I made a dispersion of FD&C Red #40 aluminum lake pigment in castor oil, with a 33% strength, on a three roll mill. Dye load for this pigment is 21-24%. The resulting dye is very transparent and I'm having a very hard time making an opaque red lipstick with it, always getting a sheer red tint. I'm using the dispersion at 20% of my formula.
My question is, is FD&C Red #40 just really transparent or did I make the dispersion too weak? I'm using it at a rate consistent with what I've seen in formulas from ingredient manufacturers.
Since I want a strong red, I'm avoiding the use of titanium dioxide because it'll wash the color out to pink. Does anyone have any ideas on how to get strong color performance out of lake pigments?
My current lipstick formulation is a fairly standard blend of plant waxes and oils, with no particularly advanced ingredients. The most interesting things in there are Olivem 900 and high viscosity hydrogenated polyisobutene.