Liquid crystal compound, liquid crystal composition, polymer and application thereof

Abstract

The invention a liquid crystal compound, a liquid crystal composition and a polymer and application which can suppress refractive index anisotropism due to wave lengths, display low wavelength dispersion characteristics and further display inverse wavelength dispersion. The invention discloses the compound expressed by the formula (1) and the liquid crystal composition containing the compound.

Description

technical field [0001] The invention relates to a liquid crystal compound having a benzothiophene, benzofuran or indole structure, a liquid crystal composition, a polymer and applications thereof. Background technique [0002] In recent years, liquid crystal compounds having a polymerizable group have been utilized in optically anisotropic films showing birefringence (optical anisotropy), such as reflective polarizers and retardation plates. This compound exhibits birefringence in a liquid crystal state, and by polymerization, its orientation is fixed. The fixed orientation state of the polymer includes homogeneous (horizontal orientation), tilt (tilt orientation), homeotropic (vertical orientation), and twist (twisted orientation). [0003] Optically anisotropic films with parallel orientation can be used as composite retardation plates, circular polarizing plates, for example, by combining with 1 / 2 wavelength plates, 1 / 4 wavelength plates, or films with other optical func...

AI Technical Summary

Problems solved by technology

On the other hand, in liquid crystal displays (Liquid Crystal Display, LCD) and other display devices, the light source is white light including light with a wavelength of about 380nm-800nm, but when designing 1 / 2λ or When a 1 / 4λ plate or the like is used in combination, the following problems arise due to the above-mentioned wavelength dispersion: a change in the polarization state due to the wavelength occurs, and the light becomes colored

However, such a laminate has the following problems: two retardation layers are required, and the angle of anisotropy of the two retardation layers needs to be adjusted, etc., the complexity of manufacturing for forming the laminate, and the optical parameters The film thickness of the anisotropic layer becomes thicker, etc.

[0011] However, since the compound described in Patent Document 6 has low refractive index anisotropy, it is necessary to increase the film thickness in order to obtain a desired retardation, and there are also concerns about the following problems: it is difficult to control the orientation uniformity due to the small aspect ratio, and further, Difficult to manufacture due to long synthesis path, etc.

The compounds described in Patent Document 7 and Patent Document 8 have absorption in the visible region, so they tend to cause a decrease in transmittance or color spots, and are not suitable for use in optical applications.

The compounds described in Patent Document 9 and Patent Document 10 are relatively good in terms of optical properties and production processes, but further improvement in properties is required in terms of mechanical strength of the polymer, adhesion to the substrate, heat resistance, etc.

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