Archive of the former Yahoo!Groups mailing list: Homebrew PCBs
Subject: HP technical pen ink does not work for etching
From: Rob <roomberg@...>
Date: 2016-11-22
Not sure if the dating on this make a difference......
I bought HEWLETT PACKARD
Disposable Liquid-Ink drafting Pens
.5mm Medium Point HP Part no 5061-7620
says For use on paper or vellum only on the package
and drew on copper .5 mm traces.
The ink looked very wet so I did two passes and let it dry on a heater vent.
Then.... etched in peroxide and muriatic acid.
All the black traces looked intact until the very last etching copper disappeared
BUT
one swipe with a light touch makeup brush simple wiped away the black traces to reveal ZERO
copper under the ink traces.
The package said USE BEFORE JAN 1992 so perhaps I would get a different result from
TODAYs inks instead of using 25 year old ink. Who knows if they even use the same chemistry now.
But for paper.... these are really nice pens.