Abstract: Oxygen ions are partially implanted into a semiconductor substrate 1 to form an oxygen ion implantation area. Then, a trench 2 surrounding the oxygen ion implantation area is formed in the semiconductor substrate 1 so as to remove the outer peripheral portion of the oxygen ion implantation area. Then, the semiconductor substrate 1 are heat treated to turn the oxygen ion implantation area into a buried oxide film 4 which is stable. Then, an insulating film 3 is buried into the trench 2.

Abstract: The present invention relates to phosphors, composition containing phosphors and methods of their use. More particularly, it relates to organic phosphors which are amino acid salts compositions containing the phosphors and methods of using those phosphors and compositions to make objects photo-luminescent.

Abstract: In process for forming a coating of phosphor particles on a fluorescent lamp glass, a polymer is deposited on the phosphor particles and the phosphor particles are entrained in a carrier gas with the polymer in a non-adhering state, and then the phosphor particles are coated on the fluorescent lamp glass with the polymer in an adhering state for retaining the phosphor particles on the fluorescent glass and, the coated fluorescent glass is heated to a temperature above the decomposition temperature of the polymer for removing the polymer and to form a coating of phosphor particles on a fluorescent lamp glass.

Abstract: A fluorescent lamp having a non-fluorescent substance layer and a phosphor layer laminated and coated on, or having a fluorescent composition composed of a mixture of a non-fluorescent substance and a phosphor, coated on the inner wall of a glass bulb, wherein the non-fluorescent substance is an oxide containing at least one rare earth element selected from the group consisting of yttrium, gadolinium and lanthanum.

Abstract: The present invention relates to a novel cost efficient luminescent composition comprising particles of a core material which have been coated with a luminescent material that is distributed in the form of a chemically homogeneous layer. The average diameter of the core particle is in the range of from about 0.5 to 20 microns, and the coating corresponds to between about 2 and 30 wt % of the total composition. One aspect the invention relates to a process for preparing the composition which comprises decomposing chelated metal luminescent compositions in solution at a relatively high pH while in the presence of dispersed core particles, thereby coating the core particles with hydrous metal oxides, recovering the coated particles, optionally washing the coated particles substantially free from soluble species, drying and calcining. In another aspect, a hydrous oxide coating is converted to a sulfide coating by treating the hydrous coating with a source of active sulfur.

Abstract: A method for coating a fluorescent lamp with an aqueous suspension of a multi-component phosphor blend wherein the isoelectric point(IEP) of at least one of the individual phosphors is separated by at least two pH units from the effective IEP of the other phosphors. The method involving altering the IEP of the first phosphor to within about two pH units of the effective IEP of the other phosphors, adding the modified phosphor to an aqueous suspension of the other phosphors, the aqueous suspension having a pH outside the range defined by the modified IEP and the effective IEP to inhibit flocculation, and coating a fluorescent lamp.

Abstract: A method for providing an electric field having a desirable configuration and strength for the electrostatic coating of phosphors on a fluorescent glass envelope at a controlled temperature comprising enclosing a fluorescent glass envelope with at least one electrically conductive charge retaining member at a desired temperature for the duration of the actual electrostatic coating operation wherein charged phosphor particles are attracted to the interior of the glass envelope and the charge is dissipated to the charge retaining member which remains substantially electrically isolated during the coating process. The process is most suitable adapted to an asymmetric fluorescent glass envelope.

Abstract: A thin film, intagliated phosphor screen structure includes an optical fiber bundle in which each of the fibers has its glass core etched below the level of its cladding sheath at the internal surface of the screen, and a phosphor layer is deposited as a thin film which fills in the core recesses. Preferably, the upper surfaces of the phosphor layers are formed with a spherical or parabolic shape, which is obtained by surface tension when the phosphor film is annealed. The upper surfaces of the phosphor layers may also be finished by polishing. An aluminum reflective layer may also be coated on the phosphor layer. The bottom walls of the cores are preferably etched to be convex or concave to provide a lens effect. The intagliated phosphor screen can transmit 90% to 95% or more of the light generated in the phosphor layers, for an output gain factor of 5 or more over conventional phosphor screens.

