SOLUTION FOR CLARIFICATION OF COAT OF TIN-LEAD ALLOY ON PRINTED CIRCUIT BOARDS Russian patent published in 1994 - IPC

FIELD: electronics. SUBSTANCE: solution has following proportion of components, g/l: ethylene-diamin of tietraethanoic acid 5-50, 2-oxi=1.3 propylenddiamin-tetramethylenephosphoric acid-tetra-sodium salt 2-50; sodium hydroxide 5-20, washing powder 0.5-5.0, white spirit 0.3-5.0; water being the balance. EFFECT: reduced time of clarification, exclusion of mechanical cleaning, enhanced labour intensity, improved working conditions, increased reliability of printed circuit boards die to cancellation of use of chlorine. 1 tbl