WO2014185129A1

WO2014185129A1 - Method for molding glass plate, device for manufacturing glass plate, and method for manufacturing glass plate

Info

Publication number: WO2014185129A1
Application number: PCT/JP2014/056038
Authority: WO
Inventors: 海郡司; 信之伴
Original assignee: 旭硝子株式会社
Priority date: 2013-05-16
Filing date: 2014-03-07
Publication date: 2014-11-20
Also published as: JP2016135716A

Abstract

Provided is a method for molding a glass plate that includes a step in which contraction in the width direction of a strip-shaped glass ribbon is minimized, and wherein: a support roller is provided that supports a glass ribbon in an area in which the glass ribbon has a viscosity in the range of 10.^6.7-10^7.65 dPa·s; the support roller comprises a rotating member on the tip section thereof that comes into contact with the glass ribbon; the rotating member is provided with a main body section and a plurality of protruding sections that are arranged along the outer periphery of the main body section; and at least the protruding sections of the rotating member are formed from tool steel.

Description

Glass plate forming method, glass plate manufacturing apparatus, and glass plate manufacturing method

The present invention relates to a glass plate forming method, a glass plate manufacturing apparatus, and a glass plate manufacturing method.

The float method is widely used as a glass plate forming method. The float method is a method in which molten glass introduced on a molten metal (for example, molten tin) accommodated in a bathtub is caused to flow in a predetermined direction to form a strip-shaped glass ribbon. The glass ribbon is gradually cooled in the process of flowing in the horizontal direction, then pulled up from the molten metal by a lift-out roll, and gradually cooled in a slow cooling furnace to become a sheet glass. The plate-like glass is unloaded from the slow cooling furnace and then cut into a predetermined size and shape by a cutting machine to become a glass plate as a product.

As another molding method, a fusion method is also known. In the fusion method, the molten glass overflowing from the upper left and right edges of the bowl-shaped member is allowed to flow along the left and right sides of the bowl-shaped member, and is joined at the lower edge that is the intersection of the left and right sides. This is a method of forming a plate-like glass ribbon. The glass ribbon is gradually cooled while moving downward in the vertical direction to form a sheet glass. The plate-like glass is cut into a predetermined dimensional shape by a cutting machine to become a glass plate as a product.

By the way, the glass ribbon in a state thinner than the equilibrium thickness tends to shrink in the width direction. If the shrinkage is excessive, the thickness of the product glass plate becomes thicker than the target thickness.

Therefore, conventionally, in order to suppress shrinkage in the width direction of the glass ribbon, a support roll for supporting the glass ribbon has been used (for example, see Patent Document 1). A plurality of pairs of support rolls are arranged on both sides of the glass ribbon in the width direction, and tension is applied to the glass ribbon in the width direction. The support roll has a rotating member in contact with the surface of the glass ribbon at the tip. As the rotating member rotates, the glass ribbon is sent out in a predetermined direction. The glass ribbon is gradually cooled and hardened while moving in a predetermined direction.

The rotating member of the support roll has a disk shape, for example, and has gear-shaped uneven portions on the outer periphery. As the convex portions of the concave and convex portions bite into the glass ribbon, the shrinkage of the glass ribbon is suppressed.

JP 2011-225386 A

The support roll is provided in a float bath forming region (for example, a region where the glass ribbon has a viscosity range of 10 ^4.5 to 10 ^7.5 dPa · s). In recent years, glass plates, particularly glass plates for display substrates, are required to have high quality. Moreover, the glass plate for display substrates is also required to be thin (for example, a thickness of 0.5 mm or less).

Conventional rotating members are mainly composed of stainless steel (steel material represented by SUS in Japanese Industrial Standards (JIS)) or carbon steel (steel material represented by SC in Japanese Industrial Standards (JIS)). The tip of the protrusion that bites into the ribbon is easily deformed.

In particular, the glass ribbon in the low-temperature region of the float bath (the region where the glass ribbon has a viscosity range of 10 ^6.7 to 10 ^7.65 dPa · s) is hard and difficult to grip with the rotating member. For this reason, the glass ribbon may shrink in the width direction, and a wavy deformation may occur in the glass ribbon.

This invention was made in view of the said subject, Comprising: It aims at provision of the shaping | molding method of a glass plate which can improve the wavy deformation | transformation of a glass ribbon.

In order to solve the above problems, according to one aspect of the present invention,
A method for forming a glass plate, comprising a step of suppressing the shrinkage in the width direction of a belt-like glass ribbon,
A support roll for supporting the glass ribbon in a viscosity range of 10 ^6.7 to 10 ^7.65 dPa · s is provided;
The support roll has a rotating member in contact with the glass ribbon at the tip,
The said rotating member is provided with the main-body part and the some convex part provided along the outer periphery of this main-body part, and the shaping | molding method of the glass plate by which at least the said convex part is formed with tool steel among the said rotating members. Provided.

According to one aspect of the present invention, a glass plate forming method that can improve the wave-like deformation of the glass ribbon can be provided.

1 is a partial cross-sectional view showing a glass sheet forming apparatus according to an embodiment of the present invention. FIG. 2 is a cross-sectional view taken along line II-II in FIG. It is a front view which shows the support roll by one Embodiment of this invention. FIG. 4 is a partially enlarged view of a cross section taken along line IV-IV in FIG. 3. It is a figure which shows the cross section of the taper-shaped part of the convex part of a rotation member. It is a figure which shows the pitch and height of the convex part of a rotation member.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the following drawings, the same or corresponding components are denoted by the same or corresponding reference numerals, and description thereof is omitted.

(Glass plate molding apparatus and molding method)
FIG. 1 is a partial cross-sectional view showing a glass sheet forming apparatus according to an embodiment of the present invention. FIG. 2 is a sectional view taken along line II-II in FIG. In FIG. 2, the forming area of the float bath 20 (the glass ribbon G has a viscosity range of 10 ^4.5 to 10 ^7.5 dPa · s) is A, and the first low temperature area of the float bath 20 (the glass ribbon G is 10). ^6.7 to 10 ^7.65 dPa · s) and B ′ is the second low temperature region of the float bath 20 (the glass ribbon G has a viscosity range of more than 10 ^7.5 to 10 ^7.65 dPa · s). It shows with. The molding area A and the first low temperature area B partially overlap. The second low temperature region B ′ is included in the first low temperature region B, but does not overlap with the molding region A.

The glass plate forming apparatus 10 has a float bath 20. The float bath 20 is connected to the bathtub 22 that houses the molten metal (for example, molten tin) S, the side wall 24 that is installed along the outer peripheral upper edge of the bathtub 22, and the ceiling 26 that covers the upper side of the bathtub 22. Etc. The ceiling 26 is provided with a gas supply path 30 for supplying a reducing gas in a space 28 formed between the bathtub 22 and the ceiling 26. Further, a heater 32 as a heating source is inserted into the gas supply path 30, and a heat generating portion 32 a of the heater 32 is disposed above the molten tin S and the glass ribbon G.

The forming method using the forming apparatus 10 is a method for forming a ribbon glass ribbon G by causing molten glass introduced on a molten metal (for example, molten tin) S to flow in a predetermined direction. The glass ribbon G is cooled in the process of flowing in a predetermined direction (X direction in FIG. 2), then pulled up from the molten tin S by a lift-out roll, and gradually cooled in a slow cooling furnace to become a sheet glass. The plate-like glass is unloaded from the slow cooling furnace and then cut into a predetermined size and shape by a cutting machine to become a glass plate as a product.

The space 28 in the float bath 20 is filled with a reducing gas supplied from the gas supply path 30 in order to prevent the molten tin S from being oxidized. The reducing gas contains, for example, 1 to 15% by volume of hydrogen gas and 85 to 99% by volume of nitrogen gas. The space 28 in the float bath 20 is set to a pressure higher than the atmospheric pressure in order to prevent air from entering through the gaps between the side walls 24 and the like.

