JPS61169838A - Reversible organic optical memory material and its production - Google Patents

Abstract

PURPOSE:To increase the optical response speed and to improve the repeating reproducibility and the shelf stability of a record by dispersing a clathrate compound consisting of a specified anthracene deriv. and gamma-cyclodextrin in a resin binder. CONSTITUTION:An anthracene deriv. represented by the formula (where R is a hydrophilic substituent) and gamma-cyclodextrin are dissolved in an aqueous medium to form a clathrate compound, and light is irradiated to dimerize the anthracene deriv. in the clathrate compound. A resin binder is dissolved in the soln. and formed into a film, and the dimer of the anthracene deriv. in the clathrate compound dispersed in the resin film is depolymerized by irradiating light on the resin film or heating the film. Thus,a reversible org. optical memory material showing photochromism by a reversible photodimerization reaction in the resin binder is obtd. The optical memory material has a satisfactory optical response property and superior reversibility in the writing of information and gives a record with superior shelf stability and processability. It is used as an optical information storing or recording material.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a reversible organic photomemory material and a method for producing the same. More specifically, the present invention incorporates one-element information using an inclusion compound of an anthracene anchor conductor and r-cyclodextrin, which exhibits photochromism due to a reversible photodimerization reaction as a photochromic compound. The present invention relates to an organic memory material exhibiting reversible photoresponsiveness that allows repeated reading and erasing, and a method for manufacturing the same with full efficiency.

Conventional technology photochromic! ? Many organic compounds have been studied so far, and many memory materials using them have also been proposed (1986-14948).
(No. 9, Japanese Unexamined Patent Publication No. 58-37078) However, organic photochromic compounds have many problems such as slow reaction rate, lack of repeatability and storage stability of records.

The original memory material using this material, Fit, has not been put to practical use.

By the way, in recent years, photochromism based on a reversible photodimerization reaction has been attracting attention as it can be applied to memories with particularly excellent storage stability ([Appl, Opt.
J Vol. 11, p. 533, 1972).

In order to put it into practical use, it has been proposed that, for example, two molecules of a linearly condensed ring aromatic compound are linked with a cyclophane-type covalent bond to increase the reaction rate (``Tetrahedron Letters''). Tstrahedron Letts, )
J, IN vol. 23, p. 197, 1982)
.

Only 1. Therefore, such cyclophane-type compounds generally have K due to distortion of the ring of the formed dimer.

Disadvantages such as ring-opening polymerization easily occurring in reverse reaction, and molecular design that relaxes this strain slows down the reverse reaction rateft
Therefore, it cannot be said to be practically satisfactory.

Problems to be Solved by the Invention Under these circumstances, the purpose of the present invention is to provide an organic optical memory which has extremely excellent one-dimensional response speed, repeatability, and storage stability, and which can be easily used in practice. The material is to provide pipes.

Means for Solving the Problems The present inventors have previously found that r-cyclodextrin has the effect of significantly promoting the photodimerization reaction of anthracene conductor in an aqueous solution, and has developed a combination of potassium 2-anthracene sulfonate and potassium 2-anthracene sulfonate. r-Cyclodextrin forms a stable clathrate compound with a guest:phos) ratio of 2:1 by simply mixing and dissolving it in water, and by irradiating this solution with monochromatic light of an appropriate wavelength, Anthracene-type reversible trimerization reactions occur extremely efficiently, and associated reversible photochromism has been observed.

The present inventors focused on the properties of such an inclusion compound of anthracene fermentation conductor and r-cyclodextrin, and
Further research has shown that even by dispersing this clathrate compound in a binder resin, it can achieve reversible photochromism with a fast response rate just like in an aqueous solution, and that the clathrate compound The compound prevents fatal photo-oxidation reactions due to r-cyclotextrin's excellent protective effect against oxygen, which also improves the cyclic stability of photochromism and the storage stability of the material. thing,
Therefore, it has been found that the above object can be achieved by dispersing the clathrate compound having such properties in a pipe binder resin.

Based on this knowledge, we have completed the present invention.

That is, 5 the present invention provides a reversible organic light comprising a clathrate compound of an anthracene impurant and r-cyclotextrin represented by the general formula (in which Ri is a hydrophilic substituent) dispersed in a binder resin. A memory material, anthracene represented by the general formula (11) and γ-cyclotextrin are dissolved in an aqueous medium.

After forming these clathrate compounds, this is irradiated with a source to dimerize the anthracene derivative in the clathrate compounds, and then a binder resin is dissolved in this solution.
This can be coated if desired.

