Ion exchange-strengthened silicate glass filter for ultraviolet light
First Claim
1. An ion exchange-strengthened silicate glass made from a glass making batch in which each 100 parts by weight on an oxide basis consisting essentially of:
- about 64 to about 75 parts silicon dioxide, about 5 to about 10 parts potassium oxide, about 4 to about 8 parts sodium oxide, about 4 to about 8 parts calcium oxide, and about 2 to about 10 parts cerium oxide.whereby upon ion exchanging at a temperature either above or below the strain point of said glass in a bath comprising salts of potassium and silver said glass provides an impact-resistant glass filter for ultraviolet light having a wavelength below about 400 nanometers and wherein said filter is transparent to light having a wavelength about 400 nanometers.
7 Assignments
0 Petitions
Accused Products
Abstract
There is provided by the process of the invention a silicate glass which provides protection against mechanical hazards and short and long wavelength ultraviolet radiation while at the same time high transmission of light in the visible range of the spectrum is maintained. By the process of the invention, the incorporation of cerium oxide into the glass followed by ion exchange strengthening using a mixture of potassium salt and silver nitrate provide a synergistic reduction in transmission of light in the ultraviolet range of the spectrum not heretofore obtainable by the use of either cerium oxide or silver staining of the glass alone.
-
Citations
8 Claims
-
1. An ion exchange-strengthened silicate glass made from a glass making batch in which each 100 parts by weight on an oxide basis consisting essentially of:
-
about 64 to about 75 parts silicon dioxide, about 5 to about 10 parts potassium oxide, about 4 to about 8 parts sodium oxide, about 4 to about 8 parts calcium oxide, and about 2 to about 10 parts cerium oxide. whereby upon ion exchanging at a temperature either above or below the strain point of said glass in a bath comprising salts of potassium and silver said glass provides an impact-resistant glass filter for ultraviolet light having a wavelength below about 400 nanometers and wherein said filter is transparent to light having a wavelength about 400 nanometers. - View Dependent Claims (2, 3, 4, 5)
-
-
6. The process of producing a silicate glass filter for ultraviolet light comprising ion exchange strengthening a silicate glass made by preparing a silicate glass making batch in which each 100 parts thereof by weight on an oxide basis consisting essentially of:
- about 64 to about 75 parts silicon dioxide, about 5 to about 10 parts potassium oxide, about 4 to about 8 parts sodium oxide, about 4 to about 8 parts calcium oxide, and about 2 to about 10 parts cerium oxide wherein said ion exchange is conducted at a temperature either above or below the strain point of said glass in a bath comprising salts of potassium and silver and whereby said glass provides an impact-resistant glass filter for ultraviolet light having a wavelength below 400 nanometers wherein said filter is transparent to light having a wavelength above 400 nanometers.
- View Dependent Claims (7, 8)
Specification