K9 glass is a glass product made of K9 material, which is used in the field of optical coating, etc. K9 material belongs to optical glass, because it is crystal clear, so it has given rise to a lot of factories that process K9 material as the object, and the products they processed are called crystal glass products in the market.
K9 is composed as follows:
SiO2= 69.13% B2o3= 10.75% BaO = 3.07% Na2O=10.40% K2O=6.29% As2o3=0.36%
Its optical constants are: refractive index = 1.51630 dispersion = 0.00806 Abbe number = 64.06
The national standard for optical glass is classified according to the Abbe number, Abbe number ≥ 50 of the glass regulations for the coronet glass with "K" to indicate that the Abbe number < 50 of the glass regulations for the flint glass with "F" to indicate that the glass. Under these two categories, light "Q"; heavy "Z"; special "T" and chemical element symbols plus prefixes, numbers plus suffixes for subdivision, a total of 18 categories, 141 grades.
Example: BaK11 (barium corona) K9 (corona)
Generally speaking, Coronet belongs to the alkali silicate system and the vast majority of flint glass belongs to the lead silicate system.
K9 Glass