In order to adjust the temperature distribution in the float bath 20, a plurality of heaters 32 are provided at intervals in the flow direction (X direction) and the width direction (Y direction) of the glass ribbon G, for example, and arranged in a matrix. Yes. The output of the heater 32 is controlled so that the temperature of the glass ribbon G becomes higher toward the upstream side in the flow direction (X direction) of the glass ribbon G. The output of the heater 32 is controlled so that the thickness of the glass ribbon G is uniform in the width direction (Y direction).

Also, the glass plate forming apparatus 10 includes a support roll 40 that supports the glass ribbon G in order to suppress the glass ribbon G in the float bath 20 from shrinking in the width direction. As shown in FIG. 2, a plurality of pairs of support rolls 40 are arranged on both sides in the width direction of the glass ribbon G, and tension is applied to the glass ribbon G in the width direction (Y direction in the figure).

The support roll 40 has a rotating member 50 in contact with the glass ribbon G at the tip. The rotating member 50 bites into the upper surface of the glass ribbon G, and supports the end in the width direction of the glass ribbon G so that the glass ribbon G does not contract in the width direction. As the rotating member 50 rotates, the glass ribbon G is sent out in a predetermined direction.

(Support roll)
FIG. 3 is a front view showing a support roll according to an embodiment of the present invention. 4 is a partially enlarged view of a cross section taken along line IV-IV in FIG. FIG. 5 is a view showing a cross section of the tapered portion of the convex portion of the rotating member. FIG. 6 is a diagram showing the pitch and height of the convex portions of the rotating member.

The support roll 40 is mainly composed of a rotating member 50, a connecting member 60, and a shaft member 70.

The shaft member 70 has a refrigerant flow path therein and is cooled by the refrigerant flowing through the refrigerant flow path, and is made of stainless steel (steel material represented by SUS in Japanese Industrial Standards (JIS)) or carbon steel (Japanese Industrial Standards). It may be formed of a metal material such as (a steel material represented by SC in (JIS)). A heat insulating material or the like may be wound around the outer periphery of the shaft member 70.

The shaft member 70 is, for example, a double pipe, and includes an inner pipe and an outer pipe. A refrigerant flow path is constituted by the inner space of the inner tube and the space formed between the outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube.

As the refrigerant, a liquid such as water or a gas such as air is used. The refrigerant passes through the inner space of the inner tube, passes through the space formed between the outer peripheral surface of the inner tube and the inner peripheral surface of the outer tube, after being supplied to the inner space of the connecting member 60 and the rotating member 50, It is discharged outside. The refrigerant discharged to the outside may be cooled by a cooler and returned to the inner space of the inner pipe again. Note that the flow direction of the refrigerant may be in the opposite direction.

As shown in FIG. 1, the shaft member 70 passes through the side wall 24, and is connected to a drive device 34 constituted by a motor, a speed reducer, and the like outside the float bath 20. When the driving device 34 is operated, the shaft member 70, the connecting member 60, and the rotating member 50 rotate integrally around the central axis of the shaft member 70.

The connecting member 60 is a member that connects the shaft member 70 and the rotating member 50. The connecting member 60 has an inner space communicating with the refrigerant flow path of the shaft member 70 therein. The connecting member 60 is, for example, cylindrical, and the outer diameter and inner diameter of the end of the connecting member 60 on the shaft member 70 side are the same as the outer diameter and inner diameter of the outer tube of the shaft member 70, respectively. The connecting member 60 is abutted against the outer tube of the shaft member 70, and is connected coaxially, for example, by welding. The connecting member 60 is preferably made of a material that can be easily welded to the shaft member 70, and more preferably formed of the same material.

(Rotating member)
As shown in FIG. 3, the rotating member 50 has a disk shape, and the central axis of the rotating member 50 and the central axis of the shaft member 70 are on the same straight line.

As shown in FIG. 1, the rotating member 50 is in contact with the surface of the glass ribbon G (in this embodiment, the upper surface) at the outer periphery. As the rotating member 50 rotates, the glass ribbon G is sent out in a predetermined direction.

As shown in FIG. 4, the rotating member 50 has an inner space 51 as a refrigerant flow path. The inner space 51 communicates with the inner space of the connecting member 60 through an opening formed on the back side of the rotating member 50.

