http://historyhole.com/brownie-wise-tupperware-house-parties-and-female-empowerment/
Before inventing Tupperware, Earl Tupper was a subcontractor for DuPont’s plastics war production. In the 1940s, he began experimenting with polyethylene with the intention of creating a commercial product. In 1947, Tupper invented what we now know as Tupperware: “an airtight, watertight” lid and a container made of “a tough, nonporous, and nonsmelling substance.”
http://search.proquest.com.ezproxy.umw.edu/docview/503181662?accountid=12299