JPH044316B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to phthalide derivatives that are useful as color-forming substances for use in recording materials such as pressure-sensitive recording sheets, heat-sensitive recording sheets, current-carrying heat-sensitive recording sheets, and photosensitive recording sheets. The present invention relates to a novel phthalide derivative that forms a color image readable by an optical character reader, a method for producing the same, and a heat-sensitive recording material using the derivative.

Conventionally, coloring reactions between colorless or light-colored basic dyes and organic or inorganic electron-accepting substances have been used.
Various methods have been proposed for recording information transmitted through energy media such as pressure, heat, electricity, and light; for example, Kondo, Iwasaki, Journal of Paper and Paper Technology Association, Vol. 30, pp. 411-421. , pp. 463-470 (1976), pressure-sensitive copying sheets, heat-sensitive recording sheets, energized heat-sensitive recording sheets, ultrasonic recording sheets,
A large number of methods have been proposed for application to electron beam recording sheets, electrostatic recording sheets, photosensitive recording sheets, and even photosensitive printing materials, type ribbons, ballpoint pen inks, crayons, stamp inks, etc.

Crystal violet lactone is commonly used as a colorless or light-colored basic dye that develops blue in these recording materials. When this dye comes into contact with an electron-accepting substance, it instantly exhibits a clear blue-purple color, but its fastness to sunlight is extremely poor, so the recorded image (color image) is quickly erased by sunlight's ultraviolet rays. It has the disadvantage of causing In addition, in recent years, with the streamlining of office processes, the number of cases in which recorded images on recording media are read and processed using optical character readers has increased significantly, but recorded images obtained with this dye have a light absorption of 700%.
Since it is not in the infrared region of ~900 nm, it could not be applied to such applications at all.

However, the specific phthalide derivatives of the present invention represented by the following general formula [] [In the formula, R ₁ represents a hydrogen atom or an alkyl group,
R ₂ represents a halogen atom, R ₃ and R ₄ each represent a hydrogen atom, an alkyl group, a benzyl group, a phenyl group, or a p-tolyl group, and R ₃ and R ₄ represent an adjacent nitrogen atom, a pyrrolidine ring, and a piperidine ring, respectively. A ring, a hexamethyleneimino ring or a morpholine ring may be formed. X ₁ and Y ₁ are hydrogen atoms, respectively
Represents an alkyl group or an alkoxyl group, n is 0
Or represents an integer from 1 to 4. ] is a colorless or light-colored compound that exhibits a high-density, vivid color tone of blue-green or green when it comes into contact with an electron-accepting substance, but recorded images obtained using this substance cannot be exposed to sunlight for long periods of time. It has the excellent property of stably maintaining its initial color tone even when exposed to sunlight, and since this recorded image has light absorption in the infrared region of 700 to 900 nm, it can also be processed with an optical character reader. .

Therefore, the phthalide derivative represented by the general formula [] of the present invention having excellent properties as described above can be synthesized mainly by the following representative method. That is, as shown below, a phthalic anhydride derivative represented by the general formula [] and an ethylene derivative represented by the general formula [] are mixed by using a dehydration condensation agent to give a
The phthalide derivative represented by the general formula [] of the present invention can be synthesized by reacting at 200°C for several tens of minutes to several hours.

[In the formula, R ₁ , R ₂ , R ₃ , R ₄ , X ₁ , Y ₁ and n have the above-mentioned meanings. ] Specific examples of the phthalic anhydride derivative represented by the general formula [ ] include the following compounds.

Phthalic anhydride, 3 (or 4)-chlorophthalic anhydride, 4,5-dichlorophthalic anhydride, 3,
4,5,6-tetrachlorophthalic anhydride, 3
(or 4)-bromophthalic anhydride, 4,5-dibromophthalic anhydride, 3,4,5,6-tetrabromophthalic anhydride, etc.

Specific examples of the ethylene derivative represented by the general formula [] include the following compounds.

