), an alkylene group having a hydroxyl group or the like.

The R ₅ group which may have a double bond includes —CH ＝ CH—, —CH ＝ CCl—, and —CCl
= CCl -, - C (COOH ) = CH -, - CCH 3 =
C (COOH) -, - CCH 3 = C (COOCH 3)
—, —CH ＝ C (COOH) — and the like. The hydrogen bonded to these carbons in the aforementioned groups may be substituted with a monovalent group.

D represents -CONH-, -NHCO-, -C
ONHCO-, -NHCOCONH- or -CONH
It is a divalent group selected from NHCO- groups.

The R ₆ group is a group having an aliphatic hydrocarbon having 10 or more, preferably 11 or more carbon atoms, and includes the following groups.

[0067]

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As the naphthol group-containing electron-accepting compound, the following compounds are particularly preferably selected.

[0069]

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In the above formula [11], p is an integer of 0 to 10, for example, p = 0, 1, 2, and 3. From the viewpoint of obtaining better color developing performance and erasing performance, p is preferably p. =
It is an integer of 1 to 3. l is an integer of 10 or more, for example, l
= An integer from 10 to 100, preferably l = 10 to 50
Is an integer. That is, in the formula [11], when p is 0, l is an integer of 10 or more, for example, l = 10
In the same manner, when p is 1, l is an integer of 10 or more, for example, l is an integer of 10 to 100, preferably l is an integer of 10 to 50. When p is 2, l is an integer of 10 or more, for example, an integer of l = 10 to 100, preferably 1 = 10 to 50, and when p is 3, l is an integer of 10 or more; For example, l = 10-1
It is shown in the above formula [11] that an integer up to 00, preferably an integer of l = 10 to 50. Such a compound can be specifically exemplified as a naphthol group-containing electron-accepting compound.

Further, there may be mentioned compounds represented by the following chemical formula.

[0072]

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In the general formula [12], g is 1 or 2, and preferably 1. Further, the OH group may be present on any of the two rings constituting the naphthol ring. The same applies to the case where there are two OH groups. j is 10
Is an integer greater than or equal to.

As such a naphthol compound having an amide group at the β-position, the following compounds are particularly preferably selected.

[0075]

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The above formula [12] or [13] to [14]
In the formula, r is an integer of 10 or more. Preferably, r is 1
An integer from 0 to 32, more preferably r is 10
An integer from 20 can be selected.

The electron accepting compound used in the present invention can be used alone or in combination of two or more.

The quantitative ratio of the electron-donating compound leuco dye and the electron-accepting compound microcoloring agent contained in the reversible thermosensitive recording material is appropriately selected according to the combination of the compounds used. However, the color-depressing agent can be used in the range of 0.5 to 20 mol per mol of the leuco dye, and is preferably used in an amount of 1.0 to 10 mol from the viewpoint of obtaining a good color density. Can be Within the above-mentioned range, a reversible thermosensitive recording material having good characteristics at the time of color development and color reduction, and in particular, having less heat deterioration can be obtained.

<Other Resins> In the present invention, as the reversible thermosensitive recording material, the above-mentioned leuco dye which is an electron-donating compound, and a color-reducing agent which is an electron-accepting compound,
Although the above-mentioned novel compounds are mainly used, preferably, the following binder resins and the like are also used.

Examples of the binder resin include starches, hydroxyethylcellulose, methylcellulose, carboxymethylcellulose, gelatin, casein, polyvinyl alcohol, modified polyvinyl alcohol, polyacrylic acid metal salts such as sodium polyacrylate, and acrylic acid amide / acrylic acid ester. Water-soluble polymers such as polymers, acrylamide / acrylate / methacrylic acid terpolymer, alkali salts of styrene / maleic anhydride copolymers, alkali salts of ethylene / maleic anhydride copolymers, poly Latexes such as vinyl acetate, polyurethane, polyacrylate, styrene / butadiene copolymer, acrylonitrile / butadiene copolymer, methyl acrylate / butadiene copolymer, ethylene / vinyl acetate copolymer, etc. In addition, since a reversible heat-sensitive recording layer having excellent dispersibility of the dye precursor and the electron-accepting compound and excellent rewriting durability can be obtained, a double bond is particularly introduced into the molecule of the thermoplastic resin, Radiation (light irradiation such as visible light, ultraviolet light, γ-ray, and electron beam, cobalt beam,
A resin which is curable by irradiation with a particle beam such as a heavy particle beam) is preferable. For example, a resin obtained by ester-polymerizing a vinyl chloride / vinyl acetate / vinyl alcohol copolymer with acrylic acid or methacrylic acid can be used.

