Claims
- 1. A storage phosphor consisting essentially of the product of firing, at a temperature from about 700.degree. to 1300.degree. C., a combination of species characterized by the relationship:
- MFX.sub.1-z I.sub.z.uM.sup.a X.sup.a :yA:eQ:tD
- wherein
- M is selected from the group consisting of Mg, Ca, Sr, and Ba and combinations thereof;
- X is selected from the group consisting of Cl and Br and combinations thereof;
- Ma is selected from the group consisting of Na, K, Rb, and Cs and combinations thereof;
- Xa is selected from the group consisting of F, Cl, Br, and I and combinations thereof;
- A is selected from the group consisting of Eu, Ce, Sm, and Tb and combinations thereof;
- Q is selected from the group consisting of BeO, MgO, CaO, SrO, BaO, ZnO, Al.sub.2 O.sub.3, La.sub.2 O.sub.3, In.sub.2 O.sub.3, SiO.sub.2, TiO.sub.2, ZrO.sub.2, GeO.sub.2, SnO.sub.2, Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, and ThO.sub.2 and combinations thereof;
- D is selected from the group consisting of V, Cr, Mn, Fe, Co, and Ni and combinations thereof;
- z is from 1.times.10.sup.-4 to 1;
- u is from 0 to 1;
- y is from 1.times.10.sup.-4 to 0.1;
- e is from 0 to 1; and
- t is from 0 to 1.times.10.sup.-2 ; and oxosulfur reducing agent for iodine,
- wherein said oxosulfur reducing agent for iodine is present with said combination of species in an amount sufficient to increase relative photostimulated luminescence intensities relative to the phosphor defined above absent said reducing agent for iodine.
- 2. The storage phosphor of claim 1 wherein said oxosulfur reducing agent is selected from the group consisting of oxosulfur species having the general formula S.sub.j O.sub.k wherein 0.25<j/k<1.0.
- 3. The storage phosphor of claim 1 wherein said reducing agent is selected from the group consisting of: inorganic and organic salts of SO.sub.3.sup.2-, S.sub.2 O.sub.4.sup.2-, S.sub.2 O.sub.3.sup.2-, S.sub.2 O.sub.5.sup.2-, and S.sub.4 O.sub.6.sup.2- and Bunte salts and combinations thereof.
- 4. The storage phosphor of claim 1 wherein said reducing agent comprises thiosulfate salt.
- 5. The storage phosphor of claim 1 wherein t=0.
- 6. The storage phosphor of claim 1 further characterized as the product of firing a composition of matter consisting essentially of oxosulfur reducing agent for iodine, and a combination of species characterized by the relationship:
- (Ba.sub.1-a-b-c Mg.sub.a Ca.sub.b Sr.sub.c)FX.sub.1-z I.sub.z.rM.sup.a X.sup.a :YA:eQ
- wherein
- X is selected from the group consisting of Cl and Br and combinations thereof;
- M.sup.a is selected from the group consisting of Na, K, Rb, and Cs and combinations thereof;
- X.sup.a is selected from the group consisting of F, Cl, Br, and I and combinations thereof;
- A is selected from the group consisting of Eu, Ce, Sm, and Tb and combinations thereof;
- Q is selected from the group consisting of BeO, MgO, CaO, SrO, BaO, ZnO, Al.sub.2 O.sub.3, La.sub.2 O.sub.3, In.sub.2 O.sub.3, SiO.sub.2, TiO.sub.2, ZrO.sub.2, GeO.sub.2, SnO.sub.2, Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, and ThO.sub.2 and combinations thereof;
- a+b+c is from 0 to 0.4;
- z is from 1.times.10.sup.-4 to 1;
- r is from 1.times.10.sup.-6 to 0.1;
- y is from 1.times.10.sup.-4 to 0.1;
- e is from 1.times.10.sup.-5 to 0.1; and
- wherein said oxosulfur reducing agent for iodine is present with said combination of species in an amount sufficient to increase relative photostimulated luminescence intensities relative to the phosphor defined above absent said oxosulfur reducing agent.
- 7. The storage phosphor of claim 6 wherein said reducing agent is selected from the group consisting of the group consisting of oxosulfur species having the general formula S.sub.j O.sub.k wherein 0.25<j/k1.0.
