It is one of the important raw materials for high temperature resistant resins such as polyimide, polyether imide, polyester imide, polymaleimide, polyarylamide, etc. of new special engineering plastics. It is also the raw material for the synthesis of 3,3,4,4 'tetraaminodiphenyl ether, which is the main monomer for the preparation of a series of aromatic heterocyclic heat-resistant polymer materials. It is also used as raw material and crosslinking agent for synthetic polymers such as high-performance heat-resistant epoxy resin and polyurethane. At the same time, it is also used to replace benzidine with carcinogenic effect to produce azo dyes, reactive dyes and spices. At present, direct dyes with different color levels, such as scarlet, bright red, sand red, yellow brown, green, gray, blue, bright orange and black, have been developed with ODA as raw materials. They can be used in the dyeing of silk, wool, cotton, hemp and other fabrics, and their color fastness and exhaustion rate are better than benzidine dyes.