WO2013070672A1 - Procédé et dispositif pour fabriquer un ruban de verre - Google Patents

Procédé et dispositif pour fabriquer un ruban de verre Download PDF

Info

Publication number
WO2013070672A1
WO2013070672A1 PCT/US2012/063819 US2012063819W WO2013070672A1 WO 2013070672 A1 WO2013070672 A1 WO 2013070672A1 US 2012063819 W US2012063819 W US 2012063819W WO 2013070672 A1 WO2013070672 A1 WO 2013070672A1
Authority
WO
WIPO (PCT)
Prior art keywords
glass
glass ribbon
furnace
ribbon
preform
Prior art date
Application number
PCT/US2012/063819
Other languages
English (en)
Inventor
Sean Matthew Garner
Joseph M. Matusick
David John Mcenroe
Original Assignee
Corning Incorporated
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Corning Incorporated filed Critical Corning Incorporated
Priority to JP2014541172A priority Critical patent/JP6280503B2/ja
Priority to KR1020147014869A priority patent/KR101979048B1/ko
Priority to CN201280065946.5A priority patent/CN104185611B/zh
Publication of WO2013070672A1 publication Critical patent/WO2013070672A1/fr

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B23/00—Re-forming shaped glass
    • C03B23/02—Re-forming glass sheets
    • C03B23/037—Re-forming glass sheets by drawing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B17/00—Layered products essentially comprising sheet glass, or glass, slag, or like fibres
    • B32B17/06—Layered products essentially comprising sheet glass, or glass, slag, or like fibres comprising glass as the main or only constituent of a layer, next to another layer of a specific material
    • B32B17/10—Layered products essentially comprising sheet glass, or glass, slag, or like fibres comprising glass as the main or only constituent of a layer, next to another layer of a specific material of synthetic resin
    • 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
    • C03C17/00—Surface treatment of glass, not in the form of fibres or filaments, by coating
    • C03C17/28—Surface treatment of glass, not in the form of fibres or filaments, by coating with organic material
    • C03C17/32—Surface treatment of glass, not in the form of fibres or filaments, by coating with organic material with synthetic or natural resins
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B19/00—Other methods of shaping glass
    • C03B19/02—Other methods of shaping glass by casting molten glass, e.g. injection moulding
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B19/00—Other methods of shaping glass
    • C03B19/12—Other methods of shaping glass by liquid-phase reaction processes
    • C—CHEMISTRY; METALLURGY
    • C03—GLASS; MINERAL OR SLAG WOOL
    • C03B—MANUFACTURE, SHAPING, OR SUPPLEMENTARY PROCESSES
    • C03B19/00—Other methods of shaping glass
    • C03B19/14—Other methods of shaping glass by gas- or vapour- phase reaction processes
    • 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
    • C03C2218/00—Methods for coating glass
    • C03C2218/30—Aspects of methods for coating glass not covered above
    • C03C2218/355—Temporary coating
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P40/00—Technologies relating to the processing of minerals
    • Y02P40/50—Glass production, e.g. reusing waste heat during processing or shaping
    • Y02P40/57—Improving the yield, e-g- reduction of reject rates

