JP2844508B2 - Photoresponsive composition containing calixarene derivative - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composition containing a calixarene derivative, and more particularly to a photoresponsive film composition which can be used as an erasable / writable optical recording material.

[0002]

2. Description of the Related Art CD-ROM about 10 years ago
Since the emergence of the optical recording system, the write-once type (WOR
M: Write Once Read Many) or erase / write type (E
Research and development on optical recording materials for DRAW (Erasable Direct Read After Write) are being actively conducted.

Most of the materials conventionally used as optical recording materials are inorganic, and even when organic materials are used, they are merely auxiliary. However, inorganic materials inherently have limitations in recording density, resolution, and the like, and no EDRAW-type recording materials based on inorganic materials exist. Thus, it is expected that organic recording materials can theoretically become erasable / writable optical recording materials with high density and high resolution.

Many studies on erasing / writing type optical recording materials using organic materials utilize photochromism. Photochromism is a phenomenon in which a change in the colored state of a compound, A → B and B → A, occurs reversibly by light, and A → B light and B →
The light A has different wavelengths. At this time, B →
The problem is that the change A is caused by heat.
In order for a photochromic organic compound to be usable as an erasing / writing type recording material, 1) erasing / writing by light irradiation
The compound must be stable even if writing is repeated. 2) It is necessary that the compound does not thermally return from B to A. Many photochromic compounds are known, but no compound that sufficiently satisfies these conditions has been found.

For example, an organic compound represented by the following formula (Formula 1) is colored by XeCl excimer laser light and decolored by Xe lamp light, and shows considerable stability against repeated irradiation of these lights. It is reported that a reaction due to heat under dark conditions is likely to occur.

[0006]

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[0007] As another example, a photochromism system utilizing the fact that the photodimerization reaction of two anthracene groups (bianthracene) is reversibly generated and extinguished by irradiation of ultraviolet light and visible light is more often seen than before. Few thermally stable systems have been found, and in particular, no specific technology has been established as an erasable / writable optical recording material.

[0008]

SUMMARY OF THE INVENTION The present invention provides a novel organic recording (memory) which is stable even after repeated erasing / writing by light irradiation and which does not cause an undesired reverse reaction even in the dark. The purpose is to obtain the material.

[0009]

Means for Solving the Problems and Effects of the Invention The above-mentioned object is achieved according to the present invention by a composition containing a specific calixarene derivative. That is, the present invention provides a method for preparing a calix [4] arene derivative in which the 25-position and the 27-position or the 26-position and the 28-position are substituted with a 9-anthryloxy-ethyl group and a sodium salt. It is a photoresponsive film composition mixed with a polymer containing an agent.

[0010] Calixarene is a cyclic oligomer in which a plurality of phenol units are linked by a methylene group, and exhibits a unique property as an element for recognizing atoms and molecules. Attention has been paid. The present inventor has realized a material that can be used as an erasable / writable optical memory based on the facts found in the course of research on the recognition function of various calixarenes for metal atoms. Established technology.

The calixarene derivative used in the present invention is a calixarene having four phenolic units, that is, the 25- of the calix [4] arene molecule.
Positions and 27-position (or 26-position and 28-position) are 9-anthryloxy-ethyl groups (9-anthryloxy-eth
yl) is a kind of bianthracene-containing compound substituted with yl), but for easy understanding, it can be represented by the following formula [Chemical Formula 2] when represented by a general structural formula.

[0012]

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In the calixarene, the side having the phenolic OH group is located at the lower or lower edge (lower ri).
m), the opposite side is often referred to as the upper rim. In the present invention, the calixarene derivative is prepared at every other position of the lower edge OH group (that is, 25-position and 27-position, or 26-position and 28-position).
It is important that the 9-anthryloxy-ethyl group represented by Z in [Chemical Formula 2] is present, and other groups cannot achieve the desired effect. For example, —O—
Instead of CH ₂ —CH ₂ —, —CH ₂ —O—CO—CH ₂
When-, stable photodimerization as described below does not occur.

