Alignment layer composition, alignment layer prepared with the same, preparation method of alignment layer, optical film containing the same, and display device including the optical film

The present invention relates to a liquid crystal alignment layer composition showing excellent adhesive strength to a substrate and a liquid crystal layer and excellent homeotropic alignment of liquid crystals, a liquid crystal alignment layer prepared with the same, a preparation method of the liquid crystal alignment layer, an optical film including the liquid crystal alignment layer, and a display device including the same. According to the present invention, provided are a liquid crystal alignment layer composition which comprises 1-50 wt % of a photocurable resin binder, 0.01-5 wt % of an amine compound selected from the group consisting of primary and secondary amino-based coupling agents, 0.1-5 wt % of a photoinitiator, and the remainder solvent; a method for preparing a liquid crystal alignment layer by coating the substrate with the liquid crystal alignment layer composition, removing the solvent, and curing the liquid crystal alignment layer composition; an alignment layer which is prepared with the liquid crystal alignment layer composition of the present invention; an optical film which comprises the substrate, the alignment layer, and a liquid crystal layer formed on the alignment layer; and a display device including the optical film. The liquid crystal alignment layer formed with the liquid crystal alignment layer composition of the present invention has excellent adhesive strength to the substrate and to an upper liquid crystal layer, and provides excellent homeotropic alignment to liquid crystals. The optical film of the present invention can be applied to a polarizer by itself and can be very helpfully used as a retardation film or a view angle compensation film in various types of LCD modes such as IPS mode and the like.