JPH0570701A - Bislactone compound and its production - Google Patents

Abstract

PURPOSE:To provide a bislactone compound and its production process which compound is for use as an electron-donating colorless dye in recording materials such as thermal recording paper, pressure-sensitive paper, and photo-and pressure-sensitive paper and is excellent in shelf stability and light and chemical resistances. CONSTITUTION:A bislactone compound represented by the formula. This compound is produced by reacting a 3,3'-dimethoxydiphenyl compound with 2- hydroxybenzoylbenzoic acid.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention is an electron-donating colorless dye for recording materials such as heat-sensitive paper, pressure-sensitive paper, and light-sensitive pressure-sensitive paper, and exhibits high storability and excellent light resistance and chemical resistance. A bislactone compound and a method for producing the same are provided.

[0002]

2. Description of the Related Art Recording materials using an electron-donating colorless dye and an electron-accepting compound are already well known as pressure-sensitive paper, thermal paper, photosensitive pressure-sensitive paper and the like. For example British Patent 214
0449, 21659593, 2166882, 2
174504, U.S. Pat.
20, Japanese Patent Publication No. 60-23992, JP-A No. 57-1798.
36, the same 60-123556, the same 60-123557,
Details are the same as 61-230134. The recording material should have (1) sufficient color density and color sensitivity, (2) no fog, (3) sufficient fastness of the color body after color development, 4) Appropriate color hue and suitability for copiers, (5) High S / N ratio, (6) Sufficient chemical resistance of the coloring body. In recent years, with the speeding up of recording systems and the diversification of requirements, research has been earnestly conducted to improve these characteristics. The present inventors have found that the characteristics of the recording material are significantly improved by incorporating a unique device into the electron-donating colorless dye.

[0003]

DISCLOSURE OF THE INVENTION The present invention is to provide a bislactone compound which is thermally stable, has low solubility, excellent storage stability, and excellent light resistance, and a method for producing the same.

[0004]

The above object has been achieved by developing a bislactone compound represented by the general formula (1). General formula (1)

[0005]

[Chemical 4]

In the formula, R ₁ and R ₂ represent a hydrogen atom, an optionally substituted alkyl group or an aryl group, R ₃ is a single bond,
And a divalent group, and R _{4 to} R ₆ represent a hydrogen atom, an acyl group, an alkyl group, an alkoxy group, a halogen atom, a nitro group, or aryl. The compound of the general formula (1) is obtained by reacting the 3,3′-dimethoxydiphenyl compound represented by the general formula (2) with 2-hydroxybenzoylbenzoic acid represented by the general formula (3). General formula (2)

[0007]

[Chemical 5]

R₃Represents a single bond and a divalent group, for example
For example, alkylene, alkenylene, -CO ₂-, -SO₂
-, -S-, -O-, -CONH-, or general formula (4).
R represents a linking group represented by₇Is a hydrogen atom, al
Represents a kill group, an aryl group, or an acyl group, X is —CO—,
-SO₂-, -CONH-, -CO₂-, N is 0 or 1
Represents General formula (4)

[0009]

[Chemical 6]

R ₄ is a hydrogen atom, an acyl group, an alkyl group,
It represents an alkoxy group, an aryloxy group, a halogen atom, a nitro group, or an aryl group. General formula (3)

[0011]

[Chemical 7]

In the formula, R ₁ and R ₂ represent a hydrogen atom, an optionally substituted alkyl group, a phenyl group, an aryl group such as a naphthyl group, and these are an alkyl group, an alkoxy group, an aryloxy group, a halogen atom, It may have a substituent such as a nitro group or an aryl group. The alkyl group represents a saturated or unsaturated alkyl group or cycloalkyl group, which may have a substituent such as an aryl group, an alkoxy group, an aryloxy group, a halogen atom or a cyano group. Among the substituents represented by R ₁ and R ₂ in the formula, hydrogen atom, an alkyl group having 1 to 18 carbon atoms, and 6 carbon atoms
To 12 aryl groups are preferable, and these may be substituted with a halogen atom, an alkoxy group, an aryl group, an aryloxy group, an acyl group, a cyano group, a pyridyl group, a furfuryl group or the like. R ₁ and R ₂ may combine with each other to form a 5- or 6-membered ring. R _{5 to} R ₆ represent a hydrogen atom, an acyl group, an alkyl group, an alkoxy group, an aryloxy group, a halogen atom, a nitro group, or an aryl group.
The electron-donating colorless dye according to the present invention has high solubility in an organic solvent, and when it comes into contact with an electron-accepting substance,
It has the advantage of developing color quickly. The color-developed dye is extremely stable as compared with the dyes produced from the existing color-developing agents, hardly discolors due to long-term light irradiation and heating, and is particularly advantageous from the viewpoint of long-term storage of records. or,
The color former is excellent in stability, does not deteriorate even after long-term storage, and has a sufficient color-forming ability. It has a performance close to ideal as a color-forming agent for recording materials such as pressure-sensitive paper and thermal paper.

