JPS58183755A - Fluoran derivative, preparation thereof and recording material prepared by using it - Google Patents

Abstract

NEW MATERIAL:A compound of formula I (R1 and R2 are 1-12C alkyl or 7- 9C aralkyl; X is H, halogen or 1-4C alkyl or 1-2C alkoxyl; Y is H, halogen or 1-4C alkyl). EXAMPLE:3-Diethylamino-7-(o-biphenyl)aminofluoran. USE:A color developing material used in recording materials, e.g. pressure-, heat-, electric heat- and photosensitive recording sheets. PROCESS:An m-aminophenol derivative of formula II is reacted with phthalic anhydride to synthesize a 2-(2-hydroxy-4-amino)benzoylbenzoic acid of formula III, which is then condensed with a biphenylaminophenol derivative of formula IV.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a fluoran derivative useful as a color-forming substance used in recording materials such as pressure-sensitive recording sheets, heat-sensitive recording sheets, current-carrying heat-sensitive recording sheets, and photosensitive recording sheets, a method for producing the same, and derivatives thereof. The present invention relates to a recording medium using.

Conventionally, there has been no method to record information transmitted through energy media such as pressure, heat, electricity, or light, using a color reaction between a colorless or light-colored basic dye and an organic or inorganic electron-accepting substance. Various methods have been proposed; for example, Chikakatsu, Shunga, Paperback Technical Association Magazine 30S, pp. 411-421, 46
Pressure-sensitive recording sheets, heat-sensitive recording sheets, electrically conductive heat-sensitive recording sheets, such as those described on pages 3 to 470 (1976);
A large number of methods have been proposed for application to ultrasonic recording sheets, electron beam recording notebooks, electrostatic recording sheets, photosensitive recording sheets, and even photosensitive printing materials, type ribbons, ballpoint pen inks, crayons, stamp inks, etc. There is.

For these recording materials that utilize a color reaction between an electron-donating color-forming substance (hereinafter simply referred to as a color-forming agent) and an electron-accepting color-developing substance (hereinafter simply referred to as a color-forming agent), the type of color-forming agent must be selected. Colored images exhibiting various hues are formed by these methods, but in recent years, there has been a strong demand for recording materials that can produce black colored images for the purpose of making further copies of the obtained colored images. In this case, in principle, a black colored image is obtained by mixing color formers that develop colors of different hues such as red, blue, yellow, and green, but there is a drawback that the image cannot maintain its color tone. Therefore, research has been carried out to obtain black colored images using a single coloring agent, but the stability of the coloring agent before coloring, coloring speed, coloring density, fastness, etc.
A black color former that satisfies all aspects such as hue and cost has not yet been found, and as a result, black color recording materials have not always been satisfactory.

However, the fluoran derivative of the present invention represented by the following general formula (1) [wherein R, , , Rj each represents a C/ to C/2 alkyl group or a C3 to Cq aralkyl group, and X represents water 1A
WX child, halogen atom, alkyl group of CI''C4 or C
1 to Ct alkoxyl group, Y represents a water S atom, a halogen atom, or a C/Ct alkyl group.] is a colorless to light-colored stable compound that turns reddish-black to black when it comes in contact with a color developer. It develops a highly concentrated hue, and the recorded images obtained using this material have the property of stably maintaining the initial color tone even when exposed to sunlight, and when applied to thermal recording paper, for example. □ In this case, a recorded image with less background fog and excellent color development can be obtained.

The fluoran derivative represented by the general formula (1) of the present invention having excellent properties as described above can be produced mainly by the following representative method. That is, as shown below, first m-aminophenol derivative (IV
) and phthalic anhydride (V) to synthesize 2-(2-hydroxy-4-amino)benzoylbenzoic acid (II).

I RJ (R,, R2 have the above-mentioned meanings) By condensing the obtained 2-(2-hydroxy-4-amino)benzoylbenzoic acid [■] with the biphenylaminophenol derivative (1), the general formula Fluoran derivatives represented by (+) can be produced.

