JPH09323990A - Merocyanine-pyrrole conjugate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new merocyanine-pyrrole conjugate having characteristics decomposable under the action of light, thermal energy or an acid by directly bonding a spiropyran which is a photochromic compound constituting a material having high functionality to pyrrole which is a monomer constituting an electrically conductive polymer. SOLUTION: This conjugate of formula I (R is an alkyl, an aromatic hydrocarbon, etc.) has a structure to be obtained by chemically bonding the carbon at the 2-position of merocyanine, which is a ring-opened body of a spiropyran of formula II having a nitro group at the 6'-position, to the nitrogen of pyrrole. This kind of a conjugate can be used, e.g. as a raw material for an information inversion material, an optically recording material, an optical element, etc., or a protecting compound for spiropyran or pyrrole.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel compound in which merocyanine, which is a ring-opened form of spiropyran having a nitro group at the 6'-position, is chemically bonded to pyrrole. The present invention relates to a merocyanine-pyrrole conjugate decomposable into spiropyran and pyrrole by action. The merocyanine-pyrrole conjugate of the present invention is used, for example, as a raw material for an information conversion material, an optical recording material, an optical element, a nonmetallic conductor, a sensor, and the like, and also as a protective compound for spiropyran and pyrrole.

[0002]

2. Description of the Related Art Spiropyran compounds are typical photochromic compounds, and are known to be promising as functional organic materials because they reversibly develop and decolor by light or heat energy (Japanese Patent Application Laid-Open No. Sho 63-163). 128318, JP-A-62-95287, etc.). In order to produce a photochromic pattern or an image using a spiropyran compound, a method of irradiating light through a negative mask pattern or applying or printing in a pattern as a paint or ink is generally used.

[0003] Certain pyrroles are polymerized into polypyrrole, which is a conductive polymer, and this polypyrrole is expected as a new conductive material.
A compound that protects spiropyran or pyrrole and can easily release them as needed is not known yet.

[Problems to be Solved by the Invention]

However, when producing a photochromic pattern or an image using a spiropyran compound, there is a problem that the above method is a temporary patterning and cannot be stored as a permanent pattern. Further, according to the above method, it is difficult to form a fine pattern. Thus, according to the conventional technique, it is difficult to obtain a permanent and fine photochromic pattern. In addition, pyrrole has a drawback that storage stability is poor because it is easily oxidized by reacting with oxygen in the air. Furthermore, since typical pyrrole is liquid at room temperature and has volatility, it has been difficult to operate it when mixing a fixed amount in a matrix polymer or the like.

The present invention has been made in view of the above problems, and has as its object to provide a novel compound having a property of decomposing into spiropyran and pyrrole by light, heat energy or acid.

[0006]

Means for Solving the Problems The present inventors have directly formed a chemical bond between spiropyran, which is a photochromic compound attracting attention as a highly functional material, and pyrrole, which is a monomer of polypyrrole, which is a conductive polymer. A new spiropyran derivative was synthesized. Then, they have found that this compound has a property of decomposing into spiropyran and pyrrole by light, heat energy and acid, thereby completing the present invention.

That is, the merocyanine-pyrrole conjugate of the present invention is a compound represented by the following general formula (I) represented by the following chemical formula 1, which is a ring-opened spiropyran (II) having a nitro group at the 6′-position. Having a structure in which the 2-position carbon of merocyanine and the N-position of pyrrole are chemically bonded. In the general formulas (I) and (II), R represents an alkyl group, an aromatic hydrocarbon group or an aromatic hydrocarbon group having an alkylene group interposed therebetween, and the aromatic hydrocarbon group is an alkyl group. , Fluorine, chlorine, bromine, an alkoxy group or an amino group. Further, in the general formula (I), each carbon of the pyrrolyl group and carbons at positions 4 to 7, 3 ', 4', 6 ', α and β have hydrogen, an alkyl group, fluorine, chlorine or bromine. Can be.

