The application is required on the November 9th, 2011 of the U.S.Provisional Serial submitted according to 35.U.S.C. § 119The benefit of priority of No. 61/557521, its content is as foundation and to be included in a manner of herein.
The content of the invention
The ability for producing thin flexible glass substrate is that the roller of flexible electronic device and display is of interest to roller working process's.As it is used herein, roller to roller refers to supply to the glass tape of the second roller or takers-in from the first roller or source roller, whereinGlass tape from source roller advance to takers-in when, the working process of band occurs.Such as slot drawn, found the thin glass of manufacture with float glass processThe existing process of glass plate has the limitation for producing thin glass tape, such as with about 200 μm of equally thin or about 200 μm of ratiosThe glass tape of the thickness of thin (for example, 50 to 100 microns).Again draw or draw glass plate prefabrication downwards and make it possible to manufactureGlass tape with the thickness less than 100 and good geometry and Intensity attribute.Even if it is not new moulding process to draw againAnd have been used for fiber, tubing and other glasswares, but the ability for drawing flat glass band is that acquisition is sufficiently thin and soft enoughProperty substrate unique technical, the substrate can wind and for roller to roller technique.Roller to roller technique enables coating to pass through existing workIndustry technology is printed in thin substrate.For example, in roller into roller technique, thin film electronic can be deposited on movable glass band.
The glass tape of edge without band, non-distorted, wrinkle or other visible deformations can draw glass by controllingSpecified temp distribution in viscosity and holding tempering furnace.This second stove that shape can be drawn by using heat treatment extends.DeformationCan further it be reduced to glass tape by applying low tensile stress.Drawing glassribbons can scribble protective coating to keep its intensity categoryProperty simultaneously makes glass tape to wind.
Therefore, in one embodiment, a kind of method for manufacturing glass tape is disclosed, this method is included in tempering furnace and addedFor hot glass preform to form glass tape, glass preform includes core, a pair of opposing edge parts and glass preformThickness be more than 200 μm, but preferably less than 1.5mm, heating includes heating glass preform and caused in the viscoelastic region of glass tapeInterior, the temperature of the core of glass tape is higher than the temperature of the marginal portion of glass tape.Glass tape is drawn to predetermined thickness and causedThe core of glass tape in the annealing temperature higher than glass tape but is less than the soft of glass tape less than 200 μm and in heat-treatment furnaceIt is heat-treated at a temperature of changing point.First coating is coatable to arrive glass tape, and after this, glass tape can be wound up on take-up spool, itsThe bending radius of middle wound glass tape is less than about 10cm.
Tempering furnace may include to be positioned to and the orthogonal edge heating element of side heat element.Method is additionally included in backGlass preform is heated in preheating furnace before heating in stove.
Drawing glassribbons are preferably comprised glass tape and tractor component touch, and the traction device assembly is in two reversely rotationsTurn downward drawing glassribbons between conveyer belt.It is preferred that the core of glass tape has the thickness less than about 200 μm.GlassThe marginal portion of glass band is also smaller than 200 μm.
The strain point of glass preform is preferably higher than about 600 DEG C, and in certain embodiments, strain point is higher than about900℃。
Protective coating before the contact by drawing device assembly it is coatable to glass tape coating be located at glass tape andBetween reverse rotation conveyer belt.For example, protective coating can be used as being derived from the solid film of coating raw material volume, coating raw material can be from source rollerUntie and be coated to glass tape.Once being formed, glass tape can be rolled onto on spool.
In another embodiment, a kind of device of drawing glassribbons is described, the device includes being configured to heat solid-state glassThe tempering furnace of glass prefabrication, tempering furnace include along more than first horizontally disposed individual heating element heaters of the width of tempering furnace and along withMore than second horizontally disposed individual heating element heaters of the width mutually orthogonal direction of tempering furnace.
