Pigment Suspension

Formulating

Pigment Suspension

Posted by hishine1 on November 13, 2014 at 7:57 pm

Hi

Can anyone give me a couple of ideas for pigment suspension in a volatile liquid? Ethyl Alcohol, Cyclopentasiloxane base. Currently using a predispersed pigment in Isododecane.

Thanks

RawMaterialGirl replied 9 years, 11 months ago 5 Members · 12 Replies
12 Replies

Bobzchemist

Member
November 14, 2014 at 10:33 am

http://www.gayson.com/en/

http://www.gayson.com/en/products/colors-for-cosmetics 
hishine1

Member
November 14, 2014 at 6:17 pm

Thanks for those links Bobzchemist

Would these colours still not precipitate to the bottom of my bottle? I need to keep the formula super simple for cost. Quick dry hence the Ethanol (50%), Cyclo with 3% Dimethiconol/Cyclo for a little gloss. Ideal would be to package into clear bottles. Any other additives I should be using?
belassi

Member
November 14, 2014 at 6:53 pm

I don’t see why a water-soluble pigment should settle? It doesn’t settle in shampoo, for instance!
hishine1

Member
November 14, 2014 at 8:01 pm

@ Belassi … I made the base mix as above, I used (Sensient) a pigment dispersion in Isododecane (Carbon Black/oxide) and it settles within 6 hrs.

no water here other than in the Ethanol (97.5%).

do you have any ideas?
belassi

Member
November 15, 2014 at 10:32 am

It’s not a water soluble pigment, is why.
Bobzchemist

Member
November 15, 2014 at 12:57 pm

There is no such thing as a water soluble pigment. By definition, any soluble colorant is called a dye. Pigments are always insoluble particles - without a suspending agent, the particles will settle out.
belassi

Member
November 15, 2014 at 7:57 pm

Then why, can I add some blue pigment to water, and it will never settle out? Such as fluorescein I should think…
Anonymous

Guest
November 18, 2014 at 5:47 am

yours is a difficult question to answer depending on the use of your formulation. If it’s a normal dye the pigment should readily dissolve in water, otherwise you need to check you need to check your HLB (hydrophili-lipophile balance) of the surfactant if it’s a suspension or emulsion. Depending on whether it’s a nonionic or ionic surfactant, you’ll be able to choose which to use for your formulation. Secondly the viscosity of your formulation will affect migration of your pigment (be it settling or creaming). In this case then your vehicle must be something viscous depending on the intention of your formulation.
Ruben

Member
November 18, 2014 at 4:41 pm

@ Belassi Probably because fluorecin has a small solubility in water
Anonymous

Guest
November 25, 2014 at 2:05 pm

I have successfully dispersed FDC colorants in Castor Oil. 1:1 ratio… my understanding is that the liquid can be viscous.enough to suspend the color. example you can use. iron oxide dispersed in castor etc. you can disperse in silicones. you can disperse in glycerin.

but remember that the amount of castor or item you disperse may change your formulas outcome.

I am a Nurse not a Chemist..
hishine1

Member
November 28, 2014 at 7:43 am

Thanks everyone Im not at all familiar with dyes etc, but obviously what I need is a dye instead of a pigment. I have since tried several direct dyes and they will suffice with some formula modification.
RawMaterialGirl

Member
November 29, 2014 at 1:49 am

Cali SCC just had David Steinberg do a presentation on colors - go to http://www.caliscc.org/education and look for the blog article about color. There is also a presentation to download. May give you a good insight into pigments, lakes, dyes, etc.

Anonymous

Anonymous