Classifications

• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B37/00—Joining burned ceramic articles with other burned ceramic articles or other articles by heating
  • C04B37/04—Joining burned ceramic articles with other burned ceramic articles or other articles by heating with articles made from glass
  • C04B37/045—Joining burned ceramic articles with other burned ceramic articles or other articles by heating with articles made from glass characterised by the interlayer used
• • C—CHEMISTRY; METALLURGY
  • C03—GLASS; MINERAL OR SLAG WOOL
  • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
  • C03C27/00—Joining pieces of glass to pieces of other inorganic material; Joining glass to glass other than by fusing
  • C03C27/06—Joining glass to glass by processes other than fusing
• • C—CHEMISTRY; METALLURGY
  • C03—GLASS; MINERAL OR SLAG WOOL
  • C03C—CHEMICAL COMPOSITION OF GLASSES, GLAZES OR VITREOUS ENAMELS; SURFACE TREATMENT OF GLASS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS, MINERALS OR SLAGS; JOINING GLASS TO GLASS OR OTHER MATERIALS
  • C03C8/00—Enamels; Glazes; Fusion seal compositions being frit compositions having non-frit additions
  • C03C8/14—Glass frit mixtures having non-frit additions, e.g. opacifiers, colorants, mill-additions
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
  • H01J29/00—Details of cathode-ray tubes or of electron-beam tubes of the types covered by group H01J31/00
  • H01J29/02—Electrodes; Screens; Mounting, supporting, spacing or insulating thereof
• • H—ELECTRICITY
  • H01—ELECTRIC ELEMENTS
  • H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
  • H01J9/00—Apparatus or processes specially adapted for the manufacture, installation, removal, maintenance of electric discharge tubes, discharge lamps, or parts thereof; Recovery of material from discharge tubes or lamps
  • H01J9/24—Manufacture or joining of vessels, leading-in conductors or bases
  • H01J9/26—Sealing together parts of vessels
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
  • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
  • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
  • C04B2235/32—Metal oxides, mixed metal oxides, or oxide-forming salts thereof, e.g. carbonates, nitrates, (oxy)hydroxides, chlorides
  • C04B2235/3289—Noble metal oxides
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
  • C04B2235/02—Composition of constituents of the starting material or of secondary phases of the final product
  • C04B2235/30—Constituents and secondary phases not being of a fibrous nature
  • C04B2235/36—Glass starting materials for making ceramics, e.g. silica glass
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
  • C04B2235/65—Aspects relating to heat treatments of ceramic bodies such as green ceramics or pre-sintered ceramics, e.g. burning, sintering or melting processes
  • C04B2235/658—Atmosphere during thermal treatment
  • C04B2235/6581—Total pressure below 1 atmosphere, e.g. vacuum
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B2235/00—Aspects relating to ceramic starting mixtures or sintered ceramic products
  • C04B2235/70—Aspects relating to sintered or melt-casted ceramic products
  • C04B2235/96—Properties of ceramic products, e.g. mechanical properties such as strength, toughness, wear resistance
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
  • C04B2237/02—Aspects relating to interlayers, e.g. used to join ceramic articles with other articles by heating
  • C04B2237/10—Glass interlayers, e.g. frit or flux
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
  • C04B2237/50—Processing aspects relating to ceramic laminates or to the joining of ceramic articles with other articles by heating
  • C04B2237/70—Forming laminates or joined articles comprising layers of a specific, unusual thickness
  • C04B2237/708—Forming laminates or joined articles comprising layers of a specific, unusual thickness of one or more of the interlayers
• • C—CHEMISTRY; METALLURGY
  • C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
  • C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
  • C04B2237/00—Aspects relating to ceramic laminates or to joining of ceramic articles with other articles by heating
  • C04B2237/50—Processing aspects relating to ceramic laminates or to the joining of ceramic articles with other articles by heating
  • C04B2237/80—Joining the largest surface of one substrate with a smaller surface of the other substrate, e.g. butt joining or forming a T-joint