The above-mentioned other components include, in addition to the binder resin described above, a reversible thermosensitive recording layer mainly containing an electron-donating compound (leuco dye) and an electron-accepting compound (color-reducing agent). , If necessary, further a dispersant,
A surfactant such as a fluorine-based surfactant, a conductive agent, a filler, a lubricant such as silicone, an antioxidant, a light stabilizer, an ultraviolet absorber, a color stabilizer, a decolorization accelerator, and the like can be appropriately used.

In a reversible thermosensitive recording material, rapid cooling following heating may be performed to develop color, and cooling speed after heating may be reduced to perform decoloring. For example, when heating with a suitable heat source thermal head, laser light, heat roll, heat stamp, high frequency heating, radiant heat from an electric heater, hot air, etc. for a relatively long time, not only the reversible thermosensitive recording layer but also the support etc. are heated. As a result, the cooling rate is reduced, and a phase separation state (decoloring state) occurs. On the other hand, after heating by an appropriate method such as the above-mentioned heating means or the like, a rapid cooling is performed by pressing a low-temperature metal block or the like against the heated portion, so that a colored state can be developed.

As described above, when heating is performed for a very short time using a thermal head, laser light, or the like, cooling (solidification) starts immediately after the completion of heating, so that a colored state can be developed. Therefore, the same heating temperature and / or
Alternatively, even if the same heat source is used, the color-developed state and the decolored state can be arbitrarily expressed by controlling the cooling rate. When a thermal head is used, the voltage applied to the thermal head, the width and interval of the energizing pulse, etc. are appropriately adjusted, the amount of applied heat is adjusted to change the temperature gradient, and the temperature is gradually cooled or rapidly cooled. Such decoloring or coloring can be performed.

The reversible thermosensitive recording material according to the present invention is a material that can use a thermal head as a heat source, and can be overwritten by a thermal head. This means that the reversible thermosensitive material according to the present invention is no less inferior to those conventionally known, or has a higher response speed in printing / erasing than conventional products.

[Reversible Thermosensitive Recording Medium] Next, the reversible thermosensitive recording medium according to the present invention will be described. A reversible thermosensitive recording medium according to the present invention has the reversible thermosensitive recording material described above. Such a reversible thermosensitive recording medium preferably has a reversible thermosensitive recording material as described above on a substrate as described below. In particular, a reversible thermosensitive recording material can be provided on a substrate, and a protective layer or the like for protecting the reversible thermosensitive recording material can be provided as appropriate. In addition, a reversible thermosensitive recording layer containing a reversible thermosensitive recording material is formed directly or via a layer such as an anchor layer on a base material, or a reversible thermosensitive recording material containing a reversible thermosensitive recording material on a peelable base material is used. An adhesive sheet having a layer and an adhesive layer, formed into a transfer sheet, or having a reversible thermosensitive recording layer containing a reversible thermosensitive recording material on a substrate, and having an adhesive layer on the back surface of the substrate. The transfer sheet or the adhesive sheet may be transferred or adhered to another base material or the like, and may be appropriately laminated.

<Substrate> The substrate is not particularly limited and may be used, for example, paper (including synthetic paper such as nonwoven fabric), resin film (for example, polyester film such as polyethylene phthalate film and polybutylene phthalate film, polyethylene Films, polyolefin films such as polypropylene films, acrylic films, PVC films, fluororesin films, etc.), metal films, glass (including fibrous) and the like. In addition, composites of these and the like are also used. Further, the substrate may be any of the materials described above, and is transparent,
It may be translucent or opaque. The substrate used in the present invention may be in the form of a film other than the above-mentioned materials, and is appropriately selected according to the purpose.

