CN102811959B - Production method for glass plate and glass plate production device - Google Patents

Abstract

The invention provides a production method for glass plates that uses the downdraw method, comprising a compression step, a temperature-raising step, a melting step, a molding step, and a cutting step. In the compression step, a molded body is compressed along one direction of the molded body, so as to restrict relative displacement of the molded body caused by increased molded body temperature. In the temperature-raising step, the ambient temperature for the compressed molded body is raised using a temperature-raising device. In the melting step, a glass raw material is melted to become molten glass. In the molding step, the molten glass is molded into sheet glass using the temperature-raised molded body. In the cutting step, the sheet glass is cut to form glass plates. As a result, reduction in glass plate quality is further minimized.

Description

The manufacture method of glass plate and device for producing glass sheet

Technical field

The present invention relates to manufacture method and the device for producing glass sheet of glass plate.

Background technology

In the past, there is the method that various methods such as utilizing drop-down (downdraw) method manufactures glass plate.Such as, as manufacturing in the overflow downdraw of a method of glass plate, first, the melten glass flowing into formed body is overflowed from formed body.Then, the melten glass overflowed is made to be configured as the laminal glass of continuous print (sheet glass) at interflow, the bottom of formed body.In addition, the sheet glass collaborated in the bottom of formed body is transported to below then.Then, sheet glass is cut into the size of expection and becomes glass plate.

At this, in order to tackle by the creep of conducting oneself with dignity or the weight etc. of melten glass of high temperature causes, the bottom of formed body is supported mostly.Such as, at patent document 1(Japan Patent No. 4193115 publication) disclosed in invention in, be configured with the support unit for supporting flow adjusting structure body respectively in the bottom of the two side ends of the length direction of flow adjusting structure body (being equivalent to formed body).Further, a support unit is subject to pressue device pressurization.

Summary of the invention

The problem that invention will solve

In general, melten glass during owing to being shaped is high temperature, before operation, therefore makes the temperature of the periphery of formed body raise, make the temperature of formed body increase.But, the intensification of pressue device to the temperature of the pressurization of support unit and the periphery of formed body can cause the position of formed body to offset, namely relative to the relative offset of other component parts in building mortion, by being offset the skew of the transport path of the sheet glass caused by this position, likely make the tractive force from roller that is subject to uneven.Thus, the quality of glass plate may be caused to reduce, such as, make the tilting of glass plate or the thickness deviation of glass plate increase.

And in recent years, there is the trend of slimming in the glass plate using glass tube down-drawing to produce.At this, thin glass plate, then be easilier out of shape because of little stress.Therefore, thin glass plate, the problem being offset the distortion of the glass plate that (offseting relative to the position of other component parts in building mortion) causes by the position of formed body is remarkable, and the position skew of wherein said formed body occurs because being warming up to high temperature.

In above-mentioned patent document 1, owing to not considering the position skew of above-mentioned formed body, therefore there is the problem of the distortion such as the tilting that cannot prevent from fully being offset the glass plate caused by the position of formed body.

In recent years, at liquid crystal display or organic EL(Electro-Luminescence, electroluminescent) flat-panel monitor (also referred to as FPD(Flat Panel Display) such as display) in, constantly pursue high-definition and the lightweight of picture display.In order to realize the lightweight of flat-panel monitor, also in the lightweight pursuing the glass plate that FPD comprises, therefore glass plate also exists the trend of further thin plate.On the other hand, in order to realize the high-definition of the picture display of FPD, also in the further reduction of the thickness deviation of the distortion such as tilting and glass plate of pursuing above-mentioned glass plate.Like this, the FPD such as liquid crystal display or organic el display glass plate needs is taken into account slimming and reduced tilt, but there is thin glass plate and then comprise the larger problem of the distortion of tilting.

Therefore, problem of the present invention is the manufacture method and the device for producing glass sheet that provide a kind of glass plate, can suppress the reduction of the quality of glass plate (such as, the increase comprising the distortion of tilting or the thickness deviation of glass plate of glass plate) further.

For solving the scheme of problem

The manufacture method of the glass plate that the present invention relates to is a kind of manufacture method that have employed the glass plate of glass tube down-drawing, and it comprises pressing process, heating process, melting operation, forming process and cut-out operation.In pressing process, press described formed body in the mode limiting the relative offset of the formed body caused by the intensification of formed body along a direction of described formed body.In heating process, the peripheral temperature of the formed body utilizing heat riser to make to be pressed heats up.In melting operation, frit is melted into melten glass.In forming process, utilize the formed body heated up that melten glass is configured as sheet glass.In cut-out operation, cut off sheet glass and form glass plate.At this, the reduction of the quality of glass plate can be suppressed further.

Preferably, described formed body is longer in a direction, in described pressing process, presses described formed body across the support unit supported the two side ends of the length direction of described formed body respectively.

And preferably, in heating process, the temperature of the periphery of formed body heats up with the programming rate of 5 DEG C ~ 30 DEG C/h.

And preferably, the thickness of slab of glass plate is at below 0.5mm.

And preferably, the tilting of glass plate is less than 0.2mm.

And, preferably, in pressing process, by applying support unit to be pressed into body from the outside of formed body towards the load on shaping side.

And preferably, described glass plate is the glass plate of liquid crystal display use or organic el display.

And the devitrification temperature of the glass that described glass plate adopts is 1050 DEG C ~ 1250 DEG C.

And, preferably, described glass plate contains respectively: the CaO of the Al2O3 of the SiO2 of 50 ~ 70 mass percents, the B2O3 of 0 ~ 15 mass percent, 5 ~ 25 mass percents, the MgO of 0 ~ 10 mass percent, 0 ~ 20 mass percent, SrO, the BaO of 0 ~ 10 mass percent of 0 ~ 20 mass percent, the RO(R of 5 ~ 20 mass percents for select from Mg, Ca, Sr and Ba, at least one in all the components contained by glass plate).

Further, preferably, the strain point of glass that adopts of described glass plate is more than 675 DEG C.

The prerequisite of the device for producing glass sheet that the present invention relates to is the device for producing glass sheet adopting glass tube down-drawing, in described glass tube down-drawing, the melten glass of inflow formed body is overflowed from formed body, then make the melten glass overflowed collaborate in the bottom of formed body, be configured as sheet glass thus.Device for producing glass sheet possesses support unit, heat riser, pressue device and control part.

Support unit is supported to the two side ends on a direction of body.

Heat riser makes the temperature of the periphery of formed body.

Pressue device is pressed into body from least one party at the both ends of formed body across support unit.

Control part controls, make utilize heat riser make the temperature of the periphery of formed body before utilize pressue device to carry out formed body pressing.In this device for producing glass sheet, the reduction of the quality of glass plate can be suppressed further, such as, can suppress the increase comprising the increase of the distortion of tilting and the thickness deviation of glass plate of glass plate further.

Invention effect

The present invention can suppress the reduction of the quality of glass plate further, such as, can suppress the increase comprising the increase of the distortion of tilting and the thickness deviation of glass plate of glass plate further.

Accompanying drawing explanation

Fig. 1 is the flow chart of the manufacture method of glass plate of the present embodiment.

Fig. 2 is the schematic diagram that the fusing device that device for producing glass sheet comprises mainly is shown.

Fig. 3 be the building mortion that comprises of device for producing glass sheet and the equipment being configured at building mortion periphery and parts, along sectional view when cutting open with the direction of horizontal plane.

Fig. 4 is the main schematic diagram of the summary of formed body.

Fig. 5 is the schematic diagram for illustrating the configuration from the secondary heater observation formed body of front.

Fig. 6 is the main schematic diagram of the summary of the formed body that variation 1A relates to.

Fig. 7 is the main schematic diagram of the summary of the formed body that variation 1B relates to.

Detailed description of the invention

Below, reference accompanying drawing is while illustrate the manufacture method adopting device for producing glass sheet 100 of the present embodiment to manufacture the glass plate of glass plate.

(1) summary of the manufacture method of glass plate

Fig. 1 is the flow chart of a part for the manufacture method of glass plate of the present embodiment.Below, adopt Fig. 1 that the manufacture method of glass plate is described.

