Apparently there is considerable uncertainty on the part of the druggist as to the composition and properties of the several types of toilet creams now in popular demand. As these are usually most in demand during the summer months this class of toilet preparations will be considered first, later articles treating in due turn of others in constant demand. At the beginning the writer wishes it distinctly understood that he is making no attempt to write a treatise on toilet preparations as a master of that art; the articles are inspired by the desire to put in compact form as many reliable formulas and working methods for the manufacture of toilet preparations by the druggist as have proved practical in his experience. Few of the formulas are original, most of them are selected from contributions to the American Pharmaceutical Association and local and state associations, but all can be said to be good and workable. Foreign periodicals and books have also been freely drawn upon. Our American pharmaceutical journals and their contributors have given invaluable aid in this work, and so far as possible credit will be given where due. Preference has been given to formulas contributed by members of pharmaceutical associations and from pharmaceutical journals as being those best adapted to the facilities and apparatus of the average drug store, as these can easily be modified by practical experience to working on a larger scale.
Toilet creams may be roughly divided into four classes: (1) Cold creams of the U. S. P. type; (2) Cold creams containing mineral fats and oils; (3) Massage creams, with casein as a basis; (4) Vanishing creams, so called, with sodium stearate or other soaps as a basis. A fifth variety might be added, Liquid creams, containing oils or fats emulsified with tragacanth, agar agar, honey or other agents. There is a much advertised type of toilet cream which is nothing else than a mucilaginous mixture containing solids and fats in suspension, but these are hardly worthy of attention. Another type, widely advertised, is merely our friend Epsom salts in solution with a little glycerin and gum.
Before quoting formulas and working directions for the different types of toilet creams, a few comments may be advisable. First and foremost, to be successful a toilet cream must be adapted to its environment. Neglect of this essential point has cost many dollars to enthusiastic manufacturers who failed to adapt their formulas to meet the varying climatic conditions of the various sections in which their goods were advertised and sold. Certain manufacturers of toilet goods having a world-wide sale ship new products to their agents for tests of their keeping qualities under trade and climatic conditions in every quarter of the globe, and find that it pays them. Of course the druggist cannot do this, but he can test the keeping qualities of his toilet creams easily by utilizing his refrigerator and his heating system. Faults and defects can thus easily be detected at little expense and costly mistakes be prevented, and the necessary variations in formula for summer and winter manufacture quickly determined. Another important point is selection of the most economical and suitable container, which can also be determined by tests under conditions simulating local climatic changes. Labeling, dressing, etc., are too important to be treated as an incidental, so these will be given appropriate space later.
Adaptation of a toilet cream to average conditions depends largely upon the nature of its ingredients as well as their proportion. A very common mistake is the use of an easily oxidized months. Spermaceti is an example of this fault. While an excellent ingredient for a cold cream to be used medicinally and made freshly at short intervals, it is quite unsuitable for a cold cream for the general trade, as it gets rancid and imparts a disagreeable odor to the preparation. Paraffin wax is the best substitute for spermaceti, being obtainable in a wide range of melting points. The liquid white paraffin oils are also most suitable for creams for general sale, as they do not oxidize as do animal and vegetable fats and oils.
There are so many details of manipulation in the manufacture of a smooth, permanent toilet cream that it is hard to decide where to begin. Perhaps temperature is the most important, that is, adhering rigidly to temperatures during manufacture that are best adapted to the peculiar nature of the ingredients used. Heating a mixture of oils and waxes too highly will seriously affect the properties of these materials, while insufficient heat will prevent thorough emulsification and cause a lumpy, greasy appearing cream. One detail is essential, aqueous ingredients and oily ingredients must always be at, or near, the same temperature when mixed. For instance, if a cool solution of sodium carbonate be added to the melted mixture of stearic acid and oil to make a vanishing cream, there will be instant solidification of some of the stearic acid and hence its incomplete saponification unless the mixture be heated to a high temperature. The important part that temperature plays is too often overlooked and many failures result from this neglect alone. The second essential is thorough emulsification of the mixture of fats, waxes, oils and water used, no matter what type the cream may be. On a small scale this can be obtained by constant and vigorous stirring or whipping with an egg beater, on a large scale an emulsifying machine must be used. Here, too, temperature is important, the mixture of fats, oils and water must not be hot, just hot enough to make all of the ingredients fluid and limpid. Too high a temperature delays emulsification and often causes separation of water from the cream on standing it in a cool place.
It should hardly be necessary to suggest that all materials used in cold creams must be of high quality and that they be tested for their suitability for the special preparation to be made. The melting point of waxes and fats should always be taken or ascertained, as this varies widely in fats and waxes of the same general type. Paraffin waxes especially have a wide range in melting point. In preliminary experiments with a formula for a cold cream always determine as carefully as possible the melting point of the solid fats or waxes used, then when a successful formula is worked out for a cream that stands up well, be sure that future batches have the same melting points.
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