Definitions

  • the invention relates generally to a method and an apparatus for forming glass ribbon, and more particularly to drawing a flat, thin glass ribbon from a glass preform.
  • a stream of molten glass-forming material is discharged from a melting furnace into a float furnace that contains a liquid metal medium.
  • the metal is tin.
  • the atmosphere in the float furnace is controlled to prevent oxidation of the tin.
  • the molten glass floats and spreads out on the liquid tin in the form of a flat, continuous ribbon.
  • the ribbon of glass is conveyed into an annealing lehr or cooling tunnel, where it is cooled at a controlled rate to ambient temperature.
  • the cooled glass has a flat, smooth surface that may, in some instances, require further finishing by processes such as grinding and polishing.
  • a glass-forming melt flows into a refractory trough and then overflows in a controlled manner from either side of the trough.
  • a key advantage of this process is that the surface of the glass ribbon that is ultimately formed does not come in contact with any refractory material or other forming equipment.
  • Another benefit of the process is that it yields a very flat and uniformly thick ribbon of glass. As a result, no secondary processing is needed to obtain a smooth, flat, and uniform ribbon of glass for display applications.
  • the method suffers from not being able to process glasses having high strain points due to the high temperatures required, since such temperatures greatly accelerate deterioration of the glass forming components, and there is potential for increased contamination of the glass melt.
  • roll-to-roll refers to the supply of a glass ribbon from a first, or source roll to a second or take-up roll, wherein processing of the ribbon occurs as the glass ribbon travels from the source roll to the take-up roll.
  • Current processes for fabricating thin glass sheet such as slot draw, fusion forming and float, have limitations in producing thin glass ribbons, such as glass ribbons having a thickness as thin or thinner than about 200 ⁇ , for example 50 to 100 micron. Redraw or down drawing a glass sheet preform enables the fabrication of glass ribbon having a thickness less than 100 ⁇ with good geometrical and strength attributes.
  • a glass ribbon having no warp, wrinkle or other visible distortion, excluding the very edges of the ribbon can be achieved by controlling the viscosity of the drawn glass and maintaining a specific thermal profile within the draw furnace. This can be expanded by employing a second furnace that thermally conditions the drawn shape. Distortion can be further reduced by applying a low draw tension to the glass ribbon.
  • the drawn glass ribbon may be applied with a protective coating to maintain its strength attribute and enables the glass ribbon to be spooled.
  • a method for making a glass ribbon comprising heating a glass preform in a draw furnace to form a glass ribbon, the glass preform comprising a central portion, a pair of opposing edge portions and a thickness of the glass preform is greater than 200 ⁇ , but preferably less than 1.5 mm, the heating comprising heating the glass preform such that a temperature of the central portion of the glass ribbon is greater than a temperature of the edge portions of the glass ribbon within a visco-elastic region of the glass ribbon.
  • the glass ribbon is drawn to a predetermined thickness such that a central portion of the glass ribbon is less than 200 ⁇ and thermally treated in a thermal conditioning furnace at a temperature greater than an annealing temperature of the glass ribbon but less than a softening point of the glass ribbon.
  • a first coating may be applied to the glass ribbon, after which the glass ribbon may be wound onto a take-up spool, wherein a bend radius of the wound glass ribbon is less than about 10 cm.
  • the draw furnace may comprise edge heating elements positioned orthogonal to side heating elements.
  • the method may further comprise heating the glass preform in a preheat furnace prior to the heating in the draw furnace.
  • Drawing the glass ribbon preferably comprises contacting the glass ribbon with a tractor assembly that draws the glass ribbon downward between two counter-rotating belts.
  • a central portion of the glass ribbon has a thickness less than about 200 ⁇ . Edge portions of the glass ribbon may also be less than 200 ⁇ .
  • a strain point of the glass preform is preferably greater than about 600°C, and in some embodiments the strain point is greater than about 900°C.
  • a protective coating may be applied to the glass ribbon before the contacting by the tractor assembly such that the coating is positioned between the glass ribbon and the counter- rotating belts.
  • the protective coating may be applied as a solid film sourced from a roll of coating material that is unwound from the source roll and applied to the glass ribbon. Once formed, the glass ribbon may be rolled onto a spool.
  • an apparatus for drawing glass ribbon comprising a draw furnace configured to heat a solid glass preform, the draw furnace comprising a first plurality of heating elements arrayed horizontally along a direction of a width of the draw furnace and a second plurality of heating elements arrayed horizontally in a direction orthogonal to the width of the draw furnace.
  • the apparatus may further comprise a thermal conditioning furnace comprising a plurality of heating elements arrayed vertically along a length of the thermal conditioning furnace.
  • a thermal conditioning furnace comprising a plurality of heating elements arrayed vertically along a length of the thermal conditioning furnace.
  • the apparatus preferably comprises a first coating applicator for applying a film material between the glass ribbon and the counter-rotating belts.
  • the apparatus comprises a second coating applicator positioned downstream of the counter- rotating belts
  • the first plurality of heating elements are preferably separately controlled (i.e. a temperature of the heating elements is separately controlled.
  • the second plurality of heating elements may also be separately controlled.
  • the apparatus may further comprise a preheating furnace positioned upstream of the draw furnace.
  • FIG. 1 is a side cross sectional view of an apparatus for redrawing glass sheets into thinner glass sheets
  • FIG. 2 is a lateral cross sectional view of a draw furnace, including optional preheating furnace and a thermal conditioning furnace, used in the apparatus of FIG. 1 ;
  • FIG. 3 is a top down cross sectional view of a draw furnace of FIG. 2 showing horizontally arrayed heating elements that comprise separately-controlled heating zones;
  • FIG. 4 is a perspective view of an individual heating element for the draw furnace of FIG. 2;
  • FIG. 5 is a top down cross sectional view of a thermal conditioning furnace of FIG. 2 comprising vertically arrayed heating elements that comprise separately-controlled heating zones.
  • Embodiments of the present invention comprise, inter alia, providing a glass preform, heating the glass preform in a furnace, forming a gob and drawing the preform into a glass ribbon.
  • a gob what is meant is heating a glass preform to at least its softening point, whereupon a thickened portion of the preform, the gob, pulls away from the body of the preform, drawing with it a broad flow of glass.
  • the softening point is generally regarded as the temperature at which glass will deform under its own weight, a viscosity of approximately 10 7'6 poise.
  • a glass preform is formed by conventional glass forming techniques.
  • Such techniques include chemical vapor deposition and casting methods, including the use of sol gels.
  • Chemical vapor deposition (CVD) techniques are well known in the optical fiber arts, and include outside vapor deposition (OVD), vapor phase deposition (VAD), and modified chemical vapor deposition (MCVD), to name a few. Both OVD and VAD entail hydrolyzing glass precursor chemicals in a flame to form a soot, and depositing the soot onto a target to form a porous glass soot preform.
  • the porous soot preform may then be cleaned, dehydrated and consolidated by first heating the preform in the presence of a cleansing gas, such as a chlorine-containing gas, after which the preform is further heated to a temperature sufficient to cause the soot particles to consolidate into a clear, solid glass preform.
  • a cleansing gas such as a chlorine-containing gas
  • casting of a glass preform may include the mixing of organic glass precursors to form a greenware preform.
  • the greenware preform is dried by heating and/or exposure to a suitable cleansing gas such as a chlorine-containing gas, then heated to consolidate the greenware preform into a clear, solid glass preform.
