After etching, the workpieces are washed with a mainly neutral washing liquid consisting of {HEAD ~ a solution} of the salt required for regeneration of {TAIL ~ the etching agent} 
After etching , the workpieces are washed with a mainly neutral washing liquid consisting of { HEAD ~ a solution } of the salt required for regeneration of { TAIL ~ the etching agent }
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL