Specific embodiment
Hereinafter, with reference to attached drawing, description of specific embodiments of the present invention.In the drawings, to identical or corresponding
Composition assign it is identical or it is corresponding label and omit the description.
(overview of float glass manufacturing device)
Fig. 1 is the cross-sectional view of float glass manufacturing device according to one embodiment.Fig. 2 is the II-II line along Fig. 1
Float glass manufacturing device cross-sectional view.The diagram of upper roller 60 shown in Fig. 3 is omitted in fig. 1 and 2.Fig. 3 is to indicate
The top view of bath according to one embodiment, glass tape and upper roller.In the drawings, X-direction is the flowing of glass tape 6
Direction, Y-direction are the width direction of glass tape 6, and Z-direction is vertical direction.X-direction, Y-direction and Z-direction are perpendicular to one another
Direction.
Float glass manufacturing device 10 has bath 20, and the bath 20 accommodates the molten metal for floating melten glass 4
2.For molten metal 2, molten tin or molten tin alloy are typically used.Melten glass 4 is continually fed into appearance
It is contained on the molten metal 2 in bath 20, and be shaped as while downstream being flowed on molten metal 2 from upstream side
The glass tape 6 of plate.Glass tape 6 is gradually cooled while flowing on the liquid level of molten metal 2 along the direction arrow A and is become
Firmly.Glass tape 6 is raised from molten metal 2 in the downstream area of bath 20, is sent to leer.By will be in leer
Glass tape 6 after Slow cooling is cut into predetermined size, produces glass plate (float glass).
Float glass manufacturing device 10 include be arranged in the top plate 30 of the top of bath 20, be suspended on it is more on top plate 30
Multiple controllers 50 of a heater 40 and the multiple heaters 40 of control.Control of multiple heaters 40 in multiple controllers 50
Under system, the glass tape 6 passed through from below is heated.For each heater 40, such as use progress electrified regulation
Electric heater.The shape of each heater 40 is not particularly limited, such as can be rodlike.By the hair for controlling each heater 40
Heat controls the Temperature Distribution of glass tape 6.Multiple controllers 50 are the equipment for controlling the calorific value of multiple heaters 40.Each control
Device 50 processed is made of microcomputer etc..
Float glass manufacturing device 10 have multipair upper roller 60, the multipair upper roller 60 along glass tape 6 flow direction
It is separated from each other and is arranged, and support the width direction both ends of glass tape 6 (with reference to Fig. 3).Multipair upper roller 60 passes through support glass
The width direction both ends of glass band 6 and inhibit the width of glass tape 6 to narrow because of surface tension.Each upper roller 60 is by support glass tape
The discoid upper roller main body 61 of 6 width direction end and the rotary shaft 62 connecting with upper roller main body 61 are constituted.Discoid
Upper roller main body 61 is coaxially disposed with rotary shaft 62.When rotating driving rotary shaft 62 with driving devices such as motor, upper roller master
Body 61 rotates and downstream sends out glass tape 6.
(bath)
As shown in figure 3, bath 20 successively includes the width direction of bath 20 from downstream having a size of constant to the upstream side
Narrow region A1, bath 20 width direction size be gradually increased intermediate region A2, bath 20 width direction size be greater than it is narrow
Region A1 and be constant wide region A3.The X-direction size X1 of wide region A3 is, for example, the molten metal 2 being contained in bath 20
X-direction size X0 30% or more and 80% or less.
Multipair upper roller 60 supports the width direction both ends of glass tape 6 in wide region A3.It will be from a pair of most upstream
The contact position of roller 60 and glass tape 6 plays the region until a pair of of upper roller 60 of most downstream and the contact position of glass tape 6
Referred to as shaped region A4.In shaped region A4, the viscosity at the width direction center (Y-direction center) of glass tape 6 is, for example,
104.5DPas or more and 107.5DPas or less.
As shown in Fig. 2, bath 20 include the metal shell 21 of box-shaped, be positioned in metal shell 21 bottom surface and with melting
The multiple side bricks 22 and be positioned in the bottom surface of metal shell 21 and the following table face contact with molten metal 2 that the side of metal 2 contacts
Multiple bottom bricks 23.Multiple side bricks 22 are adjacent with the side of metal shell 21 and arrange, and multiple bottom bricks 23 are in multiple side bricks 22
Inside is arranged with Y-direction along the X direction.
