TW201815704A - Method for manufacturing chemically strengthened glass plate and glass plate housing for chemical strengthening - Google Patents

Abstract

In the present invention, a glass plate (G) is chemically strengthened by holding a first side edge (G1) of the glass plate (G), suspending the glass plate (G) with the held first side edge (G1) placed upward, and dipping the glass plate (G) into molten salt while suspending the glass plate (G) for a salt bath treatment. This allows glass plates to be chemically strengthened at high yield and with high quality, and significantly improves the productivity of chemically strengthened glass plates.

Description

Manufacturing method of chemically strengthened glass plate and glass plate containing body for chemical strengthening

The present invention relates to a method for manufacturing a chemically strengthened glass plate and a glass plate container for chemically strengthening the same.

In recent years, display devices such as mobile phones, smart phones, portable information terminals (PDAs), and tablet PCs (personal computers) have become popular. A chemically strengthened glass plate is installed on the surface of the display device as a cover glass to protect the liquid crystal display (LCD). The chemically strengthened glass plate is produced by immersing a glass plate containing Na ions in a molten salt containing K ions and the like. In actual manufacturing, previously, a supporting device that can place a plurality of glass plates at intervals and used the glass plates to be immersed in molten salt has been used. As a document describing a supporting device that can be used for manufacturing a chemically strengthened glass plate, the following Patent Document 1 is proposed. Patent Document 1 shows a supporting device used for heat-treating a glass plate. The supporting device has a structure in which the lower end edge of the glass plate is inserted into the groove of the separation comb for support, and the upper end edge of the glass plate is supported by the separation comb or the separation rod. Prior Art Literature Patent Literature Patent Literature 1: Japanese Patent Publication No. 2010-526753

