JP3311528B2 - Reversible thermosensitive recording material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reversible thermosensitive recording material capable of repeatedly performing coloring and erasing by controlling thermal energy.

[0002]

2. Description of the Related Art A thermosensitive recording material generally comprises a support having thereon a thermosensitive recording layer mainly composed of an electron-donating, usually colorless or pale-colored dye precursor and a developer which is an electron-accepting compound. By heating with a thermal head, a hot pen, a laser beam, or the like, the dye precursor and the developer react instantaneously to obtain a recorded image. Japanese Patent Publication No. 43-4160, Japanese Patent Publication No. 45-45 It is disclosed in, for example, Japanese Patent No. 14039.

[0003] Generally, such conventional heat-sensitive recording materials include:
Once an image is formed, it is impossible to erase that portion and return to the state before the image formation. Therefore, when information is further recorded, the only option is to add the portion where the image has not been formed. 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 capable of repeatedly forming and erasing images have been devised to address such problems. For example, Japanese Patent Application Laid-Open No. 54-119377 discloses a reversible thermosensitive recording material.
JP-A-63-39377 and JP-A-63-41186 describe a heat-sensitive recording material composed of a resin base material and low organic molecules dispersed in the resin base material.
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.

[0005] Also, Japanese Patent Application Laid-Open Nos. 50-81157 and 50
In the method described in each publication of JP-A-105555, since the image to be formed changes according to the environmental temperature, the temperature at which the image forming state and the erasing state are maintained is different. Cannot be held for an arbitrary period.

Further, Japanese Patent Application Laid-Open No. Sho 59-120492 discloses a method of maintaining an image forming state and an erasing state by keeping a recording material in a hysteresis temperature range by utilizing a hysteresis characteristic of a coloring component. However, this method has a drawback in that a heating source and a cooling source are required for image formation and erasing, and a temperature region in which an image forming state and an erasing state can be maintained is limited to a hysteresis temperature region. It is still insufficient for use in the temperature environment of everyday life.

On the other hand, JP-A-2-188293,
No. 188294 and International Publication No. WO 90/11898 describe a reversible thermosensitive recording medium comprising a leuco dye as a dye precursor and a color-reducing agent which develops and decolorizes the leuco dye by heating. ing. 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. By controlling heat energy, the coloring action by the acidic group or the decolorizing action by the basic group is performed. Is generated preferentially, and coloring and decoloring are performed. 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. Color cannot be completely done. Therefore, sufficient image contrast cannot be obtained. In addition, since the decoloring action of the basic group also acts on the color-developed portion at room temperature, a phenomenon in which the concentration of the color-developed portion decreases with time cannot be avoided.

JP-A-63-173684 and JP-A-4-247895 disclose reversible thermosensitive recording media comprising a combination of a leuco dye and an ascorbic acid derivative, or a combination of a leuco dye and an organic phosphoric acid compound. Has been described. However, the balance between the coloring density and the erasing density is insufficient, and erasing cannot be performed completely.

As described above, in the prior art, there is a reversible thermosensitive recording material having good image contrast, capable of forming and erasing an image, and capable of maintaining a stable image with time in an environment of daily life. Did not.

The present applicant has found a reversible thermosensitive recording material capable of forming and erasing an image with good contrast and capable of maintaining a stable image over time in an environment of daily life. In Japanese Patent Application Laid-Open No. 6-210954.

The reversible thermosensitive recording material thus obtained can certainly form and erase an image with a good contrast, and can maintain a stable image over time in an environment of daily life. However, with the recent increase in the speed of printing machines such as thermal printers, the shortage of sensitivity has emerged as a new problem when a high-density color developing function with a small amount of heat is required.

[0012]

SUMMARY OF THE INVENTION The present invention provides a high-sensitivity reversible thermosensitive recording material among reversible thermosensitive recording materials having excellent coloring properties and erasability.

[0013]

Means for Solving the Problems As a result of intensive studies, the present inventors have found that at least one surface of a support is usually a colorless or pale-color electron-donating dye precursor, and the dye precursor is colored by heating. It is allowed, in the reversible thermosensitive recording material having a reversible thermosensitive recording layer containing a reheating to bleached reversibly developer this, the reversible thermosensitive recording layer, the aqueous high
Intermediate layer composed mainly of molecular resin and aluminum hydroxide
Overcoat layer consisting of particles and resin, UV curable
Resin or electron beam curable resin as main component, cured
And a top coat layer formed in this order.
And solved this problem.

Furthermore, to between the reversible thermosensitive recording layer and the support may be provided an undercoat layer, in the reversible thermosensitive recording layer, or other layers, the surface the reversible thermosensitive recording layer is provided, Alternatively, a material on which information can be recorded electrically, magnetically, and optically may be included on the opposite surface. 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 further subjected to an adhesive process or the like.

The overcoat layer according to the present invention is formed of a transparent pigment, aluminum hydroxide, and a resin.
When this aluminum hydroxide is contained in the overcoat layer and printing is performed, the density, particularly the density at low energy, that is, the sensitivity increases. Although the cause cannot be clearly explained, aluminum hydroxide is a flat particle and a relatively low-hardness pigment. It is conceivable that the sensitivity increases because the water of crystallization has a heat storage effect. Particularly when the content of aluminum hydroxide is 40 to 80% by weight in terms of a solid content ratio, the improvement of this sensitivity is extremely preferable. Aluminum hydroxide is 40
When the amount is less than 40% by weight, the effect of improving sensitivity is not so large as compared with the case where the amount is 40% by weight or more and 80% by weight or less.
When the ratio exceeds, the ratio of the resin may decrease, and the strength of the overcoat layer may decrease.

The overcoat layer according to the present invention has a remarkable effect when the coating amount is 0.3 to 5.0 g / m ² . If the coating amount is less than 0.3 g / m ^2, it is difficult to obtain a uniform overcoat layer, and it is difficult to obtain the effect. On the other hand, if it exceeds 5.0 g / m ² , the thermal conductivity is reduced, so that it may be difficult to obtain a high color density.

