Drug – bio-affecting and body treating compositions – Topical sun or radiation screening – or tanning preparations
Reexamination Certificate
2000-03-10
2002-06-04
Dees, Jose G. (Department: 1616)
Drug, bio-affecting and body treating compositions
Topical sun or radiation screening, or tanning preparations
C424S070100, C424S070900, C424S070110, C424S070190, C424S070220, C424S401000, C424S060000, C510S130000, C510S135000, C510S136000, C510S137000, C510S138000, C510S158000, C510S159000, C514S846000, C514S944000, C514S945000
Reexamination Certificate
active
06399045
ABSTRACT:
FIELD OF THE INVENTION
The invention relates to liquid personal wash compositions comprising a sunscreen component and minimal required levels of cationic polymer. The compositions provide high deposition of sunscreen component; good SPF (“sun protection factor”) values as defined in applicants' SPF tests; and good consumer acceptable levels of lather.
BACKGROUND OF THE INVENTION
It is extremely difficult to provide liquid personal wash compositions with sunscreen components or agents which sunscreen components may be readily deposited on the skin or other surface. One significant problem is that the sunscreen agents will generally be solubilized by the surfactant and, while they may be deposited during lathering, they will be removed by rinsing.
The art does teach use of certain cationic polymers to enhance deposition of sunscreen materials onto the hair and protect from harmful effects of sunlight. U.S. Pat. No. 5,186,928 to Birtwistle, for example, teaches use of a cationic derivative of polygalactomannan gum for such purpose. The level of sunscreen is never at such a high level, however, that the sunscreen will not solubilize in surfactant solution (column 2, lines 54-57). By contrast, sunscreens of the invention are used in concentrations above their solubility limit in the surfactant system in which they are used at least in part to ensure minimum levels of deposition.
EP Publication 552024 to Unilever is also concerned with enhancing deposition of cosmetic agents, including sunscreens. Here, an additional oil phase is added in order to reduce solubilization of the oil/sunscreen into the surfactant phase thereby allowing more sunscreen to be available for deposition upon rinsing. The subject invention, by contrast, does not rely on an oil carrier to enhance deposition (the oil is said to reduce solubility of component in surfactant phase and thus enhance deposition). Further the subject invention requires use of relatively high levels of cationic polymer to both enhance deposition of sunscreen (sunscreens being used at much higher levels than those used in U.S. Pat. No. 5,186,928 noted above) and increase SPF (“sun protection factor”).
EP 313,303 (assigned to Procter & Gamble) discloses compositions comprising tocopherol sorbate (antioxidant) which may be used in combination with sunscreen agents. The compositions must also comprise anti-inflammatory agent and topical carrier. There is no recognition from this reference of using cationic polymer to enhance sunscreen deposition, particularly in formulations containing high amounts of sunscreen.
U.S. Pat. Nos. 4,701,321 and 4,933,174 to Bernstein teach method of using liquid detergent with sunscreen agent. The compositions contain only nonionic and amphoteric surfactants, unlike the cleansing compositions of the invention which must contain at least 5% anionic.
WO 99/13854 (assigned to Colgate) discloses a skin cleansing, sun protecting composition comprising (a) a sun protection hydrophobic agent; (b) a polar organic solvent less polar than water; (c) oil; and (d) cleansing effective amount of surfactant or mixture thereof wherein oil/polar solvent ratio is 1:4 to 1:0.8. In contrast to the aqueous systems of the subject invention, this is a non-aqueous system (see bottom of page 11).
Other references teach compositions which may contain surfactant, N-polymer and benefit agent (e.g., U.S. Pat. No. 4,948,576 to Verdiccio et al.; EP 117,135). These references fail to focus on sunscreens and/or to teach or suggest that sunscreens must be used in amounts beyond their solubility limit in the surfactant systems in which they are used; and that, when sunscreen is used in such large amounts, cationic polymer (at relatively large levels) both enhances deposition and SPF values.