[Problems to be Solved by the Invention] Of course, the salt bath treatment in the chemical strengthening treatment is carried out by immersing a glass plate at a temperature below the glass transition point (for example, 400 ° C to 530 ° C) to perform ion exchange on the glass plate. A compressive stress layer is formed on the surface, so that a tensile stress layer is formed inside the glass plate. At this time, when the lower edge of the glass plate is inserted into the groove for support as in the supporting device described in the aforementioned Patent Document 1, creep occurs at low temperature on the glass plate due to the weight of the glass plate during the salt bath treatment. Deformation caused by bending or strain is unavoidable. Especially in large and thin glass plates, the deformation due to low-temperature creep appears significantly, so there is a problem that the quality and yield are lowered, and the production efficiency is lowered. The present invention has been made in view of the above circumstances, and an object thereof is to provide a method for producing a chemically strengthened glass sheet and a chemically strengthened glass sheet that can chemically strengthen the glass sheet with high quality and high yield, thereby greatly improving the productivity of the chemically strengthened glass sheet. The body was housed in a glass plate. [Technical means to solve the problem] In order to achieve the above-mentioned object, the method for manufacturing a chemically strengthened glass plate of the present invention is characterized in that the first side edge of the glass plate is grasped, and the first side edge grasped is suspended vertically as an upper part. The glass plate is chemically strengthened by hanging the glass plate and immersing the glass plate in a molten salt while hanging the glass plate. According to the method for manufacturing a chemically strengthened glass plate, while the glass plate is suspended and immersed in molten salt to perform a salt bath treatment, it is possible to suppress the load on the glass plate due to its own weight during the salt bath treatment. Therefore, for example, compared with a case where the glass plate is subjected to a salt bath treatment by being placed vertically, it is possible to suppress deformation caused by low-temperature creep caused by applying a load such as a weight to the glass plate during the salt bath treatment. Thereby, large-scale and thin glass plates can be chemically strengthened with high quality and high yield, and the productivity of chemically strengthened glass plates can be greatly improved. In addition, the chemical-strengthened glass plate container of the present invention is used in the method for manufacturing the chemically-strengthened glass plate, and is put into the molten salt in a state where a plurality of the glass plates are housed, and It is provided with: a frame body which houses a plurality of said glass plates; and a first jig which is arranged on the upper part of the frame body and grasps said first side edge of each said glass plate and hangs out the gap between the glass plates and hangs down Hang the glass plate. According to the chemically strengthened glass plate container of this configuration, by putting the glass plate into the molten salt with the first jig holding the first side edge of the glass plate and hanging it, it is possible to suppress the cause as much as possible. The load caused by the self-weight is given to a plurality of glass plates for salt bath treatment. This makes it possible to chemically strengthen large and thin glass plates while suppressing deformation caused by low-temperature creep. The so-called side edge is the area that holds the glass plate. The side edge is preferably within 30 mm from the outer peripheral end of the glass plate, more preferably within 20 mm from the outer peripheral end, and further preferably within 15 mm from the outer peripheral end, and even more preferably from the outer peripheral end. Within 10 mm. In the glass-plate-accommodating body for chemical strengthening of the present invention, a second jig may be provided at the lower part of the frame, and the second jig may hold each of the glass plates suspended from the first side. The edge is opposite to the second side edge. According to the glass plate storage body for chemical strengthening according to this structure, the second side edge of the lower side of the glass plate suspended by the upper first fixture can be held by the second fixture of the lower portion, which can prevent the The suspended glass plates are in contact with each other due to shaking. This makes it possible to perform chemical strengthening by performing a salt bath treatment without causing damage due to contact between adjacent glass plates. The second jig holding the other side edge of the lower side of the suspended glass plate, that is, the second side edge, as long as it can prevent the glass plates from contacting each other due to shaking, as long as it can suppress the glass plate from shaking Hold it. That is, the holding force of the second jig may be smaller than the holding force of the first jig. In the glass-plate-accommodating body for chemical strengthening of the present invention, the first jigs may be spaced from each other and a plurality of the first jigs may be provided along the first side edge of the glass plate. According to the chemically strengthened glass plate container of this configuration, the first side edge of the glass plate is grasped by using a plurality of first jigs, which can be imparted to the first side as compared with grasping by a single first jig. The external force of the jig is distributed to the plurality of first jigs, so that the influence of the external force imparted on the glass plate due to the grasping by the first jig can be suppressed as much as possible. In the glass plate housing for chemical strengthening of the present invention, the first jig may be supported by the frame through a flexible supporting member. According to the chemically strengthened glass plate storage body having the above configuration, the first jig is supported by the frame body by a flexible supporting member, so that the first jig is softly displaced following the shaking of the glass plate or the like. Thereby, it is possible to suppress as much as possible the application of an external force to the glass plate by the portion held by the first jig. In the glass-plate-accommodating body for chemical strengthening of the present invention, the first jig may include: a pair of clamping plates that hold and hold the glass plate; and buffer materials that are respectively disposed on the The clamping plate faces the glass plate. According to the glass plate storage body for chemical strengthening with this structure, the holding plate that holds and holds the glass plate in the first jig is provided with a buffer material, and therefore, the glass plate is not easily damaged when the glass plate is held. In particular, if a glass cloth having the same properties as a glass plate is used as a buffer material, since the thermal expansion coefficients of the glass plate and the buffer material are approximately the same, damage due to temperature fluctuations during the chemical strengthening step can be suppressed as much as possible. In addition, as a buffer material other than glass cloth, silicon oxide cloth, ceramic cloth, quartz glass, glass plate, and printing cloth can be used. In the glass-plate-accommodating body for chemical strengthening of the present invention, the second jigs may be spaced apart from each other and a plurality of the second jigs may be provided along the second side edge of the glass plate. According to the chemically strengthened glass plate container according to this constitution, the second side edge of the glass plate is held by a plurality of second jigs, and the second plate can be provided to a second side as compared with a single second jig. The external force of the jig is distributed to the plurality of second jigs, so that the influence of the external force imparted on the glass plate due to the grasping by the second jig can be suppressed as much as possible. In the glass plate housing for chemical strengthening of the present invention, the second jig may be supported by the frame through a flexible supporting member. According to the chemically strengthened glass plate storage body of this structure, the second jig is supported by the frame body by a flexible supporting member, so the second jig is softly displaced following the shaking of the glass plate or the like. Thereby, it is possible to suppress the application of external force to the glass plate by the portion held by the second jig as much as possible. In the glass-plate-accommodating body for chemical strengthening of the present invention, the second jig may include: a pair of holding plates that hold and hold the glass plate; and buffer materials that are respectively disposed on the The clamping plate faces the glass plate. According to the chemically strengthened glass plate storage body of this structure, the holding plate that holds and holds the glass plate in the second jig is provided with a cushioning material, so that the glass plate is not easily damaged when the glass plate is held. In particular, if a glass cloth having the same properties as a glass plate is used as a buffer material, since the thermal expansion coefficients of the glass plate and the buffer material are approximately the same, damage due to temperature fluctuations during the chemical strengthening step can be suppressed as much as possible. In addition, as a buffer material other than glass cloth, silicon oxide cloth, ceramic cloth, quartz glass, glass plate, and printing cloth can be used. [Effects of the Invention] According to the present invention, it is possible to provide a method for manufacturing a chemically strengthened glass plate capable of chemically strengthening a glass plate with high quality and a high yield, and greatly improving the productivity of the chemically strengthened glass plate, and a glass plate for chemical strengthening Receiver.

Hereinafter, an embodiment of a method for manufacturing a chemically strengthened glass plate and a glass plate housing for chemical strengthening according to the present invention will be described with reference to the drawings. First, a glass plate housing for chemical strengthening used in a method for manufacturing a chemically strengthened glass plate will be described. FIG. 1 is a schematic perspective view of a glass-plate-accommodating body for chemical strengthening of this embodiment used in the method for manufacturing a chemically-strengthened glass plate of the present invention. As shown in FIG. 1, a glass plate receiving body (hereinafter referred to as a glass plate receiving body) 1 for chemical strengthening in this embodiment is provided with a box-shaped frame 11 having a rectangular parallelepiped shape, and a plurality of frames are housed inside the frame 11. Sheet glass plate G. The frame 11 includes a rectangular upper frame 12 and a rectangular lower frame 14. The upper frame 12 and the lower frame 14 are connected to each other by four side frame members 16 arranged on four sides of the upper frame 12 and the lower frame 14. Further, inside the frame body 11 of the glass plate receiving body 1, a plurality of glass plates G are formed such that the long side direction becomes the left-right direction (arrow A in the figure) and the short side direction becomes the vertical direction (arrow B in the figure). Arranged in the front-rear direction (arrow C in the figure) and housed. The shape of the glass plates G arranged and stored in the glass plate container 1 is not particularly limited. It may be a rectangular glass plate G, and the corners of the glass plate G may be a circular arc shape, or a polygonal shape such as a triangular shape, an oval shape, or a circular shape. The upper frame 12 includes two frame materials 12a constituting a long side and two frame materials 12b constituting a short side. Similarly, the lower frame 14 includes two frame materials 14a constituting a long side and two frame materials 14b constituting a short side. . The frame materials 12 a and 12 b of the upper frame 12, the frame materials 14 a and 14 b of the lower frame 14, and the side frame materials 16 are made of, for example, a U-shaped channel steel made of SUS304 or a hollow square tube. Further, a porous metal mesh 14c made of SUS304 is mounted on the entire surface surrounded by the frame materials 14a and 14b of the lower frame 14. Even if a plurality of glass plates G are housed inside the glass plate housing 1, the glass plate G is sufficiently resistant. Transported and impregnated in molten salt. Further, a hanger 18 is provided at the center of the frame body 11 in the front-rear direction on the two frame materials 12 b extending in the front-back direction in the upper frame 12. When the glass plate storage body 1 is lifted, a hook (for example, a crane or the like) is locked on the hoisting tools 18. In addition, the hanger 18 may be provided at a portion where two frame materials 12a extending in the left-right direction and two frame materials 12b extending in the front-rear direction are connected. A plurality of top rods 21 (three in the figure, but not limited to three) are provided on the upper frame 12 and extend in the arrangement direction of the glass plates G, that is, in the front-rear direction. Further, a plurality of bottom bars 22 (two are shown in the figure, but not limited to two) are provided on the lower frame 14 to extend in the arrangement direction of the glass plates G, that is, in the front-rear direction. The top rods 21 are arranged at regular intervals in the longitudinal direction of the frame 11, that is, in the left-right direction, two are arranged near both ends, and one is arranged at the center. The bottom bars 22 are respectively disposed between the top bars 20 in the left-right direction. Thereby, the top bar 21 and the bottom bar 22 are alternately arranged along the left-right direction. Furthermore, in FIG. 1, the top bar 21 and the bottom bar 22 are arranged so as to extend in the short-side direction of the frame 11, but it is not limited to this. 11 is arranged in a manner of extending in the long side direction. In this case, the plurality of glasses G are arranged in the direction of the arrow A and are housed. In addition, the interval between the top bar 21 and the bottom bar 22 may not necessarily be equal. FIG. 2 is a view of a glass plate container in which a glass plate container containing a glass plate is described, as viewed along an arrow D in FIG. 1. As shown in FIG. 2, a plurality of upper jigs (first jigs) 31 are provided on the upper portion of the frame 11. The upper jigs 31 hold one side edge of the glass plate G, that is, the first side edge G1. The upper clamps 31 are supported by the top rods 21, whereby the upper clamps 31 are spaced from each other and are provided along the first side edge G1 of the glass plate G (three in this example). Then, the first side edge G1 of the glass plate G is held and hung by the upper jigs 31 near the two ends and the center portion. In the longitudinal direction of each top bar 21, a plurality of upper jigs 31 are arranged at intervals. Thereby, the plurality of glass plates G are suspended by the upper jig 31 leaving a gap in the arrangement direction, that is, in the front-rear direction. A plurality of lower jigs (second jigs) 32 are provided at the lower portion of the frame 11. The lower jigs 32 hold the other side edge of the glass plate G opposite to the first side edge G1, that is, the second side edge G2. The lower jigs 32 are supported by the bottom bars 22, whereby a plurality of lower jigs 32 (two in this example) are provided along the second side edge G2 of the glass plate G. Furthermore, the second side edge G2 of the glass plate G is held between the positions held by the upper holder 31 in the left-right direction by the lower holders 32. In the longitudinal direction of each bottom bar 22, a plurality of lower jigs 32 are