In 1933, Ralph Diley was trainee at the laboratory Dow Chemical. It cleaned glassmaking after tests but a deposit formed on a test-tube resisted to him, impossible to eliminate it. It had just discovered the chlorinated polyvinylidéne (PVdC), copolymer connected with the PVC, but to which its long molecules give an incomparable resistance to solvents or acids and excellent impermeability with the steam or oxygen (comparable with the EVOH).

Some installations allowed to the researchers Dow Chemical to make of it a military, green material dark, Saran® (in remembering the inventor whose girls prénommaient Sarah and Anne) to protect the parts from plane of marine corrosion on the aircraft carriers. Post-war period, Dow came to end from its unpleasant odor and its color to give to PVdC food approval. It was rather easy to extrude it out of film and as it had the characteristic to stick spontaneously about on all, including on itself, Dow imagined to market it like first stretchable film, for industrial use in 1949 domestic then in 1953. It became the first product of the group intended for the consumer, under the name of Saran Wrap® which is still the generic name given to the the United States for the domestic spools.

When in their book “the 2000 year old man” Carl Reiner asks Mel Brooks to indicate the greatest invention of the history of humanity, this one answers “Saran Wrap”.

Since, it was discovered that other materials make it possible films to become sticking: the Polyethylene additivé, PVC plasticized for example. They are less expensive than films containing PVdC and barrier of this material they do not miss the characteristics since they act only in the protection of food and not their conservation. One locates about the years 1960 the starting of stretchable films for food contact, transparencies and powerful, containing PVC then at the Eighties those containing polyolefins. It is Goodyear which launched PVC stretchable film, plasticized, but only one production site remains under the mark of the manufacturer of tires with Sao Paulo with the Brésil.

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