Since its invention in the nineteenth century

the long afterglow phosphors have been improved greatly. Up to 1990s

the best product is metal sulfide long afterglow phosphors. The aluminates long afterglow luminescent material was invented at the beginning of the nineties

its luminescent brightness

long afterglow characteristics and stability were obviously superior to the above sulfide series products. However these phosphors still have bad anti-moisture character

and they have strict restriction over the raw material's purity and form

besides

the production cost was higher

therefore it also can not satisfy the requirement of usage very well. In 1998

silicate long afterglow phosphors are synthesized successfully

which having excellent chemistry stability. What is more

the development of red long afterglow phosphors also made great progress. The brightness of the best red phosphors is six times than that of CaS

the decay time is about 6～8 hours. Base on lots of literatures and experiments

the development

type

preparation and mechanism of the long afterglow phosphors are studied

and the properties of phosphors are compared with them in this paper.