Further, by irradiating this resin film with a source or heating the cough resin film, the dimer of the anthracene derivative in the clathrate compound dispersed in the resin film is depolymerized. The anthracene derivative used in the present invention provides a method for producing organic optical memory materials.

It has a hydrophilic substituent represented by the above-mentioned formula (1), and examples of this substituent include a sulfonic acid group or its weir, a carboxyl group or its in situ, an amine group, etc. , and specific examples of the anthracene derivatives include 2-anthracene sulfonic acid or in situ,
Examples include 2-anthracenecarboxylic acid or a salt thereof, 2-aminoanthracene, and the like.

These anthracene derivatives are easily soluble in water (and upon single-element irradiation, they form dimers that are degradable adducts (r 4+4 ), and this dimer can be converted to the original form by irradiation or heating of short pseudomorphic elements. The anthracene derivative has the property of being restored to a monomer.

When in contact with r-cyclotextrin in an aqueous solution, the 1L anthracene core moiety, leaving its substituents in the aqueous phase, enters the cavity of the cyclodextrin to form a stable clathrate. The stability of the clathrate compound used in the present invention is much greater than that of the clathrate substituted at the 1-position.On the other hand, the 9-position compound has greater steric hindrance due to the substituent, and is therefore encapsulated in cyclodextrin. Not touched.

In the present invention, as cyclotextrin that forms an inclusion compound with the anthracene derivative.

An r type is used. By simply mixing and dissolving this γ-cyclotextrin together with the anthracene derivative in an aqueous medium, the guest: host-2:
Forms a clathrate compound of 1. On the other hand, α- and β-cyclodextrins do not have such an inclusion ability because they both have a small nine-antrum radius.

By irradiating an aqueous solution containing the clathrate compound of r-cyclotextrin and the anthracene derivative, a dimer, which is a [4+4] amylated adduct of the anthracene 94, is produced with poor efficiency. . The rate of reaction at this time is about 10 times faster than when the cyclodextrin is not present. This is a steric configuration in which the aromatic surfaces of 94 anthracene molecules, which are clathrated within the cavity of one molecule of cyclodextrin, overlap in a sandwich shape that is convenient for the addition reaction to occur. ′? -It is thought to be for taking.

The dimeric anthracene derivative produced by such light irradiation also forms a stable inclusion compound with r-cyclodextrin, and this dimer remains clathrated with γ-cyclodextrin and is converted into a short modified compound. The original monomer is decomposed by irradiation.

What is noteworthy is that the highly efficient and reverse reactions of anthracene derivatives within the cavity of this solid r-cyclotextrin occur in exactly the same way in the 41g fat matrix as in aqueous solution. 1 The present invention has been made by taking advantage of such properties.

In the present invention, the binder resin used to constitute the one-component memory material (for example, polyvinyl alcohol, polyvinylpyrrolidone, polyacrylic acid, polymethacrylic acid, polyacrylamide, polyoxyethylene, water-soluble nylon, water-soluble polyurethane, etc.) Water-soluble resins are preferably mentioned. These resins may be used alone or in combination of 2a1 or more.

Next, one example of a preferred method for producing the base memory material of the present invention will be described. First, the required amount of anthracene derivative and r-cyclodextrin are added to an aqueous medium for 20 to 20 minutes.
A temperature of 30°C 1 Usually melts at room temperature, and their inclusion f
After forming a compound sound, this solution is irradiated with a source with a wavelength of 350 to 400 nm using, for example, a xenon lamp, and 94 anthracenes in the commercially available clathrate compound are irradiated with 2TF. and r-cyclotextrin in a 5 molar ratio of 1:1 to 1:20.
It is preferable to use γ-cyclotextrin in an amount of 0.5 to 3 parts by weight per 100 parts by weight of the aqueous medium. Then into the solution.

At least one selected from the above resins is used as a binder resin, and the amount is 50 to 20% per 100 parts by weight of the clathrate compound.
After adding 0 parts by weight and dissolving the solution, the original memory material of the present invention can be obtained by coating this solution on a support layer such as a quartz glass plate to form a film. If necessary, a hydrophobic resin such as butyral resin, acrylic resin, or vinylidene chloride resin may be used to form an S-retaining film. In the present invention, furthermore, it can be obtained in this manner as desired. A resin film in which a clathrate compound of anthracene dimer and r-cyclotextrin is dispersed is irradiated with a short wavelength light of 270 to 290 nm, or the resin film is heated to a temperature of 150°C or higher. The dimer may be depolymerized and converted into a monomeric clathrate by heating at .

What is important in such a manufacturing process is to use a dimeric clathrate compound as the clathrate compound when dispersing it in a binder resin. this is.

