Barium is not an extensively used element. Most is used in drilling fluids for oil and gas wells (Barium compound-containing thickening agent and drilling fluids made therefrom (1986)).
It is also used in paint (Water dispersion paint containing barium compound to prevent blooming (1955)), and in glassmaking (Process for the manufacture of glass containing barium (1928)).
Barium oxide has been incorporated into the screens of cathode ray television tubes to minimise the forward emission of X-rays (CRT panel glass high in x-ray absorbability and low in devitrification (2003)).
A suspension of barium sulfate is sometimes given to patients suffering from digestive disorders. This is a ‘barium meal’ or ‘barium enema’. Barium is a heavy element and scatters X-rays, so as it passes through the body, the stomach and intestines can be distinguished on an X-ray (Barium sulfate contrast medium for X-ray examination of the large intestine (1990)).
Barium carbonate has been used in the past as a rat poison (Method for continuously providing aqueous barium carbonate solution of to-be-mixed substances, for use in e.g. rat poison, involves passing subsets of substances into hermetically sealed mixing vessel and performing mixing process in vessel (2013)).
Barium nitrate is used in pyrotechnics (Pyrotechnic mixture comprises red phosphorus, magnesium, barium nitrate and polyvinyl chloride, for munition (2007)), and fireworks (Firework on metal stem with kindling head – consists of barium nitrate, aluminium powder, iron powder, shellac and binder (1975)).
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All patent information has been obtained from Espacenet (European Patent Office).