210 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS said to reduce somewhat the sting of the spirit and to leave a smooth, slight film on the skin. In pre-shave lotions for use with electric razors the inclu- sion of polyvinylpyrrolidone should assist in conditioning the hair for shaving and again would leave a smooth film on the skin. 8 (d) General Make-up So far we have discussed applications of polyvinylpyrrolidone which result in the deposition of a transparent film. Apart from its excellent film-forming properties polyvinylpyrrolidone is also an excellent pigment binder and dispersing agent, and it is therefore not surprising that it has found application in the formulation of liquid make-up, pancake, compressed powder make-up and mascara. Such applications so far appear to have particularly aroused interest in Germany, and it has been claimed that such make-up leaves the skin smooth to the touch. In mascara I understand that the use of polyvinylpyrrolidone can result in a non-eye irritant prepara- tion, but I believe that this can now be achieved by other means as well. It has been mentioned earlier, when discussing hair creams, that polyvinyl- pyrrolidone is an excellent emulsion stabiliser, and can therefore be used in the formulation of toilet emulsions, including pigmented emulsions such as tinted foundation creams. The use of polyvinylpyrrolidone in hormone cosmetic creams has been patented •9 and the polymer may also find possible applications in the formulation of special purpose barrier creams. TM In America they appear to be showing interest in the use of polyvinyl- pyrrolidone in lipsticks and in nail polish removers. The former application is possibly associated with polyvinylpyrrolidone's ability to form dyestuff complexes the latter use is not fully understood. (e) Shaving Creams The use of polyvinylpyrrolidone in shaving creams has also been sug- gested, •' particularly for use in aerosol packs. One would expect that such shaving creams would leave the skin feeling particularly smooth, and in addition, as mentioned earlier under shampoos, the polymer is' an excellent foam booster and stabiliser. (f) Tooth Pastes On the fringe of the toilet preparation class of product I would mention that the use of polyvinylpyrrolidone in tooth pastes has been patented. •8,•7,• It is claimed that the polymer's complexing ability assists in the removal of tartar and in removing tobacco stains. It has also been suggested that polyvinylpyrrolidone can be used with advantage in the formulation of chlorophyll-containing tooth-paste.

POLYVINYLPYRROLIDONE IN COSMETICS 2!1 (g) Per fuming , Perfume plays an important part in all cosmetic preparations, and atten- tion must be drawn to the fact that polyvinylpyrrolidone is a reactive polymer and can form complexes with appropriate substances. In certain cases this can result in the precipitation or gelling of polyvinylpyrrolidone and certainly will result in a change in its viscosity. It is, of course, also possible that the odour of the perfume might change through such com- plexing. It is therefore essential to ensure that perfumes used with polyvinylpyrrolidone are fully compatible. Very little has been published on this subject, but we are informed that most perfume and perfume raw material suppliers are now aware of this problem and can advise on the choice of suitable compounds. This property of forming complexes with perfumes has resulted in suggestions that the polymer may be of interest as a possible perfume fixative, and we have been advised that such properties and possible applications are being actively studied both in this country and overseas. Acknowledgement is made to the Directors of British Oxygen Research and Development Limited for permission to publish this paper, and to the various members of your industry for advice on the uses of polyvinyl- pyrrolidone in cosmetics. REFERENCES D.R.P. 737663, I.G. Farben. D.R.P. 738753, I.G. Farben. D.R.P. 744414, I.G. Farben. French P. 956,535, I.G. Farben. U.S.P. 2,658,045, General Aniline and Film Corp. Shelanski, Shelanski & Cantor, y. Soc. Cosmetic Chemists, 5, No. 2. 129-132. Drug. Trade News, July 6th, 1953. Chem. Eng. News, January 3&th, 1956, 500-503. B.P. 747806, General Aniline & Film Corp. Wilkinson, Stoner, Hay & Witwer, C.S.M..4. Proceedings, 40th mid-year meeting, Cincinnati, Ohio. Chern. Week, May 5th, 1956, 84. j. Pickthall, Soap, Perfumery • Cosmetics, May 1956, 553-557. Benk, Seifen-Ole-Fette-Wachse, 80, No. 10, 1954, 254-255. B.P. Appl. 28509/55, The British Oxygen Co., Ltd. Holmes & Witwer, American Dyestuft Reporter, September 26th, 1955, 702-704. B.P. 739936, Colgate-Palmolive Co. B.P. 741315, Colgate-Palmolive Peet Co. South African P. 14793, Colgate-Palmolive Peet Co. B.P. 701546, Te•mpia-Coliera & Hurlaux.