arranged at intervals. As a result, the plurality of glass plates G are held by the lower jig 32 leaving a gap in the arrangement direction, that is, the front-rear direction. Next, the structures of the upper jig 31 and the lower jig 32 will be described. In addition, since the upper jig 31 and the lower jig 32 have the same structure, the structure of the upper jig 31 is described here, and the description of the structure of the lower jig 32 is omitted. Fig. 3 is a front view showing an embodiment of a jig provided on an upper portion of a glass plate container. Fig. 4 is a side view showing an embodiment of a jig provided on the upper portion of the glass plate container. As shown in FIGS. 3 and 4, the upper clamp 31 includes a clamp body 41, a clamping plate 42, and a fastening bolt 43. The jig body 41 is formed in a U-shape having a pair of side plate portions 45 facing each other and a fixing plate portion 46 connecting one side edge of the side plate portions 45. At least one screw hole 45 a is formed in each side plate portion 45, and at least one fastening bolt 43 is screwed into the screw holes 45 a from the outside of the side plate portion 45. The clamping plates 42 are arranged between the two side plate portions 45 in the clamp body 41 such that the clamping plates 42 face each other. The pair of clamping plates 42 is provided with a cushioning material 61 on the facing surfaces 51 a of the clamping plates 42 facing each other. The cushioning material 61 is made of a material having heat resistance and flexibility or elasticity. For example, glass fiber is preferably used, and especially glass cloth including a woven fabric made of glass fiber having the same properties as the glass plate G. Since the at least one fastening bolt 43 is screwed in the state where the glass plate G is arranged between the clamping plates 42 facing each other, the glass plate G is clamped and held by the clamping plate 42 via the buffer material 61. hold. FIG. 5 is a front view showing another embodiment of the jig provided on the upper portion of the glass plate container. FIG. 6 is a side view showing another embodiment of the jig provided on the upper portion of the glass plate container. As shown in FIGS. 5 and 6, the upper clamp 31 includes a clamp body 41, a clamping plate 42, and a fastening bolt 43. The jig body 41 is formed in a U-shape having a pair of side plate portions 45 facing each other and a fixing plate portion 46 connecting one side edge of the side plate portions 45. At least one (two in FIG. 5 and FIG. 6) screw holes 45 a are formed on one side of a pair of side plate portions 45 facing each other, and at least one screw hole is screwed into the screw holes 45 a from the outside of the side plate portion 45. Securing bolts 43. The clamping plate 42 is disposed between the two side plate portions 45 in the clamp body 41. The surface 51 a of the clamping plate 42 that is in contact with the fastening bolt 43 is the surface 51 a on the opposite side, the surface 51 b of the side plate portion 45 opposite to the clamping plate 42, and the lower surface of the fixing plate portion 46 to surround the glass plate. In the G method, a buffer material 61 is provided. The cushioning material 61 is made of a material having heat resistance and flexibility or elasticity. For example, glass fiber is preferably used, and especially glass cloth including a woven fabric made of glass fiber having the same properties as the glass plate G. The buffer material 61 may be fixed to the holding plate 42, or may be provided separately from the holding plate 42. Since the at least one fastening bolt 43 is screwed in with the glass plate G disposed between the clamping plate 42 and the side plate portion 45, the glass plate G is held by the clamping plate 42 and the side plate portion 45 through the cushioning material 61. Hold and hold. A locking portion 46 a is provided at the central portion of the fixing plate portion 46 when the clamp body 41 is viewed from the front, and a supporting member 65 is locked at the locking portion 46 a. The support member 65 is a wire made of a material having flexibility and heat resistance, and the support member 65 made of the wire is fastened to the locking portion 46a. The support member 65 is fixed by being wound around a top bar 21 fixed to the frame 12 on the frame 11. Thereby, the upper jig 31 is supported by the top bar 21 fixed to the frame 12 on the frame 11 via the flexible supporting member 65. Further, in the lower jig 32, the supporting member 65 locked to the locking portion 46 a is wound around a bottom bar 22 fixed to the frame 14 below the frame body 11 and fixed. Thereby, the lower jig 32 is supported by the bottom bar 22 fixed to the frame 14 below the frame body 11 via the flexible supporting member 65. The width dimension of the upper jig 31 and the lower jig 32 is preferably set to about 20 mm to 60 mm. The fixing method of the clamp body 41 is not limited to this, and it may replace the supporting member 65 formed of a wire, and a hook may be provided at the central portion of the fixing plate portion 46 or the end of the supporting member 65 of the locking portion 46a The hook is hung on the top bar 21. Next, the manufacturing method of the chemically strengthened glass plate which is one Embodiment of the chemically strengthened glass plate accommodation body 1 of the said structure is demonstrated. In addition, the manufacturing method of the chemically strengthened glass plate according to this embodiment is not particularly limited, but for larger and thinner glass plates (for example, size: 2421 mm to 1200 mm × 1500 mm to 1000 mm, thickness: 0.3 mm to 0.4 mm) Useful for chemical strengthening. (Fixture Mounting Step) First, with respect to the glass plate G to be processed, the upper clamp 31 is mounted on one side edge, that is, the first side edge G1. Specifically, the first side edge G1 of the glass plate G is disposed between the clamping plate portions 51 of the respective clamping plates 42 and the fastening