It occurs to me that it might be useful to post what I know about this topic relating to creams. My own formulations do not use any form of emulsifying wax. Instead I use carbomer (current best of these is Ultrez-20) Why? It's because I want a cream that absorbs quickly. Our active ingredients are IN the cream - they're no use sitting on top of the skin. Secondly, it can be a damn nuisance having to sit around with greasy hands unable to touch anything waiting for the cream to absorb. Cross-polymers can give any consistency you like. They also create a medium which won't separate even if you're 'light' on emulsifiers.
Creams can be described by a two-word combination of light to heavy. EG: light-light = a cream that goes on with a light touch and absorbs quickly. heavy-light = a cream that is substantial, getting towards a butter in consistency, but still absorbs rapidly. All my own formulations are of the type ?->light. The hand cream for instance is a heavy-light, the face cream is a medium-light, and the burns treatment cream is a light-light. If I wanted to make a ?->heavy cream I would use an emulsifying wax instead of or in addition to the carbomer.
So, when you want to design a cream, first find out what your intended customer base prefers. Then formulate accordingly.
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