WO2021131421A1

WO2021131421A1 - Glass plate manufacturing method and glass plate

Info

Publication number: WO2021131421A1
Application number: PCT/JP2020/043041
Authority: WO
Inventors: 佑太和田; 愛信星野; 松本　直之
Original assignee: 日本電気硝子株式会社
Priority date: 2019-12-23
Filing date: 2020-11-18
Publication date: 2021-07-01
Also published as: CN114585475A; JP7415267B2; KR20220113352A; JP2021098258A; TW202126427A

Abstract

This glass plate manufacturing method includes: a first processing step S1 for processing an end section GE of a glass plate G with a first grindstone 1; and a second processing step S2 for polishing, with a second grindstone 2, the end section GE of the glass plate G that has undergone the first processing step S1. In the second processing step S2, while the second grindstone 2 is relatively moved in the longitudinal direction of the end section GE of the glass plate G, the second grindstone 2 is relatively moved in the thickness direction of the glass plate G.

Description

Glass plate manufacturing method and glass plate

The present invention relates to a glass plate and a method for manufacturing the same.

A glass plate is used for displays such as liquid crystal displays and organic EL displays. If there is a scratch on the edge of the glass plate, cracks or the like are generated from the scratch, and in order to prevent this, the edge of the glass plate is ground and polished.

For example, Patent Document 1 describes a grinding process in which a glass plate is chamfered with a grinding wheel while being conveyed in a predetermined direction, and the edge of the chamfered glass plate is polished. A method for processing a glass plate including a polishing process for performing a polishing process with a grindstone is disclosed.

JP-A-2018-103320

For example, when a glass plate is used as a display substrate, the end of the glass plate may be pressed against a pin or a roller for positioning in the process of manufacturing an electronic device on the substrate. At that time, if scratches remain on the edge of the glass plate, glass powder is likely to be generated. If this glass powder adheres to the surface of the glass plate, it causes disconnection failure of the electronic device. Therefore, it is desired to further improve the surface texture of the end portion of the glass plate.

However, if the surface texture of the entire edge of the glass plate is improved, the entire edge becomes mirror-like, and it becomes difficult to detect the edge when the edge of the glass plate is imaged with a camera.

The present invention has been made in view of the above circumstances, and it is a technical subject to enable detection by a camera while reducing the generation of glass powder at the edge of a glass plate.

The present invention is for solving the above-mentioned problems, and is a method for manufacturing a glass plate having a surface and an end portion, wherein the end portion of the glass plate has an end face, the end face and the surface. A first processing step of processing the end portion of the glass plate with a first grindstone having a connecting surface formed between the glass plates, and a second grindstone of the end portion of the glass plate that has undergone the first processing step. In the second processing step, the second grindstone is moved relative to the length direction of the end portion of the glass plate, and the second grindstone is moved to the glass. It is characterized in that it is moved relative to the thickness direction of the plate.

According to this configuration, in the second processing step, the second grindstone is mainly moved in the thickness direction of the glass plate while being relatively moved in the length direction of the end portion of the glass plate. The end face is processed, and the surface roughness of the end face becomes smaller than the surface roughness of the connecting surface. Since the positioning pins and rollers come into contact with the end faces having a small surface roughness, the generation of glass powder can be reduced. Further, when the end portion of the glass plate is imaged with a camera, the end surface has a mirror surface shape, but the connection surface has a non-mirror surface shape, so that the end portion can be detected based on the connection surface.

Here, if the entire edge of the glass plate is polished, the abrasive grains are likely to be melted due to the processing heat, the grindstone is heavily consumed, and the surface texture is rather deteriorated. In the second processing step described above, since the end face is mainly processed, the processing heat can be reduced and the melting damage of the abrasive grains can be suppressed. Therefore, the consumption of the grindstone can be reduced, and the surface texture of the end face can be further improved.

In the method for manufacturing a glass plate according to the present invention, the second grindstone has a groove for polishing the end face of the glass plate, and the groove is formed on a bottom portion of the glass plate in contact with the end face and a bottom portion thereof. The bottom portion of the groove portion has a width larger than the thickness of the end surface of the glass plate, and has a regulating surface that is connected and can be contacted with the connection surface. The width of the bottom portion may be smaller than the sum of the thickness of the end face and the relative moving distance of the second grindstone in the thickness direction.

