Patent ID: 7088035
Filing Date: 2006-08-08
Classification: C03C,H01J

Abstract:
1. A glass bulb for a cathode ray tube comprising: a panel portion with a substantially rectangular face portion; and a funnel portion including a body portion with an opened end connected to the panel portion, wherein: glass constituting the funnel portion contains at least 60% of SiO the glass bulb, when assembled in a cathode ray tube, has a region which generates a tensile vacuum stress by the application of an atmospheric pressure to an outer surface of the glass bulb inside of which is vacuumed, and a compressive stress layer is formed partly by ion exchanging in an at least a region in the funnel portion, which includes a portion in an outer surface of the body portion of the funnel portion, in which σ the concentration of potassium ions is distributed according to a substantially step function in a thickness direction of the glass in the compressive stress layer, and when the maximum value of a compressive stress in the compressive stress layer is a σcm(MPa), the relation between σ