bolts 43 are screwed. Thereby, the glass plate G is clamped and grasped from both sides by the clamping plate portion 51. The upper jig 31 is attached to the vicinity of both ends and the center of the first side edge G1 of the glass plate G. Then, the lower jig 32 is mounted on the second side edge G2, which is the other side edge of the glass plate G opposite to the first side edge G1. Specifically, the second side edge G2 of the glass plate G is disposed between the clamping plate portions 51 of the respective clamping plates 42 and the fastening bolts 43 are screwed. Thereby, the glass plate G is clamped and grasped from both sides by the clamping plate portion 51. The lower clamp 32 is installed between the upper clamps 31 in the second side edge G2 of the glass plate G. After the lower jig 32 is attached to the glass plate G, the upper jig 31 may be attached to the glass plate G. (Hanging step) Next, the glass plate G is vertically arranged and placed in the frame such that the first side edge G1 on which the upper jig 31 is mounted becomes upward and the second side edge G2 on which the lower jig 32 is attached becomes downward. 11 inside. Then, for example, the support member 65 is inserted into the locking portion 46 a and wound around the top bar 21, and then tightened, whereby the upper jig 31 is supported by the top bar 21 of the upper frame 12 by the support member 65. . Thereby, the glass plate G is hung inside the frame body 11 so that one side edge thereof, that is, the first side edge G1 becomes upward. At this time, the upper jig 31 clamps and holds the glass plate G from both sides by the clamping plate portion 51 by screwing in the fastening bolt 43. Therefore, if the screw-in amount of each fastening bolt 43 is adjusted so that the holding position of the glass plate G is the center position in the front-rear direction (left-right direction in FIG. 4) in the upper clamp 31, the holding position of the glass plate G is The positions hung by the support member 65 are substantially uniform in the vertical direction. If so, it is possible to suppress the bending moment from acting on the portion of the suspended glass plate G held by the upper jig 31 as much as possible. Further, the lower jig 32 is supported by the bottom bar 22 of the lower frame 14 by the support member 65. Thereby, the second side edge G2, which is the other side edge of the glass plate G suspended inside the frame body 11, is held on the frame body 11. Furthermore, after the glass plate G is suspended, the lower jig 32 may be mounted on the second side edge G2 of the glass plate G, and the lower jig 32 may be supported on the bottom bar 22. Then, all the glass plates G to be processed are hung in the frame body 11 with the first side edge G1 upward, and the lower side edge G2 is held in the frame body 11. If so, each glass plate G is hung in the frame body 11 and is housed in the frame body 11 with a gap between them. (Chemical strengthening step) The glass plate G housed in the glass plate container 1 is subjected to various processes for chemical strengthening. In this chemical strengthening step, first, the glass plate storage body 1 is put into a preheating furnace, and a heat treatment (heat treatment) is performed. In the preheating furnace, it takes time to heat the glass plate G, and gradually raises the temperature. Then, the hanger 18 whose hook is locked on the glass plate container 1 is pulled up by a crane, and the glass plate container 1 is put into a molten salt storage tank storing molten salt, so that the glass plate G The glass plate container 1 is dipped in molten salt (salt bath treatment) in a suspended state. This salt bath treatment is a treatment in which alkali metal ions (typically Li ions and Na ions) having a smaller ionic radius on the glass surface are exchanged to a larger ionic radius by a temperature below the glass transition point by ion exchange. Alkali ions (typically K ions), thereby forming a compressive stress layer on the glass surface and a tensile stress layer inside the glass. After the salt bath treatment, the glass plate receiver 1 is pulled up from the molten salt storage tank and put into a slow cooling furnace to slowly cool the glass plate G (slow cooling treatment). The slow cooling process is, for example, supplying a controlled output heat to a necessary position in the slow cooling furnace by an electric heater, and gradually cooling the glass plate G carried in the slow cooling furnace to a temperature region close to normal temperature. This can prevent the glass plate G from warping or cracking. Next, the glass plate housing 1 is put into a washing tank, the glass plate G is washed, and finally, the surface of the glass plate G is rinsed with a water jet (washing treatment). Through the above steps, the glass plate G becomes a chemically strengthened glass plate after being chemically strengthened. Furthermore, in the salt bath treatment in the chemical strengthening step, if the load such as self-weight is concentrated on the glass plate G immersed in molten salt at a temperature below the glass transition point (for example, 400 ° C to 530 ° C), there is a low temperature in the glass plate G due to low temperature. Bending or strain caused by creep. However, according to the method for manufacturing a chemically strengthened glass plate according to this embodiment, while the glass plate G is suspended while immersed in molten salt to perform a salt bath treatment, it is possible to prevent the glass plate G from being affected by the salt bath treatment. Load caused by self-weight. Therefore, for example, compared with the case where the glass plate G is subjected to a salt bath treatment in a vertical state, the low-temperature creep caused by the load concentration such as self-weight is imparted to the lower end of the glass plate G in the salt bath treatment can be suppressed. Of deformation. Thereby, the large and thin glass plate G can be chemically strengthened with high quality and high yield, and the productivity