Abstract: A phosphor layer for an electroluminescent panel comprises a phosphor powder held in a binder. The binder comprises a mixture of two constituents, one of which is a drying oil or a semi-drying oil or a derivative and the other constituent is a sol-gel precursors. Examples of suitable oils are linseed oil, grape seed oil, sunflower oil and soybean oil. Examples of suitable sol-gel precursors are tetraethyl orthosilicate, boron iso-propoxide, aluminium sec-butoxide titanium iso-propoxide. Metal salts such as metal alkoxides, metal acetates and metal nitrates may be mixed with the sol-gel precursors.

Abstract: A phosphor layer for an electroluminescent panel comprises a phosphor powder held in a binder. The binder comprises a mixture of two constituents, one of which is a drying oil or a semi-drying oil or a derivative and the other constituent is a sol-gel precursers. Examples of suitable oils are linseed oil, rape seed oil, sunflower oil and soyabean oil. Examples of suitable sol-gel precursers are tetraethyl orthosilicate, boron iso-propoxide, aluminium sec-butoxide and titanium iso-propoxide. Metal salts such as metal alkoxides, metal acetates and metal nitrates may be mixed with the sol-gel precursers.

Abstract: A phosphor layer for an electroluminescent panel comprises a phosphor powder held in a binder. The binder comprises a mixture of two constituents, one of which is a drying oil or a semi-drying oil or a derivative and the other constituent is a sol-gel precursers. Examples of suitable oils are linseed oil, rape seed oil, sunflower oil and soyabean oil. Examples of suitable sol-gel precursers are methyl orthosilicate, boron iso-propoxide, aluminium sec-butoxide and titanium iso-propoxide. Metal salts such as metal alkoxides, metal acetates and metal nitrates may be mixed with the sol-gel precursers.

Abstract: Sulphides are prepared by combining a dithionite compound with an aqueous alkaline solution of an appropriate cation or mixture of cations. On heating the corresponding sulphides are precipitated. The dithionite compound may be a dithionite dianion which is produced as an intermediary when thiourea dioxide is used as a starting material in the solution. Examples of appropriate cations are zinc (as zinc acetate) and copper (as copper acetate). The precipitate is dried and subsequently fired to produce high quality sulphides which may be used as phosphors or other optoelectronic materials.