Re: Dichromate of choice

Judy Seigel (jseigel@panix.com)
Tue, 16 Jul 1996 21:20:15 -0400 (EDT)

On Tue, 16 Jul 1996, Terry King wrote
Judy:
> >.... Terry says sodium dichromate is slower, so don't bother with
> >it. Where did you get that idea, Terry? From reading the Gloy label?

Terry:
> A chemist I know, who did some tests, told me that that was what he found. If
> others have found that the sodium salt gives better results then we all have
> reason to change. In my current catalogues the sodium salt costs twice as much
> as the ammonium.

I haven't noticed, Terry, that you believe everything *I* tell you so
trustingly. Meanwhile we know nothing about how this fella claimed to be
a chemist (tho he obviously wasn't a gum printer) framed his "tests, or
even if he had his glasses on. The thing we do know is that he was wrong.

But who said anything about "better"? I simply said that since sodium
dichromate is more soluble in water, a saturated solution is *faster,* all
other things being equal.

I also said,

> >Since the strength of dichromate is one of the factors in staining in both
> >plain dichromate stain and pigment stain,

To which you replied,
> I have never found that there is a practical difference. In my experience I
> have never had any difficulty with staining.

I never said "problem," Terry, I simply mentioned staining. But since almost
immediately you add (see below) that you never used sodium dichromate I
wonder why you are pressing the issue....

> I have never used the sodium salt but I am not sure that it follows that it will
> stain more.

Wanna bet?

Judy