According to such a configuration, by setting the width of the bottom portion of the second grindstone to the groove portion in the above range, the bottom portion of the groove portion of the glass plate while the second grindstone is moved relative to the glass plate. The end face can be suitably polished and the connecting surface of the glass plate can be brought into contact with the regulating surface of the groove. This makes it possible to stably process the end portions of a plurality of glass plates when they are manufactured.

In the method for manufacturing a glass plate according to the present invention, the second grindstone has an outer peripheral surface on which no groove is formed before the second processing step is executed, and in the second processing step, the second processing step is performed. The end portion of the glass plate may be polished by the outer peripheral surface of the grindstone.

If a groove is formed on the outer peripheral surface of the second grindstone, only the groove can be used for machining on the outer peripheral surface, and the number of glass plates that can be machined with a single second grindstone is reduced. If a second grindstone having an outer peripheral surface without a groove is used, most of the outer peripheral surface can be used for machining, and the number of glass plates that can be machined with a single second grindstone can be significantly increased. it can.

The present invention is for solving the above-mentioned problems, and is a glass plate having a surface and an end portion, wherein the end portion is an end face and a connecting surface formed between the end face and the surface. The surface roughness Ra1 of the end surface is smaller than the surface roughness Ra2 of the connection surface.

According to this configuration, the strength of the end face of the glass plate can be increased and the product quality can be improved. Further, since the positioning pins and rollers come into contact with the end faces having a small surface roughness, the generation of glass powder can be reduced. Furthermore, when the end of the glass plate is imaged with a camera, the end surface is mirror-like, but the connection surface is non-mirror surface, so it is possible to detect the end based on the connection surface. Become.

In the above glass plate, the ratio Ra1 / Ra2 of the surface roughness Ra1 of the end surface to the surface roughness Ra2 of the connection surface may be 0.15 to 0.6. According to such a configuration, since the difference in reflectance between the end surface and the connection surface becomes large, it becomes easy to detect the end portion based on the connection surface when the end portion of the glass plate is imaged by the camera.

Further, the surface roughness Ra1 of the end face may be 0.06 μm or less. According to such a configuration, it is possible to surely reduce the generation of glass powder due to the contact between the positioning pin and the roller.

According to the present invention, it is possible to detect the edge of the glass plate with a camera while reducing the generation of glass powder.

It is a perspective view which shows the manufacturing method of the glass plate which concerns on 1st Embodiment. It is sectional drawing which shows the 1st grindstone and the glass plate. It is sectional drawing which shows the 1st processing process. It is sectional drawing which shows the 2nd grindstone and the glass plate. It is a figure which shows the locus of movement of the 2nd grindstone. It is sectional drawing which shows the 2nd processing process. It is sectional drawing which shows the 2nd processing process. It is sectional drawing which shows the 2nd processing process. It is a figure which shows another example which concerns on the locus of movement of the 2nd grindstone. It is a figure which shows another example concerning the locus of movement of the 2nd grindstone. It is sectional drawing which shows the 2nd processing process. It is sectional drawing which shows the 2nd processing process. It is sectional drawing which shows the manufacturing method of the glass plate which concerns on 2nd Embodiment. It is sectional drawing which shows the 2nd processing process. It is sectional drawing which shows the 2nd processing process. It is sectional drawing which shows the 2nd processing process. It is sectional drawing which shows the 2nd processing process.

Hereinafter, a mode for carrying out the present invention will be described with reference to the drawings. 1 to 12 show the first embodiment of the method for manufacturing a glass plate according to the present invention.

In the following example, a case where a rectangular glass plate G having four sides is manufactured will be described, but the shape of the glass plate G is not limited to the present embodiment. The glass plate G is molded by a known molding method such as a float method, an overflow down draw method, or a slot down draw method, and is cut into a predetermined size. The thickness T of the glass plate G is 0.2 to 10 mm, and the size of the glass plate G is 200 mm × 300 mm to 3100 mm × 3500 mm, but the size is not limited to this range. The composition of the glass plate G is preferably non-alkali glass or aluminosilicate glass. Here, the "non-alkali glass" is a glass that does not substantially contain an alkaline component (alkali metal oxide), and specifically, a glass having a weight ratio of an alkaline component of 1000 ppm or less. The weight ratio of the alkaline component is preferably 500 ppm or less, more preferably 300 ppm or less.

