_Average sales price of net resin, 1937 (per pound)_ Type of resin: Cast phenolic $0.41 Tar-acid: For molding .18 For laminating .13 For coatings .17 Alkyd .20 Urea .45 Because the cost of the filler is less per pound than the cost of the resin, the cost of the tar-acid and urea molding powders will be less than the figures given for the pure resin. On the other hand, wholesale prices paid by consumers will include transportation and distribution costs not included in the figures of manufacturers’ sales. Vinyl resins, acrylate resins, and polystyrene resins are at present produced in much smaller volume than those just listed. If and when the volume of production is increased the price may be decreased. In 1937, the price per pound of pure resin[12] was as follows: _Average sales price of net resin, 1937 (per pound)_ Type of resin: Vinyl $0.69 Acrylate 1.66 Early in 1938, acrylate resins were being offered for sale at 85 cents per pound for molding powder and $1.25 per pound for the cast material; polystyrene resins at 72 cents per pound. Petroleum resins, in 1937, sold for an average of 2 cents per pound net resin content.[12] This low price puts them beyond competition of the other synthetic resins in the uses in laminating and coating to which they are adapted. The physical properties of a resin and its uses. A more expensive resin will be used in preference to a cheaper one, only if the higher cost is more than offset by some physical property, such as color, which makes it more desirable in a particular use. The most common molding resin at present is the tar-acid type, but it is available only in the darker colors and therefore has been at a disadvantage, where a light color is desired, in competition with cellulose nitrate (celluloid) and cellulose acetate plastics or with urea and cast phenolic resins. In recent years the production of cellulose acetate molding compounds and of urea resins has increased rapidly, largely under this stimulus. The desire for color also promises well for the future of the acrylate and polystyrene resins which are produced in water-clear grades or colored with dyes or pigments. TABLE 17.—_Synthetic resins and other plastics: Properties that affect appearance_