Soaps

[Specialist]

Hi everyone I've a question for u...

We use lots of clolored soaps in our daily life. Yellow, Green or Red ect. I've just want to know how these colored soaps dont give color to our hand while we re washing our hands? All the soap foams seem colorless. So how Chemists provide color to the soap which can not be observed while they re been used.

Thanks

Specialist

[RyanJ]

Hi everyone I've a question for u...

We use lots of clolored soaps in our daily life. Yellow' date=' Green or Red ect. I've just want to know how these colored soaps dont give color to our hand while we re washing our hands? All the soap foams seem colorless. So how Chemists provide color to the soap which can not be observed while they re been used.

Thanks

Specialist[/quote']

 

Welcome to SFN!

 

Here is a guess, they react with the water rendering them colourless but I am not shure.

 

Maybe an expert can provide more information

 

Cheers,

 

Ryan Jones

[akcapr]

The reason the foam isnt colored is because there is only a little bit of dye in the actual product, but, this is kindof hard to explain, but because the soap foams and you get alot of bubbles that are really thin you cant really observe the color in the foam even though the color is still there.

[woelen]

The answer of akcapr is correct. There only is very little color in the solid soap.

 

Due to scattering of light in the foam, the color becomes less visible. The finer the foam, the less of the color can be observed.

 

A nice experiment which demonstrates this scattering effect is to take a small piece of colored soap (or even better, take a small piece of a strongly colored hard and brittle sweet). Crunch the piece into a fine powder. The finer the powder, the lighter the color. This effect is the same as with the foam.

 

Because there only is such a small amount of dye in the soap, any coloration of your skin will be unnoticed.

[Specialist]

thank u all...

[Hephaestus]

I've notice recently that orange coloured liquid soaps, when acted on by hypochlorite, produce bright orange azo- oxidation products. Amine based dyes are hence commonly used.