Patent ID: 6849996

Claim:
An electron emissive composition comprising: a barium tantalate composition of the formula (I) (Ba 1−x , Ca x , Sr p , D q ) 6 (Ta 1−y , W y , E t , F u , G v , Ca w ) 2 O (11±δ) (I) wherein δ is an amount of about 0 to about 6; and wherein D is either an alkali earth metal ion or an alkaline earth metal ion; E, F, and G are alkali earth metal ions, alkaline earth metal ions and/or transition metal ions; x is an amount of up to about 0.7; y is an amount of up to about 1; p and q are amounts of up to about 0.3; and t is an amount of about 0.05 to about 0.10; u is an amount of up to about 0.5; v is an amount of up to about 0.5 and w is an amount of up to about 0.25.