Claims
- 1. A long persistence red emitting phosphor comprising a trivalent or quadrivalent ion that acts as a thermal trap in a phosphor comprising a doubly activated alkaline earth phosphate, an alkaline earth magnesium silicate or an alkaline earth magnesium di-silicate activated with europium and manganese.
- 2. A phosphor according to claim 1 wherein said trivalent ion is dysprosium.
- 3. A phosphor according to claim 1 wherein said trivalent ion is neodymium.
- 4. A phosphor according to claim 1 wherein said quadrivalent ion is titanium.
- 5. A phosphor according to claim 1 wherein said quadrivalent ion is zirconium.
- 6. A phosphor according to claim 1 wherein said phosphor is selected from the group consisting of Sr.sub.2 P.sub.2 O.sub.7 ;Eu:Mn:Dy; Ba.sub.3 MgSi.sub.2 O.sub.8 :Eu:Mn:Dy; (Ba,Sr,Ca).sub.3 MgSi.sub.2 O.sub.8 :Eu:Mn:Nd and (Sr,Ba)MgSiO.sub.4 :Eu:Mn:Dy.
- 7. A red emitting long persistence phosphor comprising Sr.sub.2.86 Eu.sub.0.04 Mn.sub.0.10 MgSi.sub.2 O.sub.8 activated with a trivalent cation or a quadrivalent cation.
Parent Case Info
This application claims the benefit of Provisional application Ser. No. 60/079,958 filed Mar. 31, 1998.
US Referenced Citations (4)
Non-Patent Literature Citations (1)
Entry |
Chemical Abstract citation 80:102,210; abstract for Japanese B4 patent JP48034115, published Oct. 18, 1973. |