george eastman introduced the flexible film to the market.
george eastman introduced the flexible film to the market.
who introduced the flexible film to the market?
george eastman
early motion picture experiments in the 1880s were performed using a fragile paper roll film, with which it was difficult to view a single, continuously moving image without a complex apparatus. the first transparent and flexible film base material was celluloid, which was discovered and refined for photographic use by john carbutt, hannibal goodwin, and george eastman. eastman kodak made celluloid film commercially available in 1889; thomas henry blair, in 1891, was his first competitor. the stock had a frosted base to facilitate easier viewing by transmitted light. emulsions were orthochromatic. by november 1891 william dickson, at edison's laboratory, was using blair's stock for kinetoscope experiments. blair's company supplied film to edison for five years. between 1892 and 1893, eastman experienced problems with production. because of patent lawsuits in 1893, blair left his american company and established another in britain. eastman became edison's supplier of film.
film stock
vacuum bag moulding uses a flexible film to enclose the part and seal it from outside air. vacuum bag material is available in a tube shape or a sheet of material. a vacuum is then drawn on the vacuum bag and atmospheric pressure compresses the part during the cure. when a tube shaped bag is used, the entire part can be enclosed within the bag. when using sheet bagging materials, the edges of the vacuum bag are sealed against the edges of the mould surface to enclose the part against an air-tight mould. when bagged in this way, the lower mold is a rigid structure and the upper surface of the part is formed by the flexible membrane vacuum bag. the flexible membrane can be a reusable silicone material or an extruded polymer film. after sealing the part inside the vacuum bag, a vacuum is drawn on the part (and held) during cure. this process can be performed at either ambient or elevated temperature with ambient atmospheric pressure acting upon the vacuum bag. a vacuum pump is typically used to draw a vacuum. an economical method of drawing a vacuum is with a venturi vacuum and air compressor.
composite material