JPH10330350A - 2-propanol derivative and recording material using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject derivative capable of providing a recording material which can impart high oil resistance and high plasticizer resistance to colored images produced on the recording material and has high surface whiteness even under high humidity atmosphere by reducing the content of an organic solvent in a 2-propanol derivative. SOLUTION: This derivative is a 2-propanol derivative of the formula whose content of an organic solvent is <=5 wt.%. Such derivative is obtained by a process consisting of an operation e.g. to melt a 2-propanol derivative which has been produced by a known method and contains the organic solvent in an amount larger than 5 wt.% and remove a solvent from it, under reduced pressure, an operation to solidify the derivative after cooling, etc. This derivative can be used in recording materials on which a color-developing dye is used, for example, thermal recording paper or carbonless paper. For example, it is preferable that this derivative is used in an amount of 0.1-5 pts.wt. when used as an image preservation stabilizer, and in an amount of 1-10 pts.wt. when used as a developer or a sensitizer, each based on 1 pts.wt. of the color developing dye.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a 2-propanol derivative having high storage stability of a color image and high whiteness in an uncolored portion, and a recording material containing the derivative.

[0002]

2. Description of the Related Art A recording material utilizing color development by a reaction between a color-forming dye and a developer can be recorded in a short time by a relatively simple apparatus without performing complicated processing such as development and fixing. It is widely used as thermal recording paper for output recording of printers or pressure-sensitive copying paper for forms for copying several sheets simultaneously.

[0003] As these recording materials, those which rapidly develop color, retain the whiteness of the uncolored portion (hereinafter referred to as "background"), and have high color image and background fastness are demanded. . Furthermore, in recent years, it has been used in a large amount in fields where the reliability of recorded images such as labels has been emphasized, and has been applied to plasticizers and fats and oils contained in organic polymer materials used for packaging. There has been a strong demand for recording materials having color images having high storage stability. For this purpose, various problems have been studied, including the development of various auxiliaries such as storage stabilizers, as well as color-forming dyes and developers, but no satisfactory solution has yet been found.

The compound having the structure of the formula (I) in the present invention is disclosed in Japanese Patent Application Laid-Open No. Hei 4-269971, and a color developer for recording materials which is excellent in oil resistance and plasticizer resistance of a color image is provided. Although it is a stabilizer, the whiteness of the background could not be sufficiently maintained. That is, JP-A-4-2697
The recording material using the 2-propanol derivative having the structure of the formula (I) disclosed in Japanese Patent Publication No. 91 has a serious drawback that a background portion develops color in a high-humidity atmosphere and causes significant stains.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to improve the disadvantages of the 2-propanol derivative having the structure of the formula (I) disclosed in Japanese Patent Application Laid-Open No. Hei 4-269971, and to provide an oil-resistant color image. It is an object of the present invention to provide a recording material having a high whiteness of the background even under high humidity and high humidity atmosphere.

[0006]

Means for Solving the Problems As a result of intensive studies for solving the above problems, the present inventors have found that the whiteness of the background of a recording material using a 2-propanol derivative represented by the formula (I) is By using a 2-propanol derivative represented by the formula (I), which strongly depends on the content of the organic solvent in the 2-propanol derivative and the content of the organic solvent is 5% by weight or less, the plasticizer resistance of a color image is improved. Further, they have found that it is possible to provide a recording material having a high oil resistance and a high whiteness of the background even in a high humidity atmosphere, and thus completed the present invention.

That is, according to the present invention, the content of the organic solvent is 5
The present invention relates to a 2-propanol derivative represented by the formula (I) having a weight percent or less. Formula (I)

Embedded image The present invention also relates to a recording material using a color-forming dye, wherein the recording material contains a 2-propanol derivative represented by the formula (I) having an organic solvent content of 5% by weight or less. Furthermore, 2 represented by the formula (I) having an organic solvent content of 5% by weight or less.
-A developing agent in a recording material using a chromogenic dye characterized by comprising a propanol derivative, and a 2-propanol derivative represented by the formula (I) having an organic solvent content of 5% by weight or less. The present invention relates to an image storage stabilizer in a recording material using a chromogenic dye characterized by the following.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The 2-propanol derivative having the structure of formula (I) disclosed in the above-mentioned JP-A-4-269791 forms an adduct with chloroform which is a recrystallization solvent in the course of synthesis. It was isolated as an adduct crystal containing chloroform in an amount of 5 weight percent (0.5 with respect to the 2-propanol derivative 1 of the present invention in a molar ratio). Although the agent has a high property, the whiteness of the background is inferior, and there is a drawback that the background is significantly stained particularly in a high humidity atmosphere.

