Glass plate processing method, glass plate

Abstract

The large plate has a first main surface and a second main surface, and is separated into a first small plate and a second small plate on a separation surface. The separation surface has a curved portion on a first intersection line intersecting with the first main surface and a second intersection line intersecting with the second main surface, respectively. In a top view, the first intersection line is arranged on one side of the second intersection line. On a cross section orthogonal to the first intersection line, the separation surface is inclined to a normal line of the first main surface. (1) Laser is focused inside the large plate to form a modified portion on the separation surface to be separated. (2) After the modified portion is formed, stress is applied to the large plate to form a crack on the separation surface. (3) After the crack is formed, the first small plate and the second small plate are offset in the normal direction of the first main surface to separate the first small plate and the second small plate.

Description

Technical Field

[0001] The invention relates to a processing method of a glass plate and a glass plate. Background Art

[0002] In Patent Document 1, a large plate as a glass plate is irradiated with laser light to form a plurality of fine cracks inside the large plate. The plurality of fine cracks are formed on a separation surface where the large plate is to be separated into a first small plate and a second small plate. Then, if stress is applied to the glass plate to form cracks on the separation surface, the large plate can be separated into the first small plate and the second small plate on the separation surface.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Japanese Patent Application Publication No. 2019-64916 Summary of the invention

[0006] Technical problem to be solved by the invention

[0007] In Patent Document 1, when a large plate is separated into a first small plate and a frame-shaped second small plate surrounding the first small plate, the second small plate is crushed into more fragments to obtain a first small plate.

[0008] One aspect of the present invention provides a technique for separating a large plate into a first small plate and a second small plate without breaking both the first small plate and the second small plate.

[0009] Technical means used to solve technical problems

[0010] A processing method for a glass plate according to one embodiment of the present invention is to separate a large plate as a glass plate having a first main surface and a second main surface opposite to the first main surface into a first small plate and a second small plate on a separation surface. The separation surface has a curved portion on a first intersection line intersecting with the first main surface and a second intersection line intersecting with the second main surface, respectively. In a top view, the first intersection line is arranged on one side of the second intersection line. On a cross section orthogonal to the first intersection line, the separation surface is inclined to a normal line of the first main surface. The processing method comprises the following (1) to (3). (1) A laser is focused inside the large plate to form a modified portion on the separation surface to be separated. (2) After the modified portion is formed, stress is applied to the large plate to form a crack on the separation surface. (3) After the crack is formed, the first small plate and the second small plate are offset in the normal direction of the first main surface to separate the first small plate and the second small plate.

[0011] Effects of the Invention

[0012] According to one aspect of the present invention, when separating a large plate into a first small plate and a second small plate, separation can be performed without breaking both the first small plate and the second small plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a flowchart showing the glass plate processing method according to the first embodiment.

[0014] Figure 2A It is shown Figure 1 Top view of S1.

[0015] Figure 2B It is shown Figure 1 The cross-sectional view of S1 is Figure 2A Cross-sectional view along line IIB-IIB.

[0016] Figure 3 It is shown Figure 1 Cross-sectional view of S2.

[0017] Figure 4 It is shown Figure 1 Cross-sectional view of S3.

[0018] Figure 5 It is shown Figure 1 Cross-sectional view of S4.

[0019] Figure 6 It is shown Figure 1 A cross-sectional view of the S5.

[0020] Figure 7 This is a flowchart showing a method for processing a glass plate according to the second embodiment.

[0021] Figure 8 It is shown Figure 7 Top view of the S6.

[0022] Fig. 9 It is a top view showing the separation surface of the glass plate according to the third embodiment. DETAILED DESCRIPTION

[0023] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In each figure, the same or corresponding components are marked with the same symbols, and their description is sometimes omitted. In the specification, "to" indicating a numerical range means that the numerical values ​​recorded before and after it are included as the lower limit and upper limit.

[0024] (Implementation Method 1)

[0025] like Figure 1 As shown, the processing method of the glass plate comprises S1 to S5. Figure 2A , Figure 2B , Figures 3 to 6,right Figure 1 S1 to S5 are described below.