As shown in Figure 1, glass plate melts operation ST1, clarification operation ST2, the working procedures of the operation ST3 that homogenizes, supply step ST4 and forming process ST5 and out manufactured through comprising.Below, these operations are described in detail.

In melting operation ST1, heating frit makes it melt.Frit is made up of compositions such as SiO2, Al2O3.Frit after melting completely becomes melten glass.

In clarification operation ST2, melten glass is clarified.Specifically, gas componant contained in melten glass is released from melten glass, or the gas componant contained in melten glass is absorbed in melten glass.

Homogenizing in operation ST3, melten glass is homogenized.In addition, in this operation, temperature adjustment is carried out to the melten glass after having clarified.

In supply step ST4, the building mortion 300(be supplied to by melten glass for forming melten glass is aftermentioned).In this operation, cooling melten glass is suitable for starting sheet glass SG(with reference to figure 3 to reach) the temperature of shaping.

In forming process ST5, melten glass is configured as laminal sheet glass SG.In the present embodiment, melten glass is configured as lamellar continuously by overflow downdraw, thus becomes sheet glass SG.Then, in cut-out operation, sheet glass SG is cut off every predetermined length, becomes glass plate G(with reference to figure 3).

In addition, after this, the glass plate G being cut to predetermined length in cut-out operation is cut off further, after having carried out grinding and grinding, cleaning, inspection, become glass plate (being called separately glass plate and additional label means the glass plate finally manufacturing and obtain), and be applied in the manufacture of the flat-panel monitors such as such as liquid crystal display etc.

(2) summary of device for producing glass sheet 100

Fig. 2 is the schematic diagram that the fusing device 200 that device for producing glass sheet 100 comprises mainly is shown.Fig. 3 be the equipment of the building mortion 300 that comprises of device for producing glass sheet 100 and the periphery that is configured at building mortion 300 and parts, along sectional view when cutting open with the direction of horizontal plane.Below, device for producing glass sheet 100 is described.

Device for producing glass sheet 100 mainly has fusing device 200(with reference to figure 2) and building mortion 300(referring to figs. 2 and 3).

(2-1) structure of fusing device 200

Fusing device 200 is the devices for carrying out melting operation ST1, clarification operation ST2, the operation ST3 and supply step ST4 that homogenizes.

As shown in Figure 2, fusing device 200 has melting groove 201, defecator 202, tank diameter 203, first pipe arrangement 204 and the second pipe arrangement 205.

Melting groove 201 is the grooves for melting frit.Melting operation ST1 is carried out at melting groove 201.

Defecator 202 is for from melting the groove removing bubble in groove 201 molten glass.By heating further from the melten glass melting groove 201 feeding in defecator 202, thus facilitate the deaeration of the bubble in melten glass.Clarification operation ST2 is carried out at defecator 202.

Tank diameter 203 has agitating device, and described agitating device comprises the storage container of melten glass, rotating shaft and is installed on multiple agitators of described rotating shaft.As container, rotating shaft and agitator, such as, can apply the parts be made up of the platinum family elements such as platinum or platinum family element alloy, but be not particularly limited.By utilizing the driving of drive division (not shown) to make rotating shaft rotate, the agitator being installed on rotating shaft stirs melten glass.Carry out homogenizing operation ST3 at tank diameter 203.

First pipe arrangement 204 and the second pipe arrangement 205 are such as the pipe arrangements be made up of platinum or platinum alloy.First pipe arrangement 204 is the pipe arrangements connecting defecator 202 and tank diameter 203.Second pipe arrangement 205 is the pipe arrangements connecting tank diameter 203 and building mortion 300.

(2-2) structure of building mortion 300

Building mortion 300 is the devices for forming operation ST5.

As shown in Figure 3, building mortion 300 has formed body 310, chill roll 330,330 and gives roller 350a ~ 350h.Below, these structures are described.

(2-2-1) formed body 310

Fig. 4 is the summary front view of the formed body 310 that building mortion 300 comprises.

As shown in Figure 3, formed body 310 is positioned at the upper section of building mortion 300, and has the function making the melten glass flow through from fusing device 200 be configured as laminal glass (i.e. sheet glass SG).The section shape obtained of vertically cutting open of formed body 310 has wedge-type shape, and formed body 310 is made up of the brick such as with fire resistance.

As shown in Figure 4, at formed body 310, be formed with supply port 311 at the upstream side in the direction (hereinafter referred to as first direction) of melten glass flowing.Flow through from fusing device 200 melten glass come and be supplied to formed body 310(building mortion 300 by this supply port 311).

As shown in Figure 3 or Figure 4, at formed body 310, the length direction along formed body 310 is formed with the groove portion 312 opened wide upward.Groove portion 312 is formed as shoaling gradually along with from the upstream side of first direction towards the downstream of first direction.

In addition, the formed body temperature sensor (not shown) as the detection means of the temperature being detected as body 310 is configured with respectively in the upstream side part of the first direction of formed body 310 and downstream part.

At formed body 310, the melten glass overflowed in groove portion 312 flows to below along the two sides of formed body 310, and collaborates in bottom 313.After this melten glass after bottom 313 is collaborated becomes laminal sheet glass plate SG and flows to below further.

(2-2-2) chill roll 330,330

Chill roll 330,330 is configured in the below of formed body 310.And chill roll 330,330 is configured in the both sides of the thickness direction of sheet glass plate SG, and be configured in the both sides of the width of sheet glass plate SG.Chill roll 330,330 is contacted by the sheet glass plate SG after collaborating with the bottom 313 at formed body 310 thus is cooled described sheet glass plate SG.And chill roll 330,330 is while being drawn into the thickness of expection by sheet glass plate SG, and the both ends of cooling sheet glass plate SG make its high viscosity, suppress the contraction of the width of thin plate.

(2-2-3) roller 350a ~ 350h is given

Give roller 350a ~ 350h to configure along the vertical direction in the below of chill roll 330,330 at predetermined spaced intervals.And, give the both sides that roller 350a ~ 350h is configured in the thickness direction of sheet glass plate SG, and below vertical direction, draw sheet glass plate SG.Thus, carry out annealing sheet glass plate SG is passed to elasticity territory from viscosity territory through viscoplasticity territory.

(2-3) equipment and the parts of the periphery of building mortion 300 are configured at

Device for producing glass sheet 100 also has following parts and equipment etc. except fusing device 200 and building mortion 300.

(2-3-1) partition member 320,320

As shown in Figure 3, partition member 320,320 be configured in formed body 310 bottom 313 near the parts of tabular.Specifically, partition member 320,320 is configured between formed body 310 and chill roll 330,330.Partition member 320,320 is configured in the both sides of the thickness direction of sheet glass plate SG in generally horizontal mode.Partition member 320,320 plays a role as heat-barrier material.That is, partition member 320,320 is by upper and lower spaced apart thus suppress heat to move from the downward side, upside of partition member 320,320 by it.

(2-3-2) heat insulating member 340a ~ 340h

Heat insulating member 340a ~ 340h is the parts of tabular, and it is configured along the vertical direction in the below of chill roll 330,330 at predetermined spaced intervals, and gives roller 350a ~ 350h with each and be alternately configured along the vertical direction.Heat insulating member 340a ~ 340h is configured in the both sides of the thickness direction of sheet glass plate SG in generally horizontal mode.By arranging multiple heat insulating member, add the space (heat insulating member neighbouring in multiple heat insulating member space each other) that can independently control, the adjustment of annealing conditions becomes easy.That is, glass plate generation internal strain can be suppressed efficiently.

(2-3-3) primary heater (not shown)

Primary heater is the equipment that the atmosphere temperature of the vicinity making sheet glass plate SG heats up, and it is configured with multiple with the width of sheet glass plate SG along the vertical direction.Primary heater is used for carrying out rightly controlling by the temperature of giving the sheet glass plate SG that roller 350a ~ 350h draws.

(2-3-4) secondary heater 380

Fig. 5 is the figure for illustrating the configuration from the secondary heater 380 front observation formed body 310.

Secondary heater 380 makes the heat riser of the temperature of formed body 310 play a role as by making the temperature of the periphery of formed body 310 (hereinafter referred to as peripheral temperature) heat up indirectly.In addition, peripheral temperature comprises the atmosphere temperature in the space being surrounded as body 310.As shown in Figure 5, secondary heater 380 is configured with multiple near formed body 310.Thereby, it is possible to make the surface temperature of formed body 310 heat up roughly equably, can reduce the generation of the breakage of the formed body 310 caused by thermal shock, the stress that this thermal shock is produced by the local temperature difference because of the formed body 310 when heating up causes.

(2-3-5) the first support unit 410 and the second support unit 420

As shown in Figure 4, in order to prevent the creep of the inferior portion of the central portion of formed body 310, the mode that the first support unit 410 contacts with the inferior portion of the two side ends of the length direction with formed body 310 with the second support unit 420 is configured respectively.Be supported to the inferior portion of the two side ends of the length direction of body 310 thus.Inferior portion refers to neutral line (or neutral surface) part on the lower than the bending moment produced at formed body 310.In addition, in general, the creep of formed body is considered to produce because of the weight etc. of the melten glass of its deadweight or high temperature.First support unit 410 and the second support unit 420 employ such as different from the thermal coefficient of expansion of the brick forming formed body 310 bricks, but are not limited thereto.

(2-3-6) pressue device

Cylinder is employed in pressue device.Pressue device is the pressue device by pressurizeing to the side in the first support unit 410 and the second support unit 420 to the first support unit 410 and the second support unit 420 imposed load.In the present embodiment, near the second support unit 420, pressue device 422 is configured.Specifically, pressue device 422 is configured in the position in the outside of the length direction by formed body 310 of the second support unit 420 across the plate member 421 that heat resistance is high.

In addition, in order to apply the compression stress of length direction to formed body 310 when pressue device 422 is to the second support unit 420 pressurization, near not pressurized support unit (in this case the first support unit 410), be configured with the fixed part for being fixed not pressurized support unit and equipment.In the present embodiment, near the first not pressurized support unit 410, fixed part and equipment 511 is configured with.More specifically, fixed part and equipment 511 are configured in the position in the outside of the length direction by formed body 310 of the first support unit 410 across the plate member 411 that heat resistance is high.

Thus, at least one party in the first support unit 410 and the second support unit 420 is pressurized, not pressurized support unit (in this case the first support unit 410) is subject to the reaction force (arrow P 1 in this case shown in Fig. 4) from fixed part or permanent plant (in this case fixed part and equipment 511).That is, the first support unit 410 and the second support unit 420 become and are applied with towards the state of the load of formed body 310 side (arrow P 1 shown in Fig. 4, P2) by pressue device 422.Thus, formed body 310 becomes the state pressed by the outside of the length direction from formed body 310 across the first support unit 410 and the second support unit 420.

(3) control device (not shown)

Control device is made up of CPU, ROM, RAM, hard disk etc.

Control device controls primary heater, secondary heater 380, pressue device 422 and the CD-ROM drive motor (not shown) etc. for driving chill roll 330,330 or giving roller 350a ~ 350h.That is, control device plays a role as the control part controlling the said equipment.Control device also can accept the input from user and carry out various control.And control device only setting example as one, also can arrange the multiple control device controlling above-mentioned CD-ROM drive motor, above-mentioned heater and pressue device respectively.Control for secondary heater 380 and pressue device 422 describes later.

(4) shaping of the sheet glass plate SG in building mortion 300

Below, the process making sheet glass plate SG be shaped in building mortion 300 is described.

First, as shown in Figure 4, flow to the groove portion 312 of formed body 310 by the melten glass that supply port 311 is supplied to formed body 310 from fusing device 200.Then, described melten glass overflows in groove portion 312.The melten glass overflowed in groove portion 312 flows downwards along the two sides of formed body 310, and collaborates in bottom 313 as illustrated in fig. 3.Then, the melten glass after bottom 313 is collaborated becomes laminal sheet glass plate SG and flows down downwards further.

Utilize the both ends being configured in the width of chill roll 330, the 330 grabbing thin plates glass plate SG of the both sides of the thickness direction of sheet glass plate SG drop-down and cool sheet glass plate SG below vertical direction.Utilize chill roll 330,330 drop-down sheet glass plate SG drop-down further by giving roller 350a ~ 350h downwards.Then, be cut off every predetermined length by the sheet glass plate SG giving roller 350a ~ 350h drop-down.

(5) setting of formed body 310

The setting of formed body 310 is carried out in the following manner: consider chill roll 330,330 and give the position of roller 350a ~ 350h etc., make formed body 310 be positioned at the primary importance that should normally install.Specifically, primary importance is such as by being fixed on the bottom 313 of formed body 310 and making the vertical below of described alignment hang down to determine by line.More specifically, primary importance be the line that makes to hang down downwards from the bottom 313 of formed body 310 not with partition member 320,320, chill roll 330,330, heat insulating member 340a ~ 340h with give roller 350a ~ 350h etc. and contact and pass straight through to the position till the space cut off by sheet glass plate SG.In addition, the defining method of primary importance is not limited thereto.

In addition, after being arranged to body 310, the first support unit 410 of two sides of the length direction being pre-configured in formed body 310 is contacted with the inferior portion of the two side ends of formed body 310 with the second support unit 420.Specifically, come the first support unit 410 and the second support unit 420 imposed load, by the first support unit 410 and the second support unit 420 by being pressed in formed body 310 by controlling pressue device 422.That is, formed body 310 is pressed by along a direction.Specifically, formed body 310 is pressed from the outside of length direction by across the first support unit 410 and the second support unit 420.

In addition, preferably, the opportunity that the pressurization of pressue device 422 to the second support unit 420 starts is that the temperature of formed body 310 reaches room temperature (referring to such as about 0 ~ 30 DEG C) or close to room temperature.Such as, consider the operating efficiency of constructor, preferably, the temperature of formed body 310 below 150 DEG C, more preferred below 100 DEG C, less than 80 DEG C, less than 50 DEG C, less than 30 DEG C, less than 25 DEG C.

Further, under the state utilizing pressue device 422 to be applied with predetermined pressure to the second support unit 420, reaffirm whether the position of formed body 310 is primary importances.Now, when the position of formed body 310 offset by (comprising inclination) relative to primary importance, stop pressue device 422, by such as adding between formed body 310 and the first support unit 410 or the second support unit 420 position that adhesive etc. is adjusted to body 310.In addition, the method for adjustment of the position of formed body 310 is not limited thereto.On the other hand, when formed body 310 is configured at primary importance, under the state predetermined pressure being applied with to the second support unit 420 by pressue device 422 (that is, under the state be pressed at formed body 310), start the hyperthermic treatment of formed body 310.

(6) intensification of formed body 310

Primary importance is arranged at and by pressue device 422 and fixed part and equipment 511 by under the state that press against at formed body 310, the temperature (such as, 1000 DEG C ~ 1200 DEG C) that the peripheral temperature that control device utilizes secondary heater 380 to be controlled to body 310 reaches predetermined to make the temperature of formed body 310.That is, control device controls secondary heater 380 based on the temperature of formed body 310.This is because the melten glass flowing to formed body 310 after operation starts is in the high temperature of about 1000 DEG C ~ 1400 DEG C, therefore needs the temperature making formed body 310 in advance.

At this, the peripheral temperature of formed body 310 heats up with predetermined programming rate.In addition, the peripheral temperature of formed body 310 and the surface temperature of formed body 310 are roughly the same temperature.That is, alternatively, the surface temperature of formed body 310 heats up with predetermined programming rate.

Preferably, predetermined programming rate is 5 DEG C ~ 30 DEG C/h.It is breakage in order to suppress the formed body caused by thermal shock that the upper limit of programming rate is preferably 30 DEG C/h.In addition, the upper limit of more preferred programming rate be followed successively by 10 DEG C/h, 12 DEG C/h, 15 DEG C/h.In this case, because the surface of formed body 310 can not become excessive, therefore, it is possible to be lowered into the possibility of the breakage of body 310 further with inner temperature difference.

And the heating-up time of the peripheral temperature of formed body is longer, likely have an impact to the productivity ratio of glass plate, therefore in order to avoid this situation, the lower limit of programming rate is preferably 5 DEG C/h.In addition, more preferably, the lower limit of programming rate is 7 DEG C/h.In this case, the productivity ratio of glass plate can be improved further.