As the resin used in the overcoat layer according to the present invention , any of a water-based resin and a solvent-based resin can be used. Latexes can be preferably used.

[0018] Specific examples of the water-soluble polymer, starches, hydroxyethyl cellulose, methyl cellulose,
Carboxymethyl cellulose, gelatin, casein, polyvinyl alcohol, modified polyvinyl alcohol, sodium polyacrylate, acrylamide / acrylate copolymer, acrylamide / acrylate / methacrylic acid terpolymer, styrene / maleic anhydride Examples thereof include an alkali salt of an acid copolymer and an alkali salt or an ammonium salt of an ethylene / maleic anhydride copolymer. Latexes include polyvinyl acetate, polyurethane, polyacrylate, styrene / butadiene copolymer, acrylonitrile / butadiene copolymer, methyl acrylate / butadiene copolymer, ethylene / vinyl acetate copolymer, ethylene / Vinyl chloride copolymer, polyvinyl chloride, ethylene / vinylidene chloride copolymer, polyvinylidene chloride, and the like, but are not limited thereto. These water-soluble polymers or latexes can be used alone or in combination of two or more. These water-soluble polymers or latexes can also be used as a binder in the reversible thermosensitive recording layer for the purpose of improving the strength of the reversible thermosensitive recording layer according to the present invention. Further, it can also be used for an intermediate layer and an undercoat layer. The water-soluble polymer or latex used for each layer may be the same or different.

If necessary, a crosslinking agent such as an epoxy compound, a urea derivative, or a vinyl compound may be added to the undercoat layer.
A curing agent such as a phosphoric acid type, a sulfonic acid type, a polyamide type, and an amine type can be added.

The reversible color developer used in the present invention includes, for example, those represented by the following general formula 1, but is not limited thereto.

The reversible color developer used in the present invention is not particularly limited as long as it is a compound capable of causing a reversible color change in the dye precursor upon heating. As a result,
An electron-accepting compound represented by the following general formula 1 is preferably used, including a reversible developer comprising a phenolic compound proposed in JP-A-210954.

[0022]

Embedded image

In Formula 1, n represents 1, 2 or 3. m represents 0, 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 two or more hetero atoms, a nitrogen atom-containing aromatic ring represented by A, It represents a divalent group bonded by the above hydrocarbon group, or a divalent group containing an unsaturated bond or an aromatic ring. R represents an aliphatic hydrocarbon group. The total number of the atoms included in X and R excluding the hydrogen atoms and the atoms constituting the aromatic ring is 8 or more.

[0024] Specific examples of the substituents represented by Q are 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 an octyloxy group; and a halogen atom such as fluorine, chlorine, bromine and iodine.

[0025] X is, as examples of the divalent group bonding to an aromatic ring represented by A through a nitrogen atom, -NHCO -, -
NH-, -NHCONH-, -NHCONHNH-,-
N = CH -, - N = N -, - NHSO 2 -, - NHCO
_{(P-C 6 H 4)} NHCO -, - NHCO (p-C 6 H 4) N
HCONH -, - NHCO (p- C 6 H 4) NHCOCO
NH -, - NHCO (p- C 6 H 4) CONH -, - NH
_{CO (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 -, - NH
COCH ₂ (p-C ₆ H ₄ ) NHCONH-, -NHCOC
_{H 2 (p-C 6 H} 4) NHCOCONH -, - NHCOCH
_{2 (p-C 6 H 4} ) CONH -, - NHCOCH 2 (p-C 6
H ₄ ) CONHNHCO-, -NHCOCH ₂ (p-C ₆ H
_{4) CONHNHCONH -, - NHCOCH 2} (p-C 6
H ₄ ) CONHNHCOO-, -NHCOCH ₂ (p-C _{6
H 4) OCONH -, - NHCOCH} 2 (p-C 6 H 4) N
_{HCOO -, - NHCOCH 2 CH 2} (p-C 6 H 4) NH
_{CO -, - NHCOCH 2 CH 2} (p-C 6 H 4) NHCO
_{NH -, - NHCOCH 2 CH 2} (m-C 6 H 4) NHCO
_{O -, - NHCOCH 2 CH 2} (p-C 6 H 4) NHCOC
_{ONH -, - NHCOCH 2 CH 2} (p-C 6 H 4) CON
_{H -, - NHCOCH 2 CH 2} (p-C 6 H 4) CONHN
_{HCO -, - NHCOCH 2 CH 2} (p-C 6 H 4) CON
HNHCONH- and 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. It is interesting that X is -CONH-, -CO
In the case of O- and -S-, either the decoloring property or the image density becomes unsatisfactory.