1,1-bis(4-morpholinophenyl)ethylene, 1,1-bis(2-methyl-4-morpholinophenyl)ethylene, 1,1-bis(2-methoxy-4-morpholinophenyl)ethylene, 1-
(4-morpholinophenyl)-1-(4-dimethylaminophenyl)ethylene, 1-(4-morpholinophenyl))-1-(4-N-ethyl-N-benzylaminophenyl)ethylene, 1 -(4-hexamethyleneiminophenyl)-1-(4-morpholinophenyl)ethylene, 1-(4-pyrrolidinophenyl)-1-(4-morpholinophenyl)ethylene, 1-(4-pyrrolidinophenyl)-1-(4-morpholinophenyl)ethylene, peridinophenyl)-1-(4-
morpholinophenyl)ethylene, 1-(4-morpholinophenyl)-1-(4-N-methyl-N-p
-tolylaminophenyl)ethylene, 1,1-bis(4-morpholinophenyl)-1-propene, etc.

Examples of dehydration condensing agents used in the reaction of phthalic anhydride derivatives and ethylene derivatives in the above method include lower fatty acid anhydrides such as acetic anhydride and propionic anhydride, which also serve as solvents, phosphorus oxychloride, phosphorus trichloride, and sulfuric acid. , inorganic acids such as polyphosphoric acid are preferably used, but various other Friedelkraft catalysts may also be used, and these may be used alone or in combination of two or more types.

The thus obtained phthalide derivative of the present invention represented by the general formula [] is a colorless to light-colored basic dye having excellent properties as described above, and is particularly effective as an electron-accepting substance (hereinafter abbreviated as a color developer). It exhibits extremely excellent effects when used in thermosensitive recording materials that utilize color reaction with

In this heat-sensitive recording material, the phthalide derivatives of the present invention may be used alone or in combination, and if necessary, may be mixed with the following basic dyes. 3,3-bis(p-dimethylaminophenyl)-6-dimethylaminophthalide, 3-(p-dibenzylaminophenyl)-3-(1,2-dimethylindol-3-yl)-7- azaphthalide,
3-(4-diethylamino-2-ethoxyphenyl)-3-(1-ethyl-2-methylindole-
3-yl)-7-azaphthalide, 3,3-bis(1-ethyl-2-methylindol-3-yl)
Triarylmethane lactones such as phthalide, 3
-diethylamino-6-methylfluorane, 3-
Diethylamino-6-methyl-7-chlorofluorane, 3-(N-ethyl-N-p-tolylamino)
-7-methylfluorane, 3-diethylamino-
6-Methyl-7-anilinofluorane, 3-(N
-cyclohexyl-N-methylamino)-6-methyl-7-anilinofluorane, 3-(N-ethyl-N-p-tolylamino)-6-methyl-7-
Anilinofluorane, 3-diethylamino-7-
o-chloroanilinofluorane and other oluoranes, di-β-naphthospiropyran, 3-methyl-
Spiropyrans such as di-β-naphthospiropyran, diphenylmethanes such as 4,4'-bis-dimethylaminobenzhydrylbenzyl ether, 4,4'-bis-dimethylaminophenyl-p-toluenesulfinate, 3,7-bis(dimethylamino)-10-benzoylphenothiazine,
Azines such as 3,7-bis(diethylamino)-10-benzoylphenoxazine, N-butyl-
triarylmethanes such as 3-[bis{4-(N-methylanilino)phenyl}methyl]carbazole;

As mentioned above, the phthalide derivative of the present invention exhibits extremely excellent effects particularly when used in heat-sensitive recording materials.