- 8. The storage phosphor of claim 6 wherein said reducing agent is selected from the group consisting of: salts of SO.sub.3.sup.2-, S.sub.2 O.sub.4.sup.2-, S.sub.2 O.sub.3.sup.2-, S.sub.2 O.sub.5.sup.2-, and S.sub.4 O.sub.6.sup.2- and Bunte salts and combinations thereof.
- 9. The storage phosphor of claim 6 wherein said reducing agent comprises thiosulfate salt.
- 10. The storage phosphor of claim 6 wherein said reducing agent is present in said phosphor in a molar ratio of sulfur to alkaline earth metal of less than 0.020.
- 11. The storage phosphor of claim 1 wherein said reducing agent is present in said phosphor in a molar ratio of sulfur to alkaline earth metal of less than 0.020.
- 12. The storage phosphor of claim 1 wherein said reducing agent is present in said composition of matter in a molar ratio of sulfur to alkaline earth metal of from 1.times.10.sup.-4 to 0.020.
- 13. A storage phosphor comprising the product of firing, at a temperature from about 700.degree. to 1300.degree. C., a composition of matter consisting essentially of oxosulfur reducing agent for iodine, and a combination of species characterized by the relationship:
- (Ba.sub.1-a-b-c Mg.sub.a Ca.sub.b Sr.sub.c)FX.sub.1-z I.sub.z.rM.sup.a X.sup.a :yA:eQ
- wherein
- X is selected from the group consisting of Cl and Br and combinations thereof;
- M.sup.a is selected from the group consisting of Na, K, Rb, and Cs and combinations thereof;
- X.sup.a is selected from the group consisting of F, Cl, Br, and I and combinations thereof;
- A is selected from the group consisting of Eu, Ce, Sm, and Tb and combinations thereof;
- Q is selected from the group consisting of BeO, MgO, CaO, SrO, BaO, ZnO, Al.sub.2 O.sub.3, La.sub.2 O.sub.3, In.sub.2 O.sub.3, SiO.sub.2, TiO.sub.2, ZrO.sub.2, GeO.sub.2, SnO.sub.2, Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, and ThO.sub.2 and combinations thereof;
- a+b+c is from 0 to 0.4;
- z is from 1.times.10.sup.-4 to 1;
- r is from 1.times.10.sup.-6 to 0.1;
- y is from 1.times.10.sup.-4 to 0.1;
- e is from 1.times.10.sup.-5 to 0.1; and
- wherein said oxosulfur reducing agent is selected from the group consisting of Bunte compounds having the general formula R'SSO.sub.3 D, where R' is a covalently bonded organic substituent and D is a counterion, and organic and inorganic oxosulfur salts having anions of the general formula S.sub.j O.sub.k wherein 0.25<j/k<1.0;
- and wherein said oxosulfur reducing agent is present prior to said firing in a molar ratio of sulfur to alkaline earth metal of greater than 1.times.10.sup.-4 and less than 0.020.
- 14. The phosphor of claim 13 wherein A is Eu.
- 15. The phosphor of claim 13 wherein said reducing agent is selected from the group consisting of: salts of SO.sub.3.sup.2-, S.sub.2 O.sub.4.sup.2-, S.sub.2 O.sub.3.sup.2-, S.sub.2 O.sub.5.sup.2-, and S.sub.4 O.sub.6.sup.2-.
- 16. The phosphor of claim 13 wherein said oxosulfur reducing agent comprises thiosulfate.
