Improvements in or relating to electroluminescent elements

摘要

An electroluminescent element, Fig. 1, comprises a metal carrier 1 consisting of nickel-iron alloy having a composition by weight of from 50 to 80% of nickel and from 50 to 20% of iron, a glass-enamel layer 2 in which the electro-luminescent material is embedded, a conductive transparent layer 3 of tin oxide and a glass protective layer 4. The glass-enamel is of low acidity and has the mol. per cent composition: Na2O-17.5, K2O-5, CaO-5.5, SrO-3, BaO-3, ZnO-7, SiO2-10.5, B2O3-37.5, Al2O3-11. The electroluminescent material can be ZnS activated by Cu, Ag, Au or Mn and co-activated by Al or Cl. In the construction shown in Fig. 2, a composite glass-enamel layer is formed of two layers 13 and 14, the layer 13 containing TiO2 pigment and the layer 14 containing the ZnS. The Ni-Fe alloy carrier 11 can have a thickness of 0.2 mm., and a composition by weight of 75% Ni and 25% Fe, i.e. "Mu-metal" (Registered Trade Mark). The layer 13 can have a thickness of 5-50m with a volume content of TiO2 pigment of 5-20%, and the layer 14 can have a thickness of 15-50m with a volume content of activated ZnS of 20-50%.ALSO: An electroluminescent element, Fig. 1, comprises a metal carrier 1 consisting of Ni-Fe alloy having a composition by weight of from 50-80% Ni and from 50-20% Fe, a glass-enamel layer 2 in which the electroluminescent material is embedded, a conductive transparent layer 3 of tin oxide and a glass protective layer 4. The glass-enamel is of low acidity and has the mol. per cent composition : Na2O-17.5, K2O-5, CaO-5.5, SrO-3, BaO-3, ZnO-7, SiO2-10.5, B2O3-37.5, Al2O3-11. The electroluminescent material can be ZnS activated by Cu, Ag, Au or Mn and co-activated by Al or Cl. In the construction shown in Fig. 2 a composite glass-enamel layer is formed of two layers 13 and 14, the layer 13 containing TiO2 pigment and the layer 14 containing the ZnS. The Ni-Fe alloy carrier 11 can have a thickness of 0.2 mm. and a composition by weight of 75% Ni and 25% Fe, i.e. " Mu-metal " (Registered Trade Mark). The layer 13 can have a thickness of 5-50 m , preferably 15m , with a volume content of TiO2 pigment of 5-20%, preferably 10%, and the layer 14 can have a thickness of 15-50m , preferably 25m , with a volume content of activated ZnS of 20-50%, preferably 30%.ALSO:A Ni-Fe alloy carrier plate which can form an electrode in an electroluminescent device has the weight composition: Ni 50 to 80%, Fe 50 to 20%, preferably Ni 75%, Fe 25%, i.e. "Mumetal" (Registered Trade Mark).