As shown in FIG. 3, the rotating member 50 integrally includes a disk-shaped main body 53 and a plurality of convex portions 54 provided along the outer periphery of the main body 53. The plurality of convex portions 54 are provided at equal intervals in the circumferential direction.

The shape of each convex portion 54 may be a tapered shape (for example, a quadrangular pyramid shape) so as to easily bite into the glass ribbon G.

The angle A or B (see FIG. 5) of the tapered portion of the convex portion 54 with respect to the surface perpendicular to the shaft member 70 is preferably 45 ° or less, more preferably 30 ° or less in consideration of the grip force with respect to the glass ribbon G. More preferably 25 ° or less. In consideration of the strength of the tapered portion, the angle A or B is preferably 15 ° or more.

The width C (see FIG. 5) of the tip portion of the tapered portion of the convex portion 54 is preferably 2 mm or less, more preferably 1 mm or less, and further preferably 0.5 mm or less in consideration of the grip force with respect to the glass ribbon G. The tip portion does not necessarily have to be linear, and may have a curved shape or a composite shape.

The pitch D of the convex portions 54 (see FIG. 6) is preferably 6.5 mm or less, and more preferably 5.5 mm or less in consideration of the grip force with respect to the glass ribbon G. In consideration of the strength and workability of the tapered portion, the pitch D is preferably 1.5 mm or more, and more preferably 2.5 mm or more.

The height E of the convex portion 54 (see FIG. 6) is preferably 4 mm or more, and more preferably 5 mm or more in consideration of the grip force with respect to the glass ribbon G. In consideration of the strength and workability of the tapered portion, the height E is preferably 8 mm or less, and more preferably 7 mm or less.

3 are formed in two rows (see FIG. 4) in the thickness direction (Y direction in FIG. 1) of the outer periphery of the main body 53, but may be formed in three or more rows. Only rows may be formed.

The radius of the rotating member 50 is preferably 100 mm or more, more preferably 150 mm or more, still more preferably 180 mm or more, considering contact prevention between the connecting member 60 and the glass ribbon G and the horizontality of the shaft member 70. Considering position adjustment with the glass ribbon G and fine adjustment of the rotation speed of the rotating member 50, 350 mm or less is preferable, 300 mm or less is more preferable, and 270 mm or less is more preferable.

At least the convex portion 54 of the rotating member 50 is formed of tool steel, preferably hot die steel. In the present embodiment, the main body 53 is also made of tool steel.

Here, “hot die steel” means “hot mold” alloy tool steel among “SKD” described in JIS G4404.

The tool steel is not particularly limited, and for example, steel materials represented by SKS, SKD, SKT, and SKH in Japanese Industrial Standard (JIS) can be used. Examples of tool steel include SKS4, SKS41, SKS42, SKS43, SKS44, SKS1, SKS11, SKS2, SK21, SKS5, SKS51, SKS7, SKS8, SKS3, SKS31, SKS93, SKD1, SKD11, SKD11, SKD11, SKD11, SKD11 SKD6, SKD61, SKT1, SKT2, SKT3, SKT4, SKT5, SKT6, SKH2, SKH3, SKH4A, SKH4B, SKH40, SKH5, SKH51, SKH52, SKH53, HSK58, S The steel developed by each company improved from these grades can be used. Such a developed steel is mainly composed of Fe, and preferably has a C content of 0.3 to 2.5% by mass, a Si content of 0 to 1.1% by mass, and a Mn content of 0 to 1.1 mass%, Ni content 0-2.0 mass%, Cr content 0-13.5 mass%, Mo content 0-5.0 mass%, V content The content is 0 to 4.0 mass%, the W content is 0 to 10.0 mass%, and the Co content is 0 to 10.0 mass%. The hot die steel is not particularly limited, and SKD61 and improved steel materials of various companies can be used. Such hot die steel has Fe as a main component, preferably C content of 0.3 to 0.5% by mass, Si content of 0.3 to 1.20% by mass, Mn content The amount is 0.4 to 0.9% by mass, the Ni content is 0 to 1.8% by mass, the Cr content is 1.3 to 5.50% by mass, and the Mo content is 0.4 to 2%. 0.7% by mass and the V content is 0.2 to 1.7% by mass. From the viewpoint of workability and cost, the hot die steel is preferably SKD61. SKD61 is mainly composed of Fe, and has a C content of 0.35 to 0.42 mass% and a Si content of 0.80 to 1.20, as defined in Japanese Industrial Standards (JIS). Mass%, Mn content 0.25 to 0.50 mass%, P content 0 to 0.030 mass%, S content 0 to 0.020 mass%, Cr content 4 .80 to 5.50 mass%, steel content of Mo 1.00 to 1.50 mass%, V content 0.80 to 1.15 mass%, inevitably contained impurities May further be included. SKD61 may be expressed as X40CrMoV5-1 in the international standard (ISO 4957: 1999).