[0026] first, Figure 1 In S1, Figure 2A and Figure 2B As shown, prepare a large plate 10. The large plate 10 is a glass plate. The large plate 10 may be a curved plate, but in the present embodiment, it is a flat plate. The large plate 10 has a first main surface 11 and a second main surface 12 opposite to the first main surface 11. When the large plate 10 is a curved plate, it may be a single curved shape curved in one direction, or a multi-curved shape curved in both the upper long side direction and the short side direction. When the large plate 10 is a single curved shape, the radius of curvature of the large plate 10 is preferably above 5000 mm and below 100000 mm. When the large plate 10 is a multi-curved shape, the radius of curvature of the large plate 10 is preferably above 1000 mm and below 100000 mm. The bending forming of the large plate 10 can be implemented by heating the glass plate to 550°C to 700°C to soften it. As a bending forming method of the large plate 10, gravity forming, pressure forming, roller forming, vacuum forming, etc. can be used.

[0027] The shapes of the first main surface 11 and the second main surface 12 are, for example, rectangular. The shapes of the first main surface 11 and the second main surface 12 may be trapezoidal, circular, elliptical, etc., without particular limitation.

[0028] like Figure 6 As shown, the large plate 10 is separated into the first small plate 20 and the second small plate 30 on the separation surface 13. Therefore, the first small plate 20 and the second small plate 30 are both smaller than the large plate 10. It does not matter which of the first small plate 20 and the second small plate 30 is larger.

[0029] For example, the first small plate 20 is a product and the second small plate 30 is a non-product, i.e., waste. Alternatively, the second small plate 30 is a product and the first small plate 20 is a non-product. Furthermore, the first small plate 20 and the second small plate 30 may both be products.

[0030] The large plate 10 is a glass plate, so the first small plate 20 and the second small plate 30 are of course both glass plates.

[0031] The uses of the glass plate as a product include, for example, automobile window glass, instrument panel, head-up display (HUD), instrument panel, center console, shift knob and other automobile interior parts cover glass, architectural window glass, display substrate or display cover glass. The thickness of the glass plate as a product can be appropriately set according to the product application, for example, 0.01 cm to 2.5 cm.

[0032] Glass sheets as products Figure 1 After S1 to S5, it can be laminated with another glass plate with an intermediate film to be used as laminated glass. Figure 1 After S1 to S5, the glass can be subjected to strengthening treatment and used as strengthened glass.

[0033] The glass of the product is, for example, soda-lime glass, alkali-free glass, chemically strengthened glass, etc. Chemically strengthened glass can be used as, for example, cover glass after chemical strengthening treatment. The glass of the product may also be air-cooled strengthened glass.

[0034] Glass sheets as products can be Figure 1 After the large plate 10 is bent and formed, the large plate 10 bent into a single curved shape or a multi-curved shape may be subjected to Figure 1 S1 to S5 are performed to obtain a glass plate as a product. That is, the glass plate as a product may be bent into a single curved shape or a multi-curved shape.

[0035] like Figure 2A and Figure 2B As shown, the separation surface 13 has a first intersection line 14 intersecting with the first main surface 11 and a second intersection line 15 intersecting with the second main surface 12. The first intersection line 14 has a curved portion, for example. The first intersection line 14 does not have a straight portion, but may have a straight portion as described later. The second intersection line 15 has a curved portion in the same manner as the first intersection line 14. The second intersection line 15 has a curved portion with the same center of curvature C as the first intersection line 14. The second small plate 30 includes a center of curvature C.

[0036] like Figure 2A As shown, in a top view, the first intersection line 14 is arranged on one side of the second intersection line 15. Specifically, the first intersection line 14 is arranged on the side of the curvature center C based on the second intersection line 15, that is, the radial inner side of the second intersection line. The arrangement of the first intersection line 14 and the second intersection line 15 can also be reversed, and the first intersection line 14 is arranged on the opposite side of the curvature center C based on the second intersection line 15, that is, the radial outer side of the second intersection line 15.

[0037] like Figure 2B As shown, in the cross section 16 orthogonal to the first intersection line 14, the separation surface 13 is inclined to the normal line N of the first main surface 11. The separation surface 13 is, for example, a linear trapezoid. The angle β between the normal line N of the first main surface 11 and the separation surface 13 is, for example, 3° to 45°.

[0038] If Β is above 3°, the details are as described below, but if Figure 6 As shown in FIG. 1 , the first small plate 20 and the second small plate 30 can be offset in the normal direction of the first main surface 11. On the other hand, if β is less than 45°, chipping on the separation surface 13 of the product can be suppressed. Figure 7 As shown, when S6 (chamfering) is further performed after S5, β is preferably 3° to 20°.

[0039] The separation surface 13 is a linear trapezoid in the present embodiment, but may be a non-linear trapezoid. In this case, β is the angle formed by the normal line N of the first main surface 11 and the tangent line of the separation surface 13. β may be within the above range.