As X and Y (Y ₁ , Y ₂ ) in the calixarene derivative represented by the above formula [Formula 2], various types of calixarene derivatives conventionally used in calixarene derivatives are used unless the object of the present invention is impaired. Groups or functional groups are possible. X is preferably a group such that the entire calix [4] arene molecule easily adopts a cone structure as a conformation. Preferred X
Examples of —C _n H _{2n + 1} [n is an integer of 2 or more, preferably an integer of 2 to 5], and — (CH ₂ CH ₂
O) _m CH ₂ CH ₃ [m is an integer of 1 or more, preferably an integer of 1 to 4] or —CH ₂ CO ₂ CH ₂
CH ₃ is mentioned. Y ₁ and Y ₂ are generally the same, but may be different. Y ₁ and Y ₂ are considered to be related to the affinity with the plasticizer. Preferred examples of Y ₁ or Y ₂ are —H, —C (CH ₃ ) ₃ [t-butyl group], or —C (CH ₃ ) ₂ C (CH ₃ ) ₃ [t-octyl group].

When the above-mentioned calixarene derivative of the formula [Formula 2] is dissolved in a suitable solvent or supported on a suitable carrier and irradiated with light having a wavelength of 350 nm or more,
As shown in FIG. 1, the calixarene derivative undergoes photodimerization to change from A to B, and the color changes from yellow (A) to transparent (B) accordingly. When the calixarene derivative (B) in which the anthracene portion is photodimerized is irradiated with light of 280 nm or less, the state returns to A again. However, the calixarene derivative cannot be used as a stable recording medium because the reverse reaction (thermal change) of B → A occurs even when light is not irradiated. The present inventor has found that if a predetermined amount of sodium salt is added to a calixarene derivative and is present in a plasticizer-containing polymer, a thermal reverse reaction does not occur and the film is stable against repeated light irradiation. They have found that the composition is a formable composition, and have conceived of using this composition as an erasable / writable optical recording material.

Thus, the sodium salt used in the present invention is excellent in photostability under light irradiation, and has high solubility in a carrier polymer and can form a transparent film. Preferred sodium salts include, for example, NaCl
O ₄ and NaBF ₆ . In addition, CH ₃ CO
Sodium salts of organic acids such as ONa can also be used. When PVC (polyvinyl chloride) is used as the polymer, NaClO ₄ is preferable, and NaSCN or NaCl
Sodium salts such as Cl are not preferred in terms of photostability and solubility in polymers.

In order to obtain a photoresponsive composition which is stable to repeated light irradiation and does not cause a thermal reverse reaction according to the present invention, the quantitative ratio of the sodium salt to the calixarene derivative is extremely important. The molar ratio of the / calixarene derivative is 10 or more, preferably 20 or more. On the other hand, if the amount of the sodium salt is too large, the precipitation of the sodium salt in the plasticizer is not preferable. Therefore,
The molar ratio of sodium salt / calixarene is NaC
40 or less in the case of an inorganic salt such as lO _4, CH ₃ COON
In the case of an organic acid salt such as a, the content is preferably 100 or less.

The present invention provides a solid composition which can be applied as an optical recording material to be an erasable / writable memory by combining a calixarene derivative / sodium salt represented by the following formula [2] and a polymer containing a plasticizer. Membrane composition). The polymer used must have good solubility in sodium salts and high stability to light irradiation. Examples of preferred polymers are PVC (polyvinyl chloride), PEG (polyethylene glycol), PVA (polyvinyl alcohol), PP
G (polypropylene glycol), PMMA (polymethyl methacrylate) and the like, and PVC is particularly preferred. Further, the plasticizer needs to have high compatibility with the polymer and excellent optical properties. That is, the plasticizer is selected from those that are inert to light irradiation and have absorption characteristics that do not overlap the absorption band of anthracene. Furthermore, the plasticizer must be highly compatible with the sodium salt used and provide a transparent film composition with relatively low rigidity. Examples of preferred plasticizers are linear dicarboxylic acid-based plasticizers such as TEP [tri (2-ethylexyl) phosphate] or DES [di (2-ethylexyl) sebacate].
The relative amount of the polymer and the plasticizer can vary depending on the desired mechanical properties when the film composition of the present invention is prepared and used as an optical recording material, but generally, the relative amount is based on 1 part by weight of the polymer. , 1 to 3 parts by weight, preferably 1.5 to 2.5 parts by weight of plasticizer.

