Method for producing orientation layers for liquid crystal displays and liquid crystal displays having orientation layers

Claim 1

In a method for producing orientation layers for liquid crystal displays wherein a solution of an organic prepolymer is applied to a transparent substrate and subsequently annealed and subjected to an orientation treatment, the improvement comprising employing as said solution of an organic prepolymer, a solution of a prepolymer of a polyoxazole, a volatile compound and a solvent, and rubbing after annealing without photolyzing or irradiating before annealing as the orientation treatment, to produce a homogeneous orientation layer which will exhibit essentially no change in morphological structure up to a temperature of about 46° C., which shows essentially little intrinsic color when the layer thickness is at least about 0.1 μm, and which, after annealing, is reduced in thickness up to about forty percent compared with its thickness before annealing as a result of volatilization of the volatile compound during annealing, wherein the polyoxazole prepolymer has the formula: ##STR12## R being an at least partially aromatic or heterocyclic, halogenated or non-halogenated, tetravalent group; R 1 being a divalent, halogenated or non-halogenated aliphatic, cycloaliphatic, aromatic, or heterocyclic group; R 2 being an alkyl group which is free from an olefin substituent; and n being an integral number from 2 to about 100; and wherein said volatile compound is a monomer, oligomer, polymer or mixture thereof which evaporates at least in part at a temperature above 250° C.