초록 ▼

A glass panel for a cathode ray tube including a substantially rectangular face portion and a skirt portion. Further constituting a side wall of the face portion, a compressive stress layer having a thickness of at least 1/10 of the thickness of the face portion, is formed on each of the inner and o

A glass panel for a cathode ray tube including a substantially rectangular face portion and a skirt portion. Further constituting a side wall of the face portion, a compressive stress layer having a thickness of at least 1/10 of the thickness of the face portion, is formed on each of the inner and outer surfaces of a useful screen area of the face portion, so as to satisfy 0.4≤σdi/σci≤1.0, where σciis the compressive stress on the inner surface at the center of the useful screen area, and σdiis the compressive stress on the inner surface in the vicinity of ends of diagonal axial lines of the useful screen area.

대표청구항 ▼

1. A glass panel for a cathode ray tube comprising: a substantially rectangular face portion having a radius of curvature which satisfies the equation: 0≤z≤r2/(1×104), where r is a distance (mm) on a diagonal axial line of the outer surface of the face portion of the useful screen area from

1. A glass panel for a cathode ray tube comprising: a substantially rectangular face portion having a radius of curvature which satisfies the equation: 0≤z≤r2/(1×104), where r is a distance (mm) on a diagonal axial line of the outer surface of the face portion of the useful screen area from a center axis to an end point of the useful screen area, and z is a distance (mm) from the end point to a tangential plane at the center of the useful screen area ; and a skirt portion forming a side wall of the face portion, wherein inner and outer surfaces of a useful screen area of the face portion include a compressive stress layer having a thickness of at least 1/10 of a thickness of the face portion, and which satisfies a compressive stress ratio: 0.4≤σdi/σci≤1.0, where σciis a compressive stress on the inner surface at a center of the useful screen area, and σdiis a compressive stress on the inner surface in a vicinity of ends of diagonal axial lines of the useful screen area. 2. The glass panel for a cathode ray tube according to claim 1, wherein the compressive stress σdiis within a range of 5.0≤|σdi|≤25.0 (MPa)... 3. The glass panel for a cathode ray tube according to claim 1, wherein the face portion has a radius of curvature which satisfies the equation: 0≤z≤r2/(1×104), where r is a distance (mm) on a diagonal axial line of the outer surface of the face portion of the useful screen area from a center axis to an end point of the useful screen area, and z is a distance (mm) from the end point to a tangential plane at the center of the useful screen area. 4. The glass panel for a cathode ray tube according to claim 1, wherein the compressive stress ratio satisfies the equation: 0.5≤σdi/σci≤0.8. 5. The glass panel for a cathode ray tube according to claim 2, wherein the compressive stress σdiis within a range of 6.0≤|σdi≤20.0 (MPa). 6. The glass panel for a cathode ray tube according to claim 3 1 , wherein the radius of curvature satisfies the equation: 0≤z≤r2/(6×104). 7. A glass panel for a cathode ray tube comprising: a substantially rectangular face portion; and a skirt portion forming a side wall of the face portion, wherein inner and outer surfaces of a useful screen area of the face portion include a compressive stress layer which satisfies a compressive stress ratio: 0.4≤σdi/σci≤1.0 0.5≤σdi/σci≤0.8 ,