The R group may be an alkyl group such as a methyl group and an ethyl group. Further, this R group is
It may be an aromatic hydrocarbon group or an aromatic hydrocarbon group having an alkylene group interposed. Here, the term “aromatic hydrocarbon group having an alkylene group interposed therein” means, for example, that _n in the case of — (CH ₂ ) _n —Ph can be 2 or more besides the benzyl group. Other alkylene groups can be substituted for the groups. Further, the aromatic nucleus substituent of the aromatic hydrocarbon group may be an alkyl group such as methyl and ethyl, an alkoxyl group such as methoxy and ethoxy, and an amino group such as dimethylamino group. Or it may be bromine.

The carbons of pyrrole and the carbons at positions 4 to 7, 3 'to 5', 7 'and 8' of spiropyran (II) are each hydrogen, an alkyl group such as a methyl group or an ethyl group, fluorine, It can have chlorine or bromine substituents.

The method for producing the merocyanine-pyrrole conjugate of the present invention is not particularly limited, and a compound having a structure in which merocyanine, which is a ring-opened form of spiropyran (II), is directly chemically bonded to pyrrole is synthesized. Any method is acceptable. Representative production methods include the following (1) and
There is one shown in (2).

(1) Spiropyran having a predetermined substituent is added to pyrrole potassium formed by reacting pyrrole and metal potassium at room temperature in a solvent such as tetrahydrofuran (THF) and reacted at room temperature.
A synthetic route by this method is shown in Chemical formula 2.

[0012]

Embedded image

(2) Spiropyran having a substituent at a predetermined position is added to a mixed solution in which potassium alkoxide such as potassium t-butoxide and pyrrole are dissolved in a solvent such as THF, and reacted at room temperature. According to this synthesis method,
There is an advantage that the target product can be manufactured without using metal potassium which is difficult to handle. The synthetic route by this method is shown in Chemical formula 3.

[0014]

Embedded image

In the above methods (1) and (2), a nitro-substituted spiropyran is used as a reaction raw material. The production method of the nitro-substituted spiropyran is not particularly limited, but is usually produced by reacting an indoline with a nitrosalicylic aldehyde.

The merocyanine-pyrrole conjugate of the present invention has a structure in which merocyanine, which is a ring-opened form of spiropyran, which is an organic compound having photochromic properties, and pyrrole, which is a raw material of a conductive polymer, are directly chemically bonded. Is a new compound. The merocyanine-pyrrole conjugate can be obtained by giving thermal energy alone to the compound, or by giving light or thermal energy in a state where the compound is contained in a solvent or a polymer matrix, or by adding this compound to a compound such as hydrochloric acid. It is a compound having a previously unknown property that the original spiropyran and pyrrole can be easily released by treatment with an acid.

In the merocyanine-pyrrole conjugate of the present invention, spiropyran useful as a photochromic compound is concealed. Then, spiropyran can be extracted from this conjugate at any desired place by utilizing the above-mentioned property of releasing spiropyran and pyrrole by, for example, heat treatment. Therefore,
According to the conjugate of the present invention, a photochromic pattern expected to be applied as an information conversion material for reversible optical recording or the like can be easily produced.

Further, pyrrole, which is a conductive polymer material, was conventionally stored as a liquid. However, according to the compound of the present invention, pyrrole can be stabilized and stored as a solid, and if necessary, heated. It can be taken out at any place by processing or the like. Therefore, the compounds of the present invention can be applied to the production of conductive polymers. This conductive polymer is used, for example, as a sensor material. Thus, a compound capable of masking spiropyran or immobilizing pyrrole has not been known so far. Therefore, the merocyanine of the present invention
According to the pyrrole conjugate, development of new applications can be expected.

