阅读说明：本技术 玻璃基板的处理方法及化学强化玻璃基板 (Glass substrate processing method and chemically strengthened glass substrate ) 是由 藤原祐辅 于 2020-08-28 设计创作，主要内容包括：本发明涉及玻璃基板的处理方法及化学强化玻璃基板,玻璃基板的处理方法具备如下工序：准备具有互相对向的一对主面且上述主面的面积A与上述一对主面彼此之间的厚度t的比A/t为25000以上的玻璃基板的工序、将上述玻璃基板以上述主面与铅垂方向大致平行的朝向保持于玻璃收容部的工序及使上述玻璃基板保持于上述玻璃收容部的状态不变并对上述玻璃基板进行液体处理的工序,上述玻璃收容部具备：玻璃支承部,利用第一支承部件及第二支承部件支承所述玻璃基板；及引导部件,分别设置于被上述玻璃支承部支承的上述玻璃基板的厚度方向上的一侧和另一侧。(The invention relates to a method for processing a glass substrate and a chemically strengthened glass substrate, wherein the method for processing the glass substrate comprises the following steps: a step of preparing a glass substrate having a pair of main surfaces facing each other and a ratio a/t of an area a of the main surfaces to a thickness t between the pair of main surfaces being 25000 or more, a step of holding the glass substrate in a glass accommodating portion in an orientation in which the main surfaces are substantially parallel to a vertical direction, and a step of performing liquid processing on the glass substrate while keeping the glass substrate in the glass accommodating portion, the glass accommodating portion including: a glass support unit for supporting the glass substrate by a first support member and a second support member; and guide members provided on one side and the other side in the thickness direction of the glass substrate supported by the glass support unit.)

1. A method for processing a glass substrate, comprising the steps of:

preparing a glass substrate having a pair of main surfaces facing each other, wherein a ratio A/t of an area A of the main surfaces to a thickness t between the pair of main surfaces is 25000 or more;

holding the glass substrate in a glass housing portion in an orientation in which the main surface is substantially parallel to the vertical direction; and

performing liquid treatment on the glass substrate while keeping the glass substrate in the glass accommodating portion,

the glass accommodating portion includes:

a glass support portion for supporting the glass substrate by a first support member for locking a lower side peripheral edge portion of the glass substrate which is located below in a vertical direction and a second support member for locking an upper side peripheral edge portion of the glass substrate which is located above in the vertical direction with respect to the lower side peripheral edge portion; and

guide members provided on one side and the other side in the thickness direction of the glass substrate supported by the glass support portion,

the guide member is separated from the main surface of the glass substrate when the glass substrate is flat,

when the glass substrate is deflected, the guide member contacts the main surface on the convex side of the glass substrate before the locking between the glass substrate and at least one of the first support member and the second support member is released, thereby suppressing deflection of the glass substrate.

2. The method for processing a glass substrate according to claim 1,

the thickness of the glass substrate is less than 0.2 mm.

3. The method for processing a glass substrate according to claim 1 or 2,

the guide member is formed by bending a wire.

4. The method for processing a glass substrate according to any one of claims 1 to 3, wherein,

the first support member and the second support member have support recesses each having a width larger than the thickness of the glass substrate, and the glass substrate is supported by being inserted into a peripheral edge portion of the glass substrate in the support recesses.

5. The method for processing a glass substrate according to claim 4, wherein,

the guide member extends from a peripheral edge portion of the glass substrate toward a center of the main surface so as to be deeper than the groove of the support concave portion.

6. The method for processing a glass substrate according to claim 4 or 5, wherein,

the first support member and the second support member have a plurality of support recesses formed in the longitudinal direction thereof,

the glass housing portion is formed by erecting the first support member and the second support member in one direction on a box main body formed in a frame shape or a box shape,

the plurality of glass substrates are held in the support concave portions of the first support member and the support concave portions of the second support member so as to be separated from each other.

7. The method for processing a glass substrate according to claim 6, wherein,

a stopper member for preventing the glass substrates from floating up is provided above the plurality of glass substrates of the cassette main body.

8. The method for processing a glass substrate according to any one of claims 4 to 7, wherein,

the groove width of the support recess in the thickness direction of the glass substrate is 1.5 times or more and 3 times or less the thickness of the glass substrate.

9. The method for processing a glass substrate according to any one of claims 4 to 8, wherein,

the arrangement interval of the glass substrate along the thickness direction of the glass substrate is in the range of 0.00006 to 0.0006 times of the value A/t obtained by dividing the area A of the main surface of the glass substrate by the thickness t between the pair of main surfaces.

10. The method for processing a glass substrate according to any one of claims 4 to 9, wherein,

the guide members are arranged at an interval in the thickness direction of the glass substrate, which is greater than the groove width of the support recess and is not more than 5000 times the thickness of the glass substrate.

11. The method for processing a glass substrate according to any one of claims 4 to 10, wherein,

the position of the guide member in the vertical direction is within a range from a lower edge of the glass substrate to a height of 45% or more of a width of the glass substrate in the vertical direction and a height of 95% or less of the width of the glass substrate in the vertical direction.

12. The method for processing a glass substrate according to any one of claims 4 to 11, wherein,

the guide member projects from one side edge of the glass substrate toward the other side edge by an amount of 20% or more of the horizontal width of the glass substrate.

13. The method for processing a glass substrate according to claim 11 or 12, wherein,

the pair of guide members is provided so as to extend from one side edge and the other side edge of the glass substrate toward the center of the main surface of the glass substrate.

14. The method for processing a glass substrate according to any one of claims 1 to 13, wherein,

the step of performing the liquid treatment is a step of performing a chemical strengthening treatment on the glass substrate.

15. The method for processing a glass substrate according to claim 14, wherein,

the first and second support members and the guide member are formed of a stainless steel material.

16. The method for processing a glass substrate according to claim 14 or 15, wherein,

a lower guide member disposed below the guide member is further provided within a range of a height of less than 45% of a width of the glass substrate in a vertical direction from a lower side of the glass substrate.

17. The method for processing a glass substrate according to any one of claims 1 to 13, wherein,

the liquid treatment step includes a chemical liquid treatment step involving a flow of a liquid performed after the chemical strengthening treatment, and a cleaning step performed in the chemical liquid treatment step.

18. The method for processing a glass substrate according to claim 17, wherein,

at least the surfaces of the first support member, the second support member, and the guide member are made of a resin material.

19. The method for processing a glass substrate according to claim 18, wherein,

the resin material is fluorine-containing resin.

20. The method for processing a glass substrate according to any one of claims 17 to 19, wherein,

in a two-dimensional projection image in which the guide member is projected from the thickness direction of the glass substrate supported by the glass support portion to the main surface of the glass substrate and the region where the guide member overlaps the main surface of the glass substrate is indicated by hatching,

a total width of shadow existing regions in a one-dimensional shadow vertical distribution in which shadows of the projection image are projected to vertical sides of the glass substrate in a horizontal direction of the glass substrate is 50% or more of a width of the glass substrate in a vertical direction,

the total width of shadow existing regions in a one-dimensional shadow horizontal distribution formed by projecting the shadow of the projected image to the horizontal side of the glass substrate in the vertical direction of the glass substrate is 50% or more of the width of the glass substrate in the horizontal direction.

21. The method for processing a glass substrate according to claim 20, wherein,

the shadow existence region in the shadow vertical distribution and the shadow horizontal distribution includes a center of a main surface of the glass substrate.

22. A chemically strengthened glass substrate is provided,

has a pair of main surfaces facing each other,

the ratio A/t of the area A of the main surface to the thickness t between the pair of main surfaces is 25000 or more,

the difference between the value of the compressive stress of one of the pair of main surfaces and the value of the compressive stress of the other main surface is 10MPa or less.

23. The chemically strengthened glass substrate according to claim 22,

the ratio A/t between the area A of the main surface and the thickness t between the pair of main surfaces is 100000 or more.

24. The chemically strengthened glass substrate according to claim 22 or 23, wherein,

the difference between the depth of the compressive stress layer in one of the pair of main surfaces and the depth of the compressive stress layer in the other main surface is 0.1 μm or less.

25. The chemically strengthened glass substrate according to any one of claims 22 to 24, wherein,

the thickness t between the pair of main surfaces is 0.2mm or less.

26. The chemically strengthened glass substrate according to any one of claims 22 to 25, wherein,

the values of the compressive stresses on the pair of main surfaces are 600MPa or more, and the depths of the compressive stress layers on the pair of main surfaces are 3 μm to 30 μm, respectively.

Technical Field

The invention relates to a glass substrate processing method and a chemically strengthened glass substrate.

Background

In a flat panel display device used in a Personal Digital Assistant (PDA) or a portable computer, a thin plate-like cover glass is disposed in front of a display. Such cover glass is produced through various liquid processing steps such as chemical strengthening, chemical treatment, HF etching, and ultrasonic cleaning.