Since tool steel has high temperature strength compared to conventional materials such as SUS and SC, the deformation of the convex portion 54 that bites into the glass ribbon G can be suppressed, and the durability of the rotating member 50 can be improved. Moreover, since tool steel has high temperature strength compared with conventional materials, such as SUS and SC, the convex part 54 can be sharpened so that the convex part 54 may bite into the glass ribbon G easily. Therefore, the glass ribbon G is rotated in the first low temperature region B (the glass ribbon G has a viscosity range of 10 ^6.7 to ^10.7.65 dPa · s) of the float bath 20 that has been difficult to grip. 50 can be gripped, and the occurrence of wavy deformation of the glass ribbon G can be reduced. Therefore, the flatness of the glass plate can be improved.

Here, the temperature of the glass ribbon G is represented by the temperature at the center in the width direction of the glass ribbon G. The temperature of the glass ribbon G is measured by, for example, a radiation thermometer. When the glass type is alkali-free glass, the temperature range corresponding to the viscosity range of 10 ^6.7 to ^10.7.65 dPa · s is 937 to 1000 ° C.

The glass ribbon G is supported in the second low temperature range B ′ (range of 937 ° C. or more and less than 946 ° C. in the case of non-alkali glass) having a viscosity range of more than 10 ^7.5 to 10 ^7.65 dPa · s. It is preferably supported by the roll 40.

The glass ribbon G in the present embodiment, in the region viscosity is less than 10 ^{6.7 dPa} · s of the glass ribbon G, but is supported by the supporting roll 40 may be supported by a conventional support roll. In a region where the viscosity of the glass ribbon G is less than 10 ^6.7 dPa · s, the glass ribbon G can be gripped by a conventional rotating member.

Rotating member 50 may have a protective film 55 with excellent corrosion resistance on at least a part of the outer surface, as shown in FIG. In particular, it is preferable to have a protective film 55 containing chromium nitride or metallic chromium. Since chromium nitride and metallic chromium have higher corrosion resistance against the splash and vapor of molten tin S than hot die steel, the tin resistance of the rotating member 50 can be improved.

The protective film 55 covers the outer surface of the convex portion 54 and covers a part of the outer surface of the main body portion 53.

Examples of the method for forming the protective film 55 include a plating method, a vapor deposition method, a sputtering method, a CVD method, an ion coating method, a thermal spraying method, and the like, which are appropriately selected according to the shape of the convex portion 54 and the like. For example, when sharpening the convex portion 54, a dry coating method such as an evaporation method, a sputtering method, or an ion coating method is preferable.

Rotating member 50 is integrated with connecting member 60 by welding or the like and supplied as one component. If the parts are stocked in the factory where the molding apparatus 10 is installed, the support roll 40 can be repaired by replacing the parts when the convex portion 54 is deformed. This repair is performed by cutting the welded portion between the connecting member 60 and the shaft member 70 and exchanging the above parts, and then welding the connecting member 60 and the outer tube of the shaft member 70. The shaft member 70 may be reused and repeatedly used when the parts are replaced.

