Aqueous silicone polyether microemulsions
Silicone polyether microemulsions are disclosed containing i) at least 20% by weight of a water immiscible dispersed phase comprising certain polydialkylsiloxane-polyoxyalkylene copolymers having 0.1 to 10 wt % ethylene oxide (C 2 H 4 O) groups, optionally a water immiscible silicone or hydrocarbon fluid, and ii) at least 5% by weight of an emulsifier. The silicone polyether microemulsions are optically transparent and have an average particle size of less than 100 nanometers. They may be used in a variety of personal care product formulations. In particular, the silicone polyether microemulsions may be used to prepare “clear” personal care products.
1. An aqueous silicone polyether microemulsion consisting of:
i) at least 20% by weight of a water immiscible dispersed phase comprising:
A) a polydialkylsiloxane-polyoxyalkylene copolymer having the average formula
R 1 3 SiO[R 1 2 SiO] x [R 1 R 2 siO] y SiR 1 3 or R 1 2 R 2 SiO[R 1 2 SiO] x SiR 1 2 R 2
wherein x ranges from 50 to 1000, y ranges from 1 to 50,
R 1 is an alkyl group containing 1 to 6 carbon atoms,
R 2 is a polyoxyalkylene group having the average formula
—R 3 O(C 2 H 4 O) a (C 3 H 6 O) b R 4 wherein
a is greater than 4, b ranges from 0 to 10,
R 3 is a divalent hydrocarbon group containing 2 to 12 carbon atoms,
R 4 is hydrogen, R 1 , or an acetyl group,
with the proviso that the polydialkylsiloxane-polyoxyalkylene copolymer
contains 0.1 to 10 wt % ethylene oxide (C 2 H 4 O) groups,
B) optionally, a water immiscible silicone or hydrocarbon fluid, and
ii) at least 5% by weight of
C) an emulsifier selected from an anionic surfactant, a cationic surfactant, a nonionic surfactant, or a combination thereof,
wherein the silicone polyether microemulsion is optically transparent and has an average particle size of less than 100 nanometers.
2. The microemulsion of claim 1 wherein the emulsifier is a surfactant or combination of surfactants capable of forming bi-layer structures when 20-80 wt % of the surfactant is dispersed in water.
3. The microemulsion of claim 2 wherein the formed bi-layer structures are lamellar phase structures.
4. The microemulsion of claim 1 wherein the polydialkylsiloxane-polyoxyalkylene copolymer has the average formula R 1 3 SiO[R 1 2 SiO] x [R 1 R 2 SiO] y SiR 1 3 .
5. The microemulsion of claim 4 wherein x is 205 to 500, y is 1 to 20, R 1 is methyl, and R 2 is —CH 2 CH 2 CH 2 O[C 2 H 4 O] a H where a is greater than 4.
6. The microemulsion of claim 1 comprising 40-60 wt % of the water immiscible dispersed phase and 10-40 wt % of C) the emulsifier.
7. A method of making the silicone polyether microemulsion of claim 1 consisting of mixing:
at least 20% by weight of:
A) a polydialkylsiloxane-polyoxyalkylene copolymer having the average formula
R 1 3 SiO[R 1 2 SiO] x [R 1 R 2 SiO] y SiR 1 3 or R 1 2 R 2 SiO[R 1 2 SiO] x SiR 1 2 R 2
wherein x ranges from 50 to 1000, y ranges from 1 to 50,
R 1 is an alkyl group containing 1 to 6 carbon atoms,
R 2 is a polyoxyalkylene group having the average formula
—R 3 O(C 2 H 4 O) a (C 3 H 6 O) b R 4 wherein
a is greater than 4, b ranges from 0 to 10,
R 3 is a divalent hydrocarbon group containing 2 to 12 carbon atoms,
R 4 is hydrogen, R 1 , or an acetyl group,
with the proviso that the polydialkylsiloxane-polyoxyalkylene copolymer
contains 0.1 to 10 wt % ethylene oxide (C 2 H 4 O) groups,
B) optionally, a water immiscible silicone or hydrocarbon fluid, and at least 5% by weight of
C) an emulsifier selected from an anionic surfactant, a cationic surfactant, a nonionic surfactant, or a combination thereof,
and sufficient water or an aqueous phase to sum to 100% by weight.
8. A method for treating fibers comprising applying to a fiber the microemulsion according to claim 1 .
9. The method of claim 8 where the fiber is a hair fiber.
10. The method of claim 9 where the microemulsion is applied to the hair fiber from a personal care product composition.
11. The method of claim 10 where the personal care product composition is a shampoo, leave-on conditioner, rinse-off conditioner, conditioning spray, hair styling spray, hair styling gel, shower gel, or styling composition.
12. A personal care product composition comprising the microemulsion according to claim 1 .
13. The personal care product composition of claim 12 where the personal care product is a shampoo, leave-on conditioner, rinse-off conditioner, conditioning spray, hair styling spray, hair styling gel, shower gel, or styling composition.
14. The personal care product composition of claim 13 where the personal care product is a shampoo.