Device can also include heat-treatment furnace, and heat-treatment furnace includes the multiple heating units arranged vertically along the length of heat-treatment furnacePart.It is installed in rotation on below tempering furnace and is preferably configured as extending and retracting from glass tape relative to glass tape respectivelyReverse rotation conveyor belt design glass tape and apply downward power to glass tape into coordinating.Device, which is preferably comprised, to be used for filmMaterial is coated in glass tape and reversely rotates the first applying coating device between conveyer belt.In certain embodiments, device includesPositioned at the second applying coating device for reversely rotating conveyer belt downstream.
More than first individual heating element heaters (that is, the temperature for controlling heating element heater respectively) are preferably controlled respectively.Also can control respectivelyMake individual heating element heater more than second.
Device may also include the preheating furnace positioned at tempering furnace upstream.
Below in reference to accompanying drawing illustrative description during, it will the present invention is more readily understood, of the invention is otherPurpose, feature, details and advantage can also become more fully apparent, and the illustrative description is not intended to the limited making of taste anywayWith.
Embodiment
In the following detailed description, in order to illustrate rather than the purpose of limitation, showing for a variety of specific details will be illustratedExample embodiment is to be fully understood by the present invention.But one of ordinary skill in the art is being used for reference in disclosed hereinAfter appearance, it is readily apparent that can be put into practice without departing from the other embodiments of detail disclosed herein for themThe present invention.In addition, description of the omission to known devices, method and material is so that description of the invention understands.Finally, use as far as possibleIdentical reference indicates identical component.
Embodiments of the invention heat glass preform including offer glass preform, in stove, form tear drop and will be in advanceProduct is drawn into glass tape etc..Meant by forming tear drop and glass preform is heated at least its softening point, therefore in advanceThe change thickness portion (tear drop) of product leaves from preform body, is drawn into roomy flat glass stream.Softening point is generally recognizedTo be glass in its own weight, about 107.6The temperature that can be deformed under pool viscosity.
In one embodiment of the invention, glass preform is formed by traditional glass forming technique.These technology bagsChemical vapor deposition and die casting method are included, includes the use of sol-gel.Chemical vapor deposition (CVD) technology is in field fiberIt is well known, and including outside vapor deposition (OVD), vapour deposition (VAD) and improved chemical vapor deposition (MCVD) etc.Deng.OVD and VAD is required for degrading glass precursor chemicals in flame to form soot (soot), and by soot deposit to targetUpper formation cellular glass soot preform product.Heated by first in the case of the purgative gas that such as chlorine-containing gas be present prefabricatedProduct, after this prefabrication be further heated sufficiently to the temperature for causing soot particles to be solidified into bright solid glass prefabricationDegree, porous soot preform product can then be cleaned, dried and solidified.It is to be noted, however, that available glass deposition process is unlimitedIn example set forth above.
In contrast to OVD or VAD, the die casting of glass preform may include that mixing organic glass precursors are prefabricated to form green compactProduct.Green compact prefabrication by heating and/or dried exposed to the suitable purgative gas of such as chlorine-containing gas, be then heated to byGreen compact prefabrication is solidified into bright solid glass prefabrication.The alternative of molded glass prefabrication is included in suitable crucibleMelt glass (for example, cullet or glass soot) and melten glass is hereafter poured into appropriate mould to form required prefabricationShape.Two kinds of die casting methods are well known in the art and will not be described further.Such as with foregoing deposit glassMethod it is the same, it should be noted that die casting method be not limited to set forth herein example.
In other embodiments, glass preform can be founded or other traditional glasses of floating process as the aforementioned by allForming technique is formed.In addition, these techniques are well known and will not be described further.
