IMPROVEMENTS IN OR RELATING TO RADIO-ACTIVE SUBSTANCES

Patent · Wed Aug 10 04:00:00 EDT 1960

OSTI ID:4150635

Wilson, E J; Hughes, J D.H.

A method is presented for the manufacture of light sources by incorporating Kr/sup 85/ into a phosphor. A solution of quinol in 25% EtOH-75% H/ sub 2/O solvent is saturated with Kr/sup 85/-containing krypton and then cooled so that small crystals of the quinol-krypton clathrate compound separate. This powder is suitable for incorporation into phosphorescent materials by mixing it with a phosphor. e.g., activated ZnS, and adding to it a vehicle containing binder to form a paint or adding a powdered thermoplastic material to form a molding composition. Since the range of beta particles emitted by Kr/sup 85/ is approximately 1 mm in such materials, optimum brightness is reached with paint thickness > 1 mm; thicknesses of 2 to 3 mm are suitable. The clathrate- phosphor proportion is 1 to 10 for optimum brightness. Specific examples are given for the preparation of the clathrate and its incorporation. Light brightness data are given for 2- to 3-mm paint films consisting of the clathrate, polymethyl methacrylate binder, and quinol-saturated trichloroethylene vehicle at time intervals after fabrication from 5 to 500 days; it is seen that the brightness is very strong even after extensive darkening and remains 3x to 5x stronger than radium paints after 500 days. Variants of the method are discussed; Kr/sup 85/ might be replaced by tritiated H/sub 2/S, and the clathrate could be used as a radioactive source. (D.L.C.)

• Research Organization: Originating Research Org. not identified
• NSA Number: NSA-14-023176
• OSTI ID: 4150635
• Report Number(s): GB 843838
• Country of Publication: United Kingdom
• Language: English

Related Subjects

ACTIVATION
BINDERS
CHLORINATED HYDROCARBONS
COOLING
CRYSTALS
ETHYLENE
FABRICATION
HYDROGEN SULFIDES
INDUSTRIAL APPLICATIONS OF ISOTOPES AND RADIATIONS
KRYPTON 85
LIGHT
METHACRYLATES
METHANOL
METHYL RADICALS
MIXING
ORGANIC COMPOUNDS
PHOSPHORS
PIGMENTS
POLYMERS
POWDERS
SOLUTIONS
SOLVENTS
THICKNESS
TRITIUM
WATER
ZINC SULFIDES