In the liquid treatment steps, the cover glass is treated while being held in the cassette. However, as the cover glass is made thinner, it is difficult to stably hold the glass, particularly in the case of a thin glass sheet having a thickness of 0.2mm or less.

For example, when a cover glass is held by using a conventional cassette as described in patent documents 1 and 2, the cover glass may be bent by its own weight or an external force, and the glass surface may be pushed against surrounding members to be damaged, or the cover glass may be detached from the cassette or damaged.

Therefore, a method of applying an external force to a thin glass sheet to bend the thin glass sheet and performing liquid treatment while keeping the bent state is known (patent documents 3 and 4). In the method, the following operations are carried out: a flat glass sheet having an initial shape is prepared, and the glass sheet is bent from the initial shape to a bent second shape by a load of stress. The bent glass sheet is then left under stress for subsequent processing to maintain the second shape. After subsequent processing, the load stress is relieved and at least a portion of the glass sheet returns to the original shape.

Documents of the prior art

Patent document

Patent document 1: japanese patent No. 5730241

Patent document 2: international publication No. 2008/078492

Patent document 3: japanese patent laid-open publication No. 2016-529196

Patent document 4: japanese patent No. 6392363

Disclosure of Invention

Problems to be solved by the invention

However, in the method of patent document 3, when the glass substrate is subjected to the chemical strengthening treatment, there are problems that a stress difference occurs on the front and back surfaces of the glass substrate and the glass substrate is deformed. In addition, in the cleaning process of the glass substrate, the holding force in the flowing liquid is insufficient in the above method, and the glass substrate is damaged. In the method of patent document 4, the bending of the glass sheet is controlled by a jig having an adjusting screw unit, and only one of the principal surfaces of the glass base material is subjected to asymmetric ion exchange to perform chemical strengthening.

The invention aims to provide a method for processing a glass substrate, which can stably manufacture a glass substrate with high yield and suppressed deformation of the processed glass by maintaining the state of stably holding a glass plate in a plate surface and implementing various processing procedures without affecting the quality of the glass.

A second object of the present invention is to provide a chemically strengthened glass substrate in which cracks and warpage are suppressed.

Means for solving the problems

The present invention is constituted by the following structure.

The glass substrate processing method comprises the following steps:

preparing a glass substrate having a pair of main surfaces facing each other, wherein a ratio A/t between an area A of the main surfaces and a thickness t between the pair of main surfaces is 25000 or more;

holding the glass substrate in a glass accommodating portion in an orientation in which the main surface is substantially parallel to the vertical direction; and

performing liquid treatment on the glass substrate while keeping the glass substrate in the glass accommodating portion,

the glass storage unit includes:

a glass support portion for supporting the glass substrate by a first support member for locking a lower side peripheral edge portion of the glass substrate below in a vertical direction and a second support member for locking an upper side peripheral edge portion of the glass substrate above in the vertical direction; and

guide members provided on one side and the other side in the thickness direction of the glass substrate supported by the glass support portion,

when the glass substrate is flat, the guide member is separated from the main surface of the glass substrate,

when the glass substrate is deflected, the guide member contacts the main surface on the convex side of the glass substrate before the engagement between the glass substrate and at least one of the first support member and the second support member is released, thereby suppressing the deflection of the glass substrate.

A second aspect of the present invention is constituted by the following configuration.

A chemically strengthened glass substrate is provided,

has a pair of main surfaces facing each other,

the ratio A/t of the area A of the main surface to the thickness t between the pair of main surfaces is 25000 or more,

the difference between the value of the compressive stress of one of the pair of main surfaces and the value of the compressive stress of the other main surface is 10MPa or less.

Effects of the invention

According to the present invention, various processing steps can be performed while maintaining a state in which a glass sheet is stably held in a sheet surface without affecting the quality of the glass. This enables to stably manufacture a glass substrate in which deformation of the glass after the treatment is suppressed with high yield.

Further, according to the second aspect of the present invention, a chemically strengthened glass substrate in which cracks and warpage are suppressed can be provided.

Drawings

FIG. 1 is a schematic block diagram illustrating a method for processing a glass substrate according to the present invention.

Fig. 2 is a schematic perspective view schematically showing a cassette of a first configuration example used in a chemical strengthening treatment process of a glass substrate.

Fig. 3 is a schematic plan view of the cartridge according to the first configuration example.

Fig. 4 is a schematic front view of the cartridge of the first configuration example shown in fig. 2, as viewed from the X direction.

Fig. 5 is a plan view of a main portion showing a positional relationship between the guide member and the glass substrate at the time of deformation.

Fig. 6 (a) is a plan view of a main portion of the cartridge showing the arrangement of the guide members in the first modification, and fig. 6 (B) is a plan view of a main portion of the cartridge showing the arrangement of the guide members in the second modification.

Fig. 7 (a) is a front view of a cartridge showing the arrangement of guide members of a third modification, fig. 7 (B) is a front view of a cartridge showing the arrangement of guide members of a fourth modification, fig. 7 (C) is a front view of a cartridge showing the arrangement of guide members of a fifth modification, and fig. 7 (D) is a front view of a cartridge showing the arrangement of guide members of a sixth modification.

Fig. 8 is a perspective view of a cartridge of a seventh modification.

Fig. 9 (a) is a plan view of a main portion of the glass support portion supporting the groove having the V-shaped concave portion, and fig. 9 (B) is a plan view of a main portion of the glass support portion supporting the groove having the concave portion.

Fig. 10 is a plan view of a main portion showing a dimensional relationship between the pair of second supporting members and the glass substrate.

Fig. 11 is a schematic perspective view schematically showing a cartridge according to a second configuration example used in a chemical liquid processing step of a glass substrate.

Fig. 12 is a cross-sectional view of the guide member of the second configuration example in the direction orthogonal to the axis.

Fig. 13 is a schematic plan view of the cartridge according to the second configuration example.

Fig. 14 is a schematic front view of the cartridge of the second configuration example as viewed from the X direction.

Fig. 15 is an explanatory view schematically showing a two-dimensional projection image in which a region where the guide member overlaps the main surface of the glass substrate is hatched.

Description of the reference symbols

11 chemical strengthening step (chemical strengthening treatment step)

13 cleaning step (chemical strengthening treatment step)

15 acid treatment step (liquid treatment step)

17 alkali treatment step (chemical solution treatment step)

19 cleaning step (chemical solution treatment step)

21 glass substrate

23. 51 guide member

25. 45 boxes

25A box

27. 53 Box body

29 glass container

31 glass support

33 lower edge

34 upper side

35. 47 first support member

37 upper side peripheral edge portion

38 side edge

39. 49 second support member

41 support recess

41A groove (bearing concave part)

43 position limiting component

55 core material

57 resin material

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

The glass substrate processing method of the present invention includes the following steps.

(1) And preparing a glass substrate having a pair of main surfaces facing each other, wherein the ratio A/t between the area A of the main surfaces and the thickness t between the pair of main surfaces is 25000 or more.

(2) And a step of holding the glass substrate in the glass accommodating portion in an orientation in which the main surface is substantially parallel to the vertical direction.

(3) And a step of performing liquid treatment on the glass substrate while keeping the glass substrate in the glass accommodating portion.

The glass container used in each of the above-described steps includes a glass support portion and a guide member.

The glass support portion has a first support member that engages a lower side peripheral edge portion of the glass substrate below in the vertical direction and a second support member that engages an upper side peripheral edge portion of the glass substrate above in the vertical direction.

The guide members are provided on one side and the other side in the thickness direction of the glass substrate supported by the glass support portion.

According to the structure of the glass housing portion, when the main surface of the glass substrate is flat, the guide member is separated from the main surface of the glass substrate. On the other hand, when the main surface of the glass substrate 21 is displaced in the thickness direction to be curved while the lower and upper peripheral edge portions of the glass substrate are supported by the glass support portion (hereinafter, this displaced state will be described as "deflection" of the glass substrate 21), the guide member comes into contact with the convex main surface of the glass substrate before the engagement between the glass substrate and at least one of the first support member and the second support member is released. This can suppress the deflection of the glass substrate.

According to the method of processing a glass substrate using the glass containing unit, the glass substrate is supported by the first support member due to its own weight, and is held in an upright posture by the second support member restricting the tilt of the glass substrate to either one of the main surfaces. In addition, the main surface of the glass substrate, which is suppressed from being bent, is suppressed from being pressed against surrounding members by the guide member, and is less likely to be damaged. Further, the glass substrate is prevented from being detached from the glass support portion by bending and from falling off the glass accommodating portion and being damaged (broken). As a result, the easily deformable thin glass sheet can be stably supported while suppressing deformation after processing. Further, since the glass substrate does not contact peripheral members other than the glass support portion when the glass substrate is flat, the effects of chemical strengthening, cleaning, and chemical treatment are not impaired.

