Abstract: An improved process for the manufacture of sodium metabisulfite is provided. In this process, the chemical reaction forming sodium bisulfite solution is carried out separately from the crystallization of sodium metabisulfite. The crystallization step is carried out without chemical alteration and without pH adjustment.

Abstract: Piperazine containing positive photoresist stripping compositions are provided. Formulations include N-aminoalkylpiperazines with the formula ##STR1## bis-N-aminoalkylpiperazines of the formula ##STR2## N-hydroxyalkylpiperazine of the formula ##STR3## and bis-hydroxyalkypiperazines with structure ##STR4## In the above formulae n=1-6. Also included are piperazine derivatives such as those of the above formulae with a branch chain alkyl of 1-6 C atoms, and 5-6 atom cycloalkyl substituted compounds wherein the cycloalkyl is substituted for --(CH.sub.2).sub.n --. Components which may be mixed with the above described piperazine in preparing the positive photoresist stripping compositions of the invention include alkyl or cycloalkyl-2-pyrrolidones of the formula ##STR5## Other amide type solvents with the boiling point in excess of 200.degree. C. as well as high boiling diethylene glycol ethers may also be incorporated.