(7) the preferred form of glass plate

Below the preferred form of the glass plate adopting the present invention to produce is described.In addition, following form is not limited to.

The thickness of glass plate is preferably 0.1mm ~ 3mm.And then the glass plate as flat-panel monitor is preferably 0.01 ~ 1.0mm.Further, according to preferred order, more preferred higher limit is followed successively by 0.4mm, 0.5mm, 0.8mm, 1.0mm, 1.5mm.Further, according to preferred order, more preferred lower limit is followed successively by 0.3mm, 0.2mm.Such as, for the glass plate of flat-panel monitor, for the reason pursuing lightweight and thin plate, the thickness of glass plate is thinner is more then preferred.On the other hand, the thickness of glass plate is thinner, and in display manufacturing operation, glass plate more easily breakage occurs.Consider these situations, the thickness of the glass plate of flat-panel monitor is preferably 0.01 ~ 1.0mm, is more preferably 0.1 ~ 0.8mm, and then is preferably 0.2 ~ 0.8mm.

Wherein, the thickness of glass plate at below 0.5mm, particularly less than 0.5mm, the skew of the position of formed body on the distortion of glass plate or the impact of breakage more remarkable.Is produced by the position skew because formed body, roller (chill roll and give roller) is to the deviation of the tractive force of glass plate applying, stress distribution is produced at glass plate, distortion or the breakage of glass plate can be caused in worst case, but when thickness is the glass plate of below 0.5mm, even little stress distribution also easily deforms and breakage.That is, the thickness of glass plate less than 0.5mm, be even below 0.4mm, then the effect of the present invention being suppressed to the position skew of body is more remarkable.Namely, the thickness of glass plate is in the words of more than 0.01mm below 0.5mm, effect of the present invention becomes remarkable, the thickness of described glass plate is at more than 0.01mm and less than the words of 0.5mm, effect of the present invention is more remarkable, the thickness of described glass plate is at more than 0.01mm below 0.4mm, and effect of the present invention is also more remarkable.

And the thickness deviation of glass plate is preferably 0 ~ 20 μm.Further, according to preferred order, the higher limit of the thickness deviation of more preferred glass plate is followed successively by less than 5 μm (such as 0 ~ 5 μm), less than 10 μm (such as 0 ~ 10 μm).In the present invention, such thickness deviation can be realized.

And preferably, when measuring, the maximum of the tilting of glass plate is in the scope of 0 to 0.2mm.Further, according to preferred order, the higher limit of the tilting of more preferred glass plate is followed successively by below 0.01mm (0 ~ 0.01mm), below 0.05mm (0 ~ 0.005mm), below 0.1mm (0 ~ 0.1mm), below 0.15mm (0 ~ 0.15mm).

The mensuration of the tilting of glass plate is described in further detail, first, cuts many pieces of platelets (about 400mm is square) from glass plate.Then, for each platelet, the tilting (that is, measuring the tilting amounting to 16 positions) between 4 positions in bight and 4 positions of central portion is measured respectively at positive and negative.Such as, when determining the tilting of 8 pieces of platelets, obtain the determination data of 16 position × 8 piece, the i.e. tilting at 128 positions.Further, preferably, the maximum in described determination data is in above-mentioned scope.In addition, in the present embodiment, using the maximum of tilting that measures in the multiple platelet tilting amount as glass plate.

And the size of glass plate is preferably, and the length of width is 500mm-3500mm, and the length of length direction is 500mm-3500mm.

And the kind of glass plate is preferably borosilicate glass, alumina silicate glass, Boroalumino silicate glasses, soda-lime glass, alkali silicate glass, alkali alumina silicate glass, alkali aluminum germanate glass.

And glass plate is preferably used as glass plate, panel used for solar batteries, the cover glass of flat-panel monitor (liquid crystal display, organic el display or plasma display etc.).In addition, cover glass refers to such as in order to protect the display frame of AV equipment (portable terminal device etc.) or casing to carry out the tempered glass of chemistry or physical strengthening to glass plate.At this, in recent years, liquid crystal display or organic el display were pursuing the display of high-precision picture, therefore required that reduction is used for the tilting of glass plate and the deviation of thickness of slab of liquid crystal display or organic el display.For this reason, the position that can be suppressed to body offsets and to reduce the present invention of the tilting of glass plate and thickness deviation more preferred.And higher surface quality pursued by the cover glass used for the cover as display part etc. etc.For this reason, the glass plate for cover glass is pursued and is reduced to tilt and thickness deviation, therefore, it is possible to the position being suppressed to body offsets and to reduce the present invention of the tilting of glass plate and thickness deviation more preferred.

And as the glass substrate of flat-panel monitor (liquid crystal display or plasma display etc.), citing illustrates the glass plate comprising the following compositions represented with mass percent.Shown in following bracket is the preferred content of each composition.Below, symbol % means mass percent.

SiO2：50～70%（55～65%，57～64%，58～62%）；

Al2O3：5～25%（10～20%，12～18%，15～18%）；

B2O3：0～15%（5～15%，6～13%，7～12%）。

Now, as optional member, also following compositions can be comprised.

MgO:0 ~ 10%(lower limit is 0.01%, and lower limit is 0.5%, and the upper limit is 5%, and the upper limit is 4%, and the upper limit is 2%);

CaO:0 ~ 20%(lower limit is 1%, and lower limit is 3%, and the upper limit is 4%, and the upper limit is 9%, and the upper limit is 8%, and the upper limit is 7%, and the upper limit is 6%);

SrO:0 ~ 20%(lower limit is 0.5%, and lower limit is 3%, and the upper limit is 9%, and the upper limit is 8%, and the upper limit is 7%, and the upper limit is 6%);

BaO:0 ~ 10%(upper limit is 8%, and the upper limit is 3%, and the upper limit is 1%, and the upper limit is 0.2%);

ZrO2：0～10%（0～5%，0～4%，0～1%，0～0.1%）。

And, particularly preferably be, containing SiO2 50 ~ 70%, B2O3 5 ~ 18%, Al2O3 10 ~ 25%, MgO 0 ~ 10%, CaO 0 ~ 20%, SrO 0 ~ 20%, BaO 0 ~ 10%, RO 5 ~ 20%(wherein, at least one in all compositions of R contained by the glass plate selected from Mg, Ca, Sr and Ba).Further, preferably, contained R ' 2O is (at least one wherein, in all compositions of R ' contained by the glass plate selected from Li, Na and K) more than 0.20% and below 2.0%.And, preferably, amount to the fining agent containing 0.05 ~ 1.5%, and in fact not containing As2O3, Sb2O3 and PbO.And the amount of the iron oxide also in preferred glass is 0.01 ~ 0.2%.

And, preferably, containing SiO2 50 ~ 70%, B2O3 0 ~ 15%, Al2O3 5 ~ 25%, MgO 0 ~ 10%, CaO 0 ~ 20%, SrO 0 ~ 20%, BaO 0 ~ 10%, RO 5 ~ 20%(wherein, at least one in all compositions of R contained by the glass plate selected from Mg, Ca, Sr and Ba).

And, when glass plate is used for the glass substrate of flat-panel monitor, from suppressing the TFT(Thin Film Transistor being formed at the glass substrate of flat-panel monitor, TFT) the viewpoint of destruction set out, preferred glass plate is alkali-free glass (in fact the glass of alkali-free composition).On the other hand, in order to improve the meltability of glass, still can containing micro-alkaline components.In this case, preferably, contained R ' 2O is (at least one wherein, in all compositions of R ' contained by the glass plate selected from Li, Na and K) more than 0.05% and below 2.0%, more preferably, contained R ' 2O is more than 0.1% and below 2.0%.And preferably, fining agent is not in fact containing As2O3 and PbO.And preferably, fining agent is at least containing tin oxide.And the amount of the iron oxide also in preferred glass is 0.01 ~ 0.2%.

For the light-weighted object of flat-panel monitor, preferred SrO+BaO is 0 ~ 10%.And on the basis of light-weighted viewpoint, then consider carrying capacity of environment, also preferred BaO is 0 ~ 2 mass percent.

