U.S. Philips Corporation

U.S. Phillips Corporation

Ulrich H Kynast

Volker U Weiler

Cornelis Reinder Ronda

Markus Haase

Michael Bredol

Herbert Friedrich Boerner

Wolfgang Busselt

Helmut Bechtel

Wolfram Czarnojan

Stefan Gruhlke

Herbert Friedrich Borner

Guido Hutten

Thomas Rink

An organic electroluminescent component with a layer arrangement includes a first electrode layer, an inorganic layer which conducts electrons, one or several optoelectronically active layers with at least one light-emitting layer which comprises an organic emitter, and a second electrode layer. The inorganic layer which conducts electrons is an N-type conducting oxide of a transition metal chosen from the group consisting of zirconium oxide, hafnium oxide, vanadium oxide, barium titanate, barium-strontium titanate, strontium titanate, calcium titanate, calcium zirconate, potassium tantalate, and potassium niobate.

Organic electroluminescent component with charge transport layer

A luminescent screen includes a luminescent zeolite containing rare earths, such as terbium (Tb), and europium (Eu), and an oxide of a transition metal, such as, molybdenum (Mo), tungsten (W), niobium (Nb), and tantalum (Ta). It was found that a zeolite containing both terbium, and tungsten oxide had an absorbability that was approximately 60 times as high as that of a zeolite containing only terbium, thus increasing the luminescent efficiency of the zeolite.

Luminescent screen including a luminescent zeolite

The invention relates to a luminescent zeolite of the Faujasite type containing Ce.sup.3+ ions. Such a zeolite can for instance be used in the luminescent screen of a low pressure mercury discharge lamp for use in photochemical processes. According to the invention the zeolite further contains cations S.sup.n+, wherein n.gtoreq.2 and the sum of the amount of Ce.sup.3+ ions and the amount of cations S.sup.n+ per unit cell of the zeolite is at least 16. The zeolite exhibits a high quantum efficiency for converting UV radiation of 254 nm into radiation having an emission maximum between 315 and 400 nm, even in case the Ce.sup.3+ ion content is relatively low.

Luminescent zeolite

An organic electroluminescent component with a layer structure comprising

Organic electroluminescent component

The invention relates to a luminescent screen and to a low pressure mercury discharge lamp comprising such a luminescent screen. According to the invention the luminescent screen comprises a zeolite containing trivalent Ce. The luminescent screen exhibits a large quantum efficiency for converting UV radiation of 254 nm into radiation having an emission maximum at approximately 346 nm.

Luminescent screen

The invention relates to a luminescent zinc sulphide of cubic structure (sphalerite) which is so activated by aluminum and copper that a green-emitting luminescent material is created. In a simple manufacturing process, high x-values of the colour point and high luminous efficacy values are achieved in that copper is added in a quantity of 200 to 450 mole ppm and aluminum in a quantity of 700 to 2000 mole ppm.

Green-luminescing zinc sulphide and cathode ray tube provided with this

The invention relates to a method of coating red-luminescing phosphor particles with hematite (.alpha.--Fe.sub.2 O.sub.3), whereby first Fe(OH).sub.3 is deposited on the phosphor particles and subsequently converted into .alpha.--Fe.sub.2 O.sub.3 at a raised temperature. A good adhesion of the hematite pigments to the phosphor particles is achieved in that first an aqueous solution of an iron(III) salt and a complexing agent is prepared, in which the complexing agent and its concentration are so chosen that in combination with Fe.sup.3+ ions complex ions are formed which on the one hand do not yet precipitate at a pH-value which is at least 0.5 higher than the value at which the phosphor particles just fail to be chemically attacked anymore, and which are dissociable at a further increase in the pH-value so that Fe(OH).sub.3 is formed, in that subsequently, if the pH-value is not yet high enough, a basic substance is added to the mixture, in that the pH-value is increased to a value which is at least 0.5 below the value at which Fe(OH).sub.3 starts to precipitate and at least 0.5 higher than the value at which the phosphor particles just fail to be chemically attacked anymore, in that subsequently the phosphor particles are added while stirring, in that at any moment, as required, a substance is added which dissociates upon an increase in temperature and which behaves as a base upon dissociation, and in that then the temperature of the suspension is slowly increased, whereby the phosphor particles are coated with Fe(OH).sub.3 through homogeneous precipitation.

Method of coating red-luminescing phosphor particles with hematite

The luminescent phosphor degradation in a cathode ray display tube, caused by aging, is decreased. This decrease is achieved by introducing before and/or during evacuation a hydrolyzable gas into the tube's inner space for a limited time interval, using a partial pressure which is essentially larger than the eventual final vacuum pressure of the cathode ray tube, and then allowing the final vacuum pressure to be achieved without any further supply of gas. Thereafter, the cathode ray tube is sealed in a gastight manner.

Growing community of inventors

Roetgen, Germany

Ulrich H Kynast