The 2-propanol derivative represented by the formula (I) is very liable to form an adduct with an organic solvent. In addition to chloroform, a general-purpose organic solvent such as ketones such as acetone in the course of synthesis or purification. , Ethyl acetate, esters such as butyl acetate, alcohols such as isopropanol, and ether solvents such as tetrahydrofuran and 1,4-dioxane easily form adducts with these, and the content of the organic solvent is 5 The content becomes larger than the weight percent, and the recording material using the same has a significantly soiled background under a high humidity atmosphere.

The organic solvent such as chloroform and the 2-propanol derivative represented by the formula (I) form an adduct at a molar ratio of 0.5 to 1: 1 and the adduct is Due to their stable presence, the 2-propanol derivatives of the formula (I) are obtained as adduct crystals containing more than 5% by weight of organic solvents under ordinary conditions of synthesis, purification and drying.

On the other hand, the recording material using the 2-propanol derivative of the present invention in which the content of the organic solvent is reduced to 5% by weight or less by any method has a high plasticizer resistance of a color image. Further, the high whiteness of the background is maintained even in a high-humidity atmosphere, and thus it is possible to obtain a desired recording material having excellent image storability and background storability. Further, the 2-propanol derivative of the present invention forms a stable adduct (hydrate) with water, but this hydrate does not adversely affect the background even in a high humidity atmosphere, and does not contain an organic solvent. It can be used similarly to the 2-propanol derivative of the invention.

The 2-propanol derivative represented by the formula (I) can be synthesized according to the method disclosed in Japanese Patent Application Laid-Open No. Hei 4-269971, but as described above, this compound contains an organic solvent containing more than 5% by weight. It is a body crystal. When such an undesired organic solvent is contained in an amount of 5% by weight or more, it is melted under reduced pressure to remove the solvent, and solidified after cooling, or an organic solvent alone or a mixed system of an organic solvent and water (a preferable organic solvent). As MIBK, C ₁₁
The content of the organic solvent of the present invention can be reduced by lowering the content of the organic solvent by performing an operation such as heating with the above hydrocarbons and the like, but not necessarily limited thereto. Up to 5 weight percent of the 2-propanol derivative can be obtained.

The 2-propanol derivative of the present invention having an organic solvent content of not more than 5% by weight may have a different crystal form or form an amorphous state which is not crystalline depending on the conditions of its formation. This can be confirmed by measurement of an X-ray diffraction pattern, differential scanning calorimetry (DSC), or the like. The derivative of the present invention can be used in any application as long as it is a recording material using a color forming dye, for example, thermal recording paper or pressure-sensitive copying paper.

When the 2-propanol derivative of the present invention is used for heat-sensitive recording paper, it may be carried out in the same manner as in the use of a known image storage stabilizer, color developer or sensitizer. It can be produced by applying a dispersion of a derivative and a color-forming dye in an aqueous solution of a water-soluble binder to a support such as paper and drying. Of course, as described above, it may be contained in the color-forming layer. However, when it has a multilayer structure, it may be contained in any layer such as a protective layer.

When used as an image storage stabilizer, the ratio of the derivative of the present invention to the color forming dye is 0.1 to 5 parts by weight, preferably 0.1 part by weight per 1 part by weight of the color forming dye.
2 to 2 parts by weight, and when used as a color developer or a sensitizer, 1 to 1 part by weight with respect to 1 part by weight of the color forming dye.
The amount is 0 parts by weight, preferably 1.5 to 5 parts by weight.
In the above dispersion, further developer, other image stabilizer, other sensitizer, filler, dispersant, antioxidant, desensitizer,
An anti-adhesion agent, an antifoaming agent, a light stabilizer, a fluorescent whitening agent and the like can be contained as required.

