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darvan question

updated fri 8 aug 08

 

Harold Miller on wed 6 aug 08


Question:
What is the relative deflocculating potency of Darvan 7 as compared to
a 40% (wt/vol) solution of sodium salicylate, i.e., how much Darvan 7
would it take to have the same deflocculating effect as, for example,
10 ml of the 40% sodium salicylate?

Thanks.

Harold Miller

John Rodgers on wed 6 aug 08


Harold,

I can't answer your question specifically, but after years of working
with slip casting, I found that I much prefer working with the sodium
silicate as opposed to Darvan. I always found the Darvan to be much to
slow in getting my slip to the point I wanted it. Just a personal
preference. But when I make slip, it's usually 50 gallons at a time and
I want the stuff to deflocculate like right now. But then after making
so much of it over time, I've gotten down pretty pat as to how much to
use in a new batch. As the clay changes over time, with the addition of
scraps etc. I have to vary the amount added, but I still like the
quickness of the deflocculation that occurs with the Sodium Silicate.

John Rodgers
Chelsea, AL

Harold Miller wrote:
> Question:
> What is the relative deflocculating potency of Darvan 7 as compared to
> a 40% (wt/vol) solution of sodium salicylate, i.e., how much Darvan 7
> would it take to have the same deflocculating effect as, for example,
> 10 ml of the 40% sodium salicylate?
>
> Thanks.
>
> Harold Miller
>
>