- 17. A radiographic image storage panel comprising a support and a fluorescent layer including phosphor crystals capable of absorbing X-radiation and emitting longer wavelength electromagnetic radiation in response to stimulating radiation of a third wavelength, said phosphor crystals consisting essentially of the product of firing, at a temperature from about 700.degree. to 1300.degree. C., a combination of species characterized by the relationship:
- MFX.sub.1-z I.sub.z.uM.sup.a X.sup.a :yA:eQ:tD
- wherein
- M is selected from the group consisting of Mg, Ca, Sr, and Ba and combinations thereof;
- X is selected from the group consisting of Cl and Br and combinations thereof;
- M.sup.a is selected from the group consisting of Na, K, Rb, and Cs and combinations thereof;
- X.sup.a is selected from the group consisting of F, Cl, Br, and I and combinations thereof;
- A is selected from the group consisting of Eu, Ce, Sm, and Tb and combinations thereof;
- Q is selected from the group consisting of BeO, MgO, CaO, SrO, BaO, ZnO, Al.sub.2 O.sub.3, La.sub.2 O.sub.3, In.sub.2 O.sub.3, SiO.sub.2, TiO.sub.2, ZrO.sub.2, GeO.sub.2, SnO.sub.2, Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, and ThO.sub.2 and combinations thereof;
- D is selected from the group consisting of V, Cr, Mn, Fe, Co, and Ni and combinations thereof;
- z is from 1.times.10.sup.-4 to 1;
- u is from 0 to 1;
- y is from 1.times.1.times.10.sup.-4 to 0.1;
- e is from 0 to 1; and
- t is from 0 to 1.times.10.sup.-2 ; and oxosulfur reducing agent for iodine,
- wherein said oxosulfur reducing agent for iodine is present in said combination of species in an amount sufficient to increase relative photostimulated luminescence intensities relative to the phosphor defined above absent said reducing agent for iodine.
- 18. The panel of claim 17 further characterized as consisting essentially of the product of firing a composition of matter consisting essentially of oxosulfur reducing agent for iodine, and a combination of species characterized by the relationship:
- (Ba.sub.1-a-b-c Mg.sub.a Ca.sub.b Sr.sub.c)FX.sub.1-z I.sub.z.rM.sup.a X.sup.a :yA:eQ
- wherein
- X is selected from the group consisting of Cl and Br;
- M.sup.a is selected from the group consisting of Na, K, Rb, and Cs;
- X.sup.a is selected from the group consisting of F, Cl, Br, and I;
- A is selected from the group consisting of Eu, Ce, Sm, and Tb;
- Q is selected from the group consisting of BeO, MgO, CaO, SrO, BaO, ZnO, Al.sub.2 O.sub.3, La.sub.2 O.sub.3, In.sub.2 O.sub.3, SiO.sub.2, TiO.sub.2, ZrO.sub.2, GeO.sub.2, SnO.sub.2, Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, and ThO.sub.2 ;
- a+b+c is from 0 to 0.4;
- z is from 1.times.10.sup.-4 to 1;
- r is from 10.sup.-6 to 0.1;
- y is from 1.times.10.sup.-4 to 0.1;
- e is from 10.sup.-5 to 0.1; and
- wherein said oxosulfur reducing agent for iodine is present prior to said firing in an amount sufficient to increase relative photostimulated luminescence intensities relative to the phosphor defined above absent said oxosulfur reducing agent.
- 19. The panel of claim 18 wherein said oxosulfur reducing agent is present prior to said firing, in a molar ratio of sulfur to alkaline earth metal of greater than 1.times.10.sup.-4 and less than 0.020.
- 20. The panel of claim 19 wherein said oxosulfur reducing agent is selected from the group consisting of Bunte compounds having the general formula R'SSO.sub.3 D, where R' is a covalently bonded organic substituent and D is a counterion, and organic and inorganic oxosulfur salts having anions of the general formula S.sub.j O.sub.k wherein 0.25<j/k<1.0.
- 21. The panel of claim 19 wherein said reducing agent is selected from the group consisting of: salts of SO.sub.3.sup.2-, S.sub.2 O.sub.4.sup.2-, S.sub.2 O.sub.3.sup.2-, S.sub.2 O.sub.5.sup.2-, and S.sub.4 O.sub.6.sup.2-.