The glass plate as a product is not particularly limited, but may be for a flat panel display (FPD) such as a liquid crystal display (LCD), a plasma display (PDP), or an organic EL display. In recent years, thinning of FPDs has progressed, and thinning of glass plates for FPDs has progressed. In particular, in the case of a glass plate for a display substrate, a glass plate of 0.7 mm or less, more preferably 0.3 mm or less, more preferably 0.2 mm or less, particularly preferably 0.1 mm or less is desired. Therefore, the thickness of the glass ribbon G is reduced, the shrinkage force in the width direction of the glass ribbon G is increased, and the molding temperature of the glass ribbon G is increased. As described above, the support roll 40 of the present embodiment has a high high-temperature strength of the convex portion 54 that bites into the glass ribbon G, and since the convex portion 54 can be sharpened, it can be used for forming a glass plate for FPD. Is suitable.

The kind of glass plate which is a product is not particularly limited. The composition of the glass plate is, for example, expressed by mass% based on oxide, SiO ₂ : 50% to 75%, Al ₂ O ₃ : 0.1 to 24%, B ₂ O ₃ : 0 to 12%, MgO: 0 to 10%, CaO: 0 to 14.5%, SrO: 0 to 24%, BaO: 0 to 13.5%, Na ₂ O: 0 to 20%, K ₂ O: 0 to 20%, ZrO ₂ : 0-5%, MgO + CaO + SrO + BaO: 5-29.5%, Na ₂ O + K ₂ O: 0-20%.

The glass plate may be formed of non-alkali glass, for example. The alkali-free glass is a glass that does not substantially contain an alkali metal oxide (Na ₂ O, K ₂ O, Li ₂ O). The total content (Na ₂ O + K ₂ O + Li ₂ O) of the alkali metal oxide content in the alkali-free glass may be, for example, 0.1% or less.

The alkali-free glass is, for example, expressed in terms of mass percentage based on oxide, SiO ₂ : 50 to 73%, preferably 50 to 66%, Al ₂ O ₃ : 10.5 to 24%, B ₂ O ₃ : 0 to 12%, MgO: 0 to 10%, preferably 0 to 8%, CaO: 0 to 14.5%, SrO: 0 to 24%, BaO: 0 to 13.5%, ZrO ₂ : 0 to 5% MgO + CaO + SrO + BaO: 8 to 29.5%, preferably 9 to 29.5%.

The alkali-free glass has a high strain point, and when considering the solubility, it is preferably expressed in terms of mass percentage based on oxide, SiO ₂ : 58 to 66%, Al ₂ O ₃ : 15 to 22%, B ₂ O ₃ : 5 to 12%, MgO: 0 to 8%, CaO: 0 to 9%, SrO: 3 to 12.5%, BaO: 0 to 2%, MgO + CaO + SrO + BaO: 9 to 18% is there.

When considering the high strain point, the alkali-free glass is preferably expressed in terms of mass percentage based on oxide, SiO ₂ : 54 to 73%, Al ₂ O ₃ : 10.5 to 22.5%, B ₂ O ₃ : 0 to 5.5%, MgO: 0 to 10%, CaO: 0 to 9%, SrO: 0 to 16%, BaO: 0 to 2.5%, MgO + CaO + SrO + BaO: 8 to 26% is there.

In Example 1, the support roll shown in FIGS. 3 and 4 was brought into contact with the glass ribbon in the float bath, and the presence or absence of deformation of the convex portion that bite into the glass ribbon was examined.

As the rotating member of the support roll, a main body part and a convex part having SKD61 (manufactured by Hitachi Metals, DAC) were used. The strength of SKD61 used was a Rockwell hardness (HRC) of 30-40. A chromium nitride protective film was formed on the surface by dry coating.

The presence or absence of the deformation of the convex portion was visually confirmed after the glass ribbon and the rotating member were continuously contacted for 100 hours at a temperature (980 ° C.) corresponding to a viscosity of 10 ⁷ dPa · s. As a result, in Example 1, no deformation of the convex portion was observed.

On the other hand, in Comparative Example 1, the test was performed under the same conditions as in Example 1 except that the main body portion and the convex portion of the rotating member were composed of S25C instead of SKD61.

