METHOD FOR PRIMARY TREATMENT OF WASTE LIQUID FROM PROCESS FOR MANUFACTURING ELECTRONIC CIRCUIT SUBSTRATE

摘要

PURPOSE:To facilitate separation and removal, by reacting an alkaline earth metal salt with a waste liquid generated from a process for manufacturing an electronic circuit substrate and further adding an acid to deactivate the functional group bonded to the terminal part of a photosensitive resin to convert said resin to an insoluble substance. CONSTITUTION:An alkaline earth metal salt such as calcium salt or magnesium salt is added to the waste liquid generated from the developing process and film-stripping process in a process for manufacturing an electronic circuit substrate and reacted with the hydroxyl or carbonate groups bonded to the terminals of a photosensitive resin to bring said group to an active state. Thereafter, an acid such as sulfuric acid or hydrochloric acid is added to said resin and the terminal groups of the photosensitive resin held to the active state are mutually subjected to ion polymerization to convert said resin to an insoluble substance which is, in turn, separated by sedimentation or pressure float separation. By this method, BOD and COD of the waste liquid are lowered and the secondary and third treatments of the waste liquid are facilitated.