Kodak reports on: how to overcome boredom with polyethylene, • a mask for glass, switched by light. strange dances in the movies
Colloquy on floor polish One man's poison is another man's meat, the millstone around one man's neck becomes the keystone in another's arch. Take floor polish. There must be quite a few chemists who have worked, slept, and eaten floor polish for so long that they know all there is to be known about it and feel trapped by the subject in a boredom most piteous. Then along come you, fresh-faced and full of fun and optimism. What, you ask, do they put in floor polish? Polyethylene. Have they always put in polyethylene? No. Would it be fair to state then that, seen from the long vista of floor-polish history, one currently finds oneself safely over the threshold into the polyethylene era? Yeah. Does this differ from the familiar polyethylene? How? Through molecular weight frequency distribution, degree of branching, and percentage of hydrogens oxidized to hydroxy Is, you pick your density, hardness, viscosity-temperature behavior, and emulsifiability. How is emulsification effected in water of a solid like polyethylene? With emulsifiers. Most floor polishes have used anionic emulsifiers like oleic acid-morpholine. Hard to keep them light in color. Amine-type cationic emulsifiers have also been studied. But the non-ionics look the most promising. And that goes, too, for polyethylene emulsions used to modify the finishing resins for wash-and-wear cotton goods. Restore strength to the cotton and improve its sewability. See here. If you find this so all-fired fascinating, that could mean you see a commercial angle. It could become vital for us to get to know you better right away. If only you would disclose your name,, address, and interest in the topic to Eastman Chemical Products, Inc., Kingsport, Tenn. (Subsidiary of Eastman Kodak Company), a kit of information on our Epolene polyethylenes and their emulsification will become the initial token of our common intellectual interests.
An invitation to engrave Etching is, of course, not the only way to dig into a glass surface. With sufficient patience and skill a grinding wheel yields superb results. If time flits too rapidly for that sort of monkeying around, you coat a resist over your surface, scribe through it, and let the H F go to work. In case the pattern is intricate, or needs to be repeated, or both, you want a photosensitive resist. Then you can draw up the pattern once, nice and big and black, reduce it photographically onto a Kodalith material and use the resulting photograph as a mask which determines where the resist comes off and exposes the naked glass to H F . Think a moment what you are asking of any photosensitive resist. It must be capable of being switched by a reasonable amount of light from one to the other of two conditions: a) tenacious adherence to the particular material you wish to etch and impenetrability to agents which rapidly attack that material; b) abject submission to attack by agents which do not affect the substrate, or alternatively, full permeability to appropriate etchants for the substrate. Obviously, we have given this matter much more than a moment's thought. Our researches have now brought forth a photosensitive resist for glass and silicate ceramics to join our previously announced Kodak Photo Resist ("KPR," for copper, clear anodized aluminum, and high-copper alloys) and Kodak Metal-Etch Resist ("KMER," for other metals). We would be justified in trying to recover all that thinking expense by selecting a similar proprietary name to imply the
discovery of a new chemical compound but have decided on a cleverer course— We shall have you buy Kodak Metal-Etch Resist and tell you how to convert it to a glass-etch resist by the use of those two arcane compounds, technical-grade aluminum stéarate and sulfur-free xylene. For details, write Eastman Kodak Company, Graphic Reproduction Division, Rochester 4, Ν. Y. If you don't want to bother stating your problem, just say "photosensitive resists.""
Favor for the high-speed congress Dust Performs for Plant's Pollution-Control Movies, Chem. Week, 84:84, 86, May 2, 1959. (The Procter and Gamble Company uses high-speed motionpicture sequences for the qualitative control of in-plant dust.) The Ignition of Explosives by Radiation, J. Eggert, / . Phys. Chem., 63:11-15, Jan., 1959; also in Photochemistry in the Liquid and Solid States, edited by F. Daniels, J. Wiley, Ν. Υ., 1960, pp. 147-53. (High-speed photography proves that the detonation of nitrogen iodide starts before the light flash ends, show ing that only a fraction of the energy is used for the detonation.) Lathe Check Formation in Douglas-fir Veneer, Ε. Η. Collins, Forest Products /., 10:139-40, March, 1960. (High-speed motion pictures were used by Weyer haeuser Company to analyze production variables.)
Time after time we have visited a customer proud of some accomplishment with high-speed movies. He is willing to show us—eager, delighted to show us. The projector is started and we watch. We see a collection of strange objects. We don't know for sure what they are. Little seems to be happening. After quite a while, a new object enters the scene from the left. Shortly another new object comes up from the bottom. The two dance around each other, touch, and exit from the top of the frame. All is again static on the screen. After another while the reel comes to its end and we jump to our feet exclaiming hearty congratulations. He deserves congratulations, probably. If we had lived with the problem as he has, the objects in the picture might have seemed no stranger than the face in the bathroom mirror; the dance might have been the triumphant, forceful, sudden, undisputed clincher to a vexatious problem; the en thusiasm of the born salesman might have meant more. Nevertheless, we need not be ashamed. We help scientists and engineers use high-speed photography by manufactur ing a group of films to the stringent mechanical require ments of high-speed cameras. Kodak Plus-X Reversal Film we make for reversal processing to a fine-grain positive. Kodak Tri-X Reversal Film is four times as fast. Kodak Double-X Panchromatic Negative Film, which is a bit faster yet and very sharp, is picked when a quick negative will suffice or when several prints may be wanted later. Kodak Royal-X Pan Recording Film is picked only when light is very limited indeed; Kodak Linagraph Ortho Film, for ac centuated sensitivity to green light; Kodak High Speed In frared Film, for sensitivity to 9000A, with a maximum from 7700A to 8400A; Kodachrome Film, for color, with low-cost commercial processing widely available; Ektachrome ER Film, for color at exposure index of 160 or higher. Another thing. A bibliography on high-speed photog raphy. Every item our library knows. Coverage extends into 1960. Got it ready to distribute to the Fifth International Congress on High-Speed Photography in Washington in October. Doomed to a short life, since the Congress promptly generated so many new papers on high-speed photography that the abstracts alone run from p. 609 to p. 682 of the September, 1960, issue of the Journal of the Society of Motion Picture and Television Engineers. Eastman Kodak Company, Photorecording Methods Division, Rochester 4, Ν. Υ., would be glad to send the bibliography or answer ques tions about the above-named films, J^k
This is another advertisement where Eastman Kodak Company probes at random for mutual interests and occasionally a little revenue from those whose work has something to do with science
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