[In the formula, Rr represents a hydrogen atom or a Ct-C2 alkyl group, and R7, R2, X, and Y have the above-mentioned meanings. ] 2-(2-hydroxy-4-amino)benzoylbenzoic acid [1] and biphenylaminophenol derivative ([11
) as a condensing agent in the condensation reaction with sulfuric acid; phosphorus pentoxide; phosphoric acid; polyphosphoric acid; anhydrous tin chloride, anhydrous zinc chloride, anhydrous aluminum chloride, anhydrous tin bromide, anhydrous tin chloride, anhydrous aluminum bromide, Friedel-Crafts catalysts such as anhydrous metal halides such as anhydrous iron; phosphorus trichloride; phosphorus tribromide; phosphorus pentachloride; phosphorus pentabromide; anhydrous boron trifluoride; used. Among these, sulfuric acid which also serves as a solvent is more preferably used. Examples of solvents include carbon disulfide, monochlorobenzene, dichlorobenzene, trichlorobenzene, nitrobene, nitromethane, and nitroethane. In addition, in the above reaction, when Rj of the biphenylaminophenol derivative is a C7-c2 alkyl group, the following general formula [
(2) A triphenylmethane derivative represented by [2] may be synthesized.

[In the formula, Rt s R2, RJ, and Xs Y have the above-mentioned meanings. ] In this case, the obtained triphenylmethane derivative is separated in a furnace as necessary, and the P'l of the system is adjusted to 9°5-12 with an alkaline substance such as sodium hydroxide or potassium hydroxide, and heated to 50-100°C. The desired fluoran derivative can be obtained by heating. Note that the yield can be effectively increased if an organic solvent such as a7tone, benzene, toluene, or xylene is used in combination with the above aqueous medium. Hydrophobic organic solvents such as benzene, toluene, and xylene are more preferably used because they prevent the formation of side reactions and provide preferable reaction conditions.

The thus obtained fluorinated orchid derivative represented by the general formula (1) of the present invention is a colorless to light-colored basic dye having excellent properties as described above, and in particular, it can be dyed using a color reaction with a color developer. It exhibits extremely excellent effects when used in various types of recording media.

The color developer used here is appropriately selected depending on the type of recording medium, but the fluoran derivative and the color developer are brought into contact with each other through pressure, heat, or electrical energy.
For example, substances that act as Brønsted or Lewis acids are preferably used in recording bodies such as pressure-sensitive recording bodies, heat-sensitive recording bodies, electrically conductive heat-sensitive recording bodies, ultrasonic recording bodies, electrostatic recording bodies, tie-liphones, ballpoint pen inks, and crayons. . Specifically, examples include acid clay, activated clay, attapulgide, bentonite, colloidal clay, aluminum silicate, magnesium silicate, silica #1 curved lead, soot silicate, calcined kaolin, inorganic color developers such as talc, oxalic acid, maleic acid, etc. acids, aliphatic carboxylic acids such as tartaric acid, citric acid, succinic acid, stearic acid, benzoic acid, para-tertiary butylbenzoic acid, phthalic acid, gallic acid, salicylic acid, 3-isopropylsalicylic acid, 3-phenylsalicylic acid, 3-cyclo Hequinrusalicylic acid, 3.5-di-tert-butylsalicylic acid, 3-methyl-5-benzylsalicylic acid, 3
- Aromatic carboxylic acids such as phenyl-5-(α,α-dimethylhensyl)salicylic acid, 3.5-di(α-methylbenzyl)salicylic acid, 2-hydroxy-1-hennor-3-naphthoic acid, 4.4 '-Isopropylidene diphenol, 4.4'-isopropylidene bis(2-chlorophenol), 4.4'-isopropylidene bis(2-chlorophenol)
, 6-dibromophenol), 4.4'-isopropylidene bis(2,6-dichlorophenol), 4.4'-
Isopropylidene bis(2-methylphenol), 4.
4'-isopropylidene hiss (2,6-dimethylphenol), 4,4'-impropylidene bis (2-tert-butylphenol), 4,4'-secondary butylidene diphenol, 4,4'-cyclo hexylidene bisphenol, 4,4'-cyclohexylidene bis(2
-methylphenol), 4-tert-butylphenol, 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), 2.
Phenolic compounds such as 2'--methylenebis (4-methyl-6-ternyabutylphenol), 2,2'-dihydroxydiphenyl, phenolic resins such as hala-phenylphenol-formalin resin, and hala-butylphenol-acetylene resin. Furthermore, organic color developers such as zinc, magnesium,
aluminum, calcium, titanium, manganese, tin,
Salts with polyvalent metals such as nickel, and inorganic acids such as hydrogen chloride, hydrogen bromide, hydrogen iodide, boric acid, silicic acid, phosphoric acid, sulfuric acid, nitric acid, persalt am, and aluminum, zinc,
Examples include halides such as nickel, tin, titanium, and boron.