Specific examples of the starting materials to be used in the present invention include 3,3'-dimethoxydiphenyl, 3,3'-
Dimethoxydiphenylamine, 3,3'-dimethoxydiphenylmethylamine, 3,3'-dimethoxydiphenyl-N-phenoxyacetylamine, 3,3'-dimethoxydiphenyl-N-hexylamine, 3,3'-dimethoxydiphenyl-N- Methanesulfonylamine,
3,3′-dimethoxydiphenyl-Np-toluenesulfonylamine, 3,3′-dimethoxybenzophenone, 3,3′-dimethoxydiphenylsulfone, N,
N-bis-3-ethoxyphenyl-N-phenylurea, N-phenyl-N'-3,3'-dimethoxydiphenylurea, N-hexyl-N'-3,3'-dimethoxydiphenylurea and the like can be mentioned. It is represented by the general formula (2). General formula (2)

[0014]

[Chemical 8]

Specific examples of 4-substituted amino-2-hydroxybenzoylbenzoic acid include 2-hydroxy-4-dibutylaminobenzoylbenzoic acid and 2-hydroxy-4.
-Diethylaminobenzoylbenzoic acid, 2-hydroxy-4-N-ethyl-p-toluidino-benzoylbenzoic acid, 2-hydroxy-4-N-ethyl-N-isobutyl-benzoylbenzoic acid, 2-hydroxy-4-N- Ethyl-N-tetrahydroxyfurfurylmethyl-benzoylbenzoic acid, 2-hydroxy-4-N-ethyl-N-isoamyl-benzoylbenzoic acid, 2-hydroxy-4-
N-propyl-N-γ-ethoxypropyl-benzoylbenzoic acid, 2-hydroxy-4-N-ethyl-N-β-
Phenoxyethyl-benzoylbenzoic acid, 2-hydroxy-4-N-ethyl-N-γ-p-ethylphenoxypropyl-benzoylbenzoic acid, 2-hydroxy-4-N
-Ethyl-N-cyclohexylamino-benzoylbenzoic acid and the like are mentioned and represented by the general formula (3). General formula (3)

[0016]

[Chemical 9]

As the compound of the present invention, it is preferable to use the 3,3'-dimethoxydiphenyl compound represented by the general formula (2) and the compound of the general formula (3), and the compound of the general formula (2) and the general formula (3). The compound of 1) is prepared in an acidic solvent with a molar ratio of 1: 2 to 1: 2.2. These are -10
React at -50 ° C for 2-8 hours. When the acidic solvent is sulfuric acid, 60% or more, preferably 80 to 100%
Is. Higher concentrations than the more dilute acids are effective in keeping the reaction liquid. Other acidic condensation solvents such as sulfuric acid and fuming sulfuric acid, phosphoric anhydride, polyphosphoric acid and zinc chloride,
Mixtures with certain Lewis acids such as phosphorus oxychloride can also be used. Sulfuric acid is a preferred condensation solvent because of its low cost, ease of handling and non-volatility, the reaction can be easily cooled and diluted in ice water and then the reaction product can be directly processed. As the recrystallization solvent, aromatic hydrocarbons such as benzene and toluene, halogenated hydrocarbons such as monochlorobenzene, dichlorobenzene and chloroform, and alcohols such as methanol, ethanol and propanol are used. Specific examples of the compound of the present invention are shown below.

[0018]

[Chemical 10]

[0019]

[Chemical 11]

[0020]

[Chemical formula 12]

Examples will be shown below, but the present invention is not limited to these examples.

[0022]

【Example】

Example 1 0.01 mol of 3,3'-dimethoxydiphenyl and 2-hydroxy-4-diethylaminobenzoylbenzoic acid.
02 mol is taken up in 8 ml of ice-cooled concentrated sulfuric acid and 2 ml of fuming sulfuric acid. Stir at room temperature for 2 hours, then at 30 ℃
Stir it. The product was then isolated by pouring the mixture into ice-cold water containing twice the molar equivalent of caustic soda while stirring. A specific example compound (1) that exhibits a vermilion color upon contact with BPA by column chromatography using silica gel with acetonitrile / chloroform as a developing solvent.
A target product having a melting point of 275 ° C. was obtained. Example 2 In place of 3,3′-dimethoxydiphenyl of Example 1,
3,3'-dimethodiphenylamine was used. Other than the above, the same procedure as in Example 1 was carried out to obtain the target product having a melting point of 235 ° C., which is represented by the specific compound (6) and has a dark blue color when contacted with BPA. Example 3 In place of 3,3′-dimethoxydiphenyl of Example 1,
3,3'-Dimethodiphenylmethylamine was used.
By the same method as in Example 1 except for the above, the target product having a melting point of 210 ° C., which was represented by the specific compound (7) and exhibited a dark blue color when contacted with BPA, was obtained. Example 4 Instead of 3,3′-dimethoxydiphenyl of Example 1,
3,3'-Dimethoxydiphenyl-phenoxyacetylamine was used. Otherwise, the same method as in Example 1 was followed.
A target product having a melting point of 260 ° C., which is represented by the specific example compound (10) and exhibits a dark blue color when contacted with, was obtained.

Claims (2)

[Claims] 1. A bislactone compound represented by the general formula (1): In the formula, R ₁ and R ₂ represent a hydrogen atom, an optionally substituted alkyl group or an aryl group, R ₃ represents a single bond or a divalent group, and R _{4 to} R ₆ represent a hydrogen atom, an acyl group or an alkyl group. Represents a group, an alkoxy group, a halogen atom, a nitro group, and an aryl group. 2. A bislactone according to claim 1, wherein 3,3′-dimethoxydiphenyl represented by the general formula (2) is reacted with 2-hydroxybenzoylbenzoic acid represented by the general formula (3). Method for producing compound General formula (2) In the formula, R ₃ represents a single bond or a divalent group, and R ₄ represents a hydrogen atom, an acyl group, an alkyl group, an alkoxy group, a halogen atom, a nitro group or an aryl group. General formula (3) In the formula, R ₁ and R ₂ represent a hydrogen atom, an optionally substituted alkyl group and an aryl group, and R _{5 to} R ₆ represent a hydrogen atom, an acyl group, an alkyl group, an alkoxy group, a halogen atom, a nitro group and an aryl group. Represents.