Examples of the color developer used here include inorganic color developers such as acid clay, activated clay, attapulgite, bentonite, colloidal silica, aluminum silicate, magnesium silicate, zinc silicate, tin silicate, calcined kaolin, and talc. , oxalic acid, maleic acid, tartaric acid, citric acid, succinic acid,
Aliphatic carboxylic acids such as stearic acid, benzoic acid, paratertiary butylbenzoic acid, phthalic acid,
Gallic acid, salicylic acid, 3-isopropylsalicylic acid, 3-phenylsalicylic acid, 3-cyclohexylsalicylic acid, 3,5-di-tertiarybutylsalicylic acid, 3-methyl-5-benzylsalicylic acid, 3-phenyl-5-(α, Aromatic carboxylic acids such as α-dimethylbenzyl)salicylic acid, 3,5-di-(α-methylbenzyl)salicylic acid, 2-hydroxy-1-benzyl-3-naphthoic acid,
4,4'-isopropylidenediphenol, 4,
4'-isopropylidene bis(2-chlorophenol), 4,4'-isopropylidene bis(2,6-
dibromophenol), 4,4'-isopropylidene bis(2,6-dichlorophenol), 4,
4'-isopropylidene bis(2-methylphenol), 4,4'-isopropylidene bis(2,6-
dimethylphenol), 4,4'-isopropylidene bis(2-tertiarybutylphenol), 4,
4'-Secondary-butylidene diphenol, 4,
4'-cyclohexylidene bisphenol, 4,
4'-cyclohexylidene bis(2-methylphenol), 4-tertiarybutylphenol, 4-
Phenylphenol, 4-hydroxydiphenoxide, α-naphthol, β-naphthol, methyl-4-hydroxybenzoate, benzyl-4-
Hydroxybenzoate, 2,2'-thiobis(4,6-dichlorophenol), 4-tertiaryoctylcatechol, 2,2'-methylenebis(4
-chlorophenol), phenolic compounds such as 2,2'-methylenebis(4-methyl-6-tertiarybutylphenol), 2,2'-dihydroxydiphenyl, para-phenylphenol-formalin resin, para- Organic color developers such as phenolic resins such as butylphenol-acetylene resins, and these organic color developers such as zinc, magnesium, aluminum, calcium, titanium, etc.
Examples include salts with polyvalent metals such as manganese, tin, and nickel.

For example, heat-sensitive recording media are disclosed in Japanese Patent Publications No. 44-3680 and No. 44-3680.
No. 27880, No. 45-14039, No. 48-43830, No. 49
-69, No. 49-70, No. 52-20142, etc., there are various forms of the phthalide derivative, and the phthalide derivative of the present invention can be applied to these various forms of heat-sensitive recording materials. By simply using the phthalide derivative of the present invention as a dye, a heat-sensitive recording material exhibiting recorded images having excellent properties as described above can be obtained. Generally, a coating liquid obtained by dispersing the phthalide derivative of the present invention and fine particles of a color developer in a medium in which a binder is dissolved or dispersed is applied to paper, plastic film, synthetic paper, nonwoven fabric sheets, molded articles, etc. The heat-sensitive recording material of the present invention is produced by coating it on a support. The ratio of the basic dye mainly consisting of a phthalide derivative and the color developer used in the recording layer is not particularly limited, but is generally 1 to 50 parts by weight, preferably 4 to 10 parts by weight, per 1 part by weight of the dye. A color developer is used.

In addition, inorganic metal compounds such as oxides, hydroxides, and carbonates of polyvalent metals and inorganic pigments are generally used as color developers for the purpose of improving color development, erasing the surface of the recording layer, and improving writing properties. It can be used in combination with 0.1 to 5 parts by weight, preferably 0.2 to 2 parts by weight, and further contains, for example, a dispersion, an ultraviolet absorber, a thermofusible substance, an antifoaming agent, a fluorescent dye, a colored dye, etc. Various auxiliary agents can be used in combination as necessary.

As mentioned above, the heat-sensitive recording material of the present invention is generally manufactured by applying a coating liquid in which fine particles of a phthalide derivative and a color developer are dispersed to a support, but the phthalide derivative and the color developer are separately separated. It is also possible to coat the support with two types of coating liquids dispersed in the two types of coating liquids, and it is also of course possible to manufacture the coating liquid by impregnation or rolling. There are no particular limitations on the preparation method or coating method of the coating solution, and the coating amount is generally about 2 to 12 g/m ² in terms of dry weight. Examples of binders include starches, celluloses, proteins, gum arabic, porovinyl alcohol, styrene-maleic anhydride copolymer salt, styrene-butadiene copolymer emulsion, and vinyl acetate-maleic anhydride copolymer salt. ,
Polyacrylates and the like are appropriately selected and used.

The present invention will be described in more detail with reference to Examples below, but the present invention is not limited thereto unless it goes beyond the gist of the present invention. Further, parts and % in the examples represent parts by weight and % by weight, respectively, unless otherwise specified.

