Lather -- really close up

[SiBurning]

A bit of bowl-lathered Czech & Speake Oxford & Cambridge. Looks like my technique could use some work. ;)
They're different colors because I don't have a full set of filters and had to use different colors to get the quantity of lighting right.

Fairly newly made


A bit later the bubbles start to collect into larger bubbles


scale 1mm divided into 100 divisions (Might be slightly off because it uses reflected lighting instead of transmitted lighting)


The difference in density between the two pictures is a lot more than it looks in a flat picture. Just think about how the difference also runs through the plane of the picture. You can see more stuff in the background in the first picture. The difference in the amount of light that came through those two was also drastically different--when I switched to the second picture, it was completely white because the light went through a whole lot fewer bubbles.

[Jethro1984]

Interesting...did you shave with it after the photos?

[SiBurning]

Interesting...did you shave with it after the photos?

No. Not only that, I only made a quick, small amount of lather. If there's any interest, I'll do some more--with more care, too--but I don't think it'll look much different.

[Drubbing]

I had wallpaper like that in the 70s.

[Walter Sobchak]

Very cool. Looks like trippy iguana skin.

[Jethro1984]

No. Not only that, I only made a quick, small amount of lather. If there's any interest, I'll do some more--with more care, too--but I don't think it'll look much different.

I'm curious about the scale. By my estimation with your scale, some of the bubbles are rather large. How on earth can they protect the face?

[justinp]

I'm curious about the scale. By my estimation with your scale, some of the bubbles are rather large. How on earth can they protect the face?

In fairness, it's not *all* that painful to drag a blade across the skin with only water to lubricate. I don't think you need huge amounts of buffer, only a little.

Raw speculation, obviously.

[Jethro1984]

In fairness, it's not *all* that painful to drag a blade across the skin with only water to lubricate. I don't think you need huge amounts of buffer, only a little.

Raw speculation, obviously.

Let's test that theory...Tomorrow you may use only water!

[BurkDarkpatches]

I think this is really interesting. Do you think the larger bubbles in the second photo are the result of the lather drying out? You may have found a way to objectively determine how well a soap lathers and how well it can maintain its moisture. There are other variables to control, but the thought is intriguing.

Some comparisons I'd be interested in: Tallow vs glycerin, Old Williams vs New Williams, best (general consensus) dirt cheap soap vs best (gen. con.) expensive soap, etc.

Thoughts?

Steve

[SiBurning]

I think this is really interesting. Do you think the larger bubbles in the second photo are the result of the lather drying out? You may have found a way to objectively determine how well a soap lathers and how well it can maintain its moisture. There are other variables to control, but the thought is intriguing.

Some comparisons I'd be interested in: Tallow vs glycerin, Old Williams vs New Williams, best (general consensus) dirt cheap soap vs best (gen. con.) expensive soap, etc.

Thoughts?

Steve

All foams collapse over time. Nothing to do with drying out. It's just the dynamics of any foam. There's some articles on foam linked in the wiki. If I remember correctly, the curve suggests that a more perfect foam would last longer--that once you have larger bubbles, it sort of accelerates the collapse, or put the other way, a perfect foam with all the same size (optimally small) bubbles has a lower energy and that slows down the drainage. Also, the rate of collapse has a lot to do with chemical and electrical-atomic energies, not just gravity/drainage, so different soaps or creams will collapse at different rates. All of this is true for fire fighting foams, and foaming (or anti-foaming) agents in gasoline.

[SiBurning]

I'm curious about the scale. By my estimation with your scale, some of the bubbles are rather large. How on earth can they protect the face?

Admittedly, it's not a great lather to begin with. Then again, sitting on your face, any lather's going to collapse, so you'll end up with larger bubbles no matter what. I have no answers or speculation here, except I've always thought bubbles were overrated for shaving.

[Jim]

Just to throw a log on the fire, I always considered the lather to be an emulsion of water and soap- a mixture without much air at all so no foam.

