Higher-solids coatings for cars A new acrylic coating and a new acrylic resin, both with higher solids than usual, are now available for auto finishing. The result is a thicker film of paint or fewer spray stations, or a combination of the two. Jones-Dabney automotive division of Celanese Coatings Co. is offering a thermosetting acrylic coating with 20% higher application solids than conventional acrylic auto topcoats. Like other auto acrylics, the new coating uses a solvent system which complies with Los Angeles County's Rule 66 for controlling solvent emission. Archer Daniels Midland is supplying a high-solids, low-viscosity thermosetting acrylic resin. Now being evaluated by several of the major auto makers, the resin permits coatings with 30 to 50% more solids than acrylics now used by Detroit. Tradenamed Crylitex 4000, JonesDabney's new coating atomizes better than competitive acrylics and thus decreases orange peel appearance, according to the company. Also, it uses lower-cost reducing solvents. Previous attempts by paint makers at higher solids resulted in solids increases of 5% in metallic coatings (at application) and no more than 10% in nonmetallics. Crylitex 4000 gives at least a 20% increase in application solids contents. ADM's new resin—Aroset 4110-X60—gives paints which perform as well as or better than existing auto finishes, the company says. Application solids content of a typical metallic using conventional thermosetting acrylic resins is about 30% by weight. With ADM's resin, it would be about 40%. The resin requires only one solvent, xylol. Other auto paint suppliers, including PPG Industries' automotive finishes division, Cook Paint & Varnish, Du Pont, and Interchemical's finishes division, are also working on highersolids systems.
which is used in existing self-extinguishable ABS. Since it eliminates the need for flame-retardant coatings, the new ABS offers substantial economies in the injection molding of electrical products, such as computer parts and housings for business equipment, appliances, and power tools. Marbon foresees sales of 40 million pounds per year in five years. The new ABS also offers fast flow and easy processing. It can be molded in screw or ram machines between 380° and 490° F. Marbon doesn't recommend extrusion or prolonged exposure above 500° F. Since Cycolac KM contains no polyvinyl chloride, it is noncorrosive. Molds and screws need not be chromium-plated. It is stable and has high impact strength, the company says. Initial truckload price of the selfextinguishable ABS is 55 cents per pound, natural, and 59 cents per pound in colors. Marbon hopes to have it available soon in sheets. The ABS-polycarbonate alloy, Cycoloy 800, is the first of a series of ABS alloys to be sold under the Cycoloy name. Marbon isn't commenting on other alloys or on its source of polycarbonate for Cycoloy 800. The alloy combines the qualities of polycarbonate (high impact strength and heat resistance) and ABS (easy processing and lower price). It can be injection molded using screw machines, and it can be extruded into sheet for vacuum forming. Marbon has used Cycoloy 800 for helmets, hip pads, pump impellers, cable separators, golf-club heads, and food-serving dishes. The company hopes to sell about 13 million pounds per year of the new alloy by 1972.
Cycoloy 800 parts are very rigid and hard, Marbon says. The material passes the UL warp test at 212° F. and many other heat-distortion tests. It can also be accurately color-matched. However, it is not transparent or selfextinguishing. Introductory selling price of the new alloy is 77 cents per pound, natural, truckload. It is available in a full range of colors.
Instrument assays drug tablets An automated instrument designed to run content-uniformity assays on tableted pharmaceuticals will be sent this week to Ciba Pharmaceutical, Summit, N.J., from American Instrument, Silver Spring, Md. And during the week, Aminco's Thomas J. Slone, manager of instrument engineering, is scheduled to discuss the spectrophotometric system at the general instrumentation sessions of the annual ISA conference in New York. Ciba's unusual instrument was developed to provide tighter quality control for its tableted and encapsulated products. Unit dosage variation from one tablet to another is an important aspect of pharmaceutical production. While the drug producers commit themselves to ensuring product consistency, the Food and Drug Administration maintains content-uniformity requirements for certain tableted products. These requirements place heavy demands on the analytical chemist to assay replicate samples of batch production, says Ciba's Dr. Carl R. Rehm, associate director, analytical research section. Ciba not only recognized the economy of automating this quality-control
Marbon has new ABS plastics Two new plastics, a self-extinguishing acrylonitrile-butadiene-styrene thermoplastic and an ABS-polycarbonate "alloy," were introduced last week by Borg-Warner's Marbon Chemical division. The company expects combined sales of the two products to exceed 50 million pounds per year five years from now. Cycolac KM is both self-extinguishing and nondripping under the Underwriters' Laboratory flame test. However, Marbon will not say how the property is obtained. The new ABS doesn't contain polyvinyl chloride, 22 C&EN OCT. 24, 1966
Aminco's Assayomat Dispenses, dissolves, filters, dilutes, measures UV