Examples of the divalent group in which X is two or more hetero atoms include —SO ₂ NH—, —S—S—, and —CON.
HNH -, - CONHNHCO -, - CONHCH 2 C
O -, - CONHNHCOO -, - CONHCH 2 CO
O -, - CONHNHCONH -, - CONHCH 2 C
ONH-, -CONHNHCONHNH-, -CONH
_{CH 2 CONHNH -, - CH 2} NHCONH -, - CH
₂ CH ₂ NHCONH-, -CH ₂ CH ₂ CH ₂ NHCON
_{H -, - CH 2 CH 2} CH 2 NHCONH -, - SCH 2 C
_{ONH -, - SCH 2 CH 2} CONH -, - S (CH 2) 5
_{CONH -, - S (CH 2} ) 10 CONH -, - S (p-C
_{6 H 4) CONH -, -} SCH 2 NHCO -, - SCH 2 C
_{H 2 NHCO -, - S (} CH 2) 6 NHCO -, - S (p-
_{C 6 H 4) NHCO -,} - SCH 2 NHCONH -, - S
_{CH 2 CH 2 NHCONH -, -} S (CH 2) 6 NHCON
H -, - S (p- C 6 H 4) NHCONH -, - S (C
_{H 2) 10 NHCONH -, -} SCH 2 CH 2 NHCOO
_{-, - S (CH 2)} 6 NHCOO -, - S (p-C 6 H 4)
_{NHCOO -, - S (CH 2} ) 6 OCONH -, - S (p
_{-C 6 H 4) OCONH -,} - S (CH 2) 11 OCONH
_{-, - SCH 2 CH 2 CONH} -, - S (CH 2) 5 CON
_{H -, - SCH 2 CH 2} NHCO (p-C 6 H 4) -, - S
_{CH 2 CONHNHCO -, - SCH 2} CH 2 CONHN
_{HCO -, - S (CH 2} ) 6 CONHNHCO -, - S
_{(CH 2) 6 CONHNHCO (p} -C 6 H 4) -, - S
(CH ₂ ) ₁₀ CONHNHCO-, -S (p-C ₆ H ₄ ) C
_{ONHNHCO -, - SCH 2 (p} -C 6 H 4) CONHN
_{HCO -, - SCH 2 CH 2} NHCOCONH -, - SC
_{H 2 CH 2 CH 2 NHCOCONH -} , - S (CH 2) 11 N
HCOCONH -, - S (p- C 6 H 4) NHCOCON
_{H -, - SCH 2 CONHCONH -} , - SCH 2 CH 2
CONHCONH -, - S (p- C 6 H 4) CONHCO
_{NH -, - SCH 2 CH 2} NHCONHCO -, - S (p
_{-C 6 H 4) NHCONHCO -,} - SCH 2 CH 2 CON
_{HNHCONH -, - S (CH 2} ) 10 CONHNHCO
_{NH -, - SCH 2 CH 2} NHNHCONH -, - S (p
_{-C 6 H 4) NHNHCONH -,} - SCH 2 CH 2 NHC
ONHNH -, - S (p- C 6 H 4) NHCONHNH
_{-, - SCH 2 CONHCONHNH -,} - SCH 2 CH
_{2 CONHCONHNH -, - S (CH} 2) 10 CONHC
ONHNH -, - S (p- C 6 H 4) CONHNHCON
H -, - S (p- C 6 H 4) CONHCONHNH -, -
SCH ₂ CONHCONHNHCO-, -SCH ₂ CH _{2
CONHCONHNHCO -, - S (CH 2} ) 10 CON
HCONHNHCO -, - S (p- C 6 H 4) CONHN
HCONHCO -, - S (p- C 6 H 4) CONHCON
_{HNHCO -, - SCH 2 CONH (} CH 2) NHCO
_{-, - SCH 2 CH 2 CONH} (CH 2) NHCO -, -
_{S (p-C 6 H 4} ) CONH (CH 2) NHCO -, - S
_{(CH 2) 10 CONH (CH} 2) NHCO -, - SCH 2
_{CON (CH 2) NHCONH -,} - SCH 2 CH 2 CO
_{N (CH 2) NHCONH -,} - S (CH 2) 10 CONH
_{CONH (CH 2) NHCO -,} - S (p-C 6 H 4) CO
_{NH (CH 2) NHCO -,} - SCH 2 CH 2 NHCON
_{H (CH 2) NHCO -,} - SCH 2 CH 2 NHCOCH 2
CONH -, - S (p- C 6 H 4) NHCONH (CH 2)
NHCO -, - S (p- C 6 H 4) NHCOCH 2 CONH
-And the like. Specific examples of the hetero atom include an oxygen atom, a nitrogen atom, a sulfur atom, a phosphorus atom, a boron atom, a silicon atom, a selenium atom, a fluorine atom, a chlorine atom, a bromine atom, an iodine atom, and a tin atom.

[0027] 2 X is, containing an unsaturated bond or aromatic ring
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
A group in which one or two or more linking groups such as H and -S-S- are combined is exemplified. In this case, as a connecting group, other than -CONH-, -O-, -S-, -COO-, -O
Divalent groups such as CO—, —OCOO, —CO—, and —SO ₂ — are also included.

[0028] X comprises a nitrogen atom, examples of the divalent group linked by an aromatic ring and having 1 or more hydrocarbon group having a carbon represented by _{A, -CH 2 CONH -, - CH} 2 CH 2 CO
_{NH -, - 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) OCONH
_{-, - CH 2 CH 2 CONHCO} -, - (CH 2) 5 CON
_{HCO -, - 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) CONH
_{NHCO -, - CH 2 (p} -C 6 H 4) CONHNHCO
_{-, - CH 2 CH 2 NHCOCONH} -, - CH 2 CH 2 C
H ₂ NHCONH—, — (CH ₂ ) ₁₀ NHCONH
H -, - (p-C 6 H 4) NHCOCONH -, - CH 2 C
_{ONHCONH -, - CH 2 CH 2} CONHCONH-,
_{- (p-C 6 H 4} ) CONHCONH -, - CH 2 CH 2 N
HCONHCO -, - (p-C 6 H 4) NHCONHCO
_{-, - CH 2 CH 2 NHCONHNH} -, - (p-C
_{6 H 4) NHCONHNH -, -} CH 2 CH 2 NHNHCO
NH -, - (p-C 6 H 4) NHNHCONH -, - CH 2
_{CONHNHCONH -, - CH 2 CH 2} CONHNHC
_{ONH -, - (CH 2)} 10 CONHNHCONH -, -
_{(P-C 6 H 4)} NHNHCO -, - CH 2 CONHCH 2
_{NHCO -, - CH 2 CH 2} CONHCH 2 NHCO-,
_{- (CH 2) 10 CONHCH 2} NHCO -, - (p-C 6 H
_{4) CONHCH 2 NHCO -, -} CH 2 CONHCH 2 N
_{HCONH -, - CH 2 CH 2} CONHCH 2 NHCON
_{H -, - (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 NHCO
_{CH 2 CONH -, - (p} -C 6 H 4) NHCOCH 2 CO
NH- 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, henicosyl 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, it is necessary for the decoloring property that the total number of atoms excluding the hydrogen atom and the atoms constituting the aromatic ring among the atoms contained in X and R is 8 or more, especially 14 or more.