Seam 24 is formed between adjacent bottom brick 23 in the Y direction.Seam 24 is gap.It is difficult to prevent molten metal 2 from flowing
Enter seam 24.The molten metal 2 flowed into seam 24 reaches up to the bottom surface of metal shell 21.
In order to inhibit reacting for metal shell 21 and molten metal 2, it is arranged in the lower section of metal shell 21 to metal shell
The cooling nozzles 25 of the cooling gas such as 21 lower surface blows air.Cooling nozzles 25 are along (upward) the blowing cooling in the direction arrow B
Gas.Thereby, it is possible to the temperature of metal shell 21 is reduced to the fusing point of molten metal 2 hereinafter, and being able to suppress melting gold
Category 2 is reacted with metal shell 21.
Fig. 4 is the top view for indicating the configuration of the bottom brick and side brick according to the composition bath of embodiment 1.Along the X direction and Y
Direction is configured with multiple bottom bricks 23.Multiple bottom bricks 23 by being arranged in a column along the Y direction constitute bottom brick column 26.Along the X direction
Multiple bottom brick column 26 are arranged with, form boundary line 27 between adjacent bottom brick column 26 in the X direction.It should be noted that bottom brick
The quantity of column 26 is not limited to quantity shown in Fig. 4.In addition, the quantity of the bottom brick 23 in each bottom brick column 26 is not limited to institute in Fig. 4
The quantity shown.
By the way, molten metal 2 flows into seam 24, and molten metal 2 has the thermal conductivity higher than bottom brick 23.Cause
This, compared with bottom brick 23, seam 24 is easy have the tendency for becoming low temperature by the cooling of cooling nozzles 25.Seam 24 and bottom brick
23 arrange alternately along Y-direction, therefore are formed along a y-direction temperature unevenness.
Then, in the present embodiment, at least one boundary line 27, the seam 24 of the bottom brick column 26 of upstream side is under
Swim the bottom brick column 26 of side seam 24 be provided at one more than it is discontinuous and at one more than be staggered.For example, from upstream
The place kth boundary line 27-k is played in side (in Fig. 4 be left side), from the seam 24 of k-th of the bottom brick column 26-k in upstream side and from upstream
The seam 24 of+1 bottom brick column 26-k+1 of side kth be provided at one more than it is discontinuous and at one more than be staggered.Here, k
It is 1 or more at least one natural number, such as is 1 or more and 11 random natural numbers below in Fig. 4.
In glass tape 6, the position passed through from the top of the seam 24 of the low temperature in k-th of bottom brick column 26-k is then from
The top of the bottom brick 23 of high temperature in k+1 bottom brick column 26-k+1 passes through.In addition, in glass tape 6, from k-th of bottom brick column 26-
The position that the top of the bottom brick 23 of high temperature in k passes through is then from the seam 24 of the low temperature in+1 bottom brick column 26-k+1 of kth
Top passes through.Thereby, it is possible to inhibit the temperature in the Y-direction of glass tape 6 uneven, in the Y-direction so as to reduce glass tape 6
Plate thickness it is uneven.
If the plate thickness that can be reduced in the Y-direction of glass tape 6 is uneven, plate thickness is not generated in the X-direction of glass tape 6
Unevenness, therefore the plate thickness that can reduce entire glass tape 6 is uneven.Here, for the plate thickness of the X-direction of glass tape 6 is uneven,
It is uneven different from the plate thickness of the prevailing Y-direction of pulling force generated by upper roller 60, it is generated by the conveying roller in leer
Pulling force is occupied an leading position.Therefore, if the conveying speed of the glass tape 6 in leer is constant, by the pulling force of conveying roller generation
Become constant, so that the plate thickness for not generating the X-direction of glass tape 6 is uneven.
As a result, it is possible to obtain longitudinal size be 950mm or more, lateral dimension is 1000mm or more and the plate thickness that is averaged is
It is the float glass of rectangle, the maximum value and minimum of the plate thickness in the entire surface of the float glass under 0.75mm vertical view below
Value difference be 20 μm hereinafter, and the point centered on the arbitrary point in face, the size of vertical and horizontal be 150mm just
The difference of the maxima and minima of plate thickness is 4.0 μm or less in rectangular range.Here, longitudinal size is under overlooking for rectangle
The short side direction size of float glass, lateral dimension are the longitudinal direction sizes for overlooking the lower float glass for rectangle.Vertical view is
Refer in Fig. 4 etc. from Z-direction.