[0019]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to examples and application examples. (1) Production of merocyanine-pyrrole conjugate (Example 1) A merocyanine-pyrrole conjugate (A) was produced by the following production method. 0.7 g of pyrrole (0.3 g) was placed in a three-necked flask equipped with a nitrogen inlet, a reflux condenser, a thermometer, a silicon septum, a magnetic stirrer, and the like.
01 mol), and anhydrous tetrahydrofuran (THF)
30 ml was added and dissolved. 0.4 g (0.01 mol) of potassium thinned with a sodium press in this solution
Was added under a nitrogen atmosphere, and the mixture was stirred and reacted at room temperature until metallic potassium disappeared. Then, while cooling the obtained pyrrole potassium solution in an ice bath, 1,3,3-trimethyl-6′-nitrospiro [2H-1′-benzopyran-
2 ', 2-Indoline] 3.2 g (0.01 mol)
A solution dissolved in 30 ml of HF was added dropwise with a syringe. After the addition, the ice bath was removed, and the mixture was stirred at room temperature for 2 hours to carry out an addition reaction. The progress of the reaction was checked using a thin-layer chromatograph. After completion of the reaction, a small amount of methanol is added to decompose residual pyrrole potassium, etc.,
Water was added, the mixture was transferred to a separating funnel, and THF extraction was performed. T
After adding sodium sulfate to the HF layer and drying, THF as a solvent was removed under reduced pressure at room temperature. The resulting brown powdery solid was washed with carbon tetrachloride and purified to obtain 1.5 g of an adduct. Here, the isolation yield was 39%. FIG. 1A shows an NMR chart of the adduct obtained in Example 1, and FIG. 2 shows an IR chart thereof. The results of elemental analysis of this adduct are shown in Table 1 below. The value shown as “calculated value” in Table 1 is a theoretical value obtained by calculating the composition formula of this adduct as C ₂₃ H ₂₃ N ₃ O ₃ .

Table 1 −−−−−−−−−−−−−−−−−−−−−−−−−−−−−− C H N −−−−−−−−−−−−−−− −−−−−−−−−−−−−−−−−−− Calculated value (%) 70.93 5.95 10.79 Measured value (%) 70.63 5.95 10.64 −−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−

From the above results, this adduct may be a merocyanine-pyrrole conjugate (A) (hereinafter referred to as “adduct A”) corresponding to R ＝ CH ₃ (methyl group) in the above chemical formula 1. It could be confirmed.

(Example 2) A merocyanine-pyrrole conjugate (A) was produced by the following production method instead of the production method of Example 1. 1.2 g of potassium t-butoxide in a three-necked flask equipped with a nitrogen inlet, a reflux condenser, a thermometer, a silicon septum, a magnetic stirrer, and the like.
(0.01 mol), and dissolved by adding 20 ml of THF. 0.7 g (0.01 mol) of pyrrole was added to this solution.
Was dissolved in 20 ml of THF under a nitrogen atmosphere, and the mixture was stirred and reacted at room temperature. Next, 1,3,3-trimethyl-6′-nitrospiro [2H
-1'-benzopyran-2 ', 2-indoline] 3.2
g (0.01 mol) in 40 ml of THF was added dropwise. After completion of the dropwise addition, the mixture was stirred at room temperature for several hours to carry out an addition reaction. The progress of the reaction was checked using a thin-layer chromatograph. After the completion of the reaction, water was added, the mixture was transferred to a separatory funnel and extracted with THF, and washed with a saturated aqueous solution of potassium chloride until the aqueous layer became neutral. TH
After adding sodium sulfate to the F layer and drying, THF as a solvent was removed under reduced pressure at room temperature. Then, it was washed with carbon tetrachloride and purified in the same manner as in Example 1 to obtain 1.7 g of an adduct. Here, the isolation yield was 44%.
NMR and IR of the adduct obtained in Example 2
As a result of elementary analysis, it was confirmed that the product was the same adduct A as in Example 1.