Examples of the chromogenic dye used in the recording material of the present invention include leuco dyes such as fluoran dyes, phthalide dyes, lactam dyes, triphenylmethane dyes, phenothiazine dyes and spiropyran dyes. The dye is not limited, and any color-forming dye can be used as long as it is a color-forming dye that develops color when brought into contact with a developer that is an acidic substance.
Among these dyes, fluoran-based dyes include, for example, 3-diethylamino-6-methyl-7-anilinofluoran, 3-dibutylamino-6-methyl-7-anilinofluoran, and 3- (N -Ethyl-N-isobutylamino) -6-methyl-7-anilinofluorane, 3-
(N-methyl-N-propylamino) -6-methyl-7
-Anilinofluoran, 3- (N-ethyl-N-isopentylamino) -6-methyl-7-anilinofluoran, 3-diethylamino-7- (o-chloroanilino)
Fluoran, 3-dibutylamino-7- (o-chloroanilino) fluoran, 3-diethylamino-7-benzylaminofluoran, 3-diethylamino-5-methyl-7-dibenzylaminofluoran, 3- (N-ethyl- p-Toluidino) -6-methyl-7-anilinofluoran, 3- (N-cyclohexyl-N-methylamino)
-6-Methyl-7-anilinofluorane, 3- (N-ethyl-N-isobutylamino) -5,6-benzofluorane, 3-pyrrolidino-6-methyl-7-anilinofluorane, 3- Piperidino-6-methyl-7-anilinofluoran; 2,4-dimethyl-6-[(4-dimethylamino) anilino] fluoran; CVL;

When the 2-propanol derivative of the present invention is used as an image preservation stabilizer or when used in combination with another color developer, the color developer of the heat-sensitive recording paper is optional, but is representative. Examples thereof include bisphenol A, 4,4′-sec-butylidene bisphenol, 4,4′-cyclohexylidene bisphenol, 2,2′-dihydroxydiphenyl, pentamethylene-bis (4-hydroxybenzoate), etc. Bisphenol compounds such as 1,7-di (4-hydroxyphenylthio) -3,5-dioxaheptane; benzyl 4-hydroxybenzoate;
-Ethyl hydroxybenzoate, propyl 4-hydroxybenzoate, isopropyl 4-hydroxybenzoate, 4-
Butyl hydroxybenzoate, isobutyl 4-hydroxybenzoate, chlorobenzyl 4-hydroxybenzoate, 4
4-hydroxybenzoic esters such as methylbenzyl-hydroxybenzoate and diphenylmethyl 4-hydroxybenzoate; metal salts of benzoic acid such as zinc benzoate and zinc 4-nitrobenzoate; 4-hydroxy-4′-methyldiphenyl Hydroxydiphenylsulfones such as sulfone, 4-hydroxy-4'-isopropoxydiphenylsulfone, 4-hydroxy-4'-butoxydiphenylsulfone, dimethyl 4-hydroxyphthalate, dicyclohexyl 4-hydroxyphthalate, 4-hydroxyphthalic acid 4-hydroxyphthalic acid diesters such as diphenyl,
Esters of hydroxynaphthoic acid such as 2-hydroxy-6-carboxynaphthalene, hydroxyacetophenone, p-phenylphenol, benzyl 4-hydroxyphenylacetate, p-benzylphenol, hydroquinone-monobenzyl ether, and tribromomethylphenyl sulfone. Tribromomethyl sulfones, various B
PS crosslinkable color developers and the like can be mentioned.