The calixarene derivative used in the present invention can be prepared according to a synthetic route as shown in FIG. The preparation method in each step is roughly as follows:
It looks like this:

I) Preparation of compound (1) [9- (2-bromoethoxy) anthracene]: Anthracene, sodium hydroxide and 18-crown-6 are dissolved in 1,2-dibromoether and water, and the mixture is dissolved at 25 ° C. for 3 hours. After stirring for days, the organic layer is separated and the solvent is removed. The residue was chloroform /
Recrystallization in hexane gives compound (1).

Ii) Preparation of compound (2): A tetrahydroxycalix [4] arene derivative as a starting material is
The bromo reagent (BrX) and potassium carbonate are added in acetone and reacted at 75 ° C. for 1-4 days. After removing the solvent, the solid is washed with dilute hydrochloric acid and water. Compound (2) is obtained by recrystallization in chloroform / hexane.

Iii) Preparation of compound (3): compound (1)
And (2) were dissolved in THF with NaH,
The reaction is carried out at a temperature of 1 to 3 days under a nitrogen atmosphere. After cooling the mixture, methanol is added to quench the NaH and the solvent is removed. When the obtained solid is purified using a silica gel column, compound (3) is obtained.

In order to obtain a film-like composition suitable for producing an optical memory according to the present invention, the calixarene derivative, sodium salt, polymer and its plasticizer obtained as described above are mixed with a suitable solvent. The solvent may be removed from the homogeneously dissolved mixture. At this time, it is preferable that the calixarene derivative is blended in an amount of 0.10 to 1.50% by weight based on the entire system consisting of the calixarene derivative / sodium salt / polymer / plasticizer.

The film thus obtained can be used as an optical recording (memory) element together with a suitable support. For example, the film of the present invention (for example, having a thickness of 0.15 m)
m) is supported on both sides by quartz glass (for example, 0.5 mm in thickness), one side is irradiated with a light beam for information read-in, and the other side is read-out information.
Connect visible / ultraviolet light detection device for t).

The film composition of the present invention exhibits excellent photoresponsiveness, and changes its coloring state by irradiation with visible light of 350 nm or more, and returns to its original state by irradiation of ultraviolet light of 280 nm or less. repeat. This property does not substantially change by repeated irradiation of visible light / ultraviolet light, and does not cause a thermal reverse reaction even when ultraviolet light is not irradiated after irradiation with visible light. Therefore, the film composition of the present invention can provide an organic optical recording system in which information can be written / erased using visible light / ultraviolet light.

In a recording system using the composition of the present invention, a state change accompanying irradiation of visible light / ultraviolet light can be detected as electric conductivity or membrane potential. Therefore, the reading of information may be performed by measuring such a physical quantity, and the optical recording material according to the present invention has advantages not found in conventional simple organic compounds.

Hereinafter, the present invention will be described with reference to Examples to further clarify the features of the present invention.

[0028]

EXAMPLES Example 1 Preparation of a Calixarene Derivative Preparation of 9- (2-bromoethoxy) anthracene: 1 containing anthrone (25.0 g), dicyclohexano-18-crown-6 (0.70 g). 300 ml of a 2,2-dibromoethane solution and sodium hydroxide (2
5.0 g) and stirred for 3 days at room temperature under a nitrogen atmosphere. The organic layer was separated and 1N HCl (50 ml ×
3) After washing with water (50 ml × 4), anhydrous MgSO
Dried at ₄ . After removing the solvent under reduced pressure, the obtained yellow solid was recrystallized in a mixed solvent of hexane / chloroform to obtain yellow crystals of 9- (2-bromoethoxy) anthracene. 28.6 g (73.8% yield);
１127 ° C .; mass spectrum (EI) m / e301 (M
⁺ ); Elemental analysis C 63.97, H 4.39 (calculated C
63.81, H4.35).