(Example 3) In the production method of Example 1, 1,3,3-trimethyl-6'-nitrospiro [2
H-1'-benzopyran-2 ', 2-indoline] and 1-benzyl-3,3-dimethyl-6'-nitrospiro [2H-1'-benzopyran-2', 2-indoline] Was operated in the same manner as in Example 1 to obtain an adduct. Since the adduct was dissolved in carbon tetrachloride, purification was repeated by repeating the operation of dissolving in a small amount of carbon tetrachloride, adding petroleum ether and reprecipitating. 80% isolation yield
Met. NMR of the adduct obtained in Example 3.
A chart is shown in FIG. 3A and an IR chart is shown in FIG.
The results of elemental analysis of this adduct are shown in Table 2 below.
The value shown as “calculated value” in Table 2 is a theoretical value obtained by calculating the composition formula of this adduct as C ₂₉ H ₂₇ N ₃ O ₃ .

Table 2 ——————————————————————— CHN ————————————————————————— −−−−−−−−−−−−−−−−−− Calculated value (%) 74.82 5.85 9.03 Measured value (%) 74.91 5.74 8.86 −−−− −−−−−−−−−−−−−−−−−−−−−−−−−−−−−

From the above results, this adduct is a merocyanine-pyrrole conjugate (B) (hereinafter, referred to as “adduct B”) corresponding to R ＝ CH ₂ -ph (benzyl group) in the above chemical formula 1. That was confirmed.

(2) Decomposition of merocyanine-pyrrole conjugate (a) Decomposition by heat (Example 4) The adduct A obtained in Example 1 was dissolved in deuterated chloroform to obtain a 5% deuterated chloroform solution. This solution was placed in a quartz NMR sample tube and heated at 80 ° C. for 15 minutes. The NMR chart after the heating is shown in FIG. Comparison of FIG. 1B with the standard chart of spiropyran and pyrrole showed that the adduct A was quantitatively decomposed into the original spiropyran and pyrrole by heating. In FIG. 1 (b), the peaks marked with ピ ロ are characteristic peaks of spiropyran, and the peaks marked with ○ are characteristic peaks of pyrrole.

(Example 5) The adduct B obtained in Example 3 was dissolved in deuterated chloroform to prepare a 5% deuterated chloroform solution. This solution was placed in a quartz NMR sample tube and heated to 80 ° C.
For 50 minutes. The NMR chart after heating is shown in FIG. When compared with the standard chart in the same manner as in Example 4, similar to the adduct A, the adduct B
Was quantitatively decomposed into the original spiropyran and pyrrole. In FIG. 3B, the peaks marked with △ are characteristic peaks of spiropyran, and the peaks marked with ○ are characteristic peaks of pyrrole.

(B) Decomposition by ultraviolet light (Example 6) The adduct A obtained in Example 1 and the adduct B obtained in Example 3 were each dissolved in deuterated chloroform to form a 5% deuterated chloroform solution. And Each of these solutions was placed in a quartz NMR sample tube, and a 100 W high-pressure mercury lamp and a color filter “UV-D manufactured by Toshiba Glass Co., Ltd.
Using 35 ", ultraviolet light was irradiated for 10 minutes at a distance of 1 to 2 cm from the sample tube. FIG. 1C shows an NMR chart of the adduct A after irradiation with ultraviolet light, and FIG. 3C shows an NMR chart of the adduct B after irradiation with ultraviolet light. 1C and FIG. 3C were compared with the standard chart as in Example 4. As a result, it was found that both the adduct A and the adduct B were quantitatively decomposed into the original spiropyran and pyrrole by irradiation with ultraviolet light. In addition, even when the ultraviolet light was irradiated for 4 minutes under the above conditions, about half of the adduct A could be decomposed into the original spiropyran and pyrrole.

(C) Decomposition by Acid (Example 7) The adduct A obtained in Example 1 was dissolved in acetone to prepare a 10% acetone solution. 1 in this solution
Upon addition of M hydrochloric acid, a yellow precipitate formed immediately. The yellow precipitate was separated and analyzed by NMR, IR and the like. As a result, it was found that the precipitate was a spiropyran salt, and it was confirmed that the adduct A was decomposed into spiropyran and pyrrole.