Fig. 1 shows according to embodiments of the present invention to be used to generally use accompanying drawing by what glass preform 14 was drawn into glass tape 12The exemplary means that mark 10 indicates.Glass preform 14 is the preceding glass plate in the edge seen in Fig. 1.Glass preform14 can be more than 200 μm, for example more than 0.5mm, more than 0.7mm, more than 1.0mm or more than 1.2mm.However, glass preform 14Generally but require to be less than 1.5mm.Include being used to keep downward with movable glass prefabrication 14 according to the device 10 of the present embodimentComponent feeding 16, tempering furnace 18, optional heat-treatment furnace 20, optional preheating furnace 22, the first coater 24, tractor 26, canThe second coater 28 and Webbing take-up device 30 of choosing.Generally, device 10 can be according to the width of prefabrication with about 3:1 ratio is from pre-The thin glass tape of production of articles.That is, the necking down due to glass tape when it draws from glass preform, glass tape generally have aboutIt is 1/3rd beam overall of the beam overall of glass preform, during glass tape includes marginal portion and is arranged between marginal portionCenter portion point.
Glass preform 14 can provide by any one of above-mentioned technology or by other known glass manufacturing techniques.It is preferred that glass preform 14 is rectangular shape, there is almost parallel relative edge and the width more than thickness.The glass of prefabricationThe glass preferably substantially transparent under visible wavelength, have scope from about 390nm on about 750nm wavelength at least about95% light transmittance.The prefabrication formed for available such as cylindrical other shapes, prefabrication can be such as by grinding shapeInto rectangular shape.Although glass tape 12 can be from similar to the strain point for float glass process or the traditional glass of melting technologyThe glass preform of (for example, between about 600 DEG C and 700 DEG C) is drawn, but can draw the glass with much higher strain pointGlass, for example it is more than about 700 DEG C, 800 DEG C or even greater than about 900 DEG C of strain point.For example, with about 1956 DEG C shouldApparatus and method of the present invention can be used to be drawn into glass tape for the pure vitreous silica of height.
Glass preform 14 is typically hung under the downward component feeding 16 of prefabrication, and downward component feeding 16 includes being used forClip on glass preform 14 and firmly hold the clip 32 of glass preform 14.Downward component feeding 16 can be by by nut(not shown) is connected to the motor 36 of screw rod 38, and along parallel vertical direction, (along Z axis 34), movable glass is prefabricated up or downProduct.As it is used herein, X, Y and Z axis represent three orthogonal axis.But, using the teaching of the invention it is possible to provide to downward feed rateThe other suitable drives known in the art accurately controlled can be substituted for.Downward component feeding 16 can also along with Z axis phaseMutually the mobile prefabrication in vertical direction (that is, along X-Y plane) causes glass preform to be appropriately positioned in tempering furnace 18.ExampleSuch as, glass preform 14 is preferably located at the center in tempering furnace to ensure that prefabrication uniformly heats.
Once being suspended under downward component feeding 16, glass preform 14 lowers into tempering furnace by downward component feeding18 hot-zone, therefore the bottom of glass preform 14 is heated at least its softening point.For example, tempering furnace can be heated to it is at least bigAbout 1075 DEG C of temperature is so that prefabrication " tear drop ".The practice of tear drop allow glass make its width thinning under its own weight andCarried out at a temperature of a little higher than actual draw operation temperature.Tempering furnace 18 can be resistance furnace, wherein hot by by electric current streamStratie is crossed to obtain；Induction furnace, wherein it is hot by microwave susceptor induced current obtain；Or stove heat can be arrivedAt least other heating means of the temperature of the softening point of glass preform.For example, stove can be gas furnace, wherein gaseous fuel firesBurn to form flame.It is preferred that glass can be heated at least about 900 ° of temperature by stove；More preferably at least about 1500 DEG C；Most preferably arrive at least about 2200 DEG C.Once prefabrication is " tear drop ", so that it may reduces the temperature of tempering furnace.
