Formulating with Surface Treatments

By: Shree Weaver

May 13, 2020

Miyoshi America is one of the leading companies worldwide that provides surface treated materials to the cosmetic industry.  A question that many new Cosmetics Chemists have is how do you formulate with surface treatments?  A very good question and the answer is….it depends! Let’s start with the basics. 

Hydrophobic Vs. Hydrophilic

We have hydrophobic and hydrophilic surface treatments. Hydrophobic surface treatments, to put it simply, love to be dispersed in oil.  Hydrophilic surface treatments love water.  So, how would you incorporate these two surface treatments into your formula? Let’s start with a hydrophobic surface treatment in a liquid foundation. Would you add the hydrophobic pigment/powder to your water phase? The answer is no. Could you add our hydrophobic pigment/powder to your water phase? The answer is YES!  In this instance, there needs to be some type of emulsifier/surfactant within the water phase to help to “wet” the hydrophobic pigment/powder (otherwise the hydrophobic powder will float on the surface of the water). 

It takes a bit more time and energy to disperse hydrophobic pigments into a water phase but in some instances, this has to be the case. For example, if the oil phase is very small, it’s just easier to add the pigments to the water phase. Now, for hydrophilic pigments, let’s ask ourselves the same questions.  Would you add the hydrophilic pigment/powder to your water phase? The answer is yes.  Could you add your hydrophilic pigment/powder to your oil phase?  The answer is IN SOME CASES.  Preferably, if a surface treatment is purposely hydrophilic, that means is works well in the water phase but sometimes it works just as well in an oil phase as is the case for Miyoshi’s PRIMROSE Pigments, which have a silica coating.  PRIMROSE pigments are excellent in water systems as well as anhydrous systems or oil phases.

Miyoshi’s Surface Treatments

Okay, does Miyoshi have a hydrophilic surface treatment that only prefers water and definitely should not be added to the oil phase? Yes, and that would be Miyoshi’s MiyoAQUA Pigments! MiyoAQUA pigments are surface treated with Algin and provide some thickening properties just as natural Algin does, providing excellent suspension in water. These pigments will agglomerate if added to the oil phase of a formula and could cause instability.  Click on the links below to learn more about Miyoshi’s PRIMROSE and MiyoAQUA surface treatments.

Until our next installment, from our Miyoshi family, please stay safe! 


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