Next, an embodiment of the present invention described above will be explained below.

< first configuration example >

FIG. 1 is a schematic block diagram illustrating a method for processing a glass substrate according to the present invention.

The method of processing a glass substrate exemplified here is roughly divided into a chemical strengthening treatment step and a chemical treatment step. The chemical strengthening treatment step is further divided into a chemical strengthening step 11 and a cleaning step 13. The chemical liquid treatment step is further divided into an acid treatment step 15, an alkali treatment step 17, and a cleaning step 19.

In a glass substrate processing method including a chemical strengthening step 11 using an inorganic salt containing a predetermined salt, a cleaning step 13 after the chemical strengthening step 11, water rinsing in an acid treatment step 15, water rinsing in an alkali treatment step 17, and a cleaning step 19 after the alkali treatment step are generally performed for the purpose of improving the cleanliness of glass. These cleaning treatments may be ultrasonic cleaning by applying ultrasonic waves.

The method for treating a glass substrate of the present invention comprises a chemical strengthening step 11, wherein the chemical strengthening step 11 is carried out by mixing a glass containing sodium with a glass containing potassium nitrate and potassium nitrate₂CO₃、Na₂CO₃、KHCO₃、NaHCO₃、K₃PO₄、Na₃PO₄、K₂SO₄、Na₂SO₄And an inorganic salt of at least one salt selected from the group consisting of KOH and NaOH, thereby performing ion exchange between Na in the glass to be treated and K in the inorganic salt. The glass substrate processing method includes an acid treatment step 15 of subjecting the glass to be processed to acid treatment after the chemical strengthening step 11, an alkali treatment step 17 of subjecting the glass to alkali treatment after the acid treatment step 15, and the above-described cleaning steps 13 and 19.

The details of the chemical strengthening treatment and the chemical solution treatment are the same as those of japanese patent application laid-open nos. 2019-6615 and 2019-6650, for example, and therefore, it is desirable to appropriately refer to these treatments as needed.

The step of performing the liquid processing using the cartridge of the first configuration example described below is a step of performing a chemical strengthening process on the glass substrate 21.

The chemical strengthening step has the following specific problems.

Since the glass substrate 21 is processed in the molten salt, chemical resistance is required for a supporting member for supporting the glass substrate 21. Further, the salt accumulated between the support member and the glass substrate 21 becomes dirt and adheres to the support member. Further, since the glass substrate 21 is processed in a high temperature atmosphere of about 400 ℃, it is necessary to select a heat-resistant material for the support member. Further, at the time of temperature reduction after the high-temperature treatment, a temperature difference is generated between a contact portion and a non-contact portion of the support member with the glass substrate 21 or a difference in specific gravity between the molten salt and the glass substrate 21 is small, and therefore, it is necessary to prevent the glass substrate 21 from floating in a liquid such as the molten salt.

(case and glass substrate)

Fig. 2 is a schematic perspective view schematically showing a cartridge 25 of a first configuration example used in a chemical strengthening process of a glass substrate. In fig. 2, the cassette 25 is schematically illustrated for simplifying the explanation of the cassette 25, and the number of accommodated glass substrates 21 and the size of each part are not limited thereto but arbitrary.

The glass substrate 21 used here has a pair of main surfaces facing each other. The ratio a/t of the area a of the main surface of the glass substrate 21 to the thickness t between the pair of main surfaces is 25000 or more, preferably 50000 or more, and more preferably 100000 or more.

The glass substrate 21 has a thickness of 0.2mm or less, and preferably has a thickness of 30 to 150 μm, for example. The width W and height H (see fig. 4) of the glass substrate 21 are appropriately selected according to the ratio a/t, for example, from a small glass substrate of about 50mm to 800mm to a large glass substrate exceeding 1000 mm. The glass substrate 21 shown here is a rectangle in which the widths W of the upper side 34 and the lower side 33 are equal to each other and the widths (heights H) of the pair of side edges 38 are also equal to each other, but the shape of the glass substrate 21 is not limited to this.

Here, a cassette 25 having a glass accommodating portion 29 is used, and the glass accommodating portion 29 holds a plurality of prepared glass substrates at the same time. The glass substrate 21 is held in the glass accommodating portion 29 with its principal surface oriented substantially parallel to the vertical direction. Next, the glass substrate 21 is subjected to liquid processing for each cassette 25 while maintaining the state in which the glass substrate 21 is held in the glass accommodating portion 29.

When the liquid processing is performed on the glass substrate 21, the cassette 25 accommodating the plurality of glass substrates 21 may be processed by a single body, or a plurality of cassettes 25 may be fixed to a not-shown tray to simultaneously process a plurality of glass substrate groups accommodated in the plurality of cassettes 25. In this case, the bracket may couple the cartridge 25 in the horizontal direction, or may couple the coupling cartridge 25 in the vertical direction.

The glass containing portion 29 of the cartridge 25 includes a glass support portion 31 and a guide member 23.

(glass support)

The glass support portion 31 includes a first support member 35 and a second support member 39, the first support member 35 engages a lower side 33 which is a part of a lower side peripheral edge portion of the glass substrate 21 in a lower side in the vertical direction, and the second support member 39 engages an upper side peripheral edge portion 37 including an upper side 34 and a side 38 which is above the lower side peripheral edge portion of the glass substrate 21 in the vertical direction. The plurality of glass substrates 21 are supported by the glass accommodating portion 29 with a predetermined gap between the first support member 35 and the second support member 39. Here, the lower peripheral edge means a peripheral edge below the center of the glass substrate 21 in the vertical direction.

The first support member 35 and the second support member 39 are fixed to the box main body 27 formed in a frame shape or a box shape at both ends in the longitudinal direction in a state of being stretched in one direction from one end to the other end in the X direction. That is, the first support member 35 is disposed at the bottom of the cartridge main body 27 in parallel with each other in the Y direction. The second support members 39 are disposed along the X direction at both ends of the cartridge main body 27 in the Y direction.

The first support member 35 and the second support member 39 support the plurality of glass substrates 21 in parallel while being separated from each other by locking the plurality of glass substrates 21 in any of the support concave portions 41 of the first support member 35 and the second support member 39.

In fig. 2, the first support members 35 and the second support members 39 are arranged in two rows, respectively, but may be arranged in three or more rows. The first support member 35 may be arranged only in a single row in the center of the lower side 33.

The vertical separation distance between the first support member 35 and the second support member 39 is preferably set to 60% or more, preferably 70% or more, of the height H (see fig. 4) of the glass substrate 21, and preferably 90% or less, preferably 80% or less, of the height H.

(guide member)

The guide members 23 are provided to face the principal surface on one side and the other side in the thickness direction (X direction) of the glass substrate 21 supported by the glass support portion 31. Each guide member 23 may be formed by bending a wire rod into a U-shape or a V-shape in a plan view, for example.

The first support member 35, the second support member 39, and the guide member 23 have heat resistance of 450 ℃. The first support member 35 and the second support member 39 have the same structure, and preferably have surfaces covered with a heat-resistant cushioning material such as glass fiber.

Fig. 3 is a schematic plan view of the cartridge 25 according to the first configuration example. Fig. 4 is a schematic front view of the cartridge 25 of the first configuration example viewed from the X direction. In fig. 3, the first support member 35 on the lower side of the cartridge 25 is omitted.

A support recess 41 having a groove width Pb larger than the thickness t of the glass substrate 21 is formed in the second support member 39 shown in fig. 3 (the same applies to the first support member 35). The peripheral edge portion of the glass substrate 21 is inserted into the support recess 41, and the glass substrate 21 is positioned and supported in the axial direction of the first support member 35 and the second support member 39.

The first support member 35 and the second support member 39 are each formed with a support recess 41, which is a circumferential groove having a groove depth Db, in the circumferential direction on the outer periphery of the cylindrical member. The support recesses 41 are provided at a plurality of positions along the axis of the first support member 35 and the second support member 39 so that the phases in the axial direction (X direction) are aligned with each other.

The support concave portion 41 may have another shape such as a rectangular shape, instead of the V-groove having a triangular shape in the axial cross section. The groove depth Db of the support concave portion 41 is set in accordance with the thickness t of the glass substrate 21 and the area a of the main surface. For example, the groove depth Db of the support concave portion 41 is preferably 10 times or more, more preferably 20 times or more, further preferably 30 times or more, and preferably 300 times or less, more preferably 200 times or less, further preferably 150 times or less the thickness t of the glass substrate 21.

The glass substrate 21 supported by the support recess 41 is preferably such that the arrangement interval Pt in the plate thickness direction (X direction) of the glass substrate 21 is in the range of 0.00006 to 0.0006 times the value (a/t) obtained by dividing the area a of the main surface of the glass substrate 21 by the thickness t between the pair of main surfaces. More preferably 0.00008 times or more, still more preferably 0.00010 times or more, still more preferably 0.0005 times or less, and still more preferably 0.0004 times or less. The arrangement interval Pt is preferably constant, but may be an unequal interval.