When using monomer clathrate compounds, some of the monomers are converted from γ-cyclotextrin molecules to resin? This is because the solution leaks into the FF solution, making it difficult to obtain a good original memory material. Such a phenomenon does not occur with a dimeric clathrate compound, and the dimer is uniformly dispersed in the resin while being clathrated with γ-cyclotextrin molecules. This is the difference between monomers and dimers.

This is thought to be due to differences in stability of the clathrate compounds due to differences in polarity as compounds and differences in structural bulkiness.

In this way, once dispersed in the resin film as a dimeric clathrate, the monomer generated by short-length element irradiation will be transferred from the γ-cyclodextrin molecules into the resin matrix, unlike in a solution. To fI! It exists stably as an inclusion compound without being released.

By the way, when only the dimer is dispersed in the resin without adding r-cyclotextrin, no reversible interconversion of the monomer and dimer is observed. However, the monomers generated by the dissociation of dimers by short-wavelength light irradiation move to energetically stable positions, deviate from the configuration favorable for dimer formation, and form dimers again. This is thought to be because it becomes impossible. Dimers cannot be generated even if the monomer is dispersed from the beginning ◇On the other hand, when the guest molecule is included in r-cyclotextrin, the free movement of the guest molecule is restricted. Then, a reversible original reaction proceeds.

The inclusion effect of γ-cyclodextrin in the present invention includes not only the high efficiency ratio of such a reversible photodimerization reaction but also the excellent anti-oxidant effect against oxygen. When oxygen is present in the reaction system of anthracene derivatives, a photooxidation reaction easily occurs, irreversibly producing peroxides and quinones. Therefore, suppressing this photooxidation reaction is extremely important in improving the repeatability of the photochromics reaction, which is the ftJ dimerization reaction. The anthracene derivative clathrated with r-cyclodextrin in the present invention does not undergo photooxidation and only a reversible photodimerization reaction proceeds, making it possible to realize repeated reproducibility of the photochromics reaction in an air atmosphere. 0 In addition, in the present invention, as described above, the depolymerization from dimer to monomer can be carried out using 15
It can also be caused by heating to temperatures above 0°C. At this time, 1. Normally, the formation of colored substances may be observed, but r
- Its production can be significantly suppressed by the presence of cyclotextrin. Therefore, it is also possible to perform a reversible photochromics reaction using a reverse reaction by heating. Moreover, the cleavage of the dimer due to heating
The fact that this occurs only at temperatures much higher than room temperature is advantageous from the viewpoint of the thermal stability of the original memory material and the storage stability of the record.

The original memory material obtained in this way is converted into information by interconversion at the molecular level between the dimer of the anthracene derivative clathrated with r-cyclotextrin in the resin film and the it form. Input.

It can be read and erased. Reversible interconversion between dimer and monomer can be achieved by choosing the wavelength of the irradiated light. In other words, the absorption region of the monomer of anthracene derivatives is generally on the longer wavelength side than that of the dimer, so by irradiating + $ at a wavelength that only the body absorbs, the monomer is converted into the dimer. The reaction can be carried out selectively, by irradiating the element at the wavelength where the absorption of the monomer is relatively small.
It is possible to preferentially cause the reaction from dimer to monomer. Since monomers are thermodynamically more stable than dimers, the reaction from dimer to monomer can occur even by heating. High selectivity of reaction over reaction 〇 The memory information stored as such interconversion between dimer and monomer can be read out as a change in absorbance or refractive index. In order to read out changes in absorbance, it is applied to the measurement source gold resin film, which has a weaker pattern than the writing irradiation light or irradiation beam.

The transmitted light or the reflected source? 0 can also be done by detecting with an original electron amplifier tube. When reading by changing the oil contact ratio, there are no particular restrictions on the wavelength, but it is preferable to use light with a longer wavelength than the wavelength absorbed by the monomer.

Effects of the Invention The reversible organic photomemory material of the present invention exhibits photochromic gold as a photochromic compound in a binder resin through a reversible mole ratio reaction.

It is a dispersion of an clathrate compound of anthracene conductor and γ-cyclotextrin, which has excellent properties such as one-way response, reversibility of information writing, record preservation, and processability. Since it is 7F4, it is useful as a storage and recording material for one-dimensional information.

Examples Is the invention explained by examples? 0 Example 1 Potassium 2-anthracenesulfonate 12q and r-cyclotextrin-Hibori Misaki? Dissolved in water lO− in a Pyrex eggplant flask and heated under a sow xenon lamp for 30 min.
The irradiation source, which was irradiated for 0 minutes, was passed through a Corning 3-73 filter and a water phase for heat isolation. Next, the obtained reaction solution was dried using yLM to obtain a colorless powder. High performance liquid chromatography and unexpected absorption spectra revealed that a dimer was quantitatively produced in this product.