  • a suitable cleansing gas such as a chlorine-containing gas
  • Alternative methods of casting a glass preform include melting glass (e.g. cullet or glass soot) in a suitable crucible and thereafter pouring the molten glass into an appropriate mold to form the desired preform shape. Both casting methods are well known in the art, and will not be described further. As with the methods of depositing glass described previously, it should be noted that casting methods are not limited to the examples presented herein.
  • a glass preform can be formed by other conventional glass forming techniques such as the previously described fusion or float process. Again, such processes are well known and will not be described further.
  • FIG. 1 shows an exemplary apparatus, generally designated by reference numeral 10, for drawing glass ribbon 12 from a glass preform 14 in accordance with an embodiment of the present invention.
  • Glass preform 14 is a glass sheet, seen edge-on in FIG. 1.
  • Glass preform 14 may be greater than 200 ⁇ , such as greater than 0.5 mm, greater than 0.7 mm, greater than 1.0 mm or greater than 1.2 mm. However, glass preform 14 is typically, though required to be, less than 1.5 mm.
  • Apparatus 10 comprises a downfeed assembly 16 for holding and moving glass preform 14, a draw furnace 18, an optional thermal conditioning furnace 20, an optional preheat furnace 22, a first coating applicator 24, a tractor 26, an optional second coating applicator 28, and a take-up spooling device 30.
  • apparatus 10 is capable of producing thin glass ribbons from a preform in an about 3 : 1 ratio according to a width of the preform. That is, due to necking- down of the glass ribbon as it is drawn from the glass preform, the glass ribbon typically has a total width that is approximately one third the total width of the glass preform, comprising edge portions and a central portion disposed therebetween.
  • Glass preform 14 may be provided by any of the techniques described above, or by any other known glass making techniques.
  • glass preform 14 is rectangular in shape, having generally parallel opposing sides and a width that is greater than the thickness.
  • the glass of the preform is preferable substantially transparent at visible wavelengths, having a transmittance of at least about 95% over the wavelength range from about 390 nm to about 750 nm.
  • the preform may be shaped, such as by grinding, into a generally rectangular shape.
  • glass ribbon 12 may be drawn from glass preforms having a strain point similar to conventional glasses used in float or fusion processes, e.g.
  • glass having much higher strain points such as strain points greater than about 700°C, 800°C or even greater than about 900°C, may be drawn.
  • pure fused silica having a strain point of about 1956°C may be drawn into a glass ribbon using the apparatus and methods of the present invention.
  • Glass preform 14 is typically suspended from preform downfeed assembly 16, which comprises clamp 32 for clamping onto and securely holding glass preform 14.
  • Downfeed assembly 16 is capable of moving the glass preform in parallel vertical directions, either upward or downward (along z axis 34), via motor 36 coupled to screw 38 by a nut (not shown).
  • the X, Y and Z axes represent three orthogonal axes.
  • Other suitable drive arrangements as may be known in the art capable of providing precise control of downfeed speed may, however, be substituted.
  • Downfeed assembly 16 is also capable of moving the preform in a direction orthogonal to the z axis (i.e. in the x-y plane) so that the glass preform may be positioned appropriately within draw furnace 18.
  • glass preform 14 is preferably centered within the draw furnace to ensure even heating of the preform.
  • glass preform 14 is lowered into a hot zone of draw furnace 18 by the downfeed assembly, whereupon a lower portion of glass preform 14 is heated to at least its softening point.
  • the draw furnace may be heated to a temperature of at least about 1075°C to "gob" the preform.
  • gobbing allows the glass to attenuate its width under its own weight and is done at slightly higher temperature than the actually drawing operation temperature.
  • Draw furnace 18 may be a resistance furnace, wherein heat is derived by flowing a current through resistance heating elements; an induction furnace, wherein heat is derived by inducing a current flow in a microwave susceptor; or any other heating method capable of heating the furnace to a temperature of at least the softening point of the glass preform.
  • the furnace could be a gas furnace wherein a gas fuel is burned to form a flame.
  • the furnace is capable of heating the glass to a temperature of at least about 900°C; more preferably at least about 1500°C; and most preferably to at least about 2200°C.
  • Draw furnace 18 is of the resistance type comprising a pair of opposing side plates 42 and a pair of opposing end plates 44 arranged in a rectangular shape defining a hollow interior space 46.
  • Draw furnace 18 comprises multiple horizontally-arrayed heating zones, labeled Zones 2 - 5 in FIG. 2, each heating zone comprising one or more heating elements 48 arranged laterally along the two major sides of the glass ribbon.
  • the heating elements of each heating zone are controlled independently from the heating elements of other heating zones, and in some embodiments, independently of other heating elements within the same heating zone.
  • Each heating element 48 is preferably shaped as a bar to ensure sufficient current carrying capacity, and may be formed from, for example, moly-disilicide.
  • side plates 42 and end plates 44 may be formed from a suitable high temperature heat conducting material such as silicon carbide (e.g. Hexoloy®) and are positioned between the glass preform and the heating elements.
  • the side plates diffuse the heat provided by the heating elements and provide a more even thermal profile within draw furnace 18 at each heating zone.
  • the end plates 44 of the rectangular draw furnace are of similar construction to side plates 42 and are heated as separate heating zones (labeled as zone 6 in FIG. 3) from zones 2 - 5.
  • Separate heating elements 50 within the end zones (zone 6) provide the ability to draw the sheet edge at a different viscosity than the center section of the glass ribbon by heating the edges of the glass ribbon to a different temperature than the center section of the glass ribbon.
  • End heating elements 50 may be of the same design as side heating elements 48 but arranged in an orientation generally orthogonal to the orientation of side heating elements 48, and positioned to heat the edges of the glass ribbon rather than the lateral (major) surfaces of the glass ribbon.
  • the edges of the glass preform are heated to a temperature greater than an interior, central portion of the glass preform.
  • End plates 44 separate end heating elements 50 from glass ribbon 12. Side plates 42 and end plates 44 mitigate warp and other flatness distortions the drawn glass ribbon may experience due to thermal variation and applied drawing stress across the preform.
  • the preform root refers to the point where the glass preform transitions from an elastic solid to a viscous liquid, generally characterized by a width reduction. More simply put, the root denotes the region where the glass preform ends and the glass ribbon begins.
  • the ability to have temperature control between the glass preform center and the preform edges, particularly at the preform root, enables drawing of glass ribbon that is flat and substantially free of warp. However, the glass ribbon may exhibit some slight thickness variation on the extreme edges. Consequently, removal of the edge portions may be needed.
  • individual side heating elements 48 may be arranged linearly across the width of the furnace, i.e. in a single row.
  • the individual heating elements 48 are separately controlled, for example by a controller (not shown) such that a temperature of the individual heating elements may be separately adjusted.
  • a controller not shown
  • the use of individual heating elements, the temperature of which are separately controllable, provides greater flexibility to the drawing process by facilitating the application of a specific spatial temperature profile to the glass preform, and particularly to the glass ribbon across a width of the glass ribbon, thereby reducing temperature related defects such as warping of the glass ribbon due to an uneven temperature profile across the width of the ribbon.
  • the controller may also control the temperature of the individual heating elements to adjust a temperature profile that is applied to the glass preform.
