>
> Think it was Henk in message within a message within a forward who
> mentioned the chemistry that doesn't work in many manuals, bringing to
> mind a number of formulas I've seen that call for gallic acid in
> concentrations from 1% to 10%.
>
> I have reason to believe, however, that gallic acid is only soluble in
> water to about 9/10s percent and my experience of it in some (useless)
> concoctions was that even getting that amount into solution required
> heating, and in a cold room, like as not, it would soon precipitate out
> again.
>
> Alcohol added to the water did better but was hateful when applied to the
> paper.
>
> Any comments? Am I missing something? (I crossed those formulas off
> list, assuming perpetrator unreliable.)
>
> Judy
>
According to Merk, one gram dissolves in 87ml. of water, at 20 degrees
C., but will go into 3 ml. if the water is boiling, so it is very
temperature sensitive. It is, however possible to get more of it into
solution if it is not pure water, in other words after some other
components have already been dissolved.
Would need more specifics to more to give a more specific answer.???