(3) Application to Photochromic Pattern Formation Hereinafter, an application example in which the merocyanine-pyrrole conjugate of the present invention is used for forming a photochromic pattern will be described. (Application Example 1) This is an example in which a polystyrene thin film containing the merocyanine-pyrrole conjugate of the present invention is produced, and this thin film is locally heated to form a photochromic pattern. FIG. 5 schematically shows a method of forming a photochromic pattern according to the first application example.

After dissolving 1 part by weight of polystyrene in 10 parts by weight of THF, 0.5 ml of this solution and 0.5 ml of toluene were dissolved.
adduct A obtained in Example 1 in a solution obtained by mixing
Was dissolved in 1 mg. This solution was applied on a transparent polyester film as a substrate by a bar coating method, and then vacuum dried at room temperature for about 120 minutes. As a result, as shown in FIG.
A transparent thin film 10 having a thickness of μm was produced.

[0032] The obtained thin film 10, as shown in FIG. 5 (b), 1 second only heating portion 10a ₁ with a hot stamp, and heated to about 120 ° C.. After this heating step, the heating portion 10a ₁ of the thin film 10 and the non-heated part 10b ₁ is substantially the same color, it was not possible to identify patterns visually. Next, the entire surface of the thin film 10 was irradiated with ultraviolet light for several tens of seconds at a distance of 1 to 2 cm from the thin film 10 using a 6 W UV lamp. By this coloring step, FIG.
(C), the heating section 10a ₂ is colored dark blue purple. On the other hand, the non-heated portion 10b ₂ was slightly bluish and remained substantially colorless and transparent. this is,
Since only adduct A heating portion 10a ₁ in the heating step is to release and degradation spiropyran, this spiropyran by ultraviolet irradiation presumably because a pattern is formed by color dark blue purple. Then, as shown in FIG. 5 (b), by irradiating the visible light (λ> 400nm) to the color of the heating portion 10a ₁ is extinguished. As described above, by alternately irradiating ultraviolet light and visible light, the heating unit 10a
Coloring and decoloring of ₁ could be repeated.

As described above, according to the method of Application Example 1, a photochromic pattern could be formed by local heating. This method is, for example, writing by heat,
It can be used as an information conversion material, an optical recording material, an optical element, or the like read by light.

(Application 2) This is an example in which a photochromic pattern is formed by light energy instead of Application 1 in which a photochromic pattern is formed by local heating. FIG. 6 schematically shows a method of forming a photochromic pattern according to Application Example 2. In the same manner as in the application example 1, as shown in FIG. 6A, a transparent thin film 2 made of polystyrene containing the adduct A and having a thickness of about 1 μm.
0 was made on a polyester film.

[0035] For this film 20, as shown in FIG. 6 (b), the portion excluding the non-irradiated portion 20a _1, using a halogen lamp of 2 kW, the ultraviolet light for 20 minutes from the thin film 20 at a distance of 1m Irradiation was performed as described above. After the ultraviolet light irradiation step, the irradiation portion 20b ₁ of the thin film 20 remained substantially colorless and transparent to the extent that bluish slightly. Next, the thin film 2
The resulting film was left in a dryer heated to about 120 ° C. for 10 minutes. Thus, as shown in FIG. 6 (c), the irradiation unit 20b ₂ were discolored transparent slightly yellowish. No color change was visually observed in the non-irradiated portion 20a ₂ .

