Re: glutaraldehyde

Ryuji Suzuki wrote:
>
> From: Katharine Thayer <kthayer@pacifier.com>
> Subject: Re: glutaraldehyde
> Date: Wed, 17 Mar 2004 09:53:30 +0000
>
> > This makes a great deal of sense. Thanks,
> > kt
>
> No it doesn't, at all. I recommend you to read the material I mailed
> you again.

Ryujii,
I assume you mean the Burness and Pouradier chapter from James on
gelatin hardening, since the other two articles you sent me are about
other things. I've read that chapter quite thoroughly and I see nothing
in Tom's comments that is incompatible with the information it contains;
he seems to agree with B&P that the glutaraldehyde provides better
crosslinking, but questions whether there may be such a thing as too
much crosslinking. This question makes sense to me. I appreciate your
input, but I do my own thinking, and I get to decide what makes sense to
me and what doesn't.

At the moment I'm experimenting with hardening gum arabic, for a purpose
related not to gum printing but to painting; I'll explain after the
glutaraldehyde comes and I have more complete results to report. But
preliminary results are that at the strengths I've tried, chrome alum
doesn't harden the gum enough and glyoxal hardens it perhaps too much,
as it has a grainy, sugary appearance on the surface of the hardened
gum. I'm already at the smallest amount of glyoxal that I can measure (1
drop) so next I will try 1 drop in more gum, to see if I can get the
insolubility without the graininess. And I've got a sample drying that
has a higher proportion of chrome alum, to see if more chrome alum will
harden the gum. So I'm still testing; I don't have any firm conclusions
yet. But given what I've seen so far, the possibility that there might
be such a thing as more crosslinking than we need makes eminent sense to
me.

As to his speculation about potential damage to the print, it seems to
me that your statement that there is no possibility that it will damage
the print is as much speculation as his speculation that it might.

Katharine Thayer
Received on Wed Mar 17 18:15:51 2004