BACKGROUND

1 . Cross- Reference to Related Applications

[0001] This application claims the benefit of priority under 35 U.S.C. § 119 of Korean Patent Application Serial No. 10-2021-0103907 filed on August 6, 2021 , the content of which is relied upon and incorporated herein by reference in its entirety.

2. Field

[0002] The disclosure relates to an apparatus, system, and method for forming a glass roll.

3. Description of the Related Art

[0003] Glass with thin thickness is bendable and flexible. The bendable and flexible glass may be used for flexible displays and wearable electronic apparatuses, or as decoration materials for building interior and exterior. Such flexible glass may be wound around a roll and stored and transported in the form of a glass roll. A necessary width of glass may vary depending on the end-consumer application. Accordingly, it is necessary to develop an apparatus, system, and method for forming a glass roll having a desired width without damaging the surface of glass.

SUMMARY

[0004] Provided is an apparatus, system, and method for forming a glass roll while preventing physical damage to glass.

[0005] Furthermore, provided is an apparatus, system, and method for quickly forming a glass roll.

[0006] Additional aspects will be set forth in part in the description which follows and, in part, will be apparent from the description, or may be learned by practice of the presented embodiments of the disclosure.

[0007] According to an aspect of the disclosure, an apparatus for forming a glass roll includes an unwinding apparatus configured to supply a glass ribbon by unwinding a first glass roll, a glass processing apparatus configured to process the glass ribbon, an air supply apparatus configured to supply air pressure to the glass ribbon such that the glass ribbon is separated from a surface of the glass processing unit, a winding apparatus configured to form a second glass roll by winding the processed glass ribbon, and a transfer roller in contact with at least a part of the glass ribbon, and configured to transfer the glass ribbon from the unwinding apparatus to the glass processing apparatus or from the glass processing apparatus to the winding apparatus, wherein a plurality of grooves are formed in a surface of the transfer roller.

[0008] In an embodiment, the transfer roller may have a cylindrical structure with a hollow center portion.

[0009] In an embodiment, the transfer roller may include a core layer having a cylindrical shape with a hollow center portion, and a coating layer covering a surface of the core layer.

[0010] In an embodiment, the core layer may include aluminum (Al), and the coating layer may include chromium (Cr).

[0011] In an embodiment, the plurality of grooves of the transfer roller may be provided in a ring shape surrounding a surface of the transfer roller, and the plurality of grooves may be arranged in a first direction parallel to a direction in which a rotation axis of the transfer roller extends.

[0012] In an embodiment, the length of the transfer roller in the first direction may be 1300 mm to 1500 mm.

[0013] In an embodiment, the pitch of the plurality of grooves may be 3 mm to 5 mm [0014] In an embodiment, the length of the transfer roller in a second direction perpendicular to the first direction may be 250 mm to 400 mm.

[0015] In an embodiment, the transfer roller may include an outer surface located at a distance from the rotation axis of the transfer roller, a plurality of inner-bottom surfaces located closer to the rotation axis of the transfer roller than the outer surface is, and a plurality of inner-side surfaces connecting the outer surface to the plurality of inner- bottom surfaces and defining the plurality of grooves with the plurality of inner-bottom surfaces, wherein an angle formed by the plurality of inner-side surfaces is 50° to 70°. [0016] In an embodiment, a first portion where the outer surface and each of the plurality of inner-side surfaces of the transfer roller contact each other may be rounded, and a second portion where each of the plurality of inner-bottom surfaces and each of the plurality of inner-side surfaces of the transfer roller contact each other may be rounded. [0017] In an embodiment, a first radius of curvature of the first portion where the outer surface and each of the inner-side surfaces of the transfer roller contact each other may be 0.2 mm to 0.4 mm, and a second radius of curvature of the second portion where each of the plurality of inner-bottom surfaces and each of the plurality of inner- side surfaces of the transfer roller contact each other may be 0.05 mm to 0.15 mm.

[0018] In an embodiment, a center-line average height roughness of the transfer roller may be 0.3 mm to 0.5 mm.

[0019] In an embodiment, each of the plurality of grooves of the transfer roller may have a line shape extending in a first direction parallel to a direction in which a rotation axis of the transfer roller extends.

[0020] In an embodiment, the glass processing apparatus may include at least one of a taping apparatus configured to attach a tape on at least a part of the glass ribbon, and a glass cutting apparatus configured to separate the glass ribbon into a first glass ribbon and a second glass ribbon.

[0021] According to another aspect of the disclosure, a system for forming a glass roll includes an unwinding unit configured to supply a glass ribbon by unwinding a first glass roll, a cutting unit configured to separate the glass ribbon into a first glass ribbon and a second glass ribbon, a winding unit configured to form a second glass roll by winding the first glass ribbon, and a transfer unit including a plurality of transfer rollers, each of the plurality of transfer rollers having a plurality of grooves in a surface thereof, arranged in at least one of a space between the unwinding unit and the cutting unit and a space between the cutting unit and the winding unit, and configured to transfer at least one of the glass ribbon and the first glass ribbon.

[0022] In an embodiment, the system may further include a taping unit configured to attach a tape on at least a part of the glass ribbon, a test unit configured to test the first glass ribbon, and a breaking unit configured to break the second glass ribbon.

[0023] In an embodiment, the cutting unit may include an air supply apparatus configured to supply air pressure to the glass ribbon such that the glass ribbon is separated from a surface of the glass processing unit, and the plurality of grooves included in each of the plurality of transfer rollers may provide an exhaust path of air supplied by the air supply apparatus.

[0024] In an embodiment, each of the plurality of transfer rollers may include a core layer having a hollow cylindrical structure, and a coating layer covering a surface of the core layer. [0025] In an embodiment, the core layer may include aluminum (Al), and the coating layer may include nickel (Ni).

[0026] In an embodiment, the length of each transfer roller in a first direction parallel to a direction in which a rotation axis of each transfer roller extends may be 1300 mm to 1500 mm, and the length of each transfer roller in a second direction perpendicular to the first direction may be 250 mm to 400 mm.

[0027] In an embodiment, the pitch of the plurality of grooves included in each of the transfer rollers may be 3 mm to 5 mm.

[0028] In an embodiment, each of the transfer rollers may include an outer surface located at a distance from the rotation axis of the transfer roller, a plurality of inner- bottom surfaces located closer to the rotation axis of the transfer roller than the outer surface is, and a plurality of inner-side surfaces connecting the outer surface with the each inner-bottom surface and defining the plurality of grooves with the plurality of the inner-bottom surfaces, wherein an angle formed by the plurality of inner-side surfaces may be 50° to 70°.

[0029] In an embodiment, a first portion where the outer surface and each of the inner- side surfaces of the transfer roller contact each other may be rounded, a second portion where each of the plurality of inner-bottom surfaces and each of the plurality of inner-side surfaces of the transfer roller contact each other may be rounded, a first radius of curvature of the first portion where the outer surface and each of the inner- side surfaces of the transfer roller contact each other may be 0.2 mm to 0.4 mm, and a second radius of curvature of the second portion where each of the plurality of inner- bottom surfaces and each of the plurality of inner-side surfaces of the transfer roller contact each other may be 0.05 mm to 0.15 mm.

[0030] According to another aspect of the disclosure, a method of forming a glass roll includes supplying a glass ribbon by unwinding a first glass roll, transferring the glass ribbon to a cutting unit through a first transfer roller that is in contact with the glass ribbon and has a plurality of grooves in a surface thereof, separating the glass ribbon into a first glass ribbon and a second glass ribbon when the glass ribbon is separated from a surface of the cutting unit, transferring the first glass ribbon to a winding unit through a second transfer roller that is in contact with the first glass ribbon and has a plurality of grooves in a surface thereof, and forming a second glass roll by winding the first glass ribbon through the winding unit. [0031] In an embodiment, the method may further include attaching of the tape on the at least a part of the glass ribbon testing the separated first glass ribbon, and breaking the separated second glass ribbon.

[0032] In an embodiment, the separating of the glass ribbon into the first glass ribbon and the second glass ribbon may include supplying air pressure to the glass ribbon such that the glass ribbon is separated from a surface of the cutting unit.

BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The above and other aspects, features, and advantages of certain embodiments of the disclosure will be more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0034] FIG. 1 is a schematic view of an apparatus for forming a glass roll, according to an embodiment of the disclosure;

[0035] FIG. 2 is a view of an operation of transferring a glass ribbon through a transfer roller, according to a comparative example;

[0036] FIG. 3 is a front view of a first transfer roller according to an embodiment of the disclosure;

[0037] FIG. 4 is an enlarged view of an area A of FIG. 3;

[0038] FIG. 5 is a side view of the first transfer roller of FIG. 3;

[0039] FIG. 6 is front view of a second transfer roller according to an embodiment of the disclosure;

[0040] FIG. 7 is a view of an operation of transferring a glass ribbon through a transfer roller, according to an embodiment of the disclosure;

[0041] FIG. 8 is a schematic view of a system for forming a glass roll, according to an embodiment of the disclosure;

[0042] FIG. 9 is a flowchart of a method of forming a glass roll, according to an embodiment of the disclosure; and

[0043] FIG. 10 is a flowchart of a method of forming a glass roll, according to another embodiment of the disclosure. DETAILED DESCRIPTION

[0044] Reference will now be made in detail to embodiments, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to like elements throughout. In this regard, the present embodiments may have different forms and should not be construed as being limited to the descriptions set forth herein. Accordingly, the embodiments are merely described below, by referring to the figures, to explain aspects of the present description. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. Expressions such as "at least one of," when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list.

[0045] Hereinafter, the disclosure will be described in detail by explaining preferred embodiments of the disclosure with reference to the attached drawings. This disclosure may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

[0046] Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to one of ordinary skill in the art. Like reference numerals in the drawings denote like elements. Furthermore, various elements and areas are schematically illustrated in the drawings. Accordingly, the concept of the disclosure is not limited by relatively sizes or intervals illustrated in the accompanying drawings.

[0047] While such terms as "first," "second," etc., may be used to describe various components, such components must not be limited to the above terms. The above terms are used only to distinguish one component from another. For example, without departing from the right scope of the disclosure, a first constituent element may be referred to as a second constituent element, and vice versa.

[0048] Terms used in the specification are used for explaining a specific embodiment, not for limiting the disclosure. Thus, an expression used in a singular form in the specification also includes the expression in its plural form unless clearly specified otherwise in context. Also, terms such as "include" or "comprise" may be construed to denote a certain characteristic, number, step, operation, constituent element, or a combination thereof, but may not be construed to exclude the existence of or a possibility of addition of one or more other characteristics, numbers, steps, operations, constituent elements, or combinations thereof. [0049] Unless defined otherwise, all terms used herein including technical or scientific terms have the same meanings as those generally understood by those of ordinary skill in the art to which the disclosure may pertain. The terms as those defined in generally used dictionaries are construed to have meanings matching that in the context of related technology and, unless clearly defined otherwise, are not construed to be ideally or excessively formal.

[0050] When a certain embodiment may be implemented differently, a specific process order may be performed differently from the described order. For example, two consecutively described processes may be performed substantially at the same time or performed in an order opposite to the described order.

[0051] In the accompanying drawings, variations from the shapes of the illustrations as a result, for example, of manufacturing techniques and/or tolerances, are to be expected. Thus, embodiments of the disclosure should not be construed as limited to the particular shapes of regions illustrated herein but are to include deviations in shapes that result, for example, from manufacturing. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.

[0052] FIG. 1 is a schematic view of an apparatus 10 for forming a glass roll, according to an embodiment of the disclosure.

[0053] The apparatus 10 for forming a glass roll according to an embodiment of the disclosure may provide a glass ribbon GR by unwinding a first glass roll R1 , process the glass ribbon GR that is provided, and form a second glass roll R2 by winding the glass ribbon GR that is processed. In other words, the apparatus 10 for forming a glass roll is used in a roll-to-roll process of forming the second glass roll R2 from the first glass roll R1.

[0054] The glass ribbon GR may have a certain width and extend in a direction, for example, a Y direction, perpendicular to the widthwise direction, for example, an X direction. The width of the glass ribbon GR may be about 100 mm to about 5000 mm. For example, the width of the glass ribbon GR may be about 1300 mm. Furthermore, the length of the glass ribbon GR extending in the Y direction may be about 10 meters to about 1000 meters. For example, the length of the glass ribbon GR extending in the Y direction may be about 300 meters.

[0055] Furthermore, the glass ribbon GR may have a thickness in a direction, for example, a Z direction, perpendicular to the direction in which the glass ribbon GR extends and the widthwise direction. The thickness of the glass ribbon GR may be about 50 pm to about 350 pm.

[0056] When the thickness of the glass ribbon GR is less than 50 pm, the glass ribbon GR is relatively thin and light, and thus the handling of the glass ribbon GR may be difficult. Furthermore, when the thickness of the glass ribbon GR exceeds about 350 pm, the glass ribbon GR is less flexible and thus the formation of a glass roll may be difficult.

[0057] In an embodiment, the glass ribbon GR may include silicate glass, borosilicate glass, aluminosilicate glass, boroaluminosilicate glass, or a combination thereof, and each may include or not include an alkali element(s). For example, the glass ribbon GR may be Willow® glass that is obtainable from Corning Incorporated.

[0058] Referring to FIG. 1 , the apparatus 10 for forming a glass roll according to an embodiment of the disclosure may include an unwinding apparatus 110, a glass processing apparatus 130, an air supply apparatus 150, a winding apparatus 170, a plurality of transfer rollers 200, and the like.

[0059] The unwinding apparatus 110 may be configured to supply the glass ribbon GR by unwinding the first glass roll R1. For example, the unwinding apparatus 110 may include a glass unwinder configured to unwind through rotation. Furthermore, the unwinding apparatus 110 may further include an interleaf remover, for example, an interleaf winder, configured to remove an interleaf of the first glass roll R1.

[0060] The glass processing apparatus 130 is configured to process the glass ribbon GR provided by the unwinding apparatus 110. Furthermore, the glass processing apparatus 130 may configured to process the glass ribbon GR while the glass ribbon GR is separated from a surface of the glass processing apparatus 130. In other words, the glass processing apparatus 130 may not be in contact with the glass ribbon GR.

[0061] In an embodiment, the glass processing apparatus 130 may be configured to separate the glass ribbon GR into a first glass ribbon and a second glass ribbon. In detail, the glass cutting apparatus may be configured to separate the glass ribbon GR into a first glass ribbon and a second glass ribbon while the glass ribbon GR is separated from a surface of the glass cutting apparatus.

[0062] For example, the glass ribbon GR may be separated from the surface of the glass cutting apparatus by about 10 pm to about 10 mm. However, a separation distance between the glass ribbon GR and the glass cutting apparatus is not limited to the above-described values. [0063] In an embodiment, the glass cutting apparatus may include a laser configured to heat the glass ribbon GR by irradiating laser light to the glass ribbon GR. For example, the laser may be a CO2 laser.

[0064] Furthermore, the glass cutting apparatus may further include optical elements for deforming the laser light. For example, the glass cutting apparatus may further include a polarizer, a beam expander, and a beam shaping apparatus. Furthermore, the glass cutting apparatus may further include a mirror and a lens.

[0065] Furthermore, the glass cutting apparatus may further include a cooling apparatus configured to cool a part of the glass ribbon GR that is heated by the irradiated laser light. For example, the cooling apparatus may be configured to supply a coolant to a surface of the glass ribbon GR. The coolant may include liquid, gas, or a combination thereof, for example, water.

[0066] In an embodiment, the glass processing apparatus 130 may include a taping apparatus configured to attach a tape on at least a part of the glass ribbon GR. In detail, the taping apparatus may be configured to attach a tape on an edge of the glass ribbon GR while the glass ribbon GR is separated from a surface of the taping apparatus.

[0067] In an embodiment, the taping apparatus may attach a tape on an edge portion of the glass ribbon GR for the handling of the glass ribbon GR. For example, the tape may include a polymer-based material.

[0068] As the glass processing apparatus 130 according to an embodiment of the disclosure processes the glass ribbon GR while the glass ribbon GR is separated from the surface of the glass processing apparatus 130, physical damage to the glass ribbon GR may be prevented.

[0069] The air supply apparatus 150 may be configured to provide air pressure to the glass ribbon GR so that the glass ribbon GR is separated from the surface of the glass processing apparatus 130.

[0070] In an embodiment, the air supply apparatus 150 may include a fan 153 configured to generate a flow of air, an exhaust flow path 155 providing an exhaust path of the air generated from the fan 153, and an intake flow path 157 providing an intake path of the air discharged through the exhaust flow path 155.

[0071] In an embodiment, the fan 153 may generate a flow of air in the glass ribbon GR in a direction perpendicular to a direction in which the glass ribbon GR extends. For example, the fan 153 may generate a flow of air in a direction from a lower surface of the glass ribbon GR toward an upper surface thereof.

[0072] Furthermore, the exhaust flow path 155 may provide an exhaust path of the air generated from the fan 153, and the intake flow path 157 may provide an intake path of the air exhausted from the exhaust flow path 155. In other words, the air generated from the fan 153 may be moved from the exhaust flow path 155 to the intake flow path 157, and the air may provide air pressure to the surface of the glass ribbon GR.

[0073] The winding apparatus 170 may be configured to form the second glass roll R2 by winding the glass ribbon GR that is processed through the glass processing apparatus 130. For example, the winding apparatus 170 may include a glass winder that forms the second glass roll R2 by winding the glass ribbon GR processed through rotation. Furthermore, the winding apparatus 170 may further include an interleaf unwinder that is configured to supply an interleaf to the glass ribbon GR that is processed. For example, the winding apparatus 170 may form the second glass roll R2 by winding the glass ribbon GR that is processed, with the interleaf.

[0074] In an embodiment, when the glass processing apparatus 130 separates the glass ribbon GR into a first glass ribbon and a second glass ribbon, the winding apparatus 170 may form the second glass roll R2 by winding the first glass ribbon.

[0075] The transfer rollers 200 may be configured to transfer the glass ribbon GR from the unwinding apparatus 110 to the glass processing apparatus 130, or the glass ribbon GR from the glass processing apparatus 130 to the winding apparatus 170.

[0076] Furthermore, the transfer rollers 200 may be idle rollers arranged between the unwinding apparatus 110 and the winding apparatus 170 that are operated by power, and configured to be rotated by a tension of the glass ribbon GR that is to be transferred.

[0077] Furthermore, the transfer rollers 200 may include a plurality of transfer rollers. At least one of the transfer rollers 200 may have a plurality of grooves G in a surface thereof.

[0078] An apparatus for forming a glass roll according to a comparative example may include the unwinding apparatus 110, the glass processing apparatus 130, the air supply apparatus 150, and the winding apparatus 170, which are described above. In other words, the apparatus for forming a glass roll according to a comparative example may not include a transfer roller contacting the glass ribbon GR. [0079] In this case, in a processing process of the glass ribbon GR, for example, a separation process of the glass ribbon GR, using the glass processing apparatus 130, slipping of the glass ribbon GR may be generated. Accordingly, the speed and yield of the processing process of the glass ribbon GR may be reduced.

[0080] Furthermore, in the apparatus for forming a glass roll according to a comparative example, it may be difficult to uniformly maintain the air height of the glass ribbon GR through the air supply apparatus 150. Accordingly, due to irregular tension provided to the glass ribbon GR, the glass ribbon GR may be physically damaged.

[0081] Accordingly, the apparatus 10 for forming a glass roll according to an embodiment of the disclosure may include the transfer rollers 200 that prevents physical damage to the glass ribbon GR and also improve the speed and yield of the processing process of the glass ribbon GR.

[0082] In the following description, the technical concept of the transfer rollers 200 according to an embodiment of the disclosure is described in detail.

[0083] FIG. 2 is a view of an operation of transferring a glass ribbon GR' through a transfer roller 200', according to a comparative example.

[0084] Referring to FIG. 2, the transfer roller 200' may be a general idle roller having a cylindrical shape. When the glass ribbon GR' is transferred through the transfer roller 200', air provided by the air supply apparatus 150 of FIG. 1 may be caught between the transfer roller 200' and the glass ribbon GR'. In other words, an air pocket AP' may be formed between the transfer roller 200' and the glass ribbon GR'.

[0085] As air is caught between the transfer roller 200' and the glass ribbon GR', when the speed of the transfer roller 200' is gradually increased, friction between the glass ribbon GR' and the transfer roller 200' may be lost. For example, when the speed of the transfer roller 200' is gradually increased, the speed of the surface of the transfer roller 200' and the transfer speed of the glass ribbon GR' may be different from each other. Accordingly, the yield of the processing process of the glass ribbon GR' may be reduced, and the glass ribbon GR' may be physically damaged.

[0086] In the following description, to address the above-described issues, first and second transfer rollers 230 and 260 according to embodiments of the disclosure are described in detail.

[0087] FIG. 3 is a front view of the first transfer roller 230 according to an embodiment of the disclosure. Furthermore, FIG. 4 is an enlarged view of an area A of FIG. 3. Furthermore, FIG. 5 is a side view of the first transfer roller 230 of FIG. 3. [0088] Referring to FIGS. 3 to 5 together, the first transfer roller 230 according to an embodiment of the disclosure may have a cylinder structure having a hollow center portion. Furthermore, the first transfer roller 230 may have the grooves G in the surface thereof.

[0089] The first transfer roller 230 may be configured to rotate around a rotation axis C extending in a first direction X. In an embodiment, the length of the first transfer roller 230 in the first direction X may be about 1300 mm to about 1500 mm. For example, the length of the first transfer roller 230 in the first direction X may be about 1400 mm. [0090] Furthermore, the length of the first transfer roller 230 in the second direction Y perpendicular to the first direction X, that is, the diameter of the first transfer roller 230, may be about 250 mm to about 400 mm. For example, the length of the first transfer roller 230 in the second direction Y may be about 300 mm, that is, about 12 inches.

[0091] When the length of the first transfer roller 230 in the second direction Y is less than 250 mm, the curvature of the glass ribbon GR that passes the first transfer roller 230 increases so that the amount of stress applied to the glass ribbon GR may be increased. Accordingly, the glass ribbon GR may be physically damaged.

[0092] Furthermore, when the length of the first transfer roller 230 in the second direction Y exceeds 400 mm, due to an increase in the size and weight of the first transfer roller 230, the rotation of the first transfer roller 230 may be relatively difficult. Accordingly, the transfer speed of the glass ribbon GR by the first transfer roller 230 may be reduced, the size of an apparatus for forming a glass roll including the first transfer roller 230 may be increased.

[0093] As the length of the first transfer roller 230 in the second direction Y is about 250 mm to about 400 mm, physical damage to the glass ribbon GR may be prevented, and the transfer speed of the glass ribbon GR may be improved.

[0094] Furthermore, the first transfer roller 230 may include an outer surface 230_SO forming a first distance from the rotation axis C, an inner-bottom surface 230_SB forming a second distance from the rotation axis C that is less than the first distance, and an inner-side surface 230_SS connecting the outer surface 230_SO to the inner- bottom surface 230_SB.

[0095] Furthermore, the inner-bottom surface 230_SB and the inner-side surface 230_SS of the first transfer roller 230 together may define each of the grooves G. Each of the grooves G of the first transfer roller 230 may have a taper shape in which a width thereof gradually decreases closer to the rotation axis C. [0096] In an embodiment, referring to FIG. 5, the first transfer roller 230 may include a core layer 233 provided in a cylindrical shape with a hollow center portion, and a coating layer 235 surrounding a surface of the core layer 233.

[0097] In an embodiment, the core layer 233 may include aluminum (Al), and the coating layer 235 may include chromium (Cr). As the core layer 233 of the first transfer roller 230 includes Al, and the coating layer 235 include Cr, the physical damage to the glass ribbon GR by the first transfer roller 230 may be prevented. Furthermore, as the first transfer roller 230 may be light, the transfer speed of the glass ribbon GR by the first transfer roller 230 may be improved.

[0098] Furthermore, as the coating layer 235 of the first transfer roller 230 may include Cr, a frictional coefficient between the first transfer roller 230 and the glass ribbon GR may be improved. Accordingly, the glass ribbon GR may not slip on the surface of the first transfer roller 230.

[0099] The first transfer roller 230 may the grooves G. In an embodiment, the grooves G may have a ring shape surrounding the surface of the first transfer roller 230. Furthermore, the grooves G may be arranged in the first direction X that is parallel to the direction in which the rotation axis C of the first transfer roller 230 extends.

[00100] In an embodiment, an angle a formed between two neighboring inner-side surfaces 230_SS defining one of the grooves G of the first transfer roller 230 may be about 50° to about 70°. For example, the angle a of the two inner-side surfaces 230_SS defining one of the grooves G may be about 60°.

[00101] Furthermore, a depth G_d of each of the grooves G of the first transfer roller 230 may be about 0.3 mm to about 0.7 mm. For example, the depth G_d of each of the grooves G of the first transfer roller 230 may be about 0.5 mm.

[00102] Furthermore, a pitch p of the grooves G may be about 3 mm to about 5 mm. The pitch p may be defined as an interval between valleys formed by the two neighboring grooves G. For example, the pitch p of the grooves G may be about 4 mm. [00103] Furthermore, center-line average height roughness Ra of the surface of the first transfer roller 230 may be about 0.3 mm to about 0.5 mm. For example, the center- line average height roughness Ra of the surface of the first transfer roller 230 may be about 0.4 mm.

[00104] The center-line average height roughness Ra of the first transfer roller 230 may be defined to be a value obtained by dividing an area formed as a curved line is separated from a center line in a section, by a length L, when the curved line formed by the surface of the first transfer roller 230 is set to be a virtual center line in a section having a certain length, for example, L.

[00105] When the center-line average height roughness Ra of the first transfer roller 230 is less than 0.3 mm, friction between the glass ribbon GR and the first transfer roller 230 may be reduced. Accordingly, the glass ribbon GR may be prevented from slipping on the surface of the first transfer roller 230.

[00106] Furthermore, when the center-line average height roughness Ra of the first transfer roller 230 exceeds 0.5 mm, the glass ribbon GR may be damaged by the surface of the first transfer roller 230.

[00107] In other words, as the surface of the center-line average height roughness Ra of the first transfer roller 230 is about 0.3 mm to about 0.5 mm, the glass ribbon GR may not slip on the surface of the first transfer roller 230, and the glass ribbon GR may not be damaged by the first transfer roller 230.

[00108] In an embodiment, a contact portion between the outer surface 230_SO and the inner-side surface 230_SS of the first transfer roller 230 may be defined as a first part P1. Furthermore, the first part P1 of first transfer roller 230 may be rounded.

[00109] Furthermore, a contact portion between the inner-side surface 230_SS and the inner-bottom surface 230_SB of the first transfer roller 230 may be defined as a second part P2. Furthermore, the second part P2 of the first transfer roller 230 may be rounded. [00110] As the first part P1 and the second part P2 of the first transfer roller 230 is rounded, the physical damage to the glass ribbon GR by the surface of the first transfer roller 230 may be prevented.

[00111] For example, the curvature of the first part P1 where the outer surface 230_SO and the inner-side surface 230_SS of the first transfer roller 230 contact each other may be less than the curvature of the second part P2 where the inner-side surface 230_SS and the inner-bottom surface 230_SB of the first transfer roller 230 contact each other. In other words, the radius of curvature of the first part P1 may be greater than the radius of curvature of the second part P2.

[00112] In an embodiment, the radius of curvature of the first part P1 of the first transfer roller 230 may be about 0.2 mm to about 0.4 mm, and the radius of curvature of the second part P2 of the first transfer roller 230 may be about 0.05 mm to 0.15 mm.

[00113] FIG. 6 is front view of the second transfer roller 260 according to an embodiment of the disclosure. [00114] In the following description, redundant descriptions between the first transfer roller 230 described with reference to FIGS. 3 to 5 and the second transfer roller 260 of FIG. 6 are omitted, and differences therebetween are mainly described.

[00115] The second transfer roller 260 according to an embodiment of the disclosure may include a plurality of grooves Ga extending in the first direction X parallel to the direction in which the rotation axis C of the second transfer roller 260 extends.

[00116] The second transfer roller 260 may include a core layer in a cylindrical shape with a hollow center portion, and a coating layer surrounding a surface of the core layer. Furthermore, the core layer may include Al, and the coating layer may include Cr.

[00117] Furthermore, the grooves Ga of the second transfer roller 260 may each have a taper shape in which a width thereof gradually decreases closer to the rotation axis C. For example, an angle a formed by two neighboring inner-side surfaces defining one of the grooves Ga of the second transfer roller 260 may be about 50° to about 70°. [00118] Furthermore, the depth of one of the grooves Ga of the second transfer roller 260 may be about 0.3 mm to about 0.7 mm. Furthermore, the pitch of the grooves Ga may be about 3 mm to about 5 mm. Furthermore, the center-line average height roughness of the surface of the second transfer roller 260 may be about 0.3 mm to about 0.5 mm.

[00119] In an embodiment, a first part that is a portion where the outer surface and inner-side surface of the second transfer roller 260 contact each other may be rounded. For example, the radius of curvature of the first part may be about 0.2 mm to about 0.4 mm. Furthermore, a second part that is a portion where the inner-side surface and the inner-bottom surface of the second transfer roller 260 contact each other may be rounded. For example, the radius of curvature of the second part may be about 0.05 mm to 0.15 mm.

[00120] FIG. 7 is a view of an operation of transferring the glass ribbon GR through the transfer roller 200, according to an embodiment of the disclosure.

[00121] The transfer rollers 200 according to an embodiment of the disclosure may include the first transfer roller 230 and the second transfer roller 260 that are described with reference o FIGS. 3 to 6.

[00122] As the transfer rollers 200 according to an embodiment of the disclosure is provided in a cylinder shape with a hollow center portion, the weight of the transfer rollers 200 may be reduced. Accordingly, the transfer speed of the glass ribbon GR by the rotation of the transfer rollers 200 may be improved.

[00123] Furthermore, as the transfer rollers 200 according to an embodiment of the disclosure include the coating layer 235 of FIG. 5 including Cr, the frictional coefficient between the transfer rollers 200 and the glass ribbon GR may be improved. Accordingly, the glass ribbon GR may not slip on the surfaces of the transfer rollers 200.

[00124] Furthermore, as the transfer rollers 200 according to an embodiment of the disclosure include each of the grooves G in each surface thereof, a frictional coefficient between the transfer rollers 200 and the glass ribbon GR may be improved. Accordingly, the glass ribbon GR may not slip on the surfaces of the transfer rollers 200.

[00125] Furthermore, as the transfer rollers 200 according to an embodiment of the disclosure may include the grooves G in the surfaces thereof, the air generated from the air supply apparatus 150 of FIG. 1 may be moved through the grooves G of the transfer rollers 200, so as not to be caught in the space between each of the transfer rollers 200 and the glass ribbon GR. In other words, the air pocket AP' of FIG. 2 may not be formed in the space between each of the transfer rollers 200 and the glass ribbon GR.

[00126] Accordingly, although the speed of the transfer rollers 200 is gradually increased, the glass ribbon GR may not slip on the surfaces of the transfer rollers 200. [00127] Furthermore, the length in the second direction Y, that is, the diameter, of each of the transfer rollers 200 according to an embodiment of the disclosure may be about 250 mm to about 400 mm. Accordingly, physical damage to the glass ribbon GR by the transfer rollers 200 may be reduced, and the transfer speed of the glass ribbon GR may be improved.

[00128] FIG. 8 is a schematic view of a system 1 for forming a glass roll, according to an embodiment of the disclosure.

[00129] The system 1 for forming a glass roll according to an embodiment of the disclosure may include an unwinding unit 300, a taping unit 400, a cutting unit 500, a breaking unit 600, a test unit 700, a winding unit 800, and a transfer unit 900.

[00130] The system 1 for forming a glass roll according to an embodiment of the disclosure may be configured to supply the glass ribbon GR by unwinding the first glass roll R1 , separate the glass ribbon GR that is supplied, into a first glass ribbon GR1 and a second glass ribbon GR2, test the first glass ribbon GR1 , break the second glass ribbon GR2, and form the second glass roll R2 by winding the first glass ribbon GR1. In other words, the system 1 for forming a glass roll may be used in a roll-to-roll process of forming the second glass roll R2 from the first glass roll R1.

[00131] The unwinding unit 300 may include an apparatus configured to supply the glass ribbon GR by unwinding the first glass roll R1. For example, the unwinding unit 300 may be substantially the same as the unwinding apparatus 110 of FIG. 1. For example, the unwinding unit 300 may include a glass unwinder configured to unwind the first glass roll R1.

[00132] The taping unit 400 may include an apparatus configured to attach a tape on at least a part of the glass ribbon GR. For example, the taping unit 400 may be configured to attach a tape on an edge portion of the glass ribbon GR. Furthermore, the taping unit 400 may be configured to attach a tape on an edge portion of the glass ribbon GR while the glass ribbon GR is separated from the surface of the taping unit 400.

[00133] In an embodiment, the taping unit 400 may be configured to attach a tape at an edge of the glass ribbon GR for the handling of the glass ribbon GR. For example, the tape may include a polymer-based material.

[00134] Furthermore, the air supply apparatus 150 described with reference to FIG. 1 may be arranged below the taping unit 400. The air supply apparatus 150 may provide air pressure to the glass ribbon GR so that the glass ribbon GR is separated from the surface of the taping unit 400.

[00135] The cutting unit 500 may be configured to separate the glass ribbon GR into the first glass ribbon GR1 and the second glass ribbon GR2. The cutting unit 500 may include the glass cutting apparatus of the glass processing apparatus 130 of FIG. 1.

[00136] In an embodiment, the cutting unit 500 may separate the glass ribbon GR into the first glass ribbon GR1 and the second glass ribbon GR2 while the glass ribbon GR is separated from the surface of the cutting unit 500. For example, the glass ribbon GR may be separated from the surface of the cutting unit 500 by about 10 pm to about 10 mm. However, a separation distance between the glass ribbon GR and the cutting unit 500 is not limited to the above-described values.

[00137] In an embodiment, the cutting unit 500 may separate the glass ribbon GR into the first glass ribbon GR1 and the second glass ribbon GR2 so that the first glass ribbon GR1 has a necessary width by a customer. For example, the width of the first glass ribbon GR1 may be greater than the width of the second glass ribbon GR2.

[00138] In an embodiment, the cutting unit 500 may include a laser configured to heat the glass ribbon GR by irradiating laser light to the glass ribbon GR. For example, the laser may be a CO2 laser.

[00139] The breaking unit 600 may include a glass breaking apparatus configured to break the second glass ribbon GR2 that is separated. For example, the breaking unit 600 may break the second glass ribbon GR2 by hitting at least a part of the second glass ribbon GR2. For example, the breaking unit 600 may include at least one of a hammer configured to apply an impact to the second glass ribbon GR2, and a breaking roller including a breaking pin.

[00140] The test unit 700 may be configured to test the first glass ribbon GR1. For example, the test unit 700 may be configured to expose the first glass ribbon GR1 to various conditions to test performance of the first glass ribbon GR1 in the conditions.

[00141] For example, the test unit 700 may include at least one of a heat source configured to apply heat to the first glass ribbon GR1 , a roller configured to apply a tension to the first glass ribbon GR1 , a fan configured to blow air to the first glass ribbon GR1 , and a camera configured to observe the surface of the first glass ribbon GR1.

[00142] The winding unit 800 may be configured to form the second glass roll R2 by winding the first glass ribbon GR1 through rotation. In an embodiment, the winding unit 800 may include the winding apparatus 170 of FIG. 1. For example, the winding unit 800 may include a glass winder configured to form the second glass roll R2 by winding the first glass ribbon GR1 through rotation.

[00143] The transfer unit 900 may be arranged in a space between the unwinding unit 300 and the taping unit 400, a space between the taping unit 400 and the cutting unit 500, a space between the cutting unit 500 and the test unit 700, and a space between the test unit 700 and the winding unit 800.

[00144] Furthermore, the transfer unit 900 may include a plurality of first to fourth transfer rollers 200a to 200d, each having the grooves G of FIG. 7 in the surface thereof. In an embodiment, the first to fourth transfer rollers 200a to 200d may be arranged any one of the space between the unwinding unit 300 and the taping unit 400, the space between the taping unit 400 and the cutting unit 500, the space between the cutting unit 500 and the test unit 700, and the space between the test unit 700 and the winding unit 800, and configured to transfer the glass ribbon GR through rotation.

[00145] As the technical concepts of the first to fourth transfer rollers 200a to 200d are substantially the same as those of the transfer rollers 200 described with reference to FIGS. 1 to 7, detailed descriptions thereof are omitted.

[00146] In an embodiment, as illustrated in FIG. 8, the first transfer roller 200a may be arranged between the unwinding unit 300 and the taping unit 400. The second transfer roller 200b may be arranged in the space between the cutting unit 500 and the test unit 700. Furthermore, the third and fourth transfer rollers 200c and 200d may be arranged between the test unit 700 and the winding unit 800. However, the arrangement of the first to fourth transfer rollers 200a to 200d is not limited to the illustration of FIG. 8.

[00147] In an embodiment, the grooves formed in the surface of the first transfer roller 200a may provide an exhaust path of the air provided by the air supply apparatus 150. As the air generated from the air supply apparatus 150 is moved through the grooves of the first transfer roller 200a, the air may not be caught in the space between the first transfer roller 200a and the glass ribbon GR. In other words, no air pocket may be formed in the space between the first transfer roller 200a and the glass ribbon GR. Accordingly, as the speed of the first transfer roller 200a is gradually increased, the glass ribbon GR may not slip on the surface of the first transfer roller 200a.

[00148] In an embodiment, the first to fourth transfer rollers 200a to 200d may each include the core layer 233 of FIG. 5 having a cylindrical structure with a hollow center portion and the coating layer 235 of FIG. 5 surrounding the surface of the core layer 233.

[00149] For example, the core layer 233 may include Al, and the coating layer 235 may include Cr. As the technical concepts of the core layer 233 and the coating layer 235 are substantially the same as those described with reference to FIG. 5, detailed descriptions thereof are omitted.

[00150] In an embodiment, the lengths of the first to fourth transfer rollers 200a to 200d in the first direction X that is parallel to a direction in which the rotation axes of the first to fourth transfer rollers 200a to 200d extend may be about 1300 mm to about 1500 mm. Furthermore, the length of the first to fourth transfer rollers 200a to 200d in the second direction Y perpendicular to the first direction X may be about 250 mm to about 400 mm. [00151] Furthermore, the pitch p (see FIG. 4) of the grooves of the first to fourth transfer rollers 200a to 200d may be about 3 mm to about 5 mm.

[00152] In an embodiment, as described with reference to FIGS. 3 and 4, the first to fourth transfer rollers 200a to 200d may each include the outer surface 230_SO of FIG.

4 forming the first distance from the rotation axis C of FIG. 3, the inner-bottom surface 230_SB of FIG. 4 forming the second distance from the rotation axis C that is less than the first distance, and the inner-side surface 230_SS of FIG. 4 connecting the outer surface 230_SO to the inner-bottom surface 230_SB. Furthermore, the inner-bottom surface 230_SB and the inner-side surface 230_SS together may define the groove. The groove G may have a taper shape in which a width thereof gradually decreases closer to the rotation axis C.

[00153] In an embodiment, the angle a formed by two neighboring inner-side surfaces 230_SS defining one of the grooves of first to fourth transfer rollers 200a to 200d may be about 50° to about 70°. For example, the angle a formed by the two inner-side surfaces 230_SS forming one groove may be about 60°.

[00154] Furthermore, the depth G_d (see FIG. 4) of the first to fourth transfer rollers 200a to 200d may be about 0.3 mm to about 0.7 mm.

[00155] Furthermore, the pitch p of the grooves of the first to fourth transfer rollers 200a to 200d may be about 3 mm to about 5 mm. The pitch p may be defined as an interval between valleys formed by the two neighboring grooves.

[00156] Furthermore, the center-line average height roughness of the surfaces of the first to fourth transfer rollers 200a to 200d may be about 0.3 mm to about 0.5 mm.

[00157] In an embodiment, the first part P1 where the outer surface 230_SO of FIG. 4 and the inner-side surface 230_SS of FIG. 4 of the first to fourth transfer rollers 200a to 200d contact each other may be rounded. Furthermore, the second part P2 of FIG.

4 where the inner-side surface 230_SS of FIG. 4 and the inner-bottom surface 230_SB of FIG. 4 of the first to fourth transfer rollers 200a to 200d contact each other may be rounded.

[00158] In an embodiment, the radius of curvature of the first part P1 of the first to fourth transfer rollers 200a to 200d may be about 0.2 mm to about 0.4 mm, and the radius of curvature of the second part P2 of the first to fourth transfer rollers 200a to 200d may be about 0.05 mm to 0.15 mm.

[00159] FIG. 9 is a flowchart of a method S100 of forming a glass roll, according to an embodiment of the disclosure. The method S100 of forming a glass roll according to an embodiment of the disclosure may be a method of forming a glass roll using the system 1 for forming a glass roll that is described with reference to FIG. 8.

[00160] Referring to FIG. 9, the method S100 of forming a glass roll may include supplying the glass ribbon GR of FIG. 8 by unwinding the first glass roll R1 of FIG. 8 (S1100), transferring the glass ribbon GR to the cutting unit 500 of FIG. 8 through the first transfer roller 200a of FIG. 8 that is in contact with the glass ribbon GR and has grooves in the surface thereof (S1200), separating the glass ribbon GR into the first glass ribbon GR1 and the second glass ribbon GR2 while the glass ribbon GR is separated from the surface of the cutting unit 500 (S1300), transferring the glass ribbon GR to the winding unit 800 of FIG. 8 through the second transfer rollers 200c and 200d of FIG. 8 that are in contact with the first glass ribbon GR1 and have the grooves in the surfaces thereof (S1400), and forming the second glass roll R2 by winding the first glass ribbon GR1 through the winding unit 800 of FIG. 8 (S1500).

[00161] In an embodiment, operation S1300 may include lifting the glass ribbon GR from the surface of the cutting unit 500 by providing air pressure to the glass ribbon GR, and separating the glass ribbon GR into the first glass ribbon GR1 and the second glass ribbon GR2 using a laser.

[00162] The air provided to lift the glass ribbon GR may be discharged to the outside through the grooves of the first transfer roller 200a. Accordingly, the air may not be caught in the space between the glass ribbon GR and the first transfer roller 200a.

[00163] The transfer rollers used in operation S1200 and operation S1400 may be substantially the same as those described with reference to FIGS. 1 to 8. Accordingly, the method S100 of forming a glass roll according to an embodiment of the disclosure may prevent physical damage to the glass ribbon GR and quickly process the glass ribbon GR. Accordingly, yield of the process of forming a glass roll may be improved. [00164] FIG. 10 is a flowchart of a method S200 of forming a glass roll, according to another embodiment of the disclosure.

[00165] Referring to FIG. 10, the method S200 of forming a glass roll according to another embodiment of the disclosure may include supplying the glass ribbon GR of FIG. 8 by unwinding the first glass roll R1 of FIG. 8 (S1100), attaching a tape on at least a part of the glass ribbon GR (S1150), transferring the glass ribbon GR to the cutting unit 500 of FIG. 8 through the first transfer roller 200a of FIG. 8 that is in contact with the glass ribbon GR and has grooves in the surface thereof (S1200), separating the glass ribbon GR into the first glass ribbon GR1 and the second glass ribbon GR2 while the glass ribbon GR is separated from the surface of the cutting unit 500 (S1300), testing the first glass ribbon GR1 (S1350), breaking the second glass ribbon GR2 (S1370), transferring the glass ribbon GR to the winding unit 800 of FIG. 8 through the second transfer rollers 200c and 200d of FIG. 8 that are in contact with the first glass ribbon GR1 and have the grooves in the surfaces thereof (S1400), and forming the second glass roll R2 by winding the first glass ribbon GR1 through the winding unit 800 of FIG. 8 (S1500).

[00166] According to the method S200 of forming a glass roll according to an embodiment of the disclosure, as the glass ribbon GR may be transferred through the transfer rollers 200a to 200d of FIG. 8 having the grooves in the surfaces thereof, physical damage to the glass ribbon GR may be prevented, and the transfer speed of the glass ribbon GR may be improved.

[00167] It should be understood that embodiments described herein should be considered in a descriptive sense only and not for purposes of limitation. Descriptions of features or aspects within each embodiment should typically be considered as available for other similar features or aspects in other embodiments. While one or more embodiments have been described with reference to the figures, it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the disclosure as defined by the following claims.