In 1933, Ralph Wiley, a Dow Chemical lab worker, accidentally discovered polyvinylidene chloride or Saran. Ralph, a college student who cleaned glassware in a Dow Chemical lab, came across a vial he couldn't scrub clean. He called the substance "eonite", after an indestructible material in the comic strip "Little Orphan Annie." Dow researchers made Ralph's "eonite" into a greasy, dark green film, which Dow called "Saran". The military sprayed it on fighter planes to guard against salty sea spray and carmakers used it for upholstery. Dow later got rid the of Saran's green color and unpleasant odor.
After World War 2, it was approved for food packaging, and it was Prior Sanctioned in 1956 (Society of the Plastics Industry). PVDC is cleared for use as a food contact surface as a base polymer, in food package gaskets, in direct contact with dry foods, and for paperboard coating in contact with fatty and aqueous foods.
After World War 2, it was approved for food packaging, and it was Prior Sanctioned in 1956 (Society of the Plastics Industry). PVDC is cleared for use as a food contact surface as a base polymer, in food package gaskets, in direct contact with dry foods, and for paperboard coating in contact with fatty and aqueous foods.
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