Further, the sensitizer for the thermal recording paper when used in combination with other sensitizers is optional, and representative ones thereof are, for example, higher fatty acid amides,
Benzamide, stearic acid anilide, acetoacetic anilide, thioacetanilide, dibenzyl oxalate, dimethyl phthalate, dibenzyl terephthalate, dibenzyl isophthalate, bis (tert-butylphenol) s,
Diethers of 4,4'-dihydroxydiphenyl sulfone, 1,2-bis (phenoxy) ethane, 1,2-bis (4-methylphenoxy) ethane, 1,2-bis (3
-Methylphenoxy) ethane, 2-naphtholbenzyl ether, diphenylamine, carbazole, 2,3-
Di-m-tolylbutane, 4-benzylbiphenyl, 4,
4'-dimethylbiphenyl, m-terphenyl, di-β
-Naphthyl phenylenediamine etc. can be mentioned.

Further, a filler, a dispersant, a color image stabilizing agent,
Antioxidants, desensitizers, anti-sticking agents and the like can be used. Examples of the filler include clay, talc, kaolin, satin white, titanium oxide, calcium carbonate, magnesium carbonate, barium sulfate, magnesium silicate, and aluminum silicate. As a dispersant,
Sulfosuccinates such as dioctyl sodium sulfosuccinate, sodium dodecylbenzenesulfonate, sodium salt of lauryl alcohol sulfate,
Fatty acid salts and the like can be exemplified. Examples of the color image stabilizer include salicylic acid derivatives, metal salts of oxynaphthoic acid derivatives (particularly zinc salts), and other water-soluble zinc compounds. 2,2'- as an antioxidant
Methylenebis (4-methyl-6-tert-butylphenol), 2,2'-methylenebis (4-ethyl-6-
tert-butylphenol), 4,4′-propylmethylenebis (3-methyl-6-tert-butylphenol), 4,4′-thiobis (2-tert-butyl-)
5-methylphenol) and the like. Examples of the desensitizer include aliphatic higher alcohols, polyethylene glycol, guanidine derivatives and the like.
Stearic acid, zinc stearate,
Examples thereof include calcium stearate, carnauba wax, paraffin wax, and ester wax.

When the 2-propanol derivative of the present invention is used for pressure-sensitive copying paper, it can be produced in the same manner as when a known image storage stabilizer, developer or sensitizer is used.
For example, a color-forming dye microencapsulated by a known method is dispersed with a suitable dispersant, and is applied to paper to prepare a color-forming sheet. Further, the developer dispersion is applied to paper to prepare a developer sheet. In this case, when the derivative of the present invention is used as an image storage stabilizer, it may be used by dispersing it in any dispersion liquid of a color former sheet or a developer sheet. The pressure-sensitive copying paper is manufactured by combining the two sheets thus manufactured. For pressure-sensitive copying paper,
A unit composed of an upper sheet carrying a microcapsule containing an organic solvent solution of a chromogenic dye on the lower surface and a lower sheet carrying a developer on the upper surface and a developer, or the microcapsule and the developer May be so-called self-content paper coated on the same paper surface. Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

[0021]

【Example】

Example 1 [Synthesis example of 2-propanol derivative of the present invention having 0.4% by weight of organic solvent] 68 g of 4-benzyloxy-4'-hydroxydiphenylsulfone and epichlorohydrin 15 were placed in a four-diameter flask.
0 g was added, 1 g of a catalyst (tetrabutylammonium bromide) was added, and the mixture was reacted at 90 ° C. for 6 hours. After the completion of the reaction, epichlorohydrin was recovered under reduced pressure, 500 ml of toluene was added to the residue, and 50 g of a 50% aqueous sodium hydroxide solution was further added. After heating and refluxing for 5 hours, the aqueous layer was separated, washed with hot water (100 ml) twice, the toluene layer was dehydrated by azeotropic dehydration, and the toluene layer was cooled off to give 4-benzyloxy-4′-. Glycidyl diphenyl sulfone 7
0 g was obtained.

In a 4-neck flask, 4-benzyloxy-
70 g of 4'-glycidyl diphenyl sulfone and 50 g of 4-benzyloxy-diphenyl sulfone were added, and DMF was added.
Add 200 ml and 3 ml of triethylamine, and add 130
Heated at ~ 140 ° C for 2 hours. The DMF was distilled off under reduced pressure, 300 ml of methanol was added to the residue, and the precipitated crystal was separated by filtration, and 1,3-bis (4-benzyloxydiphenylsulfone-4′-yloxy) -2-propanol 110
g was obtained (melting point 201-205 ° C.).

