JPH0740663A - Heat-sensitive recording material developing color with light - Google Patents

Abstract

PURPOSE:To obtain a recording material which develops color only at a heated part through radiation of light by using a hydrazinolactam compound of a specific structure as an electron-donating compound in a sheet of recording body provided with a layer basically containing the electron-donating compound, an electron-accepting compound and an adhesive on a supporting body. CONSTITUTION:At least one kind of hydrazinolactam compounds represented by the formula is used as an electron-donating compound in a layer basically containing the electron-donating compound, an electron-accepting compound and an adhesive. Accordingly, only a heated part develops color when light is irradiated. In the formula, Z is O or S, Q1 is H or an alkyl group, Q2 is an alkyl group, an aryl group or the like, a ring A is an aryl group or a heterocycle, R1, R2, R5-R7, R9 are substituted amino groups or the like, R8 is an aralkyl group or the like, and R6 and T7 may bond to form a heterocycle and R6 and R7, R7 and R8, R8 and R9 may respectively bond to form a naphthalene ring and a benzene ring, and R3 and R4 indicate an aralkyl group or the like.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heat-sensitive and color-developing recording material in which only a heated portion develops color upon irradiation with light, has excellent storage stability of an image, and has little background fog due to light. Furthermore, since the recorded image cannot be seen as it is after thermal recording with a thermal head, laser light, etc., it can be used as a hidden information recording material because of the characteristic property that it develops color only when irradiated with light.

[0002]

2. Description of the Related Art Generally, in a heat-sensitive recording sheet, an electron-donating compound (color former) and an electron-accepting compound (developing agent) are pulverized into fine particles, and a binder, a sensitivity improver, a filler and other auxiliaries are added. A coating liquid added and mixed is coated on a support, and color recording is obtained by heating with a thermal head, laser light or the like.

These heat-sensitive recording sheets are widely applied to heat-sensitive type facsimiles, printers, POS labels, etc. because they are maintenance-free and easy to miniaturize. However, the stability of the recorded image and the background is not sufficient. In particular, discoloration of recorded images due to light exposure and increase of background fog, and discoloration due to plasticizers and oils are large, and improvement thereof is desired.

[0004]

SUMMARY OF THE INVENTION The present invention solves the problems of the stability of the recorded image and the background, and is also maintenance-free and can be combined with a thermal printer which is widely used because of its compact size. , Providing hidden information recording material.

[0005]

According to the present invention, a layer basically containing an electron-donating compound (color former), an electron-accepting compound (developing agent) and a binder is provided on a support. In the recording sheet, by using at least one hydrazinolactam compound represented by the following general formulas (1), (2), (3), (4) and (5) as an electron donating compound, The above problems are solved all at once.

General formula (1)

(Wherein Z is an oxygen atom or a sulfur atom, Q1 is a hydrogen atom, an alkyl group is Q2 is an alkyl group, a cyclic alkyl group or an aryl group, and a ring A is an aryl group or a heterocyclic group,
R1, R2, R5 to R7 and R9 are each independently a hydrogen atom, a halogen atom, a branched alkyl group, an alkoxy group, a cyclohexyl group or a substituted amino group, and R8 is
Hydrogen atom, halogen atom, optionally branched alkyl group,
It represents an amino group which may have an alkyl group, an aralkyl group or an aryl group as a substituent. R6 and R7 may combine to form a heterocycle, and R6 and R7, R7 and R7
8, R8 and R9 may be connected to each other to form a naphthalene ring together with a benzene ring. R3 and R4 each independently represent a branched alkyl group, a cycloalkyl group, an alkoxyalkyl group, an aryl group, an aralkyl group, an alkenyl group or a tetrahydrofurfuryl group. R3 and R4 may combine to form a morpholino ring, a pyrrolidino ring or a piperidino ring. )

General formula (2)

[Chemical 7] (In the formula, Ar @ 1, Ar @ 2 represents an aryl group, a heterocyclic group, ring A, Q _1, Q ₂ are as defined in formula (1).)

General formula (3)

[Chemical 8] (In the above formula, Ar3 and Ar4 represent an aryl group or a heterocyclic group, and R10, R11, R12 and R13 represent a hydrogen atom, a halogen atom, a branched alkyl group, an alkoxy group or an aryl group, and A, Q ₁ and Q ₂ are the same as defined in the general formula (1).)

