JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS The introduction of white oils came just before the turn of the century. Liquid paraffin was first introduced in the British Pharmacopceia in the 1898 edition. About 1887, a Russian chemist, J. Markownikoff, devised a process for the manufacture of white oils from Russian crude or distillate, and eight years later an oil refinery, specialising in white oils, was started at Riga, at that time in Russian territory. The refinery was under the name of Oelrich & Co., and it apparently kept going in spite of wars intervening until about the 1930's. It is solely because of this Russian origin that white oils came to be known as Russian oils in fact, even to-day the name still sticks in one or two isolated cases. The manufacture of white oils quickly spread westward to such places as Germany, Belgium and France, and up to the outbreak of the first world war there were probably half a dozen such refineries processing Russian distillates shipped from the Black Sea into white oils. America, up to a few years before 1914, imported all its white oil requirements from these refineries and, of course, so did this country. The 1914-1918 war put a stop to all exports from Europe and so the United States went ahead with its own production, until to-day its production capacity takes good care of all domestic require- ments and even leaves room for exports. It should be mentioned here that the demand for the so-called "Russian" oils from America did not die out until 1939, although up to that time the demand was getting smaller and smaller, year by year. In England, a small refinery was built at Snodland in Kent during the 1914-1918 war, and that ran for a few years before closing down some time in the late 1920's. There was also a very small plant introduced in Tottenham or Edmonton, under the guidance of a specialist, believed to be of Russian birth, who was certainly responsible for increasing the popularity of the use of white oils. However, that plant closed down after a few years and the United Kingdom had to rely on imports from a number of countries, Ger- many, France, Belgium, Holland and America being the main suppliers. In 1938 a refinery was started in the North of England to make such oils, and thus to assist in the national economy and strategy at a particularly opportune time. To-day, in 1955, the picture has completely changed. Other refiners have started here in this country, and there is now an adequate capacity to satisfy not only the demands of the home market, but to meet a large and ever- growing export market. The advantages of home production of white oils to the cosmetic and to other industries are obvious. White oil production is a highly skilled and scientific job. Quality control and consistent supply are of vital importance in all industries, and not the least of the advantages is the fact that the white oil producer and the user can pool their research and development work to produce a tallor-made product for the particular application. The impor- 246

WHITE OILS tance of this co-ol•eration cannot be over-emphasised experience ha• shown its value in many instances throughout the numerous industries using these highly refined oils. The basic or physical properties of white oils were at one time determined by the type of crude oil employed. For example, a naphthenic crude oil yielded a white oil of high gravity and viscosity, whilst a paraffinic crude gave white oil of lower gravity and viscosity. Although that was the case in years gone by, when Markownikoff started his researches, to-day the science of modern petroleum refining is such that the type of crude does not play so important a part in the finished product. In the same way, the constitutional analysis of petroleum products has made enormous progress in the last few years and is continuing to progress, like all scientific methods. It is not appropriate in this short review to go into the details of the methods of production of white oils the technique varies somewhat accord- ing to the type of crude selected and the final product required. Broadly speaking, the refining methods involve the use of sulphuric acid or oleum to remove all the unsaturated, aromatic and hydro-aromatic hydrocarbons. In other words, the unsaturated hydrocarbons are regarded as impurities which must absolutely be removed from the oil. This is a very expensive process, not only because of the amount and value of the chemicals used, but also because of the losses of oil during refining. The chemically treated and neutralised oil is then washed and filtered and "polished," and at all stages a very careful control must be exercised to ensure a correctly finished product. Even when the finished product is obtained that is, when the plant process engineer has received approval from the control laboratory, the oil is most carefully handled to preserve its particular characteristics right up to the user. That can amount to, say, a 16-oz. bottle of liquid paraffin BP that may or may not have been displayed in a chemist's shop for many weeks before it is sold to the final consumer. The care and attention paid to medicinal liquid paraffin applies equally to all grades of white oils and their compounds. Before enlarging on this very brief indication of the technique and care required to produce satisfactory white oils, it may be interesting to examine some of the uses to which wkite oils are put in order to have a better measure of the need of control at all stages to ensure the particular characteristics required. The uses of white oils are so extensive that no single person can be aware of them all, and therefore anything said on this aspect should not, by any means, be accepted as comprehensive. Further, it will be seen that the uses or at least quite a large percentage of them call for special skill and knowledge of quality and particular applications. Among the more conventional uses are those of the cosmetic industry and of the pharmaceutical industry. In the latter, the oils are used as internal 247