Abstract: A radiation image storage panel comprises at least a substrate and a phosphor layer overlaid upon the substrate. The phosphor layer contains a binder, a phosphor, and at least one kind of organic phosphorus compound represented by Formula (1): (R)nPO(OM)3−n  (1) in which R represents an alkyl group, an aryl group, or a heterocyclic group, which may be optionally substituted by a substituent; M represents a hydrogen atom, an alkali metal, or —N+(R1)4, where R1 represents an alkyl group having at most two carbon atoms; and n represents an integral number of 1 or 2. The radiation image storage panel exhibits enhanced dispersibility of phosphor particles and a high sensitivity and yields little noise.

Abstract: A metallic compound layer exhibiting a photocatalytic activity function is formed on the surface of light absorbing material so as to provide the property of deodorizing air or an object coming in contact with the material. Preferably, the metallic compound layer is fixed on the surface of the light absorbing material. Alternatively, the metallic compound layer is formed as a material in which the surface region includes an outer portion mainly formed of a metallic mixture including a metallic oxide, such as titanium oxide. As a method of manufacturing the light absorbing material is coated with a metallic compound for improving photocatalytic activity, and then is processed into a desired shape.

Abstract: Interference pigment flakes and foils are provided which have luminescent and color-shifting properties. A luminescent material coating structure is provided which partially covers or encapsulates a color-shifting pigment flake, or covers the outer surface of a foil. The pigment flakes can have a symmetrical coating structure on opposing sides of a core layer, can have an asymmetrical coating structure with all of the layers on one side of the core layer, or can be formed with encapsulating coatings around the core layer. The coating structure of the flakes and foils includes a core layer, a dielectric layer overlying the core layer, and an absorber layer overlying the dielectric layer. The luminescent pigment flakes and foils exhibit a discrete color shift so as to have a first color at a first angle of incident light or viewing and a second color different from the first color at a second angle of incident light or viewing.

Abstract: An ink for a display panel that at a time of application is a mixture of a powder material, a water-soluble resin included in a range of 1 wt % to 20 wt % inclusive of the ink, and a water-miscible solvent. The ink is water-soluble, and in comparison to conventional organic inks, the ink of the present invention exhibits a markedly reduced susceptibility to the occurrence of electrostatic action. Thus, even when the ink is discharged through a plurality of fine nozzle holes, for example, it is possible for the application process to be conducted with great efficiency, since the individual ink flows discharged from the nozzle holes flow in a vertically downward direction without reacting with each other and becoming warped as a result. The ink of the present invention may, for example, be a phosphor ink, an Ag electrode ink, a shading film (black matrix) ink, a sealant glass ink, or a white reflective layer ink, and the ink may be used in forming structural layers of a display panel.

Abstract: A method is provided for applying an internal coating to a fluid conduit component before assembly of that component in a fluid circuit. A selected amount of coating material is placed into a measuring device and dispensed into an opening of the component to coat an interior surface of the component. The coating material may be a leak detection dye or other additive that is later dissolved when the component is installed in a system of components such as an air conditioning system. When the system is charged with refrigerant and lubricant, the dye dissolves and may be circulated by the refrigerant and lubricant. If a leak exists in the system, the dye is expressed to indicate the location of a leak site. An apparatus is also provided for applying dye to an interior surface of a component of an air conditioning unit, prior to assembly of the component in an air conditioning system.

Abstract: A retroreflective coating system and a method of providing the coating system on a substrate are disclosed. The method includes applying a color-providing composition, such as a pigmented basecoat composition, and applying a clearcoat composition. After application and cure, the color-providing composition forms a color-providing film layer, and the clearcoat composition forms a clearcoat film layer. The color-providing composition and the clearcoat composition are cross-linkable. Either one, or both, of the color-providing composition and the clearcoat composition include retroreflective microspheres. The color-providing composition is applied to the substrate to form an uncured film layer of the color-providing composition. Next, the clearcoat composition is applied wet-on-wet to the uncured film layer of the color-providing composition such that an uncured film layer of the clearcoat composition is formed on the uncured film layer of the color-providing composition.

