- Synonyms: Aurin, 4-[Bis(4-hydroxyphenyl)methylene]2,5-cyclohexadien-1-oner- C19H14O3r- M = 290,32 g/molr- CAS [603-45-2]r- EINECS-No.: 210-041-8r- Solub. in water: (20 ºC): 1,2 g/lr- GHS-signal word: Warningr- GHS-H sentences: H315 - H319 - H335r- GHS-P sentences: P261 - P280 - P305+P351+P338 - P321 - P405 - P501ar- Tariff number: 3212 90 90 00r- Applications: microscopy, manufacture of dyes.rrSPECIFICATIONSrpH range (yellow-red): 6,8 - 8,0 rAbsorption maximum l (in ethanol + 2 ml HCl 1N): 482 - 486 nmrAbsorptivity (A1%/1 cm; l max.): > 1250 rinsoluble in C2H5OH : passes testrcopper (Cu): max. 0,005 %riron (Fe): max. 0,005 %rlead (Pb): max. 0,005 %rnickel (Ni): max. 0,005 %rresidue on ignition (as SO4): max. 0,5 % rloss on drying (110 ºC, 1h): max. 10 %r