formulation with aluminium coated nano Titanium dioxide

Formulating

formulation with aluminium coated nano Titanium dioxide

Posted by rosa on June 10, 2014 at 11:46 am

Hi, I have made a couple of trials with the aluminium coated nano Titanium dioxide as I like the effect it has on the skin. When I do a very basic formulation there is no problem. But when I add all ingredients it separates - immediately at first, then it emulsifies but eventually the emulsion leaks..

Does anyone have any idea what ingredient that could be the problem? I am using; green tea extract, aloe vera, glycerine, GABA, Niacinamide, pro vit B5, hyaluronic acid in water phase.

Since the immediate separation occurs before additives go in, I assume it is a problem with either of these as most oils+butters are not very problem causing? I also use vitamin C ester…

Very grateful if I can get help! Rosa

Bill_Toge replied 10 years, 4 months ago 5 Members · 12 Replies
12 Replies

rosa

Member
June 10, 2014 at 11:48 am

Also, is there any kind of database for ingredients compatibility?
chemicalmatt

Member
June 10, 2014 at 12:23 pm

Rosa, there is not enough information to make a judgement here. You did not mention the surfactant system, nor any colloid or gum you may be using to emulsify and stabilize this product, which I assume is an o/w emulsion. Also, is the Al-coated TiO2 among the “additives” you mention? If the ingredients listed above are the additives, added last, and the separation occurs before these are added, then it lends evidence of a sytemic problem, not necessarily a compatibility issue.
Chemist77

Member
June 10, 2014 at 12:23 pm

Rosa analytical approach would be to make a lab bulk without the additives and distribute in equal parts. Add one additive to each part and check which one is making the emulsion unstable. Hope you can have a better approach from more learned members who can point out the exact culprit.
Bobzchemist

Member
June 10, 2014 at 12:49 pm

1) Run a series of knock-out experiments, that way you’ll know for sure.

2) Are you sure that you’re putting enough energy into your emulsification process?

3) No, there is not a single database for compatibility. Some suppliers may call out particularly incompatible ingredients on occasion. Look on the bright side - if it was easy to figure out which ingredients are compatible/incompatible, they wouldn’t have to pay us.
rosa

Member
June 10, 2014 at 1:46 pm

Hi, and thanks a lot for the input! The ingredients I listed are the base ingredients (before adding the additives) as separation occurs when I pour my oils in the water..

The Al-coated TiO2 is in the water phase, not as additive. O/W emulsion with ~80% water

I have been doing trials now for hours! It appears to be either GABA or the green tea extract, I believe that causes the instability, together with the TiO2.

I have no gum in the formulation, just Olivemulse (olivem1000) and no co-stabilizer..

Will tell when I know..thanks again/Rosa
rosa

Member
June 10, 2014 at 5:11 pm

Hi, it really appear to be the green tea extract that is the culprit - the least one I expected! I also did another experiment with red wine polyphenols - same thing. Is this common that polyphenols are destabilizing? I suppose green tea extract contains polyphenols as well? And why would it react with the Al-coated TiO2?

Thanks again!
Bill_Toge

Member
June 10, 2014 at 6:27 pm

if the emulsion is bleeding rather than creaming, that suggests it’s being destabilised by an interaction at or near the interface of the emulsion, involving the emulsified droplets, the TiO2 and the polyphenols

as polyphenols usually have several fused aromatic rings (comprising a big flat section), they have a lot of surface area available for adsorbtion onto compatible surfaces

have you tried it with the green tea/red wine polyphenols and no TiO2?

(also, is your TiO2 coated with aluminium or alumina?)
Chemist77

Member
June 10, 2014 at 9:40 pm

@Bill_Toge Simply great, and yeah I suppose the TiO2 is the one with alumina and silica.
Bobzchemist

Member
June 10, 2014 at 10:10 pm

@Rosa,

Almost all powder particles, nano-sized or not, will need a suspending agent to keep them from settling out of your
Bobzchemist

Member
June 10, 2014 at 10:10 pm

@Rosa,

Almost all powder particles, nano-sized or not, will need a suspending agent to keep them from settling out of your emulsion. Also, your emulsion will need more robust emulsifiers than a non-pigmented one would.
rosa

Member
June 11, 2014 at 9:19 am

Hi and thanks a lot for your help!

I made a cream batch yesterday without the green Tea extract. It actually turned out very different from what it used to turn out like. Seems very stable and a lot stiffer.

Yes, the TiO2 I am using is coated with aluminium alone and is water based..

I only tried yesterday with the red wine polyphenols, and it behaved exactly like the green Tea extract. I should have made a test batch with the green tea extract alone, that’s true. However, I am using it a lot in most of my other creams, sometimes combined with nano SiO2 and I think it has been fine.

I did question in another thread about the browning and I now think it could also be caused by the green Tea extract as was mentioned here (thanks!). Waiting for supplies and will make cream asap to find out, although it might take a while until it goes a bit brown usually. Will post as soon as I know and thanks again for all the help! Rosa
Bill_Toge

Member
June 22, 2014 at 6:34 pm

if it really is coated with aluminium you’ll want to issue your manufacturers with heavy duty dust masks when it goes to production; you don’t want them coming down with metal fume fever