In the present embodiment, at least one boundary line 27 in wide region A3, the bottom brick column 26 of upstream side are connect
Seam 24 and the seams 24 of the bottom brick column 26 in downstream side be provided at one more than discontinuously and at one more than be staggered.This be because
For compared with intermediate region A2, narrow region A1, wide region A3 is high temperature, size, the shape of glass tape 6 are carried out in wide region A3
Adjusting.In intermediate region A2, narrow region A1, the viscosity of glass tape 6 is high, and therefore, it is difficult to carry out the size of glass tape 6, shape
Adjusting.
In the present embodiment, at least one boundary line 27 in shaped region A4, the bottom brick column 26 of upstream side
Seam 24 and the seam 24 of the bottom brick column 26 in downstream side be provided at one more than it is discontinuous and at one more than be staggered.This is
Because also carrying out the adjusting of the size, shape of glass tape 6 using upper roller 60 in shaped region A4 in wide region A3.
In the present embodiment, the distance for the X-direction started from the upstream end of molten metal 2 be 0.1 × X0 or more and
At at least one boundary line 27 in 0.5 × X0 region A5 below, seam 24 and the downstream side of the bottom brick column 26 of upstream side
The seam 24 of bottom brick column 26 be provided at one more than it is discontinuous and at one more than be staggered.
For each bottom brick column 26, multiple seams 24 can be arranged to the Y-direction center line 20L of bath 20 be
The heart and line is symmetrical.Thereby, it is possible to make the Temperature Distribution of molten metal 2 and the Temperature Distribution of glass tape 6 with the Y-direction of bath 20
Centered on center line 20L and line is symmetrical.As a result, being easy to carry out the control of the plate thickness distribution of glass tape 6.
(heater)
Fig. 5 is the top view for indicating the configuration of the heater control zone according to embodiment 1.Width region A3 is illustrated in Fig. 5
In heater control zone configuration, omit intermediate region A2, heater control zone in narrow region A1 configuration figure
Show.Not only in wide region A3, heater 40 can also be set in intermediate region A2, narrow region A1.
As shown in figure 5, the heater area that multiple heaters 40 are arranged is divided into multiple heater controls in the X direction
Column 41.Each heater control column 41 are divided into multiple heater control zones 42 in the Y direction.It should be noted that heating
The quantity of device control column 41 is not limited to quantity shown in Fig. 5.In addition, the heater control zone in each heater control column 41
42 quantity is not limited to quantity shown in Fig. 5.
It is each provided with multiple heaters 40 in each heater control zone 42, utilizes a corresponding controller 50
(referring to Fig. 1) is uniformly controlled.Thereby, it is possible to reduce the quantity of controller 50.It should be noted that utilizing corresponding one
50 pairs of the controller multiple heaters 40 being arranged in a heater control zone 42 are uniformly controlled such that respective
Calorific value is roughly the same.
Two adjacent heaters control column 41 are divided by a cut-off rule 45 in the X direction.The cut-off rule 45 is located at the side X
Approximate centre between adjacent actual heater 40 upwards.On the other hand, adjacent two heater controls in the Y direction
Section 42 processed is divided by a dividing line 46.The dividing line 46 is located at big between actual heater 40 adjacent in Y-direction
Cause centre.
By the way, for heater controls column 41, two adjacent heater control zones in the Y direction
When the calorific value difference of the per unit area in section 42, temperature change sharply occurs along the Y direction near dividing line 46.
Therefore, in the present embodiment, at least one cut-off rule 45, the division of the heater control column 41 of upstream side
The dividing line 46 of the heater control column 41 in line 46 and downstream side be provided at one more than it is discontinuous and at one more than it is wrong
It opens.For example, from upstream side (in Fig. 5 be left side) at the m articles cut-off rule 45-m, m-th of heater control from upstream side
The dividing line 46 of system column 41-m and the dividing line 46 of the m+1 heater control column 41-m+1 from upstream side are provided in one
Place it is above discontinuous and at one more than be staggered.Here, at least one natural number that m is 1 or more, such as be 1 or more in Fig. 5
And 6 random natural number below.
It is logical from the lower section of the dividing line 46 of the temperature change in m-th of heater control column 41-m sharply in glass tape 6
The position crossed is then under the slow heater control zone 42 of temperature change in the m+1 heater control column 41-m+1
Side passes through.Thereby, it is possible to inhibit the temperature in the Y-direction of glass tape 6 uneven, in the Y-direction so as to reduce glass tape 6
Plate thickness is uneven.