- 22. A method for preparing a radiographic storage phosphor comprising
- dispersing in an aqueous solvent an oxosulfate reducing agent for molecular iodine and a plurality of precursor compounds having the total elemental composition of a phosphor selected from the group consisting of divalent alkaline earth metal fluorohalide phosphors containing iodine which satisfy the relationship:
- MFX.sub.1-z I.sub.z.uM.sup.a X.sup.a :yA:eQ:tD
- wherein
- M is selected from the group consisting of Mg, Ca, Sr, and Ba and combinations thereof;
- X is selected from the group consisting of Cl and Br and combinations thereof;
- M.sup.a is selected from the group consisting of Na, K, Rb, and Cs and combinations thereof;
- X.sup.a is selected from the group consisting of F, Cl, Br, and I and combinations thereof;
- A is selected from the group consisting of Eu, Ce, Sm, and Tb and combinations thereof;
- Q is selected from the group consisting of BeO, MgO, CaO, SrO, BaO, ZnO, Al.sub.2 O.sub.3, La.sub.2 O.sub.3, In.sub.2 O.sub.3, SiO.sub.2, TiO.sub.2, ZrO.sub.2, GeO.sub.2, SnO.sub.2, Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, and ThO.sub.2 and combinations thereof;
- D is selected from the group consisting of V, Cr, Mn, Fe, Co, and Ni and combinations thereof;
- z is from 1.times.10.sup.-4 to 1;
- u is from 0 to 1;
- y is from 1.times.10.sup.-4 to 0.1;
- e is from 0 to 1; and
- t is from 0 to 1.times.10.sup.-2 ;
- wherein said oxosulfur reducing agent for iodine is present with said precursor compounds in a molar ratio of sulfur to alkaline earth metal of greater than 1.times.10.sup.-4 and less than 0.020; said plurality of precursor compounds yielding said phosphor as a product of firing;
- drying said dispersion; and
- firing the product of said drying, said firing being at a temperature from about 700.degree. to 1300.degree. C.
- 23. The method of claim 22 wherein said precursor compounds satisfy the relationship:
- (Ba.sub.1-a-b-c Mg.sub.a Ca.sub.b Sr.sub.c)FX.sub.1-z I.sub.z.rM.sup.a X.sup.a :yA:eQ
- wherein
- X is selected from the group consisting of Cl and Br and combinations thereof;
- M.sup.a is selected from the group consisting of Na, K, Rb, and Cs and combinations thereof;
- X.sup.a is selected from the group consisting of F, Cl, Br, and I and combinations thereof;
- A is selected from the group consisting of Eu, Ce, Sm, and Tb and combinations thereof;
- Q is selected from the group consisting of BeO, MgO, CaO, SrO, BaO, ZnO, Al.sub.2 O.sub.3, La.sub.2 O.sub.3, In.sub.2 O.sub.3, SiO.sub.2, TiO.sub.2, ZrO.sub.2, GeO.sub.2, SnO.sub.2, Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, and ThO.sub.2 and combinations thereof;
- a+b+c is from 0 to 0.4;
- z is from 1.times.10.sup.-4 to 1;
- r is from 1.times.10.sup.-6 to 0.1;
- y is from 1.times.10.sup.-4 to 0.1;
- e is from 1.times.10.sup.-5 to 0.1.
- 24. A method for preparing a stabilized radiographic phosphor intermediate comprising dispersing in an aqueous solvent an oxosulfate reducing agent and a plurality of precursor compounds having the total elemental composition of a phosphor selected from the group consisting of divalent alkaline earth metal fluorohalide phosphors containing iodine which satisfy the relationship:
- MFX.sub.1-z I.sub.z.uM.sup.a X.sup.a :yA:eQ:tD
- wherein
- M is selected from the group consisting of Mg, Ca, Sr, and Ba and combinations thereof;
- X is selected from the group consisting of Cl and Br and combinations thereof;
- M.sup.a is selected from the group consisting of Na, K, Rb, and Cs and combinations thereof;
- X.sup.a is selected from the group consisting of F, Cl, Br, and I and combinations thereof;
- A is selected from the group consisting of Eu, Ce, Sm, and Tb and combinations thereof;
- Q is selected from the group consisting of BeO, MgO, CaO, SrO, BaO, ZnO, Al.sub.2 O.sub.3, La.sub.2 O.sub.3, In.sub.2 O.sub.3, SiO.sub.2, TiO.sub.2, ZrO.sub.2, GeO.sub.2, SnO.sub.2, Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, and ThO.sub.2 and combinations thereof;
- D is selected from the group consisting of V, Cr, Mn, Fe, Co, and Ni and combinations thereof;
- z is from 1.times.10.sup.-4 to 1;
- u is from 0 to 1;
- y is from 1.times.10.sup.-4 to 0.1;
- c is from 0 to 1; and
- t is from 0 to 1.times.10.sup.-2 ;
- wherein said oxosulfur reducing agent for iodine is present with said precursor compounds in a molar ratio of sulfur to alkaline earth metal of greater than 1.times.10.sup.-4 and less than 0.020.