[0029]5,11,17,23-tetra-t-buty
-25,27-dihydroxy-26,28-bis
(2-ethoxyethoxy) calix [4] arene
Preparation:5, 11, 17, 23 shown as the following [Formula 3]
-Tetra-t-butyl-25,26,27,28-tet
Lahydroxycalix [4] arene (25.0
g), K_TwoCO_Three(32.0 g), and 2-bromoethyl
Ru-ethyl ether (50.0 g) was added to 300 ml of acetone.
The solution obtained by dissolving in
For 4 days. After removing the solvent under reduced pressure, the residual
The product was extracted with chloroform (50 ml × 3). Obtained
Chloroform solution with 1N HCl (50 ml × 3)
After washing with water (50 ml × 4), anhydrous MgSO_FourDry
did. The solvent was removed under reduced pressure, and the resulting white solid
And recrystallized in chloroform / chloroform.
To give the desired compound. 15.61 g (yield 58.
4%); melting point 167-168 ° C; mass spectrum (E
I) m / e792 (M⁺); Elemental analysis C 78.54, H
9.16 (calculated C78.74, H9.15).

[0030]

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[0031]

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[0032]5,11,17,23-tetra-t-buty
-25,27-bis (2-ethoxyethoxy) -2
6,28- [2- (9-anthryloxy) ethoxy]
Preparation of calix [4] arene:Get as above
9- (2-bromoethoxy) anthracene (1
0.0g), the compound (1.00 g)
And NaH (1.0 g) dissolved in 50 ml of THF.
The solution was placed in a dark atmosphere at reflux temperature for 5 days.
After heating and reacting under the temperature, the mixture was cooled to room temperature. Residual N
Methanol was added to quench aH. solvent
After evaporating off the residue, 300 ml of chloroform was added to the residue.
And 1N HCl (50 ml × 3) and water (5
0 ml × 4) and then dried over anhydrous MgSO_FourDry in
Was. The yellow solid obtained by removing the solvent under reduced pressure was silica gel
Chromatography (eluent hexane /
(3: 1 mixed solvent of chloroform).
To obtain the desired calix [4] arene derivative represented by
Was. 0.34 g (21.8% yield); mp 177-17
8 ° C., mass spectrum (SIMS) m / e1233 (M
⁺), 1256 ([M + Na]⁺); Elemental analysis C81.9
1, H 7.95 (calculated C 81.78, H 7.84).

[0033]

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Example 2: Preparation of membrane composition 50 mg of PVC, 100 mg of plasticizer, calix [4] arene derivative of Chemical Formula 5 prepared in Example 1 0.90
mg and NaClO ₄ 0 to about 4 mg in THF 3.0.
The resulting solution was poured into a flat Petri dish (3.0 cm diameter). The solvent was slowly evaporated at room temperature under a nitrogen atmosphere with the Petri dish in the dark to give an elastic film (about 0.1 mm thick).

Example 3 Photoresponse test In order to examine the applicability of the film prepared in Example 2 as an optical recording material, the photoresponsiveness was tested. The test was performed in Example 2.
Was cut into a size of 1.0 × 2.5 cm ² , and a small piece obtained was placed in a removable quartz cell. Light irradiation is with a filter (MIF-UW: λ ₀ = 381 nm)
Or λ ₀ = 279 nm) high-pressure mercury lamp (450
W).