In the embodiment of the tempering furnace 18 shown in Fig. 2, tempering furnace belongs to including being arranged to limit hollow interior space 46A pair of rectangular shape relative side plates 42 and a pair of relative end plates 44 resistance type.Tempering furnace 18 includes being labeled as in Fig. 2Multiple horizontally disposed heating zones in area 2-5, each heating zone include one along two primary side lateral arrangements of glass tapeIndividual or multiple heating element heaters 48.It is preferred that the heating element heater of each heating zone is controlled independently of the heating element heater of other heating zonesSystem, and in certain embodiments, controlled independently of other heating element heaters in identical heating zone.Each heating element heater 48 compared withBe goodly rod to ensure enough current capacities, and can be made up of such as molybdenum disilicide.In order to assist uniform thermal gradient of inductingWith reduce from the immediate glass preform of heating element heater caused by focus, side plate 42 and end plate 44 can be by such as diamond dust(for example,) suitable high-temperature heat-conductive material be made and be located between glass preform and heating element heater.Side plate spreadsThere is provided by heating element heater hot and interior in each heating zone offer more uniform temperature distribution in tempering furnace 18.Rectangle tempering furnaceEnd plate 44 has the construction similar to side plate and can heated as with 2-5 points of the area heating zone opened (area 6 is labeled as in Fig. 3).Independent heating element heater 50 in end region (area 6) provide by by the edge heating of glass tape to being different from glass tape coreTemperature with the viscosity different from glass tape core draw glass plate edge ability.End heat element 50 can haveThe direction arrangement for having with the design of the identical of side heat element 48 but being generally perpendicular to each other along the direction with side heat element 48,And it is positioned to heat its edges in addition to transverse direction (main) surface of glass tape.It is preferred that the edge of glass preformIt is heated to the inside more than glass preform, the temperature of core.End plate 44 is by end heat element 50 and glass tape 12Separate.Side plate 42 and end plate 44 relax what the drawing stress that drawing glassribbons apply due to thermal change and on prefabrication can be subjected toDistortion and other plane deformations.
Most of glass forming operation requires isothermy, but when drawing wide flat rubber belting again, it is preferred that have non-etc.Warm condition.Isothermy on glass preform can produce plus the pulling force for being applied to thinning glass tape on prefabrication widthNonuniform stretching tension force.Under isothermal conditions, tensile stress can be bigger than at edge at prefabrication center and therefore in prefabricationThe glass of the heart can draw soon than edge.On prefabrication width caused tensile stress difference can be produced in glass tape distortion andThickness change.For example, the curling in its edges may occur in which.By specifically in the glass preform edge heating of prefabrication rootThe influence of tensile stress is alleviated to the temperature higher than prefabrication center and produces more flat drawn ribbon.As it is used herein,Prefabrication root refers to that glass preform is converted to the point of viscous liquid from elastic solid (Hookean body), may be generally characterized as width reduction.MoreBriefly, root represents the region that glass preform terminates and glass tape starts.By temperature control at glass preform centerSpecifically the ability between the prefabrication edge of prefabrication root makes it possible to draw flat and substantially non-distorted glass tape.However, glass tape in extreme edge it is possible that some slight thickness changes.Accordingly, it may be desirable to remove edge partPoint.
In one embodiment, each side heat element 48 can be disposed linearly on the width of stove, i.e., in single file.Compared withGoodly, the temperature of each heating element heater is for example separately controlled by controller (not shown) and can be separated for each heating element heater 48Regulation.The use of each heating element heater, the temperature for each heating element heater that can be separately controlled are by promoting particular space temperature pointCloth is applied to glass preform and specifically to the glass tape on ribbon width, there is provided the flexibility bigger to drawing process,So as to reduce lacking for the temperature correlation for such as causing glass tape to distort due to the non-uniform temperature distribution on ribbon widthFall into.In the example using heating element heater multiple and being separately controlled, controller also can control the temperature of each heating element heater withRegulation is applied to the Temperature Distribution of glass preform.