I would be very happy to see a lather that you consider excellent and one you found to be lacking.

You are really doing us all a great service with these fine posts Steve.

[SiBurning]

Just to throw a log on the fire, I always considered the lather to be an emulsion of water and soap- a mixture without much air at all so no foam.

I would be very happy to see a lather that you consider excellent and one you found to be lacking.

You are really doing us all a great service with these fine posts Steve.

I think a really good lather would be almost completely made of very small bubbles, with an average size of around 30 microns--3 of those small lines. From my reading, this would hold the maximum amount of water without running, and be most stable. With the naked eye, this would not look like a foam, but I think would act like one.

I agree with you about the I'd really love to try to shave with an emulsion, but I wonder if it would be very runny, nothing at all like egg whites, and would probably be hard to form peaks. I don't think I could make a non-foam emulsion with a brush. Maybe a spoon.

I actually have just such an emulsion on hand from months ago. I'll snap a picture immediately.

[nff]

verry cool now do some barborsoll.

[Jethro1984]

verry cool now do some barborsoll.

That's actually a great idea. Let's see what the junk foam goo looks like.

[SiBurning]

In December 2009, I prepared 5% solution of Tabac and Art of Shaving soaps in distilled water for the Anyone got a microscope? thread. In that thread, these solutions were used to treat hair. They were made by heating the water and stirring the contents until the soap was completely absorbed. I noted at that time that the AoS formed a slick, consistent gel, while the Tabac was slimy and stringy.

Here are those preparations under the microscope at the same magnification as the earlier pictures in this thread. You can see the relative consistency of the preparations.

Don't read too much into the differences between these two emulsions from the pictures. They were both heated to near boiling, so there may be something in the Tabac that reacts at that temperature that you'd never experience when shaving.

5% AoS


5% Tabac

[Jethro1984]

Seems the AoS is much more consistent. Or am I looking at those wrong?

[SiBurning]

I don't know how to interpret the pictures. There's some structure to both that bends the light.

To the naked eye, the AoS looks and feels like a smooth gel with a fine structure. There are a small number of bubbles contained within the gel, probably those that were trapped in the gel formed while mixing the still hot liquid. It tends to keep its shape and can be sliced cleanly with a knife. Under the microscope you can see how fine the structure is because there's little to see. Perhaps some kind of dye would help with that. You do see a couple of bubbles, though.

To the naked eye, the Tabac is slimy and stringy, and has some component that's partly separated that has a velvety look and texture. When I dip a glass rod into the bottle to get some out, it pulls and hangs like long strings. It is a thick liquid that leaves slimy, stringy trails when the bottle is turned. The trails are covered and saturated with a velvety substance that appears to stay with the thicker, slimy part, and also appears to be more liquid. Under the microscope, you can see something of the strings and structure, as well as a few bubbles, and some small clumps that pervades the liquid.

I can only guess at what we're seeing in the Tabac. There's one or more insoluble components, as well as long chains of probably fatty acids. Technically, both are mostly insoluble--they're not solutions, they're emulsions--but the AoS forms much smaller pieces.

[Jethro1984]

the AoS forms much smaller pieces.

That's exactly what I was seeing. It seems as though the AoS nearly completely mixed, while the Tabac did not. That would explain the smoothness vs. the stringy/stickness you observed with the Tabac.

[SiBurning]

Just to throw a log on the fire, I always considered the lather to be an emulsion of water and soap- a mixture without much air at all so no foam.

Everything I've read says that what we shave with is both a foam and an emulsion. The emulsion is just the liquid that makes the foam.

The one thing I can't find or figure out is why we shave with a foam. A foam certainly helps carry away particles, like hair and skin. That's why all soaps, detergents, and tooth paste has bubbles. There is something special about the lubricating properties of a foam, but maybe the physics is beyond me and I'm just missing what's being explained in some of those documents in the wiki.

Here's an experiment for you. Make some lather, let it sit, and monitor it while it collapses. I'm guessing you'll see bubbles form on the inside over time.