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Old 04-08-2008, 04:10 PM
Khadaji Khadaji is offline
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What is the difference between foaming hand soap and regular?

Or perhaps phrased another way: How do they make foaming hand soap foam? Is it just that it has more water in it?
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Old 04-08-2008, 04:20 PM
Lanzy Lanzy is offline
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My guess is more air. Bubbles.

o, that WAS a guess.
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Old 04-08-2008, 04:23 PM
thirdname thirdname is offline
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I've wondered about this. I like the foaming soaps they're using in public restrooms. I can wash quicker with them because they're already lathered up, as opposed to a thick liquid. I've wondered whether they have some sort of manual air pump, or a pressurized vessel, some chemical reaction or what. Maybe just a big bag of foam?
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Old 04-08-2008, 04:24 PM
gazpacho gazpacho is online now
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They have a pump that forces air into it to make the foam. I have a refillable one at home and the instructions that came with it say to put 1 part normal liquid soap to 4 parts water. So another difference is the foaming soaps contain a lot more water.
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Old 04-08-2008, 04:25 PM
Maastricht Maastricht is offline
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If you mean the kind of soap that comes out the nozzle as foam, I think that is because of the dispenser, which adds air to a mixture of diluted soap.

That said, some basic detergents foam more then others. The cheapest liquid detergent, which is a staple ingredient in shampoos, and other liquid soaps (and even in toothpaste) is Sodium laureth sulfate, or SLS. That one creates a lot of foam in watery solutions, so much so that when it is used in products where foam is a nuisance (like toothpaste or some types of dishwasher liquid, where foam clings to the clean glasses) it requires that an anti-foam substance is added.

ETA: a lot of the liquid soap that comes out of dispensers is also watered down, but thickened up with a thickening agent. That made me feel less bad about washing globs of it down the sink. But I agree that foamed up soap is more efficient to use.

Last edited by Maastricht; 04-08-2008 at 04:27 PM..
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Old 04-08-2008, 04:30 PM
NunOfTheAbove NunOfTheAbove is offline
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It the SDS, or Sodium dodecyl sulfate (sometimes called sodium lauryl sulfate). It's a pretty common detergent.

Here is a wiki -
http://en.wikipedia.org/wiki/Sodium_Dodecyl_Sulfate

You beat me to it...

Last edited by NunOfTheAbove; 04-08-2008 at 04:31 PM..
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Old 04-09-2008, 09:43 AM
Tastes of Chocolate Tastes of Chocolate is offline
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Quote:
Originally Posted by gazpacho
They have a pump that forces air into it to make the foam. I have a refillable one at home and the instructions that came with it say to put 1 part normal liquid soap to 4 parts water. So another difference is the foaming soaps contain a lot more water.
We just buy a disposable foaming soap dispenser at the store, and when it runs out, refill with liquid soap + water, rather then throw it away. In the bathrooms, it's shower gel, in the kitchen it's dish soap. The dish soap mix makes it really easy to clean just 1 dish or pan, without getting way to much soap.
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Old 04-09-2008, 09:54 AM
Khadaji Khadaji is offline
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Thanks guys. It seems that as usual I am guilty of phrasing my question poorly. Of course I get foam. I understand that air is injected.

What I was wondering is the difference between regular liquid soap and the kind in dispensers that inject air into it creating the foam.

gazpacho has confirmed my hunch that you don't just use regular liquid soap, but instead must water it down - and has provided the ratio.

My fault for phrasing it poorly.
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