Bundesdruckerei Gmbh

Leuchtstoffwerk Breitungen Gmbh

Bundesdruckeri Gmbh

Monika Voh

Detlef Starick

Manfred Paeschke

Andreas Deichsel

Benedikt Ahlers

Arnim Franz-Burgholz

Frank Kappe

Sylke Rösler

Florian Peters

Sven Rösler

Matthias Koch

Guido Haussmann

Roland Heise

Christian Kunath

Jakob Kuen

Sven Roesler

Hans-Jürgen Limburg

Adrie Bos

A security feature is presented for a security or value document. The security feature comprises a zinc sulfide luminophore in the form of particles. The zinc sulfide luminophore has the general chemical formula ZnS:Cu, M, X; here, M represents one or more elements from a group comprising the chemical elements Co, In and Ni; X represents one or more elements from a group comprising the halides F, Cl, Br and I; and the following applies: 0<x<0.002 and 0::; y<0.00015 and 0::; z<0.00050. The particles each have cubic phase portions and hexagonal phase portions. When excited by an electrical field, the zinc sulfide luminophore emits a first radiation in the range of the light spectrum between 580 nm and 780 nm. When excited by heating the luminophore to a temperature between 100° C. and 150° C., the zinc sulfide luminophore emits a second radiation in the light spectrum.

Security feature and method for the detection thereof, and security or value document

The present invention firstly relates to a security feature for a security or value document. The security feature comprises a zinc sulfide luminophore in the form of particles. The zinc sulfide luminophore has the general chemical formula ZnS: Cu, M, X; here, M represents one or more elements from a group comprising the chemical elements Co, In and Ni; X represents one or more elements from a group comprising the halides F, Cl, Br and I; and the following applies: 0<x<0.002 and 0≤y<0.00015 and 0≤z<0.00050. The particles each have cubic phase portions and hexagonal phase portions. When excited by an electrical field, the zinc sulfide luminophore emits a first radiation in the range of the light spectrum between 580 nm and 780 nm. When excited by heating the luminophore to a temperature between 100° C. and 150° C., the zinc sulfide luminophore emits a second radiation in the light spectrum. Furthermore, the invention relates to a security and value document, which may for example be a bank note or a passport, an identity card, a driving license or a postage stamp. The invention also relates to a method for detecting and/or verifying the security feature according to the invention.

The present invention relates to a zinc sulphide phosphor and to a process for producing same. The invention further relates to a security document or document of value, to a security feature and to a method for detecting same. The phosphor according to the invention can act as electroluminescent phosphor and thus be excited by an electrical field, and this can result in emission of electroluminescent light in the blue and/or green color region of the visible spectrum. The phosphor can moreover be excited by UV radiation in the wavelength range than 345 nm to 370 nm, and can thus emit photoluminescent light in the blue color region of the visible spectrum. The phosphor can moreover be excited by UV radiation in the wavelength range from 310 nm in 335 nm, and can thus emit photoluminescent light in the green color region of the visible spectrum.

Zinc sulphide phosphor having photo- and electroluminescent properties, process for producing same, and security document, security feature and method for detecting same

Zinc sulfide electroluminophores are prepared from solutions of zinc salts with hydrogen sulfide. The zinc sulfide compounds are mixed with activator and coactivator compounds to produce luminophores, and the mixtures are fired in the presence of fixing agents. These fired materials are then treated in an acid bath, washed, neutralized, and optionally filtered and dried.

Zinc sulfide electroluminophores and method for production thereof

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Breitungen, Germany

Monika Voh