In the present embodiment, in z-direction, at least one cut-off rule 45 in wide region A3, upstream side adds
The dividing line 46 of the heater control column 41 of the dividing line 46 and downstream side of hot device control column 41 be provided at one more than not
It is continuous and at one more than be staggered.This is because wide region A3 is high temperature, in Kuan Qu compared with intermediate region A2, narrow region A1
The adjusting of the size, shape of glass tape 6 is carried out in the A3 of domain.In intermediate region A2, narrow region A1, due to the viscosity of glass tape 6
Height, therefore, it is difficult to carry out the adjusting of the size of glass tape 6, shape.
In the present embodiment, in z-direction, at least one cut-off rule 45 in shaped region A4, upstream side
More than the dividing line 46 of the heater control column 41 of the dividing line 46 and downstream side of heater control column 41 is provided at one
It is discontinuous and at one more than be staggered.This is because also carrying out glass using upper roller 60 in shaped region A4 in wide region A3
Adjusting with 6 size, shape.
It in the present embodiment, is 0.1 × X0 or more and 0.5 in the X-direction distance started from the upstream end of molten metal 2
At at least one cut-off rule 45 in × X0 region A5 below, the dividing line 46 of the heater control column 41 of upstream side and downstream
The dividing line 46 of the heater control column 41 of side be provided at one more than it is discontinuous and at one more than be staggered.
For each heater controls column 41, multiple dividing lines 46 can be arranged to the Y-direction center with bath 20
Centered on line 20L and line is symmetrical.Thereby, it is possible to make the Temperature Distribution of molten metal 2 and the Temperature Distribution of glass tape 6 with bath
Centered on 20 Y-direction center line 20L and line is symmetrical.As a result, being easy to carry out the control of the plate thickness distribution of glass tape 6.
(float glass)
Shape under the vertical view of float glass is rectangle, longitudinal size is 950mm or more, lateral dimension be 1000mm with
The upper and plate thickness that is averaged is 0.75mm or less.The difference of the maxima and minima of plate thickness in the entire surface of float glass is 20 μm
Below.The point centered on the arbitrary point in the face of float glass is the square of 150mm in the size of vertical and horizontal
In range, the difference of the maxima and minima of plate thickness is 4.0 μm or less.If the float glass is used for FPD glass substrate,
The thickness deviation in the entire surface of FPD glass substrate can then be reduced and inhibited in the close limit of FPD glass substrate
The change dramatically of plate thickness is able to suppress defocusing for exposure device.It should be noted that including for the float glass of rectangle under overlooking
Float glass after carrying out grinding with grinding stone diagonal section using corner cut.The grinding part is known as corner cut portion, corner cut
The size in portion is, for example, a few mm.
The difference of the maxima and minima of plate thickness in the entire surface of float glass is preferably 10 μm or less.
The average plate thickness of float glass is preferably 0.45mm or less.
Float glass is preferably longitudinally having a size of 1700mm or more and lateral dimension is 2000mm or more.
Float glass is for example made of alkali-free glass, indicates that the alkali-free glass contains with the quality % of oxide benchmark:
SiO2: 54%~66%, Al2O3: 10%~23%, B2O3: 0%~12%, MgO:0%~12%, CaO:0%~15%,
SrO:0%~16%, BaO:0%~15% and MgO+CaO+SrO+BaO:8%~26%.Here, " MgO+CaO+SrO+
BaO " refers to the total content of MgO, CaO, SrO and BaO.In addition, " alkali-free glass " refers to Li2O、Na2O and K2The alkali metal such as O
The total content of oxide is less than 0.1 mass %.It is indicated with the quality % of oxide benchmark, the preferred B of alkali-free glass2O3Content be
5% or less.
Embodiment
Hereinafter, further illustrating the present invention using embodiment and comparative example.It should be noted that the present invention is not restricted to these
It records.It is longitudinal to correspond to X-direction in embodiment 1 and comparative example 1, laterally correspond to Y-direction.