Example 1 3.3 g of phthalic anhydride and 14.0 g of 1,1-bis(4-morpholinophenyl)ethylene were mixed with 25 g of acetic anhydride.
and reacted at 80°C for 1 hour. After the reaction is complete,
The reaction product was poured into water, neutralized with ammonia aqueous solution to decompose acetic anhydride, and the resulting precipitate was collected by filtration. The obtained solid was dried and then recrystallized with ethanol to obtain 3,3-bis[1,1
-bis(4-morpholinophenyl)ethylene-2
4.3 g of -yl]phthalide was obtained as pale yellow crystals.
This phthalide derivative developed a green-blue color on silica gel.

Example 2 3,4,5,6- instead of 3.3 g of phthalic anhydride
Using 6.3g of tetrachlorophthalic anhydride, further 1,
1-bis(4-morpholinophenyl)ethylene
1-(4-pyrrolidinophenyl)- instead of 14.0g
1-(4-morpholinophenyl)erethin 13.4g
The melting point was determined in the same manner as in Example 1 except that
3,3-bis[1-(4-pyrrolidinophenyl)-1-(4-morpholinophenyl)ethylene-2-yl]-4,5,6,7-tetrachlorophthalene at 235-240℃ 13.9 g of the compound was obtained as pale yellow-green crystals.
This phthalide derivative developed a dark green color on silica gel.

Example 3 6.3 g of 3,4,5,6-tetrachlorophthalic anhydride was used instead of phthalic anhydride, and 1,1-
Bis(4-morpholinophenyl)ethylene 14.0g
1-(4-morpholinophenyl)-1- instead of
(4-dimethylaminophenyl)ethylene 12.3g
The procedure was carried out in the same manner as in Example 1 except that 3,3-bis[1-(4-morpholinophenyl)-1-(4-dimethylaminophenyl)ethylene-2] having a melting point of 280 to 283°C was used. -yl]-4,5,6,7-tetrachlorophthalide as pale yellow crystals 11.7g
Obtained. This phthalide derivative developed a dark green color on silica gel.

Example 4 3,4,5,6- instead of 3.3 g of phthalic anhydride
In the same manner as in Example 1 except that 6.3 g of tetrachlorophthalic anhydride was used, 3,
7.9 g of 3-bis[1,1-bis(4-morpholinophenyl)ethylene-2-yl]-4,5,6,7-tetrachlorophthalide was obtained as pale yellow crystals. This phthalide derivative developed a blue-green color on silica gel.

Example 5 3,3-bis[1-(4-
Morpholinophenyl)-1-(4-dimethylaminophenyl)ethylene-2-yl]-4,5,6,
A thermosensitive recording paper was produced using 7-tetrachlorophthalide in the following manner.

Preparation of Solution A Phthalide derivative of Example 3 5 parts Stearic acid amide 1 part 2% aqueous solution of hydroxyethyl cellulose 25 parts This composition was ground to an average particle size of 2 with a sand grinder.
Grinded down to microns.

Preparation of Solution B 4,4'-isopropylidene diphenol 50 parts Stearamide 10 parts 2% aqueous solution of hydroxyethyl cellulose
Grind 250 parts of this composition with a sand grinder to an average particle size of 2.
Grinded down to microns.

Preparation of C solution: A solution: 62 parts B solution: 31 parts Ultrafine anhydrous silica (trade name Thyroid 244,
(Manufactured by Fuji Davison Chemical Co., Ltd.) 25 parts 20% aqueous solution of styrene-maleic anhydride copolymer salt 175 parts Zinc stearate 5 parts Water 100 parts The above ratios were mixed to prepare a coating liquid.

The resulting coating solution was coated onto a 50 g/m ² base paper so that the dry coating amount was 6 g/m ² to obtain heat-sensitive recording paper. When the obtained recording paper was pressed against a hot plate at 125° C. for 5 seconds at a pressure of 4 kg/cm ² , it developed a dark green color.
In the light absorption spectrum of this colored image, strong absorption was observed over a wide range from 600 to 900 nm. Furthermore, the light absorption rate of this colored image at 830 nm was 89%, and even after being exposed to sunlight for 5 hours, the light absorption rate remained at 87%, indicating excellent light resistance.