After dissolving this dry powder 50 Misaki in 1 dK of water, polyvinyl alcohol 40 JII? The resin was added and dissolved to obtain a photochromic resin liquid. This solution was placed on a quartz glass plate at 110
Spin coating was performed at 00 rpm. Evaluation of photoresponsiveness of the obtained photochromic resin film? , 2, the irradiation elemental degree t'l using a %V xenon lamp as a light source (JASCO-CRMFA
) and then measuring the change in the absorption spectrum for 1 minute. the result.

The absorption spectrum of the resin film as adjusted is only that of the dimer in the short wavelength customary region of 300 nm.

It became clear that the absorption of the monomer in the 300-400 nm region was unreliable. In other words, first 280 soil 10n
Upon irradiation with monochromatic light of 380 nm, the appearance of absorption of the monomer was observed.Next, upon irradiation with 380 nm and 10 nm, the absorption of this monomer was observed to disappear.9. In the process of dimer → monomer, the quantum yield is 1.0 to 0.1 for monomer production.
．． In addition, in the monomer-dimer process, the decrease in monomer was 0.8±0.1, which is close to the theoretical maximum value of 2.00.

The repeatability of one cycle of dimer → monomer → dimer showed over 95 sounds. Furthermore, even after the resin film used here was stored in the dark for one month, the exact same light It showed responsiveness. The attached drawing is an absorption spectrum diagram of the resin film obtained in this way at room temperature, and shows
(2) and (2) are the results after the original tube was irradiated with wavelengths corresponding to the upward and downward arrows, respectively, in this order.

Example 2 91. Example 1 except that 2-anthracenecarboxylic acid was used instead of potassium 2-anthracenesulfonate. When the photoresponsiveness was evaluated in the same manner as in Example 1, similar results were obtained.Example 3 A resin film was formed on a quartz glass plate in the same manner as in Example 1, and then this resin was Film '1170tl: was heated for 5 minutes to create an optical memory material in which a clathrate compound of 2-anthracene sulfonium/IIIJium monomer was dispersed in the film. 〇 Regarding this material, Example 1 When the photoresponsiveness was evaluated in the same manner as above, it was found that upon irradiation with 38 G±l Onm, the absorption of the monomer disappeared and the absorption of the dimer appeared.
Then, upon irradiation with monochromatic light of 280±10 nm, absorption of the monomer was observed. Regarding the quantum yield, similar results were obtained in Example 1&ll. Comparative Example 2 - Potassium anthracene sulfonate 15WIgi water 1
After dissolving 0sgtc, the same procedure as in Example 1 was carried out.

Light irradiation was performed for 2 hours. Next is this reaction solution? Lyophilization gave a pale yellow powder. As a result of the analysis, it was confirmed that 60% dimer was produced. 3 q of this dry powder was mixed with 1 -
After dissolving polyvinyl alcohol 409 therein, this resin liquid was applied on a quartz glass plate in the same manner as in Example 1 to form a resin membrane tube. When this product was evaluated for photoresponsiveness, almost no reversible interconversion between monomer and dimer was observed.

[Brief explanation of the drawing]

The drawing is an absorption spectrum diagram of a resin film obtained in an example.

Claims (1)

[Claims] 1 A binder resin containing an clathrate compound of an anthracene derivative and γ-cyclodextrin represented by the general formula ▲ Numerical formula, chemical formula, table, etc. ▼ (R in the formula is a hydrophilic substituent) A reversible organic optical memory material dispersed in 2 The anthracene derivative represented by the general formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (R in the formula is a hydrophilic substituent) and γ-cyclodextrin are dissolved in an aqueous medium, and their inclusion The method is characterized by forming a compound, irradiating the compound with light to dimerize the anthracene derivative in the clathrate compound, dissolving a binder resin in this solution, and then forming a film from this compound. A method for producing reversible optical memory materials. 3 The anthracene derivative represented by the general formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ (R in the formula is a hydrophilic substituent) and γ-cyclodextrin are dissolved in an aqueous medium and their inclusion After forming a compound, it is irradiated with light to dimerize the anthracene derivative in the clathrate compound, and then a binder resin is dissolved in this solution to form a film, and the resin film thus obtained is A reversible organic optical memory material characterized in that a dimer of an anthracene derivative in the clathrate compound dispersed in the resin film is depolymerized by irradiating the resin film with light or heating the resin film. manufacturing method.