Abstract: A fluorescent lamp comprising a sealed envelope, a pair of opposing electrodes, a fill of inert gas and mercury and a phosphor coating on the internal walls of the envelope wherein the coating contains as at least one element thereof particles of europium activated barium magnesium aluminate having an average particle size of about 4 micrometers, less than about 5% of the particles having a size greater than 15 microns and less than about 5% of the particles having a size less than about 1 micron, said particles having on the external surfaces thereof a coating of sub-micron aluminum oxide having a surface area of from about 80 to about 120 square meters per gram, said coating being sufficient to impart stir in quality to said phosphor.

Abstract: A method and apparatus for uniform application of a coating of fluorescent phosphors to tubes that have been bent into a serpentine shape, which includes dragging a hose and phosphor spray nozzle through the bends of the serpentine tube, thereby depositing a phosphor layer throughout the serpentine tube.

Abstract: In process for forming a coating of phosphor particles on a fluorescent lamp glass, a polymer is deposited on the phosphor particles and the phosphor particles are entrained in a carrier gas with the polymer in a non-adhering state, and then the phosphor particles are coated on the fluorescent lamp glass with the polymer in an adhering state for retaining the phosphor particles on the fluorescent glass and, the coated fluorescent glass is heated to a temperature above the decomposition temperature of the polymer for removing the polymer and to form a coating of phosphor particles on a fluorescent lamp glass.

Abstract: A method of coating the bulb wall of a low-pressure mercury vapour discharge lamp with a luminescent layer, whereby a monomer and an initiator are added to a suspension comprising at least a luminescent material and a binder before a layer of this suspension is provided, which monomer is polymerized after drying of the suspension layer in order to fix the luminescent material and the binder.

Abstract: A method of forming a partial protective coating on phosphor particles to improve initial power output and maintenance of fluorescent lamps made with the phosphor. The phosphor particles are fluidized in a bed and at least partially enveloped by a coating precursor material. Residence time of the phosphor particles in the fluidized bed is short so that the phosphor particles are only partially coated with the coating precursor material. The coating precursor material is reacted to form a protective coating over at least a portion of the surface of the phosphor particles. The partially-coated phosphor particles are then annealed to cause the protective coating to selectively cover at least a portion of certain sites on the surface of the phosphor particles.

Abstract: A fluorescent lamp including a lamp bulb which has been coated with phosphor powder which has been ground in an attritor to reduce the powder weight without loss in light output and light maintenance. A process to produce such a fluorescent lamp utilizes a particular sequence of steps including firing, milling, attritor milling, and washing to produce an improved stir-in alkaline earth halophosphate.

Abstract: A skin tanning fluorescent lamp having a coating of a uniform and homogeneous deflocculated physical mixture of a first and second phosphor where the first phosphor has a desired emission in the spectral region from about 320 to about 400 nanometers and the second phosphor has a desired emission in the spectral region from about 280 to about 320 nanometers, said first phosphor has a first isoelectric point at a first pH and the second phosphor has a second isoelectric point at a second pH. The first and said second pH form a range. The deflocculated coating is stabilized by deflocculating the first and second phosphors at a third pH sufficiently outside of range to produce a resulting coating consistently having desirable emission during production.

Abstract: A fluorescent lamp including, a bulb having an outer surface and an inner surface, discharge gas contained in the bulb and generating ultraviolet rays by a discharge thereof, a pair of electrodes provided to the bulb for generating the discharge, a phosphor film formed on the inner surface of the bulb and having a non-uniform thickness thereof, and an ultraviolet suppressing film for suppressing the ultraviolet rays formed to be faced with the phosphor film, characterized in that the ultraviolet suppressing film has non-uniform ability for suppressing ultraviolet rays penetrating the phosphor film in accordance with portions thereof to decrease the difference in the intensity of the ultraviolet rays emitted from the ultraviolet suppressing film.

Abstract: A stir-in fluorescent lamp phosphor is coated with a 1:1 ratio of latex polymer and fumed silica. The polymer-coated fluorescent lamp phosphor exhibits improved dispersability and wettability in aqueous and organic binder media which are used to apply fluorescent lamp phosphors to the inside walls of a fluorescent lamp envelope.

Abstract: Phosphor coatings for use in mercury discharge tubes and glass plates for illuminated signboards are provided by applying phosphor particles to a surface by means of a binder. The phosphor and an inorganic binder are suspended in a volatile fluid. The suspension is used to coat the surface. Evaporation at a temperature not exceeding 175.degree. C. is used to remove the volatile fluid.

