Cresyl Violet perchlorate, also known as oxazine 9, is a laser dye. Cresyl violet is a small diaminobenzooxazine with a moderately sized planar conjugated system. Application： Among its many applications, Cresyl Violet can be used to stain for Nissl substance and nuclei in nervous tissue and the identification of Helicobacter. Cresyl Violet perchlorate has been used to make cresyl violet perchlorate-polymer composite thin films. It also has been used as a fluorescence standard.