Abstract: A phosphorescent coating system and a method of providing the coating system on a substrate are disclosed. The method includes applying a color-providing composition, such as a pigmented basecoat composition, and applying a clearcoat composition. After application and cure, the color-providing composition forms a color-providing film layer, and the clearcoat composition forms a clearcoat film layer. The color-providing composition and the clearcoat composition are cross-linkable. Either one, or both, of the color-providing composition and the clearcoat composition include phosphorescent pigment. The color-providing composition is applied to the substrate to form an uncured film layer of the color-providing composition. Next, the clearcoat composition is applied wet-on-wet to the uncured film layer of the color-providing composition such that an uncured film layer of the clearcoat composition is formed on the uncured film layer of the color-providing composition.

Abstract: A composition for a fluorescent marking paste or paint that is non-toxic, water soluble, clear drying and safe for nonporous surfaces is disclosed. The invention is composed of a generic white school paste or any other water soluble, non-toxic, clear drying paste or cement to which non-toxic fluorescent or phosphorescent colorant particles and water are added. The consistency of the resultant mixture is either a paste for making an impression or a paint for applying to a non-porous object using a brush, and the paste or paint, when dry, is clearly visible under UV light. Unique identifying marks such as identifying stamps, actual fingerprints, or numbers may be placed on any nonporous object that can be safely cleaned with a damp cloth. This invention provides a safe marking system for allowing e-commerce sellers to prevent buyer fraud or for allowing owners to identify possessions for inventory and insurance purposes.

Abstract: A method of forming a fluorescent screen where a pigment film and a fluorescent film are deposited on a surface of a light transmissive substrate, the method comprising: coating a pigment dispersion liquid on the surface of the light transmissive substrate to form a coated film; and forming a pigment film by drying the coated film; wherein drying of the coated film is performed under the conditions that a temperature of corner portions of the light transmissive substrate is controlled to not lower than 36° C., or that drying means which is exclusively assigned to dry the corner portions of the coated film is employed.

Abstract: The invention aims to provide a phosphor thin film eliminating a need for filters, having a satisfactory color purity, suited for RGB in full-color EL displays, enabling to simplify the manufacture process of full-color EL panels, and offering the advantages of minimized variation of luminance, increased yields, and reduced manufacture cost, a method for preparing the same and an EL panel. Such objects are achieved by a phosphor thin film formed of a matrix material comprising an oxysulfide consisting of at least one compound selected from rare earth thioaluminates, rare earth thiogallates and rare earth indates, in which oxygen is incorporated, the matrix material further containing an element serving as a luminescent center, a method for preparing the same, and an EL panel using the same.

Abstract: A method of manufacturing an organic EL element according to the present invention comprises the steps of forming pixel electrodes (801), (802), (803) on a transparent substrate (804) and forming on the pixel electrodes by patterning luminescent layers (806), (807), (808) made of an organic compound by means of an ink-jet method. According to this method, it is possible to carry out a high precise patterning easily and in a short time, thereby enabling to carry out optimization for a film design and luminescent characteristic easily as well as making it easy to adjust a luminous efficiency.

Abstract: A luminescent coating compound of organic binder and luminescent fibers containing at least one organic binder and fibers which of a fiber-forming material with at least one luminescent dye or pigment distributed therein. Also a process of producing coatings of such compounds and articles with such coatings.

Abstract: This patent disclosure describes novel compositions and methods used in the verification of products or documents based on the reading of emitted light from luminescent compositions that can be incorporated or applied to a wide variety of materials. Specifically, the compositions are uniquely luminescent at various wavelengths, displaying qualities of image, wavelength, and time scale for the measure of luminesce decay. The light emitted from the composition, and specifically, the measure of the variable and adjustable luminescence lifetimes provides a multi-parameter signature for purposes of comparative light decay analysis of verification marks or features.

Abstract: Organic luminescent ink (L-ink) is disclosed for use in printing thin films of organic luminescent material. The L-ink is particularly useful in fabricating organic optoelectronic devices, e.g. organic luminescent devices. The L-ink contains at least one organic luminescent material mixed with a solvent and other functional additives to provide the necessary optical, electronic and morphological properties for light-emitting devices (LEDs). The additives play an important role either for enhanced thin film printing or for better performance of the optoelectronic device. The functional additives may be chemically bound to the luminescent compounds or polymers. Luminescent organic compounds, oligomers, or polymers with relatively low solution viscosity, good thin film formability, and good charge transporting properties, are preferred. The L-inks can be cross-linked under certain conditions to enhance thin film properties.

