United States Patent:   6,017,546

Assignee:  Dow Corning Corporation (Midland, MI)

Filed:  July 6, 1993

A water-in-volatile silicone emulsion gel having skin moisturizing qualities. The gel is formed by mixing an oil phase with a water phase. The oil phase contains a volatile silicone, a siloxane polyether, and an oil. The water phase contains water, a humectant, and an oxyethylene functional organosilane. Matching of the refractive index of the oil phase and the water phase results in the formation of a crystal clear gel having a viscosity in the range of 5,000 to 150,000 centistokes.

SUMMARY OF THE INVENTION

The invention relates to a water-in-volatile silicone emulsion gel having skin moisturizing qualities which is formed by mixing together an oil phase and a water phase. The oil phase contains a volatile silicone, a siloxane polyether, and an oil. The water phase contains water, a humectant, and an oxyethylene functional organosilane. The humectant should be a water soluble material having a refractive index above 1.35. Matching of the refractive index of the oil phase and the water phase results in the formation of a crystal clear gel having a viscosity in the range of 5,000 to 150,000 centistokes.

If the refractive index of the water phase is lower than the refractive index of the oil phase, the indices can be matched by the addition of more of the humectant. If the refractive index of the water phase is higher than the refractive index of the oil phase, the indices can be matched by the addition of more water.

In an alternate embodiment of the invention, the humectant is omitted from the water phase and the amount of the oxyethylene functional organosilane is increased. Crystal clear gels have been obtained with this technique in which the oxyethylene functional organosilane functions as the humectant.

Claim 1 of 16 Claims

1. A method of making a gel comprising (i) forming an oil phase having a volatile silicone, a siloxane polyether, and an emollient; (ii) forming a water phase having water, a water soluble humectant with a refractive index above 1.35, and an oxyethylene functional organosilane; (iii) measuring the refractive index of the oil phase and the water phase; (iv) matching the refractive indices of the oil phase and the water phase; (v) adding the water phase to the oil phase: and (vi) subjecting the phases to shear mixing; the volatile silicone being selected from the group consisting of cyclopolysiloxanes of the formula {(CH₃)₂ SiO}_x and linear siloxanes of the formula (CH₃)₃ SiO{(CH₃)₂ SiO}_y Si(CH₃)₃ in which x is three to ten and y is zero to four; and the oxyethylene functional organosilane has the formula RSiR'₃ in which R is the radical --O(CH₂ CH₂ O)_x R"; R' is R or an alkyl radical having one to six carbon atoms; and R" is selected from the group consisting of hydrogen, an alkyl group of one to six carbon atoms, and an aryl group; and x is six to thirty.

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