Dear Chin-Jen Chiang
I think that protek is better than black wax for koh wet
etching protection.

Giancarlo Canavese

Department of mechanics
Politecnico di Torino
C.so Duca degli Abruzzi 24
10129 Turin (ITALY)
Tel. +39-011-5646969  Fax. +39-011-5646999
Tel. +39-011-9114899  Fax. +39-011-9136490
Cell. +39-338-4400661
e-mail: [email protected];
http://www.polito.it/micronanotech
http://www.latemar.polito.it
--------------------------------------------------