Definitions

• the invention relates to a junction material between at least one spacer based on ceramic or glass, and a glass substrate.
• Spacers are used which are fixed to a glass substrate in the production, for example, of emissive flat screens, such as field emission screens (EDFs), composed of two substrates between which a space of limited thickness is maintained by means of said spacers. spacers.
• EDFs field emission screens
• An FED screen has a cathode and an anode formed by two plane glass substrates facing each other.
• elements emitting electrons such as for example metallic microtips or carbon nanotubes
• on the anode are notably deposited phosphor materials emitting light corresponding to the colors green, red and blue.
• Electrons are extracted from the cathode by means of an extraction voltage applied between the cathode and electrodes called "electrode spoilers" arranged on the same substrate. These electrons emitted from the cathode are then accelerated by the electric field generated by the application of a voltage between the anode and the cathode. They reach the phosphors of the anode which excited, emit their color and generate an image.
• a well defined space typically 0.1 to 5 mm separates the two substrates sealed between them, this space in which the vacuum prevails being called gap. Due to the vacuum between the two substrates, the pressure difference with the outside creates a force which tends to crush the substrates. Also, in order to resist atmospheric pressure so that the screen does not implode, spacers are arranged between the two substrates, that are the spacers, which make it possible to maintain a distance between the two glass substrates.
• spacers secured to at least one glass substrate is of course not limited to this application of FED screens, and other uses for which it is also necessary to maintain a constant spacing between two substrates, can be envisaged such as for example plasma screens, flat lamps, double vacuum glazing or even thermochromic glazing.
• the expression flat lamps should be understood to include lamps which may have a curvature on at least part of their surface, regardless of the technology of these lamps.
• spacers In general, the use which is made of these spacers serves to constitute spacers, parts of separation between two substrates.
• the attachment of spacers to a glass substrate can be achieved in different ways.
• one end of the spacer is coated with a metallic material by known deposition techniques, of the vacuum deposition type, and the substrate is also covered. of a metal coating by known techniques, of the type also vacuum deposition.
• the metallic materials used are preferably gold, but can also be chosen from aluminum, copper or nickel.
• the spacers covered with metal are applied against the metallized substrate, and a heat source such as a laser is directed on the assembly in order to ensure a welding of the two metallized elements.
• US Patent 5,561,343 proposes another solution, ultrasonic bonding.
• This document shows that one end of the spacers is provided with a metal comprising gold or aluminum capable of undergoing ultrasonic welding, and the substrate comprises metallized zones against which the ends of the spacers are intended to be applied. spacers.
• the weld is obtained using ultrasound delivered by a suitable device.
• emissive screens in particular for FED screens, for which charge exchanges take place between the cathode and the anode in order to activate the phosphors, it may appear on the surface of the spacers of the charges which may to influence parasitically on phosphors adjacent to those activated and which we do not wish to activate. Furthermore, for this type of application of emissive screens, it is advisable to provide means of bonding and possibly a method of bonding which ensure perfect positioning of the spacers so that they ensure lasting mechanical strength, without implosion of the screen.
• the positioning of the spacers at the desired location in the plane of the substrate and in a direction perfectly perpendicular to the plane of the substrate, and repeatedly for all of the spacers over the entire substrate is also important when s 'is to manufacture a screen for which the phosphors are arranged after and according to the arrangement of said spacers.
• the invention therefore aims to provide securing means which do not cause the drawbacks mentioned, and which can ensure adequate positioning of the spacers as well as ensuring the discharge function of the charges appearing on the surface of the spacers in order to '' prevent the creation of parasitic charges which would inadvertently activate the phosphors.
• the invention achieves this by means of a joining material which is characterized in that it comprises an enamel mixed with at least one metal oxide in the form of particles.
• the metal oxide is stable over time and in temperature up to at most 600 ° C. It contains one or more of the following: Zr, V, AI, Cr, Mn, Fe, Ca, Si, Co, Ni, Zn, Ti, Ni, Nb, W, Sb, Pb, Sn, Cu, Ru, Ir
• it is ruthenium oxide.
• the material has a resistivity between 10 5 and 10 10 ⁇ .cm.
• the material comprises at least one solvent and some resin. And advantageously, the material has at room temperature a viscosity at most equal to 50 Pa.s.
• the material of the invention makes it possible to produce a structure comprising two glass substrates kept apart with the aid of spacers, the spacers being secured at one of their ends with at least one substrate by virtue of said joining material.
• the opposite end of the spacers resting against the other substrate is coated with at least one bonding material which may comprise the junction material.
• the material junction can be a means adapted to bridge a height difference between a spacer end and a substrate.
• the spacers are conductive or non-conductive of electricity.
• the contact resistance of the junction material located between a spacer and a substrate is negligible compared to the resistance of the spacer.