of the chemically strengthened glass plate can be greatly improved. In addition, according to the chemically strengthened glass plate container 1 used in the method for manufacturing a chemically strengthened glass plate according to this embodiment, the upper side 31 holds one side edge of the glass plate G, that is, the first side edge G1. Put it into the molten salt in the state of hanging, and it is possible to perform a salt bath treatment on a plurality of glass plates G while suppressing the load caused by its own weight as much as possible. This makes it possible to chemically strengthen a large and thin glass plate G while suppressing deformation caused by low-temperature creep. In addition, the second side edge G2, which is the other side edge of the lower side of the glass plate G suspended by the upper fixture 31, is held by the lower jig 32, thereby suppressing the hanging of the glass plate G in the chemical strengthening step. The movement can prevent the glass plates G from contacting each other due to shaking, and also can prevent the glass plates G from being locally deformed. This makes it possible to perform chemical strengthening by performing a salt bath treatment without causing damage or local deformation due to the contact between adjacent glass plates G. In addition, by using a plurality of upper jigs 31 to hold the first side edge G1 on the upper side of the glass plate G and using a plurality of lower jigs 32 to hold the second side edge G2 on the lower side of the glass plate G, the upper portion can be used. The external force imparted when the gripper 31 and the lower gripper 32 are gripped is dispersed. Thereby, the influence of the external force given to the glass plate G by holding by the upper clamp 31 and the lower clamp 32 can be suppressed as much as possible. In addition, since the upper jig 31 and the lower jig 32 are supported by the frame 11 by a flexible supporting member 65, the upper jig 31 and the lower jig 32 are softly displaced following the shaking of the glass plate G and the like. This makes it possible to suppress external forces caused to the glass plate G from being shaken by the glass plate G, etc., at the portions held by the upper and lower clamps 31 and 32. Furthermore, in the chemical strengthening step, it is possible to suppress the glass plate from being deformed by bending or strain caused by low-temperature creep due to the weight of the glass plate. Furthermore, since the holding plate 42 that grips and holds the glass plate G in the upper and lower fixtures 31 and 32 includes the cushioning material 61, the glass plate G is not easily damaged when the glass plate G is held. In particular, if a glass cloth (glass fiber) having the same properties as the glass plate G is used as the cushioning material 61, since the thermal expansion coefficients of the glass plate and the cushioning material are approximately the same, it is possible to suppress as much as possible the temperature variation caused during the chemical strengthening step. Damage (causes cracking of the glass plate G or damage to the surface of the glass plate G). Furthermore, in the above-mentioned embodiment, the first side edge G1 of the glass plate G is held and hung by the plurality of upper fixtures 31, but the glass may also be held by a long upper fixture 31 over a substantially full length. The first side edge G1 of the plate G is held and hung. Similarly, instead of the plurality of lower jigs 32, the second side edge G2 of the glass plate G may be held by a long lower jig 32 over a substantially full length. Furthermore, in the above embodiment, the second side edge G2 of the lower side of the glass plate G suspended by the upper fixture 31 is held by the lower fixture 32, but as long as the glass plates G do not shake each other during the salt bath treatment, In the case of contact, the lower jig 32 need not be provided. For example, a partition wall interposed between the glass plates G may be erected from the bottom bar 22 to prevent the glass plates G from shaking and contacting each other. In the examples, a glass plate of G6 size (1800 mm × 1500 mm) and a thickness of 0.3 mm was supported by various supporting methods, and the glass plate was chemically strengthened, and the results after the chemical strengthening were evaluated. Furthermore, the glass plate is manufactured by a floating method in which molten glass is passed through molten tin to make a smooth glass plate. The molten tin side during the floating method forming is the lower surface side, and the floating type is used. The opposite side of the molten tin at the time of forming is the upper surface side. (1) Support method (1.1) Comparative Example 1 Place glass plates with the first side edge (one side edge) as the upper side and the second side edge (the other side edge) as the lower side, and place them at equal intervals. Place three bottom bars on the ground and keep the first side edge and the two end edges above to prevent the glass plate from falling down. (1.2) Example 1 The upper side clamp of a glass plate with a width dimension of 60 mm was used to hold the vicinity of both ends and the center of the first side edge of the glass plate and hang, and the lower side clamp of the glass plate was used to grip the glass plate with a width dimension of 60 mm. Between the positions in the second side edge held by the upper jig. (1.3) Example 2 The upper side clamp of the glass plate with a width dimension of 40 mm was used to hold the vicinity of both ends and the center of the first side edge of the glass plate and hang, and the lower side clamp of the glass plate was used to grip the glass plate with a width dimension of 40 mm. Between the positions in the second side edge held by the upper jig. (2) Chemical strengthening treatment The chemical strengthening is performed by immersing in a molten salt at 400 ° C for 4 hours with potassium nitrate (KNO ₃ ) as a main component. (3) Evaluation item (3.1) Strain The chemically strengthened glass plate was