Abstract: In a method of and an arrangement for producing a fluorescent layer on a substrate (12), being supported by a substrate holder (11), the temperature of the substrate (12) and of the substrate holder (11) is controlled by introducing a gas into a cavity (14) between the substrate and the substrate holder in order to realize a thermal coupling between the substrate and the substrate holder.

Abstract: This invention relates to self-luminescent signage and indicia, particularly suited to architectural applications. This invention uses stencils, or other guiding devices, an applicator and an alkali earth oxide aluminate luminescent paint to create indicia that absorb ambient light and emit it in the darkness. This eliminates the need for separately powered emergency signage or other luminescent or illuminated indicia.

Abstract: The invention aims to provide a phosphor thin film eliminating a need for filters, having a satisfactory color purity and useful as the blue color in full-color EL displays, a method for preparing the same and an EL panel. Such objects are achieved by a phosphor thin film formed of a matrix material comprising barium thioaluminate as a main component to which magnesium is added and rare earth element, Eu is added as a luminescent center, a method for preparing the same, and an EL panel using the same.

Abstract: Making a phosphor screen by forming a phosphor powder that incorporates strontium, is made up of particles having a long dimension of less than about 5 microns and having superior response time. Slurrying the phosphor powder with a suitable solvent, dispersant, plasticizer and binder. Coating a suitable substate with an infra red absorbing layer. Coating the phosphor containing slurry onto the infra red absorbing layer. Drying the thus produced screen.

Abstract: A coating composition comprising at least a stimulable phosphor, a binder, and a mixed solvent is prepared. The mixed solvent comprises a low boiling temperature solvent having a viscosity of at most 0.6 mPa·s and a high boiling temperature solvent having a viscosity higher than 0.6 mPa·s, boiling temperatures of the low boiling temperature solvent and the high boiling temperature solvent being different by at least 10° C. from each other. The coating composition is applied onto a substrate and dried, and a stimulable phosphor layer is thereby formed on the substrate. The boiling temperature of the low boiling temperature solvent may be at most 110° C., and the boiling temperature of the high boiling temperature solvent may fall within the range of 110° C. to 220° C. The thus formed stimulable phosphor layer has uniform stimulable phosphor density, and a radiation image storage panel exhibiting little nonuniformity in light emission is capable of being produced.

Abstract: A method of manufacturing a multi-layer optical information carrier with fluorescence reading/recording is presented. A structure is fabricated, being formed of a substrate carrying a fluorescent film on one or both surfaces thereof, wherein the substrate is transparent with respect to incident radiation used for the fluorescence reading/recording. A patterned structure is applied to the fluorescent film under predetermined process conditions, such as to produce a fluorescent patterned structure with a surface relief in the form of an array of discrete fluorescent regions. The same procedure is repeated a required number of times, so as to obtain at the end of the process a multi-layer optical information carrier.

Abstract: A phosphor is prepared by depositing a compound semiconductor of Groups III-V in the form of fine particles or a thin film on a surface of a carrier particle by hetero-epitaxial growth. Thus, the phosphor increased in quality is obtained with satisfactory reproducibility.

Abstract: A fluorescent thin film is provided, comprising a matrix material containing as a main component a rare earth sulfide or a rare earth selenide and a rare earth element added thereto as a light emission center. The rare earth element is different from a rare earth element used for said matrix material.

Abstract: A radiation image storage panel comprises at least a substrate and a phosphor layer overlaid upon the substrate.

Abstract: A manufacturing process for a lead-frame forming material, comprises continuously subjecting a metal web to a degrease treatment and an acid cleaning treatment, coating a light-sensitive material on said metal web, followed by drying to form a light-sensitive layer, and cutting the above coated lead-frame forming metal web thus obtained in fixed lengths along a longitudinal direction or winding said coated lead-frame forming metal web into a roll. The lead-frame having a uniform quality can be produced in large volume.

Abstract: Methods of forming face plate assemblies are described. In one implementation, a substrate is patterned with photoresist and a first phosphor-comprising material is formed over first surface areas of the substrate. The photoresist is stripped leaving some of the first phosphor-comprising material over substrate areas other than the first areas. Photoresist is again formed over the substrate and processed to expose second substrate areas which are different from the first substrate areas. In a preferred aspect, processing the photoresist comprises using a heated aqueous developing solution comprising an acid, e.g. lactic acid, effective to dislodge and remove first phosphor-comprising material from beneath the developed photoresist. A second phosphor-comprising material is formed over the substrate and the exposed second areas, with trace deposits being left over other substrate areas.