• the method of securing spacers and a glass substrate using the material of the invention is characterized in that the spacers are held in a fixed position and are covered on one of their ends with the joining material, and the glass substrate is attached against said ends of the spacers covered with the junction material, the entire structure, substrate and spacers, then undergoing annealing.
• An annealing temperature is defined as a temperature at most equal to 600 ° C.
• the opposite end of the spacers assembled to the substrate as explained above will be covered with a bonding material and another substrate will be attached against said opposite ends of the spacers, the assembly of the two substrates and the spacers then undergoing a last annealing.
• the spacers coated with the joining material on one and / or the other of their ends are annealed before their association with the substrate.
• the material of the invention can be used in the manufacture of emissive screens, of the plasma or FED screen type, of flat lamps, of insulating glazing under vacuum, of thermochromic glazing.
• FIG. 1 illustrates the junction material between a substrate and spacers
• - Figure 2 illustrates the device for measuring the resistivity of the junction material
• Figure 3 shows the structure of Figure 1 with which another substrate is associated. The figures are not drawn to scale to facilitate understanding.
• FIG. 1 illustrates a substrate 10 on which spacers 20 are bonded using a joining material 30.
• the substrate 10 is made of glass, and has a planar surface on the bonding side of the spacers.
• the spacers 20 are based on glass or ceramic, they are conductive or non-conductive of electricity, and can have various shapes, the section of which can be in particular circular, rectangular or in the shape of a cross.
• the joining material 30 comprises an enamel mixed with at least one electrically conductive element, in particular a metal oxide in the form of particles.
• the enamel is glass-based, the composition of which is chosen from the sealing frit compositions usually used in the glass industry. Sealing involves heating to a temperature not exceeding 600 ° C. For use in an emissive screen, the sealing temperature is preferably between 400 and 550 ° C. In other uses, for example for securing spacers as spacers for insulating glazing of the vacuum type, it may be lower temperatures of the order of 200 ° C. which thus allow avoid tempering of glazing and / or reduce the cost of sealing.
• the metal oxide particles ensure that the junction material is electrically conductive, so that the material can perform, in addition to its bonding role, a function for discharging electrical charges possibly contained on the surface of the spacers.
• the material must be sufficiently conductive to evacuate said electrical charges. Its electrical resistivity must however remain sufficiently high so as to avoid the parasitic emission effect.
• the parasitic emission is for example highlighted in a screen with emission of fields when only a voltage is applied between the cathode and the anode without providing an extraction voltage. Under these conditions, the cathode does not emit electrons. However, due to the electric field created by the voltage applied between the cathode and the anode, electrons are extracted from the conductive junction material and come to inadvertently excite the phosphors which constitutes a parasitic emission observed all around the spacer.
• the material has a resistivity p of between 10 5 ⁇ .cm and 10 10 ⁇ .cm. This value is given for a material which has already undergone various heat treatments which correspond to the treatments which the material would undergo during the manufacture of an FED type emissive screen.
• the resistivity is measured at room temperature on a sample of the material 30 having an area S, for example 1 cm 2 , and a thickness e, for example 15 ⁇ m.
• the sample is integral with two substrates 10 coated with a conductive layer 11 ( Figure 2) to form two electrodes between which a voltage is applied, all the substrates and the sample having undergone the heat treatments necessary for manufacturing an emissive screen.
• the current is measured to deduce therefrom a resistance value which, related to the thickness e and to the surface S of the sample, makes it possible to deduce the resistivity p.
• the metal oxide present in the form of particles in the joining material must have, after being annealed, the following properties: to be stable over time and in temperature, that is to say that the oxide does not does not dissolve in the enamel, and in particular in a range of temperatures for which the joint material withstands several anneals up to 600 ° C., in particular under vacuum, under air or under inert gas, in order to resist the process of sealing spacers on the substrate as well as the manufacturing process, for example of emissive screens, using a substrate of this type provided with spacers; - do not generate visible parasitic emission around the spacers.
• the metal oxide particles consist of one or more of the following elements which do not dissolve in the enamel at the temperatures described above, in particular up to 600 ° C: Zr, V, Al, Cr, Mn, Fe , Ca, Si, Co, Ni, Zn, Ti, Ni, Nb, W, Sb, Pb, Sn, Cu, Ru, Ir. Ruthenium oxide will be preferred for further its adequate resistivity.
• the junction material therefore also has properties adapted to the method of its deposition on the ends 21 of the spacers.
• the material must have a viscosity at room temperature of less than 50 Pa.s.
• Pine oil such as terpineol, can be used as solvent which allows viscosity to be controlled. The proportion of solvent used will affect the viscosity.
• This resin disappears after a first annealing.
• first step the sealing of a first substrate with the spacers is done in an open medium, and in a second step, the sealing is carried out in a closed environment, that is to say that said substrate provided with spacers is hermetically sealed with another element such as another substrate ( Figure 3).
• the joining material is deposited by any suitable means on the ends 21 of the spacers, the ends being maintained in a periodic network in the same plane; the substrate is then added against the spacers and an annealing operation at approximately 550 ° C. under vacuum of the assembly is carried out to ensure the consolidation of the bonding, the evacuation of the solvents and of the resin, possibly polluting, being carried out by all adapted means.
