JPS6361994B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a color-changing or color-developing material containing as a main component an indoline derivative with improved stability.

The present inventors discovered that certain indoline derivatives are useful as color-changing or color-developing materials, and filed a patent application. (Special application 1973-030042) After that,
As a result of intensive research and development from a practical perspective,
Furthermore, they have discovered a group of indoline derivatives that have excellent stability and are fully usable for practical use, and have completed the present invention.

That is, the present invention is based on the general formula [] Related to color-changing or color-developing materials characterized by causing color change or color development/decolorization by applying external stimulation energy such as light, heat, ions, electricity, pressure, radiation, etc. to the indoline derivative represented by It is. In the above formula, R represents an alkyl group or a phenyl group, R ₁ represents a lower alkyl group, R ₂ represents a lower alkyl group, a hydroxyalkyl group, or an alkoxyalkyl group, and R ₁ and R ₂ represent a 3-position It may also represent a group that forms a 5- or 6-membered hydrocarbon cyclic structure together with carbon. R ₃ represents hydrogen or an alkyl group, and Z
represents a methylene group or an ethylene group with or without an alkyl group, and A represents an aldehyde group or a nitroso group of a benzene ring aldehyde, a heterocyclic aldehyde, or a nitrosobenzene derivative and an active methyl group or a methylene group at the 2-position of the indoline nucleus. represents a dehydration condensation reaction residue with n represents a positive number of 2 or 3.

Here, examples of the benzene ring aldehyde include benzaldehyde, p-acetaminobenzaldehyde, p-bromobenzaldehyde, m-
Bromobenzaldehyde, O-bromobenzaldehyde, p-dimethylaminobenzaldehyde,
p-diethylaminobenzaldehyde, p-dibutylaminobenzaldehyde, O-chlorobenzaldehyde, p-chlorobenzaldehyde, p-
Anisaldehyde, O-anisaldehyde, p-
tolualdehyde, m-tolualdehyde, O-tolualdehyde, O-ethoxybenzaldehyde, p
-Ethoxybenzaldehyde, p-fluorobenzaldehyde, O-fluorobenzaldehyde,
p-nitrobenzaldehyde, m-nitrobenzaldehyde, O-nitrobenzaldehyde, p-
Cyanobenzaldehyde, O-cyanobenzaldehyde, 2.4-dichlorobenzaldehyde, 2.6-
Dichlorobenzaldehyde, 3.4-dichlorobenzaldehyde, 3.5-dichlorobenzaldehyde,
2.4-dimethoxybenzaldehyde, 2.5-dimethoxybenzaldehyde, 2.3-dimethoxybenzaldehyde, 3.5-dimethoxybenzaldehyde,
2.4-dimethylbenzaldehyde, 2.5-dimethylbenzaldehyde, 3.4-dimethylbenzaldehyde, 3.5-dimethylbenzaldehyde, veratraldehyde (3.4-dimethoxybenzaldehyde), 4-isopropylbenzaldehyde, O-
(2-chloroethyl)benzaldehyde, 2.4.6-
Trimethylbenzaldehyde (mesitaldehyde), 2.4.6-triethoxybenzaldehyde, 3.4
-Dimethyl-p-anisaldehyde, 2.5-dimethyl-p-anisaldehyde, 2-chloro-5-
Nitrobenzaldehyde, 2-chloro-6-nitrobenzaldehyde, 2-chloro-3-nitrobenzaldehyde, 5-chloro-2-nitrobenzaldehyde, vanillin, O-vanillin, isovanillin, 5-bromovanillin, 2- Chloro-4-
Dimethylaminobenzaldehyde, 2-chloro-
6-Fluorobenzaldehyde, 5-bromoveratraldehyde, 6-bromoveratraldehyde, 5-bromo-2-methoxybenzaldehyde, p-dimethylaminocinnamaldehyde, P
-diethylaminocinnamaldehyde, p-nitrocinnamaldehyde, O-nitrocinnamaldehyde, 2-chlorocinnamaldehyde, etc.

Further, examples of nitrosobenzene derivatives include p-dimethylaminonitrosobenzene, p-
Diethylaminonitrosobenzene, p-methylnitrosobenzene (p-nitrosotoluene), p-
Examples include nitronitrosobenzene, O-nitronitrosobenzene, 3-nitroso-2-nitrotoluene, and the like.