Next, specific examples of the reversible developer preferably used in the present invention, the present invention is not limited thereto. 4'-hydroxyheptaneanilide, 4 '
-Hydroxy-3-methyloctaneanilide, 4'-hydroxynonadecaneanilide, 3'-hydroxynonadecaneanilide, 4'-hydroxy-10-octadeceneanilide, 15-cyclohexyl-4'-hydroxypentadecaneanilide, 4'- Hydroxy-5-tetradeceneanilide, 3'-cyclohexyl-4'-hydroxyheptadecaneanilide, 3'-allyl-4'-hydroxypentadecaneanilide, 3'-chloro-4'-hydroxyoctadecananilide, 3'-hydroxydodecane Anilide, 2 ', 4'-dihydroxyheptadecane anilide,

[0031] 4'-hydroxy-4-hexyl-benzanilide, 4'-hydroxy-4-octadecyl-benzanilide, 4'-hydroxy-4-pentadecyl aminocarbonyl benzanilide, 4'-hydroxy-4-hexyl-carbonylamino benz Anilide, 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,

[0032] 4'-hydroxy-3,4-di-octyloxy-benzanilide, 4'-hydroxy-3-octyl-4- (octylthio) benzanilide, 4'-hydroxy-3- (heptadecylthio) -5- pentadecyloxy benz Anilide, 4'-hydroxy-3-heptadecylcarbonylamino-5-dodecylbenzanilide,
4'-hydroxy-3-octadecylaminocarbonyl-5-tetradecylaminocarbonylbenzanilide,
4'-hydroxy-3-octadecylsulfonylamino-5-octadecyloxybenzanilide, 4'-hydroxy-3-heptadecyloxysulfonyl-5-tetradecyloxysulfonylbenzanilide, 4'-hydroxy-3,5-bis ( N-docosylideneamino) benzanilide;

[0033] 4'-hydroxy-4-octadecyl carbonylamino benzanilide, 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, '-Hydroxy-4-nonadecylsulfonylbenzanilide, 3', 4 ', 5'-trihydroxy-4-tetracosylaminosulfonylbenzanilide, 3', 5'-dihydroxy-4-pentacosylaminocarbonylbenz Anilide, 3'-hydroxy-4- (N-dodecylideneamino) benzanilide,
N- [4- (3-hydroxyphenylaminocarbonyl) benzylidene] pentadecylamine;

[0034] N- cyclohexyl-4-hydroxy benzhydrazide, N- cyclohexylmethyl-4-hydroxybenzamide hydrazide, 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,

[0035] 4-hydroxy-4'-dodecyl-benzanilide, N- methyl-4-hydroxy-4'-octadecyl benzanilide, 4-hydroxy-4'-octadecyloxy benzanilide, 4-hydroxy-4'-
(Octadecylthio) benzanilide, 4-hydroxy-4'-hexadecylcarbonylbenzanilide, 4-
Hydroxy-4'-heptadecyloxycarbonyloxybenzanilide, 4-hydroxy-4'-dodecyloxycarbonylbenzanilide, 4-hydroxy-4 '
-Heptadecylcarbonyloxybenzanilide, 4-
Hydroxy-4'-cyclohexylaminobenzanilide, 4-hydroxy-4'-octadecylaminobenzanilide,

[0036] 4-hydroxy-4'-heptadecyl carbonylamino benzanilide, 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,

[0037] 3-hydroxy-4'-dodecyloxybenzanilide, 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,

[0038] 4-(N-octadecylsulfonylamino) phenol, 4-(N-methyl--N- octadecylsulfonylamino) phenol, 4- (N-3- methylhexyl sulfonylamino) 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 -Octadecylaminobenzenesulfoneanilide,

[0039] 4'-hydroxy-4-heptadecyl-carbonyl aminobenzenesulfonic anilide, 4'-hydroxy-4-dodecyl-aminocarbonyl benzene sulfonanilide, 4'-hydroxy-4-dodecyl-sulfonyl benzene sulfonanilide, 4'-hydroxy - 4-octadecyloxysulfonylbenzenesulfonanilide, 4'-hydroxy-4-dodecylsulfonyloxybenzenesulfonanilide, N-dodecylidene-4-
(4-hydroxyphenyl) aminosulfonylaniline, N-4- (4-hydroxyphenylaminosulfonyl) benzylideneoctadecylamine, 4'-hydroxy-4-octyloxycarbonylaminobenzenesulfonanilide, 4'-hydroxy-4-octadecyloxy Carbonylaminobenzenesulfonanilide, 4 '
-Hydroxy-4-octadecylureylenebenzenesulfonanilide,

[0040] N- methyl-4'-hydroxy-3-octadecyl oxybenzene sulfonanilide, 3'-hydroxy-4-dodecylbenzenesulfonic anilide, 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,

[0041] 1- (4-hydroxyphenyl dithio) octadecane, 1- (4-hydroxyphenyl dithio) -
9-octadecene, 1- (2-fluoro-4-hydroxyphenyldithio) octadecane, 1- (2-ethoxy-4-hydroxyphenyldithio) octadecane, 1-
(3-chloro-4-hydroxyphenyldithio) octadecane,

[0042] 4'-hydroxy-4-tetradecyl diphenyl sulfide, 4'-hydroxy-4-octadecyl sulfide, 4'-hydroxy-4-octadecyl carbonylamino sulfide, 4 '
-Hydroxy-4-octadecyloxydiphenyl sulfide, 4'-hydroxy-4-octadecyloxysulfonyldiphenyl sulfide, 4'-hydroxy-4
-Octadecylsulfonylaminodiphenyl sulfide,

