]. Soc. Cosmet. Chem., 22, 599-614 (September 17, 1971) Trends in Pressed Powder Technology MITCHELL I, SCHLOSSMAN, B.S., and ADRIAN J. FELDMAN, B.S.* Presented Decetnber 1-2, 1970, New York City Synopsis--A PRESSED POWDER is essentially a dry powder compressed in cake form to be applied to the body, face, or eyes with a puff, brush, or foam applicator. The parameters of RAW MATERIAL SELECTION and their uses in pressed powders are studied, and prop- erties imparted to the face and eyes are briefly indicated. Representative FORMULATIONS, and MANUFACTURING and PRESSING TECHNIQUES encompassing modern compact face powder, blusher. eyeliner, eyebrow, eyeshadow, and rouge are detailed. This paper briefly covers quality control, equipment requirements, manufacturing problems, fashions, and trends in pressed powder developments. INTROI)UCTION It was not until after World War I that the first pressed powder appeared on the market. The compact was a sixnple face powder molded into a pressed form by the addition of about 20% of plaster of Paris. The resultant product was very rough in texture and difficult to use. It required a lot of rubbing in order to remove sufficient powder for application (1, 2). Later improvements included the use of various gum binding agents. Most compacts, however, turned out either too hard or too soft. The next major advance in pressed powder technology occurred in the early 1930's when a facsimile of modern compact powder was prepared using petrolatum, ammonia, starch, and stearic acid as the binding agents (3). The first patents for cake make-up (4-6) were * Prince Industries Ltd., 2195 Elizal)etb Ave., Rahway, N.J. 07065. 599

600 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS prepared by adding the fillers and pigments to the oils and waxes dis- persed in water, drying the formed mixture, pulverizing the product, and compressing it into a cake form. Therefore, it appears that pressed cakes can be prepared from almost any good face powder provided a suitable binding agent is employed and a suitable compact press is utilized. CONSTITUENTS In general terms, a pressed powder may be considered simply as a face powder in a different physical form and, therefore, it is not sur- prising to find that the constituents found in both are similar. Some raw materials have good compression qualities, while others do not and cause swelling or crumbling after being pressed. Therefore, a proper balance of hard-to-compress and easy-to-compress raw materials and bind- ing agents must be utilized in preparing a suitable formulation. In prac- tice, the following raw materials should be considered: Fillers Talc is the most important single component found in pressed powders. It gives some coverage and exhibits slip, spreadability, and smoothness to the finished cake. Talcs vary in color, transparency, slip, shine, density, particle size, smoothness, and compressibility. Many pressed powder formulations contain more than one kind of talc in order to achieve the most desirable effects needed for the intended product use. Other ingredients used as fillers are kaolin, stearates, and carbonates. Kaolin imparts softness on application, has excellent adherent and ab- sorbent properties, and assists in wetting and binding. Zinc and mag- nesium stearates are water repellent, they promote skin adherence and film formation, and they aid in producing a firm cake. Calcium and •nagnesium carbonates increase bulk, have good covering power and water absorbency, and aid in compressibility. Binding Agents These chemicals consist of different grades of mineral oils, fatty esters, lanolin and derivatives, cellulose gums, natural gums such as tragacanth or Karaya, emulsifying agents such as sodium and triethanol- amine stearate, nonionics, and emulsions containing any and all of the aforementioned ingredients. Water and ethyl alcohol have been found successful as binding agents for difficult-to-press materials. Again, the