06-04-2017, 12:36 PM
(This post was last modified: 06-04-2017, 12:37 PM by peter scott.)
"After Corning Glass Works introduced Pyrex in 1915, the name became a synonym for borosilicate glass in the English-speaking world. However, borosilicate glass is the name of a glass family with various members tailoring completely different purposes. Most common today is borosilicate 3.3 glass like SCHOTT Duran and Pyrex by Corning.
The European manufacturer of Pyrex, Arc International, uses borosilicate glass in its Pyrex glass kitchen products;[1] however, the U.S. manufacturer of Pyrex kitchenware uses tempered soda-lime glass."
I'm not sure when Corning first licenced European manufacturers to use the Pyrex brand name but I rather suspect that Corning themselves were the principal player in the manufacture of these EMI tubes.
Etched onto the glass of the later tubes with the moulded face plates there is a reference to a British patent application 25246/36 that leads to GB470885A. This patent describes the process of using a moulded screen attached to a blown envelope and was granted to Corning Glass Works, Walnut Street, New York. I don't think there is a US version of this patent.
Peter
The European manufacturer of Pyrex, Arc International, uses borosilicate glass in its Pyrex glass kitchen products;[1] however, the U.S. manufacturer of Pyrex kitchenware uses tempered soda-lime glass."
I'm not sure when Corning first licenced European manufacturers to use the Pyrex brand name but I rather suspect that Corning themselves were the principal player in the manufacture of these EMI tubes.
Etched onto the glass of the later tubes with the moulded face plates there is a reference to a British patent application 25246/36 that leads to GB470885A. This patent describes the process of using a moulded screen attached to a blown envelope and was granted to Corning Glass Works, Walnut Street, New York. I don't think there is a US version of this patent.
Peter
