contacting the polyimide surface with {HEAD ~ an aqueous solution} of {TAIL ~ nitric acid} having a concentration of about 35 to about 70% by weight or an aqueous solution of hydrochloric acid having a concentration of about 10 to about 38% by weight 
contacting the polyimide surface with { HEAD ~ an aqueous solution } of { TAIL ~ nitric acid } having a concentration of about 35 to about 70 % by weight or an aqueous solution of hydrochloric acid having a concentration of about 10 to about 38 % by weight
OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH