[Table of Contents] [Search]


[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: Etching copper type



The proper type of ferric chloride for photogravure is refered to as "acid
free".  The material is made by disolving scrape iron in sulphuric acid and
then precipitating the ferric chloride sludge from the saturated solution.
The technical or industrial grade (which is much cheaper) isn't quite the
same quaility because their is still too much free acid in the mix. The
process is based upon the scheduled and predictable break down of the
gelatin resist.  The cheap stuff dosen't work as well for a full contrast
photographic image,  However a drawing on mylar contract printed may work ok.
I think I've used 30 gallon units of 42 balume Hunt Chemical Blue Label
Ferric Chloride in the past. I used to full range of the standard
dilutions. I always use the cheap stuff (what you have) for photoetching
and save the Blue Label for gravure.
Does that help?

I have several photogravure books...who's information are you looking at?


At 06:09 PM 3/2/98 -0600, you wrote:
>On Thu, 26 Feb 1998 10:52:29 -0800 Michael Morin
>> I always use liquid technical grade which is far cheaper than any
>reagent grade >from a school lab supply.
>
>Michael or anyone else on the list,
>What is the difference? I bought some 42 Baume ferric chloride from an
>Engraving supply house (cheap!) and have been wondering what grade this
>may be and whether there should be any particular concerns with using
>this to etch copper for photogravure. I'm asking about etching concers--I
>already am familiar with the health and safety issues. BTW, I will be
>using various dilutions to etch--I need to do trade with a friend for a
>more saturated solution.
>
>Thanks,
>David
>
>_____________________________________________________________________
>You don't need to buy Internet access to use free Internet e-mail.
>Get completely free e-mail from Juno at http://www.juno.com
>Or call Juno at (800) 654-JUNO [654-5866]
>


[Subject index] [Index for current month] [Table of Contents] [Search]