Abstract: A lining material for glass melting furnaces comprises platinum or platinum alloy as a base material containing osmium as an impurity in an amount no more than 20 ppm. The lining material is used for that part of the melting furnace which comes into contact with molten glass. The low osmium content prevents the formation of bubbles in molten glass, thereby providing high-quality glass products.

Abstract: A lining material for glass melting furnaces comprises platinum or platinum alloy as a base material containing osmium as an impurity in an amount no more than 20 ppm. The lining material is used for that part of the melting furnace which comes into contact with molten glass. The low osmium content prevents the formation of bubbles in molten glass, thereby providing high-quality glass products.

Abstract: A lining material for glass melting furnaces comprises platinum or platinum alloy as a base material containing osmium as an impurity in an amount no more than 20 ppm. The lining material is used for that part of the melting furnace which comes into contact with molten glass. The low osmium content prevents the formation of bubbles in molten glass, thereby providing high-quality glass products.

Abstract: A lining material for glass melting furnaces comprises platinum or platinum alloy as a base material containing osmium as an impurity in an amount no more than 20 ppm. The lining material is used for that part of the melting furnace which comes into contact with molten glass. The low osmium content prevents the formation of bubbles in molten glass, thereby providing high-quality glass products.

Abstract: Ultraviolet and infrared radiation absorbing glass comprising, as basic glass components, 65 to 80% by weight of SiO.sub.2, 0 to 5% by weight of Al.sub.2 O.sub.3, 0 to 10% by weight of MgO, 5 to 15% by weight of CaO, 10 to 18% by weight of Na.sub.2 O, 0 to 5% by weight of K.sub.2 O, 5 to 15% by weight in total of MgO and CaO, 10 to 20% by weight in total of Na.sub.2 O and K.sub.2 O, and 0 to 5% by weight of B.sub.2 O.sub.3 ; and as coloring components, 0.75 to 0.95% by weight, in terms of Fe.sub.2 O.sub.3, of total iron oxide, 1.2 to 1.4% by weight of CeO.sub.2, and 0 to 0.5% by weight of TiO.sub.2, and satisfying equation (I):(0.2.times.(CeO.sub.2)-0.04).ltoreq.(FeO/T-Fe.sub.2 O.sub.3).ltoreq.(0.2.times.(CeO.sub.2)+0.08) (I)wherein (CeO.sub.2) represents the amount of CeO.sub.2 in terms of percent by weight, and (FeO/T-Fe.sub.2 O.sub.3) represents the weight ratio of FeO in terms of Fe.sub.2 O.sub.3 to the total iron oxide in terms of Fe.sub.2 O.sub.

Abstract: A glass melting furnace includes a furnace body including for storing molten glass, an upstanding tank including a bottom member lying flush with the bottom wall of the furnace body and a rear wall remote from the furnace body, the upstanding tank communicating with the furnace body, a feeder disposed upwardly of the rear wall of the upstanding tank and communicating with the upstanding tank, and a drainage mechanism disposed in a corner defined between the rear wall and bottom member of the upstanding tank for draining out heterogeneous molten glass. The upstanding tank has a width smaller than the width of the furnace body. The drainage mechanism comprises a through hole having an inlet opening into the upstanding tank and an outlet opening at a rear surface of the rear wall, the through hole being tapered from the inlet toward the outlet.

Abstract: An apparatus for producing a plate glass which comprises(A) a melter for storing a molten glass material,(B) a molding portion for molding the molten glass material from the melter into a plate,(C) a temperature adjusting tank located between the melter and the molding portion for maintaining the molten glass material from the melter at a uniform temperature, said temperature adjusting tank having a glass material channel for introducing the molten glass material maintained at the uniform temperature into the molding portion in a position facing on the molding portion, and(D) a tweel for adjusting a flow rate of the glass material which is raisable and lowerable in the glass material channel and has a hole through which a surface layer stream of the molten glass material can be separated and passed in the glass material channel.