Abstract: A noble glass composition which is based on a known potassium-zinc crystal glass composition suitable for chemical strengthening, in which most of contained ZnO component is replaced with a combination of less expensive oxides. The noble glass composition is easily melted in a tank and formed by machine into table wares, and provides a chemical strengthened crystal glass article which has high practical strength as tableware and can be subjected to washing with an alkali.

Abstract: A speaker system provided with a globular glass enclosure to which a speaker unit is attached, wherein the enclosure is mounted elastically on a support member which consists of an elastic material and has an opening to accommodate a bottom part of the enclosure therein. The direction of the speaker unit can be freely changed under a stable posture and the occurrence of box noise due to the insufficient contact between the enclosure and the support member is prevented. In the speaker system, the enclosure may be fixed firmly at the position of its notch opening to a baffle board made of a highly rigid and/or highly oscillation-damping material for fixing the speaker unit to the baffle board, and thus the occurrence of box noise coming from the transmission of the vibration of the speaker unit to the enclosure and also coming from the deformation of the opening of the enclosure to receive the speaker unit can be prevented.

Abstract: In a laser beam glass cutting method, a glass article to be cut (for example a moulded tumbler having a moil) is maintained at a high temperature below the softening point of the glass and then the glass is repeatedly irradiated with a laser beam along the required cut-off line by rotating the glass. During this step, a tensile force is applied by gravity or by a mechanical device to the part to be cut off. Following removal of the part, the edge of the glass is irradiated again with the laser beam to effect fire-polishing thereof, so as to improve the shape of that edge. During the irradiation by the laser beam, an auxiliary inert gas is blown into the glass article to prevent glass deposition.