effort but also wanted to obtain a system that provides increased amounts of statistical data on various aspects of product uniformity, Dr. Rehm says. For the past two years, Ciba and Aminco have developed the instrument to provide the versatility Ciba requires while retaining design adaptability to accommodate other drug companies' possible interests. The Assayomat can be programed to dispense a tablet, add solvent, sonically dissolve the tablet, filter the solution, dilute it to a preselected concentration, and measure ultraviolet absorbance. With this sequence, the instrument can assay up to 400 tablets at a maximum rate of 120 assays per hour. It can perform different analyses on as many as 20 different types of tablets. And since pharmaceutical production is generally done in batches of various products at the same time, this versatility has been designed into the system. A program card corresponding to each different procedure directs the instrument to follow the appropriate analytical program in a continuous, hands-off operation. Dr. Rehm estimates that about 80% of Ciba's 72 tableted products are amenable to programed analysis. In each of these cases, the active ingredient being assayed shows desirable solubilities and concentration sensitivities to UV absorbance. Common to the analyses of these tablets are only four variables: type of solvent; sonifying time for dissolution; concentration; and UV wave length. The instrument accommodates these variables and can thus be programed to carry out 20 different procedures. The tablet dispenser is a vertical stack of 20 circular trays, each of whose 20 tablets is assayed by the procedure of the corresponding program card. A preselected solvent in any one of five quantities is added to a dispensed tablet. A sonic transducer operating at 10,000 c.p.s. is lowered over the tablet, dissolving it in less than a minute. The solution is then filtered and transferred to a container or a conveyer belt for dilution. The diluent burets dispense one of three solvents in any one of five quantities. The solution is then drawn into a flow-through cell in the spectrophotometer for analysis. As one sample is being recorded, another is being diluted, and a third is being sonified, thus maximizing the Assayomat's output. An electronic programing system controls the electrical and mechanical operations of the Assayomat. Control is a closed-loop system with stepping switches programing sequence control and instrument variables. Ciba expects to spend several months incorporating the Assayomat
into its quality-control operation. Standard absorbance readings must be made on all the pure drugs while determining the most suitable solvents, concentrations, and wave lengths for each assay procedure. Furthermore, the results of the instrument will be correlated with those from standard laboratory methods to establish confidence and reliability in the instrument.
Nobel Prize to Rous, Huggins Dr. Francis Peyton Rous, the first man to discover a cancer virus, and Dr. Charles B. Huggins, the first to control a major type of cancer with chemicals, will share the 1966 Nobel Prize in Medicine. Dr. Rous, 87, pathologist at Rockefeller University in New York City, and Dr. Huggins, 65, University of Chicago professor of surgery, will each receive a gold medal and $30,000. This recognition has been a long time coming for the two veteran U.S. medical research scientists—especially for Dr. Rous. He is being cited for his 1910 discovery of a virus that invokes malignant tumors in hens. Dr. Huggins' selection for the prize is based on discoveries, dating back to the 1930's, concerning the use of hormones to treat prostate and other cancers. The medical faculty of Sweden's Royal Caroline Institute, which awards the medicine prize, points out that the significance of Dr. Rous' discovery has increased every year since the isolation of a leukemia virus in mice in 1951. The importance of the Rockefeller scientist's work has only been comprehended in the last decade. Discovery that the Rous virus can evoke tumors in many animals has started a trend in favor of the virus theory of cancer, which has long been neglected. Dr. Huggins' work in cancer therapy was triggered by his discovery, while doing experiments on dogs, that functioning of the prostate gland depends on production of androgens. This led to the discovery that female sex hormones can control cancer of the prostate. Dr. Rous received his M.D. from Johns Hopkins in 1905. He spent the next year in residence at the same school. After two years as instructor in pathology at the University of Michigan, he moved to Rockefeller. Dr. Huggins received his M.D. from Harvard University in 1924 and interned at the University of Michigan for the next two years. He then became one of the original faculty of the University of Chicago medical school. In 1951 he also became head of the university's Ben May laboratory for cancer research.
Dr. Charles B. Huggins Cancer control
Dr. Francis Peyton Rous Cancer cause
Canada forms Ch.E. society Chemical engineering has a new voice in Canada. It was heard for the first time last week in Windsor, Ont., where the 16th Canadian Chemical Engineering Conference took place under sponsorship of the newly formed Canadian Society for Chemical Engineering. Previously, the conference had been sponsored by the Chemical Institute of Canada, the new society's parent. CIC, at its annual conference (held in Saskatoon in July), announced ratification of bylaw changes making the new chemical engineering society possible. From CIC's formation in 1945 until now, chemical engineering had been a division of the institute, becoming in later years its largest. CSChE will operate as a constituent OCT. 24, 1966 C&EN 23