The thin film 20 after this heat treatment step has a 6 W U
Ultraviolet light was applied for several tens of seconds from the thin film 20 at a distance of 1 to 2 cm using a V lamp. By this coloring step, FIG.
(D), the non-irradiated portion 20a ₃ was colored in deep blue-purple. In contrast, the color change of the irradiation unit 20b ₃ was observed. This is because the non-irradiated part 2
Since the adducts A of 0a ₂ is released to decompose spiropyran, the spiropyran in color process is thought to have a pattern is formed by color dark blue purple. Moreover, the irradiation unit 20b _2, and adducts A are altered by prolonged intense ultraviolet light irradiation process, it is considered that it becomes impossible to release the spiropyran be heated for this. Then, as shown in FIG. 6 (c) and (d), ultraviolet light, by irradiating alternately visible light, it was possible to repeat the color development and decolorization of the non-irradiated portion 20a _2.

As described above, according to the method of Application Example 2, a photochromic pattern was able to be formed by locally irradiating strong ultraviolet light for a long time and then heating the whole. This method can be used, for example, as an information conversion material, an optical recording material, an optical element, or the like, which is written by light and read out by light after a heat treatment step. Further, according to the application example 2 in which the photochromic pattern is formed by light, it is easier to increase the resolution of the pattern than in application example 1 in which the adduct A is decomposed by heating. There is an advantage that it is easy. Furthermore, according to the method of Application Example 2, the portion irradiated with ultraviolet light for a long time in the ultraviolet light irradiation step does not emit spiropyran even when heated thereafter. For this reason, unlike the application example 1, the pattern is preserved even if decoloring is performed by heating the entire thin film 20 instead of irradiating visible light in FIG. 6D. That is, the advantage that it is possible, as shown in FIG. 6 (c) and (d), by a method of performing alternating heating and irradiation of ultraviolet light, repeating the coloring and decoloring of the non-irradiated portion 20a ₂ is there.

(Application 3) This is an example in which the material of the thin film containing the merocyanine-pyrrole conjugate in Application 1 is changed from polystyrene to polyvinyl acetate. After dissolving 1 part by weight of polyvinyl acetate in 10 parts by weight of ethyl acetate, 0.5 ml of this solution and 0.5 ml of toluene
1 mg of the adduct A obtained in Example 1 was dissolved in a solution obtained by mixing In the same manner as in Application Example 1, this solution is applied on a transparent polyester film as a substrate by a bar coating method, and then vacuum dried at room temperature for about 120 minutes to obtain a transparent thin film having a thickness of about 1 μm. Was. Also for this thin film, a photochromic pattern could be produced by local heating in the same manner as in Application Example 1. here,
Heating unit 10a ₂ in Application Example 1 was colored dark blue-purple, but was colored in dark red purple in applications 3. Also,
Like the application example 2, the method using ultraviolet light was applicable.

The present invention is not limited to the specific examples and application examples described above, but can be variously modified examples and application examples within the scope of the present invention according to the purpose and application. . For example, in Application Example 1, hot stamping is used as a method of local heating, but heating may be performed using laser, infrared rays, or the like. Further, as the material of the polymer matrix thin film containing the merocyanine-pyrrole conjugate of the present invention, a solvent capable of dissolving the merocyanine-pyrrole conjugate of the present invention at room temperature, including the polystyrene and polyvinyl acetate used in the above-mentioned application examples. Any polymer soluble in water can be used without particular limitation.

In the above-mentioned application examples, the case where spiropyran released from the merocyanine-pyrrole conjugate of the present invention is used has been described.
Pyrrole released from the pyrrole conjugate can also be used. For example, by partially heating the thin film containing the merocyanine-pyrrole conjugate of the present invention, pyrrole is generated only in the heating part, and the pyrrole is polymerized by an oxidative polymerization method or the like to obtain a conductive polypyrrole. Thereby, polypyrrole polymerized along the heating pattern is obtained, so that the conductive pattern can be easily formed.

Further, in the above Examples and Application Examples, spiropyran was released by decomposing the merocyanine-pyrrole conjugate of the present invention by light or heat, but it is also possible to decompose it by an acid. A spiropyran salt is directly formed by this method, but this salt also exhibits photochromism, so that a pattern can be formed. The photochromism of this salt is a color change from yellowish to yellowish, but the pattern can be identified by examining the change in spectrum. However, in view of easy identification and easy local treatment, it is preferable to decompose by light or heat, especially when a photochromic pattern is produced.