By making the glass of glass plate become compositing range as described above, the glass plate of the characteristic (suppression and lightweight to the destruction of TFT) required by the glass substrate meeting the flat-panel monitor such as liquid crystal display or organic el display can be formed.In more detail, can realize meeting the glass plate of strain point more than 650 DEG C.And, the glass plate of density at below 2.6g/cm3 can be realized.And, the glass plate of Young's modulus at more than 70GPa can be realized.And, the glass plate of devitrification temperature below 1250 DEG C can be realized.The glass plate of devitrification temperature below 1250 DEG C can adopt overflow downdraw manufacture.But, be difficult owing to not only realizing the above-mentioned characteristic (suppression and lightweight to the destruction of TFT) of devitrification temperature less than 1050 DEG C but also required by the glass substrate meeting flat-panel monitor, therefore preferably devitrification temperature is 1050 DEG C ~ 1250 DEG C.

At this, melten glass is remained near devitrification temperature for a long time, meeting crystallization from melten glass, thus produce devitrification.Therefore, the temperature of the melten glass flowed down at the near wall of formed body 310 needs to keep higher than devitrification temperature.Therefore, require after the melten glass flowed down from formed body 310 leaves, the temperature of melten glass is near devitrification temperature, and then the temperature of melten glass is cooled hastily, thus avoid producing devitrification at melten glass.That is, preferably, the temperature of the melten glass flowed at the near wall of formed body 310 is higher more than 10 DEG C than devitrification temperature, more preferably, high than devitrification temperature more than 20 DEG C.By making the temperature of described melten glass higher than devitrification temperature more than 10 DEG C, even if produce heat radiation from the supporting brick of formed body 310 and make the generation of the temperature of melten glass uneven, or because melting out composition from supporting brick, glass is formed produce uneven and then the uneven situation of devitrification temperature occurs, also can suppress the generation of devitrification fully.

Like this, when manufacturing glass plate at the glass substrate as the flat-panel monitor such as liquid crystal display or organic el display, preferably, devitrification temperature reaches the high temperature of 1050 DEG C ~ 1250 DEG C, and the temperature of the formed body 310 therefore in glass substrate manufacture also needs to reach 1050 DEG C ~ 1350 DEG C.At this, make formed body 310 from normal temperature after intensification, when melten glass starts to flow to formed body 310, there is gap in melten glass temperature and formed body temperature, can damage formed body 310 because of this temperature difference.Therefore, preferably make formed body 310 heat up in advance, if but manufacture the higher glass of devitrification temperature, the temperature of intensification is larger.Consequently, the position skew of the formed body 310 during above-mentioned intensification easily occurs.Thus, when manufacturing glass plate at the glass substrate reaching the flat-panel monitors such as the liquid crystal display of high temperature of 1050 DEG C ~ 1250 DEG C or organic el display as devitrification temperature, even if it is preferred for formed body 310 being warming up to 1050 DEG C ~ 1350 DEG C the present invention that also can be suppressed to the positions skew of body 310.

And as the glass plate being applied to glass substrate used for solar batteries, citing illustrates the glass plate such as comprising the following compositions represented with mass percent.Display in following bracket is the preferred content of each composition.

SiO2：50～70%（55～65%，57～64%，57～62%）；

Al2O3：5～20%（9～18%，12～17%）；

Na2O：6～30%（7～20%，8～18%，10～15%）。

Now, as optional member, also following compositions can be comprised.

Li2O：0～8%（0～6%，0～2%，0～0.6%，0～0.4%，0～0.2%）；

B2O3：0～5%（0～2%，0～1%，0～0.8%）；

K2O:0 ~ 10%(lower limit is 1%, and lower limit is 2%, and the upper limit is 6%, and the upper limit is 5%, and the upper limit is 4%);

MgO:0 ~ 10%(lower limit is 1%, and lower limit is 2%, and lower limit is 3%, and lower limit is 4%, and the upper limit is 9%, and the upper limit is 8%, and the upper limit is 7%);

CaO:0 ~ 20%(lower limit is 0.1%, and lower limit is 1%, and lower limit is 2%, and the upper limit is 10%, and the upper limit is 5%, and the upper limit is 4%, and the upper limit is 3%);

ZrO2：0～10%（0～5%，0～4%，0～1%，0～01%）。

Particularly preferably be, as chemical enhanced cover glass or glass plate used for solar batteries, containing SiO2 50 ~ 70%, Al2O3 5 ~ 20%, Na2O 6 ~ 30%, K2O 0 ~ 10%, MgO 0 ~ 10%, CaO 0 ~ 20%.

In addition, in recent years, in order to realize the further high-definition of the picture display of flat-panel monitor, pursuing and adopting P-Si(low temperature polycrystalline silicon) TFT or oxide semiconductor instead of α-Si(amorphous silicon) display of TFT.At this, at P-Si(low temperature polycrystalline silicon) in the formation process of TFT or oxide semiconductor, there is the heat treatment step more taller than the formation process temperature of α-SiTFT.Therefore, little for the glass plate needs percent thermal shrinkage forming P-SiTFT or oxide semiconductor.In order to reduce percent thermal shrinkage, preferably improve strain point, but the high glass of strain point also exists the trend that devitrification temperature raises.In order to suppress devitrification, needing melten glass temperature when being shaped to keep higher than devitrification temperature, therefore in order to manufacture the high glass plate of devitrification temperature, needing to improve the temperature of atmosphere in building mortion 300 and formed body 310.At this, atmosphere temperature in building mortion 300 raises, and the problem that the problem producing gap between formed body 310 and support unit that causes because producing distortion or frictional resistance between formed body 310 and support unit and position offset easily occurs.That is, the glass adopting such as strain point more than 655 DEG C to manufacture glass plate time, the present invention is preferred.Particularly adopt concerning P-SiTFT or oxide semiconductor be preferred, strain point more than 675 DEG C or the glass of strain point more than 680 DEG C to manufacture glass plate time, the present invention is more preferred, when adopting the glass of strain point more than 690 DEG C to manufacture glass plate, the present invention particularly preferably.

And, when adopting devitrification temperature to manufacture glass plate at the glass of 1100 DEG C ~ 1250 DEG C, the present invention is preferred, when adopting devitrification temperature to manufacture glass plate at the glass of 1150 DEG C ~ 1250 DEG C, the present invention is more preferred, and when adopting devitrification temperature to manufacture glass plate at the glass of 1180 DEG C ~ 1250 DEG C, the present invention also will be more preferably, when adopting devitrification temperature to manufacture glass plate at the glass of 1200 DEG C ~ 1250 DEG C, the present invention particularly preferably.

When by strain point, more than 675 DEG C, the glass of (or devitrification temperature is 1150 ~ 1250 DEG C) is used for glass plate, as glass composition, such as citing illustrates the glass plate comprising the following compositions represented with mass percent.Symbol % shown below means mass percent.

Comprise SiO2 52 ~ 78%, Al2O3 3 ~ 25%, B2O3 3 ~ 15%, RO(wherein, R for select from Mg, Ca, Sr and Ba, at least one in all compositions contained by glass plate) 3 ~ 20%, mass ratio (SiO2+Al2O3)/B2O3 is in the scope of 7 ~ 20.

Further, in order to make strain point raise further, preferred mass ratio (SiO2+Al2O3)/RO is more than 7.5.Further, in order to make strain point raise, preferred β-OH value is 0.1 ~ 0.3mm.Further, for the viewpoint of the destruction of suppression TFT, alkali-free glass (in fact the glass of alkali-free composition) is preferably.On the other hand, flow to prevent electric current when melting and melt groove 201 instead of flow to glass, can containing 0.01 ~ 0.8% R2O(wherein, R for select from Li, Na and K, at least one in all compositions contained by glass plate) resistivity of glass is reduced.Or, in order to make the resistivity of glass reduce, preferably contain the Fe2O3 of 0.01 ~ 1%.Further, in order to not only realize higher strain point but also prevent the rising of devitrification temperature, preferred CaO/RO is more than 0.65.In addition, by making devitrification temperature below 1250 DEG C, overflow downdraw can be applied.And consider mobile devices such as being applied to mobile communication terminal, from light-weighted viewpoint, the total amount of SrO and BaO in preferred glass plate is more than 0% and less than 2%.

