FIRE PROTECTION DOUBLE-GLAZED GLASS

PROBLEM TO BE SOLVED: To improve the fire performance of a fire protection double-glazed glass by preventing a combustible gas from firing on the non-heated surface side even if the gas is generated from a primary sealing material in the glass during a fire, thereby blocking a flame.SOLUTION: In the double-glazed glass, at least two glass plates are placed opposite to each other through a spacer, lateral faces of the spacer opposite to the two glass plates are bonded respectively to the two glass plates with a primary sealing material to form a hollow layer between the two glass plates, and the outside of the primary sealing material is sealed with a secondary sealing material, wherein at least one heat-resistant, fire-retardant glass plate and at least one non-heat-resistant, fire-retardant glass plate are included to obtain a fire protection double-glazed glass. Edge parts of the non-heat-resistant, fire-retardant glass plate are subjected to an edge treatment to provide an objective fire protection double-glazed glass in which the edge strength of the non-heat-resistant, fire-retardant glass plate is increased to ≥50 MPa.