<Protective Layer> In the reversible thermosensitive recording medium according to the present invention, the protective layer may not be provided. In addition, a reversible thermosensitive recording medium is manufactured for the purpose of performing erasing and / or writing a plurality of times by directly contacting the reversible thermosensitive recording medium using a heating applying means such as a thermal head as a heating applying means. In such a case, a protective layer is preferably provided. The protective layer is not particularly limited as long as it is usually used as a protective layer.
In the present invention, it can be composed of an ultraviolet curable resin,
The protective layer may contain silica or the like, and further, if necessary, further include a dispersant, a surfactant such as a fluorine-based compound, a conductive agent, a filler, a lubricant such as silicone, and an antioxidant. , Light stabilizer, ultraviolet absorber, color stabilizer,
It may contain a decoloring accelerator or the like.

<Other Recording Layer> In the present invention, another recording layer may be provided as necessary. Such a recording layer can be formed using a material capable of recording information electrically, magnetically, or optically. For example, a recording medium such as an electronic chip, a magnetic recording medium, a magneto-optical recording medium, and other heat-sensitive recording media that cause a change such as transparent opacity can be given. The layer can be provided on the same surface as the surface on which the recording layer is provided, or on at least a part of the surface opposite to the surface described above.

The reversible thermosensitive recording medium according to the present invention requires less applied energy at the time of printing and erasing.

[0090] [Example] Hereinafter, further detailed by the present invention through examples, but the present invention is not to be construed as being limited to these examples. First, R in the general formula [1]
₁ is CH ₃ (CH ₂ ) ₂₀ , Ar is a phenyl group, R ₂ is (CH ₂ ) ₂ , X is COO, Y is
Is CONHNHCO and R ₃ is (CH ₂ ) ₂₀ CH ₃
The novel compound represented by the following formula [15] will be described.

[0091]

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<New Compound> (1) 3.4 g of behenic acid [16] in 50 ml of benzene
(10 mmol) was added to the suspension in a nitrogen atmosphere.
Heated to 0 ° C. to dissolve the behenic acid. To this solution, 2 g (15 mmol) of oxalyl chloride [17] was slowly dropped, and the mixture was stirred for 1 hour after the drop. After the completion of the reaction, the pressure was reduced by an aspirator through a cooled 5% aqueous sodium hydroxide solution trap, and the pressure was heated to 60 ° C., and the solvent was distilled off until no distillate was produced, thereby removing benzene and residual oxalyl chloride. Behenic acid chloride [18] was obtained.

[0093]

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(2) A flask equipped with a mechanical stirrer was charged with 100 ml of N, N-dimethylacetamide and N- [3
-(4-hydroxyphenyl) propiono], N'-n
A suspension containing 5 g (10 mmol) of docosahydrazide [19] and 2 g (20 mmol) of triethylamine was heated to 60 ° C. in a nitrogen atmosphere to completely dissolve [18]. A solution obtained by adding 50 ml of benzene to the reaction solution prepared in the above (1) was slowly dropped into this solution, and a white solid was precipitated. After completion of the dropwise addition, the reaction solution stirred at 60 ° C. for 1 hour was poured onto a Buchner funnel, and the precipitate was subjected to hot filtration under reduced pressure, and washed with water until the furnace solution became neutral. 2 g (yield 50%, mp 137-13)
8 ° C.).

[0095]

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<Reversible Thermosensitive Recording Medium> Next, the reversible thermosensitive recording medium will be described.

[0097] (Example 1). Formation of a reversible thermosensitive recording layer A resin for forming a reversible thermosensitive recording material having a composition ratio shown below,
After adding 2 mmφ zirconia beads and dispersing with a paint shaker for 1 hour to adjust, apply on a 188 μm thick white PET (polyethylene terephthalate) substrate with a wire bar, and dry at 80 ° C. for 5 minutes, A reversible thermosensitive recording layer having a dry film thickness of 6 μm was formed.