- 25. The method of claim 24 further comprising drying said dispersion using microwave radiation.
- 26. The method of claim 25 wherein said reducing agent is selected from the group consisting of Bunte compounds having the general formula R'SSO.sub.3 D, where R' is a covalently bonded organic substituent and D is a counterion, and organic and inorganic oxosulfur salts having anions of the general formula S.sub.j O.sub.k wherein 0.25<j/k<1.0.
- 27. A stabilized radiographic phosphor intermediate comprising an oxosulfate reducing agent and a plurality of precursor compounds having the total elemental composition of a phosphor selected from the group consisting of divalent alkaline earth metal fluorohalide phosphors containing iodine which satisfy the relationship:
- MFX.sub.1-z I.sub.z.uM.sup.a X.sup.a :yA:eQ:tD
- wherein
- M is selected from the group consisting of Mg, Ca, Sr, and Ba and combinations thereof;
- X is selected from the group consisting of Cl and Br and combinations thereof;
- M.sup.a is selected from the group consisting of Na, K, Rb, and Cs and combinations thereof;
- X.sup.a is selected from the group consisting of F, Cl, Br, and I and combinations thereof;
- A is selected from the group consisting of Eu, Ce, Sm, and Tb and combinations thereof;
- Q is selected from the group consisting of BeO, MgO, CaO, SrO, BaO, ZnO, Al.sub.2 O.sub.3, La.sub.2 O.sub.3, In.sub.2 O.sub.3, SiO.sub.2, TiO.sub.2, ZrO.sub.2, GeO.sub.2, SnO.sub.2, Nb.sub.2 O.sub.5, Ta.sub.2 O.sub.5, and ThO.sub.2 and combinations thereof;
- D is selected from the group consisting of V, Cr, Mn, Fe, Co, and Ni and combinations thereof;
- z is from 1.times.10.sup.-4 to 1;
- u is from 0 to 1;
- y is from 1.times.10.sup.-4 to 0.1;
- e is from 0 to 1; and
- t is from 0 to 1.times.10.sup.-2 ;
- wherein said oxosulfur reducing agent for iodine is present with said precursor compounds in a molar ratio of sulfur to alkaline earth metal of greater than 1.times.10.sup.-4 and less than 0.020.
- 28. The stabilized radiographic phosphor intermediate of claim 27 wherein said oxosulfur reducing agent is selected from the group consisting of Bunte compounds having the general formula R'SSO.sub.3 D, where R' is a covalently bonded organic substituent and D is a counterion, and organic and inorganic oxosulfur salts having anions of the general formula S.sub.j O.sub.k wherein 0.25<j/k<1.0.
- 29. The phosphor of claim 1 wherein M is
- Ba.sub.(1-a) Sr.sub.(a)
- wherein a is from 5.times.10.sup.-6 to 0.015.
- 30. The method of claim 22 wherein M is
- Ba.sub.(1-a) Sr.sub.(a)
- wherein a is from 5.times.10.sup.-6 to 0.015.
Parent Case Info
This is a Continuation-In-Part of patent application Ser. No. 08/157,582, filed Nov. 24, 1993, now abandoned.
US Referenced Citations (18)
Foreign Referenced Citations (2)
Number |
Date |
Country |
0234385 |
Sep 1987 |
EPX |
2017140 |
Oct 1979 |
GBX |
Non-Patent Literature Citations (3)
Entry |
Research Disclosure, vol. 154, Feb. 1977, Item 15444. |
Research Disclosure, vol. 176, Dec. 1978, Item 17643, Section XVII. |
Research Disclosure, vol. 184, Aug. 1979, Item 18431, Section I. |
Continuation in Parts (1)
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Number |
Date |
Country |
Parent |
157582 |
Nov 1993 |
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