As shown in figure 3, each tempering furnace heating element heater 48 and 50 can shape as along vertical with the vertical consistency of tempering furnace 18The " u "-shaped element extended to L.That is, it is preferred that length of at least a portion of each heating element heater 48 and/or 50 along tempering furnaceVertically extend along draw direction.Thermocouple 52 can insert tempering furnace 18 in the opening position suitable for monitoring tempering in-furnace temperature.
In addition to tempering furnace 18, as shown in figure 1, preheating furnace 22 can be positioned on the top of tempering furnace 18.Tempering furnace 18 is being drawnLeft unused between circulation at about 500 DEG C to extend the life-span of tempering furnace heating element heater and reduce stove heat to draw temperature instituteThe time needed.If the heat expansion of glass is sufficiently low, that tempering furnace that glass preform is immersed in into 500 DEG C is not usually problem.However, for high CTE glass, or if glass is chemcor glass, that is necessary when glass preform is loaded into tempering furnaceCarefully.In order to prevent the thermal shock to glass or tempering furnace part, optional preheating furnace 22 can be used for entering in glass preform 14Glass preform is preheating to suitable temperature before entering tempering furnace 18.Preheating furnace 22 includes one be arranged on the width of preheating furnace 22Individual or multiple heating element heaters 53, the heating element heater can be resistive heating elements.For example, heating element heater 53 can be such as lineThe wire heating element heater of round wire heating element heater.Suitable heating element material may include tungsten or nichrome.
Device 10 may include optional heat-treatment furnace 20, and the embodiment of heat-treatment furnace 20 is shown in Fig. 2 and Fig. 5, at heatReason stove 20 can be positioned on the lower section of tempering furnace 18 relative to draw direction.It is preferred that heat-treatment furnace 20 has along treatment furnace edge sideThe multiple heating zones arranged vertically to L, multiple heating zones include the multiple heating units arranged straight down along the length for the treatment of furnacePart 54.Heat-treatment furnace 20 generally has the temperature capability reduced compared with tempering furnace 18, and can for example be provided with resistance metal silkHeating element heater 54.That is, heating element heater 54 is preferably had than 48 and/or 50 small current capacity of tempering furnace heating element heater.At heatManage stove 20 and be preferably the side with independent control and the rectangular shape of end heat element.It should be noted that due to heat treatmentTemperature in the upper heating zone of stove is intended to operate on the annealing point of glass tape, therefore heat-treatment furnace 20 is not annealing furnace.HeatTreatment furnace 20 is used to control the shape of glass tape to reduce the deformation in glass tape.In addition, heat-treatment furnace 20 contribute to reduce byGlass tape quenching produces the part into the internal stress of glass tape.Heat-treatment furnace 20 can be directly coupled to tempering furnace 18, such asShown in Fig. 1, or heat-treatment furnace 20 can be separated and is spaced apart with tempering furnace 18.
Similar to tempering furnace 18, heat-treatment furnace 20 is preferably included between heating element heater and drawing glassribbons along heat treatmentThe heat sink 39 of the width positioning of stove.Heat-treatment furnace may also include the radiating between end heat element and its edgesPlate 41.Heat sink 39 and 41 can be byOr similar material is made.
Increase the ability that heat-treatment furnace 20 further provides for drawing flat glass band under draw machines again.In view of handlingLu Zhongshang areas are in just less than glass softening point but more than the temperature of glass annealing point, and treatment furnace still heat enough is to allow glassViscoelastic deformation.When glass tape crosses the upper area of heat-treatment furnace, the edge of drawing glassribbons is colder than center soon.WithDrawing tractor is equably on more carinate parts (not obscuring with the relatively low viscosity zone of above-mentioned prefabrication) of glass tapeApply tensile stress, glass can flatten when edge quenches.The center for the treatment of furnace is in the Annealing Temperature of Glass higher than glass tapeTemperature and lower area about strain point of glass temperature.Because glass tape is so thin so that glass tape is in these regionsTime is sufficient, and this allows any residual stress in glass tape to be reduced or eliminated.This enables glass is no to roll up damagedly againAround and be used subsequently to roller to roller technique.