As shown in FIG. 1, the glass plate G has a first surface GS1, a second surface GS2, and end portions GE corresponding to each side. In this embodiment, a case where the end GE related to two parallel sides of the four sides of the glass plate G is processed is illustrated. Each end GE of the glass plate G includes a machining start end GEa and a machining end end GEb.

As shown in FIG. 1, in this method, the first processing step S1 in which the end portion GE of the glass plate G is processed by the first grindstone 1 and the end portion GE of the glass plate G are secondly processed after the first processing step S1. A second processing step S2 for processing with the grindstone 2 is provided. Note that XYZ in the figure is a Cartesian coordinate system. The X-axis direction and the Y-axis direction are horizontal directions, and the Z-axis direction is a vertical direction (vertical direction).

In the first processing step S1 and the second processing step S2, by relatively moving the

grindstones

1 and 2 and the glass plate G, each end GE of the glass plate G is moved in the length direction (X-axis direction). Machining is performed from the machining start end GEa to the machining end end GEb along the above. For example, by moving the glass plate G along the transport direction GX1, the end portion GE of the glass plate G can be processed by the

grindstones

1 and 2. Alternatively, the end portion GE of the glass plate G may be processed by moving the

grindstones

1 and 2 in a predetermined direction GX2.

The first grindstone 1 used in the first processing step S1 is composed of, for example, a pair of rotary grindstones. The first grindstone 1 is, for example, a grinding grindstone that chamfers the end GE of the glass plate G. As the first grindstone 1, for example, an electrodeposition grindstone in which diamond abrasive grains are hardened with a metal electrodeposition bond and a metal bond grindstone in which the abrasive grains are hardened with a metallic binder are preferably used.

The first grindstone 1 is configured to be movable in the horizontal direction (X-axis direction and Y-axis direction) and the vertical direction (Z-axis direction) by a moving mechanism. Further, the first grindstone 1 is rotated around its axis RC1 by a driving means such as an electric motor.

As shown in FIGS. 1 and 2, the first grindstone 1 has a first groove portion 3 for processing the end portion GE of the glass plate G. The first groove portion 3 has a bottom portion 3a and inclined surfaces 3b formed on both sides of the bottom portion 3a. In the present embodiment, the first grindstone 1 in which the first groove portion 3 of one stage is formed is illustrated, but the present invention is not limited to this configuration, and the first groove portion 3 of a plurality of stages may be formed in the first grindstone 1. Further, the first processing step S1 may be performed on each end GE of the glass plate G by a plurality of first grindstones 1.

As shown in FIG. 2, the end portion GE of the glass plate G supplied to the first processing step S1 is composed of an end face including the corner portion GC. In the first processing step S1, the corner GC of each end GE is removed by chamfering the first grindstone 1.

Specifically, as shown in FIG. 3, the first grindstone 1 grinds the end portion GE of the glass plate G by the bottom portion 3a and the inclined surface 3b. In this case, the inclined surface 3b removes the corner portion GC of the end portion GE of the glass plate G. By executing this first processing step S1, the end GE of the glass plate G is ground by the end face ES1 (top) ground by the bottom 3a of the first grindstone 1 and the inclined surface 3b of the first grindstone 1. It is provided with the connection surface ES2.

The end face ES1 is formed in a flat surface shape or a curved surface shape following the shape of the bottom portion 3a of the first grindstone 1. The connecting surface ES2 is a boundary portion formed between the end surface ES1 and the respective surfaces GS1 and GS2 of the glass plate G. The connecting surface ES2 is formed in a curved surface so as to connect the respective surfaces GS1 and GS2 of the glass plate G and the end surface ES1.

The second grindstone 2 used in the second processing step S2 is composed of, for example, a pair of rotary grindstones for polishing the end face ES1 of the glass plate G. As the second grindstone 2, a resin bond grindstone in which a resin binder (resin bond) is used as the binder for the abrasive grains is preferably used.

It is preferable to use a thermosetting resin as the resin binder. As a specific example, a phenol resin, an epoxy resin, a polyimide resin, a polyurethane resin or the like can be adopted as the resin binder.