In addition, in the case of electron beam recording materials and photosensitive recording materials, hydrogen halides such as hydrogen chloride, hydrogen bromide, hydrogen iodide, carboxylic acids, sulfonic acids, phenols, etc. are generated by electron beams or light. Carbon bromide, α, α, α-tribromoacetophenone, hexachloroethane, iodoform,
Preferably used are organic halogen compounds such as 2-tribromomethylpyridine and trichloromethylsulfonylbenzene, 0-quinonediazide compounds, and phenol esters of carboxylic or sulfonic acids that cause photo-Pr1es rearrangement.

Regarding various typical recording materials using such a color developer and the fluoran derivative represented by the general formula (1) of the present invention,
This will be explained in more detail below.

Pressure-sensitive recording bodies are disclosed in, for example, U.S. Pat.
No. 505471, No. 2505489, No. 254836
No. 6, No. 2712507, No. 2730456, No. 2
No. 730457, No. 3418250, No. 392402
As described in No. 7 and No. 4010038, there are various types of fluorane derivatives, and the fluoran derivative of the present invention can be applied to these various types of pressure-sensitive recording media.

Generally, the fluoran derivatives of the present invention are used alone or in combination, and if necessary, triphenylmethane lactones,
Spiropyrans, fluorans, diphenylmethanes,
Along with basic dyes such as leucomethylene blue, synthetic oils such as alkylated naphthalene, alkylated diphenyl, alkylated diphenylmethane, and alkylated terphenyl, vegetable oils such as cotton oil and castor oil, animal oils, mineral oils, or mixtures thereof, etc. A dispersion solution prepared by dissolving the dispersion in a solvent consisting of a The pressure-sensitive recording material of the present invention is produced by applying the dispersion dispersed therein onto a support such as paper, plastic sheet, resin-coated paper, or the like.

Of course, it is possible to use a so-called glazing sheet in which one side of the support is coated with the above dispersion, and a so-called sheet in which one side of the support is coated with a color developer coating liquid mainly containing a color developer, and the other side is coated with the above dispersion. By applying a coating liquid containing a mixture of the capsules and color developer on the same side of the middle circumferential sheet and furthermore on the support, or by applying a developer coating liquid on top of the capsule dispersion liquid, As described above, the present invention includes various forms such as a so-called stand-alone copying sheet in which the above-mentioned capsule and color developer coexist. The amount of fluoran derivative used varies depending on various conditions such as the desired coating amount, the form of the pressure-sensitive recording medium, the capsule manufacturing method, the composition of the coating liquid including each additive, and the coating method. and select as appropriate. In any case, by using the fluoran derivative represented by the general formula (1) of the present invention as a basic dye in various conventional pressure-sensitive recording materials, it is possible to form recorded images with excellent light resistance. It's what the body gets.

