Synthetic resins or natural rubbers -- part of the class 520 ser – Synthetic resins – From carboxylic acid or derivative thereof
Patent
1992-04-21
1994-07-19
Kight, III, John
Synthetic resins or natural rubbers -- part of the class 520 ser
Synthetic resins
From carboxylic acid or derivative thereof
528310, 528322, 5283291, 528331, 528335, 528344, 528348, 428 1, 4284744, 359 75, 359 78, C08G 6926, C08G 6932, C08G 6344
Patent
active
053310810
DESCRIPTION:
BRIEF SUMMARY
The combination of the unusual anisotropic and fluid properties of liquid crystals has, as is known, led to the use of liquid-crystalline materials in a large number of electro-optical switching and display devices. In these, not only the electrical, magnetic and elastic but also the thermal properties of liquid crystals can be utilized to achieve changes in orientation.
Optical effects can be obtained by means of birefringence ("birefringence mode"), the incorporation of dyes ("guest-host mode") or light scattering. For this purpose, until now not only materials having nematic but also smectic liquid crystal phases have been used. Examples of such switching and display devices have already been disclosed in many patents and technical publications.
Liquid crystal switching and display devices have, inter alia the following constituents: support plates (made, for example, of glass or plastic) coated with transparent electrodes and an orientation layer, spacers, adhesive frame, polarizers, and for color displays thin color filter films. Further possible components are antireflection, passivation, compensating and barrier layers and electrical non-linear elements, such as, for example, thin-film transistors (TFT) and metal-insulator-metal (MIM) elements. The detailed construction of liquid crystal displays has already been described in monographies (for example E. Kaneko, "Liquid Crystal TV Displays: Principles and Applications of Liquid Crystal Displays", KTK Scientific Publishers, 1987, pages 12-30 and 163-172).
Of the abovementioned constituents, the orientation layer is of particular importance. As is known, it serves the purpose of ensuring a uniform, undisturbed alignment of the longitudinal axis of the molecules and of a high contrast. It can comprise either organic polymers or inorganic layers.
For many types of liquid crystal displays, in particular, for "supertwist" (STN), "super-birefringence" (SBE), "double-supertwist" (D-STN), "optical mode interference" (OMI) and also ferroelectric (FLC) displays, it is necessary or advantageous that a certain angle, which is called surface-tilt angle, is established between the longitudinal axis of the molecules and the surface of the orientation layer. Depending on the type of design of the abovementioned displays, angles of up to 30.degree. are desirable.
While up to now a large number of orientation layers having a very small surface-tilt angle (0.degree.-3.degree.) have been described, only very few materials are known which lead to an angle of 5.degree. and more.
An example of an orientation layer having a larger surface-tilt angle, which is well-known to those skilled in the art, is silicon monoxide (SiO) vapor-deposited at an angle, which, as is known gives a surface-tilt angle of 20.degree. and at a vapor deposition angle of 7.degree.. However, due to the high cost and the great expense necessary for achieving homogeneity, the vapor deposition process of silicon monoxide is disadvantageous in the case of large areas.
A further example is the use of poly(para-phenylene) as orientation layer. After heat treatment of the material at about 450.degree. C., high surface-tilt angles can be achieved by this process. However, a great disadvantage of this material is the required application of high temperatures during the production process, which stands in the way of using these orientation layers for color LCDs, since the dyes and pigments already begin to decompose above 250.degree. C.
The organic polymer layers used as orientation layers are usually applied to the areas to be coated (for example support plates) in the form of polymer solutions or solutions of soluble polymer precursors by means of processes under pressure, spray-coating, dip-coating or spin-coating processes, and the wet film is then cured--in general by heating it. To achieve an orientation effect, the hard polymer layer obtained is, "rubbed" with a velvet-like coated roll or a roll lined with velvet, a brush or similar devices, thus toughening the polymer surface preferably in a unidirecti
REFERENCES:
patent: 5084557 (1992-01-01), Murata et al.
patent: 5101011 (1992-03-01), Mikami et al.
patent: 5196501 (1993-03-01), Dubal et al.
Dubal Hans-Rolf
Herrmann-Schonherr Otto
Murakami Mikio
Schneller Arnold
Hampton-Hightower P.
Hoechst Aktiengesellschaft
Kight III John
LandOfFree
Use of fluorinated aromatic polyamides as orientation layer for does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Use of fluorinated aromatic polyamides as orientation layer for , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Use of fluorinated aromatic polyamides as orientation layer for will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-520939