[0043] 4'-hydroxy-3,4-di-decyl oxy diphenyl sulfide, 4'-hydroxy-3,4
Dioctadecyloxydiphenyl sulfide, 4- (1
5-cyclohexylpentadecyl) -4'-hydroxydiphenyl sulfide, 4'-hydroxy-4- (5-
Tetradecenyl) diphenyl sulfide,

[0044] 3'-chloro-4'-hydroxy-4-octadecyl sulfide, 3'-hydroxy -
4-dodecyldiphenyl sulfide, 3'-hydroxy-4-octadecyldiphenyl sulfide, 3'-hydroxy-4-dodecyloxycarbonyldiphenyl sulfide,

[0045] 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'-icosyl 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,

[0046] 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'-octadecylurea,
N- (3,4,5-trihydroxyphenyl) -N'-
Trichosyl urea, N- (4-hydroxyphenyl)-
N '-(4-tetradecylphenyl) urea, N- (4-
(Hydroxyphenyl) -N′-hexadecylthiourea,
N- (4-hydroxyphenyl) -N'-octadecylthiourea;

[0047] 4-undecanoylamino-amino-1- (4-hydroxyphenyl-aminocarbonyl) benzene, 4-octadecanoyl-amino-1- (4-hydroxyphenyl-aminocarbonyl) benzene, 4- (octadecyl amino carbonyl) 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,

[0048] N-(4-hydroxyphenyl-methyl) -
N'-n-tetradecyl urea, 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,

[0050] 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;

[0051] 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-hydroxy Phenylthio) 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-octadecyl urea, 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] -n-dodecylcarbamate, Nn-octadecylcarbamic acid- [2 − (P−
Hydroxyphenylthio) ethyl], N- [3- (p-
(Hydroxyphenylthio) propionyl] -NN-octadecanoylamine, N- [2- (p-hydroxyphenylthio) aceto] -N'-n-octadecanohydrazide, N- [3- (p-hydroxy Phenylthio) 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 '-( p-n-octylbenzo) hydrazide, N- [11- (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-Trihydroxyphenylthio) 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- [11- (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] carbazic acid-
n-octadecyl, 4- [2- (p-hydroxyphenylthio) ethyl] -1-n-octadecyl semicarbazide, 1- [2- (p-hydroxyphenylthio) ethyl] -4-n-octadecyl semicarbazide, 1- [P
-(P-hydroxyphenylthio) phenyl] -4-n
-Tetradecylsemicarbazide, 1- [3- (p-hydroxyphenylthio) propionyl] -4-n-octadecylsemicarbazide, 1- [p- (p-hydroxyphenylthio) benzoyl] -4-n-octadecylsemicarbazide, 4 -[2- (p-hydroxyphenylthio) ethyl] -1-n-tetradecanoyl semicarbazide, 4- [p- (p-hydroxyphenylthio) phenyl] -1-n-octadecanoyl semicarbazide, 1-
[2- (p-hydroxyphenylthio) acetamide]
-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] ureido {-1-n-octadecanoylaminomethane, N-
[2- (p-hydroxyphenylthio) ethyl] -N '
-N-octadecylmalonamide,

[0053] N- [2- (p- hydroxyphenyl) ethyl] carbamate -n- octadecyl, N-n-octadecyl carbamate - [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-docosanohydrazide, 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- (p-hydroxyphenyl) benzo] -N'-n-octadecanohydrazide, N
-[P- (p-hydroxyphenylmethyl) benzo]-
N'-n-octadecanohydrazide, N- [3- (p-
Hydroxyphenyl) propyl] -N'-n-octadecyl oxamide, N- [3- (3,4-dihydroxyphenyl) propyl] -N'-n-octadecyl oxamide, N- [p- (p-hydroxyphenyl) ) Phenyl]
-N'-n-octadecyloxamide, N- [2- (p
-Hydroxyphenyl) acetyl] -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,
-[2- (p-hydroxyphenyl) ethyl] -1-n
-Octadecylsemicarbazide, 1- [2- (p-hydroxyphenyl) ethyl] -4-n-tetradecylsemicarbazide, 1- [2- (p-hydroxyphenyl) ethyl] -4-n-octadecylsemicarbazide, 1-
[2- (p-hydroxyphenyl) acetyl] -4-n
-Tetradecylsemicarbazide, 1- [3- (p-hydroxyphenyl) propionyl] -4-n-octadecylsemicarbazide, 1- [11- (p-hydroxyphenyl) undecanoyl] -4-n-decylsemicarbazide, 4- [ 2- (p-hydroxyphenyl) ethyl]-
1-n-octadedecanoyl semicarbazide, 4- [p
-(P-hydroxyphenyl) phenyl] -1-n-octadecanoyl semicarbazide, 1- [2- (p-hydroxyphenyl) acetamido] -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,

[0054] 4-n-octadecyl-aminophenol,
4- (1-octadecynyl) phenol, 4- (1,3
-Octadecadinyl) phenol and the like.

[0055] may be used by mixing one or two or more of these, respectively, the normal colorless or pale colored electron-donating dye precursor, 5 to 5000 wt%, preferably from 10 to 3,000% by weight Used.

The usually colorless or light-colored electron-donating dye precursor used in the present invention is typified by those generally used for pressure-sensitive recording paper and heat-sensitive recording paper, but is not particularly limited. Specific examples include, for example, the following, but the present invention is not limited thereto.

[0057] (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,

[0058] (2) diphenylmethane compounds 4,4'-bis (dimethylaminophenyl) benzhydryl benzyl ether, N- chlorophenyl leucoauramine, N-2,4,5-trichlorophenyl leuco auramine, etc.,

[0059] (3) xanthene compounds Rhodamine B anilinolactam lactam, Rhodamine B-p-chloro-anilino lactam, 3-diethylamino-7-dibenzylamino fluoran, 3-diethylamino-7-octyl amino fluoran, 3- Diethylamino-7-phenylfluoran, 3-diethylamino-7-chlorofluorane, 3-diethylamino-6-chloro-7-methylfluoran, 3-diethylamino-7- (3,4-dichloroanilino) fluoran, 3 -Diethylamino-7
-(2-chloroanilino) fluoran,

[0060] 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-
Anilino fluoran, etc.