[embodiment 1]
In embodiment 1, using with bottom brick shown in Fig. 4 configuration and Fig. 5 shown in heater control zone
The float glass manufacturing device of the configuration of section manufactures glass tape, and it is 1000mm that lateral dimension has been cut out from the glass tape produced
Float glass and lateral dimension be 2000mm float glass.Float glass is made of alkali-free glass, with oxide benchmark
Quality % indicates that the alkali-free glass contains: SiO2: 60%, Al2O3: 17%, B2O3: 8%, MgO:3%, CaO:4%, SrO:
8%, BaO:0%, MgO+CaO+SrO+BaO:15%.
The float glass that lateral dimension is 1000mm has been cut out from region Y1 shown in Fig. 3~Fig. 5.It will be obtained
The plate thickness distribution of float glass is shown in Fig. 6.In Fig. 6, the longitudinal axis is plate thickness, and horizontal axis is the width direction center line from glass tape 6
The distance that 6L is started.For the distance, the downside in Fig. 3 is indicated to be negative, and the upside in Fig. 3 is indicated to be positive.
As shown in fig. 6, the average plate thickness for the float glass that the lateral dimension obtained in embodiment 1 is 1000mm is
0.50mm, whole thickness deviation are 3.3 μm, and the thickness deviation in the range of arbitrary 150mm is 4.0 μm or less.From Y-direction
Thickness deviation in the range of position 0mm is played until the 150mm of Y-direction position is 1.0 μm.
In addition, having cut out the float glass that lateral dimension is 2000mm from region Y2 shown in Fig. 3~Fig. 5.By institute
The plate thickness distribution of obtained float glass is shown in Fig. 7.In Fig. 7, the longitudinal axis is plate thickness, and horizontal axis is the width direction from glass tape 6
The distance that center line 6L is started.For the distance, the downside in Fig. 3 is indicated to be negative, and the upside in Fig. 3 is indicated
It is positive.
As shown in fig. 7, the average plate thickness for the float glass that the lateral dimension obtained in embodiment 1 is 2000mm is
0.50mm, whole thickness deviation are 3.3 μm, and the thickness deviation in the range of arbitrary 150mm is 4.0 μm or less.From Y-direction
Thickness deviation in the range of position 0mm is played until the 150mm of Y-direction position is 3.3 μm.
[comparative example 1]
Fig. 8 is the top view for indicating the configuration of the bottom brick and side brick according to the bath of comparative example 1.In comparative example 1, use
The configuration of bottom brick shown in fig. 8 replaces the configuration of bottom brick shown in Fig. 4.In addition to this, in item same as Example 1
The float glass that lateral dimension is 1000mm and the float glass that lateral dimension is 2000mm have been manufactured under part.
The float glass that lateral dimension is 1000mm has been cut out from Fig. 3, Fig. 5, region Y1 shown in fig. 8.By gained
To float glass plate thickness distribution be shown in Fig. 6.
As shown in fig. 6, the average plate thickness for the float glass that the lateral dimension obtained in comparative example 1 is 1000mm is
0.51mm, whole thickness deviation are 5.2 μm, the plate in the range of 0mm is played until the 150mm of Y-direction position from Y-direction position
Thick deviation is 4.6 μm.
In addition, having cut out the float glass that lateral dimension is 2000mm from Fig. 3, Fig. 5, region Y2 shown in fig. 8.It will
The plate thickness distribution of obtained float glass is shown in Fig. 7.
As shown in fig. 7, the average plate thickness for the float glass that the lateral dimension obtained in comparative example 1 is 2000mm is
0.51mm, whole thickness deviation are 11 μm, the plate in the range of 0mm is played until the 150mm of Y-direction position from Y-direction position
Thick deviation is 4.6 μm.
[summary]
Compared with using the comparative example 1 of configuration of bottom brick shown in Fig. 8, in the configuration for using bottom brick shown in Fig. 4
Embodiment 1 in whole thickness deviation it is small, the thickness deviation in the range of arbitrary 150mm is small.By at least one
At boundary line 27 by the seam 24 of the seam 24 of the bottom brick column 26 of upstream side and the bottom brick column 26 in downstream side be arranged at one with
It is upper discontinuous and at one more than be staggered, the temperature being able to suppress in the Y-direction of glass tape 6 is uneven, so as to reduce glass
Plate thickness in Y-direction with 6 is uneven.
More than, the embodiment of float glass manufacturing device, float glass making process and float glass etc. is carried out
Explanation, but the present invention is not limited to the above embodiments, the model for the purport of the invention that can be recorded in detail in the claims
Enclose interior progress various modifications, improvement.