For example, heat-sensitive recording materials are disclosed in Japanese Patent Publication Nos. 44-3680 and 44-3680.
No. 27880, 45. -14039, same 48-4
No. 3830, No. 49-69, No. 49-70, No. 52
-20142, etc., and the fluorane derivative of the present invention can be applied to these various types of heat-sensitive recording materials, and moreover, the fluorane derivative of the present invention,! As mentioned above, a heat-sensitive recording material exhibiting a recorded image having excellent properties can be obtained by using only the four dyes as dyes. Generally, a coating liquid obtained by dispersing fine particles of the fluoran derivative of the present invention and a color developer in a medium in which a binder is dissolved or dispersed is used for paper, plasti, Kufilm, synthetic paper, woven fabric sheets, molded articles, etc. The heat-sensitive recording material of the present invention is produced by coating on a suitable support. The ratio of the basic dye mainly consisting of a fluoran derivative and the color developer used in the recording layer is not particularly limited, but is generally 1 to 50 parts by weight, preferably 2 to IO 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, matting the surface of the recording layer, and improving writing properties.
0.1 to 5 parts by weight, preferably 0.2 to 2 parts by weight
Parts by weight can be used in combination, and various aids such as dispersants, ultraviolet absorbers, thermofusible substances, antifoaming agents, fluorescent dyes, and coloring dyes 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 fluoran derivative and a color developer are dispersed to a support, but the fluoran derivative and the color developer are each dispersed separately. Of course, it is also possible to coat the two types of coating liquids on the support in layers, or to manufacture the coating by impregnation or rolling. There are no particular limitations on the preparation method or coating method of the coating liquid, and the coating amount is generally 2 to 12 g/rr in terms of dry weight. It is applied to a certain extent. Examples of the binder include starches, cellulose, proteins, gum arabic, polyvinyl alcohol, styrene-maleic anhydride copolymer salt,
Styrene-butadiene copolymer emulsicone, acetic acid bee-maleic anhydride copolymer salt, polyacrylate, etc. are appropriately selected and used.

The electrically conductive heat-sensitive recording material is manufactured, for example, by the method described in JP-A-49-11344 and JP-A-50-48930. Generally, a coating liquid in which a conductive substance, a basic dye mainly composed of the fluoran derivative of the present invention, and a color developer are dispersed together with a binder is applied to a support such as paper, or a conductive substance is coated on the support to form a conductive layer. The current-carrying heat-sensitive recording material of the present invention is produced by forming a coating material and applying thereon a coating liquid in which a dye, a color developer, and a binder are dispersed. Note that if both the dye and the color developer do not melt in the preferred temperature range of 70 to 120°C, sensitivity to Joule heat can be adjusted by using an appropriate thermofusible substance in combination.

The photosensitive recording material uses the fluoran derivative of the present invention, for example, Japanese Patent Publications No. 38-24188, No. 45-10550, No. 45-13258, No. 49-204, No. 49-62.
No. 12, No. 49-28449, JP-A No. 47-3161
No. 5, No. 48-32532, No. 49-9227, No. 49-135617, No. 50-80120, No. 50
-87317, No. 50-126228, etc.

Other ultrasonic recording media (French patent no. 2,120,922), electronic recording media (Belgium patent no. 7.959°986)
), electrostatic recording material (Japanese Patent Publication No. 49-3932), photosensitive printing material (Japanese Patent Publication No. 48-12104), stamping material (Japanese Patent Publication No. 47-10766), type ribbon (Japanese Patent Publication No. 49-1988)
No. 3713), ballpoint pen ink (JP-A-48-839)
No. 24), Crayon (U.S. Pat. No. 3'769,045)
Various types of recording materials such as No. 1) can be manufactured by using the fluoran derivatives of the present invention in place of conventional basic dyes and by the methods described in the respective patents.

The present invention will be explained in more detail by giving examples below, but the present invention is not limited to these unless it goes beyond the gist of the present invention. In addition, unless otherwise specified, parts and percentages in the examples are , each represents parts by weight and weight %.

[Example 1] 2-(2-hydroxy-4-diethylamino)benzoylbenzoic acid 0.011 mol 4-(o-biphenyl)
The mixture was reacted with 0.010 mol of aminophenol in 10 ml of concentrated sulfuric acid at room temperature for 24 hours.

The obtained reaction product was poured into 100 ml of ice water and incubated at room temperature for 2 hours.
After adjusting the pH to 9 by adding 0% aqueous sodium hydroxide solution, the resulting precipitate was filtered, washed with water, dried, and then recrystallized with methyl alcohol to obtain 3-diethylamino-7.
-(O-biphenyl)aminofluorane was obtained. In addition,
Yield 61%, m.

p,: 181-186°C, colored green-black on silica gel.

