MODERN LIPSTICK BASE MANUFACTURE 523 This process is repeated with every individual pigment used in the lipstick colour range. The result is a series of very good individual colour dispersions in castor oil. To obtain them, however, there has been a lot of handling of drums and cumbersome ball mill chambers, whilst the amount of cleaning created is phenomenal. The cleaning is also of a type which makes it impracticable to use a bath of any sort and thus reduce its drud- gery. Stage II--Preparation of the wax blend The solid constituents of the formula are weighed out into a steam pan, melted and mixed. The blend is drawn off by bucket, and then cast into slabs. Stage III--Preparation of the oil blend The various oily materials of the formula, except for castor oil, are weighed into a suitable tank, mixed, and the blend is pumped into drums for storage. The foregoing three components, together with perfume and further castor oil are mixed, as indicated by the flow diagram shown in Fig. 2. Stage IV--Preparation of the lipstick base Because the pigments are stored in suspension, they must be stirred up before being weighed out in the right proportions for the shade being made. The mixture of colours is then stirred together and passed through a colloid mill. In the meantime, the wax and oil blends together with further castor oil are weighed, heated and stirred together until homogeneous. The colour dispersion is then added, thoroughly mixed and then the lipstick is tested for shade. Finally, the perfume is added, and the mass is drawn off by bucket and cast into trays for storage. DISCUSSION OF METHOD I When reviewing any manufacturing process from the operational viewpoint, we should ask ourselves the following two questions:-- (a) Are we doing unnecessary work? (b) Are we doing necessary work in the easiest way? If the answer to (a) is 'yes', and to (b) 'no', the progressive company

524 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS S t_._qa ge.__•__.• Weigh Weigh Stir I Colloid mill Steam pan wit• , Cast into trays Figur• • Preparation of lipstick base--Method I faces the facts of the situation and invests sufficient capital to rectify matters, knowing full well that dividends will accrue in the way of higher output and quality with fewer mistakes. Looking at Method ! from the standpoint of these questions, we must first of all try to find a replacement for the ball mill which is a batch machine of high weight and low capacity and as already pointed out, very difficult to clean colour dispersion, however, is the most important part of