As the abrasive grains bonded to the second grindstone 2, one selected from diamond particles, aluminum oxide particles, silicon carbide particles, cubic boron nitride particles, metal oxide particles, metal carbide particles, metal nitride particles and the like is selected. Alternatively, two or more types can be selected and mixed. The particle size of the abrasive grains is, for example, # 1000 to 3000, but is not limited to this range.

The second grindstone 2 is configured to be movable in the horizontal direction (X-axis direction, Y-axis direction) and the vertical direction (Z-axis direction) by a moving mechanism. Further, the second grindstone 2 is rotated around its axis RC2 by a driving means such as an electric motor.

As shown in FIG. 4, the second grindstone 2 has a second groove portion 4 on the outer peripheral surface 2a thereof for polishing the end portion GE of the glass plate G. The second groove portion 4 can receive substantially all of the end portion GE of the glass plate G, and the width dimension W1 of the second groove portion 4 is larger than the thickness dimension T of the glass plate G. The second groove portion 4 has a bottom portion 4a that contacts the end surface ES1 of the glass plate G and a pair of regulation surfaces 4b that are connected to both sides of the bottom portion 4a. The second groove portion 4 may be configured to receive a part of the end portion GE of the glass plate G (for example, the connecting surface ES2 on the end surface ES1 and the end surface ES1 side). In this case, the width dimension W1 of the second groove portion 4 is larger than the maximum thickness of the portion of the end portion GE that is accepted by the second groove portion 4.

The bottom portion 4a is formed on the end surface of the glass plate G in a curved surface shape or a flat surface shape so as to correspond to ES1. The regulation surface 4b is configured to have a curved surface shape so as to correspond to the connection surface ES2 of the glass plate G.

The width dimension W2 of the bottom portion 4a is larger than the thickness T1 of the end face ES1 of the glass plate G. The width dimension W2 of the bottom portion 4a is preferably 1 to 2.5 times (T1 ≦ W2 ≦ 2.5 T1) of the thickness dimension T1 of the end face ES1 related to the glass plate G.

In the present embodiment, the second grindstone 2 in which the second groove portion 4 of one stage is formed is illustrated, but the present invention is not limited to this configuration, and the second groove portion 4 of a plurality of stages may be formed in the second grindstone 2. Further, the second processing step S2 may be performed on each end GE of the glass plate G by a plurality of second grindstones 2.

In the second processing step S2, the second grindstone 2 is relatively moved from the processing start end GEa of the glass plate G toward the processing end end GEb in the length direction (X-axis direction) of the end GE. The second grindstone 2 is moved relative to the thickness direction (Z-axis direction) of the glass plate G.

FIG. 5 shows the movement locus of the second grindstone 2 in the second processing step S2. The second grindstone 2 moves relative to the glass plate G from the machining start position XS to the machining end position XE via the first intermediate position XM1 and the second intermediate position XM2 in the X-axis direction. The machining start end portion GEa of the glass plate G comes into contact with the second groove portion 4 of the second grindstone 2 at the machining start position XS. At the processing end position XE, the second grindstone 2 reaches the processing end end GEb of the glass plate G.

The second grindstone 2 reciprocates in the Z-axis direction while moving from the machining start position XS to the machining end position XE in the X-axis direction. That is, the second grindstone 2 moves (rises) a distance L1 from the reference position R0 in the Z-axis direction to reach the first position Z1. After that, the same distance L1 is moved (descended) to return to the reference position Z0, and then the distance L2 is moved (descended) from the reference position Z0 to reach the second position Z2.

In the present embodiment, the moving distance L1 from the reference position Z0 to the first position Z1 and the distance L2 from the reference position Z0 to the second position Z2 are equal to each other, but the relationship is not limited to this.

In this case, the sum (L1 + L2) of the moving distances L1 and L2 from the reference position Z0 is the moving range of the second grindstone 2 in the Z-axis direction. The width dimension W1 of the second groove portion 4 of the second grindstone 2 before (initially) the second processing step S2 is executed may be smaller than the sum of this movement range (L1 + L2) and the thickness dimension T of the glass plate G. Preferred (W1 <(L1 + L2 + T)). Further, the width dimension W2 of the bottom portion 4a of the second groove portion 4 before (initially) the second processing step S2 is executed is larger than the sum of this movement range (L1 + L2) and the thickness dimension T1 of the end face ES1 of the glass plate G. It is preferably small (W2 <(L1 + L2 + T1)).