As a result of the test, in Comparative Example 1, the tip of the convex portion was bent, and deformation of the convex portion was recognized.

Thereby, according to Example 1, it was confirmed that the support roll excellent in durability can be provided.

As mentioned above, although embodiment of the manufacturing method of a glass plate and the manufacturing apparatus of a glass plate was demonstrated, this invention is not limited to the said embodiment. The present invention can be modified and improved within the scope of the gist of the claims.

For example, the support roll 40 of the above embodiment is used in the float method, but may be used in other forming methods, for example, the fusion method.

In the fusion method, the rotating members of the support roll are columnar or cylindrical, and are used in pairs so as to sandwich the glass ribbon from the front side and the back side. A plurality of pairs of support rolls composed of two support rolls are arranged on both sides of the glass ribbon in the width direction.

In the case of the fusion method, the glass plate forming apparatus has a bowl-shaped member to which molten glass is continuously supplied. The molten glass overflowing from the upper edges of the left and right sides of the bowl-shaped member flows down along the left and right sides of the bowl-shaped member, and merges at the lower edge where the left and right sides meet, and is integrated with the glass ribbon. Become. The glass ribbon is fed downward while being supported by a plurality of pairs of support rolls.

The rotating member 50 of the above embodiment has the protective film 55, but may not have the protective film 55.

Although the inner tube of the shaft member 70 of the above embodiment is arranged inside the outer tube, it may extend to the inside of the connecting member 60 or the inside of the rotating member 50. When extended, the flow of the refrigerant in the inner space of the connecting member 60 or the inner space 51 of the rotating member 50 is rectified, and the cooling efficiency of the connecting member 60 and the rotating member 50 is increased.

This application claims priority based on Japanese Patent Application No. 2013-104381 filed with the Japan Patent Office on May 16, 2013. The entire contents of Japanese Patent Application No. 2013-104381 are incorporated herein by reference. To do.

DESCRIPTION OF SYMBOLS 10 Glass plate shaping | molding apparatus 20 Float bath 40 Support roll 50 Rotating member 53 Main-body part 54 Convex part 55 Protective film G Glass ribbon

Claims

A method for forming a glass plate, comprising a step of suppressing the shrinkage in the width direction of a belt-like glass ribbon,
A support roll for supporting the glass ribbon in a viscosity range of 10 6.7 to 10 7.65 dPa · s is provided;
The support roll has a rotating member in contact with the glass ribbon at the tip,
The said rotation member is provided with the main-body part and the some convex part provided along the outer periphery of this main-body part, The molding method of the glass plate by which at least the said convex part is formed with tool steel among the said rotation members.
The method for forming a glass sheet according to claim 1, wherein the tool steel is hot die steel.
The method for forming a glass plate according to claim 2, wherein the hot die steel is SKD61.
The method of forming a glass plate according to claim 3, wherein the rotating member has a protective film containing chromium nitride or metallic chromium on at least a part of the outer surface.
The method for forming a glass plate according to any one of claims 1 to 4, wherein the shape of the rotating member is a disk shape.
A belt-shaped glass ribbon comprising a support roll that supports the glass ribbon in a viscosity range of 10 6.7 to 10 7.65 dPa · s;
The support roll has a rotating member in contact with the glass ribbon at the tip,
The said rotation member is provided with the main-body part and the some convex part provided along the outer periphery of this main-body part, The shaping | molding apparatus of the glass plate by which at least the said convex part is formed with tool steel among the said rotation members.
The glass plate forming apparatus according to claim 6, wherein the tool steel is hot die steel.
The glass plate forming apparatus according to claim 7, wherein the hot die steel is SKD61.
The said rotation member is a glass plate shaping | molding apparatus of Claim 8 which has a protective film containing chromium nitride or metal chromium in at least one part of an outer surface.
The glass plate forming apparatus according to any one of claims 6 to 9, wherein a shape of the rotating member is a disk shape.
A method for producing a glass plate, comprising a step of gradually cooling and cutting a band-shaped glass ribbon obtained by the method for forming a glass plate according to any one of claims 1 to 5.