Abstract: A method for preparing a specific zinc orthosilicate phosphor particle having a nonparticulate, conformal aluminum oxide coating wherein all of a manganese activator is present as manganese (II) and occupies zinc (II) sites includes the steps of blending a zinc source, a manganese (II) source, a silicon source, and a tungsten source in amounts in accordance with said formula with an amount of up to about 2 weight percent NH.sub.4 Cl and up to about 0.2 weight percent NH.sub.

Abstract: Phosphor particles are coated with a continuous, non-particulate, conformal coating of a metal oxide by suspending the phosphor particles in a gel solution containing a metal alkoxide. The gel suspension is then gelled after which the gelled suspension is dried, during which process the metal alkoxide is converted to metal oxide which coats the particles. Such coated phosphor particles can improve maintenance of lamps in which they are employed.

Abstract: The initial power output and maintenance of a fluorescent lamp containing europium-activated barium magnesium silicate phosphor is significantly improved by combining the phosphor with a flux and subjecting the phosphor/flux mixture to a refiring and rewashing process before applying the phosphor to the interior of a fluorescent lamp envelope. Surface concentrations of europium and barium are significantly increased, while surface concentrations of magnesium and silicon are decreased.

Abstract: A luminescent sheet for stamps comprising a subtrate and a luminescent layer formed on the surface of said substrate, characterized in that said luminescent layer contains fine particles of an inorganic fluorescent pigment, said fine particles being prepared by providing a dispersion containing particles having a mean specific surface area Sw.sub.2 of said inorganic fluorescent pigment in water, and subjecting said dispersion to wet-grinding to obtain an aqueous dispersion containing fine particles having a mean specific surface area Sw.sub.1 of said inorganic fluorescent pigment, and said fine particles satisfying the equation: 2.0.gtoreq.Sw.sub.1 /Sw.sub.2 .gtoreq.1.05.

Abstract: A an europium doped yttrium oxide red phosphor in a water base phosphor coating suspension is checked for degraded phosphor by (a) centrifuging the suspension, (b) separating an aqueous portion from a solids portion, (c) exposing a surface portion of said solids to UV radiation at 254 nm or 365 nm, (d) observing the presence or absence of fluorescence from said top layer of solids wherein the absence of fluorescence is indicative of a degraded phosphor.

Abstract: A method for eliminating carbonaceous contaminants and preventing the hydration/solubilization of the alumina protective coating of a phosphor is described. The method involves the heating a fluidized alumina coated phosphor in a fluidized bed at a temperature and for a period of time sufficient to preclude adversely affecting the protective oxide coating on the phosphor during subsequent water-based suspension processing without detrimentally altering the phosphor. After heating the fluidized phosphor is cooled and then added to a water-based suspension. The conditions for treating a manganese activated zinc silicate phosphor having a protective alumina coating are heating the fluidized phosphor at a temperature between about 700.degree. C. and about 850.degree. C. for a period of time from about 15 minutes to about 20 hours.A fluorescent lamp containing the phosphor prepared by the above described method is also described.

Abstract: A method of encasing a luminous translucent tubing (12,32) of a non-linear complex geometrical configuration in a transparent outer member (14,34) and forming a passage (25,35) of annular radial cross section therebetween, which method comprises coating the exterior of the tubing (12,32) with a viscous temporary material (17,47) which solidifies to provide a coating with smooth exterior surface, coating the temporary substance (17,47) with a permanent forming material in a viscous liquid state which hardens to form a rigid transparent outer member (14,34) in coextensive surrounding relation to the tubing (12,32) and its coating of temporary material (17,47), applying heat to said coating of temporary material at a temperature above the melting point of the temporary material and below the softening temperature of the outer member, and removing the temporary material from between the translucent tubing (12,32) and the transparent outer member (14,34) while supporting the translucent tubing in fixed relation to

Abstract: A method has been found which reduces substantially the degradation of the red phosphor, Y.sub.2 O.sub.3 :Eu, in water base fluorescent lamp suspension, thereby prolonging the shelf life of triphosphor suspensions. The method of the invention comprises forming a protective coating around individual particles of europium-doped yttrium oxide phosphor to inhibit degradation of europium-doped yttrium oxide phosphor in a water base phosphor coating suspension, the protective coating comprising an inorganic material and being of sufficient thickness to prevent the europium-doped yttrium oxide phosphor from reacting with the coating suspension. A preferred coating material is gamma-alumina.