Using 27 g of the mixture, 50 ml of concentrated hydrochloric acid and 50 ml of acetic acid were added, and the mixture was heated under reflux for about 5 hours until no insoluble matter was eliminated. The reaction solution is methyl isobutyl ketone 2
It was poured into 00 ml and extracted. After separation and washing with water, the solvent was recovered to obtain a crude product. Purified by recrystallization with 5% methanol / chloroform solvent, 1,3-bis (4-hydroxydiphenylsulfone-4′-yloxy) -2-propanol containing 9.5 weight percent chloroform, melting point 168-170 ° C. 9.5 g of crystals were obtained.

Then, this product was suspended in 50 ml of MIBK and 10 ml of water and heated to dissolve. After separating the aqueous layer, the MIBK layer was heated under reduced pressure to remove MIBK. MIBK was distilled off, and 30 ml of methylene chloride and 30 ml of water were added to the residue obtained as an amorphous type.
After stirring for 4 hours, the obtained crystal (hydrate) was filtered off. 50 ml of methylene chloride containing 5% by volume of methanol
Was added and the mixture was stirred for 5 hours, and the obtained crystals were dried at 100 ° C. under reduced pressure to give a crystal with mp143-7 ° C. The result of thermal analysis [thermogravimetry (TG)] of this product is shown in FIG. As can be seen from FIG.
4 weight percent of 1,3-bis (4-hydroxydiphenylsulfone-4'-yloxy) -2-propanol was obtained.

Example 2 [Synthesis Example of 2-Propanol Derivative of the Present Invention Containing 3.2% by Weight of Organic Solvent] In Example 1, 75 ml of methylene chloride was added to 13 g of the residue obtained as an amorphous type. The mixture was refluxed for 24 hours. A crystalline compound which formed an adduct with methylene chloride during the heating was filtered off and dried under reduced pressure at about 100 ° C.
13 g of 30-2 ° C. was obtained. Thermal analysis [thermogravimetric (TG)] results of this product are shown in Fig. 2 and ¹ HNM
The R spectrum (solvent: DMSO-d ₆ ) is shown in FIG. From FIGS. 2 and 3, it can be seen that this crystal is a crystal containing 3.2% of methylene chloride.

Example 3 [Preparation of Thermal Recording Paper] Dye Dispersion (Solution A) 3-Dibutylamino-6-methyl-7-anilinofluoran 7.0 g Polyvinyl alcohol 15% aqueous solution 41.5 g Calcium carbonate 5 g Pure water 40.0 g Derivative dispersion of the present invention (liquid B) Derivative of the present invention of Example 1 or 2 7.0 g Polyvinyl alcohol 15% aqueous solution 41.5 g Calcium carbonate 11.5 g Pure water 40.0 g

Each mixture of the above compositions was sufficiently ground with a sand grinder to prepare each dispersion of Solution A and Solution B, and mixed at a ratio of 2 parts by weight of Solution B to 1 part by weight of Solution A. To prepare a coating solution (dye: developing agent = 1: 2). This coating solution was applied to white paper using a wire rod (No. 12) and dried, and then calendered to prepare a thermosensitive recording paper.

Example 4 [Test of Storage Characteristics of Thermal Recording Paper] The background portion of the thermal recording paper prepared in Example 3 was heated to a temperature of 50%.
The sample was left for 2 hours in an atmosphere at 80 ° C. and a relative humidity of 80%, and the optical densities before and after the test were measured to examine the moist heat resistance of the background. A thermal paper color tester (TH-PMD type, manufactured by Okura Denki Co., Ltd.) was used to develop a checkerboard pattern with a printing voltage of 22 V and a pulse width of 1.8 msec. After leaving at 8 ° C. for 8 hours, the optical density before and after the test was measured to conduct a plasticizer resistance test. Note that a Macbeth reflection densitometer was used for measuring the optical density. Table 1 summarizes the results of the moist heat resistance test of the background and the results of the plasticizer resistance test of the colored image.