BRIEF DESCRIPTION OF THE INVENTION
Unexpectedly, applicants have now discovered that minimum required levels of cationic polymer can be used to deposit sunscreen even in compositions comprising sunscreen at levels beyond their solubility limit in the surfactant system in which the sunscreen is found. This combination of high levels of sunscreen and cationic (as noted it was never previously recognized cationics could be used to provide enhanced effect even when such large amounts of sunscreen are used) leads not only to deposition of much greater amounts of sunscreen (at least 10 &mgr;g/cm
2
), but to enhanced SPF (at least 2). Further, compositions have lather of greater than 70 ml (using funnel test) and are good cleansing compositions. In some embodiments, crystallization control agents suppress crystallization of sunscreen component(s) and may help enhance deposition even further.
More specifically, compositions of the invention are opaque (less than 50% transmittance at a visible wavelength) personal wash cleansing compositions comprising:
(a) 5% to 70% by wt. of a surfactant or surfactants selected from the group consisting of anionic, nonionic, amphoteric or zwitterionic and cationic surfactants wherein at least one surfactant is an anionic surfactant comprising at least 3% by wt., preferably at least 5%, more preferably at least 7% by wt. of total composition;
(b) 0.5 to 5% by wt. of a cationic polymer;
(c) 1% to 35% by wt. of a sunscreen or mixture of sunscreens;
wherein concentration of sunscreen component (c) is above the solubility limit of the sunscreen component in the surfactant system in which said sunscreen component is used;
wherein the composition has SPF factor of at least 2, preferably 2.5, more preferably 3.0;
wherein the sunscreen has deposition of at least 10 &mgr;g/cm
2
preferably at least 15 &mgr;g/cm
2
, more preferably at least 20 &mgr;g/cm
2
; and
wherein composition has lather volume of greater than 70 ml using funnel test.
DETAILED DESCRIPTION OF THE INVENTION
The present invention relates to opaque (less than 50% transmittance at visible wavelength) personal wash cleansing composition comprising (percent by weight).
(a) 5% to 70%, preferably 7% to 60% of a surfactant or surfactant selected from the group consisting of anionic, nonionic, amphoteric, zwitterionic and cationic surfactants wherein at least one surfactant is an anionic surfactant comprising at least 3% weight by weight, preferably at least 5%, more preferably at least 7% of total composition;
(b) 0.5, more preferably at least 1.0% by wt. to 5% cationic polymer. Preferably the polymer is a cationically modifier guar (e.g. cationic derivative of guar);
(c) 1% to 35% preferably 3% to 30%, more preferably
5
% to 30% sunscreen or mixture of sunscreens;
wherein concentration of sunscreen component (c) is above the solubility limit of the sunscreen component in the surfactant system in which said sunscreen component is used;
wherein the composition has SPF factor of at least 2;
wherein the sunscreen has deposition of at least 10 &mgr;g/cm
2
; and
wherein composition has lather volume of greater than 70 ml using funnel test.
Surfactants
The surfactants of the invention may be chosen from the group consisting of anionic, nonionic, amphoteric/zwitterionic, cationic surfactants and mixtures thereof.
Examples of anionic surfactants are soap and anionic non-soap surfactants that can be exemplified by the alkali metal salts of organic sulfate having in their molecular structure an alkyl radical containing from about 8 to about 22 carbon atoms and a sulfonic acid or sulfuric acid ester radical (included in the term alkyl is the alkyl portion of higher acyl radicals). Preferred are the sodium, ammonium, potassium or triethanolamine alkyl sulfates, especially those obtained by sulfating the higher alcohols (C
8
-C
18
carbon atoms), sodium coconut oil fatty acid monoglyceride sulfates and sulfonates; sodium or potassium salts of sulfuric acid esters of the reaction product of 1 mole of a higher fatty alcohol (e.g., tallow or coconut oil alcohols) and 1 to 12 moles of ethylene oxide; sodium or potassium salts of alkyl phenol ethylene oxide ether sulfate with 1 to 10 units of ethylene oxide per molecule and in which the alkyl radicals contain from 8 to 12 carbon atoms, sodium
Aronson Michael Paul
Lam Andrew
Macaulay Ernest Weatherley
Morgan Leslie Jo
Puvvada Sudhakar
Dees Jos,e G.
Koatz Ronald A.
Lamm Marina
Unilever Home & Personal Care USA a division of Conopco, Inc.
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