Abstract: An apparatus for electrostatically coating powder on a flat panel and a method for using such apparatus are provided. In the apparatus, a heating device is used to heat a panel to be coated and positioned on a powder spray chamber to a temperature of at least 100° C. and simultaneously charging the panel with a negative voltage of at least 20,000 volts. The high temperature and the high voltage of the otherwise non-conductive panel result in a panel that is electrostatically conductive. Powder particles that are charged with a high positive voltage are then injected toward the panel surface by an air pressure of at least 0.8 kg/cm2 until particles are adhered to the panel surface. The present invention novel method can be used advantageously at low costs due to its simple processing steps and as an environmentally friendly process since no solvent needs to be evaporated and released into the atmosphere.

Abstract: The invention describes the particles comprising an energy donor as a first component and a fluorescent dye as a second component positioned in said particles at an energy exchanging distance from one another, wherein the two components have a Stokes shift of greater than or equal to 50 nm, said particle having bound on its surface, a protein, polypeptide, nucleic acid, nucleotide or protein containing ligand analogue are disclosed and claimed. In addition, novel fluorescent dyes are described which exhibit intramolecular energy transfer for use to label various molecules, proteins, polypeptides, nucleotides and nucleic acids or to incorporate into particles.

Abstract: A coating liquid for forming an organic LED layer which is used for forming an organic LED layer of an organic LED device by an inkjet method, comprising at least: a solvent and an organic material having a weight-average molecular weight less than 600,000.

Abstract: An optical fluorescent composite which controls fluorescence intensity comprises a solid layer containing fluorescent material (such as a phosphor) formed on an optically transparent base or substrate and optically coupled to a spectrally selective filter, also formed on the base or substrate, that modifies the intensity of either or both the excitation or emission spectra of the phosphor. Devices constructed in this manner serve as stable references for fluorescent measurements. Sets of such device is made with filters having different transmittance amplitudes, can characterize fluorescent measurement response over several orders of magnitude. In one of numerous alternative structure, the fluorescent layer can be formed on one substrate, the filter formed on a second substrate and the two substrates joined together.

Abstract: A pigment composition includes a crystalline thermoplastic polyester resin having residues of at least one dicarboxylic acid and a near-infrared fluorescing compound having a fluorescence between about 650 nm to about 2500 nm associated with the crystalline thermoplastic polyester, wherein the polyester has an intrinsic viscosity (IV) of less than about 0.37. A preferred polyester is polybutylene terephthalate. Another aspect is a method for providing a detectable or identifiable marking that is invisible to the unaided eye on a surface of a substrate is also provided. The method includes the steps of applying to the surface a marking composition comprising a suitably compatible marking fluid containing the fluorescent pigment composition. The near infrared fluorescing pigment composition is useful in letterpress, flexographic and gravure printing applications.

Abstract: The present invention provides a method for reducing undesirable light emission from a sample using at least one photon producing agent and at least one photon reducing agent (e.g. dye-based photon reducing agents). The present invention further provides a method for reducing undesirable light emission from a sample (e.g., a biochemical or cellular sample) with at least one photon producing agent and at least one collisional quencher. The present invention also provides a method for reducing undesirable light emission from a sample (e.g., a biochemical or cellular sample) with at least one photon producing agent and at least one quencher, such as an electronic quencher. The present invention also provides a system and method of screening test chemicals in fluorescent assays using photon reducing agents. The present invention also provides compositions, pharmaceutical compositions, and kits for practicing these methods.

Abstract: Fibers having at least one near-infrared fluorescing compound associated therewith are prepared by contacting the fibers with the fluorescing compound(s) dissolved in an organic solvent. Suitable organic solvents include ketones and alcohols. The fibers may subsequently be air-dried to remove any remaining volatiles. Fibers coated with the marker solution desirably have less than 1 weight percent of the marker coated thereon.

Abstract: The present invention provides a method for reducing undesirable light emission from a sample using at least one photon producing agent and at least one photon reducing agent (e.g. dye-based photon reducing agents). The present invention further provides a method for reducing undesirable light emission from a sample (e.g., a biochemical or cellular sample) with at least one photon producing agent and at least one collisional quencher. The present invention also provides a method for reducing undesirable light emission from a sample (e.g., a biochemical or cellular sample) with at least one photon producing agent and at least one quencher, such as an electronic quencher. The present invention further provides a method of determining bound and free analyte in a sample using at least one photon reducing agent. The present invention also provides a method of screening test chemicals in fluorescent assays using photon reducing agents.