[0061] (4) thiazine compounds benzoyl leuco methylene blue, p- nitrobenzoyl leuco methylene blue, etc.,

[0062] (5) Spiro compounds 3-methyl-spiro Gina shift pyran, 3-ethyl-spiro Gina shift pyran, 3,3'-dichloro-spiro Gina shift pyran, 3-benzyl-spiro Gina shift pyran, 3- methylnaphtho - (3 -Methoxybenzo) spiropyran, 3-propylspirobenzopyran and the like.

The above colorless or pale color dye precursors may be used alone or in combination of two or more.

A heat-fusible substance can be contained in the reversible thermosensitive recording layer as an additive for adjusting the color development sensitivity and the decoloring temperature of the reversible thermosensitive recording layer. 60 ° C-20
Those having a melting point of 0 ° C. are preferred, and
Those having a melting point of 0 ° C. are preferred. A sensitizer used in general thermosensitive recording paper can also be used. For example, waxes such as N-hydroxymethyl stearamide, stearamide, palmitamide, etc.
Naphthol derivatives such as 2-benzyloxynaphthalene,
Biphenyl derivatives such as p-benzylbiphenyl and 4-allyloxybiphenyl, 1,2-bis (3-methylphenoxy) ethane, 2,2'-bis (4-methoxyphenoxy) diethyl ether, bis (4-methoxyphenyl) Polyether compounds such as ethers, carbonic acid or oxalic acid diester derivatives such as diphenyl carbonate, dibenzyl oxalate, bis (p-methylbenzyl) oxalate, and the like can be added in combination, but are not limited thereto. is not.

The UV-curable resin or the electron beam-curable resin used in the top coat layer of the present invention includes a compound having an ethylenically unsaturated bond, and more specifically, the following resins.

[0066] (1) an aliphatic, alicyclic, aromatic, polyhydric alcohols and polyalkylene glycols of poly (meth) acrylates of aromatic aliphatic (2) aliphatic, cycloaliphatic, aromatic, araliphatic Poly (meth) acrylate of polyhydric alcohol with alkylene oxide added to polyhydric alcohol (3) Polyester poly (meth) acrylate (4) Polyurethane poly (meth) acrylate (5) Epoxy poly (meth) acrylate (6) Polyamide Poly (meth) acrylate (7) Poly (meth) acryloyloxyalkyl phosphate ester (8) Vinyl- or diene-based compound having (meth) acryloyloxy group at the side chain or terminal (9) Monofunctional (meth) acrylate , Vinylpyrrolidone, (meth) acryloyl compound (10) ethylenically unsaturated (11) Mono- or polycarboxylic acids having an ethylenically unsaturated bond and their alkali metal salts, ammonium salts, amine salts, etc. (12) Ethylenically unsaturated (meth) acrylamide or alkyl-substituted (meth) ) Acrylamide and its multimers (13) Vinyl lactam and polyvinyl lactam compound (14) Polyether having an ethylenically unsaturated bond and its ester (15) Ester of alcohol having an ethylenically unsaturated bond (16) Ethylenic unsaturation (17) Aromatic compound having one or more ethylenically unsaturated bonds such as styrene and divinylbenzene (18) Polyorganosiloxane having a (meth) acryloyloxy group at a side chain or at a terminal Compound (19) Silicone compound having an ethylenically unsaturated bond (20) Multimer or oligoester (meth) acrylate modified compound of the compounds described in (1) to (19) above

[0067] These resins can be used alone, it can be used as a mixture with other resins. Further, it can be applied without a solvent, can be diluted with a solvent and can be applied, or can be applied in an emulsion state, dried and cured.

[0068] The coating amount of the ultraviolet curable resin or electron beam curable resin is thinner for the purpose of avoiding thermal shutdown is desired, 0.5~10.0g / m ² is preferred. If the amount is less than this range, good repetitive usability will not be exhibited, and if it is more than this range, the heat sensitivity will deteriorate.

The reversible thermosensitive recording layer and / or the aqueous polymer intermediate layer and / or the topcoat layer and / or the undercoat layer may contain a pigment. The pigment referred to here is diatomaceous earth, talc, kaolin, calcined kaolin, calcium carbonate, magnesium carbonate, basic magnesium carbonate, titanium oxide, zinc oxide,
Inorganic pigments such as silicon oxide, aluminum hydroxide, calcium silicate, barium sulfate, calcium sulfate, etc., and synthetic or natural materials such as polystyrene resin, polyethylene resin, polypropylene resin, urea-formalin resin, benzoguanamine resin, melamine resin, silicone particles, pine cone, etc. Examples include, but are not limited to, resin powders, corn starch, rice starch, and cereal starches such as wheat starch. These pigments can be used alone or 2
More than one species may be used in combination. In addition, zinc stearate,
Higher fatty acid metal salts such as calcium stearate, paraffin, paraffin oxide, polyethylene, polyethylene oxide, stearic acid amide, waxes such as caster wax, dispersants such as sodium dioctylsulfosuccinate, surfactants, fluorescent dyes, leveling agents, etc. Can also be contained.

In particular, in order to prevent or reduce the occurrence of sticking, it is preferable to contain a pigment in the uppermost layer of the reversible thermosensitive recording medium, and further contain waxes for the purpose of preventing head abrasion and the like.

[0071] Next, described specific method for producing a reversible thermosensitive recording material of the present invention, the present invention is not limited thereto.

As a method for incorporating a colorless or pale-colored dye precursor and a reversible developer into the reversible thermosensitive recording layer,
A method of dissolving or dispersing each compound in water or an organic solvent alone, a method of dissolving or dispersing each compound in water or an organic solvent after mixing each compound, cooling each of the compounds after heating and dissolving them to homogeneity, There is a method of mixing each solution or dispersion obtained by a method of dissolving or dispersing in water or an organic solvent, printing on a support, and coating and drying. In this case, for example, each color-forming component may be contained in a single layer to form a multilayer structure, but the present invention is not particularly limited thereto.