[0040] then, Figure 1 In S2, Figure 3 As shown, the first laser LB1 is focused into a point shape inside the large plate 10, and a point-shaped modified portion D is formed at the focusing point. The first laser LB1 is a pulsed light, and the modified portion D is formed by nonlinear absorption. Nonlinear absorption is also called multiphoton absorption. The probability of multiphoton absorption is nonlinear with respect to the photon density (energy density of the first laser LB1), and the higher the photon density, the higher the probability. For example, the probability of two-photon absorption is proportional to the square of the photon density.

[0041] The pulse light preferably uses a pulse laser with a wavelength range of 250nm to 3000nm and a pulse width of 10fs to 1000ns. The laser with a wavelength range of 250nm to 3000nm can pass through the large plate 10 to a certain extent, so it can produce nonlinear absorption inside the large plate 10 to form a modified portion D. The wavelength range is preferably 260nm to 2500nm. In addition, if it is a pulse laser with a pulse width of less than 1000ns, it is easy to increase the photon density, and nonlinear absorption can be produced inside the large plate 10 to form a modified portion D. The pulse width is preferably 100fs to 100ns.

[0042] The light source of the first laser LB1 includes, for example, Nd-doped YAG crystal (Nd:YAG), which can emit laser light with a wavelength of 1064nm. The wavelength of the pulsed light is not limited to 1064nm. Nd:YAG second harmonic laser (wavelength 532nm) or Nd:YAG third harmonic laser (wavelength 355nm) can also be used. The light source of the first laser LB1 repeatedly emits a pulse group or a single pulse light.

[0043] The first laser LB1 is focused into a point shape by an optical system including a focusing lens, etc. The modified portion D is a portion of the glass where a density change or a refractive index change occurs. The modified portion D may be a void or a modified layer, etc. The modified layer is a layer where a density or a refractive index changes due to a structural change or due to melting and resolidification.

[0044] The two-dimensional movement of the focal point within a plane at a certain depth from the first main surface 11 and the change of the depth of the focal point from the first main surface 11 are repeated, so that the modified portion D is dispersedly arranged on the separation surface 13. The movement of the focal point is performed by, for example, a 3D galvano scanner, and when the change of the depth of the focal point is performed by moving the stage, a 2D galvano scanner can be used.

[0045] The stage is a component for carrying the large plate 10. The movement of the focal point can be implemented by moving or rotating the stage for carrying the large plate 10. As the stage, for example, an XYZ stage, an XYθ stage, an XYZ stage or an XYZθ stage can be used. The X-axis, the Y-axis and the Z-axis are orthogonal to each other, the X-axis and the Y-axis are parallel to the first main surface 11, and the Z-axis is perpendicular to the first main surface 11.

[0046] The modified portion D is formed in the entire thickness direction from the first main surface 11 to the second main surface 12. Here, the entire thickness direction refers to an area of ​​more than 80% of the thickness of the plate. In this area, multiple point-shaped modified portions D can be formed at intervals in the thickness direction of the plate, or a continuous linear modified portion D can be formed continuously. In short, Figure 1 In S3, cracks CR can be formed in the entire plate thickness direction.

[0047] When the first laser LB1 forms the modified portion D, it is focused into a linear shape in the direction of the optical axis by a filament or an optical system including a focusing lens. In this case, a linear modified portion D is formed. In addition, when the first laser LB1 forms the modified portion D, a multifocus optical system can be used to simultaneously generate multiple focusing points in the direction of the optical axis. Multiple point-shaped modified portions D are formed at the same time. These first lasers LB1 can be irradiated obliquely to the first main surface 11, and the optical axis of the first laser LB1 can also be on the separation surface 13.

[0048] Then, in Figure 1 In S3, such as Figure 4 As shown, stress is applied to the large plate 10, and a crack CR is formed on the separation surface 13. The formation of the crack CR starts from the first main surface 11 and is formed to the second main surface 12 with the modified portion D as the starting point.

[0049] In the formation of the crack CR, for example, thermal stress is applied to the plate 10 by irradiation of the second laser LB2. The second laser LB2 mainly generates linear absorption by irradiating the plate 10. Mainly generating linear absorption means that the heat generated by linear absorption is greater than the heat generated by nonlinear absorption. Nonlinear absorption hardly occurs. At any position of the plate 10, the photon density can be less than 1×10 8 W / cm 2 In this case, nonlinear absorption hardly occurs. The heat generated by the second laser LB2 forms a crack CR.