Abstract: The present invention provides a method for reducing undesirable light emission from a sample using at least one photon producing agent and at least one photon reducing agent (e.g. dye-based photon reducing agents). The present invention further provides a method for reducing undesirable light emission from a sample (e.g., a biochemical or cellular sample) with at least one photon producing agent and at least one collisional quencher. The present invention also provides a method for reducing undesirable light emission from a sample (e.g., a biochemical or cellular sample) with at least one photon producing agent and at least one quencher, such as an electronic quencher. The present invention further provides a method of determining bound and free analyte in a sample using at least one photon reducing agent. The present invention also provides a method of screening test chemicals in fluorescent assays using photon reducing agents.

Abstract: A presentation is given of an improved method for coating lamp tubes for gas discharge lamps and for drying the coating, as well as of a device designed for the method, in the case of which method and device, during coating and drying, the lamp tubes are arranged at an oblique angle to the horizontal.

Abstract: The present invention provides suspensions and methods for depositing luminescent materials (e.g., phosphors) using electrophoresis, particularly during the preparation of display devices, such as field emission display devices, and the articles produced thereby. The luminescent material is deposited onto a substrate having thereon a metal-containing transparent, conductive coating. The suspension includes a nonaqueous liquid, a luminescent material, and a salt of a metal of the transparent, conductive coating.

Abstract: A method for making a optical sensor for measuring the pH of a fluid includes the steps of applying a solution containing (a) a cellulose acrylamide, (b) an acrylamide, and (c) a copolymerizable monomeric fluorescent indicator species to the distal end of an optical fiber and polymerizing the solution to form a pH sensor means.

Abstract: A method for making a fiber optic sensor includes the steps of applying an adhesive composition to the distal end of an optical fiber, and applying a solution containing a copolymer of (a) a cellulose acrylamide, (b) an acrylamide, and (c) a copolymerizable monomeric fluorescent indicator species thereto to form a sensing layer.

Abstract: A method of manufacturing a luminescent article comprising a self-supporting or supported phosphor containing layer having thereon a protective coating, said method comprising the step of applying on top of said phosphor containing layer a radiation-curable liquid coating composition having at the coating temperature a viscosity of at least 450 mPa.s, the viscosity at that temperature being measured with a Hoeppler viscometer.

Abstract: A black matrix material for increasing resolution and contrast of field emission displays is disclosed. The black matrix material is preferably deposited by electrophoresis in the interstitial regions between phosphor pixels of the faceplate. By this technique, high resolution and/or small surface area field emission displays may be manufactured. The black matrix material does not brown when subjected to the conditions associated with the manufacture of field emission displays, is chemically inert and remains stable under vacuum conditions and electron bombardment. The black matrix material is selected from boron carbide, silicon carbide, tungsten carbide, vanadium carbide and mixtures thereof.

Abstract: A method for producing a phosphor made of luminous inorganic particles of a nanostructure which is capable of keeping a surface of the phosphor from being polluted by any by-product and controlling a particle diameter distribution of the phosphor as desired. A carbon material and an inorganic salt are mixed together to prepare a mixture, which is then heated, to thereby form an interlaminar compound. Then, the interlaminar compound is subject to a treatment using an eliminating agent, leading to production of luminous inorganic compound particles adhered to the carbon material.

Abstract: An electroluminescent device improved in brightness is disclosed. The electroluminescent device comprising sequentially stacked layers having an optically transparent material on at least the viewing side of the structure comprises a luminescent layer based on a Group II-III-VI compound host material with an element acting as a luminescent center added therein, wherein a Group II element having an ion radius differing from that of the Group II element constituting the compound host material is further added in the luminescent layer.

Abstract: A process for authenticating a medium which can be solid or liquid in which particles of an organic composition capable of absorbing or reflecting infrared or near-infrared radiation are incorporated in the medium. The transparent or opaque state can be irreversibly selected upon heating to a temperature greater than ambient temperature or to ultraviolet radiation and, whether or not particles are opaque can then be determined.

