SOME CURRENT PROBLEMS IN TOILET SOAP MANUFAGTURE By JAMES BATHER* IT WAS the Roman historian, Pliny, who stated that the Gauls were the original inventors of the art of soap- making, which they introduced into Italy after their successful invasions of Gaul. Goats' fat and the ashes of the beech tree were the essential ingredients of the epoch, while the subject of odour appeared only to have received attention at a much later period. Prior to the invention of soap, the ancients employed plant fibres and juices of a detergent nature, as well as various types of silica such as fuller's earth, which was rubbed upon the skin and clothes as a means of absorbing grease. The Mediterranean nations em- ployed fuller's earth even up to the beginning of the eighteenth century as a cleansing medium in the bath. In the eighth century, soap was made chiefly in Italy and Spain, and it is somewhat remarkable that nearly five hundred years elapsed before soap making was introduced into France by the Phoceans, a mixed but talented race of Grecian and Egyptian origin. Marseille was the chosen city for the introduction of soap into France, *Consulting Chemist and Perruiner, London. 226 owing to the facilities afforded of obtaining olive oil, and a crude soda ash obtained by calcination of various maritime plants, both of which pro'ducts were to be found in great abundance along the shores of the Mediterranean. .•' The exact period at which soap was first produced 'in England appears obs'cure, although it is 'frequently given as the fourteenth century, when it was made upon the French system. The first British ß Patent referring to soap manufacture"i was taken out in 1622 under the. title of Castile Soap by Messrs. ß Jones and Palmer, who claimed a process of making hard soap without:ß, the aid of heat. From this period up' to the present time, however, soap: patents must run into hundreds ofi• thousands, this being one of the most. :111, i prolific subjects treated in the patent lit erature. For an unduly long period art of soapmaking was empiricM?i and real progress was made after the invention of Leblanc's:i?'•i process for the manufacture of soda?? from common salt, which was developed by James Mudpratt St. Halens, a then small town in the? heart of industrial Lancashire. The!i•j truly scientific production of soap_?i

SOME CURRENT PROBLEMS IN came into being through the of Chevreul, another French of Leblanc, who raised the of soapmaking from the rule of method to something that be predicted from the specific ,.action that actually takes place. from this period onwards to have been fairly rapid and ?•ffiany new fats, oils and additives .iWere introduced. i?It must be admitted, however, that ?søapmaking remained a relatively ii:Backward industry until about half ?a century ago, for the so-called •- .... . •i:• prachcal bus•ness man" remained •i:Supreme, scorning the aid of science •ii'.!!0r even the assistance of a works ?•...:!!:chemist. A classic example 'of i(}:•:.'inefficiency due to such ignorance :• •.was the. failure for many years to ,•,•-' recover all or even part of the avail- ::i':•!:able glycerin. Many other wasteful ¾.,procedures were common practice •i• at this epoch. It is fortunate that ?)managerial and technical staff now }Work in much greater harmony, :i':il although a few factory owners still ½iexist (notably in undeveloped coun- :: :tries) who cannot refrain from ß ß (attempting false economies in plant :):land process control, technical investi- ?. :'gation and research. , SOME CURRENT PROBLEMS :11:: A subject of particular interest to manufacturers of toilet soaps at the •! present time is what may conveni- ::'ently be termed "the economics of soap perfuming." The devising of an attractively odorous perfume compound for soaps is much more difficult than is gener- TOILET SOAP MANUFACTURE ally supposed and the pitfalls are many. Of course, all perfume com- pounds call for skill in their invention and production, but more contribu- tory causes produce failures when one is dealing with soaps. Stability and fixation are the two main features to consider. To choose any floral compound and "hope for the best" when incorporating into a soap base is both illogical and most uneconomical, many such compounds giving disappointing results, with a veritable disaster upon ageing. One of the main causes is the erroneous view taken about perfume base costs, it being far cheaper to use less of a relatively expensive base than much more of a cheap base. In many cases the use of cheap perfume bases may be regarded as the direct cause of unsuccessful results, and a final product that has no popular appeal. Cheap soap base perfumery com- pounds frequently contain various residual terpenes these may, how- ever, from an odour point of view, be regarded merely as diluents of no value. This general, although incorrect, method of compounding a soap perfume, should be discarded in lavour of the method which requires that a base is first s•lected, which contains a definite odour value with a known stability in soaps, and that to this base other ingredients are added to build up a suitable odorous compound that is not affected when incorporated in the soap base. Volatility, stability and boiling range are the three main points to con- sider when choosing your ingredients, 227