• the evacuation of solvents and resin is useful at this stage in an open environment because otherwise, if the entire structure for an FED screen was sealed in a single step and therefore in a closed environment, the solvents and the resin volatilized by heating the junction material could concentrate over time in the hermetic medium between the two substrates, which could pollute screen elements such as phosphors or electron emitting elements, degrading the performance of the screen.
• the deposition of the junction material on the spacers can for example be carried out by depositing a layer of the material on a plate of size at least substantially equivalent to the distribution surface of the spacers. While the spacers are held in position by a device with a multitude of clamps for example, the plate coated with the material is temporarily applied with a slight pressure if necessary against the ends of the spacers to obtain a deposit. As a variant, the spacers held in position are brought at their end in a glue bath to deposit.
• the material of the invention by its tackiness even before a first annealing makes it possible to ensure, when the substrate is associated with the spacers provided with the material, that the spacers are held in place without the risk of involuntarily moving them. Indeed, a positioning deviation could cause in the use of the substrate with spacers untimely functioning problems such as the unwanted activation of certain phosphors in an emissive screen.
• the adhesive is distributed homogeneously over the ends of the spacers, which makes it possible to obtain a balanced and homogeneous electrical conduction at the end of the spacers by which electrical charges are intended to be removed for application in an emissive screen.
• the field lines generated by the accumulation of charges in a place would generate the deflection of the electrons emitted by the cathode which would thus come to light phosphors which one does not wish to activate.
• another substrate 40 is attached against the other free end 22 of the spacers that have possibly been previously covered with a bonding material 50, such as the junction material of the invention for example, a means sealing (glass frit or material of the invention) being also arranged in the manner of a frame on the entire periphery of one of the substrates.
• a bonding material 50 such as the junction material of the invention for example, a means sealing (glass frit or material of the invention) being also arranged in the manner of a frame on the entire periphery of one of the substrates.
• an annealing will be carried out just after the deposition of the junction material against the ends of the spacers, and before the association of the substrate (s) with said spacers, so as to remove solvents and resin.
• the screen is sealed by at least one annealing at a temperature below 500 ° C for example, and simultaneously a vacuum is created inside the screen. In this way, the joint material softens and under the effect of atmospheric pressure acting against the outer faces of the screen, the joint material at the ends 21 and / or 22 of the spacers is crushed against the and / or the substrates, thus ensuring a better conductive bond.
• the inventors For optimal discharge of the charges, the inventors have shown that it is necessary for the contact resistance of the joint material located between a spacer and a substrate to be negligible compared to the resistance of the spacer.
• negligible means at least a factor of ten less.
• the inventors have shown that it is sufficient to measure the resistance of an entire structure composed of the spacers, the junction material and the substrates coated with a conductive layer to constitute electrodes and compare it to the total resistance of the spacers expected or calculated knowing their number, their geometry and the resistivity of the material or materials which constitute them.
• the resistance of the structure is deduced by applying a variable voltage between the two substrates of the structure and by measuring the current. When the measured resistance of the structure is substantially equivalent to the expected resistance of the spacers, the contact resistance is effectively considered to be negligible.
• spacers bonded with the junction material of the invention can be envisaged in any application requiring keeping a spacing between two substrates constant.
• the applications can be field emission screens, plasma screens, flat lamps, double vacuum glazing or thermochromic glazing.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Organic Chemistry (AREA)
• Materials Engineering (AREA)
• Ceramic Engineering (AREA)
• Geochemistry & Mineralogy (AREA)
• General Chemical & Material Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Life Sciences & Earth Sciences (AREA)
• Manufacturing & Machinery (AREA)
• Structural Engineering (AREA)
• Joining Of Glass To Other Materials (AREA)
• Manufacture Of Electron Tubes, Discharge Lamp Vessels, Lead-In Wires, And The Like (AREA)
• Vessels, Lead-In Wires, Accessory Apparatuses For Cathode-Ray Tubes (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=32319960

Family Applications (1)

Country Status (8)

Families Citing this family (7)

Family Cites Families (11)

• 2002
  • 2002-12-04 FR FR0215256A patent/FR2848333B1/fr not_active Expired - Fee Related
• 2003
  • 2003-11-19 JP JP2004564261A patent/JP2006508889A/ja active Pending
  • 2003-11-19 AU AU2003295029A patent/AU2003295029A1/en not_active Abandoned
  • 2003-11-19 KR KR1020057009814A patent/KR20050084063A/ko not_active Application Discontinuation
  • 2003-11-19 WO PCT/FR2003/003424 patent/WO2004060826A1/fr active Search and Examination
  • 2003-11-19 EP EP03786023A patent/EP1567461A1/de not_active Withdrawn
  • 2003-11-19 CN CNB2003801051763A patent/CN100354223C/zh not_active Expired - Fee Related
  • 2003-11-19 US US10/531,440 patent/US20050271837A1/en not_active Abandoned

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events