After drawing process is stablized, polymer coating 56 is preferably coated with the glass on tractor 26 is drawnBand.Coating 56 prevents glass tape from being contacted with downstream drawing components with the acceptable optical quality of holding surface and prevents that glass can be reducedThe glass surface damage of glass band strength.In addition to applying coating, or applying coating is substituted, what it is by adhesive tape applicator to belt edge isSystem can be implemented in pulling process.The edge clung with adhesive tape of glass tape can handle the position of glass tape by providing, andRoller can be carried out from spool to roller working process.That is, roller to roller processing equipment can clamp adhesive tape by mechanical conveying system.OrIf polymer coating removes before adhesive tape application, that can implement the adhesive tape applicator at edge offline.Therefore, equipment and technique canThe protective coating of all or part of width is coated to ribbon surfaces, and coating can permanently or temporarily be bonded to glass.
Therefore, Fig. 1 shows the first coater 24 that polymer coating 56 will be protected to be coated to glass tape 12.Protect polymerCoating 56 can be supplied from least one donor rollers 58 and be coated to glass tape 12 by applicator 60.For example, applicator 60 can wrapInclude roller paint film being pressed onto on glass tape.It is preferred that the protection polymer coating 56 of coating is coated to two masters of glass tapeWant surface.Protection polymer coating 56 provides the mechanical protection to the high-quality area of glass tape 12 and prevents glass tape and tractor 26Between direct contact.As it is used herein, the high-quality area of term refers to and is generally removed from glass tape and can be used as entering oneThe marginal portion of the glass tape of cullet in step glass moulding processes directly contrasts, final to sell and for the glass tape of manufacturePart.Therefore, high-quality area is the core of glass tape.
Once drawing, glass preform is lowered into stove with accurate feed rate, and the feed rate is by downwardMotor speed and the interior Temperature Distribution established of tempering furnace 18 are fed to control.For example, the typical case of glass preform feeding downwardsSpeed about 10-12mm/min.As previously described, once tear drop is fallen and glass tape is attracted by tractor, tempering furnace is from openingBeginning tear drop temperature (for example, about 1075 DEG C) drops to suitable draw temperature.Again the major parameter of pulling process, which drives, is：ToLower feed rate, the furnace temperature and the also referred to as drawing speed of draw rate for controlling glass viscosity.Viscosity is drawn generally about 106Moor about 107Between pool.The suitable stretching such as measured by the dynamometer in downward feeder systemPower, gratifying tensile stress can be in the range of about 2 to 3 pounds.Flake glass band is drawn from glass preformDifficult point is that prefabrication can have the thick thickness of such as about 0.70mm but about 300mm is wide, and this is equivalent to about 1：400 height is wideThan or it is bigger.Therefore, in order to keep the suitable flat degree of drawing glassribbons, it is necessary to carefully monitor glass preform downward feedingSpeed, furnace temperature and the draw rate applied by tractor 26.
In alternative embodiments, polymer coating is for example applied by the way that glass tape is pulled through into liquid coating pond.Or liquidOn the sprayable surface to glass of coating.The coatable one or more surfaces to glass of liquid coating.Hereafter, liquid coating canSolidified by the suitable solidification equipment required by coating type.For example, solidification equipment can be for by being heating and curingThe oven (heat cure) or solidification equipment of coating can be by coating material solidified exposed to ultraviolet (photocuring) by coating.The coating orGlass can be permanently or temporarily bonded to by being coated to the coating of glass tape.