Further, the first support member 35 and the second support member 39 may be formed by machining a large-diameter cylindrical material so that the groove depth Db of the support concave portion 41 is about 50 to 100 times the thickness t of the glass substrate 21. In this case, the glass supporting function of the guide member 23 described in detail below can be exhibited depending on the use conditions.

As shown in fig. 3, the guide member 23 preferably extends (extending length Da) from the peripheral edge portion (side 38 in fig. 4) of the glass substrate 21 toward the center of the main surface so as to be longer than the groove depth Db of the support concave portion 41. The guide member 23 has, for example, a bent portion 23a at the tip end formed by bending a wire rod in a U shape and a base end portion 23b connected to the bent portion 23a, and is disposed in a virtual plane (XY plane) orthogonal to the main surfaces of the arranged glass substrates 21. The wire material of the base end portion 23b is formed in a linear shape or a curved shape spreading outward from each other in an imaginary plane.

The guide members 23 are preferably provided at a constant arrangement interval Pa in the thickness direction (X direction) of the glass substrate 21. The arrangement interval Pa is preferably longer than the groove width Pb of the support concave 41 and is 5000 times or less, more preferably 4000 times or less, and still more preferably 2500 times or less the thickness of the glass substrate 21.

By setting the arrangement interval Pa of the guide members 23 to the above range, the separation distance between the glass substrate 21 and the guide members 23 can be secured.

Fig. 4 is a schematic front view of the cartridge 25 of the first configuration example shown in fig. 2, as viewed from the X direction.

The guide member 23 is provided so as to extend from the outer peripheral edge of the glass substrate 21 toward the center of the main surface of the glass substrate 21. In the case where the guide member 23 projects in the horizontal direction from the side edge 38 of the glass substrate 21, the projecting length La of the guide member 23 is preferably 20% or more, more preferably 30% or more, preferably 50% or less, more preferably 40% or less of the width W of the glass substrate 21 in the projecting direction thereof.

By setting the extension La to be equal to or greater than the lower limit value, excessive deflection of the glass substrate 21 is suppressed, and the state of supporting the glass substrate 21 can be reliably maintained. Further, by setting the extension La to the upper limit or less, contact between the main surface of the glass substrate 21 and the guide member 23 is suppressed, and the influence of damage or the like due to contact with the glass substrate 21 is less likely to occur.

The guide member 23 is provided at a position having a height Ha in the vertical direction from the lower side 33 of the glass substrate 21 having its main surface standing in the vertical direction. Preferred range R of height Ha_HThe height position is 45% or more, preferably 50% or more, and more preferably 60% or more, with respect to the height H of the glass substrate 21, and is 95% or less, preferably 90% or less, and more preferably 85% or less, with respect to the height H of the glass substrate 21. Here, the height position of n% with respect to the height H means a height position obtained by adding n% of the height H to the lower side 33 of the glass substrate 21.

By disposing the guide member 23 in the above range R of the glass substrate 21_HWhen the glass substrate 21 is bent, the guide member 23 contacts at a position avoiding the center of the glass substrate 21. Therefore, a main portion of the main surface of the glass substrate 21 can be protected. Further, a large contact pressure is not generated at the contact position of the guide member 23 and the bent glass substrate 21, and the glass substrate 21 can be effectively supported.

The guide member 23 shown in fig. 4 is disposed between the second support member 39 and the upper side 34 of the glass substrate 21 in the vertical direction of the glass substrate 21, but may be disposed on the lower side 33 side of the glass substrate 21. That is, the lower guide member 24 is disposed in a range from the lower side 33 of the glass substrate 21 to a height position of 50% with respect to the height H of the glass substrate 21 below the guide member 23. In this case, the guide members are disposed on both the upper side 34 and the lower side 33 of the glass substrate 21, and the bent glass substrate 21 can be supported more stably.

Instead of the guide member 23, the lower guide member 24 may be disposed only on the lower side 33 side of the glass substrate 21. In this case, it is preferable to increase the number of the guide members or to extend the protruding length to sufficiently secure the contact length of the guide members with the glass substrate 21.

(Explanation of action)

Next, the operation of the above-described structure will be described.

Fig. 5 is a plan view of a main part showing a positional relationship between the guide member 23 and the glass substrate 21 at the time of deformation.

The glass support portion 31 locks the side 38 (see fig. 4) of the glass substrate 21 in the support concave portion 41 of the second support member 39 facing thereto. The guide member 23 is provided adjacent to the support recess 41 in which the glass substrate 21 is locked.

When the glass substrate 21 is flat, the guide member 23 is separated from the main surface of the glass substrate 21. When the glass substrate 21 is deflected in the thickness direction (X direction), the guide member 23 comes into contact with the convex main surface of the glass substrate 21 before the locking of the glass substrate 21 with at least one of the first support member 35 and the second support member 39 is released, thereby suppressing the deflection of the glass substrate 21. In this case, the glass substrate 21 is bent into a curved surface shape, and therefore, is in a state of substantially point contact with the guide member 23 made of a wire material. That is, the guide member 2 may be in contact with the glass substrate 21 in a small area.

In this way, the glass substrate 21 is held in an upright posture in a state where its own weight is supported by the first support member 35 and the falling of the glass substrate to either one of the principal surfaces in the thickness direction is restricted by the second support member 39. That is, the glass substrate 21 is stably held by only gravity without applying an external force for supporting the substrate. In this holding state, the glass substrate 21 is not forcibly bent by an external force, and therefore, a stress difference is not generated in the main surfaces of one and the other of the glass substrates 21 by the chemical strengthening treatment, and deformation of the glass substrate 21 after the chemical strengthening treatment is prevented.

In addition, the glass containing portion 29 is provided with a guide member 23. The guide member 23 comes into contact with the convex main surface of the glass substrate 21 when the glass substrate 21 is greatly deflected or pushes back the convex main surface to return to the original flat shape. This suppresses excessive deflection of the glass substrate 21. That is, even if the glass substrate 21 is greatly deflected, the guide member 23 is pressed to maintain the locked state until the locking of the lower side 33 is released from the support recess 41 of the first support member 35 or the locking of the side 38 is released from the support recess 41 of the second support member 39. Therefore, even when the glass substrate 21 is bent, the glass substrate 21 can be reliably prevented from falling off the glass accommodating portion and being damaged (broken). Further, the presence of the guide member 23 prevents the glass substrate 21 from being greatly bent and pushed against surrounding members, thereby preventing damage.

Further, since the guide member 23 is formed by bending a wire, it is less likely to cause a liquid flow obstruction and the liquid treatment of the glass substrate 21 can be performed without collision, for example, as compared with a case where the guide member is formed of a flat plate-like member.

In addition, in this method for processing a glass substrate, even if the glass substrate 21 is thin glass having a thickness of 0.2mm or less, which is likely to cause a shape change (bending or warping), the glass substrate 21 can be stably held. Further, the occurrence of variations in flatness of the plurality of glass substrates 21 supported by the cassette 25 can be suppressed.

The first support member 35 and the second support member 39 have support recesses 41 having a groove width larger than the thickness of the glass substrate 21. If the support concave portion 41 is a V-shaped groove, a pair of corners (edges) where a pair of main surfaces of the glass substrate 21 and an outer peripheral end surface connecting the pair of main surfaces intersect are in contact with a groove inner surface of the V-shaped groove. In this case, the support concave portion 41 does not contact the pair of main surfaces, and damage to the main surfaces due to contact of the support concave portion 41 is prevented.

The guide member 23 projects from the peripheral edge of the glass substrate 21 toward the center of the main surface, and the projecting amount La is set in accordance with the width W in the projecting direction of the glass substrate 21 (the height H in the case of projecting from the upper side 34 or the lower side 33). When the glass substrate 21 is flexed, the amount of deformation (protrusion) of the glass substrate 21 in the thickness direction is greater in the central portion of the main surface than in the peripheral portion, and therefore the flexing of the glass substrate 21 is restricted by the protruding guide member 23. The effect of suppressing deformation by the guide member 23 is maximized by the guide member 23 protruding to the center of the main surface.

The first support member 35 and the second support member 39 are respectively mounted on the cartridge main body 27 along one direction, and a plurality of support recesses 41 are formed in a row along the longitudinal direction thereof. In this way, since the support recesses 41 are formed at the same phase in the longitudinal direction of the first support member 35 and the second support member 39, that is, at the corresponding positions, the plurality of glass substrates 21 can be supported in parallel with each other. Therefore, the cassette main body 27 can support the plurality of glass substrates 21 collectively while being separated from each other.

When the glass substrate 21 is placed in a high-temperature molten salt and the chemical strengthening step is performed, the glass support portion 31 supports the glass substrate 21 without applying an external force to the glass substrate 21. The guide member 23 suppresses flexure of the glass substrate 21 and prevents the glass substrate 21 from falling off the glass support portion 31. As a result, the glass substrate 21 can be held securely while being held in a state in which it stands by its own weight, and the chemical strengthening treatment can be performed in a state in which the glass substrate 21 is stable.

Further, since the first support member 35, the second support member 39, and the guide member 23 are made of stainless steel, deterioration or deformation of the materials is less likely to occur in the chemical strengthening step in which the treatment temperature reaches a high temperature of, for example, 330 to 450 ℃. This prevents the glass substrate 21 from coming off due to the deformation of the first support member 35, the second support member 39, and the guide member 23, and prevents the deflection restricting function from being reduced, and the glass substrate 21 can be supported in a stable state.

Next, a modified example of the first configuration example will be described.

(first and second modifications)

Fig. 6 (a) is a plan view of a main portion of the cartridge showing the arrangement of the guide member 23 of the first modification, and fig. 6 (B) is a plan view of a main portion of the cartridge showing the arrangement of the guide member of the second modification.

As shown in fig. 6 (a), the guide member 23 of the first modification projects only from one side portion of the cartridge main body 27. In this case, the guide member 23 preferably has a projecting length in which the leading end in the projecting direction exceeds the center of the glass substrate 21 in the horizontal direction.

Further, as shown in fig. 6 (B), the guide members 23 of the second modification project alternately in the arrangement direction of the guide members 23 from both sides of the mutually opposing one side and the other side of the cartridge main body 27. In this case, the leading end of the guide member 23 in the extending direction preferably exceeds the center of the glass substrate 21, but may not exceed the center.

(third to sixth modifications)

Fig. 7 (a) is a front view of a cartridge showing the arrangement of guide members of a third modification, fig. 7 (B) is a front view of a cartridge showing the arrangement of guide members of a fourth modification, fig. 7 (C) is a front view of a cartridge showing the arrangement of guide members of a fifth modification, and fig. 7 (D) is a front view of a cartridge showing the arrangement of guide members of a sixth modification.

As shown in fig. 7 (a), the guide member 23 of the third modification is disposed so as to protrude downward from the upper edge portion 27a of the cartridge main body 27 in the front view of the cartridge main body 27 as viewed from the X direction. As shown in fig. 7 (B), the guide member 23 of the fourth modification is disposed obliquely so as to project upward on both sides of one side edge portion 27B and the other side edge portion 27c of the cartridge main body 27, which face each other.

According to the guide member 23 of the second and fourth modified examples, when the glass substrate 21 is flexed and the guide member 23 is in contact with the principal surface of the glass substrate 21, the glass substrate 21 and the guide member 23 are in a point contact state. Thus, the influence of damage or the like to the glass substrate 21 due to contact with the guide member 23 can be minimized.

As shown in fig. 7 (C) and 7 (D), a circular guide member 23A is used in the fifth modification, and a rectangular guide member 23B is used in the sixth modification. By forming the guide members in an annular shape in this manner, the portions of the guide members 23A and 23B that overlap the main surface of the glass substrate 21 in the thickness direction are curved. In this case, since the guide member 23 is in line contact with the glass substrate 21, the contact pressure against the glass substrate 21 can be reduced.

(seventh modification)

Fig. 8 is a perspective view of a cartridge 25A of a seventh modification.

The cassette main body 27 of the cassette 25A is provided with a stopper 43 for preventing the glass substrates 21 from floating upward above the plurality of glass substrates 21. The stopper member 43 is a beam member attached to the upper portion of the cartridge main body 27 and having a longitudinal direction along the X direction. The stopper 43 is fixed to be detachable from the cassette main body 27 so as to be close to or in contact with the upper side 34 of the glass substrate 21. The glass substrate 21 is accommodated in the cassette main body 27 in a state where the stopper member 43 is detached from the cassette main body 27, and after the glass substrate 21 is accommodated, the stopper member 43 is fixed to the cassette main body 27.

When the cassette 25A having the above-described structure is placed in a liquid such as a processing liquid, buoyancy is generated in each glass substrate 21. Even in this case, according to this configuration, the upper edge 34 of the glass substrate 21 to be floated by the buoyancy is brought into contact with the stopper member 43, and further movement is prevented. Thus, the floating of the glass substrate 21 is restricted, and the lower side 33 of the glass substrate 21 can be prevented from coming off the support concave portion 41 of the first support member 35. Therefore, the glass substrate 21 can be stably held even in a liquid. Since the difference in specific gravity between the molten salt and the glass is small, the effect of preventing the glass substrate 21 from floating up by the stopper member 43 is particularly useful in a chemical strengthening process in which the glass substrate is likely to float.

In the first configuration example and the modifications described above, the support concave portion 41 is described as a groove having a V-shaped cross section in the axial direction as shown in fig. 9 (a), but the present invention is not limited thereto. As shown in fig. 9 (B), the support recess 41 may have a rectangular groove 41A in an axial cross section. In this case, the groove width Pc of the groove 41A is larger than the thickness t of the glass substrate 21, and is preferably 1.5 times or more and 3 times or less of the thickness t.

Fig. 10 is a plan view of a main portion showing a dimensional relationship between the pair of second supporting members 39 and the glass substrate 21.

When the support concave portions 41 of the second support member 39 are V-shaped grooves, the groove inner surfaces of the support concave portions 41 support both ends (side edges) in the Y direction of the glass substrate 21. At this time, the state in which the groove inner surface of the support concave 41 is in contact with the pair of edges at both ends of the glass substrate 21 in the Y direction is the minimum distance Lsa between the pair of second support members 39.

However, when a temperature change occurs in each portion such as the cartridge main body, a difference in thermal expansion (contraction) occurs between the glass substrate 21 and the glass substrate having a particularly small linear expansion coefficient. Therefore, the pair of second support members 39 are preferably arranged at an inter-shaft distance Lsb larger than the minimum inter-shaft distance Lsa while changing the position of the axis Oa to the axis Ob. This can prevent stress from being applied to the glass substrate 21 due to thermal expansion of the cartridge main body 27, the second support member 39, and the like.

< second construction example >

The case where the glass substrate is chemically treated has been described above. Next, a case where the chemical liquid treatment is performed on the glass substrate will be described.

The liquid processing step using the cartridge of the second configuration example is a chemical liquid processing step after the chemical strengthening treatment, and includes an acid processing step 15, an alkali processing step 17 after the acid processing step, and a cleaning step 19.

In the chemical solution treatment step, the following specific problems exist.

Since the processing liquid is made to flow, the holding force of the glass substrate by the guide member is required to be higher than that in a still water state. It is also necessary to prevent damage to the main surface of the glass substrate and adhesion of stains.

However, in the chemical solution treatment step, the presence or absence of chemical resistance (acid resistance, alkali resistance) and heat resistance with respect to the first supporting member 47, the second supporting member 49 and the guide member 51 is not a particular problem. Therefore, as the material of the first support member 47, the second support member 49, and the guide member 51, a resin material such as a fluorine-containing resin (PFA (perfluoroalkoxyalkane), PTFE (polytetrafluoroethylene), or the like), PP (polypropylene), PE (polyethylene), or the like can be used. In addition, from the viewpoint of reducing the contact surface pressure, it is preferable to increase the contact length (or the number of contact points, the arrangement density of the contact points) between the glass substrate and the guide member, contrary to the case of the chemical strengthening step.

(Box)

Fig. 11 is a schematic perspective view schematically showing a cassette 45 of a second configuration example used in a chemical liquid processing step of a glass substrate. In fig. 11, the cassette 45 is schematically illustrated for simplifying the explanation of the cassette 45, and the number of accommodated glass substrates 21 and the size of each part are not limited to these but may be any.

The cassette 45 has a glass accommodating portion 29 for holding a plurality of glass substrates at the same time. The glass accommodating portion 29 includes a glass support portion 31 and a guide member 51.

The glass support portion 31 includes a first support member 47 and a second support member 49, wherein the first support member 47 engages the lower edge 33 of the glass substrate 21 in the lower vertical direction, and the second support member 49 engages the side edge 38 of the glass substrate 21 in the upper vertical direction than the lower edge 33.

The first support member 47 and the second support member 49 may be arranged in three or more rows. Further, the first support member 47 may be configured to be disposed only in one row.

As in the first configuration example, the first support member 47 and the second support member 49 are fixed at both ends in the longitudinal direction in a state where the box main body 53 formed in a frame shape or a box shape is bridged from one end to the other end.

The cassette 45 of this configuration is different from the cassette 25 of the chemical strengthening step in that the glass support portion 31 and the guide member 51 provided in the cassette 45 are used in the chemical solution treatment step.

(guide member)

The guide member 51 provided in the cartridge main body 53 of this configuration is formed in a substantially semicircular ring shape in plan view by bending a stainless steel wire rod, and the outer surface of the wire rod is covered with the above-described tube made of a resin material.