Resin leuco dye for forming a reversible thermosensitive recording material (3-diethylamino-6-methyl-7-anilinofluoran; ODB, trade name, manufactured by Yamamoto Kasei Co., Ltd.) 20 parts by weight [3- (4-hydroxyphenyl) propiono], N'-n-docosahydrazide, compound represented by the following formula [19] 59.4 parts by weight Additive (compound represented by the following formula [15]) 6 parts by weight Resin (thermoplastic acrylic resin; trade name BR-80, manufactured by Mitsubishi Plastics, Inc.) 80 parts by weight Solvent (toluene) 640 parts by weight

[0099]

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[0100] 2. Formation of Protective Layer On the entire surface on which the above-mentioned reversible thermosensitive recording layer is formed, a UV-curable acrylic paint as a resin for forming a protective layer (C3-374 (manufactured by Dainippon Ink and Chemicals, Inc.) 75%)) with a wire bar, dried at 80 ° C. for 1 minute, and dried under an ultraviolet irradiation lamp of 160 W / cm for 30 minutes.
Irradiation in a single pass at a speed of m / sec.
Was formed to form a reversible thermosensitive recording medium.

(Example 2) In Example 1, the color-reducing agent of the resin for forming a reversible thermosensitive recording material was changed to 58.5 parts by weight.
A reversible thermosensitive recording medium was produced in the same manner as in Example 1 except that the amount of the additive was changed to 1.5 parts by weight.

Example 3 A reversible thermosensitive recording material was prepared in the same manner as in Example 1 except that the developer for forming the reversible thermosensitive recording material was 57 parts by weight and the additive was 3 parts by weight. A thermal recording medium was produced.

(Example 4) In Example 1, the resin for forming the reversible thermosensitive recording material was changed to 55.5 parts by weight of the developer.
A reversible thermosensitive recording medium was produced in the same manner as in Example 1, except that the amount of the additive was changed to 4.5 parts by weight.

Example 5 A reversible thermosensitive recording material was prepared in the same manner as in Example 1 except that the developer for the reversible thermosensitive recording material was changed to 54 parts by weight and the additive was 6 parts by weight. A thermal recording medium was produced.

(Example 6) In Example 1, the resin for forming the reversible thermosensitive recording material was changed to 52.5 parts by weight of the developer and sensitizer.
A reversible thermosensitive recording medium was produced in the same manner as in Example 1 except that the amount of the additive was changed to 7.5 parts by weight.

Example 7 A reversible thermosensitive recording material was prepared in the same manner as in Example 1 except that the developer for forming the reversible thermosensitive recording material was 51 parts by weight and the additive was 9 parts by weight. A thermal recording medium was produced.

Example 8 A reversible thermosensitive recording medium was prepared in the same manner as in Example 1, except that the developer for forming the reversible thermosensitive recording material was changed to 42 parts by weight and the additive was 18 parts by weight. A thermal recording medium was produced.

Example 9 A reversible photothermographic material was prepared in the same manner as in Example 1 except that the developer for the reversible thermosensitive recording material was changed to 30 parts by weight and the additive was 30 parts by weight. A thermal recording medium was produced.

Comparative Example 1 In Example 1, the additive (N- [3- (4-hydroxyphenyl) propiono]) represented by the formula [19] was used without adding the additive represented by the formula [15]. , N'-n-docosahydrazide) in the same manner as in Example 1 except that the amount was 60 parts by weight. The obtained reversible thermosensitive recording medium can be printed / erased by a thermal head and can be overwritten.

(Comparative Example 2) The same procedure as in Example 1 was carried out except that the sensitizing agent represented by the formula [19] was not added, and the additive represented by the formula [15] was changed to 60 parts by weight. However, no reversible thermosensitive recording medium capable of printing / erasing by a thermal head was obtained.

