Patent ID: 6180117
Filing Date: 2001-01-30
Classification: A61K,A61Q,C08J,C08L,Y10S

Abstract:
A process for preparing a transparent microemulsion comprising:(a) preparing a blend comprising a low amino content silicone and an MQ resin wherein said low amino content microemulsifiable silicone has the formula:M(R.sub.a Q.sub.b SiO.sub.(4-a-b)/2).sub.x (R.sub.c SiO.sub.(4-c)/2).sub.y Mwherein R is a hydrocarbon or hydrocarbon radical having from 1 to about 6 carbon atoms, Q is a polar radical having the general formula --R.sup.1 HZ, wherein R.sup.1 is a divalent linking group bound to hydrogen and a radical Z wherein R.sup.1 is comprised of carbon and hydrogen atoms; carbon, hydrogen and oxygen atoms, or carbon, hydrogen and nitrogen atoms; and Z is an amino containing radical having the formula:--N(CH.sub.2).sub.z (CH.sub.2).sub.zz NHwherein z is one or greater and zz is zero or greater subject to the limitation such that when zz is zero Z has the formula:--NH(CH.sub.2).sub.z NH.sub.2wherein z is one or greater; a ranges from about 0 to about 2, b ranges from about 1 to about 3 such that a+b is less than or equal to 3, and c is a number in the range of from about 1 to about 3; and x is a number in the range of from 5 to about 2,000, and y is a number in the range of from about 800 to about 10,000, and M is a silicone endstopping group; and wherein said MQ resin has the formula: ##STR2##where both R.sup.1 and R.sup.2 are independently selected from the group consisting of alkyl hydrocarbon radicals having from 1 to 12 carbon atoms, and both M.sup.1 and M.sup.2 are independently selected from the group consisting of phenyl, phenethyl, polyether, hydrogen, and alkyl hydrocarbon radicals having from 1 to 23 carbon atoms in any combination subject to the limitation that the ratio of the subscripts j, k, and l satisfies the following relationship:0.5.ltoreq.(j+k)/l.ltoreq.4.0.(b) adding a surfactant having a phase inversion temperature ranging from about 45 to 0.degree. C. about 95.degree. C. to said blend;(c) heating said blend and said surfactant to a temperature ranging from about 45.degree. C. to 95.degree. C. said temperature being below the phase inversion temperature of said surfactant;(d) adding part I water;(e) adding an acid; and(f) adding part II water said microemulsion being cooled whereby said microemulsion has an ASTM D871 haze below about 150 and a mean particle size ranging from about 0.005 microns to about 0.050 microns.