General formula (4)

[Chemical 9] (In the above formula, Ar5 and Ar6 represent an aryl group or a heterocyclic group, and R14, R15, R16 and R17 represent a hydrogen atom, a halogen atom, an alkyl group which may be branched, an alkoxy group or an aryl group, j Represents an integer of 0 or 1, and rings A and Q
₁ and Q ₂ are the same as the definition of the general formula (1). )

General formula (5)

[Chemical 10] (In the above formula, R18, R19, R20 and R21 represent a hydrogen atom, an alkyl group and an aryl group, and R22 and R23 represent a hydrogen atom, a halogen atom, an optionally branched alkyl group, an alkoxy group and an aryl group. , M, n represent an integer of 1 to 3,
Rings A, Q ₁ and Q ₂ have the same definitions as in formula (1). )
(Note that general formulas (1), (2), (3), (4), and (5)
The alkyl group, aryl group and heterocycle in are further substituted with an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an alkylthio group, an arylsulfonyl group, a halogen atom, a nitro group, a cyano group, a substituted amino group, a substituted carbamoyl group and a substituted group. It may have a substituent such as an oxycarbonyl group, a substituted oxysulfonyl group and a substituted sulfanoyl group. )

The following compounds may be mentioned as specific examples of the general formula used in the present invention.

Compound 01

[Chemical 11]

Compound 02

[Chemical 12]

Compound 03

[Chemical 13]

Compound 04

[Chemical 14]

Compound 05

[Chemical 15]

Compound 06

[Chemical 16]

Compound 07

[Chemical 17]

Compound 08

[Chemical 18]

Compound 09

[Chemical 19]

Compound 10

[Chemical 20]

Compound 11

[Chemical 21]

Compound 12

[Chemical formula 22]

Compound 13

[Chemical formula 23]

Compound 14

[Chemical formula 24]

Compound 15

[Chemical 25]

Compound 16

[Chemical formula 26]

Compound 17

[Chemical 27]

Compound 18

[Chemical 28]

Compound 19

[Chemical 29]

Compound 20

[Chemical 30]

Of course, the present invention is not limited to these, and if necessary, two or more kinds of compounds can be used in combination.

As the electron-accepting compound (developing agent) used in the present invention, various known compounds can be used, and specific examples include the following.

Salicylic acid, 3-isopropylsalicylic acid, 3,5-di-tert. -Butylsalicylic acid, 3,
5-di-α-methylbenzyl salicylic acid, 2 ′, 4-dihydroxydiphenyl ether, 1,5-bis (3-
Hydroxyphenoxy) pentane, 4,4'-isopropylidene diphenol, 4,4'-isopropylidene bis (2-chlorophenol), 4,4'-isopropylidene bis (2,6-dichlorophenol), 4,4 ′-
Isopropylidene bis (2,6-dimethylphenol), 4,4'-isopropylidene bis (2-ter
t. -Butylphenol), 4,4'-cyclohexylidenebisphenol, 4,4'-cyclohexylidenebis (2-methylphenol), 4-tert. -Butylphenol, 4-phenylphenol, 4-hydroxydiphenoxide, α-naphthol, β-naphthol,
3,5-xylenol, thymol, methyl-bis (4-
Hydroxyphenyl) acetate, n-butyl-bis (4-hydroxyphenyl) acetate, 4,4'-thiodiphenol, bis (4-hydroxy-3-methylphenyl) sulfide, 4,4'-diphenolsulfone, 4 -Isopropoxy-4'-hydroxydiphenylsulfone, 4,4'-dihydroxy-3,3'-diallyldiphenylsulfone, 1,7-di (4-hydroxyphenylthio) -3,5-dioxaheptane, phloroglysin Carboxylic acid, 4-tert. -Octylcatechol, 2,2-methylenebis (4-chlorophenol), 2,2'-methylenebis (4-methyl-6-te)
rt. -Butylphenol), 2,2'-dihydroxydiphenyl, ethyl p-hydroxybenzoate, propyl p-hydroxybenzoate, butyl p-hydroxybenzoate, benzyl p-hydroxybenzoate, p-hydroxybenzyl p-hydroxybenzoate. , P-hydroxybenzoic acid-o-chlorobenzyl, p-hydroxybenzoic acid-p
-Methylbenzyl, p-hydroxybenzoic acid-n-octyl, benzoic acid, zinc salicylate, 1-hydroxy-2
-Naphthoic acid, 2-hydroxy-6-naphthoic acid, 2-
Zinc hydroxy-6-naphthoate, 4-hydroxydiphenyl sulfone, 4-hydroxy-4'-chlorodiphenyl sulfone, 2-hydroxy-p-toluic acid,
3,5-tert. -Zinc butylsalicylate, 3,5-
tert. -Tin butylsalicylate, tartaric acid, oxalic acid,
Maleic acid, citric acid, succinic acid, stearic acid, 4-
Examples include hydroxyphthalic acid, boric acid, thiourea derivatives, and 4-hydroxythiophenol derivatives. In particular, 4-
Diphenyl sulfones such as isopropoxy-4'-hydroxydiphenyl sulfone and 4,4'-dihydroxy-3,3'-diallyl diphenyl sulfone are preferable.