[Example 2] 80.011 mol of 2-(2-hydroxy-4-diethylamino)benzoylbenzoin and 0.010 mol of 3-methyl-4-(p-biphenyl)aminophenol methyl ether
mol and reacted in 15 ml of concentrated sulfuric acid at room temperature for 24 hours. The obtained reaction product was poured into ice water of 1QQm6, and a 20% aqueous sodium hydroxide solution was added at room temperature to PHII.
After that, 50ml of toluene was added and heated at 85°C for 3 hours.

Next, the toluene layer was separated, toluene was distilled off under reduced pressure, and then recrystallized from methyl alcohol to obtain 3-diethylamino-6-methyl-7-(p-biphenyl)aminofluorane. In addition, yield 85%, m, p,: 189 ~
It turned black on silica gel at 193°C.

[Examples 3 to 10] In place of 2-(2-hydroxy-4-diethylamino)benzoylbenzoic acid, the benzophenone conductor shown in Table 1 was used, and in place of 4-(0-biphenyl)aminophenol, 4-(0-biphenyl) shown in Table 1
Various fluoran derivatives were obtained in the same manner as in Example 1 except that the aminophenol M conductor was used. The yield of the obtained derivative and the color tone on silica gel are also listed in Table 1.

[Example 1l-16] In place of 2-(2-hydroxy-4-diethylamino)benzoylbenzoic acid, benzophenone derivatives shown in Table 2 were used, and 3-methyl-4-(p-biphenyl)aminophenolmethyl Various fluoran derivatives were obtained in the same manner as in Example 2, except that the 4-(p-biphenyl)aminophenol salt conductor shown in Table 2 was used instead of ether. The yield of the obtained derivative and the color tone on silica gel are also listed in Table 2.

[Example 17] A thermosensitive recording paper was produced using 3-diethylamino-7-(O-biphenyl)aminofluoran obtained in Example 1 in the following manner.

Fluoran derivative of Example 1 manufactured by A Liquid 5 parts Stearic acid amide 1 part 25 parts of 2% aqueous solution of hydroxyethyl cellulose This composition was ground to an average particle diameter of 2 microns using a sand grinder.

Preparation of Solution B 4. 50 parts of 4'-isopropylidene diphenol 10 parts of stearamide 250 parts of a 2% aqueous solution of hydroxyethyl cellulose This composition was ground to an average particle size of 2 microns using a sand grinder.

Liquid A manufactured by C Liquid 62 parts B
31 parts Ultrafine particulate anhydrous silica (trade name Thyroid 244, manufactured by Fuji Davison Chemical Co., Ltd.)
25 parts styrene-maleic anhydride copolymer salt 20%
Aqueous solution 175 parts Zinc stearate 5 parts Water
100 parts were mixed at the above ratio to prepare a coating liquid.

The obtained coating liquid was coated onto a base paper of 50 g/+rr so that the dry eyelid weight was 6 g/+yr to obtain a heat-sensitive recording paper. The resulting recording paper had a good white appearance with no background fog, and when it was pressed against a hot plate at 125 DEG C. for 5 seconds at a pressure of 4-/-, it developed a deep green-black color. This colored image had excellent light resistance and did not change color or disappear even when exposed to sunlight.

The thermal recording paper of this example was scanned at a scanning speed Q,
When recording was performed using a 7 m/sec cylindrical scanning recording tester, a recorded image exhibiting a high density green-black color was obtained.

[Example 18] 3-diethylamino-6-methyl- obtained in Example 2
5 m of 7-(p-biphenyl)aminofluorane was dissolved in isopropylated naphthalene and added to 350 parts of warm water (50°C) in which 25 parts of Bigskin gelatin with an isoelectric point of 8 and 25 parts of gum arabic were dissolved. Emulsified and dispersed. Add 1000 parts of warm water to this emulsion and adjust the pH to 4 to 1 with acetic acid.
After cooling to 10° C., 10 parts of a 25% aqueous gel tar aldehyde solution was added to harden the capsules.

