N-​[4-​[[3,​4-​bis(sulfomethyl)​phenyl]​[4-​(diethylamino)​phenyl]​methylene]​-​2,​5-​cyclohexadien-​1-​ylidene]​-​N-​ethyl-​Ethanaminium Inner Salt Potassium Salt

N-​[4-​[[3,​4-​bis(sulfomethyl)​phenyl]​[4-​(diethylamino)​phenyl]​methylene]​-​2,​5-​cyclohexadien-​1-​ylidene]​-​N-​ethyl-​Ethanaminium inner salt potassium salt is an organic dye used in the preparation of negative-working heat-sensitive lithographic printing plate precursors.