Once tear drop is dropped through and arrived under heat-treatment furnace 20, it is generally pulled through downwards coater with hand and is put into drawingDraw device assembly 26.Drawing tractor 26 includes two reverse rotation conveyer belts 62, reversely rotates conveyer belt 62 and passes through multiple drivesDriving wheel 64, which drives, make it that the motion between it is downward.Reversely rotating conveyer belt 62 can move inward to glass tape or away from glassGlass band is displaced outwardly.When conveyer belt is combined, glass tape 12 is clipped between conveyer belt.Conveyer belt can pass through pneumatic actuatorOpening and closing, and the grip force applied in closure by conveyer belt can adjust.For the thin glass tape with core, in thisCenter portion point with the thickness (such as average thickness) equal to or less than 200 μm, be for example equal to or less than about 150 μm, be equal to orLess than about 100 μm and in some instances equal to or less than about 50 μm, grip force is maintained at minimum and passed in order to avoid crushingThe glass tape between band is sent, but is enough to allow conveyer belt successfully to open and close.Tractor unit speed is servo-controlledAnd it is arranged to be enough to be maintained at the light tension on glass tape.Dynamometer on clamping device (not shown) provides measurement feedbackTo controller so that the tensile stress for being applied to prefabrication can control.Typical draw rate or drawing speed are about0.30m/min。
Conveyer belt 62 is from the downward drawing glassribbons 12 of glass preform 14.Conveyer belt 62 is preferably by high temperature resistant elastomeric materialIt is made.It has been found that softer, more flexible conveyer belt performance is better than hard transmission belt surface.It is preferred that conveyer belt 62 is in glassExtend on the whole width of band and can for example compare glass band width.Coating as the aforementioned is for example by can to glass tape by applying coatingIt is positioned between glass tape and conveyer belt to prevent the major surfaces of glass tape from being contacted with conveyer belt.
Or tractor 26 may include a plurality of narrow conveyer belt, a plurality of narrow conveyer belt can it is independently vertically oriented andWherein every conveyer belt can open or close.For example, six conveyer belts can be used, wherein three conveyer belts are positioned at glass tapeOther three conveyer belts are positioned on the opposite side of glass tape on side.The retractor system enables glass tape only from its edgeOr drawn only from center or from the combination of center and peripheral.This arrangement of tractor conveyer belt allows substantially uniform pulling forceIt is applied on much broader glass tape, such as the glass tape with the width for reaching 500mm.Foregoing " single " tractor is limited to widthGlass tape of the degree less than about 150mm.
When glass tape 12 is drawn downwards by tractor 26, ribbon thickness is thinning until the core of glass tape reachesTo predetermined thickness.That is, glass tape would generally include core and thickening marginal portion.Marginal portion can remove, wherein inCenter portion point can be processed further handling.The thickness of glass tape, and the especially thickness of core, it is that glass tape is drawn from prefabricationA factor in temperature of speed, the speed (downward feed rate) of prefabrication feeding tempering furnace and tempering furnace stretched etc..The upper thickness limit for the glass tape that can be drawn generally is determined by the thickness of prefabrication.It is preferred that the maximum gauge of drawing glassribbons is smallIn about 1.5mm, less than about 1.0mm and more preferably less than about 0.7mm, but typically larger than 200 μm.Implemented according to the present inventionThe glass tape that example is drawn can be drawn into cause the thickness of the core of glass tape equal to or less than about 200 μm, be equal to or smallIn about 150 μm, equal to or less than about 100 μm or equal to or less than about 50 μm.The thickness of the marginal portion of glass tapeIt can also be drawn into less than 200 μm.
The thickness of glass tape can be measured as a part for drawing process, and the measurement result can be used for control for example prefabricatedThe downward feed rate of product and/or the draw rate of tractor 26.Ribbon thickness can be measured by suitable measurement apparatus, exampleSuch as the laser micrometer for using reference 66 to indicate in Fig. 1.This device is commercially readily available.Error signal is according to defeatedThe ribbon thickness predetermined set-points for entering controller are produced by measurement apparatus 66.Error signal is delivered to controller and (not shownGo out).Controller can be for example computer.Controller can adjust feeding downwards then according to predetermined instruction (such as computer program)Speed, side roller velocity of rotation and/or torque or furnace temperature or its combination with reduce the error signal from measurement apparatus 66 and becauseThis correction ribbon thickness.