This capsule-containing coating solution was coated on one side of a 45 g/rd base paper so that the dry weight was 5 g/nf, and on the other side, zinc 3.5-bis(α-methylbenzyl)salicylate was added to 200 parts of water. Pressure-sensitive recording paper was prepared by applying a color developer coating solution containing 20 parts of salt, 80 parts of kaolin, and 30 parts of the styrene-butadiene copolymer Emulgene (50% solids) to a dry weight of 5 g/rrf. (Middle paper) was obtained.

When several sheets were stacked and pressed so that the capsule-coated surface and the developer-coated surface faced each other, a black colored image was obtained on the developer-coated surface. This colored image had a faster color development rate than the colored cut portion, had a higher density than the initial printing stage, and showed no discoloration or fading even when exposed to sunlight.

[Example 19] 200 parts of cupric iodide and 5 parts of a 10% sodium sulfite aqueous solution were added to a 1% polyvinyl alcohol aqueous solution zooe and ground with a sand grinder until the average particle size was 2 microns. After adding 8 parts of polyacrylic acid ester emulsion and 20 parts of titanium oxide to this and sufficiently dispersing it,
It was coated on a base paper of 50 g/n (dry coating amount: 7 g/n).

3-diethylamino-7-(.

Example 17 except that 3-diethylamino-6-methyl-7-(p-biphenyl)aminofluorane obtained in Example 2 was used instead of -biphenyl)aminofluorane.
The dry coating amount of the heat-sensitive coating liquid prepared in the same manner as above was 5 g/
rd to obtain an electrically conductive heat-sensitive recording paper.

When this recording paper was recorded using a cylindrical scanning recording tester with a stylus force of 10 g and a scanning speed of 630 W/sec, a deep black recorded image was obtained. This recorded image has excellent light resistance,
It did not change color or fade when exposed to sunlight.

[Example 20] 6 g of 3-diethylamino-6-methyl-(p-biphenyl)aminofluorane obtained in Example 2 was dissolved in 40+njt of chloroform, and 10 g of polystyrene was added to the solution.
% benzene solution 40ml 1. A coating solution prepared by adding 5 g of carbon tetrabromide and stirring well was coated on double-sided polyethylene laminated paper in a dry coating amount of 5 g. After this, acetone/n-
It was fixed by washing with hexane=115. The colored image was stable even when exposed to sunlight.

Patent applicant: Kanzaki Paper Co., Ltd.

Claims (2)

[Claims] (1) Fluoran derivative c represented by the following general formula [1] In the formula, Rt and RZ each represent a Ct-Crt alkyl group or a C7-Cde aralkyl group, and X is a hydrogen atom, a halogen atom, C/~ C+ alkyl group or Ct=C
z represents an alkoxyl group, and Y represents a water atom, a halogen atom, or a C, -C, alkyl group. ] (2) 2-(2-hydroxy-4-amino)benzoylbenzoic acid represented by the general formula ([1)] and [in the formula R/
, R2 each represents a C/-C/J)7k+ group or a C7-Cdi aralkyl group. ]The following general formula CD
Biphenylaminophenol derivative represented by I) [wherein RJ represents a water m* atom or a c, -C2 alkyl group, and X is a hydrogen atom, a halogen atom, a C1 to C0 alkyl group, or a Cl-C1 alkoxyl Y represents a hydrogen atom, a halogen atom, or an alkyl group in which □Ct=C. ] The following general formula (1) is obtained by reacting with gold.
A method for producing a fluoran derivative represented by i7. V [wherein Ry, Rz, X, and Y have the above-mentioned meanings. ]
(3) Fluorane derivative represented by the following general formula [1] c In the formula, R1 and R2 each represent an alkyl group of C/ to C12 or an aralkyl group of 07 to C de, X is a hydrogen atom,
Halogen atom, Ct=C+ alkyl group or C-C2
represents an alkoxyl group, and Y represents a hydrogen atom, a halogen atom, or an alkyl group of C/C. ] A recording medium containing at least one portion of the following as an electron-donating color-forming substance.