Abstract: An apparatus for making an aperture in a coating on an inside surface of a lamp envelope such as a miniature fluorescent lamp envelope. The apparatus includes a magnetic scraping tool disposed adjacent to the inside surface of the lamp envelope and a magnet disposed adjacent to the outside surface of the lamp envelope so as to influence the scraping tool. The magnet acts on the magnetic scraping tool to maintain a scraping portion of the scraping tool in contact with the inside surface of the lamp envelope. As the magnet is moved along the outside of the lamp envelope, the scraping tool is pulled through the inside of the lamp envelope with sufficient clamping force to scrape a desired width of coating from the inside surface of the lamp envelope. In one embodiment, a guide is provided to guide the scraping tool through the lamp envelope. In a preferred embodiment, the scraping tool and the magnet are coupled to the guide. The guide moves the magnet and the scraping tool along the lamp envelope.

Abstract: The method of making a bi-layer coating on phosphor particles is disclosed. The first layer surrounding the phosphor is silica. The second layer surrounding the phosphor is alumina. The bi-layer phosphor is useful in fluorescent lamps providing improved maintenance and brightness. The bi-layer phosphor can also be used in high color rendition lamps employing blends of phosphors.

Abstract: Disclosed is a method for applying a continuous protective coating to the surface of individual phosphor particles. The method involves chemical vapor deposition of an aluminum oxide coating on individual particles of a phosphor powder while the particles are suspended in a fluidized bed. The particles in the fluidized bed are exposed to vaporized coating precursor material, preferably aluminum isopropoxide at a temperature above 300.degree. C. The bed is kept at as nearly an isothermal condition as possible. Prior to entering the fluidized bed the aluminum isopropoxide is vaporized and kept at a temperature less than the decomposition temperature of aluminum isopropoxide. Mechanical means are used to help increase the fluidization efficiency of the fluidized bed. After coating the phosphor particles for approximately 30 minutes the vaporized precursor material is shut off from the bed entrance and the oxygen flow rate to the fluidized bed is increased.

Abstract: A fluorescent lamp including a lamp bulb which has been coated with phosphor powder which has been ground in an attritor to reduce the powder weight without loss in light output and light maintenance. A process to produce such a fluorescent lamp is also provided.

Abstract: A coating suspension including negatively charged fine particles, water, a negative charge precursor, a defoaming agent, a surface active agent, an insolubilizing agent, a plasticizer, and two water-soluble binders is provided. In a preferred embodiment the fine particles are fine particle-size silica. There is also provided a method for coating a substrate with fine particles having a negative electrical charge. The method includes forming a coating suspension including the fine particles, water, a negative charge precursor, a defoaming agent, a surface active agent, an insolubilizing agent, a plasticizer, and two water-soluble binders; applying the coating suspension to the surface of the substrate to form a coated substrate; and heating the coated substrate to cure the coating and remove the water from the suspension. The coating formed is insoluble in water and water based media.

Abstract: Disclosed is a method for applying a continuous protective coating to the surface of individual phosphor particles. The method involves chemical vapor deposition of an aluminum oxide coating on individual particles of a phosphor powder while the particles are suspended in a fluidized bed. The particles in the fluidized bed are exposed to vaporized coating precursor material, preferably aluminum isopropoxide at a temperature above 300.degree. C. The bed is kept at as nearly an isothermal condition as possible. Prior to entering the fluidized bed the aluminum isopropoxide is vaporized and kept at a temperature less than the decomposition temperature of aluminum isopropoxide. Mechanical means are used to help increase the fluidization efficiency of the fluidized bed. After coating the phosphor particles for approximately 30 minutes the vaporized precursor material is shut off from the bed entrance and the oxygen flow rate to the fluidized bed is increased.

Abstract: The lumen maintenance of fluorescent lamps containing yttrium vanadate phosphors is markedly improved by the presence of a protective oxide layer for the phosphor. The protective oxide layer is produced by evaporating aluminum isopropoxide, in a vacuum, over phorphor particles forming a continuous aluminum isopropoxide over the phosphor particles. The isopropoxide coating is subsequently oxidized by lehring the phosphor at a temperature from about 500.degree. C. to 625.degree. C. forming an alumina coating on the phosphor particles.

Abstract: Water added to the furnace heated by an infrared or near-infrared radiation source used to fire thick-film electrical components provides finished components exhibiting desirable physical and electrical properties and surface cleanliness.

