MIL-DTL-51523 Dye, Solvent Red 1 \(Metric\)This specification covers two types of Solvent Red 1 dye \(CAS 1229 - 55 - 6\), chemically known as orthomethoxyphenylazobeta-napthol; Type I - for solvent based binders and bowl and V type blenders, Type II - for air based fluidized bed type blenders.