Pyrex

Pyrex is a brand name for thermal shock resistant glass introduced by Corning Incorporated in 1915.

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The name PYREX

A Corning executive gave the following account to Mitford M. Mathews (American Speech, Vol. 32, No. 4. (Dec., 1957), p.290.)

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.

Composition

Pyrex was originally borosilicate glass. Though borosilicates had been produced before, the name Pyrex is widely used as a genericized trademark for the material. Corning spun off its kitchenware division in 1998 as World Kitchen, Inc. However, Corning retained the Pyrex brand name, licensing it to World Kitchen and other companies that produce Pyrex-branded cookware (e.g. Newell Rubbermaid's Newell Cookware Europe)^[1].

Pyrex kitchen products produced by World Kitchen are no longer made from borosilicate glass, but from soda-lime glass.^[2] Their packaging indicates that they must never be used over a flame, on stove tops, under a broiler, or in a toaster oven.^[2] However, Pyrex kitchen products made and sold in Europe by ARC International Cookware SAS (a subsidiary of ARC International Inc., a French manufacturer of crystal and glassware; including dinnerware, bakeware/ovenware, and stovetop pots) are still made from borosilicate glass, as stated by on their Pyrex website.^[3]

The brand in Europe, including Middle East and Africa, is now currently owned by ARC International Inc.^[4] who acquired the European business in early 2006 from Newell Rubbermaid who in turn had acquired it from Corning in the 1990s.^[5]

Safety issues

Recent reports suggest that due to the change in World Kitchen,Inc.'s manufacturing,^[2] notwithstanding the claims made for Pyrex, the glassware can shatter violently and unexpectedly, even when used in accordance with manufacturers' instructions.^[6] Claims have been made of severe personal injury during these events. The tendency to break into large pieces, rather than shatter like tempered glass, can produce large cutting edges capable of causing serious injury. Some reports have suggested that older Pyrex was not as susceptible to these problems as currently produced Pyrex. It is unknown whether this has anything to do with the recent change in ownership and location of manufacture of the Pyrex brand.  

Famous example of usage

Caltech's famous 200-inch telescope mirror at Palomar Observatory was cast by Corning during 1934–1936 out of Pyrex, which expands and contracts less than ordinary glass. Modern, commercially built reflector telescopes use Pyrex glass for the primary and secondary mirrors. It is harder to grind and more costly, but has advantages.

A demo

The 1950's television show Watch Mr. Wizard demonstrated the properties of Pyrex glass with an experiment that dazzled numerous children: two apparently identical glass bowls were placed on a slab of dry ice: one was identified as being Pyrex, that being the most common trademark for borosilicate glass at the time, and the other as being ordinary glass. Then Mr Wizard poured molten lead into each bowl. The Pyrex bowl held up well, and eventually the lead solidified. The ordinary-glass bowl cracked and broke into several pieces, and the molten lead ran onto the dry ice, causing a spectacular cloud of fog and loud hissing.

Cultural references

Pyrex pots are often alluded to in gangsta rap, the artists referring to the method drug dealers commonly use to prepare crack.^[7]

Surf-Rock band Man Or Astro-Man? had an instrumental track entitled, "The Miracle of Genuine Pyrex" on their 1000x EP. The song features a repeated sample of an austere man's voice speaking the line, "Research, experimentation, testing, more testing." This refrain suggests that the song is about the marvel of scientific progress, which yields many useful home products, including the titular Pyrex.

See also

• Bomex
• Kimax
• Cookware

References

• Rogove, ST; Steinhauer, MB (1993). Pyrex by Corning: A Collector's Guide. Antique Publications. ISBN 0-915410-94-X.