Various known recording sensitivity improvers can be used in the recording layer of the present invention, and specific examples include the following.

Higher fatty acid amide, higher fatty acid ester,
Paraffin wax, 2-benzyloxynaphthalene,
p-benzylbiphenyl, m-terphenyl, 1-hydroxy-2-naphthoic acid phenyl ester, terephthalic acid dibenzyl ester, p-benzyloxybenzoic acid benzyl ester, oxalic acid dibenzyl ester, oxalic acid di-p
-Methylbenzyl ester, 1,2-diphenoxyethane, 1,2-bis (3-methylphenoxy) ethane, benzenesulfonanilide and the like.

In the present invention, α, α, α-tribromomethylphenyl sulfone, 2 ', 2'-bis (2-radical chlorophenyl) -4,4', 5,5'-tetraphenyl-1,1 '. When a radical generator such as -Bi-1H-imidazole is used in combination, the color is developed to a higher concentration by light irradiation.

In addition, kaolin, clay, talc, calcium carbonate, zinc stearate and the like can be added in order to prevent the thermal head from sticking to dust and sticking.

A water-soluble or water-insoluble binder is used as the binder for binding the mixture of the color former and the developer onto the support sheet. Typical examples are polyvinyl alcohol, methyl cellulose, hydroxyethyl cellulose, carboxymethyl cellulose, gum arabic, starch, oxidized starch, gelatin, casein, polyvinylpyrrolidone, styrene-maleic anhydride copolymer, polyacrylic acid amide, poly. Acrylate, terpene resin, petroleum resin and the like can be mentioned.

Next, a specific production example of the heat-sensitive and light-coloring recording sheet of the present invention will be shown. The weight ratio of each of the above-mentioned components in the recording layer at the time of production is 0.5 to 5.0 times, preferably 1.0 to 3 times as much as 1.0 for the color developer.
The sensitivity is 0.5 to 10.0 times, preferably 1.0 to 4.0 times, and the radical generator is 0.1 times.
~ 5.0 times, preferably 0.2 to 2 times, the binder is 0.3
To 3.0 times, preferably 0.5 to 2.0 times.

The color-developing agent and the color-developing agent are preferably separated from each other, and the sensitivity-enhancing agent may be used alone, or may be mixed with either the color-developing agent or the color-developing agent. Then, preferably, water in which the binder is dissolved is dispersed as a medium, dispersed using a disperser such as a ball mill, a dyno mill, a sand mill or a paint conditioner, and pulverized to have 1 to 6 μ, preferably 1 to 3 μ particles. Make a sized suspension. If necessary, a defoaming agent, a dispersant or a bleaching agent may be added to disperse and pulverize.

Next, a suspension for dispersing and pulverizing each of the above components is mixed so that the weight ratio of each component in the recording layer is the above ratio, and a coating material for forming the recording layer. To do. Apply this paint to the wire bar No. 6 to N
o. 20 and the solid weight after drying is 3 to 10 g /
The heat-sensitive material of the present invention can be prepared by coating the surface of paper to m ² and drying in a blast dryer at room temperature to 70 ° C. or less.
Manufacture photochromic recording paper. Inorganic or organic filler to improve running performance of thermal head, if necessary
Further, a radical generator may be added to the coating material to improve the color density.