  • each draw furnace heating element 48 and 50 may be formed as a "U" shaped element that extends in a longitudinal direction L consistent with the longitudinal direction of draw furnace 18. That is, preferably at least a portion of each individual heating element 48 and/or 50 extends vertically along a length of the draw furnace in a draw direction.
  • Thermocouples 52 may be inserted into draw furnace 18 at locations suitable for monitoring temperatures within the draw furnace.
  • a preheat furnace 22 may be positioned above draw furnace 18.
  • Draw furnace 18 may be idled at about 500°C between drawing cycles to extend the life of the draw furnace heating elements and to reduce the time needed to heat the furnace to the draw temperature. Immersing the glass preform into a draw furnace at 500°C is generally not a problem if the thermal expansion of the glass is sufficiently low. However, for high CTE glasses, or if the glass is an ion-exchangeable glass, care must be taken when loading the glass preform into the draw furnace.
  • optional preheat furnace 22 may be used to preheat the glass preform to a suitable temperature prior to glass preform 14 entering draw furnace 18.
  • Preheat furnace 22 comprises one or more heating elements 53 arranged across a width of preheat furnace 22, which heating elements may be resistive heating elements.
  • heating elements 53 may be wire heating elements, such as coiled wire heating elements.
  • a suitable heating element material may comprise tungsten or nichrome.
  • Apparatus 10 may comprise an optional thermal conditioning furnace 20, an embodiment of which is shown in FIGS. 2 and 5, that may be positioned underneath draw furnace 18 relative to a draw direction.
  • thermal conditioning furnace 20 has multiple heating zones arrayed vertically along the conditioning furnace in direction L, the multiple heating zones comprising a plurality of heating elements 54 arranged vertically down the length of the conditioning furnace.
  • Thermal conditioning furnace 20 typically has a reduced temperature capability compared to draw furnace 18, and may, for example, be fitted with resistance wire heating elements 54. That is, heating elements 54 preferably have less current carrying capability than draw furnace heating elements 48 and/or 50.
  • Thermal conditioning furnace 20 is preferably rectangular in shape with independently controlled side and end heating elements. It should be noted that thermal conditioning furnace 20 is not an anneal furnace since temperatures in the upper heating zones of the thermal conditioning furnace are intended to be operated above the anneal point of the glass ribbon.
  • Thermal conditioning furnace 20 is used to control the shape of the glass ribbon to reduce distortions in the glass ribbon. In addition, thermal conditioning furnace 20 helps reduce some of the internal stress induced into the glass ribbon by quenching the glass ribbon. Thermal conditioning furnace 20 may be directly coupled to draw furnace 18, as shown in FIG. 1, or thermal conditioning furnace 20 may be separate and spaced apart from draw furnace 18.
  • thermal conditioning furnace 20 preferably includes heat dissipating plates 39 positioned along a width of the thermal conditioning furnace between the heating elements and the drawn glass ribbon.
  • Thermal conditioning furnace may also include heat dissipating plates 41 positioned between the end heating elements and the edges of the glass ribbon.
  • Heat dissipating plates 19 and 23 may be formed from Hexoloy® or similar material.
  • thermal conditioning furnace 20 under the redraw furnace further enables the ability to draw flat glass ribbon.
  • the top zone in the conditioning furnace is at a temperature just below the softening point of the glass but above the anneal point of the glass, it is still hot enough to allow viscoelastic deformation of the glass.
  • the edges of the drawn glass ribbon are cooling faster than the center region as the ribbon traverses through the upper zones of the thermal conditioning furnace. With the draw tractor applying a draw tension uniformly across the more ridged portions of the glass ribbon (not to be confused with the lower viscosity region of the preform as mentioned above) the glass will flatten out as the edges quench.
  • the center zone of the conditioning furnace is at a temperature greater than the anneal temperature of the glass of the glass ribbon and the lower zone is at a temperature at approximately the strain point of the glass. This allows any residual stress in the glass ribbon to be reduced or eliminated since the glass ribbon is so thin that the time during which the ribbon is within these zones is sufficient. This, in turn, enables the glass to be spooled without breakage and subsequently used in a roll-to-roll process.
  • a polymer coating 56 is preferably applied to the ribbon above draw tractor 26.
  • Coating 56 protects the glass ribbon from contact with downstream draw components to maintain an acceptable optical quality of the surface and prevent surface damage to the glass that may reduce the strength of the glass ribbon.
  • a system to apply a tape to the ribbon edges may be performed during drawing.
  • the taped edges of the glass ribbon can enable roll-to-roll processing from the spool by providing a location where the ribbon can be handled. That is, the roll-to-roll handling equipment is able to grip the tape with a mechanical delivery system.
  • the edge taping application may be performed off-line if the polymer coating is to be removed before the tape is applied.
  • the equipment and process is capable of applying full or partial- width protective coatings to the glass ribbon surface, and the coatings can be permanently or temporarily bonded to the glass.
  • FIG. 1 shows a first coating applicator 24 for applying protective polymer coating 56 to glass ribbon 12.
  • Protective polymer coating 56 may be supplied from at least one supply roll 58 and applied to glass ribbon 12 by an applicator 60.
  • applicator 60 may comprise rollers for pressing a coating film to the glass ribbon.
  • the applied protective polymer coating 56 is applied to both major surfaces of the glass ribbon.
  • Protective polymer coating 56 provides mechanical protection to the quality area of glass ribbon 12 and prevents direct contact between the glass ribbon and tractor 26.
  • the term quality area refers to that portion of the glass ribbon that is eventually sold and used in the manufacture, in direct comparison with the edge portions of the glass ribbon that are typically removed from the glass ribbon and may be used as cullet in further glass forming processes. Thus, the quality area is the central portion of the glass ribbon.
  • the glass preform is lowered at a precise feed rate into the furnace dictated by the downfeed motor speed and the temperature profile established within draw furnace 18. For example, a typical downfeed rate for the glass preform is on the order of 10 to 12 mm/min. As previously noted, the draw furnace is lowered to a suitable draw temperature from the starting gobbing temperature (e.g.
  • the main parameter drivers for the redraw process are: the downfeed rate, the furnace temperature that controls the viscosity of the glass and the pull rate, also known as the draw speed.
  • the draw viscosity is normally in the range between about 10 6 poise to about 10 7 poise.
  • a suitable draw tension as measured by a load cell located in the downfeed system, satisfactory draw tension can be in the range from about 2 to 3 pounds.
  • a difficulty in drawing a sheet-shaped glass ribbon from a glass preform is that the preform may have, for example, a thickness of about 0.70 mm thick but about 300 mm wide, which equates to an approximately 1 :400 aspect ratio or greater.
  • to maintain an appropriate flatness of the drawn ribbon requires careful monitoring of the glass preform downfeed rate, the draw furnace temperature and the draw rate applied by tractor 26.
  • a polymeric coating may be applied, for example, by drawing the glass ribbon through a liquid coating bath.
  • a liquid coating may be sprayed onto the surface of the glass.
  • the liquid coating may be applied to one or more surfaces of the glass.
  • the liquid coating may thereafter be cured by a suitable curing apparatus as is required for the coating type.
  • the curing apparatus may be an oven for coating which is cured by heating (thermal cure), or the curing apparatus may cure the coating by exposing the coating to ultraviolet light (photocure).
  • the coatings or coatings applied to the glass ribbon can be permanently or temporarily bonded to the glass.
