JP2023087933A - Method for manufacturing glass plate - Google Patents

Abstract

To allow bonding avoiding occurrence of wrinkles when including the step of bonding a thin glass plate having flexibility to a support glass to prepare a laminate when manufacturing the glass plate.SOLUTION: A method for manufacturing a glass plate includes a lamination step P2 of preparing a laminate 3 having both glasses 1 and 2 superimposed by contacting surfaces of a glass plate 1 arranged on a surface plate 4 and having flexibility to a support glass 2 for supporting the glass plate 1 and radially expanding an area bonding both glasses 1 and 2 from the start point of the bonding. In the lamination step P2, both glasses 1 and 2 are bonded in a state of sucking the glass plate 1 by a negative pressure from the surface plate 4.SELECTED DRAWING: Figure 3

Description

TECHNICAL FIELD The present disclosure relates to a method for manufacturing a glass plate, including a step of bonding a flexible thin glass plate and a support glass that supports the glass plate to produce a laminate.

At present, glass substrates incorporated in displays represented by liquid crystal displays, plasma displays, etc. are being made thinner, and along with this, thin glass plates (for example, thickness of 100 μm or less) are being manufactured. . Such a thin glass plate has a property of being rich in flexibility.

When applying a treatment (for example, film formation) to a thin glass plate, for the purpose of facilitating the handling of the glass plate, the surfaces of the glass plate and the support glass that supports it are brought into contact and bonded together. , a laminate in which both glasses are superimposed. Patent Literature 1 discloses an example of a technique for producing a laminate.

In this method, as shown in FIG. 7, a glass plate 200 is placed on a surface plate 100, and a support glass 400 having four corners supported by spacers 300 is spaced above the glass plate 200. Deploy. Then, as indicated by an arrow F, the center portion of the support glass 400 is pressed from above to bring the support glass 400 into contact with the center portion of the glass plate 200 while curving and deforming the support glass 400 downwardly convexly. As a result, the center portions of both glasses 200 and 400 become starting points for bonding, and the regions bonded together radially expand from the starting points, thereby producing a laminate in which both glasses 200 and 400 are superimposed. be.

JP 2014-129189 A

In the above method, as shown in FIG. 8, the glass plate 200 placed on the platen 100 may warp due to the flexibility of the glass plate 200 . Due to the existence of this warp, there is a problem that a part of the glass plate 200 bonded to the support glass 400 rises from the support glass 400 and becomes wrinkled. This is because, originally, the bonded area should expand radially from the starting point, but unintended portions are bonded first due to unevenness of the glass plate 200 due to warping.

A technical problem to be solved in view of the above-mentioned circumstances is that, when manufacturing a flexible thin glass plate includes a step of bonding the glass plate to a support glass to produce a laminate, To enable bonding while avoiding the occurrence of wrinkles.

A method for manufacturing a glass plate for solving the above-mentioned problems is to bring the surfaces of a flexible glass plate placed on a stage and a support glass that supports the glass plate into contact with each other to bond the two glasses together. A method including a lamination step of fabricating a laminated body in which both glasses are superimposed by radially enlarging a region from the starting point of lamination. In the lamination step, the glass plate was sucked by a negative pressure from a stage. It is characterized by bonding both glasses together in a state.

In this method, by sucking the glass plate with a negative pressure from the stage in the lamination process, it is possible to correct the warp existing in the glass plate so as to follow the stage. Then, the glass plate and the support glass can be bonded together in a state where the warp (unevenness) is removed from the glass plate. As a result, it is possible to reliably expand the region in which the two glasses are bonded together radially from the starting point of the bonding. As a result, it is possible to prevent unintended portions from being attached first, and to avoid wrinkles caused by part of the glass plate rising from the support glass.

In the above method, it is preferable to perform the adjustment step of adjusting the position of the glass plate on the stage while the glass plate is sucked by the negative pressure from the stage before the lamination step is performed.

In this way, the glass plate is sucked by the negative pressure from the stage, and the position is adjusted in a state in which the warpage of the glass plate is removed. It is possible to improve the accuracy of bonding.

In the above method, it is preferable to interpose a protective sheet having air permeability between the stage and the glass plate.

By doing so, it becomes easier to bond the glass plate and the support glass together. When bonding both glasses together, it is necessary to make the force with which the stage tries to attract the glass plate by negative pressure (hereinafter referred to as suction force) to be smaller than the force with which the glass plate tries to stick to the support glass. . If a protective sheet having air permeability is interposed between the stage and the glass plate, the suction force can be suppressed compared to the case where it is not interposed, and the suction force becomes excessive enough to hinder the smooth bonding of both glasses. can be suppressed. As a result, it becomes easier to bond the glass plate and the support glass together. In addition, since the suction force can be suppressed as described above, it becomes easier to move the glass plate on the stage when performing the adjustment process, and it becomes easier to adjust the position of the glass plate. Furthermore, the presence of the protective sheet prevents the glass plate from being damaged by rubbing against the stage when the glass plate is moved for position adjustment.

In the above method, it is preferred that the protective sheet is fixed to the stage.

By doing so, it is possible to prevent the protective sheet from being displaced accompanying the movement of the glass plate when performing the adjustment step, and it is possible to smoothly adjust the position of the glass plate. .

In the above method, the hardness of the protective sheet is preferably lower than that of the glass plate. Here, "the hardness of the protective sheet is lower than that of the glass plate" means that the material constituting the protective sheet does not contain a material with the same Mohs hardness as the glass plate or a higher Mohs hardness than the glass plate. means

By doing so, it is possible to reliably avoid damage to the glass plate due to contact with the protective sheet.

In the above method, the protective sheet preferably has a thickness of 100 μm or less.

In this way, since the thickness of the protective sheet is sufficiently thin, it becomes easy to ensure the flatness of the glass plate when it overlaps with the protective sheet, and the glass plate and the support glass are bonded together without wrinkles. is more advantageous in realizing

In the above method, the protective sheet preferably has a surface roughness Ra of 25 nm or more.

By doing so, when the glass plate is moved on the stage in accordance with the execution of the adjusting process, it is possible to make the sliding between the glass plate and the protective sheet suitable for the movement of the glass plate.

In the above method, the glass plate may have a film formed on the back surface of the surface to be bonded to the supporting glass.

A glass plate on which a film is formed is likely to be warped. Therefore, if the method according to the present disclosure is applied to fabricate a laminate by bonding a glass plate on which a film has been formed to a support glass, the effect can be favorably enjoyed.

According to the method for manufacturing a glass plate according to the present disclosure, when manufacturing a thin glass plate having flexibility includes a step of bonding the glass plate to a support glass to produce a laminate, wrinkles may occur. It is possible to perform lamination while avoiding the occurrence of

FIG. 4 is a side view showing an adjustment step included in the method of manufacturing the glass plate; It is a side view which shows the lamination process included in the manufacturing method of a glass plate. It is a side view which shows the lamination process included in the manufacturing method of a glass plate. It is a side view which shows the lamination process included in the manufacturing method of a glass plate. It is sectional drawing which expands and shows the periphery of the surface plate and protective sheet which are used for the manufacturing method of a glass plate. FIG. 2 is a plan view showing a surface plate and a protective sheet used in the method of manufacturing a glass plate; It is a figure for demonstrating the subject in the former. It is a figure for demonstrating the subject in the former.

Hereinafter, a method for manufacturing a glass plate according to an embodiment will be described with reference to the accompanying drawings. Note that the X direction, Y direction, and Z direction shown in each drawing referred to in the description of the embodiments are directions orthogonal to each other.

In this manufacturing method, as shown in chronological order in FIGS. It includes a step of producing a laminate 3 in which the glasses 1 and 2 are superimposed.

Specifically, the above steps include an adjustment step P1 (FIG. 1) for adjusting the position of the glass plate 1 on the platen 4 as a stage before bonding the glass plate 1 and the support glass 2 together, and an adjustment step. After execution of P1, a lamination step P2 (FIGS. 2 to 4) is included in which the mating surfaces 1a and 2a of the glass plate 1 and the supporting glass 2 are brought into contact with each other to bond the two glasses 1 and 2 together.

Both glasses 1 and 2 can be made of various materials such as soda-lime glass and alkali-free glass.

In each of the glasses 1 and 2, the mating surfaces 1a and 2a, which are surfaces to be bonded to each other, have a surface roughness Ra (arithmetic mean roughness) of 1.0 nm or less. The surface roughness Ra can be controlled, for example, by polishing the two glasses 1 and 2 or by chemical etching. Specifically, by adjusting the number of polishing pads, the concentration of the etching liquid, the liquid temperature, the processing time, and the like. controlled. Note that the smaller the value of the surface roughness Ra of the mating surfaces 1a and 2a, the easier it is for both surfaces to adhere when the mating surfaces 1a and 2a are bonded together, so the surface roughness Ra should be 0.5 nm or less. is more preferable, and 0.2 nm or less is most preferable.

Although the shape of both glasses 1 and 2 is not particularly limited, both glasses 1 and 2 in this embodiment are formed in a rectangular shape. The thickness of the glass plate 1 is set to 200 μm or less. The support glass 2 is thicker than the glass plate 1, and the thickness of the support glass 2 is set to 300 μm to 2000 μm. The glass plate 1 is formed with a film (for example, an ITO film or the like) on the back side of the mating surface 1a. In this embodiment, the glass plate 1 is warped due to the influence of the film formation, and unevenness is formed on the glass plate 1 . The magnitude of warpage may be greater than the thickness of the glass plate 1 (for example, 1.5 mm to 3 mm). The term "warp" as used herein refers to the dimension of the edge of the glass plate 1 lifted from the platen 4 when the glass plate 1 is placed on the platen 4 (the dimension lifted from the mounting surface 4a described later). is the maximum value of Note that, unlike the present embodiment, the glass plate 1 may be non-film-formed, and warpage may occur even in the non-film-formed case.

The area of the support glass 2 is larger than the area of the glass plate 1 . That is, the mating surface 2a has a larger area than the mating surface 1a, and when the two glasses 1 and 2 are bonded together, the edge of the support glass 2 protrudes from the edge of the glass plate 1. As shown in FIG.

Here, an overview of equipment for executing the adjustment process P1 and the lamination process P2 will be described with reference to FIGS. 1 to 4. FIG.

The surface plate 4 is a workbench for performing both processes P1 and P2, and is made of metal in this embodiment. The platen 4 has a mounting surface 4a on which the glass plate 1 is mounted, and the mounting surface 4a is formed as a horizontal flat surface. A protective sheet 5 having air permeability is fixed on the mounting surface 4a, and the protective sheet 5 is interposed between the glass plate 1 and the platen 4 when both steps P1 and P2 are performed. The surface plate 4 is capable of exerting a suction force on the glass plate 1 through the protective sheet 5 by negative pressure during execution of both steps P1 and P2 as indicated by an arrow F1 (details will be described later).

As an example, the protective sheet 5 is made of a material such as paper, polyethylene terephthalate, or resin such as highly foamed polyethylene. The hardness of the protective sheet 5 is lower than that of the glass plate 1. - 特許庁This is for the purpose of preventing the glass plate 1 from being damaged by contact with the protective sheet 5 . Here, "the hardness of the protective sheet 5 is lower than the hardness of the glass plate 1" means that the material constituting the protective sheet 5 has the same Mohs hardness as the glass plate 1 or a higher Mohs hardness than the glass plate 1. This means that it does not contain hard materials. Moreover, the thickness of the protective sheet 5 is set to 100 μm or less. This is for the purpose of making it easy to ensure the flatness of the glass plate 1 when it overlaps with the protective sheet 5 . The thickness of the protective sheet 5 is preferably 80 μm or less. Furthermore, the surface roughness Ra of the protective sheet 5 is set to 25 nm or more. This is for the purpose of making the sliding between the glass plate 1 and the protective sheet 5 suitable when the adjustment step P1 is performed. Also, the surface roughness Ra of the protective sheet 5 can be set to, for example, 150 nm or less.

Four spacers 6 are arranged on the mounting surface 4a of the platen 4 (only two are shown in FIGS. 1 to 4), and are arranged on the mounting surface 4a on the outer peripheral side of the glass plate 1. are placed. Each spacer 6 functions as a support member that supports the corner portions of the support glass 2 from below, and the four spacers 6 are arranged so as to correspond to the four corners of the support glass 2 . A support glass 2 supported by four spacers 6 is arranged with a space therebetween above the glass plate 1 on the platen 4 . Further, the support glass 2 is supported by spacers 6 in a state in which bending deformation is allowed.

Although the spacer 6 is used as the supporting member in this embodiment, the supporting member is not limited to this. Any member may be used as the supporting member as long as the following conditions (1) and (2) are satisfied. (1) It is possible to support the support glass 2 while facing the glass plate 1 on the platen 4 with a gap therebetween. (2) It is possible to support the edge of the supporting glass 2 while allowing the curved deformation of the supporting glass 2 . As a member that satisfies the above conditions (1) and (2), for example, a frame-shaped member that supports the four sides of the rectangular support glass 2 may be used as the support member, or only two opposite sides of the support glass 2 may be used as the support member. may be used as the supporting member.

Here, the details of the mechanism by which the platen 4 applies the suction force F1 to the glass plate 1 via the protective sheet 5 will be described with reference to FIGS. 5 and 6. FIG.

A plurality of suction holes 4b for sucking the glass plate 1 are formed in the mounting surface 4a of the platen 4. As shown in FIG. The suction holes 4b are arranged along the X direction and the Y direction. The area of the region where the suction holes 4b are formed on the mounting surface 4a is larger than the area of the glass plate 1. As shown in FIG. Each suction hole 4b is connected to a negative pressure generating device (for example, a vacuum pump, etc.), not shown, and the negative pressure is applied to the glass plate 1 through the protective sheet 5 by the operation of the device to suck the glass plate 1 .

The protective sheet 5 is attached to the mounting surface 4a of the platen 4 with a tape 7 (not shown in FIGS. 1 to 4). A plurality of through-holes 5a are formed in the protective sheet 5 so as to penetrate the protective sheet 5 in the thickness direction (Z direction), and the through-holes 5a provide the protective sheet 5 with air permeability. The through holes 5a are arranged along the X direction and the Y direction. The area of the protective sheet 5 where the through holes 5 a are formed is larger than the area of the glass plate 1 . This allows the surface plate 4 to suck the entire glass plate 1 through the protective sheet 5 .

The shape of the suction hole 4b of the platen 4 and the through hole 5a of the protective sheet 5 may be circular or may be other than circular. Further, the positions of the suction holes 4b of the surface plate 4 and the positions of the through holes 5a of the protective sheet 5 do not need to match. The maximum diameter of the suction hole 4b of the surface plate is set to 1 mm to 10 mm. Further, the maximum diameter of the through holes 5a of the protective sheet 5 is set to 1 μm to 1 mm. The maximum diameter of the suction hole 4b and the through hole 5a means the maximum length of a straight line passing through the center of gravity of the suction hole 4b and the through hole 5a (for example, the shape of the hole is elliptical). , the longest diameter is the maximum diameter). The number of suction holes 4b in the surface plate 4 and the number of through holes 5a in the protective sheet 5 can be set according to the thickness of the glass plate 1. FIG. For example, when the thickness of the glass plate 1 is 100 μm or more, the number of the suction holes 4b in the platen 4 is larger than the number of the through holes 5a in the protective sheet 5 in order to strongly attract the glass plate 1 to the platen 4. It is preferable that the positions of the suction holes 4b of the surface plate 4 coincide with the positions of the through holes 5a of the protective sheet 5. As shown in FIG. On the other hand, when the thickness of the glass plate 1 is less than 100 μm, a protective sheet 5 made of a porous resin or the like is used in order to apply a suction force to the entire glass plate 1, or the through holes of the protective sheet 5 are used. It is preferable to make the number of the suction holes 5a larger than the number of the suction holes 4b of the surface plate 4. FIG. This makes it easier to bond the glass plate 1 and the support glass 2 together.

Specific procedures of a method for manufacturing a glass plate using the above equipment will be described below.

First, the adjustment step P1 shown in FIG. 1 is performed. In the adjustment step P1, the glass plate 1 is slid on the protective sheet 5 while the glass plate 1 is sucked by the negative pressure from the surface plate 4. As shown in FIG. Thereby, the position of the glass plate 1 on the platen 4 is adjusted in the X direction and the Y direction (adjustment in the X direction is illustrated in FIG. 1). At this time, the strength of the suction force F1 with which the surface plate 4 tries to attract the glass plate 1 due to the negative pressure is the strength that can correct the warp generated in the glass plate 1 so as to follow the mounting surface 4a of the surface plate 4. and the strength is adjusted so that the glass plate 1 can be slid on the protective sheet 5. - 特許庁The adjustment process P1 is completed by the above.

After the adjustment process P1 is completed, the stacking process P2 shown in FIGS. 2 to 4 is performed. In the stacking step P2, first, as shown in FIG. 2, the support glass 2 is placed on the spacers 6 after adjusting the corners of the support glass 2 to be positioned on each of the four spacers 6 . Even when the support glass 2 is placed on the spacer 6, the surface plate 4 continues to suck the glass plate 1. As shown in FIG. The support glass 2 placed on the spacer 6 is capable of bending deformation (elastic deformation) on the spacer 6 due to an external force applied to the support glass 2 or its own weight.

After the supporting glass 2 is placed on the spacer 6, the central portion of the supporting glass 2 is pressed from above as indicated by the arrow F2 in FIG. . Then, the central portion 1ax of the mating surface 1a of the glass plate 1 and the central portion 2ax of the mating surface 2a of the support glass 2 are brought into contact with each other. As a result, the central portions 1ax and 2ax that are in contact with each other become starting points for bonding. Even when the center portions 1ax and 2ax are brought into contact with each other, the suction of the glass plate 1 by the platen 4 continues. Here, in this embodiment, the central portion of the support glass 2 is pressed from above, but as a modification, a portion other than the central portion (an arbitrary portion inside the end portion) is pressed from above. good too. In this case, a location other than the center portions 1ax and 2ax becomes the starting point of bonding.

After the central portions 1ax and 2ax are brought into contact with each other as described above, the region where the two glasses 1 and 2 are bonded radially expands around the starting point, thereby forming the laminate shown in FIG. 3 is produced. Incidentally, when the bonded area expands, each part of the glass plate 1 which is in a state of being sucked by the surface plate 4 gradually rises to the side of the supporting glass 2 and sticks thereon. At this time, the strength of the suction force F1 with which the surface plate 4 tries to suck the glass plate 1 due to the negative pressure is made weaker than the adhesion force with which each part of the glass plate 1 sticks to the support glass 2. adjusted. The lamination process P2 is completed by the above.

Here, it is also possible to apply the following modifications to the above embodiment. In the above embodiment, the glass plate 1 is arranged relatively downward and the support glass 2 is arranged relatively upward, but the arrangement of both glasses 1 and 2 is reversed from that of this embodiment. may However, considering the handling of the flexible glass plate 1, the arrangement in the above embodiment is preferable.

REFERENCE SIGNS LIST 1 glass plate 1a mating surface 1ax central portion 2 supporting glass 2a mating surface 2ax central portion 3 laminate 4 surface plate (stage)
5 Protective sheet P1 Adjustment process P2 Lamination process

Claims (8)

By bringing the surfaces of a flexible glass plate placed on a stage and a support glass that supports the glass plate into contact with each other, and expanding the area where the two glasses are bonded together radially from the starting point of the bonding. , a method for producing a glass plate including a lamination step of producing a laminate in which the two glasses are superimposed,
The method for producing a glass plate, wherein in the laminating step, the glass plates are adhered to each other while the glass plate is being sucked by a negative pressure from the stage. 2. An adjusting step of adjusting the position of the glass plate on the stage while the glass plate is sucked by a negative pressure from the stage before the stacking step is performed. The method for producing the glass plate according to 1. 3. The method of manufacturing a glass plate according to claim 1, wherein a protective sheet having air permeability is interposed between the stage and the glass plate. 4. The method of manufacturing a glass plate according to claim 3, wherein the protective sheet is fixed to the stage. 5. The method for producing a glass plate according to claim 3, wherein the protective sheet has a hardness lower than that of the glass plate. 6. The method for producing a glass plate according to claim 3, wherein the protective sheet has a thickness of 100 μm or less. 7. The method for producing a glass plate according to claim 3, wherein the protective sheet has a surface roughness Ra of 25 nm or more. The method for producing a glass plate according to any one of claims 1 to 7, wherein the glass plate has a film formed on the back surface of the surface to be bonded to the supporting glass.

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