[. . . ] [. . . ] Thermal properties DOCTAN ® 2. 1 Viscosity and corresponding temperatures Description Viscosity log in dPas Temperature in °C 486 Strain point 14, 5 Annealing point 13, 0 537 Softening point 7, 6 723 Forming temperature 6, 0 790 Forming temperature 5, 0 884 Forming temperature 4, 0 1045 2. 2 Transformation temperature T g in °C Coefficient of thermal expansion 538 2. 3 2. 3. 1 Coefficient of mean linear thermal expansion (20°C ­ 300 °C) in 10-6 K-1 (static measurement) 9, 3 3 Specification Physical and chemical properties 3. Mechanical properties DOCTAN ® 3. 1 Density in g/cm3 Chemical properties 2, 52 4. 4. 1 Hydrolytic-resistance according to DIN ISO 719 Hydrolytic class HGB 3 Base-equivalent as Na2O per gram of glass grains in µg/g 156 4. 2 Acid-resistance according to DIN 12 116 Acid class Half reduction of surface weight after 6 hrs. in mg/dm2 S1 0, 4 4. 3 Base-resistance according to DIN ISO 695 Base class Reduction of surface weight after 3 hrs. in mg/dm2 A2 79 4 Annex Spectral transmittance Transmittance curve, DOCTAN 100 90 80 70 Transmittance in % 60 50 40 30 20 10 0 300 400 500 600 700 800 900 1000 1100 1200 1300 1400 1500 Wave length in nm 5 [. . . ] [. . . ]