Examples of heterocyclic aldehydes include furfural, 5-methylfurfural, 5-bromofurfural, 4-isopropylfurfural, 2-thiophenecarboxaldehyde, 5-methylthiophenecarboxaldehyde, 3-methoxybenzothiophene- 2-carboxaldehyde,
2-pyridinecarboxaldehyde, 3-pyridinecarboxaldehyde, 4-pyridinecarboxaldehyde, 1-ethylindole-3-carboxaldehyde, 1-methylindole-3-carboxaldehyde, 1-methyl-2-carboxaldehyde Enylindole-3-carbosaldehyde, N-methylcarbazole-2-carboxaldehyde, N-ethyl-7
-Bromocarbazole-2-carboxaldehyde, N-(n-octyl)-7-nitrocarbazole-2-carboxaldehyde, benzofuran-
2-carboxaldehyde, dibenzofuran-2-
Carboxaldehyde, pyrrole-2-aldehyde, N-methylpyrrole-2-aldehyde, N-
Phenylpyrrole-2-aldehyde, 3-methylpyrrole-2-aldehyde, 2-ethylpyrrole-5-aldehyde, benzothiazole-2-aldehyde, 6-methylbenzothiazole-2-aldehyde, 6-chlorobenzothiazole-2 -Aldehyde, 5-chlorobenzothiazole-2-aldehyde, 6-methoxybenzothiazole-2-aldehyde, 5,6-dichlorobenzothiazole-
2-aldehyde, benzoselenazole-2-aldehyde, 6-methoxybenzozelenazole-2-
Aldehyde, 2,4-dimethylpyrrole-2-aldehyde, 4,6-dichloropyrimidine-5-carboxaldehyde, 2-formyl-4,6-dimethylpyrimidine, quinoline-2-aldehyde, acridine-10-aldehyde, 2 ,4-diphenyl-5,6,7-hexahydrobenzopyran-8
-Carboxaldehyde, 2,4-diphenyl-6
-Methyl-5,6,7-pentahydrobenzopyran-8-carboxaldehyde and the like.

Characteristics of the series of indoline derivatives used in the present invention include the following facts.

With the exception of some compounds, most of the compounds have absorption in the ultraviolet region and are colorless to pale yellow compounds.

These compounds are stimulated by external stimulus energy such as light, heat, ions, electricity, pressure, and radiation.
The following general formula [] It transitions to an indolenium-type ring-opening color-forming structure (styryl dye) represented by , and becomes a color-forming dye that covers the near-ultraviolet, visible, and near-infrared regions. Here, X represents an anion such as a halogen, an acid radical, or an alkoxy anion.

Dyes having an indolenium-type ring-opening coloring structure can be restored to their original indoline-type ring-closed coloring structure (the general formula of the present invention) by applying external stimulus energy in the opposite direction or by removing the external stimulus energy. Return to the structure of ).

Substituent ROnS on the benzene ring of the indoline nucleus
By introducing the group, it has become possible to easily obtain an indoline derivative of the general formula [] with higher purity compared to conventional synthetic methods.

These reversible changes in color development, decolorization, or discoloration can be achieved by adding a ROnS- group to the benzene ring of the indoline nucleus, which significantly improves the repeat life and stability.

The reversible change in coloration, fading, or discoloration changes between the two chemical structures of general formula [] and general formula [] by external stimulus energy. Therefore, since it is an organic substance, it is naturally subject to repeated deterioration, and as a result of long-term repetition, residual color appears and stability decreases. This point was significantly improved by introducing a ROnS group into the indoline ring as in the present invention.

By selecting the usage conditions of the dye, the solvent, additives, etc., both the life span and the stability can be further improved.

The colored structure can also be fixed by selecting appropriate conditions.

Next, typical specific examples of indoline derivatives suitably used in the present invention are listed, and the maximum absorption wavelength during ring closure and the maximum absorption wavelength during ring opening are also shown.