(each composition)

SiO2 is the composition of the skeleton of the glass forming glass plate, has and improves the chemical durability of glass and the effect of heat resistance.When the content of SiO2 is too low, the effect of chemical durability and heat resistance fully cannot be obtained, and the too high levels of SiO2, easily cause glass devitrification, being shaped becomes difficulty, and viscosity rises, and homogenizing of glass becomes difficulty.

Al2O3 is the composition of the skeleton forming glass, has and improves the chemical durability of glass and the effect of heat resistance.And, there is the effect improving etching speed.When the content of Al2O3 is too low, the chemical durability of glass and the effect of heat resistance fully cannot be obtained.On the other hand, the too high levels of Al2O3, the viscosity of glass rises, and melts and becomes difficulty, and acid resistance reduces.

B2O3 be reduce glass viscosity, promote the melting of glass and the composition of clarification.The content of B2O3 is too low, and the acid resistance of glass reduces, and homogenizing of glass becomes difficulty.

MgO and CaO be reduce glass viscosity, promote the melting of glass and the composition of clarification.And in alkaline-earth metal, the ratio that Mg and Ca makes the density of glass rise is less, it is therefore the composition being conducive to not only making obtained glass lightweight but also improving meltability.But, the too high levels of described MgO and CaO, the chemical durability of glass reduces.

SrO and BaO be reduce glass viscosity, promote the melting of glass and the composition of clarification.And, SrO and BaO be also improve frit oxidisability, improve clarification composition.But, the too high levels of SrO and BaO, the density of glass rises, and cannot realize the lightweight of glass plate, and the chemical durability of glass reduces.

Li2O be reduce glass viscosity, improve the meltability of glass and the composition of formability.And Li2O is the composition making the Young's modulus of glass raise.But, the too high levels of Li2O, the easy devitrification of glass, thus be difficult to apply glass tube down-drawing.

Na2O and K2O be reduce glass high temperature viscosity, improve the meltbility of glass and the composition of formability.And Na2O and K2O is the composition of the devitrification resistance improving glass.When the content of Na2O or K2O is too low, the meltability of glass reduces, and the cost needed for melting raises.And glass easily devitrification occurs, devitrification resistance also reduces, and is thus difficult to apply the glass tube down-drawing making glass overflow.On the other hand, the too high levels of Na2O or K2O, also can produce the devitrification resistance that the deterioration that balanced by glass causes and reduce.

In addition, Li2O, Na2O and K2O likely melt out and make TFT deterioration in characteristics and likely increase the thermal coefficient of expansion of glass and make the composition of substrate damage when heat treatment from glass, therefore, at the glass substrate as flat-panel monitor (such as, the glass substrate of liquid crystal display, the glass substrate of organic el display) when applying, do not wish that, containing a large amount of Li2O, Na2O and K2O, its total amount should be limited in below 2.0 mass percents.But, by making the mentioned component in glass or containing specified quantitative, the thermal expansion of the deterioration of TFT characteristic and glass can either be suppressed in fixed range, turn improving the basicity of glass, the oxidation of the metal that valence mumber is changed becomes easy, can play clarification.

ZrO2 be improve glass devitrification temperature near viscosity and the composition of strain point.And ZrO2 is also the composition making the heat resistance of glass improve.But, the too high levels of ZrO2, devitrification temperature rises, and devitrification resistance reduces.

TiO2 is the composition that the high temperature viscosity of glass is reduced.But, the too high levels of TiO2, devitrification resistance reduces.Further, glass is colored, and is not suitable for the cover glass etc. of the display frame being applied to electronic equipment.And, because glass is colored, so ultraviolet ray transmissivity reduces, therefore when carrying out the process employing ultraviolet hardening resin, the problem that can not ultraviolet hardening resin be made fully to harden can be produced.

In the frit of glass plate, as the composition of the bubble deaeration made in glass, fining agent can be added.As fining agent, as long as carrying capacity of environment is little, the composition of the clarification excellence of glass is not just restricted especially, at least one selected from the metal oxide of such as tin oxide, iron oxide, cerium oxide, terbium oxide, molybdenum oxide and tungsten oxide and so on can be enumerated.

At this, the requirement of glass substrate to bubble of the flat-panel monitor such as liquid crystal display or organic el display is strict especially.Thus, as the fining agent of the manufacture for glass plate, preferably at least containing the extra high tin oxide of clarifying effect in the metal oxide of tin oxide, iron oxide, cerium oxide, terbium oxide, molybdenum oxide and tungsten oxide and so on.

In addition, As2O3, Sb2O3 and PbO occur to change adjoint reaction with valence mumber, have the material of the effect of fining glass in melten glass, but because As2O3, Sb2O3 and PbO are the materials that carrying capacity of environment is larger, therefore in the glass plate of present embodiment, in glass in fact not containing As2O3, Sb2O3 and PbO.In addition, in this manual, do not mean less than 0.01 mass percent containing As2O3, Sb2O3 and PbO in fact, deliberately do not contain except impurity.

(8) feature

（8-1）

In the past, in order to tackle by the creep of conducting oneself with dignity or the weight etc. of melten glass of high temperature causes, the bottom of formed body was supported mostly.Such as, at patent document 1(Japan Patent No. 4193115 publication) in invention disclosed, be configured with the support unit for supporting flow adjusting structure body respectively in the bottom of the two side ends of the length direction of flow adjusting structure body (being equivalent to formed body).Further, a support unit is pressurizeed by pressue device.

At this, in general, due to the high temperature that the melten glass being supplied to formed body is about 1000 DEG C ~ 1400 DEG C, therefore start to make melten glass flow to formed body 310 under the state not making formed body 310 heat up, can damage because of the temperature official post formed body 310 of melten glass and formed body 310.Therefore, after formed body starts, make the temperature of the periphery of formed body.But, because pressue device is to the intensification of the temperature of the pressurization of support unit and the periphery of formed body, likely causes the position of formed body to offset, thus the transport path of sheet glass is offset.Therefore, worry that the tractive force be subject to from roller (chill roll and give roller) becomes uneven, the quality of glass plate reduces.

And, in recent years, use the glass plate of glass tube down-drawing manufacture to there is the trend of slimming.At this, thin glass plate is then easier to be out of shape because of little stress.Therefore, thin glass plate, the problem being offset the distortion of the glass plate caused by the position of above-mentioned formed body is remarkable.

Therefore, in the present embodiment, control device presses (being equivalent to pressing process) formed body 310 making the direction, one, forward position of the peripheral temperature intensification of formed body 310.Specifically, control device is pressed into body 310 by controlling pressue device 422 to a direction.More specifically, body 310 is pressed into along its length.Now, pressue device 422 pressurizes to formed body 310 side, thus to the first support unit 410 and the second support unit 420 imposed load (imposed load) to the second support unit 420.Then, the second support unit 420 pressurizeed by pressue device 422 is pressed into the two side ends of the length direction of body 310.Thus, the relative position caused by heating up being constrained to body 310 by the first support unit 410 and the second support unit 420 is offset, and then is fixed into body 310.Particularly by being pressed into the inferior portion of the two side ends of the length direction of body 310, the creep of the inferior portion of body 310 can be suppressed to.

Then, control device is being pressurizeed to the second support unit 420 by pressue device 422, is being applied with the state of load (namely to the first support unit 410 and the second support unit 420, be pressed into the state of body 310) under, make the peripheral temperature of formed body 310 heat up (being equivalent to heating process) by secondary heater 380.By being pressed into body 310 along the length direction of formed body 310, the position caused by heating up that effectively can be suppressed to body 310 offsets.

In the present embodiment, by applying towards the load in the direction of formed body 310 to the first support unit 410 and the second support unit 420, first, the action of the first support unit 410 and the second support unit 420 is limited.And, by applying the load from the outside of formed body 310 towards formed body 310 side to the first support unit 410 under this state and the second support unit 420, thus limit the position skew (the relative position caused by heating up of formed body 310 offsets) of the inferior portion (and even formed body 310 is overall) of the two side ends of the length direction of formed body 310 via the first support unit 410 and the second support unit 420, and then secure formed body 310.Then, the peripheral temperature of formed body 310 is made to heat up in this condition, therefore, it is possible to be suppressed to the position skew comprising inclination of body 310.

