METHOD OF PREPARING OF STRUCTURAL OPTICS MULTILAYER ARTICLE Russian patent published in 1995 - IPC

FIELD: optical articles. SUBSTANCE: multilayer article of structural optics consists of the external and internal silicate plates and rear organic plate. Glass and technological plates are subjected for preliminary sagging, then glass plates are hardened in potassium nitrate melt at 430-500 C for 20-120 h. Hardened glass plates are glued each with other with polyvinylbutyral films with thin rear organic plate and technological one. Strength of glass edge is 29 kg/mm², annealing stresses are 25-75 mmc/cm. Method is used for making of shock-resistant articles. EFFECT: enhanced quality of articles made. 1 tbl