Example 6 3,3-bis[1-(4-morpholinophenyl)
-1-(4-dimethylaminophenyl)ethylene-2-yl]-4,5,6,7-tetrachlorophthalide was replaced with 3,3-bis[1-(4 -pyrrolidinophenyl)-1-(4-morpholinophenyl)ethylene-2-yl]-4,5,
A thermosensitive recording paper was obtained in the same manner as in Example 5 except that 6,7-tetrachlorophthalide was used. When the obtained thermosensitive recording paper was colored in the same manner, it developed a black-green color. The light absorption spectrum of this colored image is
It had broad absorption over 610-900 nm.
In addition, the light absorption rate of this colored image at 830 nm is 92
%, and showed a light absorption rate of 89% even after being exposed to sunlight for 5 hours, indicating excellent light resistance.

Comparative Example 1 In preparing liquid A, 3,3-bis[1-(4-
Morpholinophenyl)-1-(4-dimethylaminophenyl)ethylene-2-yl]-4,5,6,
3,3-bis[1,1-bis(4-dimethylaminophenyl)ethylene-2-yl]-4,5,6,7-tetrachlorophthalide was used instead of 7-tetrachlorophthalide. A thermosensitive recording paper was obtained in the same manner as in Example 5 except that When the color was developed in the same manner as in Example 5, the color tone of the developed color image was green, and its absorption spectrum showed broad absorption from 625 to 900 nm. Further, the light absorption rate of this colored image at 830 nm was 89%, but the light absorption rate decreased to 67% after being exposed to sunlight for 5 hours.

Comparative Example 2 In preparing liquid A, 3,3-bis[1-(4-
Morpholinophenyl)-1-(4-dimethylaminophenyl)ethylene-2-yl]-4,5,6,
3,3-bis[1-(4-pyrrolidinophenyl)-1-(4-
dimethylaminophenyl)ethylene-2-yl]
A thermosensitive recording paper was obtained in the same manner as in Example 5 except that -4,5,6,7-tetrachlorophthalide was used. When this thermal recording paper was colored in the same way,
The color tone of the colored image is green, and its absorption spectrum is
It showed broad absorption from 620nm to 900nm. Further, the light absorption rate of this colored image at 830 nm was 91%, but the light absorption rate decreased to 72% after being exposed to sunlight for 5 hours.

Claims (1)

[Claims] 1. A phthalide derivative represented by the following general formula []. [In the formula, R ₁ represents a hydrogen atom or an alkyl group,
R ₂ represents a halogen atom, R ₃ and R ₄ each represent a hydrogen atom, an alkyl group, a benzyl group, a phenyl group, or a p-tolyl group, and R ₃ and R ₄ represent an adjacent nitrogen atom, a pyrrolidine ring, and a piperidine ring, respectively. A ring, a hexamethyleneimino ring or a morpholine ring may be formed. X ₁ and Y ₁ are hydrogen atoms, respectively
Represents an alkyl group or an alkoxyl group, n is 0
Or represents an integer from 1 to 4. ] 2 A phthalic anhydride derivative represented by the following general formula [ ] and [In the formula, R ₂ represents a halogen atom, and n represents 0 or an integer of 1 to 4. ] Consisting of reacting with an ethylene derivative represented by the following general formula [] [In the formula, R ₁ represents a hydrogen atom or an alkyl group,
R ₃ and R ₄ each represent a hydrogen atom, an alkyl group, a benzyl group, a phenyl group or a p-tolyl group,
R ₃ and R ₄ may each form a pyrrolidine ring, piperidine ring, hexamethyleneimino ring or morpholine ring with the adjacent nitrogen atom. X ₁ and Y ₁ each represent a hydrogen atom, an alkyl group or an alkoxyl group. ] A method for producing a phthalide derivative represented by the following general formula []. [In the formula, R ₁ , R ₂ , R ₃ , R ₄ , X ₁ , Y ₁ and n have the above-mentioned meanings. ] 3. A heat-sensitive recording material containing at least one phthalide derivative represented by the following general formula []. [In the formula, R ₁ represents a hydrogen atom or an alkyl group,
R ₂ represents a halogen atom, R ₃ and R ₄ each represent a hydrogen atom, an alkyl group, a benzyl group, a phenyl group, or a p-tolyl group, and R ₃ and R ₄ represent an adjacent nitrogen atom, a pyrrolidine ring, and a piperidine ring, respectively. A ring, a hexamethyleneimino ring or a morpholine ring may be formed. X ₁ and Y ₁ are hydrogen atoms, respectively
Represents an alkyl group or an alkoxyl group, n is 0
Or represents an integer from 1 to 4. ]