[0043]

EXAMPLES The present invention will be described in detail below with reference to examples and comparative examples, but the present invention is not limited to these examples. In addition, all "parts" in Examples and Comparative Examples represent parts by weight.

Example 1 The following solutions A, B, C and D were prepared respectively. Liquid A (dye dispersion) Compound of the present invention 01: 8 parts 10% polyvinyl alcohol aqueous solution ...・ ・ ・ 40 copies Water ・ ・ ・ ・ ・ ・ ・ ・ 32 copies

Liquid B (developer dispersion liquid) 4-hydroxy-4′-isopropoxydiphenylsulfone: 6 parts Zinc stearate: ... 3 parts p-benzylbiphenyl ... 4 parts 10% polyvinyl alcohol aqueous solution ...・ 10 copies Water ・ ・ ・ ・ ・ ・ ・ ・ 57 copies

Liquid C (filler dispersion) 30% calcium carbonate dispersion

Solution D (binder solution) 10% polyvinyl alcohol aqueous solution

Liquids A, B and C of the above composition are pulverized with a Dyno-Mill KDL disperser to a particle size of 1 to 3 μm.

Next, the respective liquids are mixed in the following proportions to prepare a heat-sensitive / light-coloring recording paint. Solution A: 4 parts Solution B: 16 parts Solution C: 10 parts Solution D: ... ..8 copies

This mixed paint was A wire bar of 18 was used to apply a dry solid content of 7 g / m ² to the surface of the high-quality paper, which was then placed in a blower drier and dried to prepare a heat-sensitive / light-coloring recording paper.

The heat-sensitive and photo-coloring recording paper thus obtained was treated with a Yuri roll mini-calender so that the smoothness was about 300 seconds, and the dynamic color tester TH-P manufactured by Okura Electric was used.
When a character pattern was printed on the MD, no color was seen at this point, but only the character pattern printed part was colored black by sunlight or fluorescent light irradiation, and recording paper similar to a general word processing document was obtained.

Examples 2 to 7 Thermosensitive / photochromic recording papers were prepared in the same manner as in Example 1 except that the following compounds were used instead of the compound 01 in the liquid A of Example 1. When these recording papers were tested as in Example 1, similar results were obtained. Example 2: Compound 02 Example 3: Compound 03 Example 4: Compound 04 Example 5: Compound 06 Example 6: Compound 07 Example 7: Compound 08

Comparative Example A thermal paper was prepared in the same manner as in Example 1 except that 2-anilino-3-methyl-6-dibutylaminofluorane was used in place of the liquid A of Example 1. On this thermal paper, a black character pattern was obtained at the same time as printing with the color tester. Table 1 collectively shows the results of the storability test of the recorded images of Examples 1 to 7 and Comparative Example.

[0054]

[Table 1]

Examples 8 to 10 Compound 08 was used in place of compound 01 of solution A of Example 1, and the following developer was used in place of 4-hydroxy-4'-isopropoxydiphenylsulfone in solution B. A heat-sensitive / color-developing recording paper was prepared in the same manner as in Example 1 except that it was used, and was tested in the same manner as in Example 1. As a result, a red recorded image free of background fog was obtained. Among them, the developer of Example 8 had a high concentration. Example 8: 4,4'-Hydroxy-3,3'-diallyldiphenylsulfone Example 9: Bisphenol A Example 10: p-Hydroxybenzoic acid benzyl ester

Examples 11 to 13 Compound 06 was used in place of compound 01 in solution A of Example 1, and the following developer was used in place of 4-hydroxy-4'-isopropoxydiphenylsulfone in solution B. A heat-sensitive / color-developing recording paper was prepared in the same manner as in Example 1 except that it was used and tested in the same manner as in Example 1. As a result, a dark green recorded image free of background fog was obtained. Among them, Example 1
The color developer 1 had a high density. Example 11: 4,4'-Hydroxy-3,3'-diallyldiphenylsulfone Example 12: Bisphenol A Example 13: p-Hydroxybenzoic acid benzyl ester