(Test Method) Using the reversible thermosensitive recording media prepared in Examples 1 to 9 and Comparative Example 1, printing and erasing were evaluated by the following methods. The density used in the evaluation was measured using an optical reflection densitometer RD918 (using a visual filter) manufactured by Macbeth.

1. Printing and erasing conditions Printing conditions: Using a thermal head (8 dots / mm)
The test was performed at 0.7 mJ / dot. Erasing conditions: Using a thermal head (8 dots / mm)
The measurement was performed at 0.5 mJ / dot. Table 1 shows the evaluation results. 2. Heat Resistance Test 1 Heat resistance test 1 was conducted by printing a reversible thermosensitive recording medium at 90 ° C.
After immersion in hot water for 10 seconds and cooling at room temperature, the print density remaining on the medium was measured. Table 1 shows the results.

3. Heat resistance test 2 Information was printed on the reversible thermosensitive recording media obtained in Example 3 and Comparative example 1, and a hot plate at a temperature shown in Table 2 was applied thereto at 1 kg / cm ² for 3 seconds. Crimping was performed and the concentration was measured. Table 2 shows the results.

4. Time-dependent change of erasing energy range Further, with respect to the reversible thermosensitive recording media obtained in Example 3 and Comparative Example 1, the erasing energy range of information printed at the time of producing the reversible thermosensitive recording medium was changed to And examined after standing at room temperature for one month from the production. The results are shown in Table 3 and FIG.

[0115]

[Table 1]

[0116]

[Table 2]

[0117]

[Table 3]

(Evaluation) As shown in Table 1, the reversible thermosensitive recording media of Examples 1 to 9 containing the novel compound represented by the above formula [15] in the reversible thermosensitive recording material had the background density and erasure. The difference from the concentration was 0.1 or less, indicating that the medium had good erasability almost equivalent to that of the (conventional) reversible thermosensitive recording medium of Comparative Example 1 not containing this novel compound. That is, it was found that the reversible thermosensitive recording medium (material) in which the novel additive was contained in a range of more than 0% by weight and 50% by weight or less with respect to the color-reducing agent had a good erasing density.

Further, the novel compound was added to
In the reversible thermosensitive recording medium contained in the range of more than t% and 30 wt% or less, the difference between the print density and the background density was 0.65 or more, and it was found that the information was easy to confirm visually. Above all, the reversible thermosensitive recording medium contained in an amount not exceeding 15 wt% showed a difference between the print density and the background density of 0.80 or more, indicating that the print medium had particularly good printability.

In the reversible thermosensitive recording medium of Comparative Example 1 which did not contain the above novel compound, the difference between the print density and the background density of the information remaining after the heat resistance test 1 was 0.01, and the information was visually observed. It was found that the difference was 0.05 or more in the reversible thermosensitive recording medium containing the above-mentioned novel compound, making it possible to visually confirm the information. Above all, in a reversible thermosensitive recording medium containing the novel compound in an amount of 2.5% by weight or more based on the developer, the difference was 0.10 or more, indicating that the recording medium had particularly good heat resistance.

Further, from Table 1, when the above-mentioned novel compound is contained in the range of more than 0% by weight and 15% by weight or less with respect to the color-reducing agent, as the content increases, the print density remaining after the heat resistance test 1 and It was found that the difference from the background density increased.

In the heat resistance test 2 taking the example 3 as an example,
As shown in Table 2, it was found that the erasing temperature was higher than that of the conventional reversible thermosensitive recording medium (Example 1). Therefore, it is considered that the heat resistance of the reversible thermosensitive recording medium was improved by adding the novel compound to the reversible thermosensitive recording material.

Further, as shown in Table 3 and FIG. 1, the printing energy range and the erasing energy range of the thermal head were the same as those of the reversible thermosensitive recording medium of Example 3 containing the novel compound and the conventional reversible thermosensitive recording medium. It was found that there was no change with the recording medium (Comparative Example 1). That is, it was found that even when the above-mentioned novel compound was contained, it had the same overwrite characteristics as the conventional reversible thermosensitive recording medium.

