Re: PVA for gum printing

Thanks, Martin -- I will give your TAC method a try. What conflicting
statements have you heard about ESTAR?

    Robert Schaller

On 9/7/04 1:39 AM, "MARTINM" <martinm@SoftHome.net> wrote:

> Having read some conflicting statements about its composition, I am not sure
> about Estar. If Estar was similar to PET (polyethylene terephthalate),
> that's to say Mylar, Cronar etc. it would require a great deal of effort to
> coat gelatin or gum on it like: flame/plasma/corona treatment, etching etc.
>
> TAC (triacetate) film is a lot easier to handle: 2 min in a 10% alkali
> hydroxide + (deonized) water rinse will do the job.
>
> Martin
>
>
> ----- Original Message -----
> From: "Robert Schaller" <Robert@RobertSchaller.net>
> To: <alt-photo-process-l@sask.usask.ca>
> Sent: Monday, September 06, 2004 7:35 PM
> Subject: Re: PVA for gum printing
>
>
>> Dear Katherine,
>>
>> I indeed can't see why mylar would introduce any impurities, certainly
>> not water-soluble ones, and wouldn't these be the problem? I also want to
>> applaud your efforts in this, as it seems long overdue that someone
> conduct
>> this investigation in an orderly, scientific fashion. I wish I was set up
>> to do it. I am curious about how the investigation will proceed. What
>> tests exactly is the chemist planning to do? I get the impression that
> just
>> hardened gum (or PVA) will be tested first; what next? As I said, I am
> very
>> curious.
>> Also, on the point of gum on hard surfaces. What about ( and this is
>> probably my question more than yours) getting gum to stick to polyacetate
> or
>> polyester (Kodak's 'Estar') film base? The issue seems related, in that
> it
>> is really asking, how do you get gum to stick to a non-water adhering
>> surface, be it rigid or flexible? I have cheated and used Kodak's already
>> adhered gelatin layer as a subbing layer,as it is already there and is
>> optically transparent, but this avoids the question. Obviously, Kodak et
>> al. know how to get gelatin to adhere -- what's their trick, and would it
>> work as well for gum? Does anyone have any methods, ideas, or
> suggestions?
>>
>> Robert Schaller
>>
>>
>>
>> On 9/4/04 3:32 AM, "Katharine Thayer" <kthayer@pacifier.com> wrote:
>>
>>> Katharine Thayer wrote:
>>>>
>>>
>>>> Do you or anyone know of any reason why mylar shouldn't be used for a
>>>> substrate for hardening the gum?
>>>
>>> No one has answered this question; I take the silence to mean that no
>>> one knows any specific reason to distrust mylar as a substrate. At any
>>> rate, I will wait for the go-ahead from the chemist to be sure, before
>>> finishing the project on mylar. Thanks for suggestions,
>>> Katharine Thayer
>>
Received on Tue Sep 7 16:29:06 2004