Example 14 By replacing the solution B of Example 8 with the solution B described below, a heat-sensitive / color-developing recording paper was prepared in the same manner as in Example 1, and the same test as in Example 1 was carried out. A red image having a higher density than 8 was obtained. Liquid B 4,4'-Hydroxy-3,3'-diallyldiphenylsulfone ... 6 parts Zinc stearate ... 3 parts p-benzylbiphenyl ... 4 parts α, α, α-tribromomethylphenyl sulfone ...・ 1 part 10% polyvinyl alcohol aqueous solution ・ ・ ・ 10 parts water ・ ・ ・ ・ ・・ ・ ・ ・ ・ ・ ・ ・ 56 copies

[0058]

According to the present invention, as is clear from the results of (Table 1), the preservability of recorded images is excellent, particularly oil resistance and plasticizer resistance. It is a heat-sensitive and light-coloring recording material that can be applied as a hidden information recording material because it has no fog and only the heat-printed part clearly develops color.

[Chemical 6]

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI technical display location 6956-2H B41M 5/18 103 (72) Inventor Hiroko Sato 7 Daikokucho, Tsurumi-ku, Yokohama-shi, Kanagawa No.43 Hodogaya Chemical Co., Ltd.Tsurumi Plant

Claims (1)

[Claims] 1. A layer having an electron-donating compound, an electron-accepting compound and a binder as a basic component, represented by the following general formulas (1), (2), (3) and (3) as an electron-donating compound. 4),
A heat-sensitive / color-developing recording material, characterized in that by using at least one hydrazinolactam compound represented by (5), only the heated part develops color upon irradiation with light. General formula (1) (In the above formula, Z is an oxygen atom, a sulfur atom, Q ₁ is a hydrogen atom, an alkyl group, Q ₂ is an alkyl group, a cyclic alkyl group,
Aryl group, ring A is an aryl group, heterocyclic group is R1,
R2, R5 to R7 and R9 are each independently a hydrogen atom, a halogen atom, a branched alkyl group, an alkoxy group,
A cyclohexyl group and a substituted amino group, R8 represents a hydrogen atom, a halogen atom, an alkyl group which may be branched, and an amino group which may have an alkyl group, an aralkyl group or an aryl group as a substituent. R6 and R7 may combine to form a heterocycle, and R6 and R7, R7 and R8, R8 and R9
May combine with each other to form a naphthalene ring together with a benzene ring. R3 and R4 each independently represent an optionally branched alkyl group, cycloalkyl group, alkoxyalkyl group, aryl group, aralkyl group, alkenyl group or tetrahydrofurfuryl group. R3 and R4 may combine to form a morpholino ring, a pyrrolidino ring or a piperidino ring. ) General formula (2) (In the formula, Ar @ 1, Ar @ 2 represents an aryl group, a heterocyclic group, ring A, Q _1, Q ₂ are as defined in formula (1).) In formula (3) ## STR3 ## (In the above formula, Ar3 and Ar4 represent an aryl group or a heterocyclic group, and R10, R11, R12 and R13 represent a hydrogen atom, a halogen atom, a branched alkyl group, an alkoxy group or an aryl group, and A, Q1 and Q2 are the same as defined in the general formula (1).) General formula (4) (In the above formula, Ar5 and Ar6 represent an aryl group or a heterocyclic group, and R14, R15, R16 and R17 represent a hydrogen atom, a halogen atom, an alkyl group which may be branched, an alkoxy group or an aryl group, j Represents an integer of 0 or 1, and rings A and Q
1 and Q2 are the same as defined in the general formula (1). ) General formula (5) (In the above formula, R18, R19, R20, and R21 represent a hydrogen atom, an optionally branched alkyl group, and an aryl group, and R22, R23,
Represents a hydrogen atom, a halogen atom, a branched alkyl group, an alkoxy group, or an aryl group, and m and n are 1 to 3
And the rings A, Q1 and Q2 are the same as defined in the general formula (1). ) (Note that general formulas (1), (2),
The alkyl group, aryl group, and heterocycle in (3), (4), and (5) further include an alkyl group, an alkoxy group, an aryl group, an aryloxy group, an alkylthio group, an arylsulfonyl group, a halogen atom, a nitro group, and a cyano group. Base,
It may have a substituent such as a substituted amino group, a substituted carbamoyl group, a substituted oxycarbonyl group, a substituted oxysulfonyl group and a substituted sulfanoyl group. )