Hereinafter, a specific operation mode of the second grindstone 2 in the second processing step S2 will be described with reference to FIGS. 5 to 8.

As shown in FIG. 5, the second grindstone 2 is arranged at the reference position Z0 in the Z-axis direction at the machining start position XS.

As shown in FIG. 6, when the processing start end portion GEa of the glass plate G reaches the second grindstone 2, the second groove portion 4 of the second grindstone 2 at the reference position Z0 is in the groove width direction (Z axis) at the bottom portion 4a. The central portion of the direction) comes into contact with the end face ES1 of the glass plate G. In this case, the connection surface ES2 of the glass plate G is not in contact with the regulation surface 4b of the second groove portion 4. That is, a gap is formed between the connection surface ES2 and the regulation surface 4b of the second groove portion 4.

As shown in FIG. 5, the second grindstone 2 rises from the reference position Z0 at a constant velocity in the Z-axis direction while moving from the machining start position XS to the first intermediate position XM1, and reaches the first position Z1. To reach. During this movement, the glass plate G is in a state where only the end surface ES1 is in contact with the bottom portion 4a of the second groove portion 4 of the second grindstone 2.

When the second grindstone 2 reaches the first position Z1, the connection surface ES2 on the second surface GS2 side of the glass plate G becomes the lower side of the second groove portion 4 at the first position Z1 as shown in FIG. Contact the regulatory surface 4b. In this case, when the connection surface ES2 is pressed against the regulation surface 4b, the glass plate G is elastically deformed in the Z-axis direction. As a result, the connection surface ES2 on the second surface GS2 side of the glass plate G is polished by the regulation surface 4b of the second groove portion 4.

After that, the second grindstone 2 moves at a constant speed from the first position Z1 to the reference position Z0 in the Z-axis direction while moving from the first intermediate position XM1 to the second intermediate position XM2. Further, as shown in FIG. 5, the second grindstone 2 moves at a constant speed from the reference position Z0 to the second position Z2 in the Z-axis direction while moving from the second intermediate position XM2 to the machining end position XE. ..

While the second grindstone 2 moves from the first position Z1 (first intermediate position XM1) to the second position Z2 (machining end position XE), only the end face ES1 of the glass plate G is the second in the second grindstone 2. It is in contact with the bottom portion 4a of the groove portion 4.

When the second grindstone 2 reaches the second position Z2, the connection surface ES2 on the first surface GS1 side of the glass plate G is restricted to the upper side of the second groove portion 4 at the second position Z2 as shown in FIG. Contact surface 4b. In this case, when the connection surface ES2 is pressed against the regulation surface 4b, the glass plate G is elastically deformed in the Z-axis direction. As a result, the connection surface ES2 on the first surface GS1 side of the glass plate G is polished by the regulation surface 4b of the second groove portion 4.

Since the end face ES1 is mainly machined in the second processing step S2, the surface roughness Ra1 (arithmetic mean roughness) of the end face ES1 is the surface roughness of the connecting surface ES2 in the glass plate G after the completion of the second processing step S2. It is smaller than Ra2 (arithmetic mean roughness). The ratio Ra1 / Ra2 of the surface roughness Ra1 of the end surface ES1 to the surface roughness Ra2 of the connection surface ES2 is preferably 0.15 to 0.6. The surface roughness Ra1 of the end face ES1 is preferably 0.03 to 0.06 μm. The surface roughness Ra2 of the connecting surface ES2 is preferably 0.1 to 0.2 μm.

In the present invention, the surface roughness Ra1 of the end face ES1 is measured at a plurality of locations (for example, around the machining start position XS, around the machining end position XE, and around their intermediate positions) where the positions of the end face ES1 in the length direction are different. And let it be the average value of them. Further, the surface roughness Ra2 of the connecting surface ES2 is measured at a plurality of locations where the positions of the end surface ES1 in the length direction are different, and is set as the maximum value thereof.

9 and 10 show other examples of the movement locus of the second grindstone 2 in the second processing step S2.

In the example shown in FIG. 9, the second grindstone 2 passes through the first intermediate position XM1 to the fifth intermediate position XM5 before moving from the machining start position XS to the machining end position XE.

