JPS6211237A - Preparation of organic thin-film crystal - Google Patents

Abstract

PURPOSE:To prepare an organic thin-film crystal onto a high molecular film by using an organic crystal dispersed into the high molecular film as a seed crystal and crystallizing an organic matter in a thin-film manner on the high molecular film. CONSTITUTION:A polystyrene film 3, into which a 2-hydroxy-4- methoxybenzylidene-4'-bromoaniline (MS4BrA) crystallite is dispersed, is formed onto a glass plate 1. 2-hydroxy-4-methoxybenzylidene-4'-butylaniline (MS4BuA) 4 is placed on the film 3, and brought to the state of a liquid crystal through heating. A glass plate 5 is placed onto the substance 4, and cooled and left at rest. Consequently, MS4BuA is crystallized while using the MS4BrA crystallite dispersed into the film 3 as a seed crystal, and a thin-film crystal 6 consisting of MS4BuA is acquired between the film 3 and the glass plate 5. The thin-film crystal is composed of a complete single crystal.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a method for producing organic thin film crystals.

[Prior art and its problems]

Three methods are used to create organic crystals: crystal growth from a gas phase, crystal growth from a solution, and crystal growth from a molten state. These three types of crystal growth methods are described in Maruzen Publishing, New Experimental Chemistry Course, Volume 1, Basic Operations I1.
pp. 639-750. However, the creation of organic thin film crystals has hardly been studied to date, and reports thereof are limited to crystals of polymer compounds. For example, “Journal of the Japanese Society for Crystal Growth, Volume 11,
pp, 117-. 134. 1984 (Comprehensive report by Izumi), examples of polyethylene thin film crystals and polyacetylene thin film crystals are described. The current situation is that no suitable method has yet been developed for producing organic thin film crystals that are not made of polymeric compounds.

[Purpose of the invention]

An object of the present invention is to provide a method for producing organic thin film crystals on a polymer film.

[Structure of the invention]

The method for producing an organic thin film crystal according to the present invention is characterized in that organic crystals dispersed in a polymer film are used as seed crystals, and an organic substance is crystallized on the film in the form of a thin film.

〔Example〕

An embodiment of the present invention will be described with reference to FIG. 1, which shows the manufacturing process. Size 18mrrIX 13mm.

Polystyrene (0.50 g) with a molecular weight of 60,000 and 2-hydroxyl 4-
1 in which methoxybenzylidene-4”-bromoaniline (hereinafter abbreviated as MS4BrA) (0°20g) was dissolved;
4-dioxane (13゜0g) solution 2 at 500Orpm
The film was spin-coated using [Fig. 1(a)]. After drying at 80° C. for 1 hour, a polystyrene film 3 in which MS4BrA microcrystals were dispersed was obtained on the glass plate 1 [Fig. 1 (b)
)). Such a glass plate was placed on a metal melting point block, and 2.0 mg of 2-hydroxy-4-methoxybenzylidene-4°-butylaniline (hereinafter abbreviated as MS4BuA) 4 was placed on the polystyrene film 3 [ Figure 1 (c
)) and heated to 50°C to make it into a liquid crystal state [Figure 1(d)
)]. A glass plate 5 without any coating was placed on top of it [Fig.
Cooled to ℃. When left standing at 32°C for 10 minutes, M S 4 B r dispersed in the polystyrene film 3
MS4BuA is crystallized using A microcrystal as a seed crystal, and MS4BuA is crystallized using A microcrystal as a seed crystal.
A thin film crystal 6 of 4BuA was obtained between the polystyrene film 3 and the glass plate 5 placed thereon [FIG. 1(f)]. This thin film crystal is a perfect single crystal within the field of view of a microscope. The crystal-to-liquid crystal transition temperature of the organic thin film crystal 6 grown on the polystyrene film 3 as described above is 36.5° C., and this thin film turns red when irradiated with 365 nm ultraviolet light.

As a comparative example, a polystyrene film not containing MS4BrA was prepared on a glass plate and an experiment was conducted under the same conditions as in the above example, but no crystallization occurred. This shows that MS4BrA microcrystals are required for crystallization.

In the above example, a thin film crystal of M S 4 Bu A was prepared, but in addition to this, 2-hydroxy-4-methoxybenzylidene-4°-hebutylaniline was also prepared.

Thin film crystals of 2-hydroxy-4-methoxybenzylidene-4°-octylaniline and the like could also be prepared in a similar manner. Further, in the above embodiments, the seed crystals dispersed in the polymer film and the compound that grows to form the thin film crystals are different, but they may be the same compound. Further, the polymer membrane material is not limited to polystyrene, and the coating method is not limited to spin coating, but may also be a casting method, an interfacial film forming method, or the like. Moreover, it does not necessarily have to be fixed on a glass plate. Furthermore, a glass plate placed on top during crystal growth was not necessarily necessary, and thin film crystals could be created without a glass plate. However, in order to obtain a uniform film thickness, it is desirable to have some kind of cover, although it is not limited to a glass plate.

[Effects of the Invention] According to the present invention, an organic thin film crystal can be created on a polymer film by crystallizing an organic substance into a thin film on the film using organic crystals dispersed in the polymer film as seed crystals. You can find a way to do that.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a manufacturing process of an embodiment of the present invention. 1.5...Glass plate 3...Polystyrene film 4...MS4BuA 6...Thin film crystal

Claims (1)

[Claims] (1) Using organic crystals dispersed in a polymer film as seed crystals,
A method for producing an organic thin film crystal, characterized by crystallizing an organic substance into a thin film on the film.