Phosphor, light-emitting device, and plasma display panel

1. A blue phosphor that is represented by a general formula xSrO.yEuO.MgO.zSiO 2 , where 2.970≦x≦3.500, 0.006≦y≦0.030, and 1.900≦z≦2.100,

wherein the blue phosphor has a crystal structure that is essentially a merwinite structure, and

the crystal structure has a unit cell volume of 714.8 Å 3 or less.

2. The blue phosphor according to claim 1 ,

wherein an a-axis length is 13.871 Å or less.

3. The blue phosphor according to claim 1 ,

wherein a b-axis length is 5.455 Å or less.

4. The blue phosphor according to claim 1 ,

wherein a c-axis length is 9.447 Å or less.

5. The blue phosphor according to claim 1 ,

wherein an angle β between the a-axis and the c-axis is 90.180 degrees or less.

6. The blue phosphor according to claim 1 ,

wherein the blue phosphor has an impurity crystalline phase at least partially, and

the impurity crystalline phase has an akermanite structure.

7. The blue phosphor according to claim 6 ,

wherein the abundance ratio of the impurity crystalline phase having the akermanite structure is 1.96% or less.

8. A blue phosphor that is represented by a general formula xSrO.yEuO.MgO.zSiO 2 , where 2.97≦x≦3.500, 0.006≦y≦0.030, and 1.900≦z≦2.100,

wherein a peak has a one-fifth value width of 0.17 degrees or less, the peak appearing around 2θ=22.86 degrees in an X-ray diffraction pattern obtained by measurement of the blue phosphor using an X-ray with a wavelength of 0.773 Å.

9. The blue phosphor according to claim 1 ,

wherein in the general formula, 2.982≦x≦2.994, 0.006≦y≦0.018, and 1.995≦z≦2.005 are satisfied.

10. A light-emitting device, comprising a phosphor layer including the phosphor according to claim 1 .

11. The light-emitting device according to claim 10 ,

wherein the light-emitting device is a plasma display panel.

12. The light-emitting device according to claim 11 ,

wherein the plasma display panel comprises:

a front panel;

a back panel that is arranged to face the front panel;

barrier ribs that define the clearance between the front panel and the back panel;

a pair of electrodes that are disposed on the back panel or the front panel;

an external circuit that is connected to the electrodes;

a discharge gas that is present at least between the electrodes and contains xenon that generates a vacuum ultraviolet ray by applying a voltage between the electrodes through the external circuit; and

phosphor layers that emit visible light induced by the vacuum ultraviolet ray,

the phosphor layers include a blue phosphor layer, and

the blue phosphor layer contains the phosphor.

13. The blue phosphor according to claim 1 ,

wherein the blue phosphor is obtained by firing a mixed powder of source materials at 1200 to 1400° C. under a partial pressure of oxygen of 1×10 −9 to 1×10 −5 Pa.

14. The blue phosphor according to claim 8 ,

wherein the blue phosphor is obtained by firing a mixed powder of source materials at 1200 to 1400° C. under a partial pressure of oxygen of 1×10 −9 to 1×10 −5 Pa.

15. The blue phosphor according to claim 8 ,

wherein in the general formula, 2.982≦x≦2.994, 0.006≦y≦0.018, and 1.995≦z≦2.005 are satisfied.

16. A light-emitting device, comprising a phosphor layer including the phosphor according to claim 8 .

17. The light-emitting device according to claim 16 ,

wherein the light-emitting device is a plasma display panel.

18. The light-emitting device according to claim 17 ,

wherein the plasma display panel comprises:

a front panel;

a back panel that is arranged to face the front panel;

barrier ribs that define the clearance between the front panel and the back panel;

a pair of electrodes that are disposed on the back panel or the front panel;

an external circuit that is connected to the electrodes;

a discharge gas that is present at least between the electrodes and contains xenon that generates a vacuum ultraviolet ray by applying a voltage between the electrodes through the external circuit; and

phosphor layers that emit visible light induced by the vacuum ultraviolet ray,

the phosphor layers include a blue phosphor layer, and

the blue phosphor layer contains the phosphor.