  • Draw tractor 26 comprises two counter-rotating belts 62 driven by a plurality of drive wheels 64 such that the motion between them is downward.
  • Counter-rotating belts 62 are movable inward, toward the glass ribbon, or outward, away from the glass ribbon.
  • glass ribbon 12 is pinched between the belts.
  • the belts may be opened and closed by pneumatically driven actuators, and the pinch force applied by the belts when closed can be adjusted.
  • the pinch force is maintained at a minimal amount so as not to crush the glass ribbon between the belts, but enough to allow the belts to open and close smoothly.
  • the tractor unit speed is servo-controlled and set to a speed sufficient to maintain a slight tension on the glass ribbon.
  • a load cell on the clamping device (not shown) provides measurement feedback to the controller so that draw tension applied to the preform can be controlled.
  • a typical draw speed or pull rate is about 0.30 m/min.
  • Belts 62 draw glass ribbon 12 downward from glass preform 14.
  • Belts 62 are preferably formed from a high temperature-resistant resilient material. It has been found that a softer, more resilient belt performs better than a hard belt surface.
  • belts 62 extend across the entire width of the glass ribbon, and may, for example, be wider than the glass ribbon.
  • a coating as previously described may be positioned between the glass ribbon and the belts, such as by applying the coating to the glass ribbon, to protect the major surfaces of the glass ribbon from direct contact with the belts.
  • tractor 26 may comprises a plurality of narrow belts that can be independently vertically positioned and wherein each belt can be run open or closed.
  • each belt can be run open or closed.
  • six belts may be used, where three belts are positioned on one side of the glass ribbon and the other three belts are positioned on the other side of the glass ribbon.
  • This tractor system enables drawing the glass ribbon from only its edges or only the center or a combination of these.
  • Such an arrangement of tractor belts allows the application of a substantially uniform drawing force to be exerted across a much wider ribbon, e.g. glass ribbons having widths up to 500 mm.
  • the previously described "single" tractor is limited to ribbon widths less than about 150 mm.
  • the glass ribbon thickness attenuates until the central portion of the glass ribbon reaches a predetermined thickness. That is, the ribbon will typically include a central portion and thickened edge portions. The edge portions may be removed, wherein the central portions can be further processed.
  • the thickness of the glass ribbon, and particularly a thickness of the central portion is a factor of, inter alia, the speed at which the ribbon is drawn from the preform, the speed at which the preform is fed into draw furnace 18 (the downfeed rate), and the temperature of the draw furnace.
  • the upper limit for the thickness of a glass ribbon that may be drawn is generally determined by the thickness of the preform.
  • the maximum thickness of the drawn glass ribbon is less than about 1.5 mm, less than about 1.0 mm, and more preferably less than about 0.7 mm, but typically greater than 200 ⁇ .
  • Glass ribbon drawn in accordance with embodiments of the present invention may be drawn such that a thickness of the central portion of the ribbon is equal to or less than about 200 ⁇ , equal to or less than about 150 ⁇ , equal to or less than about 100 ⁇ , or equal to or less than about 50 ⁇ .
  • a thickness of the edge portions of the glass ribbon may also be drawn to be less than 200 ⁇ .
  • the thickness of the glass ribbon may be measured as part of the drawing process, and the result of such a measurement may be used to control, for example, the downfeed rate of the preform and/or the draw rate of tractor 26.
  • the glass ribbon thickness may be measured by a suitable measuring device, such as a laser micrometer, indicated by reference numeral 66 in FIG. 1. Such devices are commercially readily available.
  • An error signal is developed by measuring device 66 based on a predetermined set point for glass ribbon thickness which has been input into a controller.
  • the error signal is relayed to the controller (not shown).
  • the controller may be, for example, a computer.
  • the controller may then adjust downfeed rate, edge roller rotational speed and/or torque, or furnace temperature, or a combination thereof according to pre-determined instructions (such as a computer program), to reduce the error signal from measuring device 66 and therefore correct the glass ribbon thickness.
  • an optional second coating applicator 28 may be employed. As shown in FIG. 1, second coating applicator assembly 28 for applying protective film 68 to glass ribbon 12 may be included. Protective film is supplied from at least one supply roll 70 and applied to glass ribbon 12 by an applicator roll 72. Preferably, the applied protective film 68 is applied to both major surfaces of the glass ribbon.
  • the final step is spooling the coated ribbon.
  • the manner of recovering the drawn glass ribbon from the drawing operation depends in part upon the thickness of the glass ribbon, and more particularly to the thickened edge portions. For example, if the glass ribbon thickened edge portions have a thickness equal to or less than about several hundreds of microns, the glass ribbon may be rolled onto bulk spool 31, shown in FIG. 1, using a motorized spooler.
  • the spooler has a tension control that allows the glass to be wrapped securely onto the spool with minimal tension.
  • the spools could be stored for long periods of time and from bending the glass around the spool diameter a surface tension is induced on the ribbon therefore having a lower spooling tension on the glass will reduce breakage.
  • Bulk spool 31 may then be used as a source spool in a subsequent roll-to-roll process wherein the glass ribbon is moved from the source spool to a subsequent take-up spool and intermediate processing occurs to the glass ribbon as it travels from the source spool to the take-up spool.
  • the intermediate processing can include, for example, finishing (e.g. removal) of the glass ribbon edges, deposition of one or more thin film layers, or any other process than may be used to add value to the glass ribbon in the furtherance of providing a finished product.
  • finishing e.g. removal
  • several spools of ribbon can be spliced together to provide longer lengths of ribbon.
  • individual panels of predetermined size may be cut from the ribbon at a later time if desired.
  • Glass ribbon having a thickness such that the glass ribbon would break during an attempt to roll the ribbon, for example greater than about a millimeter in thickness, must be cut into individual panels of a predetermined size or sizes during the drawing process. Cutting of the glass ribbon into individual panels may be accomplished by any conventional method known in the art, including scoring and breaking, or laser cutting of the glass ribbon.
  • the draw furnace and the thermal conditioning furnace are segregated into zones, wherein temperatures within the zones can be individually manipulated.
  • an exemplary temperature profile for drawing a glass ribbon from a glass sheet preform can be established so that the zones for the draw and thermal conditioning furnaces are heated in accordance with Table 1.
  • the glass preform according to the present example may have a width in a range from about 280 mm to about 325 mm.
  • the length of the glass sheet is consistent with the amount of glass intended to be drawn and the physical capability of the draw apparatus.
  • the glass preform has a strain point in a range from about 600°C to about 1956°C, for example, from about 600°C to about 1000°C, from about 600°C to about 900°C or from about 600°C to about 800°C.
  • the glass preform has a strain point in a range from about 700°C to about 1956°C, from about 800°C to about 1956°C, from about 900°C to about 1956°C or from about 1000°C to about 1956°C.
  • a thickness of the preform may be in a range, for example, from about 0.70 to about 1.5 mm.
  • the glass preform is driven downward by downfeed assembly 16 at a feed rate in a range from about 10 mm/min to about 12 mm/min.
  • a draw speed applied by tractor assembly 26 is in a range from about 0.2 to about 0.4 meters/min.
  • the draw speed applied by tractor 26 may be about 0.3 meters/min, resulting in a draw tension at the centerline of the glass ribbon of about 2.8 pounds.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Organic Chemistry (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Geochemistry & Mineralogy (AREA)
  • Re-Forming, After-Treatment, Cutting And Transporting Of Glass Products (AREA)