Compound 1 3,3-dimethyl-5-methylsulfonyl-2-(paradimethylaminostyryl)-indolino[2,1-
b]-oxazol-5-one Maximum absorption wavelength during ring closing 294-5 nm (in acetonitrile) Ring opening 567-8 nm (methanol/acetic acid) Compound 2 3,3-dimethyl-5-methylsulfonyl-2-(paramethoxystyryl) indolino [2,1- b]-oxazol-5-one Maximum absorption wavelength during ring closing 270-271 nm (n-hexane/acetonitrile) Ring opening 447-449 nm (methanol/acetic acid) Compound 3 3,3-dimethyl-5-methylsulfonyl-2-[2-(9-methylcarba) zolyl)vinyl]-indolino[2,1-b]-oxazolo-5-
on Maximum absorption wavelength during ring closing 280-281 nm (n-hexane/acetonitrile) Ring opening 524-526 nm (methanol/acetic acid) Compound 4 3,3-dimethyl-5-(n-butylsulfonyl)-2-(paradimethylamino) styryl) indolino[2,1-b]oxazol-5-one Maximum absorption wavelength during ring closure 297-298nm (acetonitrile) Ring-opening 568-570nm (methanol/acetic acid) Compound 5 3,3-dimethyl-5-methylsulfonyl-2-[2-(1-methyl-
2-phenyl-3-indolyl)vinyl]indolino[2,1-b]oxazol-5-one Maximum absorption wavelength during ring closure 246-248nm, 270nm (benzene/acetonitrile) Ring-opening 508-510nm (methanol) Compound 6 3,3-dimethyl-5-methylsulfonyl-2-[2-(1-ethyl-
3-indolyl)vinyl]indolino[2,1-b]oxazolo-5-
on Maximum absorption wavelength during ring closing 265nm 291-292nm (benzene/acetonitrile) Ring opening 〃 512nm (methanol) Compound 7 3,3-dimethyl-5-phenylsulfonyl-2-(paradimethylaminostyryl) indolino [2,1-
b] Oxazol-5-one Maximum absorption wavelength during ring closure 297-299nm (acetonitrile) Ring-opening 572-3nm (methanol/acetic acid) Compound 8 3,3-dimethyl-5-phenylsulfonyl-2-(parabromostyryl)indolino[2,1- b] Oxazol-5-one Maximum absorption wavelength during ring closing 269-270 nm (benzene/acetonitrile) Ring opening 〃 402-405 nm (methanol) Compound 9 3,3-dimethyl-5-(n-octylsulfonyl)-2-(paradimethylaminostyryl) indolino [ 2,1-b]Oxazol-5-one Maximum absorption wavelength during ring closing 298 nm (n-hexane/acetonitrile) Ring opening 〃 570-571 nm (methanol) Compound 10 3,3-dimethyl-5-methylsulfonyl-2-(paradimethylaminocinnamylidenevinyl) indolino [2 ,1-b]Oxazol-5-one Maximum absorption wavelength during ring closing 329-331 nm (benzene/acetonitrile) Ring opening 〃 644-645 nm (methanol) Compound 11 3,3-dimethyl-5-methylsulfonyl-2-(paradimethylaminostyryl) indolino [2,1-
b] Oxazin-6-one Maximum absorption wavelength during ring closing 296nm (n-hexane/acetonitrile) Ring opening 570nm (methanol/acetic acid) Compound 12 3,3-dimethyl-5-phenylsulfonyl-2-[2-(9-ethylcarbazolyl) vinyl]indolino[2,1-b]oxazin-6-one Maximum absorption wavelength during ring closing 281-3 nm (benzene/acetonitrile) Ring opening 526-527 nm (methanol/acetic acid) Compound 13 3,3-dimethyl-5-methylsulfonyl-2-(orthochlorostyryl) indolino [2,1 -b] Oxazol-5-one Maximum absorption wavelength during ring closing 245-248 nm (n-hexane/acetonitrile) Ring opening 411-412 nm (methanol) Compound 16 3,3-dimethyl-5-methylsulfonyl-2-(3,4-dimethoxystyryl) indolino [ 2,1-
b] Oxazol-5-one Maximum absorption wavelength during ring closing 258-260nm (n-hexane/acetonitrile) Ring-opening 455-457nm (methanol/acetic acid) Compound 17 3,3-dimethyl-5-(n-butylsulfonyl)-2-{para(dimethyl) ―
n-butylamino)styryl}indolino[2,1-b]oxazolo-
5-on Maximum absorption wavelength during ring closing 298-300nm (benzene/acetonitrile) Ring opening 567-568nm (methanol/acetic acid) Compound 18 3,3-dimethyl-5-methylsulfonyl-2-(paradimethylamino-2-azastyryl) indolino [2,1-b]Oxazol-5-one Maximum absorption wavelength during ring closing: 928-300nm (benzene/acetonitrile) Ring-opening: 609-611nm (methanol/acetic acid) Compound 19 3,3-dimethyl-5-methylsulfonyl-2-{1-methyl-(paradimethylamino) styryl}indolino[2,1-b]oxazolo-5
-on Absorption maximum wavelength during ring closing 292-3 nm Ring opening 〃 565-7 nm Compound 20 3,3-dimethyl-5-phenylsulfonyl-2-(paradimethylaminostyryl) indolino [2,1-
b]-(4-methyl)oxazolo-
5-on Maximum absorption wavelength during ring closing 295-297nm (n-hexane/acetonitrile) Ring opening 〃 570nm (methanol/acetic acid) Compound 21 3-Methyl-3-ethoxymethyl-
5-Methylsulfonyl-2-(paradimethylaminostyryl)indolino[2,1-b]oxazolo-5-
on Maximum absorption wavelength during ring closing 294-5 nm (n/hexane/acetonitrile) Ring opening 563-4 nm (methanol/acetic acid) Compound 22 3,3-dimethyl-5-methylsulfonyl-2-(3,4-methylenedioxy Styril) Indolino [2,
1-b] Oxazol-5-one Maximum absorption wavelength during ring closing 263-265nm (n-hexane/acetonitrile) Ring opening 462-463nm (methanol/acetic acid) Compound 23 3-Methyl-3-hydroxyethyl-5-methylsulfonyl-2-
(paradimethylaminostyryl)indolino[2,1-b]oxazol-5-one Maximum absorption wavelength during ring closure 293-295nm (n-hexane/acetonitrile) Ring-opening 563-565nm (methanol/acetic acid) Compound 24 3,3-dimethyl-5-(n-butoxysulfonyl)-2-[2-( 9
-methylcarbazolyl)vinyl]indolino[2,1-b]oxazol-5-one Maximum absorption wavelength during ring closure 282-284nm (n-hexane/acetonitrile) Ring-opening 524-526nm (methanol/acetic acid) Compound 25 5-Methylsulfonyl-spiro[3,1']cyclohexane-2-
(paradimethylaminostyryl)indolino[2,1-b]oxazol-5-one Maximum absorption wavelength during ring closing 297nm (n-hexane/acetonitrile) Ring opening 568nm (methanol/acetic acid) Compound 26 5-Methylsulfonyl-spiro[3,1′]cyclopentane-2-
(paradimethylaminostyryl)indolino[2,1-b]oxazol-5-one Maximum absorption wavelength at ring closing: 297 nm (n-hexane/acetonitrile) Ring opening: 567 nm (methanol/acetic acid) Next, examples of the present invention will be described in detail.

