If oil will be absorbed into the soap, would glycerin?

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gigisiguenza

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I was playing with an idea in my head and I'm curious about the way things are absorbed into the soap as it sets up (after pouring, but before unmolding and cutting).

I know that if you grease the sides of your molds with any fat (Pam, oil, lard, etc) it will be saponified and sort of glue your loaf to your mold. And I know that the reason mica swirls work is because the soap will absorb and saponify the oil the mica is suspended in.

Would the same principle work with glycerin? If I wanted to suspend a colorant in glycerin and use it for a swirl (like the mica swirl), would the soap absorb it the way it does the oils? Or would it cause a problem?

TIA :)
 
if I'm not mistaken, saponification process produces glycerin? theoretically, excess glycerin wouldn't be absorbed, correct?
 
Some people do premix their colours in to glycerin. If I recall, they make it strong and then add it to batter so it dilutes and then use the batter for swirls, rather than adding it directly. But I can't be certain as I don't do it

I've done that TEG, and it works very well. That's why I wondered if it could be used for a swirl on top, like some do with micas and oils. But I think it may just float on top, having considered what was commented earlier. Would hate to waste the effort on it if it's most likely not going to work. I'm determined to try this idea but I'm working out the quirks :)
 
That's an interesting thought. I too have seen it done with the oil/mica mixture, but can't think of any time I've seen a glycerine/mica mixture used for drizzle.

I want to try it with mica and with a natural colorant and see if I can get a bleed effect, but I'm trying to think how to do it. Pardon the smoke, it happens when I'm thinking hard LOL
 
Just because glycerin is produced in making soap, that does not exclude the possibility of the soap absorbing some. However, I would worry about it remaining sticky or prolonging the cure time. But there is only one way to know for sure, right?
 
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Just because glycerin is produced in making soap, that does not exclude the possibility of the soap absorbing some. However, I would worry about it remaining sticky or prolonging the cure time.

The cure time I'm willing to wait for, but if it never fully absorbed and made for permanently sticky soap, that's a no bueno.
 
Now you've got me thinking - which is dangerous.
Glycerin is one of the products of saponification so if I try this with a lower SF recipe would the glycerin "stay put" and not soften the soap too much?
I may want to see how oil and glycerin mix before I ran a batch though. It may work quite well as a carrier mixed into some batter though.

I do know that if you add glycerin and sugar to lye soap that a solvent - usually alcohol is used - which results in a LOT of shrinkage during cure.
 
I have done mica/glycerin drizzles on the tops of HP and the glycerin did absorb, leaving just the shimmery mica behind. It wasn't sticky at all, but I didn't use a lot.

ETA: Here is a pic of an HP soap where I worked the mica/glycerin mixture into the top inch or so of soap. After the first week of curing, it wasn't sticky at all.

forum.jpg
 
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Now you've got me thinking - which is dangerous.
Glycerin is one of the products of saponification so if I try this with a lower SF recipe would the glycerin "stay put" and not soften the soap too much?
I may want to see how oil and glycerin mix before I ran a batch though. It may work quite well as a carrier mixed into some batter though.

I do know that if you add glycerin and sugar to lye soap that a solvent - usually alcohol is used - which results in a LOT of shrinkage during cure.

Thinking is only dangerous when you don't do it at all. :)
 
I've used mica mixed with glycerin. I've drizzled this syrup in pencil lines to add gold flecks simulating "gold ore". I've also used it on top of a loaf to add decorative accents of gold. The lesson I've learned (the hard way, of course!) is to not be heavy handed with the glycerin-mica syrup. Thin drizzles and small droplets are fine. Big droplets of the syrup may not be absorbed by the soap.

When I've over drizzled within a pencil line, the excess glycerin may weep out of that area over time, leaving small cavities behind. When I've over drizzled on top of a loaf, the excess glycerin may leave a sticky spot. Sometimes the sticky area eventually soaks into the soap and disappears, but sometimes it doesn't and I end up wiping it off. When I use it with restraint, the glycerin is absorbed completely by the soap leaving a nice fleck of mica behind. The mica layer is durable too -- it's hard to rub off with a dry finger or cloth.

So I enjoy using this technique but with some caution.
 
I poured glycerin on the top of my soap mixed with mica (please don't ask!), and it pooled terribly. I skimmed it off and drizzled the glycerin and then skewed. It left crevases with mica, similar to mica oil drizzle but deeper crevases. The tops were quite sticky for months where the glycerin I didn't manage to scoop off sunk in. After months (this soap is now well past the 6 month mark, yet after I'd guess 3-4 months) the stickinesss subsided. I'll post my blog on it. It's called Stonehenge. Scroll down for the effect of mica in glycerin drizzled on top of cp soap.
 
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