[0050] Linear absorption can be called single photon absorption. The probability of single photon absorption is proportional to the photon density. In the case of single photon absorption, according to the Lamber-Beer's law, the following equation (1) holds.

[0051] I=I0×exp(-α×L)・・・(1)

[0052] In the above formula (1), I0 is the intensity of the first laser LB1 on the first main surface 11, I is the intensity of the first substrate LB1 on the second main surface 12, L is the propagation distance of the first laser LB1 from the first main surface 11 to the second main surface 12, and α is the absorption coefficient of the glass to the first laser LB1. α is the absorption coefficient of linear absorption, which is determined by the wavelength of the first laser LB1 and the chemical composition of the glass.

[0053] α×L represents the internal transmittance. The internal transmittance is the transmittance when the first laser LB1 is not reflected on the first main surface 11. The smaller α×L is, the greater the internal transmittance is. α×L is, for example, less than 3.0, preferably less than 2.3, and more preferably less than 1.6. In other words, the internal transmittance is, for example, more than 5%, preferably more than 10%, and more preferably more than 20%. If α×L is less than 3.0, the internal transmittance is more than 5%, and both the first main surface 11 and the second main surface 12 are sufficiently heated.

[0054] From the viewpoint of heating efficiency, α×L is preferably 0.002 or more, more preferably 0.01 or more, and further preferably 0.02 or more. In other words, the internal transmittance is preferably 99.8% or less, more preferably 99% or less, and further preferably 98% or less.

[0055] If the temperature of the glass exceeds the annealing point, the glass is easily plastically deformed and the generation of thermal stress is limited. Therefore, the temperature of the glass can be reduced to below the annealing point by adjusting the wavelength of light, output power, beam diameter on the first main surface 11, etc.

[0056] The second laser LB2 is, for example, continuous wave light. The light source of the second laser LB2 is not particularly limited, and is, for example, a Yb fiber laser. The Yb fiber laser is a laser in which Yb is doped in the core of an optical fiber, and emits continuous wave light of a wavelength of 1070 nm.

[0057] The second laser light LB2 may be pulse light instead of continuous wave light.

[0058] The second laser LB2 is irradiated onto the first main surface 11 through an optical system including a condenser lens and the like. The second laser LB2 may be irradiated onto the first main surface 11 at an angle. At this time, the optical axis of the second laser LB2 may be on the separation surface 13. By moving the irradiation point of the second laser LB2 along the first intersection line 14, a crack CR may be formed on the entire separation surface 13. The crack CR separates the large plate 10 into the first small plate 20 and the second small plate 30.

[0059] The irradiation point can be moved by, for example, a 2D galvano scanner or a 3D galvano scanner. In addition, the irradiation point can also be moved by moving or rotating the stage that carries the large plate 10. As the stage, for example, an XYZ stage, an XYθ stage, an XYZ stage, or an XYZθ stage can be used.

[0060] In this embodiment, thermal stress is applied to the plate 10 by irradiation with the second laser beam LB2, but there is no particular limitation on the method of applying stress to the plate 10. The plate 10 may be pressed with a roller to apply stress to the plate 10.

[0061] In order to make the crack CR easily bend along the curved portion of the first intersection line 14, the curvature radius of the curved portion is, for example, 0.5 mm or more, preferably 1.0 mm or more. In addition, the curvature radius of the curved portion is, for example, 1000 mm or less, preferably 500 mm or less.

[0062] Then, in Figure 1 In S4, Figure 5 As shown, a temperature difference is given to the first small plate 20 and the second small plate 30, and a gap G is formed between the first small plate 20 and the second small plate 30. The friction between the glasses can be suppressed.

[0063] If the temperature of the portion on the side of the center of curvature C (e.g., the second small plate 30) based on the curved portion of the first intersection line 14 is lower than the temperature of the portion on the opposite side of the center of curvature C (e.g., the first small plate 20), a gap G is formed between the first small plate 20 and the second small plate 30. The portion on the side of the center of curvature C may be cooled, and the portion on the opposite side of the center of curvature C may be heated.

[0064] It is also possible not to implement Figure 1 S4, but then Figure 1 S3 Implementation Figure 1 S5.