At this, if there is the position skew of formed body, worry following impact to I haven't seen you for ages.First, when the shaping of sheet glass, the table back side of sheet glass or the Temperature Distribution of width produce uneven, and the thickness of slab of sheet glass easily produces uneven (thickness deviation).When the thickness of slab of sheet glass produces uneven, this melten glass flowed down or sheet glass and the distance be covered between the furnace wall of stove of body etc. or heater offset relative to the distance inferred.Therefore, on the width of sheet glass, the difference of the temperature of actual sheet glass and fiducial temperature (temperature of glass plate when formed body being arranged on desirable position) can be produced.In this case, in gradually cooling working procedure (in the present embodiment, be equivalent to utilize and give roller 350a ~ 350h operation of drawing sheet glass downwards), also impact is had to the control of the temperature of the width of sheet glass.Therefore, the internal strain that cannot remove glass plate is fully worried.And owing to inferring that the transport path of the sheet glass offsets, what therefore sheet glass was subject to becomes unfixing from the tractive force giving roller, worrying that glass plate tilts.Further, worry that the bonding of melten glass in formed body lower end produces unfavorable condition.

In addition, as the position skew of the formed body occurred, be speculated as the side's skew in the upstream side of the first direction of such as formed body and downstream, thus form the position relationship of " distortion " with the various rollers being configured at below.In this case, as mentioned above, owing to offseting time the heater or roller etc. that are arranged on below are positioned at correct position with the position relationship of sheet glass compared to formed body, therefore worry that the Temperature Distribution generation of sheet glass is uneven.

On the other hand, in the present embodiment, due to the position skew of body 310 can be suppressed to, therefore, it is possible to maintain the quality of glass plate.That is, the thickness deviation of glass plate can be suppressed and comprise the distortion of tilting.

Formed body as described above position skew be because: such as when the temperature of the periphery of formed body, the support unit configured to prevent the creep of formed body or formed body expand.Now, infer frictional resistance because producing between support unit and formed body or distortion and the position skew of formed body occurs.Further, infer and pressurizeed to support unit by pressue device in this condition, the offset of formed body run-off the straight equipotential moves.

In general, brick for formed body 310 preferably not only has fire resistance and heat resistance but also can suppress the formed body special brick containing ZrO2 etc. of creep, on the other hand, the brick used in the support unit comprising the first support unit 410 and the second support unit 420 preferably has the brick of fire resistance and heat resistance.Such as, if the hard-core words when the expansion that the heating by formed body 310 causes, formed body 310 and support unit can move freely respectively, between formed body 310 and support unit, produce distortion or frictional resistance, occur in the problem that forms gap between formed body 310 and support unit thus or the problem that position offsets occurs.On the other hand, as in the present embodiment, before the heating of formed body 310 to formed body 310 along a direction, be preferably the length direction words of pressurizeing in advance, formed body 310 becomes to be integrated with support unit, the contact surface between body 310 and support unit can be maintained in, therefore, it is possible to carry out the restriction of expansion direction.

On the other hand, in the present embodiment, as mentioned above, by applying towards the load in the direction of formed body 310 to the first support unit 410 and the second support unit 420, thus limit the relative position skew caused by heating up of formed body 310 via the first support unit 410 and the second support unit 420, and then formed body 310 is fixed.Further, owing to making the peripheral temperature of formed body 310 heat up in this condition, therefore, it is possible to be suppressed to the position skew comprising inclination of body 310.

（8-2）

The programming rate of the peripheral temperature of formed body 310 is 5 DEG C ~ 30 DEG C/h, thereby, it is possible to be suppressed to the breakage of body 310, and can suppress the reduction of the productivity ratio of glass plate.

In addition, the programming rate of the peripheral temperature of formed body 310 is more preferably 5 ~ 20 DEG C/h, and then is preferably 5 ~ 15 DEG C/h, and then is preferably 6 DEG C ~ 10 DEG C/h.In this case, the possibility of the breakage of body 310 can either be lowered into further, the productivity ratio of glass plate can be improved again.

（8-3）

In the present embodiment, by pressue device 422, second support unit 420 is pressurizeed, thus to the first support unit 410 and the second support unit 420 imposed load.

At this, by adopting the pressue devices 422 such as cylinder, can simply to the first support unit 410 and the second support unit 420 imposed load.

(9) variation

Above, based on illustrating embodiments of the present invention, but concrete structure is not limited to above-mentioned embodiment, can change in the scope of purport not departing from invention.

(9-1) variation 1A

Fig. 6 is the summary front view of the formed body 310 that this variation 1A relates to.

In the above-described embodiment, describe and utilize pressue device to the side's pressurization in the first support unit 410 and the second support unit 420, but be not limited thereto, pressue device also can be utilized all to pressurize to the first support unit 410 and the second support unit 420.

In this case, as shown in Figure 6, near the first support unit 410, also pressue device 412 is configured across plate member 411.

Further, the first support unit 410 and the second support unit 420 press (arrow P 3 shown in Fig. 6, P2) by pressue device 412,422 to formed body 310 side respectively.Thus, the relative position caused by heating up of formed body 310 offsets and is limited, and then formed body 310 is fixed.Thus, in this case, the position skew of body 310 can be also suppressed to.

(9-2) variation 1B

Fig. 7 is the summary front view of the formed body 310 that this variation 1B relates to.

Such as, when the first support unit 410 or the such support unit being supported to body 310 of the second support unit 420 are placed in mounting parts, infer frictional resistance because producing between support unit and mounting parts or distortion and position that support unit occurs offsets.Further, utilize pressue device to support unit pressurization in this condition, worry that the offset of formed body inclination equipotential occurs to move.

At this, as long as mounting parts realize the parts of the function of mounting support unit, such as, can be base, also as illustrated in fig. 7, block parts 611,612 can be adopted.In addition, multiple block parts 611,612 can be configured.

But, even under these circumstances, by adopting the structure identical with above-mentioned embodiment and method, before the heating of formed body 310 to formed body 310 along a direction, be preferably length direction pressurization words, formed body 310 becomes to be integrated with support unit, the contact surface between body 310 and support unit can be maintained in, therefore, it is possible to realize the restriction of expansion direction.Namely, the relative position caused by heating up being limited formed body 310 by the first support unit 410 and the second support unit 420 is offset, and then under the state to be fixed at formed body 310, peripheral temperature is heated up, therefore, it is possible to be suppressed to the position skew of body 310, the quality of glass plate can be maintained, that is, the increase of the distortion tilting of glass plate can be prevented, being caused by internal strain, and then damage can be prevented.Therefore, even the present invention is also useful under these circumstances.

In addition, in this variation, brick for formed body 310 also preferably not only has fire resistance and heat resistance but also can suppress the formed body special brick containing ZrO2 etc. of creep, on the other hand, the brick used in the support unit comprising the first support unit 410 and the second support unit 420 and block parts 611,612 preferably has the brick of fire resistance and heat resistance.

(9-3) variation 1C

In the above-described embodiment, describing the parts being supported to body 310 is the first support unit 410 and the second support unit 420 these two, but is not limited thereto, and also can have more multi-support parts.And the first support unit 410 and the second support unit 420 also can be the parts that one is formed.

(9-4) variation 1D

Except above-mentioned embodiment, such as, also can be the swell increment precalculating formed body 310, first support unit 410 and the second support unit 420, thus reduce the displacement of the piston of the cylinder used as pressue device.

(9-5) variation 1E

In the above-described embodiment, adopt cylinder as pressue device, but be not limited thereto, also can apply known pressue device.

Embodiment

Below, embodiments of the invention are described.

In embodiment 1, inventor, before the peripheral temperature intensification making formed body 310, starts the pressing via the first support unit 410 and the second support unit 420 pairs of formed bodies 310.Then, after the pressing to formed body 310, the peripheral temperature of formed body 310 is heated up with the programming rate of 10 DEG C/h.After this, in the mode of the composition shown in below becoming, frit is melted and becomes melten glass, and carried out the clarification to melten glass.Then, the melten glass after utilizing tank diameter to stir clarification, is supplied to the formed body 310 after being heated up by above-mentioned method by the melten glass after stirring, thus is configured as sheet glass.Then, cut off sheet glass, produce the glass plate that thickness is 0.7mm, size is the liquid crystal display of 2200mm × 2500mm.In addition, the devitrification temperature of the glass plate of the display produced is 1170 DEG C, and strain point is 670 DEG C.

