Study On The Process Of Oriented Liquid Crystal Light Oriented Materials And Its Oriented Layer

LCD has become the dominant display device in human’s life and has been applied everywhere so far. However, as the mobilization of consumer electronic deepening and the concept of Internet of things emerging, people cannot be satisfied by current display devices any more. Many new directions have been proposed, such as super HD display, flexible display,3D display etc. As flexible display stands out for its lightness, thinness and flexibility, it has become a very expected and promising direction.However, flexible LCD mainly use plastic and fiber as substrates, which makes it impossible for traditional processes to fit. Especially for the align-ment process that directly decides the display mode of LCD. In traditional alignment process, polyimide is cured under high temperature, and addition-al friction is applied afterwards to fabricate micro grooves on the alignment layer to induce liquid crystal molecules to align in a same direction. But plas-tic substrates cannot endure such high temperature. A new method must substitute the traditional ones to enable the production of flexible display.Photo alignment draws a wide attention as it shows a solution for this problem. It not only eliminates the high-temperature process, but also pro-vide many advantages, such as non-contact alignment and multi-domain alignment etc. To accomplish the alignment on flexible LCD, this issue u-tilizes the photo alignment method. A polymer material of coumarin was synthesised. This material undergoes anisotropic cross-linking upon the il-lumination of polarized UV light and formate polymer lines along a same direction which can induce LC molecules’alignment. Fabrication of photo-alignment layer using this material can be accomplished under room tem-perature in the whole process without curing. This material provides a very good effect. ECB mode LC cell with such photo-alignment layer performed a dense and uniform dark state. Transmittance under the dark state can be as low as less than1.5%. Comparison of the synthesised material with polyimide and a quasi-commercial photo-alignment material shows that their dark state under ECB mode LC cell were of the same quality. Although there was room for elevation on stability comparing to latter two materials, this material still has a bright future in application due to its good alignment effect. It did provide a practicable solution for flexible LCD alignment problem.