[0042]

As described above, according to the merocyanine-pyrrole conjugate of the present invention, spiropyran and pyrrole, which can be used as functional materials, are converted by light, heat or acid.
It can be released where needed. Therefore,
By a method such as locally heating the thin film containing this compound or heating the whole surface after local ultraviolet light irradiation, there is no change in appearance, but only the locally heated portion or the ultraviolet light blocking portion, etc. Spiropyran can be produced. Therefore, when this thin film is irradiated with ultraviolet light, only the spiropyran-producing portion develops a color and can be identified as a colored pattern. The color can be erased by irradiation with visible light, and the color can be formed again by irradiation with ultraviolet light, and the color formation and the decoloration can be repeated. This means that the use of the merocyanine-pyrrole conjugate of the present invention provides a novel method for producing a photochromic pattern and can be applied to an information conversion function material or the like in which information is recorded by heat treatment or ultraviolet light treatment and read by light. Is shown.

The merocyanine-pyrrole conjugate of the present invention is also useful as a pyrrole-protecting compound. That is, pyrrole is a volatile liquid at normal temperature, is difficult to handle, and is a compound that is easily oxidized and unstable in the air.According to the merocyanine-pyrrole conjugate of the present invention, pyrrole is used as a solid. Moreover, it can be stored in a state stable to oxidation, and can be taken out by heat, light or acid treatment when necessary. Furthermore, by utilizing this property, pyrrole is released to any specific part,
By polymerizing the released pyrrole, polypyrrole, which is a conductive polymer, can be generated at a specific location.

[Brief description of drawings]

1 (a) is an NMR chart of adduct A obtained in Example 1 in deuterated chloroform, and FIG. 1 (b)
NM after heating this adduct A in deuterated chloroform
It is an R chart, and (c) is an NMR chart after irradiating this adduct A with ultraviolet light in deuterated chloroform.

FIG. 2 is an IR chart of the adduct A obtained in Example 1 by the potassium bromide tablet method.

FIG. 3A is an NMR chart of adduct B obtained in Example 3 in deuterated chloroform, and FIG.
NM after heating this adduct B in deuterated chloroform
It is an R chart, and (c) is an NMR chart after irradiating this adduct B with ultraviolet light in deuterated chloroform.

FIG. 4 is an IR chart of the adduct B obtained in Example 3 by the potassium bromide tablet method.

FIG. 5 is a schematic explanatory view showing a method of forming a photochromic pattern according to application example 1.

FIG. 6 is a schematic explanatory view showing a method of forming a photochromic pattern according to application example 2.

[Explanation of symbols]

10; thin film 10a _1, 10a _2; heating section 10b _1, 10b _2; non-heated part 20; thin _{20a 1, 20a 2, 20a 3} ; unirradiated portions _{20b 1, 20b 2, 20b 3} ; irradiator

Claims (1)

[Claims] 1. A compound represented by the general formula (I) represented by the following chemical formula 1, wherein carbon and pyrrole at the 2-position of merocyanine, which is a ring-opened spiropyran (II) having a nitro group at the 6′-position: A merocyanine-pyrrole conjugate characterized by having a structure chemically bonded to the N-position of Embedded image (In the above general formulas (I) and (II), R is an alkyl group, an aromatic hydrocarbon group or an aromatic hydrocarbon group having an alkylene group interposed, and the aromatic hydrocarbon group is an alkyl group, It can have an aromatic nucleus substituent such as fluorine, chlorine, bromine, an alkoxyl group or an amino group. In the general formula (I), each carbon of the pyrrolyl group and 4 to 4
The carbon at the 7, 3 ', 4', 6 ', α and β positions can have hydrogen, an alkyl group, fluorine, chlorine, or bromine. )