While moving from the machining start position XS to the first intermediate position XM1, the second grindstone 2 does not move in the Z-axis direction (while maintaining the reference position Z0) and is relatively relative along the X-axis direction. Moving. The second grindstone 2 moves (rises) from the reference position Z0 to the first position Z1 in the Z-axis direction while moving from the first intermediate position XM1 to the second intermediate position XM2. While the second grindstone 2 moves from the machining start position XS to the second intermediate position XM2 via the first intermediate position XM1, only the end face ES1 of the glass plate G is polished by the bottom portion 4a of the second groove portion 4.

While moving from the second intermediate position XM2 to the third intermediate position XM3, the second grindstone 2 moves relatively along the X-axis direction while maintaining the first position Z1 in the Z-axis direction. During this movement, the end surface ES1 of the glass plate G is polished by the bottom portion 4a of the second groove portion 4, and the connection surface ES2 on the second surface GS2 side is polished to the lower regulation surface 4b of the second groove portion 4.

The second grindstone 2 moves from the first position Z1 to the reference position Z0 in the Z-axis direction while moving from the third intermediate position XM3 to the fourth intermediate position XM4. At the time of this movement, the connection surface ES2 on the second surface GS2 side of the glass plate G is separated from the regulation surface 4b of the second groove portion 4.

The second grindstone 2 moves from the reference position Z0 to the second position Z2 in the Z-axis direction while moving from the fourth intermediate position XM4 to the fifth intermediate position XM5. While the second grindstone 2 moves from the third intermediate position XM3 to the fifth intermediate position XM5 via the fourth intermediate position XM4, only the end face ES1 of the end surface GE of the glass plate G is polished by the bottom 4a of the second groove portion 4. Will be done.

While moving from the fifth intermediate position XM5 to the machining end position XE, the second grindstone 2 moves relatively along the X-axis direction while maintaining the second position Z2 in the Z-axis direction. During this movement, the end surface ES1 of the glass plate G is polished by the bottom portion 4a of the second groove portion 4, and the connection surface ES2 on the first surface GS1 side is polished to the upper regulation surface 4b of the second groove portion 4.

In the example shown in FIG. 10, the second grindstone 2 passes from the first intermediate position XM1 to the eighth intermediate position XM8 while moving from the machining start position XS to the machining end position XE.

The second grindstone 2 moves from the reference position Z0 to the second position Z2 in the Z-axis direction while moving from the machining start position XS to the first intermediate position XM1. The second grindstone 2 moves from the second position Z2 to the reference position Z0 in the Z-axis direction while moving from the first intermediate position XM1 to the second intermediate position XM2.

The second grindstone 2 moves from the reference position Z0 to the first position Z1 in the Z-axis direction while moving from the second intermediate position XM2 to the third intermediate position XM3. The second grindstone 2 moves from the first position Z1 to the reference position Z0 in the Z-axis direction while moving from the third intermediate position XM3 to the fourth intermediate position XM4. The second grindstone 2 cycles the same movement as above while moving from the fourth intermediate position XM4 to the fifth intermediate position XM5, the sixth intermediate position XM6, the seventh intermediate position XM7, and the eighth intermediate position XM8. Repeat.

When the above-mentioned second processing step S2 is repeatedly executed on a plurality of glass plates G, the depth of the second groove portion 4 of the second grindstone 2 increases due to the falling of abrasive grains. FIG. 11 is a cross-sectional view of the second grindstone 2 when the second processing step S2 is executed a plurality of times. In this case, the depth dimension D1 of the second groove portion 4 is deeper than the initial depth dimension D0.

FIG. 12 is a cross-sectional view of the second grindstone 2 when the second processing step S2 is further executed a plurality of times by the second groove portion 4 shown in FIG. In this case, the depth dimension D2 of the second groove portion 4 is further deeper than the depth dimension D1 in FIG. As shown in FIG. 12, the bottom portion 4a of the second groove portion 4 is formed so that its radius of curvature increases from the initial curved surface shape, that is, approaches a flat surface shape by repeating the second processing step S2. It will be gradually deformed.