Further, as shown in Table 3, the erasing energy range (initial erasing energy range) at the time of producing the reversible thermosensitive recording medium was the erasing energy range after leaving at room temperature for one month (erasing energy over time (one month)). range)
Also did not change. That is, it was found that even when the novel compound was contained, the print erasing density did not change similarly to the conventional reversible thermosensitive recording medium, and the print erasing characteristics hardly deteriorated with time.

From these results, it was found that the reversible thermosensitive recording medium containing the novel compound in an amount of more than 0% by weight with respect to the color-reducing agent has good heat resistance and erasability. This evaluation is indicated by a circle in the evaluation column of Table 1. A reversible thermosensitive recording medium containing 2.5% by weight or more of the above-mentioned novel compound with respect to the color-developing agent has particularly good heat resistance. It was found to have a concentration. This evaluation is indicated by ◎ in the column of evaluation in Table 1.

[0126]

As apparent from the above description, the compounds represented by the general formulas [1] and [2] are:
It is a novel compound, and it is possible to provide a reversible thermosensitive recording material (medium) containing these compounds with the same good rewrite characteristics as before and also high heat resistance.

Further, these compounds make it possible to provide the reversible thermosensitive recording material (medium) containing these compounds with the same aging stability of print / erase characteristics as in the prior art.

[Brief description of the drawings]

FIG. 1 is a diagram showing the relationship between the color density and temperature of a reversible thermosensitive recording medium.

FIG. 2 shows an erasing energy range and a printing energy range of Example 3 and Comparative Example 1.

[Explanation of symbols]

 T1, T2 temperature

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroyuki Morinaka 4- 14-12 Koishikawa, Bunkyo-ku, Tokyo Joint printing company (72) Inventor Mabi Nakanishi 4- 14-12 Koishikawa, Bunkyo-ku, Tokyo Joint Inside Printing Co., Ltd. (72) Inventor Haruhiko Osawa 4-14-12 Koishikawa, Bunkyo-ku, Tokyo Joint printing Co., Ltd. F-term (reference) 2H026 AA09 BB02 BB24 DD12 DD45 DD53 4H006 AA01 AA03 AB76

Claims (5)

[Claims] 1. A novel compound represented by the following general formula [1]. R ₁ -X-Ar-R ₂ -YR ₃ [1] (In the general formula [1], R ₁ and R ₃ are
Represents an organic group having 1 or more carbon atoms, each of which may be the same or different, and the R ₂ group is a linear or branched alkylene group which may have a substituent; A divalent organic group selected from a group having 1 or more carbon atoms including a divalent hydrocarbon group, a divalent aromatic ring that forms a ring independently of a naphthol ring, and the like, wherein the group is aromatic When forming a ring, a hetero ring may be formed;
The group and the Y group are any divalent group of oxygen atom, sulfur atom, ester, thiourea, urea, thioamide, amide, diacylamine, diacylhydrazine, and oxalic acid diamide. The Ar group may be any of a phenyl group, a naphthyl group, and a biphenyl group. ) 2. A novel compound represented by the following general formula [2]. R ₁ —X—Ar—Y—R ₃ [2] (In the general formula [2], R ₁ and R ₃ are
Represents an organic group having 1 or more carbon atoms, which may be the same or different, and each of the X group and the Y group is an oxygen atom, a sulfur atom, an ester, a thiourea, a urea, a thioamide, an amide, a diacylamine, a diacylhydrazine , Oxalic acid diamide, which may be the same or different, and the Ar group is a phenyl group, a naphthyl group, or a biphenyl group. ) 3. A reversible thermosensitive recording medium comprising the novel compound according to claim 1 or 2, an electron-donating compound, and an electron-accepting compound. 4. The reversible thermosensitive recording medium according to claim 3, wherein the novel compound contains 2.5 to 15% by weight of the electron accepting compound. 5. A reversible thermosensitive recording medium comprising at least a reversible thermosensitive recording layer provided on a substrate, wherein the reversible thermosensitive recording layer is a reversible thermosensitive recording material according to claim 3 or 4. A reversible thermosensitive recording medium, comprising: