JP5589824B2 - Glass plate manufacturing method, glass plate manufacturing apparatus and glass roll - Google Patents

Description

  The present invention relates to a glass plate manufacturing method, a glass plate manufacturing apparatus, and a glass roll. Specifically, in the process of molten glass flowing down and forming a glass ribbon, both ends in the width direction of the glass ribbon are sandwiched from both front and back sides. The present invention relates to an improvement in manufacturing technology using a cooling roller.

  As is well known, in recent years, various glass plates including glass substrates for flat panel displays such as liquid crystal displays, plasma displays, and organic EL displays have been required to be further thinned. In response to the demand for such a thin plate, for example, as disclosed in Patent Document 1, a glass plate having a plate thickness thinner than 0.2 mm has already been developed.

  As a method for producing this type of thin glass plate, for example, an overflow down draw method such as a molten glass flowing down to form a glass ribbon and solidifying while further flowing down, or a down draw method such as a slot down draw method is used. The law is adopted.

  In this type of downdraw method, molten glass is allowed to flow down from a molded body to form a glass ribbon that is a base material of a glass plate. In this case, since the glass ribbon located immediately below the molded body has still a low viscosity, in the state as it is, the glass ribbon contracts in the width direction due to surface tension. For this reason, the glass ribbon is prevented from shrinking in the width direction by sandwiching both ends in the width direction of the low-viscosity glass ribbon with a pair of (two pairs in total) cooling rollers, for example, directly below the molded body. It is customary to maintain a predetermined width (see, for example, Patent Documents 1 and 2).

JP 2008-133174 A JP 2010-143800 A

  By the way, a glass ribbon may be conveyed in the state bent in the manufacturing process after cooling solidification, or may be accommodated in the state of the glass roll wound up by roll shape. In this case, the glass ribbon needs a certain degree of flexibility so that it can be bent.

  However, as described above, when the cooling roller is used in the process of forming the glass ribbon by the down draw method, both ends in the width direction of the glass ribbon as the contact portion of the cooling roller and the glass ribbon as the non-contact portion of the cooling roller. The difference of the shape accompanied by the plate thickness difference appears in the central part in the width direction. That is, as shown in FIG. 8, the glass ribbon G formed using the cooling roller has a product part Gb having a uniform thickness at the center in the width direction and is thicker than the product part Gb at both ends in the width direction. Ear part Ga is formed.

  Therefore, even if the glass ribbon product part is promoted to be thin, if the glass ribbon ears remain thick, the effect of the ears reduces the flexibility of the entire glass ribbon, resulting in sufficient bending deformation. Can not be tolerated. Therefore, when the glass ribbon having the ear portion is bent on the conveyance path or accommodated in the state of a glass roll, the minimum bending radius of the glass ribbon tends to be unreasonably large, which is a practical problem.

  In view of the above circumstances, an object of the present invention is to impart moderate flexibility to a glass ribbon having an ear and to make the minimum bending radius as small as possible.

The glass plate manufacturing method according to the present invention, which was devised to solve the above problems, is a process in which molten glass is flowed down to form a glass ribbon, and both end portions in the width direction of the glass ribbon are front and back with a pair of cooling rollers. In the glass plate manufacturing method in which the edge portions that are sandwiched from both sides and are thicker than the center portion in the width direction are formed at both ends in the width direction of the glass ribbon, the outer peripheral surfaces of at least one of the rollers as the pair of cooling rollers In the circumferential direction of the glass ribbon, a plurality of convex portions extending in the width direction of the glass ribbon are used, and by transferring the convex portions of the cooling roller, a thin portion having a minimum thickness of 300 μm or less is formed on the glass. the ears of the ribbon, intermittently forming a plurality along the longitudinal direction, the glass ribbon wherein the thin portion is formed on the ear portion, after cooling and solidifying, 50 cm or more Especially characterized bendable at a bend radius of deformation.

According to such a method, a plurality of thin portions extending along the width direction of the glass ribbon are intermittently formed in the longitudinal direction of the glass ribbon at the ear portions formed at both ends in the width direction of the glass ribbon. The And each thin part of an ear | edge part shall be 300 micrometers or less in minimum thickness. Here, if the minimum thickness of each thin portion of the ear portion is 300 μm or less, sufficient flexibility is imparted and it can withstand bending deformation with a small bending radius. Therefore, the flexibility of the ear part is partially improved at the position corresponding to the thin part, and the stress concentration generated in the ear part when the glass ribbon is bent is greatly reduced compared to the case without the thin part. Is done. Therefore, even if it has an ear | edge part, the whole glass ribbon can be easily curved in the longitudinal direction, and a bending radius can be made as small as possible. As a result, even when the glass ribbon is bent on the conveyance path or wound into a roll shape and accommodated in the state of the glass roll, the situation in which the bending radius of the glass roll is unduly expanded is surely prevented. be able to. In addition, since the bend radius of the glass ribbon having the ear portion is approximately the same as the bend radius of the glass ribbon from which the ear portion has been cut and removed, the glass roll can be wound while reducing restrictions on the transport path of the glass ribbon. The radius can be reduced.

  In the above method, it is preferable to use a pair of cooling rollers in which the convex portions are provided on the outer peripheral surfaces of both rollers.

  If it does in this way, the convex part of a cooling roller will be transcribe | transferred with respect to the front and back of the ear | edge part of a glass ribbon. Therefore, if the phase of each convex part in a pair of cooling roller is matched, the ear | edge part of a glass ribbon will be simultaneously pressed from both front and back surfaces by the convex part of a pair of cooling roller. Therefore, compared with the case where the convex part of the cooling roller is pressed only from one side of the ear part of the glass ribbon, the thin part can be easily formed on the ear part of the glass ribbon. Also, in this case, since grooves are formed on both the front and back surfaces corresponding to each of the thin portions at the ears of the glass ribbon, the glass ribbon is bent to the front side and the case to be bent to the back side. The bending deformation can be made substantially the same, and the handling becomes easy.

  Said method WHEREIN: The minimum thickness of the said thin part is below 1/2 of the maximum thickness of the thick part of the said ear | edge part formed between the said thin parts adjacent in the longitudinal direction of the said glass ribbon. Is preferred.

  In this way, since the difference in thickness between the thin wall portion and the thick wall portion can be sufficiently maintained at the ear portion of the glass ribbon, the effect of improving the flexibility of the glass ribbon in the thin wall portion can be reliably exhibited. It becomes possible.

  Said method WHEREIN: It is preferable to include the process of winding up the said glass ribbon in which the said thin part was formed in the said ear | edge part in roll shape.

  If it does in this way, the effect of this invention which formed the thin part in the ear | edge part can be exhibited to the maximum.

In addition, the glass plate manufacturing apparatus according to the present invention, which has been created to solve the above-described problems, is a process in which molten glass is flowed down to form a glass ribbon. In the glass plate manufacturing apparatus in which the edge portions that are sandwiched from both the front and back sides and are thicker than the widthwise central portion are formed at both widthwise end portions of the glass ribbon, at least one of the pair of cooling rollers has an outer periphery thereof A plurality of convex portions extending in the width direction of the glass ribbon in the circumferential direction of the surface, and by transferring the convex portions of the cooling roller, a thin portion having a minimum thickness of 300 μm or less is formed on the glass ribbon. the ear portion, the longitudinal direction intermittently forming a plurality along the glass ribbon wherein the thin portion is formed on the ear portion, after cooling and solidifying, the bending by the following bending radius 50cm Especially characterized possible form.

  Since the configuration of this apparatus is substantially the same as the configuration of the method described at the beginning of the glass plate manufacturing method according to the present invention described above, the explanation items including the effects are the explanation items already described for the method. Is substantially the same.

In addition, the glass roll according to the present invention, which was created in order to solve the above-mentioned problems, is a glass roll obtained by winding a glass ribbon having ears that are thicker than the central part in the width direction at both ends in the width direction. In the present invention, a plurality of thin portions extending in the width direction of the glass ribbon are intermittently formed along the longitudinal direction of the ear portions of the glass ribbon, and the minimum thickness of each thin portion is 300 μm or less. Ah is, the glass ribbon wherein the thin portion is formed on the ear portion, after cooling and solidifying, is marked particular feature is deformable bending below a bend radius 50 cm.

  According to such a glass roll, even a glass ribbon having an ear portion can be easily packed in the state of a glass roll, so that a long glass ribbon can be easily transported in the state of a glass roll. Is possible. Moreover, since the winding radius of a glass roll can be made small, space saving, such as a storage place, can be achieved.

  Said glass roll WHEREIN: It is preferable that the thickness of the width direction center part of the said glass ribbon is 300 micrometers or less.

  If it does in this way, in the width direction center part of a glass ribbon, since flexibility can fully be exhibited, it becomes possible to exhibit the flexibility improvement effect of the whole glass ribbon reliably.

  According to the present invention, since the thin-walled portion formed at the ear portion of the glass ribbon can impart appropriate flexibility to the glass ribbon having the ear portion, the bending radius can be made as small as possible. Can do.

It is a schematic front view which shows the principal part of the glass plate manufacturing apparatus which concerns on embodiment of this invention. It is the schematic which shows the principal part of the cooling roller used with the glass plate manufacturing apparatus which concerns on the said embodiment, (A) is a perspective view, (B) is radial direction sectional drawing. It is radial direction sectional drawing which shows the modification of the convex part of the cooling roller used with the glass plate manufacturing apparatus which concerns on the said embodiment. It is a cross-sectional top view which shows the state which clamped the glass ribbon with the cooling roller used with the glass plate manufacturing apparatus which concerns on the said embodiment. It is a schematic diagram which shows the glass ribbon manufactured with the glass plate manufacturing apparatus which concerns on embodiment of this invention, (A) is a top view, (B) is sectional drawing of the longitudinal direction of the width direction both ends. It is a schematic side view which shows the whole glass plate manufacturing apparatus which concerns on embodiment of this invention. It is a perspective view which shows the glass roll which concerns on embodiment of this invention. It is a cross-sectional view of a glass ribbon.

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

  FIG. 1: is a schematic front view which shows the principal part of the glass plate manufacturing apparatus which concerns on embodiment of this invention, Comprising: The process of manufacturing a glass plate by the overflow downdraw method is illustrated. As shown in the figure, the glass plate manufacturing apparatus 1 includes a molded body 3 having a cross-sectional shape (a cross-sectional shape orthogonal to the paper surface) having a substantially wedge shape inside a molding furnace 2 as follows. A glass ribbon G as a base material of a glass plate as a product is formed from molten glass. That is, first, molten glass g is continuously supplied to the overflow groove 4 formed on the upper portion of the molded body 3, and the molten glass g overflows from the overflow groove 4 to form side wall surfaces on both sides of the molded body 3 (both front and back sides of the paper). Along the side). And the molten glass g which flowed down is united in the lower top part of the molded object 3, respectively, and the glass ribbon G is shape | molded.

  In the process of flowing down the glass ribbon G, both ends in the width direction of the glass ribbon G are sandwiched from both the front and back sides by a pair (two pairs in total) of cooling rollers 5 just below the formed body 3. In this embodiment, the cooling roller 5 is disposed at a position where the glass ribbon G formed by flowing down from the molded body 3 reaches the annealer 6 disposed below the molded body 3. In this embodiment, both ends in the width direction of the glass ribbon G are sandwiched from both the front and back sides by a pair of annealer rollers 7 arranged in a plurality of stages inside the annealer 6.

  As shown in FIG. 2A, the cooling roller 5 is cantilevered by a roller shaft (rotation drive shaft) 5a extending from the width direction center portion side of the glass ribbon G toward both end portions. A plurality of convex portions 5 b extending along the central axis of the roller shaft 5 a are formed on the outer peripheral surface of the cooling roller 5 at equal intervals in the circumferential direction. These convex portions 5b have the same shape and the same dimensions. In this embodiment, as shown in FIG. 2B, each convex portion 5b has a prismatic shape with a substantially trapezoidal radial cross-sectional shape. Moreover, the outer surface of each convex part 5b is parallel to the center axis line of the roller shaft 5a. The outer peripheral surface of the cooling roller 5 between the convex portions 5b is also parallel to the central axis of the roller shaft 5a.

  In addition, the shape of the convex part 5b is not limited to the above-mentioned shape, The extension direction of a convex part shape should just be along the center axis line of the roller shaft 5a. As shown in FIG. 3A, the radial cross-sectional shape may be a semicircular column shape, or as shown in FIG. 3B, the radial cross-sectional shape may be a semi-elliptical column shape. . Further, as shown in FIG. 3C, the radial cross-sectional shape may be a prismatic shape such as a polygon such as a triangle, and further, as shown in FIG. 3D, the radial cross-sectional shape. May be a columnar shape having rounded corners of a polygon such as a triangle indicated by a dotted line. Moreover, in this embodiment, although the several convex part 5b is formed at equal intervals along the circumferential direction, you may be formed at unequal intervals along the circumferential direction.

  According to such a configuration, as shown in FIG. 4, the glass ribbon G sandwiched between the front and back sides of the pair of cooling rollers 5 at both ends in the width direction between the molded body 3 and the annealer 6, A product part Gb having a uniform thickness is formed at the center in the width direction, and an ear part Ga that is thicker than the product part Gb is formed at both ends in the width direction. At this time, in the ear portion Ga of the glass ribbon G, the plurality of convex portions 5 b of the cooling roller 5 are intermittently pressed from both the front and back sides with the rotation of the pair of cooling rollers 5. At this time, in this embodiment, the phases of the convex portions 5b of the pair of cooling rollers 5 are substantially coincident with each other, and the convex portions 5b of the pair of cooling rollers 5 have the ear portions Ga of the glass ribbon G in front and back. It is designed to be clamped at the same timing from both sides. As a result, as shown in FIG. 5A, the shape of the convex portion 5 b is transferred to both the front and back sides of the ear portion Ga of the glass ribbon G, and the transferred portion is the thin portion 8. When the plurality of convex portions 5b are formed at equal intervals along the circumferential direction on the outer peripheral surface of the cooling roller 5, a plurality of the thin portions 8 are formed at equal intervals in the longitudinal direction. Specifically, in the ear portion Ga of the glass ribbon G, the shape of the convex portion 5b is transferred from both the front and back sides at the same timing, so as shown in FIG. A plurality of grooves 9 are formed with the back surface recessed in a concave shape at the same position. A thin portion 8 is formed between the grooves 9 formed on both the front and back surfaces so as to face each other in the front and back direction. And each thin part 8 and the groove | channel 9 corresponding to each thin part 8 are formed so that it may extend along the width direction of the glass ribbon G corresponding to the extension direction of the convex part 5b of the cooling roller 5. FIG. The

  The minimum thickness b of each thin portion 8 is 300 μm or less. This is achieved by adjusting the height or the like of the convex portion 5b of the cooling roller 5.

  Thus, the glass ribbon G manufactured by the glass plate manufacturing apparatus 1 having the above-described configuration has the thin-walled portion 8 extending along the width direction of the glass ribbon G at the ear portion Ga, and the longitudinal direction of the glass ribbon G. Are formed intermittently. And each thin part 8 of the ear | edge part Ga shall be 300 micrometers or less in minimum thickness. Here, if the minimum thickness of each thin part 8 of the ear part Ga is 300 μm or less, the glass ribbon G is sufficiently flexible and can withstand bending deformation with a small minimum radius of curvature. Therefore, the flexibility of the ear part is partially improved at the position corresponding to the thin part 8, and the stress concentration generated in the ear part when the glass ribbon is bent is greatly compared with the case where there is no thin part. Alleviated. Therefore, even if it has the ear | edge part Ga, the whole glass ribbon G can be easily curved in the longitudinal direction, and the said bending radius can be made as small as possible. As a result, even when the glass ribbon G is bent on the transport path or wound into a roll shape and accommodated in the state of the glass roll, the situation where the bending radius of the glass roll is unduly expanded is surely prevented. can do.

  If the minimum thickness b of the thin portion 8 exceeds 300 μm, the bending radius may not be sufficiently small. On the other hand, the maximum thickness a between the thin portions 8 in the longitudinal direction of the ear portion Ga is, for example, 1 to 1.5 mm. If the thickness a is less than 1 mm, there is a possibility that a difference in bending radius from the case where the thin portion 8 does not exist is not sufficiently obtained, and if it exceeds 1.5 mm, the bending radius may not be sufficiently reduced. The value b / a of the ratio of the thickness b to the thickness a is 1/2 or less, more preferably 1/3 or less, and further preferably 1/5 or less. When b / a exceeds 1/2, there is a possibility that a difference in bending radius from the case where the thin portion 8 does not exist cannot be obtained sufficiently.

  Moreover, in the glass plate manufacturing apparatus 1 of this embodiment, the same convex part 5b is provided in the outer peripheral surface in all the two pairs of cooling rollers 5, and the convex part 5b of all the cooling rollers 5 is glass ribbon G simultaneously. As a result, the cooling roller 5 is driven in a synchronized state. For this reason, the position of the thin-walled portion 8 in the longitudinal direction of the glass ribbon G coincides between the two ear portions Ga.

  The thickness of the product part Gb of the glass ribbon G is 300 μm or less, more preferably 200 μm or less. When the thickness of the product part Gb exceeds 300 μm, the bending radius of the glass ribbon G may not be sufficiently reduced even if the thin part 8 is formed. In addition, the thickness of the product part Gb of the glass ribbon G is preferably the same as or smaller than the minimum thickness b of the thin part 8.

The viscosity of the position held by the cooling roller 5 in the ear portion Ga of the glass ribbon G is preferably 10 ^5.2 dPa · s or more, more preferably in the range of 10 ^5.7 to 10 ^7.5 dPa · s, and 10 ^6.0 to 10 ^7.0 dPa · s. The range of s is more preferable. If the viscosity at this position is less than 10 ^5.2 dPa · s, the glass ribbon G is so soft that the glass ribbon G is wound around the cooling roller 5 and the cooling roller 5 is liable to deteriorate. It can happen. If the viscosity at this position exceeds 10 ^7.5 dPa · s, the thin-walled portion 8 is not properly formed, and the bending radius of the glass ribbon G may not be reduced.

  The glass ribbon G is preferably bendable with a bending radius of 50 cm or less after cooling and solidification. When bending deformation is not possible with a bending radius of 50 cm or less, the bending radius of the glass ribbon G may not reach the bending radius of the glass ribbon G from which the ear portion Ga has been cut off. As a result, there is a possibility that it is difficult to reduce restrictions on the conveyance path of the glass ribbon G and to reduce the winding radius of the glass roll.

  Next, with reference to FIG. 6, the example of the whole structure of the glass plate manufacturing apparatus 1 and the glass plate manufacturing method by this glass plate manufacturing apparatus 1 are demonstrated.

  In the glass plate manufacturing apparatus 1 described above, a cooling furnace 11 is further disposed continuously below the annealer 6. Further, the glass plate manufacturing apparatus 1 includes winding means (not shown) for winding the glass ribbon G at a position shifted laterally from a position immediately below the cooling furnace 11. A winding core 13 around which the glass ribbon G is wound is attached to the winding means, and the winding means rotates the winding core 13 in the direction indicated by the arrow.

  In the glass plate manufacturing apparatus 1 having this configuration, as described above, the glass ribbon G is generated in the molding furnace 2 and the thin portion 8 is formed in the ear portion Ga by the cooling roller 5. It is gradually cooled. Further, inside the cooling furnace 11, while being cooled, the glass ribbon G is sandwiched by the plurality of rollers 12 from both the front and back sides and is driven and conveyed directly below. Then, the glass ribbon G is supported and driven by the support roller 14 so that the conveyance direction is changed to a substantially horizontal direction, and is conveyed to the core 13 that is rotationally driven by the side winding means. Therefore, the glass ribbon G is wound around the winding core 13 in a roll shape. At this time, the protective sheet 15 is rolled up on the outer peripheral side of the glass ribbon G.

  When the glass ribbon G is wound up to the roll core 13 until a predetermined roll diameter is reached, the glass ribbon G and the protective sheet 15 are cut. As a result, as shown in FIG. 7, the glass roll 16 formed by winding the glass ribbon G around the winding core 13 in a roll shape with the protective sheet 15 being stacked is completed.

  The inventors of the present invention compared the glass plate manufacturing apparatus provided with the above-described cooling roller with the glass plate manufacturing apparatus provided with the cooling roller having a smooth outer peripheral surface, and cooled and solidified glass after passing through the cooling roller. Performed based on ribbon. When this comparison is made, the flow rate of the molten glass flowing down from the molded body is constant under the condition that the total length in the width direction of the glass ribbon is 1500 mm and the thickness of the central portion (product portion) in the width direction of the glass ribbon is 0.2 mm. As a result, a glass ribbon was produced. Further, the cooling roller has a cylindrical shape with a diameter of 50 mm and is hollow inside, and has a structure in which a coolant such as water or air flows.

  Here, as an example of the present invention, as shown in FIG. 2, a cooling roller was used in which a plurality of convex portions extending along the central axis of the roller shaft were formed on the outer peripheral surface at equal intervals in the circumferential direction. As a comparative example, a cooling roller having a cylindrical surface with a smooth outer peripheral surface was used. Each of these cooling rollers has a central axis of the roller shaft extending in the horizontal direction as shown in FIG.

  About the glass ribbon manufactured using the cooling roller which concerns on said Example and comparative example, the convex part height of a cooling roller, the plate | board thickness ta of the width direction both ends (ear part), and the glass ribbon The minimum bending radius was measured. The results are shown in Table 1 below. In Table 1 below, the symbol Δ is slightly good, the symbol ◯ is good, the symbol ◎ is very good, and the symbol x means bad.

  According to Table 1 above, in Examples 1 to 3 of the present invention, compared to the comparative example, the height of the convex portion of the cooling roller is transferred to the shape of the end of the glass ribbon, and the minimum bending radius is good. It can be grasped that it has become. Further, from Examples 1 to 3, it can be seen that the minimum bending radius tends to decrease as the height of the convex portion increases.

  In addition, in the said embodiment, although the overflow downdraw method is used for manufacture of a glass plate, in this invention, the method used for glass plate manufacture is a method of producing | generating a glass ribbon by flowing down molten glass. For example, a slot down draw method or the like may be used.

  The present invention is not limited to the above description, and various modifications are possible within the scope of the technical idea.

DESCRIPTION OF SYMBOLS 1 Glass plate manufacturing apparatus 5 Cooling roller 5a Roller shaft 5b Convex part 8 Thin part 16 Glass roll G Glass ribbon g Molten glass Ga Ear part Gb Product part (width direction center part)

Claims (7)

In the process of forming the glass ribbon by letting the molten glass flow down, both ends in the width direction of the glass ribbon are sandwiched from both the front and back sides by a pair of cooling rollers, respectively, and at both ends in the width direction of the glass ribbon than the center in the width direction. In the glass plate manufacturing method in which the ears that are thick are formed,
As the pair of cooling rollers, a plurality of convex portions extending in the width direction of the glass ribbon are provided in the circumferential direction of the outer peripheral surface of at least one roller,
By transferring the convex portions of the cooling roller, a plurality of thin portions having a minimum thickness of 300 μm or less are intermittently formed along the longitudinal direction of the ear portions of the glass ribbon ,
The method for producing a glass plate , wherein the glass ribbon having the thin-walled portion formed in the ear portion can be bent and deformed with a bending radius of 50 cm or less after cooling and solidification . The glass plate manufacturing method according to claim 1, wherein the pair of cooling rollers is one in which the convex portions are provided on the outer peripheral surfaces of both rollers. The minimum thickness of the thin-walled portion is ½ or less of the maximum thickness of the thick-walled portion of the ear portion formed between the thin-walled portions adjacent in the longitudinal direction of the glass ribbon. Item 3. A method for producing a glass plate according to Item 1 or 2 . The method for producing a glass plate according to any one of claims 1 to 3 , further comprising a step of winding the glass ribbon having the thin-walled portion formed in the ear portion into a roll shape. In the process of forming the glass ribbon by letting the molten glass flow down, both ends in the width direction of the glass ribbon are sandwiched from both the front and back sides by a pair of cooling rollers, respectively, and at both ends in the width direction of the glass ribbon than the center in the width direction. In the glass plate manufacturing apparatus in which the ears that are thick are formed,
At least one of the pair of cooling rollers has a plurality of convex portions extending in the width direction of the glass ribbon in the circumferential direction of the outer peripheral surface thereof,
By transferring the convex portions of the cooling roller, a plurality of thin portions having a minimum thickness of 300 μm or less are intermittently formed along the longitudinal direction of the ear portions of the glass ribbon ,
The glass plate manufacturing apparatus , wherein the glass ribbon having the thin-walled portion formed in the ear portion can be bent and deformed with a bending radius of 50 cm or less after cooling and solidification . In the glass roll in which the glass ribbon having the ear part which is thicker than the widthwise center part at the widthwise both ends is wound up in a roll shape,
The thin portion extending in the width direction of the glass ribbon, in the ears of the glass ribbon, the longitudinal direction along the intermittently plurality formation, Ri minimum thickness is 300μm or less der of the thin portion of each ,
The glass roll in which the thin-walled portion is formed on the ear portion can be bent and deformed with a bending radius of 50 cm or less after cooling and solidification . The glass roll according to claim 6 , wherein a thickness of a central portion in the width direction of the glass ribbon is 300 μm or less.

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