Abstract: A fluorescent lamp containing a Y.sub.2 O.sub.3 or Al.sub.2 O.sub.3 coating on a layer of yttrium vanadate phosphor and a method of coating the layer of the yttrium vanadate phosphor with a continuous protective coating of Y.sub.2 O.sub.3 or Al.sub.2 O.sub.3 is described. The method comprises applying a coating of a metal, such as yttrium or aluminum, on the yttrium vanadate phosphor then lehring the metallic coating at about 500.degree. C. to about 625.degree. C. to form a continuous protective coating of Y.sub.2 O.sub.3 or Al.sub.2 O.sub.3 overlaying the layer of phosphor.

Abstract: A method is disclosed for producing an aluminum oxide coated manganese activated zinc silicate phosphor which comprises forming a solution of Al.sup.+3 ions in water with the concentration of the aluminum being from about 0.01 to about 0.30 moles/l, adding manganese activated zinc silicate phosphor to the aluminum solution to form a slurry wherein the amount of phosphor is about 0.7 to about 1.0 moles per liter of slurry with agitation for a sufficient time to result in aluminum ions being adsorbed onto the surfaces of the particles of the phosphor, separating the resulting phosphor with adsorbed aluminum ions from the resulting liquor, drying the phosphor with the adsorbed aluminum ions, firing the resulting dried phosphor at a temperature of from about 750.degree. C. to about 850.degree. C.

Abstract: A method for making a fluorescent lamp having a CRI approximately the same as the CRI of the lamp phosphor is disclosed. The method includes applying a coating comprising fine particle-size silica to the inner surface of the lamp envelope to form a coated envelope, the coating having a coating weight greater than 0.7 milligrams per square centimeter and less than the weight at which lumen output of the lamp is reduced due to absorption of visible wavelength light by the silica. A coating of phosphor selected to provide a predetermined CRI is applied over the silica layer; and the coated phosphor envelope is processed into a finished lamp. A fluorescent lamp having a CRI approximately equal to the CRI of the lamp phosphor is also disclosed. The lamp of the present invention includes a lamp envelope having an inner surface; a layer of fine particle-size silica disposed on the inner surface of the lamp envelope, the silica layer containing greater than about 0.7 mg/cm.sup.

Abstract: A fluorescent lamp discharge tube has an electrostatically coated envelope. The coating comprises a mixture of 100 parts by weight of phosphor, 0.01 to 3 parts by weight of a fatty acid having a melting point greater than 40.degree. C. or the ammonium, aluminum alkaline earth salts thereof, and 0.05 to 5 parts by weight of finely divided aluminum oxide having a grain size smaller than 0.1 micron. The phosphor is applied to the tube by a venturi effect and results in a more uniformly applied coating than is provided using a suspension coating. Uniformity of the coating is measured by the disclosed optical densitometry test.

Abstract: A method of manufacturing a low-pressure mercury vapor discharge lamp with a discharge vessel comprising two or more substantially parallel co-extending glass discharge tube portions (4 and 5) interconnected through a coupling which extend transversely to the wall of said tube portions. First, the inner wall of an elongate tube is provided with a luminescent material. Then, while heating at least a short zone of the wall, the elongate tube is then divided into two portions. End walls are formed during the division on which the luminescent layer extends the thickness of the tube wall and the temperature of the heated zone are chosen so that no particles of the luminescent material are enclosed in the glass of the end wall during said dividing process and fracture is avoided at least after cooling.At least at the area of the transition from the end wall to the tube wall, the ratio AB/CD is 0.4 to 0.8.

Abstract: A method for preventing the hydration/solubilization of the protective oxide coating of a phosphor is described. The method involves coating of the oxide coated phosphor particles with a continuous hydrophobic coating. After the phosphor particles are coated with the continuous hydrophobic coating and the continuous hydrophobic coating cured, they are added to a water-based suspension and subsequently processed into a lamp.

Abstract: A fluorescent lamp including a glass envelope having first and second end caps at the opposite ends thereof and each end cap provided with a connecting pin, the glass envelope containing energization means for generating light emanating from the lamp and upon energization thereof a first portion of the glass envelope adjacent the first end cap and a second portion of the glass envelope adjacent the second end cap being heated to a first temperature and an intermediate glass portion intermediate the first and second glass portions being heated to a second temperature lower than the first temperature, and a composite safety coating including first and second substantially light transparent coatings and an intermediate substantially light transparent coating intermediate the first and second coatings, the first coating surrounding and secured to the first glass portion and including an outer end portion surrounding and secured to a portion of the first end cap not including the first connecting pin and including

Abstract: A method for eliminating carbonaceous contaminants and preventing the hydration/solubilization of the oxide coating of a phosphor is described. The method involves the annealing of the oxide coated phosphor at a temperature and for a period sufficient to preclude adversely affecting the protective oxide coating on the phosphor during subsequent water-based suspension processing without detrimentally altering the phosphor. After annealing the phosphor is cooled and then added to a water-based suspension. The optimum conditions for annealing a manganese activated zinc silicate phosphor or a calcium halophosphate phosphor having a protective aluminum oxide coating are the combination of a temperature between about 700.degree. C. and about 850.degree. C. and for a period of time from about 15 minutes to about 20 hours.

Abstract: A process for the preparation of a radiation image storage panel which comprises a support, a light-reflecting layer and a stimulable phosphor layer, superposed in this order, characterized in that applying a binder solution-I containing a light-reflecting material and a binder solution-II containing a stimulable phosphor onto a surface of a support or a sheet in such a manner that both the binder solutions are superposed, to form a light-reflecting layer and a stimulable phosphor layer simultaneously.

Abstract: Making method for a phosphor layer of a small diameter cathode ray tube comprises application of a centrifugal force of above 100G in a direction parallel to the axis of a glass bulb toward its bottom panel to become a face plate, thereby forcedly making sedimentation of phosphor powder onto the inner surface of the bottom panel, and thus, by adoptation of the centrifugal force, a phosphor layer of very fine and dense configuration and uniform thickness is obtainable even using such small medium grain size of phosphor powder of under 4 .mu.m.

Abstract: The use of radiant energy and a radiation curable adhesive to bond components to glass where direct irradiation proves impossible is disclosed. The process utilizes the light scattering properties of glass to convey radiant light energy along an axis generally perpendicular to the incident radiant light resulting in cure of adhesive in shadow areas. The process finds particular utility in the bonding of light opaque end caps to fluorescent tubes.

Abstract: A phosphor particle having a non-particulate, conformal aluminum oxide coating and a fluorescent lamp incorporating aluminum oxide coated phosphor particles are disclosed. A method for improving the lumen maintenance of a fluorescent lamp is also disclosed. The method involves applying a non-particulate, conformal aluminum oxide coating to the outer surface of individual particles of a finely-divided fluorescent lamp phosphor, applying the coated phosphor particles to a fluorescent lamp envelope, and processing the phosphor coated envelope into a finished lamp.

Abstract: Lumen maintenance and spectral output of fluorescent lamps is improved by applying over the phosphor a vapor deposited film consisting of yttrium oxide and at least one activator. The vapor is generated by electron beam bombardment of the activated yttrium oxide target and the film is most efficacious when applied to a thickness of from about 0.2 microns to about 1.5 microns.

Abstract: The luminescent material(s) optionally composed of more color components are suspended in the solution of active agent(s) and treated with 0.5 to 10% by weight of glass forming acid or a mixture thereof, preferably boric acid or phosphoric acid calculated on the weight of the luminescent material. Then a solution comprising 1 to 15% by weight of aliphatic amines calculated on the weight of the luminescent materials is added and the mixture thus obtained is homogenized.

Abstract: Method and apparatus for electrostatically applying phosphor coatings to the interior surface of fluorescent lamp tubes includes equipment for applying an electrical charge of one polarity to the glass wall and electrical charge of the opposite polarity to the phosphor particles to cause the phosphor particles to adhere to the glass surface until the particles can be heated to bond them to the interior surface of the glass by lehring. By using electrostatic deposition the lehring may be done at a lower temperature than is required with conventional phosphor deposition using organic binders so that U-shaped fluorescent lamps do not experience distortion from the lehring temperature. The invention includes the fluorescent lamps provided which are devoid of residue of organic binder.

Abstract: A method of forming a luminescent layer on a glass carrier (such as the wall of a discharge vessel of a low-pressure mercury vapor discharge lamp) from a suspension of grains of a luminescent material and a quantity of binder in a suspension medium. According to the invention, the suspension medium preferably consists of water and the binder mainly comprises fibrous crystals of boehmite.