IPC - Association Connecting Electronics Industries
Scope
INTRODUCTION The acceptance and use of Organic Solderability Preservatives (aSPs) as replacements for Hot Air Solder Leveling (HASL) continues to grow. aSPs selectively protect and maintain the solderability of a PCB's copper features (i.e. SMT pads@ through-holes) by providing thermal protection against degradation during assembly. Historically one class of aSP@ the benzotriazole inhibitors@ has been successfully used by a number of major OEMs in select assembly applications requiring a single heat excursion. During the past five years a new upgraded class of aSP@ the substituted benzimidazole@ has proven to yield additional benefits to PCB fabricators while addressing a diversity of processing challenges encountered by PCB assemblers and OEMs.