Re: PVA vs. PVA

Hi Katharine,

Something is very wrong with this issue.

Elmer's glue and other European glues that are white and become clear when
they are dried and they are made out of PVA acetate.

I mixed and used the Italian local called "vinavil" and tested also Elmer's
(I had some small amount with me from the US) and they mix with water.

I also bought PVA Alcohol on powder and it mixes with water as well.

Something you are doing is not right.

Giovanni

----- Original Message -----
From: "Katharine Thayer" <kthayer@pacifier.com>
To: <alt-photo-process-l@sask.usask.ca>
Sent: Tuesday, August 02, 2005 4:38 AM
Subject: Re: PVA vs. PVA

> Since no one answered my question about why PVA rather than acrylic, I
> decided to answer it myself and went out to size some papers with (1)
> PVAcetate and (2) acrylic medium, to print with gum and compare. But
> right away I realized I have a problem, because my PVAcetate doesn't mix
> with water; it precipitates out in clumps when mixed with water. Since
> I'm not interested in messing with other solvents, I think this is one
> question I'll just never have an answer to. Such is life,
> Katharine
>
> Giovanni Di Mase wrote:
> >
> > What I am basically working is to produce very large paper prints of
1.00
> > mts x .80 mts using alternative processes.
> > Yesterday I prepared a hand made paper of that dimension and "drunk" 150
cc
> > of PVA acetate sizing at 1:5 ratio (it also gained weight).
> > This was a single sheet of paper.
> > So far my tests with 60 cms x 40 cms prints are fine (I am using Cyano
and
> > Van Dyke so far but I will move afterwards to gum bichromate).
> > I found that PVA acetate sizing for these dimensions and eventually
number
> > of prints is easier than gelatin+hardener sizing but I will only know at
the
> > end.
> > I hope this explanation complies with your WHY question.
> > Giovanni
> > pd No problems producing a large negative and getting the proper UV
source.
> >
> > ----- Original Message -----
> > From: "Judy Seigel" <jseigel@panix.com>
> > To: <alt-photo-process-l@sask.usask.ca>
> > Sent: Monday, August 01, 2005 11:30 PM
> > Subject: Re: PVA vs. PVA
> >
> > >
> > > On Mon, 1 Aug 2005, Giovanni Di Mase wrote:
> > > >
> > > > Any idea what the stock ratio (dilution, pigment and bichromate) and
> > would
> > > > be using glue (any Elmers or Gloy) instead as arabic gum to start
with?
> > >
> > > I'd start with normal gum ratio, which goes anywhere from equal to 1
to 2
> > > to 2 to 1 or more I suppose.
> > >
> > > > I am assuming that Gloy is manufactured out of PVA acetate as all
other
> > > > glues and as I read from Katharine it is not water solubable
therefore
> > could
> > > > not replace the arabic gum, but I have also read the opposite
> > >
> > > If it isn't water soluble when it's dry, obviously you can't make a
gum
> > > print with it, because it won't differentially dissolve. On the other
> > > hand, whatever you're using for a size, has got to be NON-water
soluble,
> > > or it will wash off even as you coat the emulsion.
> > >
> > > > I am going to try anyway and compare to the PVA alcohol glue, I just
> > need to
> > > > have some clear ideas from where I am going to what I can find.
> > >
> > > Well, I think one more thing, though I hope you won't think I'm being
> > > snide... That is, WHY ? I mean, what benefit do you expect from what
are
> > > after all marginal, or anyway minority materials? Which is not to say
> > > there are none (as I recall Joe Smigiel uses rabbitskin glue) but I
have
> > > yet to get an idea from this discussion of what they're supposed to
be. (I
> > > remember, BTW, in fact I have samples in the file, how hard Mike Ware
> > > worked to get decent gradation with PVA. Not to say he didn't
ultimately
> > > get it -- I have no idea -- but that gradation is almost unavoidable
with
> > > a properly coated, exposed, and developed *gum* print.)
> > >
> > > That goes not just for you of course, but for the whole discussion.
> > > What is it about?
> > >
> > > Judy
> > >
>
Received on Fri Aug 5 12:26:35 2005