Comparative Example 1 [Test for storage characteristics of heat-sensitive recording paper using 2-propanol derivative containing chloroform in an amount of 9.5% by weight] Example 3 was carried out in the liquid B of Example 3 instead of the 2-propanol derivative of the present invention. In Example 1, the 2-propanol derivative containing 9.5% by weight of chloroform produced in the stage before obtaining the final product (the 2-propanol derivative of the present invention having an organic solvent content of 0.4% by weight) was used. A heat-sensitive recording paper was prepared in the same manner as in Example 3 except that the recording was performed, and a test of the storage characteristics was performed on the heat-sensitive recording paper in the same manner as in Example 4. The test results are shown in Table 1. Note in Figure 4 the thermal analysis of 2-propanol derivatives containing chloroform 9.5 wt% used in Comparative Example 1 [thermogravimetry (TG)] results, also ¹ H NM
The R spectrum (solvent: DMSO-d ₆ ) is shown in FIG. 5, respectively.

Comparative Example 2 [Test of storage characteristics of thermosensitive recording paper using bisphenol A] Same as Example 3 except that bisphenol A was used instead of the 2-propanol derivative of the present invention in solution B of Example 3. A heat-sensitive recording paper was prepared in the above manner, and the heat-sensitive recording paper was tested for storage characteristics in the same manner as in Example 4. The test results are shown in Table 1.

[0031]

[Table 1]

The value of the optical density in Table 1 indicates that the higher the numerical value, the higher the density. That is, the thermosensitive recording paper using the derivatives of Examples 1 and 2 has almost the same and small numerical values before and after the moist heat resistance test of the background, so that the whiteness of the background is maintained even in a high humidity atmosphere, and the color image is obtained. It can be seen that the plasticizer resistance of the image is also excellent because the values are almost the same and large before and after the plasticizer resistance test. On the other hand, in the thermal recording paper using the compound of Comparative Example 1, although the plasticizer resistance of the image is excellent, the numerical value of the background is large after the moist heat resistance test. Has occurred.

Further, the thermal recording paper using the compound of Comparative Example 2 has a good moist-heat resistance of the background, but the plasticizer resistance of the image is remarkably inferior. Further, when the image was immersed in salad oil, the thermal recording paper using the compound of Comparative Example 2 was 1
While the color faded almost completely within a minute and it was difficult to read the image, the images of the thermal recording papers using the derivatives of Examples 1 and 2 showed the same image density even after 24 hours of immersion in the same experiment. It was kept high.

[0034]

As is clear from the above Examples and Comparative Examples, the 2-propanol derivative of the present invention has high storability of a color image, particularly high oil resistance and plasticizer resistance, and is high even in a high humidity atmosphere. It is possible to provide an excellent heat-sensitive recording material capable of maintaining the whiteness of the background.

[Brief description of the drawings]

FIG. 1 is a diagram showing the results of thermal analysis (thermogravimetry (TG)) of a 2-propanol derivative of Example 1 of the present invention.

FIG. 2 is a diagram showing the results of thermal analysis [thermogravimetric measurement (TG)] of the 2-propanol derivative of Example 2 of the present invention.

FIG. 3 shows the 2-propanol derivative of Example 2 of the present invention.
¹ HNMR Spectrum (solvent: DMSO-d ₆₎ shows a.

4 is a view showing a result of a thermal analysis (thermogravimetry (TG)) of a 2-propanol derivative containing 9.5% by weight of chloroform used in Comparative Example 1. FIG.

FIG. 5 ¹ HNM of 2-propanol derivative containing 9.5 weight percent of chloroform used in Comparative Example 1.
R spectrum (solvent: DMSO-d ₆₎ shows a.

Claims (4)

[Claims] 1. A 2-propanol derivative represented by the formula (I) having an organic solvent content of 5% by weight or less. Formula (I) 2. A recording material using a color forming dye, wherein the recording material contains the 2-propanol derivative according to claim 1. 3. A developer in a recording material using a color-forming dye, which comprises the 2-propanol derivative according to claim 1. 4. An image preservation stabilizer for a recording material using a color-forming dye, comprising the 2-propanol derivative according to claim 1.