As described above, in the second processing step S2, the second grindstone 2 is relatively moved in the Z-axis direction so that the regulation surface 4b of the second groove portion 4 always contacts the connection surface ES2 of the glass plate G. ing. As a result, even when the second processing step S2 is repeatedly executed as described above, the reduction of the width dimension W2 of the bottom portion 4a can be suppressed, and the processing accuracy of the end face ES1 of the end portion GE can be improved in each glass plate G. Can be kept constant.

The glass plate manufactured in this way is supplied to, for example, a display panel manufacturing process. In the process of manufacturing an electronic device on the first surface GS1, for example, the position of the end GE may be detected by photographing the end GE with a camera. In this case, the image of the end portion GE captured shows the end face ES1 and the connection surface ES2 having different surface roughness Ra1 and Ra2. As described above, by carrying out the second processing step S2, the surface roughness Ra1 of the end surface ES1 at the end portion GE of the glass plate becomes smaller than the surface roughness Ra2 of the connection surface ES2. Thereby, in the captured image, the end surface ES1 and the connection surface ES2 can be easily distinguished. Further, since the connection surface ES2 which is the boundary between each surface GS1 and GS2 of the glass plate G and the end portion GE can be easily specified, the end portion GE can be easily detected in the image.

Further, in the process of manufacturing an electronic device on the first surface GS1, a positioning pin or a roller may come into contact with the end surface ES1 of the glass plate G. Since the surface roughness Ra of the end face ES1 is small, it is possible to reduce the generation of glass powder due to this contact.

According to the method for manufacturing the glass plate G according to the present embodiment described above, by polishing the end GE of the glass plate G in the second processing step S2, glass powder is generated on the end GE of the glass plate G. It becomes possible to easily perform detection with a camera while reducing the number of cases.

If the width dimension W2 of the bottom portion 4a related to the second groove portion 4 of the second grindstone 2 is made larger than the thickness dimension T1 of the end face ES1 on the glass plate G, a new second grindstone at the time of replacement work of the second grindstone 2. The alignment work of 2 can be performed efficiently.

13 to 17 show a second embodiment of the method for manufacturing a glass plate according to the present invention. In this embodiment, the embodiment of the second processing step is different from that of the first embodiment.

As shown in FIG. 13, the second groove portion 4 illustrated in the first embodiment is not formed on the outer peripheral surface 2a of the second grindstone 2 before (unused) the second processing step S2 is executed.

As shown in FIG. 14, when the first glass plate G1 comes into contact with the outer peripheral surface 2a in the first second processing step S2 in the present embodiment, the second grindstone 2 is changed to the glass plate as in the first embodiment. With respect to G1, it moves relative to the length direction (X-axis direction) of the end GE from the machining start end GEa to the machining end end GEb, and also in the Z-axis direction (thickness direction of the first glass plate G1). Move relative to. As shown in FIG. 15, the second groove portion 4 having the width dimension W3 and the depth dimension D3 is formed on the second grindstone 2 by the first second processing step S2.

The depth dimension D3 of the second groove portion 4 is smaller than the initial depth dimension D0 of the second groove portion 4 in the first embodiment. That is, the second groove portion 4 according to the first embodiment has a function that the regulation surface 4b regulates the end portion GE of the glass plate G when the glass plate G is processed. The second groove portion 4 does not have this function.

When the second second processing step S2 is performed, as shown in FIG. 15, one end portion (upper end portion) of the second groove portion 4 in the groove width direction (Z-axis direction) of the second grindstone 2 is the second. It is arranged so as to overlap the end face ES1 of the second glass plate G2. In this case, the end surface ES1 of the second glass plate G2 comes into contact with the outer peripheral surface 2a of the second grindstone 2 in which the second groove portion 4 is not formed.

After that, the second grindstone 2 is in the length direction of the end portion GE from the processing start end portion GEa of the second glass plate G2 toward the processing end portion GEb, as in the case of processing the first glass plate G1. While moving relative to (X-axis direction), it moves relative to the Z-axis direction as shown in FIG. The width of the second groove portion 4 formed by processing the first glass plate G1 is expanded by processing the second glass plate G2. As shown in FIG. 17, the width dimension W4 of the second groove portion 4 after processing the second glass plate G2 is larger than the width dimension W3 of the second groove portion 4 immediately after processing the first glass plate G1. Become. In this case, the depth dimension D3 of the second groove portion 4 is substantially the same as that after the completion of the first second processing step S2.

