THE ART OF THE PERFUMER 9.47 should not at times try to effect economy by introducing slightly inferior grades of these materials. This is sometimes done and it is a very unsound practice, for often the perfumer is then requested to prepare perfumes which will cover an unpleasant basic odour. This is very false economy because the perfumer cannot deodorise he can only offer a coverage which is some- times not successful and is always costly. The slight increase in cost of purer raw materials does so often mean that a slight decrease in perfume content can be effected which will then offset the extra cost. Not only should the ingredients be carefully controlled but the odour of the finished preparation has been spoiled very often by the odour of boxes or cartons. Preparations in glass bottles do not suffer from this, but care must be exercised that the closure is satisfactory. The packaging of cosmetic preparations in polythene bottles presents quite a different problem, and care must be taken to ensure that the constituents of the perfume in the preparation will neither attack nor permeate through the polythene. So many cartons and cardboard boxes possess an odour derived either from the board or from the glue used in sealing or sometimes even from the printing ink. Perfumes, too, will permeate these packages, and this can result in unpleasant odours not caused by the deterioration of the perfumes but from outside contact. It is therefore necessary to take the package as well as the raw cosmetic ingredients into consideration if a satisfactory preparation is to be marketed. When dealing with packages, those which have an un- pleasant odour should be investigated and the troublesome materials replaced if possible. Where this is not possible, the unpleasant odour of a package can often be removed by blowing a warm current of air over the package. Where this is not practicable then a light internal spray with a perfume similar to the one being used for the contents should be carried out and the package allowed to stand for a short while. Failing all this, it might be helpful if the finished packed preparation is lightly sprayed on the outside, for which a fine aerosol spray might well be useful. We are requested to provide a perfume for a whole range of products and this is a very difficult problem indeed. Having produced a satisfactory handkerchief perfume the perfumer must then have knowledge of all other preparations of the range. If possible, he should co-operate with the cosmetic chemist on the question of ingredients, but whether this is done or not, it is always desirable to "shelf-test" the perfumed products in an inert package and also in the package into which it is intended to be packed. An acceler- ated test can be run parallel to determine if there is any rapid deterioration, but products do sometimes show deterioration after an accelerated test, and I do not feel that a test of this type is conclusive enough. It is important to endeavour to produce some of the obvious conditions which the preparation may be called upon to endure, such as varying atmospheric conditions of different countries. From experience these have been the cause of the

248 JOURNAL .OF THE SOCIETY OF COSMETIC CHEMISTS following troubles in various preparations: the discoloration due to intense sunlight the attack on cardboard boxes and containers by a very humid atmosphere the precipitation in perfumes caused by intense cold. In creating a perfume the perfumer is not always required to provide a similar complex for a whole range of products, and in those instances where only a handkerchief perfume is required the problems are eased somewhat, but where a similar tonality is required for powders, creams, etc., then several factors must be taken into consideration, for example, discoloration and irritation in creams and the stability of a compound in an alkaline base. Face creams should be perfumed with a delicate fragrance. It must be borne in mind that the day creams are usually covered with a perfumed face powder whilst the night or deansing creams are removed after a short while. The oxidation of ingredients in powder preparations must be taken into account and those ingredients which oxidise readily should not be incor- porated into the perfume. Care should be taken not to use ingredients which will polymerise, and products which may affect the colour of a face powder must be eliminated. The latter does occur, although it is not a common feature of perfume in face powder. The action of strong alkalis such as bath salts creates quite a problem and often a fragrance is completely destroyed. Only perfumes of proved stability in this medium can be used, and care must be taken to ensure that there is no adverse effect on the colour. In lipsticks any component with a bitter taste must be eliminated and care taken not to include those aromatics which easily cause irritati6n. Although many aromatics are known to do this to a greater or lesser degree, quite a number' have been used successfully for some time in perfumes for various lipsticks without any declared ill effects. The perfuming of toilet soaps presents its own difficulties. To prepare a soap perfume the perfumer should be aware of the type of soap to be manu- factured, and whether it is to be a high-priced product or a cheap quality. Soap is used primarily as a cleanser and secondly as a beauty aid, and should therefore possess a pleasant fragrance. The perfume in soap must be noticeable and pleasing during its usage, and in most instances should leave a pleasant fragrance on the skin. The perfume should be consistent through the life of the tablet and not be changed by the mode of use. It is slightly less difficult to adapt an existing fragrance to suit a soap than it is with many other toiletries, if there is no objection to discoloration, although many components will be altered a little in odour by the influence on the soap base. Many aromatics are not stable in soap, and soap is affected by them, but the perfumer should be aware of the effect of various aromatics in soap and take the necessary precautions. If there is to be a complete disregard of aromatics that are not stable, discoloration in soap will have to be accepted, and that is one reason why so many soaps are coloured. The colour helps