Fig. 12 is a cross-sectional view of the guide member 51 of the second configuration example in the direction orthogonal to the axis.

The guide member 51 is formed by covering the surface of a core 55 as a wire material with a resin material 57 such as a fluorine resin.

The first support member 47 and the second support member 49 as the glass support portion 31 shown in fig. 11 are formed of the resin material such as the fluorine-containing resin described above.

Fig. 13 is a schematic plan view of the cartridge 45 according to the second configuration example. In fig. 13, the first supporting member 47 on the lower side of the cartridge 45 is omitted.

The second support member 49 has a plurality of support recesses 41 formed with a groove width Pb. The second support member 49 is provided with a plurality of guide members 51. The guide members 51 are preferably provided at a constant arrangement interval Pd along the thickness direction (X direction) of the glass substrate 21. The arrangement interval Pd of the guide member 51 is shorter than the arrangement interval Pa (see fig. 3) of the guide member 23 of the first configuration example. That is, the guide member 51 is disposed in the vicinity of the glass substrate 21 as compared with the case of the first configuration example.

The arrangement interval Pd of the guide members 51 is preferably 5000 times or less, more preferably 4000 times or less, and still more preferably 2500 times or less the thickness t of the glass substrate 21. The distance Pd is preferably equal to or greater than the groove width Pb of the support recess 41.

Fig. 14 is a schematic front view of the cartridge 45 of the second configuration example viewed from the X direction.

The guide member 51 is disposed in an imaginary plane parallel to the principal surface of the glass substrate 21. The guide member 51 has a D-shape in plan view, and the D-shape has an upper linear portion 51a and curved portions 51b projecting downward from both ends of the linear portion 51 a. The guide member 51 is supported by the second support member 49 at the connecting position of the curved portion 51b and both ends of the linear portion 51 a.

Even when the glass substrate 21 is subjected to an external force due to a flow of liquid, such as a chemical treatment step including an acid treatment step, an alkali treatment step, a cleaning step, and the like, the guide member 51 needs to reliably hold the glass substrate on which the deflection is generated. Therefore, the guide member 51 is preferably in contact with the main surface of the glass substrate 21 over a wide range.

Thus, the shape of the guide member 51 is set as follows.

The guide member 51 is projected from the thickness direction (X direction) of the glass substrate 21 supported by the first support member 47 and the second support member 49 toward the main surface of the glass substrate 21. Fig. 15 is an explanatory diagram schematically showing a two-dimensional projection image 61 in which a region where the guide member 51 overlaps the main surface of the glass substrate 21 is indicated by a hatching S.

The shadow S of the projection image 61 is projected (Pj _ Y) onto the vertical side 63 of the glass substrate 21 in the horizontal direction (Y direction) of the glass substrate 21 to obtain a one-dimensional shadow vertical distribution. In fig. 15, the result of projecting the shadow S is shown as a shadow existence region 65. The total width Gh of the shadow existence regions 65 in the shadow vertical distribution may be preferably 50% or more, more preferably 60% or more, and still more preferably 70% or more of the width H in the vertical direction of the glass substrate 11.

Similarly, the shadow S of the projection image 61 is projected (Pj _ Z) onto the horizontal side 67 of the glass substrate 21 in the vertical direction (Z direction) of the glass substrate 21 to obtain a one-dimensional shadow horizontal distribution. The total width Gw of the shadow existence regions 69 in the shadow horizontal distribution may be preferably 50% or more, more preferably 60% or more, and still more preferably 70% or more of the width W of the glass substrate 21 in the horizontal direction.

Although not shown, when the guide member 51 is provided at a plurality of positions facing the main surface of the glass substrate 21, the above-described shadows S are dispersed at a plurality of positions of the projection image 61. In the above case, the total width of the plurality of or single shadow existence regions 65 overlapping each other, which are obtained by projecting the plurality of shadows S in the horizontal direction, is set to the total width Gh of the shadow existence regions. Similarly, the total width of a plurality of or single overlapping shadow existence regions 69 obtained by projecting the plurality of shadows S in the vertical direction is made equal to the total width Gw of the shadow existence regions.

Preferably, the shadow existence region 65 in the vertical distribution of the shadows and the shadow existence region 69 in the horizontal distribution of the shadows include the center of gravity of the glass substrate 21, i.e., the center O of the main surface. In this case, since the guide member 51 is in contact with the region including the center O of the main surface of the glass substrate 21, the glass substrate 21 is supported by the guide member 51 in a more stable manner.

The shape of the guide member 51 is not limited to the D-shape, but it is preferable to increase the contact length with the glass substrate 21 and the number of contact points within a range that does not obstruct the flow of the processing liquid when the glass substrate 21 is bent. This can stably support the bent glass substrate 21 while suppressing the contact pressure to a small level.

(Explanation of action)

Next, the operation of the above-described structure will be described.

In this glass substrate processing method, in the chemical processing step of disposing the glass substrate 21 in a liquid flow, the cassette 45 holds the glass substrate 21 by the glass support portion 31 and the guide member 51. Further, the holding capability of the glass substrate 21 is further improved by increasing the contact length and the number of contact points of the guide member 51 with the glass substrate 21. Thus, even if an external force due to the flow of liquid acts on the glass substrate 21 during the liquid treatment, the cassette 45 continues to hold the glass substrate 21 in the standing state without damaging the glass substrate. As a result, the glass substrate 21 can be processed in a stable state.

The first support member 47, the second support member 49, and the guide member 51 are covered with a resin material 57 such as a fluorine-containing resin. Therefore, even if the glass substrate 21 comes into contact with the first support member 47, the second support member 49, and the guide member 51 in the chemical liquid processing step in which the liquid flows, the glass substrate 21 is not damaged. Further, when the resin material 57 is a fluorine-containing resin, stains are less likely to adhere, and adhesion of stains to the glass substrate 21 can be suppressed.

The arrangement interval Pd of the guide member 51 is set to an interval within the above-described range shorter than the arrangement interval Pa (see fig. 3) of the guide member in the chemical strengthening step. Therefore, the deflection generated in the glass substrate 21 by the liquid flow is suppressed to be small.

The stopper 43 shown in fig. 8 described above is preferably provided in the cartridge main body 53 of the cartridge 45. This more reliably suppresses floating of the glass substrate 21.

< other application example >

The method of processing a glass substrate is applied to the chemical strengthening step 11, the acid treatment step 15, the alkali treatment step 17, and the cleaning step 19 as the chemical treatment step shown in fig. 1, but may be applied to the cleaning step 13 after the chemical strengthening step 11. The cartridge in the above case has the same configuration as the chemical strengthening step of the first configuration example in the cleaning step 13 in which the liquid is not stirred.

Therefore, according to this glass substrate processing method, by using cassettes having appropriate configurations according to different constraints depending on the contents of liquid processing, it is possible to appropriately support the glass substrate in each liquid processing. As a result, various processing steps can be performed while maintaining the glass sheet in a stable state on the sheet surface without affecting the quality of the glass. Therefore, the glass substrate 21 having a high yield and suppressed deformation of the processed glass can be stably manufactured.

As described above, the present invention is not limited to the above-described embodiments, and combinations of the respective configurations of the embodiments or modifications and applications thereof by those skilled in the art based on the description of the specification and well-known techniques are intended to be included in the scope of the present invention.

The above-described embodiment illustrates the structure for supporting the thin plate glass, but is not limited thereto. According to the method for processing a glass substrate of the present invention, a large-sized glass plate having a thickness sufficiently small with respect to the area of the main surface can be stably supported in the same manner. For example, in a large glass plate having one side of, for example, more than 1000mm used for a large liquid crystal display, a window of a building, or the like, the glass plate is easily deformed from a flat state by gravity. When such a glass plate is subjected to liquid treatment, it can be stably held as in the case of a thin glass plate.

< chemically strengthened glass substrate >

The chemically strengthened glass substrate subjected to the chemical strengthening treatment using the above jig is suppressed in cracks and warpage. That is, the chemically strengthened glass substrate of the present invention has a pair of main surfaces facing each other, and is characterized in that the ratio a/t of the area a of the main surfaces to the thickness t between the pair of main surfaces is 25000 or more, and the difference between the value of the compressive stress of one main surface and the value of the compressive stress of the other main surface of the pair of main surfaces is 10MPa or less.

The ratio a/t of the area a of the main surface to the thickness t between the pair of main surfaces is preferably 100000 or more, more preferably 125000 or more, and further preferably 180000 or more. The thickness t between the pair of main surfaces is preferably 0.2mm or less.

When the difference between the compressive stress value of one of the pair of main surfaces and the compressive stress value of the other main surface is preferably 8MPa or less, more preferably 6MPa or less, further preferably 4MPa or less, and further preferably 2MPa or less, warpage of the glass substrate can be suppressed.

In this case, sufficient strength can be obtained when the compressive stress of each of the pair of principal surfaces of the chemically strengthened glass substrate is preferably 600MPa or more, more preferably 700MPa or more, and still more preferably 800MPa or more.

Further, when the difference between the depth of the compressive stress layer in one of the pair of main surfaces and the depth of the compressive stress layer in the other main surface is preferably 0.1 μm or less, more preferably 0.07 μm or less, and even more preferably 0.05 μm or less, warpage can be suppressed.

In this case, the depth of the compressive stress layer in each of the pair of principal surfaces of the chemically strengthened glass substrate is preferably 3 μm or more, and more preferably 5 μm or more. On the other hand, the depth of the compressive stress layer is preferably 30 μm or less.

[ examples ] A method for producing a compound

Here, glass substrates (experimental examples 1 to 4) in which the chemical strengthening treatment step was performed using the cassette shown in fig. 2 and then the chemical liquid treatment step was performed using the cassette shown in fig. 11 were compared with glass substrates (experimental examples 5 to 7) in which the chemical strengthening treatment step and the chemical liquid treatment step were performed using a cassette in which the glass substrates were bent and deformed and supported. Table 1 shows the processing conditions and the processing results for each glass substrate. The glass substrate used had a thickness of 0.13mm in experimental example 1 and experimental example 5, a thickness of 0.10mm in experimental example 2 and experimental example 6, a thickness of 0.07mm in experimental example 3 and experimental example 7, and a thickness of 0.05mm in experimental example 4. In addition, as a base material of each glass substrate, special glass for chemical strengthening (registered trademark: dragonttail Pro) was used.

[ TABLE 1 ]

Table 2 and table 3 show the dimensions of the guide member and the second support member used in the chemical strengthening treatment step and the guide member used in the chemical treatment step. The guide member and the second support member of type 1 were used in the chemical strengthening treatment steps of experimental examples 1 to 4.

[ TABLE 2 ]

TABLE 2 procedure of chemical strengthening treatment

	Type 1	Type 2	Type 3
				Extension Da of guide member	31	50	90
Groove depth Db of support recess of second support member	6	6	6
				Arrangement interval Pa of guide member	26	30	30
Groove width Pb of support recess of second support member	6	6	6
				Extension La of guide member toward glass substrate	25	44	84
Height Ha of guide member from lower edge of glass substrate	120	120	120

Unit: mm is

[ TABLE 3 ]

TABLE 3 liquid medicine treatment Process

Total width Gw in horizontal direction	155
		Total width Gh in vertical direction	145

Unit: mm is

The chemical strengthening treatment steps of experimental examples 1 to 4 were performed in a state in which the glass substrate was held flat without being bent, and the chemical strengthening treatment steps of experimental examples 5 to 7 were performed in a state in which the glass substrate was held bent by applying an external force thereto in the same manner as in the conventional art.

As a result, in experimental examples 5 to 7, the value (compressive stress difference ratio Δ CS) obtained by dividing the difference in the compressive stress value CS between the pair of principal surfaces (first surface and second surface) of the glass substrate by the first surface compressive stress value was 1.1 to 2.4%, and the value (compressive stress layer depth ratio Δ DOL) obtained by dividing the difference in the depth DOL of the compressive stress layer by the depth of the first surface compressive stress layer was 1.6 to 3.9%. The yield of the undamaged glass substrate (undamaged yield) was 79 to 95%, and distortion was observed in the glass substrate.

In contrast, in examples 1 to 4, the difference in compressive stress Δ CS is 0.2 to 0.6% and smaller than those in examples 5 to 7, and the depth of layer ratio of compressive stress Δ DOL is 0.1 to 1.1% and smaller than those in examples 5 to 7. In addition, the breakage-free yield was 99% or more and the lowest yield was 96% in experimental examples 1, 2 and 4, and deformation of the glass substrate was hardly observed. These results are considered to be because the glass substrate was not bent.

As described above, the values of experimental examples 1 to 4 as examples are smaller than those of experimental examples 5 to 7 as comparative examples with respect to the compressive stress difference ratio Δ CS and the depth ratio Δ DOL of the compressive stress layer, and it can be said that chemical strengthening treatment can be achieved in experimental examples 1 to 4 more stably than in experimental examples 5 to 7. Regarding the degree of deformation, the case where almost no deformation was observed on the entire glass substrate was evaluated as "o", the case where deformation was observed in some portions was evaluated as "Δ", and the case where large deformation that was an obstacle in actual use was observed was evaluated as "x".

In addition, in the case where the guide members of type 2 and type 3 were used in the chemical strengthening treatment step, as in the case where the guide member of type 1 was used, the results of the compressive stress difference ratio, the compressive stress depth of layer ratio, the yield without breakage, and the degree of deformation of the substrate were all good as compared with the experimental examples 5 to 7.

As described above, the following matters are disclosed in the present specification.

(1) A method for processing a glass substrate, comprising the steps of:

preparing a glass substrate having a pair of main surfaces facing each other, wherein a ratio A/t between an area A of the main surfaces and a thickness t between the pair of main surfaces is 25000 or more;

holding the glass substrate in a glass accommodating portion in an orientation in which the main surface is substantially parallel to the vertical direction; and

performing liquid treatment on the glass substrate while keeping the glass substrate in the glass accommodating portion,

the glass storage unit includes:

a glass support portion for supporting the glass substrate by a first support member for locking a lower side peripheral edge portion of the glass substrate below in a vertical direction and a second support member for locking an upper side peripheral edge portion of the glass substrate above in the vertical direction; and

guide members provided on one side and the other side in the thickness direction of the glass substrate supported by the glass support portion,

when the glass substrate is flat, the guide member is separated from the main surface of the glass substrate,

when the glass substrate is deflected, the guide member contacts the main surface on the convex side of the glass substrate before the engagement between the glass substrate and at least one of the first support member and the second support member is released, thereby suppressing the deflection of the glass substrate.

According to the glass substrate processing method, the glass substrate is supported by the first support member with its own weight, and is held in an upright posture by the second support member while being restricted from falling to any one of the main surfaces. That is, the glass substrate is held by its own weight without applying an external force. The glass storage unit is provided with a guide member. The guide member contacts the convex main surface of the glass substrate before the glass substrate is released from locking with at least one of the first support member and the second support member, thereby suppressing the glass substrate from being bent. The glass substrate supported by the guide member with the deflection thereof suppressed can be reliably prevented from being damaged (cracked) by falling off from the glass accommodating portion. Further, since the glass surface is not greatly bent and pushed against surrounding members, the glass substrate is less likely to be damaged.

(2) The method for processing a glass substrate according to (1), wherein the glass substrate has a thickness of 0.2mm or less.

According to this method for processing a glass substrate, even thin glass having a thickness of 0.2mm or less can be stably held in the glass accommodating portion by the glass support portion and the guide member.

(3) The method for processing a glass substrate according to the above (1) or (2), wherein the guide member is formed by bending a wire.

According to this glass substrate processing method, since the guide member is formed of a wire, the liquid flow is less likely to be obstructed, and the liquid processing of the glass substrate can be performed without collision.

(4) The method for treating a glass substrate according to any one of (1) to (3). The first support member and the second support member are formed with support recesses having a larger groove width than the thickness of the glass substrate, and the peripheral edge portions of the glass substrate are inserted into the support recesses to support the glass substrate.

According to the method for processing a glass substrate, the glass substrate is stably supported with the peripheral edge portion of the glass substrate inserted into the support recess. Further, the glass substrate can be arbitrarily positioned by the support concave portions of the first support member and the second support member, and the support posture can be set.

(5) The method for processing a glass substrate according to (4), wherein the guide member extends from a peripheral edge portion of the glass substrate toward a center of the main surface so as to be longer than a groove depth of the support recess.

According to this glass substrate processing method, when the glass substrate is deflected, the protruding guide member is brought into contact with the central portion of the convex main surface of the glass substrate, whereby the deflection of the glass substrate can be stably restricted.

(6) The method for processing a glass substrate according to (4) or (5), wherein the first support member and the second support member have a plurality of support recesses formed in a longitudinal direction thereof,

the glass container includes a box body formed in a frame shape or a box shape, and the first support member and the second support member are respectively provided so as to extend in one direction,

the plurality of glass substrates are held in the support concave portions of the first support member and the support concave portions of the second support member so as to be separated from each other.

According to this glass substrate processing method, since a plurality of support concave portions of the first support member and the second support member are formed in the longitudinal direction of the first support member and the second support member, the plurality of glass substrates can be supported in parallel. That is, the cassette main body can support a plurality of glass substrates collectively while separating them from each other.

(7) The method for processing a glass substrate according to item (6), wherein a stopper member for preventing the glass substrate from floating up is provided above the plurality of glass substrates in the cassette main body.

According to this method for processing a glass substrate, even if the cassette main body is disposed in a liquid and buoyancy is generated in each glass substrate, the floating of the glass member can be restricted by the upper peripheral edge portion of the glass substrate coming into contact with the stopper member provided above the cassette main body. This enables stable holding of the glass substrate even in a liquid.

(8) The method of processing a glass substrate according to any one of (4) to (7), wherein a groove width of the support recess in a thickness direction of the glass substrate is 1.5 times or more and 3 times or less a thickness of the glass substrate.

According to this method for processing a glass substrate, a suitable gap can be secured between the groove inner surface of the support recess and the glass substrate, and the glass substrate can be stably supported.

(9) The method of processing a glass substrate according to any one of (4) to (8), wherein the glass substrate is disposed at a distance in a thickness direction of the glass substrate within a range of 0.00006 to 0.0006 times a value A/t obtained by dividing an area A of a main surface of the glass substrate by a thickness t between a pair of main surfaces.

According to this method for processing a glass substrate, the arrangement interval of the glass substrates can be set to an appropriate length according to the thickness of the glass substrate and the area of the main surface, and the glass substrate can be stably supported.

(10) The method for processing a glass substrate according to any one of (4) to (9), wherein an arrangement interval at which the guide members are arranged in a thickness direction of the glass substrate is larger than a groove width of the support recess and is 5000 times or less as large as a thickness of the glass substrate.

According to the method of processing a glass substrate, the glass substrate can be supported between the adjacent guide members by disposing the guide members at a larger interval than the disposition interval of the support recesses.

(11) The method for processing a glass substrate according to any one of (4) to (10), wherein a position at which the guide member is disposed in the vertical direction is within a range from a lower edge of the glass substrate to a height of 45% or more of a width of the glass substrate in the vertical direction and to a height of 95% or less of the width of the glass substrate in the vertical direction.

According to this method for processing a glass substrate, since the guide member is disposed above the glass substrate in the vertical direction, the deflection of the glass substrate can be effectively restricted, and the contact surface pressure against the glass substrate can be reduced.

(12) The method of processing a glass substrate according to any one of (4) to (11), wherein an amount of protrusion of the guide member from one side edge of the glass substrate toward the other side edge is 20% or more of a width of the glass substrate in a horizontal direction.

According to this method for processing a glass substrate, since the guide member is disposed above the glass substrate in the vertical direction, the deflection of the glass substrate can be effectively restricted, and the contact surface pressure against the glass substrate can be reduced.

(13) The method for processing a glass substrate according to (11) or (12), wherein a pair of the guide members are provided so as to extend from one side edge and the other side edge of the glass substrate toward a center of a main surface of the glass substrate.

According to this glass substrate processing method, since the guide members are disposed so as to protrude from both the one side edge and the other side edge of the glass substrate, the bent glass substrate can be supported in a balanced manner.

(14) The method for treating a glass substrate according to any one of (1) to (13), wherein the step of performing the liquid treatment is a step of performing a chemical strengthening treatment on the glass substrate.

According to this method for processing a glass substrate, in the chemical strengthening treatment in which a glass substrate is placed in a high-temperature molten salt, the glass substrate can be held in a state in which the glass substrate is raised by its own weight by the glass support portion and the guide member. In this holding state, since the glass substrate is not forcibly deformed by an external force, a stress difference is not generated on the front and back surfaces of the glass substrate by the chemical strengthening treatment, and the deformation of the glass substrate after the chemical strengthening treatment is suppressed.

(15) The method for processing a glass substrate according to (14), wherein the first support member, the second support member, and the guide member are made of a stainless material.

According to this method for processing a glass substrate, even if the glass substrate is exposed to a high processing temperature of about 400 ℃ by chemical strengthening treatment, thermal deformation and deterioration of the first support member, the second support member, and the guide member can be prevented. Further, since the rigidity is high, the glass substrate can be stably supported.

(16) The method for processing a glass substrate according to (14) or (15), wherein a lower guide member disposed below the guide member is further provided within a range of a height from a lower edge of the glass substrate that is less than 45% of a width of the glass substrate in a vertical direction.

According to this glass substrate processing method, when the glass substrate is flexed, the upper side and the lower side of the glass substrate are brought into contact with the guide member together, whereby the glass substrate can be supported more stably.

(17) The method for processing a glass substrate according to any one of (1) to (13), wherein the step of performing the liquid treatment is a chemical liquid treatment step involving a flow of the liquid performed after the chemical strengthening treatment and a cleaning step performed in the chemical liquid treatment step.

According to this glass substrate processing method, even if an external force generated by the liquid flow acts on the glass substrate in the chemical liquid processing step of disposing the glass substrate in the liquid flow and the cleaning step at this time, the glass substrate can be reliably held by the glass support portion and the guide member.

(18) The method for processing a glass substrate according to (17), wherein at least surfaces of the first support member, the second support member, and the guide member are made of a resin material.

According to this method for processing a glass substrate, the glass substrate is in contact with the first support member, the second support member, and the guide member via the resin material, and therefore damage to the glass substrate can be prevented.

(19) The method for processing a glass substrate according to (18), wherein the resin material is a fluorine-containing resin.

According to this method for processing a glass substrate, since the first support member, the second support member, and the guide member are covered with the fluorine-containing resin, stains and foreign matter are less likely to adhere thereto, and stains and foreign matter are less likely to be transferred onto the glass substrate.

(20) The method for processing a glass substrate according to any one of (17) to (19), wherein in a two-dimensional projection image in which the guide member is projected onto the main surface of the glass substrate from the thickness direction of the glass substrate supported by the glass support unit and the region where the guide member overlaps the main surface of the glass substrate is indicated by hatching,

the total width of shadow existing regions in a one-dimensional vertical distribution of shadows formed by projecting the shadows of the projected image onto the vertical side of the glass substrate in the horizontal direction of the glass substrate is 50% or more of the width of the glass substrate in the vertical direction,

the total width of shadow existing regions in a one-dimensional shadow horizontal distribution formed by projecting the shadow of the projected image to the horizontal side of the glass substrate in the vertical direction of the glass substrate is 50% or more of the width of the glass substrate in the horizontal direction.

According to this glass substrate processing method, since the region where the guide member overlaps the main surface of the glass substrate is 50% or more of the width of the glass substrate in the vertical direction and the width of the glass substrate in the horizontal direction, the region of half or more of the main surface is in contact with the guide member, and therefore the glass substrate can be supported more stably. Further, by increasing the contact area, damage to the glass substrate can be suppressed. Therefore, unlike the chemical strengthening treatment in a state close to a still water state, in the chemical treatment step and the cleaning step in which the glass substrate is subjected to an external force by a liquid flow, the contact between the glass substrate and the guide member is increased, and the glass substrate in which the deflection is generated can be reliably held without being damaged.

(21) The method for processing a glass substrate according to item (20), wherein the shadow existence region in the shadow vertical distribution and the shadow horizontal distribution includes a center of a main surface of the glass substrate.

According to the method of processing a glass substrate, the glass substrate is supported by the guide member in a more stable state by bringing the guide member into contact with the region including the center of the main surface of the glass substrate.

(22) A chemically strengthened glass substrate is provided,

has a pair of main surfaces facing each other,

the ratio A/t of the area A of the main surface to the thickness t between the pair of main surfaces is 25000 or more,

the difference between the value of the compressive stress on one of the pair of main surfaces and the value of the compressive stress on the other main surface is 10MPa or less.

According to the chemically strengthened glass substrate, a chemically strengthened glass substrate in which cracks and warpage are suppressed can be obtained.

(23) The chemically strengthened glass substrate according to (22), wherein a ratio A/t of an area A of the main surface to a thickness t between the pair of main surfaces is 100000 or more.

According to the chemically strengthened glass substrate, a chemically strengthened glass substrate in which cracks and warpage are suppressed can be obtained.

(24) The chemically strengthened glass substrate according to the item (22) or (23), wherein a difference between a depth of the compressive stress layer on one of the pair of principal surfaces and a depth of the compressive stress layer on the other principal surface is 0.1 μm or less.

According to the chemically strengthened glass substrate, a chemically strengthened glass substrate in which cracks and warpage are suppressed can be obtained.

(25) The chemically strengthened glass substrate according to any one of (22) to (24), wherein the thickness t between the pair of main surfaces is 0.2mm or less.

According to the chemically strengthened glass substrate, a chemically strengthened glass substrate in which cracks and warpage are suppressed can be obtained.

(26) The chemically strengthened glass substrate according to any one of (22) to (25), wherein the compressive stress values of the pair of main surfaces are 600MPa or more, respectively, and the depths of the compressive stress layers of the pair of main surfaces are 3 μm or more and 30 μm or less, respectively.

According to the chemically strengthened glass substrate, a chemically strengthened glass substrate having sufficient strength can be obtained while suppressing cracking and warping.

The application is based on the Japanese patent application 2019-157195 filed on 8/29 of 2019, the content of which is incorporated herein by reference.