Q from RainbootedRobot: Almay makes a foundation called “SmartShade” that is supposed to magically change to match your skin tone. It comes out of the tube looking white with little black specks in it, but as you rub it into your skin, it turns to a fleshy colour. What kind of sorcery is this?

A: This is a very interesting question!  As a background for readers of the unfair gender, foundations are skin coloured cosmetic applied to the face to create an even, uniform colour to the complexion — usually to cover flaws.  That is…

What foundations do

What foundations do

The problem is, if the color of the foundation doesn’t match the skin, then you get the Miscolored Girl Syndrome.

Miscolored Girl Syndrome

What this “SmartShade” is supposed to do is to match any skin tone – like magic.  But how does this work?

What Consumers think it does

Since this is so wonderful, it must be patented, and your gentle friendly chemist went on a patent search.  In a patent called “Makeup compositions and Methods“, it was claimed that the new invention includes

Emulsion makeup compositions for keratinous surfaces which change color upon application, emulsion makeup compositions that match a variety of skin or hair shades in more than one skin tone category […]

This patent was filed by Revlon, the parent company of Almay, and the date and content are both consistent.  Ladies and gents, we’ve got a match, so let’s dig in and see how the magic works.

To understand the magic, it has to be compared with non-magic.  In normal foundations the pigment (which gives the color) is blended with the rest of the ingredients into a paste:

Normal foundations have pigments all blended in.

…but NOT in SmartShade.  Using pretty interesting chemistry, the hydrophilic pigments are blended into a hydrophobic carrier to give an emulsion – this is like making oil-droplets in water, but reverse (water droplets in oil).  The technological challenge was to keep them like this all the while it’s traveling from the factory to the shelf to the makeup bag.

Smart shade's "water in oil" formulation

When you put it on, the hydrophilic pigments goes, SWOOOSH, right to your skin and spreads out evenly.  It looks as if it’s switching colors to match the skin tone.

“But, but – ,” I hear you protest, “That’s smoke and mirrors!  It’s not what I thought it claims to do!”  Yes, and it really is only smoke and mirrors and the manufacturers know it.  Let me quote from the patent — straight from the horse’s mouth:

In the case of a composition applied to skin such as foundation makeup, the development of the color directly on the skin from a non-skin matching color to a skin matching color gives the consumer the impression that the composition is “smart” and capable of changing color to exactly match her skin tone.

It’s not doing any matching.  Which explains why these “smart” foundations comes in different colors, and reviews about its color-matching abilities are rather mixed.  Is Almay going to be the subject of a class action?  Probably not – their marketing materials are misleading, but very carefully so.  Phrases like

The lightweight formula starts out white and adjusts to right.

is indeed itself adjustable to right.

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