As the support used in the reversible thermosensitive recording material of the present invention, paper, coated paper, various nonwoven fabrics, woven fabric, synthetic resin film, synthetic resin laminated paper, synthetic paper, metal foil, glass, etc. A composite sheet combining these can be used arbitrarily depending on the purpose.
It may be transparent, translucent or opaque,
It is not limited to these. The thickness of the support is not particularly limited as long as it can withstand repeated use, but is 20 to 1300 μm, preferably 40 to 100 μm.
It is about 0 μm.

The method for forming each layer constituting the reversible thermosensitive recording material of the present invention on a support is not particularly limited, and it can be formed by a conventional method. For example,
Air knife coater, blade coater, bar coater, curtain coater, gravure roll and transfer roll coater, roll coater, U comma coater, AKKU coater, smoothing coater, micro gravure coater, reverse roll coater, 4 or 5 roll coater, dip Coating equipment such as coater, rod coater, kiss coater, gate roll coater, squeeze coater, slide coater, die coater, etc., and various printing machines by lithographic, letterpress, intaglio, flexo, gravure, screen, hot melt etc. it can.

At the time of providing these layers, there is no problem in performing a surface treatment such as corona discharge for the purpose of improving adhesiveness.

[0076] Yet another conventional drying process, UV irradiation · E
Each layer can be held by B irradiation. By these methods, smearing and printing can be performed one layer at a time or simultaneously at multiple layers.

In the case where the overcoat layer is cured by the ultraviolet curing method in the present invention, a photoreaction initiator is mixed and used. Examples of photoreaction initiators include acetophenones such as di and trichloroacetophenone, benzophenone, Michler's ketone, benzyl, benzoin, benzoin alkyl ether, benzyl dimethyl ketal, tetramethylthiuram monosulfide, thioxanthones, azo compounds, various silver salts, and the like. The amount of the photoinitiator used is
It is usually in the range of 0.1 to 10% based on the ultraviolet curable resin. In some cases, a storage stabilizer such as hydroquinone is used as the photoinitiator.

[0078] As the ultraviolet irradiation device, for example, low pressure mercury lamp, medium pressure mercury lamps, high pressure mercury lamp, there is a metal halide lamp or the like, there is also a small ozone-less type ozone generator. Generally, a plurality of lamps having an output of 30 w / cm or more are used in parallel.

When the overcoat layer is cured by the electron beam curing method according to the present invention, the electron beam irradiation is performed at an acceleration voltage of 100 to 1000 kV, more preferably 100 to 300 kV, in terms of transmission power and curing power. Using an accelerator,
It is preferable that the absorbed dose in one pass be 0.5 to 20 Mrad. If the acceleration voltage or the amount of electron beam irradiation is lower than this range, the electron beam transmission power is too low to perform sufficient curing, and if it is higher than this range, not only does the energy efficiency deteriorate, but also the resin, Undesirable effects on quality such as decomposition of additives and reduction in strength of base paper appear.

The electron beam accelerator may be, for example, any of an electro-curtain system, a scanning type, a double scanning type and the like.

When irradiating with an electron beam, if the oxygen concentration is high, the curing of the electron beam-curable resin is hindered.
Substitution with an inert gas such as helium or carbon dioxide is performed to reduce the oxygen concentration to 600 ppm or less, preferably 400 p.
Irradiation is preferably performed in an atmosphere suppressed to pm or less.

In the reversible thermosensitive recording material of the present invention, rapid cooling following heating is sufficient to form a color recording image, and the cooling rate after heating is slow to erase the recorded image. Good. 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,
Suitable heat source (thermal head, laser beam, heat roll,
Radiation heat from heat stamps, high frequency heating, electric heaters, and light sources such as tungsten lamps and halogen lamps,
When heating with a hot air or the like for a relatively long time, not only the recording layer but also the support and the like are heated. 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 expressed by controlling the cooling rate.

[0083]

The support contains, on at least one side of the support, a generally colorless or light-colored electron-donating dye precursor, and a reversible developer for causing the color of the dye precursor to develop by heating and then reheating to erase the color. In a reversible thermosensitive recording material provided with a reversible thermosensitive recording layer, by providing an overcoat layer comprising aluminum hydroxide particles and a resin on the reversible thermosensitive recording layer, high sensitivity, that is, high energy at low energy, A reversible thermosensitive recording material having a density of coloring was obtained.

[0084]

The present invention will be described in more detail with reference to the following examples. In the examples, parts and% are based on weight.

[0085] Reference Example 1 (A) is a work made dye precursors reversible thermosensitive coating solution 3-di -n- butylamino-6-methyl-7-Ani Reno fluoran 40 parts of 2.5% polyvinyl alcohol The mixture was ground with a ball mill for 24 hours together with 90 parts of the aqueous solution to obtain a dye precursor dispersion. Then, N- (4-hydroxyphenyl) -N'-n-octadecyl urea 10
0 parts were ground together with 400 parts of a 2.5% aqueous polyvinyl alcohol solution in a ball mill for 24 hours to obtain a dispersion. 2 above
After mixing the seed dispersion, 200 parts of 10% aqueous solution of polyvinyl alcohol, adding 400 parts of water, mixed well and made it creates the reversible heat-sensitive coating liquid.

[0086] (B) a reversible heat-sensitive coating solution on a polyethylene terephthalate (PET) sheet prepared by forming the reversible thermosensitive recording layer (A), solid coating amount 4g / m ²
And dried and then treated with a super calender to form a reversible thermosensitive recording layer.

