[danelectro]

Polycarbonate bottles were not in widespread consumer use back in 1970.

Even though this particular polymer was originally discovered over 100years ago, and relatively modern production techniques were patented in the '50's, widespread use to replace glass in "water cooler" type bottles did not begin until the '80's.

Later this polymer moved down the chain into smaller bottles.

The invention of polycarbonate at GE in the '50's is interesting:

"[Fox's] discovery, made within eight months of his joining GE, was a serendipitous byproduct of the wire enamel project. The byproduct would prove far more important than the original objective."

from "Unlikely Victory: How General Electric Succeeded in the Chemical Industry"

http://books.google.com/books?id=bgdvYy80AHUC&pg=PA71#v=onep...