To use: In industry, p-toluidine is mainly used as dye intermediate and pharmaceutical pyrimethamine intermediate. As a dye intermediate, used to make red GL, methylamine red lake, basic fuchsin, methylperine acid and 4-amino-toluene-3-sulfonic acid, triphenylmethane dyes and oxazine dyes; It can also be used as the intermediate of medicine pyrimethamine, pesticide, etc. Can also be used as analytical reagents, photometric determination of gold, titanium (ⅲ), tungsten, deposit, silver, osmium, platinum, nitrate, nitrite, phloroglucinol and lignin, determination of carboxylic acid and sulfonic acid, determination of molecular weight solvents.