Abstract

La présente invention porte sur un procédé pour fabriquer des rubans plats d'un matériau à base de verre et sur un appareil pour celui-ci. Le procédé met en œuvre la fourniture d'une préforme de verre, le chauffage de la préforme de verre dans un four, la formation d'une paraison et d'un pré-ruban, le retrait de la paraison et l'étirage du pré-ruban de verre sous la forme d'un ruban de verre plat. L'invention porte également sur un appareil pour étirer une préforme de verre sous la forme d'un ruban de verre, lequel appareil comprend un four d'étirage, des bras d'étirage pour étirer et tirer le pré-ruban sous la forme d'un ruban de verre, et des rouleaux de bord opposés pour appliquer une force vers le bas sur le ruban de verre. Le four d'étirage peut comprendre une pluralité d'éléments chauffants individuels, la température de chaque élément chauffant étant apte à être commandée de façon séparée. L'appareil peut de plus comprendre un four de recuit pour recuire le ruban de verre.
PCT/US2012/063819 2011-11-09 2012-11-07 Procédé et dispositif pour fabriquer un ruban de verre WO2013070672A1 (fr)

Priority Applications (3)

Application Number Priority Date Filing Date Title
JP2014541172A JP6280503B2 (ja) 2011-11-09 2012-11-07 ガラスリボンを形成するプロセス及び装置
KR1020147014869A KR101979048B1 (ko) 2011-11-09 2012-11-07 유리 리본을 제조하는 공정 및 장치
CN201280065946.5A CN104185611B (zh) 2011-11-09 2012-11-07 制造玻璃带的方法和装置

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201161557521P 2011-11-09 2011-11-09
US61/557,521 2011-11-09

Publications (1)

Publication Number Publication Date
WO2013070672A1 true WO2013070672A1 (fr) 2013-05-16

