Re: Using Gluteraldahyde; was: Glutaraldahyde activation?

Chris an Clay,

My bottle of MACO Geladur-LP (which is the same as Black Magic hardener
as confirmed by Maco) contains only 2-5% glut which I read as something
between 2 and 5 percent. The safety sheet mentions the same percentages
too. For black magic they advise to make a working solution of 5 ml in
100ml water. Per liter black magic or gelatin they advise to use 20-50ml
of this working solution (i.e. 1.0-2.5ml of the concentrate).

I used Geladur again last week by adding 3ml of the concentrate to 500ml
of warm 3% gelatin. This was the first time I used this 'direct'
hardening method. I'm hardening normally in a separate bath (15ml
glyoxal in 1 liter water) with a rinse afterwards. These geladur
hardened results were not good. The paper behaved if unsized, cleared
very slowly in the water and stained. There were also coating streaks
visible on the paper I coated with a brush.

In earlier tests, also reported on this list, I hardened with geladur in
a separate bath and these papers printed fine. This leaves two
conclusions possible: the 'direct' method doesn't work for me or the
geladur has gone bad since then. I'll try the separate hardening method
again this week.

kees

Christina Z. Anderson wrote:

> Clay,
> Just got my shipment of Black Magic in this past week (not for use
> with gum, but with liquid emulsion for the class I am teaching, but if
> I have some left over I will test). I notice on the side panel it
> says if I read it correctly 15-20% glut, and it is to be diluted.
>
> Whether the sulfite has an effect on the sizing remains to be seen,
> but considering I have sulfur here in my water anyway, I can't imagine
> the miniscule amount in the sizing I am mixing is going to have a
> serious effect. But that is an uneducated guess.
> Chris
> ----- Original Message ----- From: "Clay" <wcharmon@wt.net>
> To: <alt-photo-process-l@sask.usask.ca>
> Sent: Friday, September 30, 2005 9:34 PM
> Subject: Re: Using Gluteraldahyde; was: Glutaraldahyde activation?
>
>
>> Anybody using black magic hardener for the glut source? What amounts
>> per 1000ml of gelatin?
>
>
>
Received on Mon Oct 3 02:54:55 2005