In the third second processing step S2, the second grindstone 2 is arranged so as to overlap one end in the groove width direction (Z-axis direction) in the second groove portion 4 after processing the second glass plate G2. (See FIG. 17). In this case, the end surface ES1 of the third glass plate G3 comes into contact with the outer peripheral surface 2a of the second grindstone 2 in which the second groove portion 4 is not formed.

After that, the second grindstone 2 is moved relative to the thickness direction (Z-axis direction) of the glass plate G3 to polish the end face ES1 in the same manner as when the second glass plate G2 is processed. As a result, the width of the second groove portion 4 of the second grindstone 2 in the present embodiment is first increased as the second processing step S2 is repeated. When the second groove portion 4 spreads over the entire outer peripheral surface 2a of the second grindstone 2, the second grindstone 2 is arranged at the same position as the first second processing step S2, and a part of the second groove portion 4 increases the depth. Let me. Subsequently, by repeating the second processing step S2 while changing the position of the second grindstone 2, the entire second groove portion 4 is made to have the same depth.

The methods for producing the glass plates G1 to G3 according to the present embodiment have the following advantages as compared with the first embodiment. When the second groove portion 4 is formed on the outer peripheral surface 2a of the second grindstone 2 as in the first embodiment, only the second groove portion 4 of the outer peripheral surface 2a can be used for processing, and a single second grindstone 2 The number of glass plates G that can be processed in is reduced. On the other hand, if the second grindstone 2 having the outer peripheral surface 2a on which the second groove portion 4 is not formed is used as in the present embodiment, most of the outer peripheral surface 2a can be used for processing, and a single grindstone can be used. The number of glass plates G that can be processed by the second grindstone 2 can be significantly increased.

The present invention is not limited to the configuration of the above embodiment, and is not limited to the above-mentioned action and effect. The present invention can be modified in various ways without departing from the gist of the present invention.

In the above embodiment, an example in which the first processing step S1 and the second processing step S2 are performed on the two-sided end GE of the rectangular glass plate G is shown, but the remaining two side ends are shown. The present invention can also be applied to the part GE.

The relative movement of the second grindstone 2 in the Z-axis direction in the second processing step S2 may be executed by moving the glass plate G with respect to the Z-axis direction (thickness direction).

1 1st whetstone 2 2nd whetstone 4 2nd groove ES1 end surface ES2 connection surface G glass plate GE glass plate end GS1 1st surface GS2 2nd surface S1 1st processing process S2 2nd processing process

Claims

A method of manufacturing a glass plate having a surface and an edge.
The end portion of the glass plate has an end face and a connecting surface formed between the end face and the surface.
A first processing step of processing the end portion of the glass plate with a first grindstone and a second processing step of polishing the end portion of the glass plate that has undergone the first processing step with a second grindstone are provided.
In the second processing step, the second grindstone is moved relative to the thickness direction of the glass plate while the second grindstone is relatively moved in the length direction of the end portion of the glass plate. A method for manufacturing a glass plate.
The second grindstone has a groove for polishing the end face of the glass plate.
The groove portion has a bottom portion that contacts the end surface of the glass plate and a regulation surface that connects to the bottom portion and can contact the connection surface.
The bottom of the groove has a width larger than the thickness of the end face of the glass plate.
The glass according to claim 1, wherein the width of the bottom portion before executing the second processing step is smaller than the sum of the thickness of the end face and the relative moving distance of the second grindstone in the thickness direction. How to make a board.
Before executing the second processing step, the second grindstone has an outer peripheral surface on which no groove is formed.
The method for manufacturing a glass plate according to claim 1, wherein in the second processing step, the end portion of the glass plate is polished by the outer peripheral surface of the second grindstone.
A glass plate with a surface and edges
The end has an end face and a connecting surface formed between the end face and the surface.
A glass plate characterized in that the surface roughness Ra1 of the end surface is smaller than the surface roughness Ra2 of the connection surface.
The glass plate according to claim 4, wherein the ratio Ra1 / Ra2 of the surface roughness Ra1 of the end face to the surface roughness Ra2 of the connecting surface is 0.15 to 0.6.
The glass plate according to claim 4 or 5, wherein the surface roughness Ra1 of the end face is 0.06 μm or less.