Example 1 Compound 1 was dissolved in a mixture of acetonitrile and n-hexane, applied to paper, and after evaporating the solvent,
When exposed to ultraviolet light, it develops a purple-pink color. Moreover, it continues to maintain its colored state for a long time even after UV irradiation is removed. This is thought to be due to the fact that after Compound 1 is excited by ultraviolet rays, it maintains a ring-opening color-developing structure due to the negative groups or anions contained in the paper and the dissociated protons of water.

When the indoline derivative of the present invention in which a methylsulfonyl group is bonded to the 5-position of the indoline ring and the conventional indoline derivative described in Japanese Patent Application No. 51-030042 are compared in terms of the color development excited by ultraviolet rays, when continuously irradiated with ultraviolet rays, the conventional indoline derivative The color begins to fade in 2 to 3 hours, but the compound used in the present invention did not show any color fading for about 10 hours.

Other indoline derivatives have similar effects; for example, when Compound 19 is applied to paper in a similar manner, the color changes from pale yellow to pink when exposed to ultraviolet light. Ultraviolet rays are preferable as the light to be irradiated because they have high energy, but the same effect can be obtained with visible light over time.

Example 2 Compound 7 and tetrabutylammonium perchlorate were dissolved in γ-butyrolactone at 0.1 mol/d, and the solution was sealed in a glass cell having a transparent electrode as shown in FIG. In the figure, 1 and 3 are glass, 2 and 4 are transparent conductive films made of indium oxide, 5 is an epoxy resin that also serves as a sealer and a spacer, and 6 is the above-mentioned solution in which compound 7 is dissolved. Now, when a DC voltage is applied between electrodes 2 and 4, compound 7 develops a pinkish purple color. The voltage to be applied should be 1.0 to 1.5V. It returns to its original state when the applied voltage is removed. In particular, if a DC voltage of opposite polarity is applied during color development, the color erasure speed is fast and the color quickly returns to its original state. In this case, the present invention has a 10 times longer lifetime for repeated color development and decolorization compared to the corresponding conventional indoline derivatives. The same effect can be obtained with other indoline derivatives. Other suitable solvents include aprotic polar solvents such as acetonitrile, propylene carbonate, dimethylformamide, and dimethyl sulfoxide.

