CHEMICALS
New Dry Cleaning Solvent System Under Field Test Perchloroethylene-based solvent system contains detergent, additives Dow Chemical is now testing a new solvent system which may improve the control and efficiency of automatic dry cleaning processes. It may also eliminate some of the solvent maintenance chores now carried out by equipment operators. Maintaining the desired charge of detergent in the solvent has been a persistent problem in automatic dry cleaning operations, since, with conventional systems, detergent and solvent are handled separately. The new Dow system is a formulation of detergent, other additives, and perchloroethylene solvent. It is designed so that the desired detergent charge is obtained automatically by keeping the fluid volume at a specified level in the machine. This eliminates both the separate addition of detergent and the difficulties of detecting when this addition should be made. Market. The increasing volume of perchloroethylene imports may have added impetus to Dow's efforts in this field. Domestic production in 1962 was about 320 million lb. However, imports have risen steadily— from 30 million lb. in 1961 to 47 million lb. in 1962, and up to 38 million lb. for the first six months of 1963. Domestic price of perchloroethylene is 12 1 / 2 cents per pound; imported material sells for about 10 to 15% less. Dow's capacity is rated at 120 million lb. per year. But this figure is flexible, since plants can be readily switched from the production of perchloroethylene to trichloroethylene and other chlorinated solvents. Dow's major plant is at Freeport, Tex. Other plants are at Plaquemine, La., and Pittsburg, Calif.
COIN-OP TEST. Dow tests its new perchloroethylene solvent system in its research laboratories with dry cleaning equipment used by coin-ops, the initial market Dow will aim at after field tests, which started last June, are completed
About 90% of perchloroethylene consumption is for dry cleaning, the remainder mainly for metal degreasing. It shares the vast bulk of the dry cleaning solvent market with Stoddard solvent, a petroleum fraction. Dow's perchloroethylene business amounts to about $13 million per year. Field Program. The new solvent system is currently being field tested. The tests, which started in June and will run for a year, are being conducted in Norge machines at 12 locations around the country. If they are successful, the system will be commercially available in 1964. Dow's initial effort is directed toward the owners of the nation's 8000 coin-operated dry cleaning establishments. There appear to be two main reasons for this. These plants possibly need the most help; many of them are not operated by experienced dry cleaning personnel, and there has been considerable variation in the quality of service offered to the public. Also the coin-op business presents a relatively uniform field in which to test and develop a new product. Most coin-op machines are of generally similar design and all have been built since 1959. On the other hand, commercial units range from brand new machines to 30-year veterans. Formulation.
T h e n e w solvent sys-
tem consists of Dow's high-purity perchloroethylene (Dow-Per) with an added blend of detergents, antistatic agents, and surfactants. Dow will give no details of these additives. Some of the knowledge gained in the company's fabric conditioning research laboratory has been incorporated in the new system. Use of the new solvent will not require changes in existing dry cleaning equipment. The success of the system will depend on detergent and solvent being used up at parallel rates so that an acceptable balance is maintained between them in the machine. As the level drops, more new solvent can be added. This will replenish the solvent and detergent in one operation. Dow admits that this is something like walking a tightrope. But they are confident it can be done. It will be necessary, however, to run the test for a full year for evaluation under seasonal changes. The company predicts that the cost of the new system may be less than that of the solvent and detergent combination now in use. If successful, Dow plans to expand the new system into the commercial dry cleaning field. This approach will mean no major equipment investment for Dow, since it will involve only an additional blending process. NOV.
2 5, 1963
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