Patent ID: 11958937
Assignee: SK PUCORE CO., LTD.
Field: Macromolecular chemistry, polymers (Chemistry)
Classification: CPC C  G | IPC C  G

Claim 15:
16. The optical material of claim 12, which has a total light transmittance of 89% or more, and a change in yellow index (ΔY.I.) of greater than 0 to 1.5 as calculated according to the following Equation 1:

ΔY.I.={(234×x+106×y+106)/y}−{(234×xo+106×yo+106)/yo}  [Equation 1]

in Equation 1, xo and yo are chromaticity coordinates measured before a circular plate of the optical material having a thickness of 5 mm and a diameter of 75 mm is left in ultraviolet light, and x and y are chromaticity coordinates measured after the circular plate of the optical material is left in ultraviolet light for 24 hours.