Re: New Gloy = Bakerex

But to expand on Loris's original question, PVA doesn't come in just
one kind. PVA comes in different degrees of hydrolysis, different
degrees of polymerization, different molecular weights. If you
can't specify, your instructions are only of use in a general
nonquantitative sense -- (get some PVA of whatever kind (although the
degree of hydrolysis should be high regardless) some glycerine, some
water; mix them together in proportions of your choosing until it
seems about right)-- because for different PVAs, I would expect that
different amounts of glycerine and water would be needed to reach the
same goal.

BTW, your hydrometer will measure specific gravity but not viscosity;
the two are not highly correlated. (Oh shoot, Gord, I lost the URL
you gave us for this, when I changed computers. But never mind, you
can probably find this information by googling viscosity and specific
gravity.) This is one of the two most useful things I've learned on
this list, the other being why you're not supposed to shift on a curve.

Katharine

On Mar 28, 2006, at 7:32 AM, Loris Medici wrote:

> Ok got it. Thanks.
>
> Regards,
> Loris.
> -----Original Message-----
> From: TERRYAKING@aol.com [mailto:TERRYAKING@aol.com]
> Sent: 28 Mart 2006 Salı 17:26
> To: alt-photo-process-L@usask.ca
> Subject: New Gloy = Bakerex
>
>
> In a message dated 28/3/06 2:22:40 pm, mail@loris.medici.name writes:
>
>
>
>>
>> And my question is. Which type of PVA (or PVAOH) do you use? As
>> far as I
>> can understand, there are different PVA's (or PVAOH's) with different
>> viscosity; I remember reading somewhere that PVA (or PVAOH) used for
>> making glues is PVA (or PVAOH) 25 (25 is the viscosity figure I
>> presume).
>>
>> TIA,
>> Loris.
>>
>>
>
>
> Loris
>
> It's a bit like Scotch, the effect seemes to vary depending how
> much water one puts in it.
>
> ...
Received on Tue Mar 28 09:44:21 2006