Family

ID=48290493

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2012/063819 WO2013070672A1 (fr) 2011-11-09 2012-11-07 Procédé et dispositif pour fabriquer un ruban de verre

Country Status (5)

Country Link
JP (1) JP6280503B2 (fr)
KR (1) KR101979048B1 (fr)
CN (1) CN104185611B (fr)
TW (1) TWI583637B (fr)
WO (1) WO2013070672A1 (fr)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20140357467A1 (en) 2013-06-04 2014-12-04 Schott Ag Method for redrawing of glass
CN104261658A (zh) * 2014-09-24 2015-01-07 河北省沙河玻璃技术研究院 一种用于二次熔融法拉制柔性玻璃的加热炉
JP2015182909A (ja) * 2014-03-24 2015-10-22 Hoya株式会社 ガラスプリフォームの製造装置、ガラスプリフォームの製造方法、及び、光学素子の製造方法
JP2016044090A (ja) * 2014-08-21 2016-04-04 日本電気硝子株式会社 ガラス牽引装置、ガラス成形装置及びガラス成形方法
US9682883B2 (en) 2013-04-30 2017-06-20 Schott Ag Method for production of glass components
EP3180188A4 (fr) * 2014-08-15 2018-08-22 3M Innovative Properties Company Assemblages de films de polymère et de verre et leurs procédés de fabrication
CN112334419A (zh) * 2018-06-28 2021-02-05 康宁公司 制造玻璃带的连续方法和由其所拉制的玻璃制品
US11078102B2 (en) * 2014-11-26 2021-08-03 Corning Incorporated Thin glass sheet and system and method for forming the same
CN113943111A (zh) * 2014-01-29 2022-01-18 康宁股份有限公司 可弯折玻璃堆叠组件、制品及其制造方法
CN115710084A (zh) * 2022-11-03 2023-02-24 长飞光纤光缆股份有限公司 一种玻璃板定向拉伸装置及拉伸方法
US11912605B2 (en) 2018-06-28 2024-02-27 Corning Incorporated Glass articles
WO2024044089A1 (fr) * 2022-08-25 2024-02-29 Corning Incorporated Système et procédé de moulage continu de structures en verre composite monocouche ou multicouche

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20200026316A (ko) * 2017-07-28 2020-03-10 코닝 인코포레이티드 유리 가공 장치 및 방법들
CN107522399A (zh) * 2017-09-18 2017-12-29 张家港伟宇工艺玻璃制品有限公司 一种高性能工艺玻璃的制作工艺
WO2021050506A1 (fr) * 2019-09-13 2021-03-18 Corning Incorporated Procédés continus de formation d'un ruban de verre à l'aide d'un dispositif de chauffage à micro-ondes du type gyrotron
WO2021050651A1 (fr) * 2019-09-13 2021-03-18 Corning Incorporated Systèmes et procédés permettant le formage d'un ruban de verre à l'aide d'un dispositif de chauffage

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3996035A (en) * 1975-10-01 1976-12-07 Ppg Industries, Inc. Coating and heat strengthening glass sheets
US4240816A (en) * 1979-02-09 1980-12-23 Mcmaster Harold Method and apparatus for forming tempered sheet glass with a pyrolytic film in a continuous process
US6815070B1 (en) * 1999-04-30 2004-11-09 Schott Spezialglas Gmbh Polymer-coated thin glass film substrates
US20070209398A1 (en) * 2004-07-29 2007-09-13 Cimo Patrick J Process and device for manufacturing glass sheet

Family Cites Families (17)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3635687A (en) * 1970-05-26 1972-01-18 Owens Illinois Inc Downdrawing method for producing very thin glass sheets
JPS595530B2 (ja) * 1976-01-12 1984-02-06 日本電気硝子株式会社 硝子元板を引き延ばして薄板を製造する方法及び装置
JPS594383B2 (ja) * 1977-08-06 1984-01-30 日本電気硝子株式会社 ガラス薄板の製造方法
JPS6033770B2 (ja) * 1977-12-20 1985-08-05 旭硝子株式会社 薄板ガラスの成形装置
JPS5895622A (ja) * 1981-12-01 1983-06-07 Nippon Electric Glass Co Ltd ガラス薄板製造方法
JPH0729796B2 (ja) * 1989-10-26 1995-04-05 日本電気硝子株式会社 ガラス製品の製造装置
JPH05116974A (ja) * 1991-09-03 1993-05-14 Alps Electric Co Ltd ガラス薄板の製造方法および製造装置
JP3475974B2 (ja) * 1994-12-28 2003-12-10 日本電気硝子株式会社 ガラス薄板の製造装置
JP3692511B2 (ja) * 1995-09-26 2005-09-07 日本電気硝子株式会社 結晶性ガラスの延伸成形方法
JP2000203857A (ja) * 1999-01-08 2000-07-25 Nippon Sheet Glass Co Ltd ガラススペ―サの製造方法
KR100524842B1 (ko) * 2002-09-25 2005-10-28 삼성코닝정밀유리 주식회사 낮은 잔류응력을 갖는 평판 유리의 제조방법
JP4914001B2 (ja) * 2004-11-29 2012-04-11 キヤノン株式会社 延伸ガラス部材の製造方法、画像表示装置用スペーサの製造方法および画像表示装置の製造方法
JP4886452B2 (ja) * 2006-09-25 2012-02-29 キヤノン株式会社 延伸ガラス部材の製造方法、画像表示装置用スペーサの製造方法及び画像表示装置の製造方法
JP2009126725A (ja) * 2007-11-20 2009-06-11 Canon Inc ガラス部材の製造方法及び加熱延伸装置
KR20120046734A (ko) * 2009-08-07 2012-05-10 아사히 가라스 가부시키가이샤 초박판 유리 기판의 제조 방법
JP2011144093A (ja) * 2010-01-18 2011-07-28 Nippon Electric Glass Co Ltd 板状ガラスの製造方法及びその装置
JP5652742B2 (ja) * 2010-02-12 2015-01-14 日本電気硝子株式会社 強化板ガラス及びその製造方法