[0087] On the obtained reversible heat-sensitive recording layer in formation of the (C) overcoat layer (B), 25 parts of a 10% aqueous solution of polyvinyl alcohol, to a solution consisting of 30% aluminum hydroxide dispersion 17 parts of added water , A coating solution of an overcoat layer adjusted to a solid content concentration of 12% was applied so as to have a solid content of 1.0 g / m ² , dried, and then treated with a super calender to obtain a reversible thermosensitive recording material. Obtained.

[0088] Other forming the intermediate layer in the following manner between the reversible thermosensitive recording layer and the overcoat layer of the reversible thermosensitive recording material of Reference Example 2 Reference Example 1, in the same manner as in Reference Example 1, sensitive reversibly A thermal recording material was obtained. (Formation of Intermediate Layer) On the reversible thermosensitive recording layer, an intermediate layer coating solution composed of polyvinyl alcohol was applied so as to have a solid content of 0.8 g / m ² , dried, and then treated with a super calender. To form an intermediate layer.

[0089] On the overcoat layer of the reversible thermosensitive recording material of Example 1 Reference Example 2, as a topcoat layer, Aronix M8030
(Toa Gosei Chemical Industry Co., Ltd. product) 85 parts, N-vinyl-
Top coat layer consisting of 5 parts of 2-pyrrolidone, 5 parts of Irgacure 500 (product of Nippon Ciba Geigy Co., Ltd.), 5 parts of Mizukasil P527 (product of Mizusawa Chemical Co., Ltd.), and 5 parts of Escalon 100 (product of Sankyo Flour Milling Co., Ltd.) after the coating solution was coated so as to sufficiently stirred 1.5 g / m ^2, an ultraviolet irradiation device (Ushio Co., Rapid cure) except that was cured at in the same manner as in reference example 1, A reversible thermosensitive recording material was obtained.

[0090] The overcoat layer coating solution of Comparative Example 1 Reference Example 1, except that no provided, in the same manner as in Reference Example 1 to obtain a reversible heat-sensitive recording material.

[0091] The overcoat layer coating solution of Comparative Example 2-3 Reference Example 1, except that was changed to the following composition, in the same manner as in Reference Example 1 to obtain a reversible heat-sensitive recording material. (Comparative Example 2) 25% aqueous solution of 10% polyvinyl alcohol
Part, 30% light calcium carbonate dispersion liquid, 17 parts of added water, and an overcoat layer coating liquid prepared to a solid concentration of 12% by adding water (Comparative Example 3) 10% aqueous solution of polyvinyl alcohol 25
Parts, 17% of a 30% silica dispersion, and water added thereto to prepare an overcoat layer coating liquid having a solid content concentration of 12%.

[0092] Test 1 (color density) Reference Example 1-2, a reversible thermosensitive recording material obtained in Example 1 and Comparative Examples 1 to 3, Kyocera print head KJT-256-
Using a thermal facsimile printing tester TH-PMD manufactured by Okura Electric with 8MGF1, printing was performed under the conditions of an applied pulse of 1.0 millisecond and an applied voltage of 26 volts, and the density of the obtained color image was measured using a densitometer Macbeth RD918. It was measured. The results are shown in Table 1.

Test 2 ( Erasability of Image) The color-developed reversible thermosensitive recording material obtained in Test 1 was treated with about 1
After passing through a heat roller (MS Pouch manufactured by Meiko Shokai) heated to 20 ° C., the concentration was measured in the same manner as in Test 1.
The results are shown in Table 1.

[0094]

[Table 1]

[0095] Image density of Example 1 1. Although the density was as high as 37, the printed images of Reference Examples 1 and 2 and Comparative Examples 1 to 3 were all low, and it was clear that the sensitivity was lower than that of Examples.

[0096] Reference Example 1 using an aqueous polymer resin in the overcoat layer has a higher image density than the reference example 2 using an ultraviolet curable resin, an aqueous polymer resin overcoat sensitive reversible thermosensitive recording material It turned out to be more preferable. Reference Example 2 , in which an intermediate layer mainly composed of an aqueous polymer resin was provided between the overcoat layer of the reversible thermosensitive recording material and the reversible thermosensitive recording layer, had a higher image density than Reference Example 1 without the intermediate layer. Example 1 in which a layer made of an ultraviolet-curable resin was provided on the overcoat layer, and Reference Example 1 in which a corresponding layer made of an ultraviolet-curable resin was not provided,
It was found that the image density was higher than that of Sample No. 2 and the sensitivity was high.

[0097]

According to the present invention, at least one surface of a support is usually provided with a colorless or pale-colored electron-donating dye precursor, and a reversible developer for causing the color of the dye precursor to develop by heating and then reheating to decolorize the precursor. In a reversible thermosensitive recording material provided with a reversible thermosensitive recording layer, an aqueous polymer is provided on the reversible thermosensitive recording layer.
Intermediate layer composed mainly of resin and aluminum hydroxide particles
And an overcoat layer made of resin and an ultraviolet curable resin
Or a top coat layer mainly composed of an electron beam curable resin
Are provided in this order to obtain a reversible thermosensitive recording material having high sensitivity, that is, low energy and high density coloring.

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-6-270541 (JP, A) JP-A-5-32050 (JP, A) JP-A-6-344673 (JP, A) JP-A-6-344673 270545 (JP, A) JP-A-6-155906 (JP, A) JP-A-7-117351 (JP, A) JP-A-5-124360 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) B41M 5/28-5/34

Claims (1)

(57) [Claims] 1. A colorless, usually colorless, surface on at least one side of a support.
A light-colored electron-donating dye precursor, and the dye
A reversible microscope that develops the color of the precursor and reheats it to erase the color
Reversible thermosensitive layer provided with reversible thermosensitive recording layer containing colorant
In the recording material, the aqueous reversible thermosensitive recording layer
Intermediate layer mainly composed of resin and aluminum hydroxide particles
Overcoat layer made of resin and resin, and UV curable resin
Resin or electron beam curable resin
And a top coat layer consisting of
Reversible thermosensitive recording material.