The rate of the thermal reverse reaction : When a beam of 381 nm was irradiated using the above mercury lamp, the yellowish film turned transparent (corresponding to AB in FIG. 1). If left as it is, the colored state of the film gradually returns to the original state (corresponding to B → A in FIG. 1). This change in B → A was examined quantitatively by following the change in absorbance at 372 nm (λ _max ). FIG. 3 shows that D is used as a plasticizer for PVC.
When ES [di (2-ethylhexyl) sebacate] is used, the molar ratio of the sodium salt NaClO ₄ to the calixarene derivative of the formula [NaClO ₄ ] / [NaClO ₄ ] /
[C. A. ] Shows how the first-order reaction rate constant k of B → A changes. In the absence of NaClO ₄ , the rate constant is about 5 × 10 ⁻³ / min, indicating a half-life of about 140 minutes, making it unsuitable for use as an optical recording material.

However, the present inventor has surprisingly found that the presence of the sodium salt (NaClO ₄ )
It was discovered that the reverse reaction of A was significantly suppressed. That is, as shown in FIG. 3, [NaClO ₄ ] / [C.
A. ] Increases, the rate constant k decreases, the reverse reaction is gradually suppressed, and [NaClO ₄ ] /
[C. A. ] ≧ 10, k became substantially zero, and it was confirmed that the reverse reaction was completely suppressed.

Light irradiation cycle test : Next, 279 nm
And 381 nm, alternately irradiating 372 nm
The difference in absorbance at nm was measured. The sample used for the test contains DES as a plasticizer as in the case described above. First, 381 nm is irradiated for 20 minutes, and then 279 nm for 1 minute per cycle.
Irradiation at 381 nm for 5 minutes was repeated.

The results are shown in FIG. 4 and FIG. FIG.
Is a sodium salt (NaClO ₄ ) used for comparison
In the case of no addition, it can be seen that the absorbance difference disappeared by repeating the light irradiation for 8 cycles, and the photostability was lacking.

On the other hand, [NaClO ₄ ] / [C.
A. ] = 20, a slight change in absorbance difference was observed in the initial few cycles, as shown in FIG.
Thereafter, even if light irradiation is repeated, there is no significant change in the absorbance difference. FIG. 5 shows the results up to 20 cycles. Even if the same light irradiation was repeated for 100 cycles or more, there was no substantial change, and approximately 80% of the initial absorbance difference was maintained. It was confirmed that a film having high light stability suitable as an optical recording material was obtained by the addition.

The effect of several plasticizers on the cycle test was examined in comparison with the case where no sodium salt was added. The results are shown in Table 1 below.

[0042]

[Table 1]

The numbers shown in the table are the number of cycles at which the difference in absorbance at 372 nm can maintain the original 80%. When TEP [tri (2-ethylhexyl) phosphate] and DES [di (2-ethylhexyl) sebacate] are used, a film having extremely excellent light stability can be obtained. In these cases, the transparency of the film is very high. D
When BE (cibenzyl ether) or BDD [bis (1-butylpentyl) decane-1,10-diyldiglutarate] was used, a cloudy film was obtained. NPO
The poor photostability of E (O-nitrophenyloctyl ether) is thought to be due to the undesirable photochemical side reaction caused by the nitrobenzene moiety.

[Brief description of the drawings]

FIG. 1 schematically shows a photochromic reaction generated by a calixarene derivative used in the present invention.

FIG. 2 is a flowchart outlining a method for synthesizing a calixarene derivative used in the present invention.

FIG. 3 is a graph showing a change in a rate constant of a thermal reverse reaction in a film composition according to the present invention.

FIG. 4 is a graph showing data for a film composition containing no sodium salt as a comparison to show the photostability of the film composition according to the present invention.

FIG. 5 is a graph showing the light stability of a film composition according to the present invention.

Claims (1)

(57) [Claims] 1. The 25-position and 27-position or 26
The calix [4] arene derivative substituted at the -position and the 28-position with a 9-anthryloxy-ethyl group and a sodium salt are adjusted so that the molar ratio of sodium salt / calix [4] arene derivative is 10 or more. And a photoresponsive film composition mixed with a polymer containing a plasticizer.