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3996035A (en) * 1975-10-01 1976-12-07 Ppg Industries, Inc. Coating and heat strengthening glass sheets
US4240816A (en) * 1979-02-09 1980-12-23 Mcmaster Harold Method and apparatus for forming tempered sheet glass with a pyrolytic film in a continuous process
US6815070B1 (en) * 1999-04-30 2004-11-09 Schott Spezialglas Gmbh Polymer-coated thin glass film substrates
US20070209398A1 (en) * 2004-07-29 2007-09-13 Cimo Patrick J Process and device for manufacturing glass sheet

Cited By (20)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9682883B2 (en) 2013-04-30 2017-06-20 Schott Ag Method for production of glass components
US10611662B2 (en) 2013-04-30 2020-04-07 Schott Ag Method for the production of glass components
US20140357467A1 (en) 2013-06-04 2014-12-04 Schott Ag Method for redrawing of glass
JP2015006981A (ja) * 2013-06-04 2015-01-15 ショット・アーゲー ガラスのリドロー加工方法
US10259737B2 (en) 2013-06-04 2019-04-16 Schott Ag Method for redrawing of glass
US10384973B2 (en) 2013-06-04 2019-08-20 Schott Ag Method for redrawing of glass
CN113943111B (zh) * 2014-01-29 2023-09-15 康宁股份有限公司 可弯折玻璃堆叠组件、制品及其制造方法
US11745471B2 (en) 2014-01-29 2023-09-05 Corning Incorporated Bendable glass stack assemblies, articles and methods of making the same
CN113943111A (zh) * 2014-01-29 2022-01-18 康宁股份有限公司 可弯折玻璃堆叠组件、制品及其制造方法
JP2015182909A (ja) * 2014-03-24 2015-10-22 Hoya株式会社 ガラスプリフォームの製造装置、ガラスプリフォームの製造方法、及び、光学素子の製造方法
US10688768B2 (en) 2014-08-15 2020-06-23 3M Innovative Properties Company Glass and polymer film assemblies and methods of making
EP3180188A4 (fr) * 2014-08-15 2018-08-22 3M Innovative Properties Company Assemblages de films de polymère et de verre et leurs procédés de fabrication
JP2016044090A (ja) * 2014-08-21 2016-04-04 日本電気硝子株式会社 ガラス牽引装置、ガラス成形装置及びガラス成形方法
CN104261658A (zh) * 2014-09-24 2015-01-07 河北省沙河玻璃技术研究院 一种用于二次熔融法拉制柔性玻璃的加热炉
US11078102B2 (en) * 2014-11-26 2021-08-03 Corning Incorporated Thin glass sheet and system and method for forming the same
CN112334419A (zh) * 2018-06-28 2021-02-05 康宁公司 制造玻璃带的连续方法和由其所拉制的玻璃制品
CN112334419B (zh) * 2018-06-28 2023-05-12 康宁公司 制造玻璃带的连续方法和由其所拉制的玻璃制品
US11912605B2 (en) 2018-06-28 2024-02-27 Corning Incorporated Glass articles
WO2024044089A1 (fr) * 2022-08-25 2024-02-29 Corning Incorporated Système et procédé de moulage continu de structures en verre composite monocouche ou multicouche
CN115710084A (zh) * 2022-11-03 2023-02-24 长飞光纤光缆股份有限公司 一种玻璃板定向拉伸装置及拉伸方法

Also Published As

Publication number Publication date
TWI583637B (zh) 2017-05-21
JP2015502315A (ja) 2015-01-22
KR20140107225A (ko) 2014-09-04
CN104185611A (zh) 2014-12-03
CN104185611B (zh) 2018-02-06
KR101979048B1 (ko) 2019-05-15
TW201328991A (zh) 2013-07-16
JP6280503B2 (ja) 2018-02-14

Similar Documents

Publication Publication Date Title
KR101979048B1 (ko) 유리 리본을 제조하는 공정 및 장치
JP2015502315A5 (fr)
JP4982366B2 (ja) ガラスシートの製造方法および製造装置
JP4845034B2 (ja) ガラス条の製造方法
KR101679353B1 (ko) 유리 리본 및 그 제조 방법
EP3224209B1 (fr) Feuille de verre mince et son système et procédé de formation
JP5733639B2 (ja) ガラス基板
US8062733B2 (en) Roll-to-roll glass material attributes and fingerprint
JP5595479B2 (ja) ガラスセラミック物品並びにガラスをセラミック化するための方法及び装置
US20080280057A1 (en) Process and apparatus for making glass sheet
KR101845575B1 (ko) 유리판 성형품의 제조 방법 및 유리판 성형품의 제조 장치
JP5241223B2 (ja) ガラス板の製造方法及び製造設備
KR101651326B1 (ko) 유리의 재인발 방법
JP4302367B2 (ja) 光ファイバの線引き方法および線引き装置
WO2022091657A1 (fr) Procédé de production d'une feuille de verre, feuille de verre, dispositif et équipement de production de feuille de verre
JP2012167014A (ja) ガラス板の製造方法及び製造設備
JP2004074572A (ja) フィルム熱処理装置

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 12846883

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2014541172

Country of ref document: JP

Kind code of ref document: A

NENP Non-entry into the national phase

Ref country code: DE

ENP Entry into the national phase

Ref document number: 20147014869

Country of ref document: KR

Kind code of ref document: A

122 Ep: pct application non-entry in european phase

Ref document number: 12846883

Country of ref document: EP

Kind code of ref document: A1