GB402777A - Improved means for and methods of manufacturing, utilising and applying phosphorescent compounds - Google Patents

Abstract

Phosphorescent compositions are mixed with dehydrated sulphate of quinine to prevent decomposition of the phosphorescent ingredients. Dry zinc or calcium sulphide is mixed with sulphate of quinine which has been heated to remove water of crystallization to form a powder, or with the addition of glycerin and paraffinum liquidum to form a paste. A luminous paint is then prepared from the powder or paste by addition of a lacquer such as collodion or a mixture of French turpentine, copal or dammar, and boiled linseed oil. The powder may be first mixed with oleic acid and a small amount of ether to form a homogeneous paste. Small amounts of radio-active substances such as meso-thorium bromide, thorium sulpho-carbolate or oleate may be added, and powdered glass or pigments such as madder lake, barium chromate, chromium green, cobalt blue or cobalt arsenate. A mixture of powdered zinc and antimony may be incorporated to render the coating electrically conductive. Quinine sulphate may be replaced by a quinine compound formed by adding an alcoholic solution of iodine to a solution of quinine sulphate in acetic acid and dehydrating the crystals obtained. The paint may be applied to sheets of celluloid and a protecting coating of varnish then applied. Luminous sheets may be prepared by incorporating the phosphorescent powder with sufficient collodion and then rolling the resulting mixture. The compositions may be used as a backing for jewels, or in the manufacture of advertising and showcards, name plates and for rendering visible in the dark such articles as ash trays, table mats, watch faces and stands, medicine bottles, lock and keyhole surrounds, door knobs, stair mountings, corner indicators, meters, switches, and bell pushes.