Abstract: A phosphor comprises, in atomic percentages, 90% to 100% of a mixed metal oxide MxTyOz, wherein M is a metal selected from Zn, Sn, In, Cu, and combinations thereof, T is a refractory metal selected from Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W, and combinations thereof, and O is Oxygen, x, y, and z being chosen such that z is at most stoichiometric for MxTyOz; and 0% to 10% of a dopant comprising a substance selected from a rare earth element of the lanthanide series, Mn, Cr, and combinations thereof, or stoichiometrically excess zinc, copper, tin, or indium. Cathodoluminescent phosphor compositions stimulable by electrons of very low energy are prepared from metal oxides treated with refractory metals in various processes disclosed.

Abstract: A black matrix material for increasing resolution and contrast of field emission displays is disclosed. The black matrix material is preferably deposited by electrophoresis in the interstitial regions between phosphor pixels of the faceplate. By this technique, high resolution and/or small surface area field emission displays may be manufactured. The black matrix material does not brown when subjected to the conditions associated with the manufacture of field emission displays, is chemically inert and remains stable under vacuum conditions and electron bombardment. The black matrix material is selected from boron carbide, silicon carbide, tungsten carbide, vanadium carbide and mixtures thereof.

Abstract: A method for processing a single-crystal semiconductor wafer is provided which is capable of minimizing a dead space to maximize the number of elements per one wafer and preventing leakage luminescence and a reduction in luminance. A phosphor is deposited on each of a plurality of regions defined in the wafer at predetermined intervals and a water-resistant protective film is formed on the phosphor. Then, the wafer is cut for every one of the regions by means of a dicing saw using cutting water, to thereby provide a plurality of chips. The chips are subject to calcination during a calcination step in manufacture of fluorescent display device in which the chips are used as a display section, resulting in the protective film being evaporated.

Abstract: The present invention is directed to a method for labeling an object for its identification in order to counter product diversion and product counterfeiting. This method includes providing an encapsulated biologic marker labeled with an agent that emits selected detectable wavelengths of energy when exposed to infrared radiation (IR), and associating the labeled marker with the object, whereby, the object to be identified can be exposed to IR and emitted select wavelengths of energy from said agent detected. The agent can be an upconverting phosphor, a lanthenide ion (bound to a naphthalene group), or other chemical that emits selected detectable wavelengths of energy when exposed to infrared radiation (IR). Biologic markers include, inter alia, one or more of a protein, a nucleic acid sequence, an antibody, a polypeptide, or an antigen. The encapsulant for the biologic marker preferably is casein which has been cross-linked with itself.

Abstract: A process for manufacturing a phosphorescent screen for use in a cathode ray or field emission display, is described. The phosphor layer is applied in the form of a slurry consisting of a powdered phosphor, an ethylene glycol monobutyl ether acetate solvent, and a cellulose acetate butyrate binder. The phosphor concentration is between 30 and 60% by weight, the solvent between 5 and 52.5% and the binder between 17.5 and 35%. If the slurry composition falls within these ranges, then, once the aluminum anode layer is in place, all organic material can be removed by firing at a temperature that is less than 500.degree. C. By keeping the firing temperature below 500.degree. C., roughening of the undersurface of the aluminum is avoided and a more efficient screen is obtained. Data to illustrate this is also provided.

Abstract: In order to prevent or at least render difficult the copying of colored printed security papers, for example banknotes, the printing inks used for printing are so formulated that copies made using customary color copiers produce a markedly different color impression and can therefore easily be identified as being forgeries. This is achieved by using for the formulation of the printing inks dyes (pigments) that are as different as possible from the dyes (toners) customarily used in conventional color copiers. The choice of the dyes for the formulation of the printing inks is especially such that there is the greatest possible degree of metamerism between the printing ink in question and the match of the relevant master color using the dyes of the color copier. Preferably non-amorphous or anisotropic black dyes and effect dyes, especially fluorescent effect dyes, are co-used for the formulation of the printing inks.

Abstract: A method of manufacturing a phosphor composition of a phosphor comprising a pigment coating of hematite, includes a first step in which the phosphor is coated with an iron-containing starting compound for hematite, and a second step, in which the phosphor with the coating is calcined, thereby converting the iron-containing starting compound for hematite into hematite. The calcining operation is carried out in an atmosphere of a gas mixture of water vapor and an oxidizing gas.