In certain embodiments, optional second coater 28 can be used.As shown in Figure 1, it may include for by diaphragm68 are coated to the second coating device assembly 28 of glass tape 12.Diaphragm can be supplied from least one donor rollers 70 and pass through coating roll72 are coated to glass tape 12.It is preferred that the diaphragm 68 of coating is coated to two major surfaces of glass tape.
Final step is the glass tape that winding coats coating.From draw operation recovery drawing glassribbons mode partly according toRely the thickness in glass tape, and more specifically thickening marginal portion.For example, if the thickened edges part of glass tape hasElectric coiling machine can be used to be wound up into the huge spool 31 shown in figure for thickness equal to or less than about hundreds of microns, that glass tapeOn.Up- coiler, which has, allows glass to be tightly wound up into the tension force on spool with minimum tension.Spool can store very long by oneThe section time, and because glass is bent around reel diameter, surface tension is produced on glass tape, therefore with relatively low on glassWinding tension can reduce breakage.Huge spool 31 can be then used as with the source book axle in back roller to roller technique, wherein glass tapeSubsequent take-up spool is moved to from source book axle and middle working process occurs when it advances to take-up spool from source book axle for glass tape.Middle working process may include such as finishing (for example, removal) its edges, one or more film layers of deposition or can be used forIncrease glass tape is worth to promote to provide other any techniques of finished product.For roller to roller working process, a few volume glass tapes can glueIt is connected together to provide greater length of glass tape.
Or if desired, can the time later from glass tape cutting predefined size each panel.With causingGlass tape is being drawn in the glass tape for attempting to wind the thickness (for example, thickness is more than about 1mm) that can be fractureed during glass tapeDuring cleavable each panel into preliminary dimension or size.Glass tape cuts into each panel can be by known in the artAny conventional method is completed, including glass tape delineation and fracture or be cut by laser.
Example
As described above, the fine-grained management of Temperature Distribution is that solve glass preform to be drawn into glass tape in glass preformWhen the tensile stress difference that is subjected to necessary to.Therefore, tempering furnace and heat-treatment furnace are divided into area, wherein the temperature in each area can divideDo not control.For example, referring to Fig. 2 and 3, can be created as from the exemplary temperature distribution of glass plate prefabrication drawing glassribbons so that returningEach area of stove and heat-treatment furnace is heated according to table 1.
Table 1
Scope can be had from about 280mm to about 325mm width according to the glass preform of this example.Glass plateLength is consistent with the amount of glass and the physical capability of drawing device for drawing.Glass preform has scope from about 600 DEG CTo about 1956 DEG C of strain point, for example, from about 600 DEG C to about 1000 DEG C, from about 600 DEG C to about 900 DEG C or from bigAbout 600 DEG C to about 800 DEG C.In other embodiments, glass preform have scope from about 700 DEG C to about 1956 DEG C,Answering from about 800 DEG C to about 1956 DEG C, from about 900 DEG C to about 1956 DEG C or from about 1000 DEG C to about 1956 DEG CHeight.The thickness of prefabrication can be in the range of such as about 0.70 to about 1.5mm.
It is preferred that feedback of the glass preform by downward component feeding 16 with scope from about 10mm/min to 12mm/minSpeed is sent to drive downwards.By the draw rate that traction device assembly 26 applies in the range of from about 0.2 to about 0.4m/min.For example, the draw rate applied by traction device assembly 26 can be about 0.3m/min, produced about in the centerline of glass tape2.8 pounds of stretching pulling force.
It will be apparent for a person skilled in the art that various modifications and variations can be made to the present invention without departing from this hairBright spirit and scope.Therefore it is contemplated that the modifications and variations of the present invention are covered, as long as these modifications and variations are appendedIn the range of appended claims and their equivalents.