Pyrex is a brand name for glassware, introduced by Corning Incorporated in 1915. Originally, Pyrex was made from thermal shock resistant borosilicate glass. In 1998, Corning sold its consumer products division which subsequently adopted the name World Kitchen. Pyrex kitchen glassware is now made of tempered soda lime glass. Pyrex laboratory glassware is still made of borosilicate glass
A Corning executive gave the following account of the etymology of the Pyrex brand name:
The word PYREX is a purely arbitrary word which was devised in 1915 as a trade-mark for products manufactured and sold by Corning Glass Works. While some people have thought that it was made up from the Greek pyr and the Latin rex we have always taken the position that no graduate of Harvard would be guilty of such a classical hybrid. Actually, we had a number of prior trade-marks ending in the letters ex. One of the first commercial products to be sold under the new mark was a pie plate and in the interests of euphonism the letter r was inserted between pie and ex and the whole thing condensed to PYREX.
According to the National Institute of Standards and Technology, borosilicate Pyrex is composed of (in weight %): 4% boron, 54% oxygen, 3% sodium, 1% aluminium, 38% silicon, and less than 1% potassium.
According to glass supplier Pulles and Hannique , borosilicate Pyrex is made of Corning 7740 glass, and is equivalent in formulation to Schott Glass 8830 glass sold under the "Duran" brand name. The composition of both Corning 7740 and Schott 8830 is given as 80.6% SiO2, 12.6% B2O3, 4.2% Na2O, 2.2%Al2O3, 0.04% Fe2O3, 0.1% CaO, 0.05% MgO, and 0.1% Cl.
Pyrex kitchen products in Europe made and sold by a subsidiary of ARC International tableware company are made from borosilicate glass..
Corning's first attempt was a failure, the cast blank having voids. Using lessons learned, Corning was successful in the casting of the second blank. After a year of cooling, during which it was almost lost to a flood, in 1935 the blank was completed. The first blank now resides in Corning's Museum of Glass.
Pyrex's ambitions: Ray Gunderson explains how a 90-year old cookware brand, a favourite of grandmothers, reinvigorated itself to appeal to aspiring foodies across Europe.(Brand Papers)(Newell Rubbermaid Inc.)
May 01, 2004; The Pyrex brand has been around for 90 years and become synonymous with functional, durable glass cookware--most consumers...