UQG Optics

CORNING PYREX® 7740 BOROSILICATE
Chemical Composition
Pyrex® borosilicate glass has a very high resistance to attack from water, acids, salt solutions, halogens and organic solvents. It also has a moderate resistance to alkaline solutions. Only hydrofluoric acid, hot concentrated phosphoric acid and strong alkaline solutions cause appreciable corrosion of the glass.
Pyrex® glass has the following typical composition (percentage by weight):

SiO2 = 80.6%
B2O3 = 13.0%
Na2O = 4.0%
AI2O3 = 2.3%
Physical Properties
Coefficient of Expansion (20°C – 300°C) 3.3 x 10-6 K-1
Density 2.23 g/cm3
Refractive index (Sodium D line) 1.474
Dielectric Constant (1MHz,20°C) 4.6
Specific heat (20°C) 750J/kg°C
Thermal conductivity (20°C) 1.14W/m°C
Poisson's Ratio (25°C – 400°C) 0.2
Young's Modulus (25°C) 6400 kg/mm2
Optical Data


Pyrex® borosilicate glass has the ability to transmit light through the visible range of the spectrum and can be used effectively in the near ultra-violet range, making it ideally suitable for work in the field of photochemistry.

The graph above shows the degree of transmission of light as a function of wavelength in the ultra-violet, visible and infra-red sectors of the spectrum, for the thickness of glass generally encountered in laboratory ware (up to 5mm)
Refractive index (Sodium D line) = 1.474
Visible light transmission, 2mm thick glass = 92%
Visible light transmission, 5mm thick glass = 91%


WHILE EVERY ATTEMPT HAS BEEN MADE TO VERIFY THE SOURCE OF THE INFORMATION, NO RESPONSIBILITY IS ACCEPTED FOR ACCURACY OF DATA.