JP2793738B2 - Multifunctional molecular film and dimming control method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a functional molecular film whose optical characteristics are controlled by light irradiation and electrochemical action, and a method of controlling the same, and is applied to an optical information recording medium, an optical computer, a display element and the like. Used.

[0002]

2. Description of the Related Art In order to further reduce the size of conventional electronic devices, research and development of materials focusing on the function of one molecule and attempts to make them into devices have become active. In particular, optical recording, display, and information processing functional devices using photochromic molecules have been considered for use as optical functional devices using light as a signal carrier.

[0003] The state of one molecule can be described by a quantum chemical calculation technique.
The principle of photochromic recording is to leave a trace of the recording as a change in the quantum state by the perturbation of light irradiation.
This reaction can be used for information recording, processing and display using light as a signal carrier.

[0004]

In a wavelength-division multiplex high-density memory using a photochromic reaction, a plurality of wavelengths in the visible light region are converted into the same number of photochromic molecules having different absorption wavelengths existing in the irradiated region. An optical recording method for performing multiplex recording by a light reaction has been considered. At present, an inexpensive multi-color or full-color light source is not available, and it is difficult to reduce the cost of the apparatus when using this method. In addition, since a photochromic molecule has a wavelength region having an absorption wavelength characteristic, it is practically unavoidable that one wavelength reacts with a plurality of types of photochromic molecules having different absorption wavelengths. Therefore, it is difficult to greatly improve the recording density.

In a spatial light modulator used for projection display and optical information processing, a dimming function of a photochromic material has attracted attention. The photoreaction can perform information processing that enables parallel addressing of optical information without using a highly coherent light source such as a laser. is there. However, since the photoreaction is a linear phenomenon in principle as shown in the definition of the quantum efficiency of the reaction, there is a problem that the recorded content is destroyed by the reproduction light when reading the recorded information. This is one of the causes of significantly narrowing the application range of the light control function film to the information processing element.

In order to solve these problems, it is necessary that the photochromic reaction can be controlled by perturbations other than light (for example, heat, electricity, hydrogen ions, gas molecules, etc.). It is more desirable to be able to control the reaction. However, so far, no material has been found that meets these requirements.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and has a structural formula (Formula 2).

[0008]

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It is an object of the present invention to solve the above-mentioned problem by using a photochromic material comprising a crosslinked spiropyran represented by the formula (1) as one of the film components and utilizing a new dimming characteristic control method.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings.

(1) Synthesis of 3-chloromethyl-5-nitrosalicylic aldehyde (Compound 1) In order to crosslink a photochromic molecule and an electrochromic molecule using the reactivity of a chloromethyl group in the following reaction formula (Formula 3), Starting material (3-chloromethyl-5-nitrosalicylaldehyde, compound 1 in the reaction scheme)
) Is shown.

For the synthesis, known references (L. Taylor and R. B. Davis, Journal of Organic Chemistry, 28, 1713, 1963)
Year). The reaction product was recrystallized from carbon tetrachloride to obtain a light brown compound 1 with a yield of 58%. Melting point was 89 ° C. as measured by DSC.

[0013]

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(2) Synthesis of Compound 2 The following reaction formula (Formula 4) shows the synthesis route of Compound 2. The starting material used here, 1-octadecyl-2-methylene-3,3'-dimethylindoline, is described in the literature (I.
Gulda and Earl. M. LeBlanc, Journal of
Canadian Chemistry, 54, 576, 1976
Year). In the synthesis, 4,4'-bipyridyl and Compound 1 were refluxed in benzene to obtain Compound 2 as a yellow-orange solid.

[0015]

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(3) Synthesis of crosslinked spiropyran (compound 3) The reaction formula of crosslinked spiropyran (compound 3), which is the final target substance from compound 2 and 4,4'-dipyridyl, is shown in (Chemical Formula 5). In the reaction, the two compounds were dissolved in ethanol and refluxed to obtain a crosslinked spiropyran (Compound 3). Recrystallization from ethanol was performed, but the crystallinity of the sample was poor.
Compound 3 was in a deep purple oily state, but could be obtained as a black solid by slowly removing the ethanol solvent over 5 months or more. A glass transition temperature of 136 ° C. was observed by DSC measurement. Final yield was 10%.

[0017]

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(4) Preparation of Multifunctional Molecular Film The molecular film is prepared by diluting arachidic acid with a functional molecule in an equimolar amount and accumulating it on a glass substrate provided with a single-sided transparent conductive film (indium tin oxide) by the LB method. I got it. The manufacturing conditions are as follows.

Number of layers: 10 layers, surface pressure: 20 mN / m, pH of water tank: 6.5, water temperature: 18 ° C. (5) Evaluation of multifunctional molecular film FIG. It is an apparatus figure of a chemical measurement. The electrodes were composed of a transparent electrode 9 and a gold wire electrode 2. 5 W% aqueous potassium chloride solution 3 as supporting electrolyte
Was used. For the measurement of absorbance, a commercially available spectrophotometer (MPCD-2000 manufactured by Otsuka Electronics Co., Ltd.) was used.

FIG. 2 is a diagram summarizing the results of the photochromic reaction and the electrochromic reaction. Upon irradiation with ultraviolet light (365 nm), the molecular film changed from spectrum 12 to spectrum 11, and changed from a non-colored state to a colored state. Thereafter, a wavelength of 570 n is applied to the colored film.
When the laser beam of m was irradiated, the state returned to the non-colored state 12.

When the gold electrode 2 is applied with a positive voltage of 1.8 V to the transparent electrode 9 in the colored state 11, the uncolored state 1 is obtained.
Returned to 2. From the above, it was found that the photochromic reaction can be controlled by the electrode reaction.

The molecular film of the present invention is not limited to the LB film, but can be applied to a cast film and a spin coat film.

[0023]

As described above, the multifunctional molecular film of the present invention is not only a photochromic reaction which changes between a non-colored state and a colored state by light as in the prior art, but also a non-colored state by electrons. It also has the property of an electrochromic reaction that changes between colored states. This indicates that the photochromic reaction can be controlled by the electrode reaction. By combining the photochromic reaction with another photochromic material, a low-cost, wavelength-multiplexed high-density memory without crosstalk can be realized.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram of an apparatus for evaluating optical and electrochemical characteristics of a molecular film.

FIG. 2 shows a visible absorption spectrum of an uncolored film and a visible absorption spectrum of a colored film.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 Multifunctional molecular film 2 1 mmφ gold electrode wire 3 5 W% KCl aqueous solution 4 Low voltage application power supply 5 Irradiation optical fiber 6 Light receiving optical fiber 7, 8 Lens 9 ITO (indium tin oxide) electrode 10 Glass substrate 11 Colored state 12 Absorption spectrum of the film in the visible region 12 Absorption spectrum of the film in the uncolored state

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ identification code FI G11B 7/24 516 G11B 7/24 516 (58) Field surveyed (Int.Cl. ⁶ , DB name) C09K 9/02 G02F 1 / 17 G03C 1/685 G03C 1/72 G09F 9/30 G11B 7/24 REGISTRY (STN)

Claims (2)

(57) [Claims] 1. One of the membrane components has a structural formula (Formula 1) Multifunctional molecular film characterized by using a photochromic material represented by 2. A method for controlling light control characteristics of the multifunctional molecular film according to claim 1, wherein the light control characteristics are controlled by an electrode reaction.