Daicel Chemical Industries, Ltd.

Yoshiyuki Nishida

Hiroshi Takahashi

Masaya Omura

Masanori Hiraishi

Hiroyuki Takemoto

Shuji Nakatsuka

Hiroshi Jinnai

The reflective liquid crystal display device comprises a polarizing plate disposed forwardly of a liquid crystal cell, a relector which is disposed on backside of the liquid crystal cell and reflects an incident light, and a light-scattering sheet which is disposed forwardly of the reflector and scatters the incident light isotopically. The light-scattering sheet can be prepared with the use of a spinodal decomposition method of coating a mixture liquid containing a plurality of polymers varying in refractive index on a transparent support and evaporating or removing a solvent to form a light-scattering layer having a droplet phase structure. The light-scattering layer includes a light-scattering layer showing a maximum intensity of the scattered-light at scattering angles of 3 to 40&deg;, and a light-scattering layer showing maximums intensity of the scattered-light respectively at smaller angles of 2 to 2&deg; and larger angle &thgr;b.

Transmission light-scattering layer sheet and liquid crystal display

A light-scattering sheet having a phase separation structure comprised of a plurality of solid components varying in refractive index is used to construct a liquid crystal display device. In a first embodiment, the light-scattering sheet is disposed in a defined position within a reflecting LCD device. Thus, in a reflecting LCD device comprising a liquid crystal cell constituted of a transparent front electrode plate having a substrate carrying a transparent conductive layer, a back electrode plate having a substrate carrying a conductive layer and a liquid crystal and, as disposed forwardly of the liquid crystal cell, a polarizer, the light-scattering sheet is interposed (i) between the polarizer and the front electrode plate or (ii) between the back electrode plate and a reflector disposed behind the back electrode plate. Alternatively, (iii) the substrate sheet may be constituted of the light-scattering sheet. In a second embodiment, a light-scattering sheet having an isotropic bicontinuous phase structure comprised of a plurality of polymers varying in refractive index is used.

Light scattering sheet, light scattering composite sheet, and liquid crystal display

A light-scattering sheet of the present invention can be produced by applying a liquid mixture comprising polymers varying in refractive index (e.g., cellulose acetate), evaporating a solvent, and forming a bicontinuous phase structure due to spinodal decomposition. In the sheet, incident light can be scattered isotropically, and the transmitted and scattered light may have a maximum intensity of a scattered light at a scattering angle of 2 to 40&deg;. Therefore, the transmitted light can be scattered with high directionality. A reflective liquid crystal display unit has a liquid crystal cell with a liquid crystal sealed therein, a reflector for reflecting incident light disposed behind the liquid crystal cell, a light-scattering sheet disposed forwardly of the reflecting means and a polarizing plate disposed forwardly of the liquid crystal cell. The light-scattering sheet realizes a reflective liquid crystal display unit capable of assuring a high quality image.

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Nagareyama, Japan

Yoshiyuki Nishida