placed on a platen, and the appearance of the glass plate was checked for strain and other deformations and evaluated. (3.2) Lower surface side warpage Evaluation was performed by measuring the maximum value of warpage with respect to an imaginary plane in the lower surface side of the glass plate after chemical strengthening by a measuring tool. (3.3) Upper surface side warpage Evaluation was performed by measuring the maximum value of the warpage with respect to the virtual plane in the upper surface side of the glass plate after chemical strengthening by a gage. (3.4) Small piece warpage The glass plate after chemical strengthening is cut and processed into small pieces (156 mm × 77 mm), and the maximum value of the warpage in the small piece and the ratio of the area where the warpage is 0.3 mm or less are measured. Evaluation. (4) Evaluation results Table 1 shows the eligibility of each evaluation. [Table 1] The results of each evaluation item are as follows. (4.1) Evaluation result of strain (4.1.1) Comparative Example 1 It was confirmed that strain or depression existed in the entire surface, and the surface quality was not good in terms of appearance. As a result, the evaluation of strain was unacceptable (×). (4.1.2) Example 1 It can be confirmed that a slight warpage occurs in a portion held by the upper jig, but there is almost no strain in the entire surface, so that the surface quality is very good. As a result, the strain evaluation was passed (○). (4.1.3) Example 2 As in Example 1, it was confirmed that a slight warpage occurred in the portion held by the upper jig, but there was almost no strain in the entire surface, and the surface quality was very good. As a result, the strain evaluation was passed (○). (4.2) Evaluation results of warpage on the lower surface side (4.2.1) Comparative Example 1 A large warpage occurred at the contact portion with the bottom bar, and the maximum value of warpage was 1.35 mm. As a result, the evaluation of the lower surface side warp was unacceptable (×). (4.2.2) Example 1 There is no large warpage, and the maximum value of warpage is suppressed to 0.75 mm. As a result, the evaluation of the curvature of the lower surface side was a pass ((circle)). (4.2.3) Example 2 Similar to Example 1, there was no large warpage, and the maximum value of warpage was further suppressed to 0.55 mm. As a result, the evaluation of the curvature of the lower surface side was a pass ((circle)). (4.3) Evaluation results of warpage on the upper surface side (4.3.1) Comparative Example 1 There was no large warpage, and the maximum value of warpage was 0.37 mm. As a result, the evaluation of the warpage of the upper surface side was acceptable ((circle)). (4.3.2) In Example 1, the maximum value of the warpage was 0.45 mm. Since this is a warpage within an allowable range, the evaluation of the warpage on the upper surface side was acceptable (○). (4.3.3) Example 2 There is no large warpage, and the maximum value of warpage is suppressed to 0.15 mm. As a result, the evaluation of the warpage of the upper surface side was acceptable ((circle)). (4.4) Evaluation result of small piece warpage (4.4.1) Comparative Example 1 The maximum value of small piece warpage was 0.65 mm, and the ratio of the area with a warpage of 0.3 mm or less was 77.8%. As a result, the evaluation of the small piece warpage was unacceptable (×). (4.4.2) In Example 1, the maximum value of the warpage of the small piece was suppressed to 0.35 mm, and the ratio of the area where the warpage was 0.3 mm or less was 90.1% and a larger ratio. As a result, the evaluation of the small piece warpage was acceptable (○). (4.4.3) In Example 2, the maximum value of the warpage of the small pieces was suppressed to 0.20 mm, and the ratio of the area where the warpage was 0.3 mm or less was 100%. As a result, the evaluation of the small piece warpage was acceptable (○). (5) Conclusion According to the above evaluation results, in the case of chemical strengthening by the support method of Comparative Example 1, the load such as self-weight during salt bath treatment is concentrated on the second side edge (lower side edge) of the glass plate, The glass plate is deformed due to low temperature creep. On the other hand, it is considered that when chemical strengthening is performed by the support methods of Examples 1 and 2, the load such as self-weight in the salt bath treatment can be suppressed from being concentratedly imparted to the suspended glass plate, and therefore, low temperature can be suppressed. Deformation caused by creep. From this, it can be seen that in order to chemically strengthen large and thin glass plates with high quality and high yield, the manufacturing method of the present invention in which the glass plate is suspended in a salt bath treatment state is more effective. According to this manufacturing method, Can greatly improve the productivity of chemically strengthened glass plate. In addition, according to the evaluation results of Examples 1 and 2, it can be seen that, as the upper and lower clamps hang the glass plate in the salt bath treatment, the smaller the width, the more the deformation can be suppressed. However, if the width dimension of the upper jig and the lower jig is too small, the holding force may be concentratedly imparted to the glass plate and the glass plate G may be damaged or the deformation may increase. According to this situation, the width dimension of the upper jig and the lower jig is preferably set to about 20 mm to 60 mm. As mentioned above, the manufacturing method of the chemically strengthened glass plate of this invention, and the glass plate receiving body for chemical strengthening was demonstrated in detail, Of course, this invention is not limited to the above example, It can carry out within the range which does not deviate from the meaning of this invention Various improvements or changes. This application is based on Japanese Patent Application No. 2016-107494 filed on May 30, 2016, and incorporated herein by reference.

