METHOD OF CUTTING DOWN NUMBER OF BUBBLES IN GLASS PRODUCT (VARIANTS) AND GLASS PRODUCT Russian patent published in 2002 - IPC

FIELD: glassmaking industry. SUBSTANCE: optical fiber semiproduct from sintered dense glass having aluminium oxide is extended and then heated to temperature between 1490 and 1495 to remove bubbles when no crystallization occurs. Extended glass product is thereafter either directly extended to form optical fiber or coating is applied onto product which is then extended to form fiber. Glass product with aluminium oxide additive has first maximum of aluminium oxide concentration of about 1.3 wt % in core and second maximum of about 2.35 wt % at radical distance. EFFECT: lower content of bubbles in semiproducts for extending optical fiber and less possibility of crystallizing semiproducts thus making it possible to prepare long length fibers. 11 cl, 10 dwg, 2 tbl