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Thermo-luminescent material

Assignee: Nemoto and Co Ltd
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Filing: 1977-06-24
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Granted: 1978-12-12
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Expires: 1997-06-24
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Abstract

Abstract A lithium fluoride thermo-luminescent material with increased sensitivity, which comprises crystals or powdery crystallites of lithium fluoride having present therein (A) luminescent center consisting of magnesium and at least one element or more selected from the elemental group consisting of copper, silver, and gold, and (B) sensitizer therefor consisting of at least one element or more selected from the elemental group consisting of carbon, phosphorus, sulfur, arsenic, selenium and tellurium.

Inventors

  • 👤 Takashi Matsuzawa

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 23:13
CPC Classifications
C; C09; C09K; C09K11/00; C09K11/08; C09K11/0827; C09K11/0833

Claims Analysis

Total Claims: 4
Claim 1
Independent Claim 91 words
A thermo-luminescent material which comprises crystals or powdery crystallites of lithium fluoride having present therein (A) activators consisting of from 0.05 to 1.0 mol% of magnesium in combination with at least one element selected from the elemental group consisting of copper, silver, and gold, in amount of 0.05-1.0 mol%, respectively, with respect to the LiF, and (B) sensitizers therefor consisting of at least one element selected from the group consisting of carbon, phosphorus, sulfur, arsenic, selenium and tellurium in amount of 0.1 - 5.0 mol% respectively with respect to the LiF.
Claim 2
Dependent Claim 91 words
A thermo-luminescent material which comprises crystals or powdery crystallites of lithium fluoride having present therein (A) activators consisting of from 0.05 to 1.0 mol% of magnesium in combination with at least one element selected from the elemental group consisting of copper, silver, and gold, in amount of 0.05-1.0 mol%, respectively, with respect to the LiF, and (B) sensitizers therefor consisting of at least one element selected from the group consisting of carbon, phosphorus, sulfur, arsenic, selenium and tellurium in amount of 0.1 - 5.0 mol% respectively with respect to the LiF.
Claim 3
Dependent Claim 133 words
A process for the preparation of a thermo-luminescent material, which process comprises adding to crystals or powdery crystallites of LiF (A) activators consisting of 0.05 - 1.0 mol% of magnesium and at least one element selected from the elemental group consisting of copper, silver, and gold, in amount of 0.05 - 1.0 mol%, respectively, with respect to the LiF, and (B) a sensitizer therefor consisting of at least one element selected from the elemental group consisting of carbon, phosphorus, sulfur, arsenic, selenium, and tellurium in amount of 0.1 - 5.0 mol%, respectively, with respect to the LiF to obtain a powdery mixture thereof; and heating said mixture at a temperature of from 700° to 1100° C. under an inert gas stream for a period of from about 30 minutes to about 3 hours.
Claim 4
Dependent Claim 133 words
A process for the preparation of a thermo-luminescent material, which process comprises adding to crystals or powdery crystallites of LiF (A) activators consisting of 0.05 - 1.0 mol% of magnesium and at least one element selected from the elemental group consisting of copper, silver, and gold, in amount of 0.05 - 1.0 mol%, respectively, with respect to the LiF, and (B) a sensitizer therefor consisting of at least one element selected from the elemental group consisting of carbon, phosphorus, sulfur, arsenic, selenium, and tellurium in amount of 0.1 - 5.0 mol%, respectively, with respect to the LiF to obtain a powdery mixture thereof; and heating said mixture at a temperature of from 700° to 1100° C. under an inert gas stream for a period of from about 30 minutes to about 3 hours.

References Cited (Backward Citations)

US3320180A Cited
US3413235A Cited
DE1221747B Cited
GB1154484A Cited
US3402293A Cited
PL53839Y1 Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-12-11 1982-06-12 1982-12-12 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-12-11 1986-06-12 1986-12-12 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-12-11 1990-06-12 1990-12-12 $7700.00 Window Closed / Lapsed

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