Movies,
amateur roll films, color negatives and slides are still being produced
on cellulose acetate film which was introduced in 1925 by Eastman Kodak
to replace nitrate.*
Like
nitrate, this unstable film base created several preservation and
safety issues. As acetate
film deteriorates, acetic acid is released inside the plastic support
and gradually diffuses to the surface, causing a sharp vinegar-like odor.
Over a period of time the film base shrinks and the emulsion buckles. This
deterioration is greatly accelerated by poor storage conditions.
*Safety film was actually used as early as 1912 in the Edison Home Kinetoscope
-- a hand-cranked, arc-lamp motion picture projector designed and built
in Thomas Alva Edison's laboritories. The film for this projector was 22mm
wide, on produced on Eastman safety stock. |
