Educational Film Magazine (Jan-Jun 1919)

KODAK FILM IN THE MAKING Materials, Methods, and Processes Used in the Manufacture of Eastman Nitro-Cellulose Base and Sensitive Gelatine Emulsion — Quality as Well as Quantity the Watchword at Kodak Park By E. A. Hunger WITHOUT film the photographic industry would be a sorry pigmy beside the widely ramified industry that it is today, and well can we say that photographic film, both for still and motionpicture work as developed and made in the great Kodak Park Works, has helped enormously to place photography on the high plane that it stands today. In fact, it was due largely to George Eastman's efforts, begun back in the late eighties, that the film camera and the "movies" were made possible. At first the film had a backing of paper; and the development of this type of film and the so-called "stripping film" (the emulsion of which was so made that when placed in water it could be removed from the paper backing, dried, and then transferred to a transparent backing of gelatine) made the first kodak with the famed slogan, "You press the button, we do the rest," a possi' bility. Film with a paper backing was only temporary, however, for the great desideratum was film with a transparent base or support. After months of application the kodak engineers brought out a film with cellulose as a base, and then the series of developments which came as a result of the production of kodak transparent flexible photographic film in ever-increasing quantities revolutionized the photographic industry. Made Motion Pictures Possible The advent of the Eastman film proved a particular boon to motion pictures; in fact, the courts have decided that Eastman film made the complete commercial success of the motion-picture camera possible. With the continually growing popularity of motion pictures the demand for kodak film mounted higher and higher. Quality in those early days, as now, was of paramount consideration; but the company went further and made elaborate preparations for the future. It takes a great deal of time and money to prepare for the manufacture of photographic film of high average quality in the large quantities necessary for present-day production. To keep ahead of the demand and always be ready for big business as the Eastman Company has done requires vision and pluck — the vision to anticipate every demand and the pluck to spend millions of dollars as a toll for preparedness. Use 4,000,000 Silver Ounces Yearly The story about the making of kodak film is one of continuous interest. Many diversified products enter into its manufacture. Who, for instance, outside those in the "know," would think that bales and bales of cotton are required for the making of the thin transparent backing on which the light sensitive picture-making coating is spread? Or who would imagine for one instant that some two tons of silver bullion are used each week in the Kodak Park plant for making the sensitive coating? Two tons of silver a week! Think of it! Close on to 4,000,000 troy ounces a year, almost twice as much as the total output of the white metal from Arizona, one of the leading silver-producing states of the Union! When the sixteen-to-one idea fell into the discard in 1896, everybody said that the silver industry had irrevocably passed to the "bow-wows," but the many photographers throughout the world, together with the "movies," have helped bring it back with a mighty thud. Besides the silver and cotton, there are the various acids for treating these products, thousands of tons of which are required. Then come the organic solvents, including alcohol and other liquids, for converting the nitrated cotton into a honey-like fluid from which the thin film is made, and lastly the gelatine and chemical compounds for making the sensitive coating. For the convenience of analyzing the various steps taken in the manufacture of kodak film four general processes may be considered as follows: 1, chemical preparation of raw materials such as the cotton and silver already mentioned; 2, spreading of the support or cellulose backing for ■ the sensitive coating, which is called the emulsion, in thin layers on the surfaces of huge wheels; 3, spreading of the sensitive emulsion in a thin layer on the support; and, 4, slitting of large film rolls into stock sizes, inspection and packing for shipment. Quality and Clearness Essential Of course, in making anything that requires such a high degree of quality and refinement as photographic film, every process must be conducted in the cleanest of surroundings. High average quality is another important requisite in photographic film. It means that a photographer can get the same kind of good results at one time with one piece of film that he can with another piece 1. Weighing silver bullion. 2. Draining liquid in porcelain baskets from white silver nitrate crystals, room; silver bars are dissolved in nitric acid to form silver nitrate. 5. Washing cotton. 24 3. Cotton nitrating centrifugal. 4. Silver nitrating