1‧‧‧ glass plate receiving body for chemical strengthening

11‧‧‧Frame

12‧‧‧ Upper frame

12a‧‧‧Frame

12b‧‧‧Frame

14‧‧‧ lower frame

14a‧‧‧Frame

14b‧‧‧Frame

14c‧‧‧ porous metal mesh

16‧‧‧Side Frame

18‧‧‧ spreader

21‧‧‧ top stick

22‧‧‧ bottom stick

31‧‧‧ Upper fixture (first fixture)

32‧‧‧ Lower fixture (second fixture)

41‧‧‧Jig body

42‧‧‧Clamping plate

43‧‧‧ Fastening bolt

45‧‧‧Side panel section

45a‧‧‧Screw hole

46‧‧‧Fixed plate section

46a‧‧‧Detent

51‧‧‧ clamping plate

51a‧‧‧ opposite

51b‧‧‧ surface

61‧‧‧Buffer material

65‧‧‧ supporting components

A‧‧‧arrow

B‧‧‧ Arrow

C‧‧‧ Arrow

D‧‧‧ Arrow

G‧‧‧ glass plate

G1‧‧‧First side edge

G2‧‧‧Second side edge

FIG. 1 is a schematic perspective view of a chemically strengthened glass plate container used in one embodiment of the method for manufacturing a chemically strengthened glass plate of the present invention. FIG. 2 is a view viewed in the direction of arrow D in the glass plate container of FIG. 1. FIG. 3 is a front view of one embodiment of the jig provided on the upper part of the glass plate container. Fig. 4 is a side view of an embodiment of a jig provided on the upper part of the glass plate container. FIG. 5 is a front view of another embodiment of the jig provided on the upper part of the glass plate container. FIG. 6 is a side view of another embodiment of the jig provided on the upper part of the glass plate container.

Claims (9)

A method for manufacturing a chemically strengthened glass plate, which is characterized by holding a first side edge of a glass plate, hanging the glass plate with the first side edge being held upward, and hanging the glass plate on one side The glass plate was chemically strengthened by being immersed in molten salt and subjected to a salt bath treatment. A glass plate receiving body for chemical strengthening is characterized in that: it is used in a method for manufacturing a chemically strengthened glass plate and is put into molten salt in a state in which a plurality of glass plates are stored; A plurality of glass plates are placed; and a first fixture is provided on the upper part of the frame, and hangs the glass plates while holding the first side edges of the glass plates and leaving a gap with each other. For example, the glass plate receiving body for chemical strengthening of claim 2, wherein a second jig is provided below the frame, and the second jig holds each of the glass plates being hung and faces the first side edge. Of the second side edge. For example, the glass sheet container for chemical strengthening of claim 2 or 3, wherein the first jigs are spaced apart from each other and a plurality of the first jigs are provided along the first side edge of the glass sheet. The chemically strengthened glass plate container according to any one of claims 2 to 4, wherein the first jig is supported by the frame through a flexible supporting member. The chemically strengthened glass plate container according to any one of claims 2 to 5, wherein the first jig includes: a pair of holding plates that hold and hold the glass plate; and a buffer material that Opposing surfaces of the holding plate and the glass plate are respectively disposed in the holding plates. For example, the glass-plate-accommodating body for chemical strengthening of claim 3, wherein the second jigs are spaced from each other and a plurality of the second jigs are provided along the second side edge of the glass plate. For example, the glass plate container for chemical strengthening of claim 3 or 4, wherein the second jig is supported by the frame through a flexible supporting member. The chemically strengthened glass plate container according to any one of claims 3 to 5, wherein the second jig includes: a pair of holding plates that hold and hold the glass plate; and a buffer material that Opposing surfaces of the holding plate and the glass plate are respectively disposed in the holding plates.