SiO2 60%

Al2O3 19.5%

B2O3 10%

CaO 5%

SrO 5%

SnO2 0.5%

And as embodiment 2, present inventor becomes except 0.4mm except making the thickness of the glass plate produced, and has also manufactured the glass plate of display with the method same with above-described embodiment 1.

Then, cut the glass plate of 380mm × 420mm from the glass plate of the liquid crystal display produced by embodiment 1 and embodiment 2 respectively, and determine the tilting of these glass plates.Now, the tilting of these glass plates is all at below 0.15mm.Therefore, the tilting of the glass plate of the liquid crystal display of 2200mm × 2500mm is also at below 0.15mm.

As embodiment 3, present inventor, before the peripheral temperature intensification making formed body 310, starts the pressing via the first support unit 410 and the second support unit 420 pairs of formed bodies 310.Then, after the pressing to formed body 310, the peripheral temperature of formed body 310 is heated up with the programming rate of 10 DEG C/h.After this, in the mode of the composition (representing with mass percent) shown in below becoming, frit is melted and becomes melten glass, and carried out the clarification to melten glass.Then, the melten glass after utilizing tank diameter to stir clarification, is supplied to the formed body 310 after being heated up by above-mentioned method by the melten glass after stirring, thus is configured as sheet glass.Then, cut off sheet glass, produce the glass plate that thickness is 0.7mm, size is the liquid crystal display of 2200mm × 2500mm.In addition, the devitrification temperature of the glass plate of the liquid crystal display produced is 1230 DEG C, and strain point is 715 DEG C.

SiO2 61.5%

Al2O3 20%

B2O3 8.4%

CaO 10%

SnO2 0.1%

And as embodiment 4, present inventor becomes except 0.4mm except making the thickness of the glass plate produced, and has also manufactured the glass plate of liquid crystal display with the method same with above-described embodiment 3.

Then, cut the glass plate of 380mm × 420mm from the glass plate of the liquid crystal display produced by embodiment 3 and embodiment 4 respectively, and determine the tilting of these glass plates.Now, the tilting of these glass plates is all at below 0.15mm.Therefore, the tilting of the glass plate of the liquid crystal display of 2200mm × 2500mm is also at below 0.15mm.

In addition, as comparative example 1, present inventor make the peripheral temperature of formed body 310 at a predetermined velocity (in this case 10 DEG C/h) start the pressing to formed body 310 after being warming up to predetermined temperature (in this case 1200 DEG C), carried out the manufacture of glass plate according to the method identical with embodiment 1 in addition.

And, as comparative example 2, present inventor make the peripheral temperature of formed body 310 at a predetermined velocity (in this case 10 DEG C/h) start the pressing to formed body 310 after being warming up to predetermined temperature (in this case 1200 DEG C), carried out the manufacture of glass plate according to the method identical with embodiment 2 in addition.

And, as comparative example 3, present inventor make the peripheral temperature of formed body 310 at a predetermined velocity (in this case 10 DEG C/h) start the pressing to formed body 310 after being warming up to predetermined temperature (in this case 1200 DEG C), carried out the manufacture of glass plate according to the method identical with embodiment 3 in addition.

And, as comparative example 4, present inventor make the peripheral temperature of formed body 310 at a predetermined velocity (in this case 10 DEG C/h) start the pressing to formed body 310 after being warming up to predetermined temperature (in this case 1200 DEG C), carried out the manufacture of glass plate according to the method identical with embodiment 4 in addition.

Then, cut the glass plate of 380mm × 420mm from the glass plate (2200mm × 2500mm) of the liquid crystal display produced respectively, and determine the tilting of glass plate.Now, the tilting maximum of the glass plate of comparative example 1 and comparative example 3 has exceeded 0.20mm.And the tilting maximum of the glass plate of comparative example 2 and comparative example 4 has exceeded 0.30mm.

Thus, the present invention is useful in the quality improving glass plate.

Industrial utilizability

The present invention can be applied to various use building mortion in the manufacture method manufacturing the glass plate of glass plate and device for producing glass sheet.

Label declaration

100: device for producing glass sheet;

300: building mortion;

310: formed body;

380: secondary heater (heat riser);

410: the first support units (support unit);

412,422: pressue device;

420: the second support units (support unit);

G: glass plate;

SG: sheet glass.

Claims (11)

1. a manufacture method for glass plate, the manufacture method of this glass plate have employed glass tube down-drawing, it is characterized in that,

The manufacture method of this glass plate possesses following operation:

Pressing process, in pressing process, presses described formed body in the mode limiting the relative offset of the formed body caused by the intensification of formed body along a direction of described formed body;

Heating process, in heating process, the peripheral temperature of the described formed body utilizing heat riser to make to be pressed heats up;

Melt operation, in melting operation, frit is melted into melten glass;

Forming process, in forming process, utilizes the described formed body heated up that described melten glass is configured as sheet glass; And

Cut off operation, in cut-out operation, cut off described sheet glass and form glass plate,

Utilizing before described heat riser makes the heating process of the temperature of the periphery of formed body, utilizing the pressing that pressurization operation is carried out formed body,

Described heat riser is configured with multiple near formed body, and the surface temperature of formed body is heated up equably,

Described peripheral temperature comprises the atmosphere temperature in the space being surrounded as body.

2. the manufacture method of glass plate according to claim 1, wherein,

Described formed body is longer in a direction,

In described pressing process, press described formed body across the support unit supported the two side ends of the length direction of described formed body respectively.

3. the manufacture method of glass plate according to claim 1 and 2, wherein,

In described heating process, the temperature of the periphery of described formed body heats up with the programming rate of 5 DEG C ~ 30 DEG C/h.

4. the manufacture method of glass plate according to claim 1 and 2, wherein,

The thickness of slab of described glass plate is at below 0.5mm.

5. the manufacture method of glass plate according to claim 1 and 2, wherein,

The tilting of described glass plate is less than 0.2mm.

6. the manufacture method of glass plate according to claim 1 and 2, wherein,

In described pressing process, by applying described support unit, from the outside of described formed body towards the load on described shaping side, to press described formed body.

7. the manufacture method of glass plate according to claim 1 and 2, wherein,

Described glass plate is the glass plate of flat-panel monitor.

8. the manufacture method of glass plate according to claim 1 and 2, wherein,

The devitrification temperature of the glass that described glass plate adopts is 1050 DEG C ~ 1250 DEG C.

9. the manufacture method of glass plate according to claim 1 and 2, wherein,

Described glass plate contains respectively: the CaO of the Al2O3 of the SiO2 of 50 ~ 70 mass percents, the B2O3 of 0 ~ 15 mass percent, 5 ~ 25 mass percents, the MgO of 0 ~ 10 mass percent, 0 ~ 20 mass percent, the SrO of 0 ~ 20 mass percent, the BaO of 0 ~ 10 mass percent, the RO of 5 ~ 20 mass percents, wherein at least one composition of R contained by that select from Mg, Ca, Sr and Ba, described glass plate.

10. the manufacture method of glass plate according to claim 1 and 2, wherein,

The strain point of the glass that described glass plate adopts is more than 675 DEG C.

11. 1 kinds of device for producing glass sheets, this device for producing glass sheet is the device for producing glass sheet adopting glass tube down-drawing, in described glass tube down-drawing, the melten glass of inflow formed body is overflowed from described formed body, then the melten glass overflowed described in making collaborates in the bottom of described formed body, be configured as sheet glass thus, the feature of described device for producing glass sheet is

This device for producing glass sheet possesses:

Support unit, described support unit supports the two side ends on a direction of described formed body;

Heat riser, described heat riser makes the temperature of the periphery of described formed body;

Pressue device, described pressue device presses described formed body from least one party of the described two side ends of described formed body across described support unit; And

Control part, described control part controls, make utilize described heat riser make the temperature of the periphery of described formed body before utilize described pressue device to carry out described formed body pressing,

Described heat riser is configured with multiple near formed body, and the surface temperature of formed body is heated up equably,

Described peripheral temperature comprises the atmosphere temperature in the space being surrounded as body.