As the supporting salt, well-known tetraethylammonium perchlorate, tetramethylammonium hexafluorophosphate, etc. can also be used. The dissociated ions of the supporting salt are involved in the coloring and fading caused by the application of voltage in this manner, and are caused by oxidation-reduction with the electrode.

Example 3 Compound 3 was dissolved in dimethyl sulfoxide,
Insert between two glass plates. When heated, the color changes from colorless to wine red at around 110℃. When the temperature is lowered, it returns to its original colorless state, and the color changes and fades reversibly with heat. This thermal color development occurs at a point slightly lower than the melting point of the compound. However, if there are protons or anions in the environment, the color develops at an even lower temperature. Other derivatives have similar effects; they develop color when heated and return to their original color when the heat is removed and the temperature falls.

For example, Compound 4 develops a purple color at 125°C in dimethyl sulfoxide, and develops a color at about 70°C when dissolved in dimethyl sulfoxide to which a small amount of methyl alcohol has been added. In this way, as the proton concentration increases within the system, color develops at lower temperatures.

Example 4 Compound 9 is dispersed in gelatin so as not to come into contact with bentonite and is coated thinly on paper using a rotary coating plate. The pigment is initially colorless, but when pressure is applied, the pigment and bentonite come into contact only in the pressurized areas, and the pigment develops a reddish-pink color.

In this case, conventional indoline derivatives had the disadvantage of poor stability and, for example, partial coloring due to humidity in the air even though they were mixed with bentonite and kept in a decolored state.However, the present invention The indoline derivative used for this purpose has good stability and can easily maintain its decolorized state.

Example 5 Compound 5 and hydroquinone are dissolved in a dimethyl sulfoxide aqueous solution, dispersed in gelatin, and then applied to paper. When it is irradiated with radiation such as electron beams, alpha rays, and gamma rays, it develops a deep wine red color. When the radiation irradiation is stopped, this colored state remains for a while, and then returns to the decolored state. The indoline derivatives used in the present invention fade by one order of magnitude slower than conventional ones.

As mentioned above, the color-changing or color-developing material according to the present invention is as follows:
reversible by applying external stimulation energy such as light, heat, ions, electricity, pressure, radiation, etc.
In addition, since it can irreversibly develop and fade color, it is used in display materials, recording materials, sensing materials, etc., and its industrial potential is great.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a display device incorporating an indoline derivative according to the present invention.

Claims (1)

[Claims] 1. General formula [] (In the formula, R represents an alkyl group or a phenyl group, R ₁ represents a lower alkyl group, R ₂ represents a lower alkyl group, a hydroxyalkyl group, or an alkoxyalkyl group, and R ₁ and R ₂ represent the 3rd carbon May also represent a group forming a 5- or 6-membered hydrocarbon cyclic structure together with R ₃ represents hydrogen or an alkyl group, Z represents a methylene group or ethylene group with or without an alkyl group, and A represents a group that forms a 5- or 6-membered hydrocarbon cyclic structure. Represents a dehydration condensation reaction residue between the aldehyde group or nitroso group of a benzene ring aldehyde, heterocyclic aldehyde or nitrosobenzene derivative and the active methyl group or methylene group at the 2-position of the indoline nucleus,
n represents a positive number of 2 or 3. Here, the benzene ring aldehyde refers to a benzaldehyde derivative or a cinnamaldehyde derivative, and the benzaldehyde derivative is a benzene having one or two substituents selected from a halogen, a dialkylamino group, a lower alkoxy group, or a methylenedioxy group. Cyclic aldehydes are shown, cinnamaldehyde derivatives are those having a dialkylamino group, and heterocyclic aldehydes are 2-
An aldehyde directly bonded to the heterocycle of N-alkylindole or N-alkyl-2-carbazole which may be substituted with a phenyl group is shown, and the aromatic nitroso compound is para-dialkyl aminonitrosobenzene. ) A material for color change or color development/decolorization, which is characterized by causing color change or color development/decolorization by applying external stimulating energy such as light, heat, ions, electricity, pressure, radiation, etc. to the indoline derivative represented by .