| a glass containing 5 percent or more of B2O3, highly resistant to heat and shock, used esp. in making cookware and chemical glassware. |
| borosilicate glass n. A strong heat-resistant glass that contains a minimum of 5 percent boric oxide. |
borosilicate glass
(trademark), a type of glass and glassware that is resistant to heat, chemicals, and electricity. It is used to make chemical apparatus, industrial equipment, including piping and thermometers, and ovenware. Chemically, Pyrex contains borosilicate and expands only about one-third as much as common glass (silicate) when heated. As a result, it is less apt to break when subjected to rapid temperature changes. It is resistant to many chemicals and is an electrical insulator. Fibres and fabrics made of it possess excellent heat insulation and fire-resistant qualities. It is sometimes referred to by the generic term, borosilicate glass.
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