Laminated glass and its production process

A laminated glass comprising a plurality of glass plates bent into a predetermined shape, and an interlayer interposed between the plurality of glass plates, at least two glass plates among the plurality of glass plates being a thick glass plate and a thin glass plate differing in the plate thickness;

• wherein at any temperature between the annealing point and the softening point of the thick glass plate, the thick glass plate between the two glass plates differing in the plate thickness, has a lower viscosity than the thin glass plate, and
• wherein the two glass plates differing in the plate thickness satisfy the formula 1<y<(1.22−0.206×x) and the formula 1<z<(1.15−0.131×x),
• wherein x (x=t2/t1) is the ratio of the plate thickness (t2) of the thin glass plate to the plate thickness (t1) of the thick glass plate at room temperature;
• y (y=log10 η2/log10η1) is the ratio of the logarithm (log10 η2) of the viscosity of the thin mass plate to the logarithm (log10 η1) of the viscosity of the thick glass plate, at the annealing point of the thick glass plate;
• and
• z (z=log10 η4/log10 η3) is the ratio of the logarithm (log10 η4) of the viscosity of the thin glass plate to the logarithm (log10 η3) of the viscosity of the thick glass plate, at the softening point of the thick glass plate.