[0065] Then, in Figure 1 In S5, Figure 6 As shown in FIG. 1 , the first small plate 20 and the second small plate 30 are offset in the normal direction of the first main surface 11 to separate the first small plate 20 and the second small plate 30. As described above, Figure 2A As shown, the first intersection line 14 is arranged on one side of the second intersection line 15 when viewed from above. In the cross section 16 orthogonal to the first intersection line 14, as shown in FIG. Figure 2B As shown, the separation surface 13 is inclined to the normal line N of the first main surface 11 . For example, the separation surface 13 is in a shape that becomes thinner vertically upward, and the vertical direction is the normal line direction of the first main surface 11 .

[0066] Therefore, the first small plate 20 and the second small plate 30 can be staggered in the normal direction of the first main surface 11. Figure 2AThe first intersection line 14 of the first main surface 11 shown includes a curved portion, so that even when the first small plate 20 and the second small plate 30 cannot be offset in a direction parallel to the first main surface 11, the first small plate 20 and the second small plate 30 can be separated without breaking both of them.

[0067] Since the first small plate 20 is a product and the second small plate 30 is a non-product, the separation surface 13 is in a shape that becomes thinner and thinner vertically upward so that the non-product can be pulled out by gravity. In the case where the first small plate 20 is a non-product and the second small plate is a product, the trapezoid of the separation surface 13 can be reversed, and the separation surface 13 can be in a shape that becomes thinner and thinner vertically downward. When the first small plate 20 is a window glass for a car or a cover glass for a car interior component, the inclination angle β of the separation surface 13 is determined according to the installation angle when the first small plate 20 is installed on the glass of the car, thereby further reducing the loss of electromagnetic waves received and transmitted by the sensor or millimeter wave radar or other accessory components that can transmit and receive electromagnetic waves arranged on the second main surface 22 of the first small plate 20.

[0068] Next, refer to Figure 6 , the first small plate 20 as a product is described. The first small plate 20 has a first main surface 21, a second main surface 22, and an inclined surface 23. The first main surface 21 of the first small plate 20 is a part of the first main surface 11 of the large plate 10. Similarly, the second main surface 22 of the first small plate 20 is a part of the second main surface 12 of the large plate 10. The inclined surface 23 of the first small plate 20 is a surface generated by the crack CR of the separation surface 13.

[0069] The second small plate 30 also has a first main surface 31, a second main surface 32, and an inclined surface 33, similarly to the first small plate 20. The first main surface 31 of the second small plate 30 is the remaining portion of the first main surface 11 of the large plate 10. Similarly, the second main surface 32 of the second small plate 30 is the remaining portion of the first main surface 11 of the large plate 10. The inclined surface 33 of the second small plate 30 is a surface generated by the crack CR of the separation surface 13.

[0070] (Implementation Method 2)

[0071] like Figure 7 As shown, the processing method of the glass sheet can further include S6 after S5. Figure 8 right Figure 7 The S6 is described below. Figure 7 S1~S5 and Figure 1 S1 to S5 are the same, so their description is omitted. Figure 7 The S4 can be used with Figure 1 The S4 is implemented similarly, and then Figure 7 S3 Direct Implementation Figure 7 S5.

[0072] Figure 7 In S6, Figure 8 As shown, the angle formed by the inclined surface 23 of the first small plate 20 and the first main surface 21 is cut to form a first chamfered surface 24 at the angle. Similarly, the angle formed by the inclined surface 23 of the first small plate 20 and the second main surface 22 is cut to form a second chamfered surface 25 at the angle. The chamfering process can be performed by a machining center or the like. The chamfering can be a so-called C chamfer, but in this embodiment, it is an R chamfer.

[0073] Next, refer to Figure 8 , the first small plate 20 as a product is described. The first small plate 20 is a glass plate, so the first small plate 20 is also referred to as the glass plate 20 below. The glass plate 20 has a first main surface 21, a second main surface 22, an inclined surface 23, a first chamfered surface 24, and a second chamfered surface 25. Since the first chamfered surface 24 and the second chamfered surface 25 are formed, the glass plate 20 can be suppressed from breaking.

[0074] (Implementation method 3)

[0075] In the above-mentioned Embodiment 1 and Embodiment 2, if Figure 2A As shown, the first intersection line 14 and the second intersection line 15 are respectively closed. Therefore, the first small plate 20 and the second small plate 30 cannot be offset in the direction parallel to the first main surface 11.

[0076] In this embodiment, if Fig. 9 As shown, the first intersection line 14 and the second intersection line 15 are opened respectively. The first intersection line 14 and the second intersection line 15 are respectively opened at two ends. Figure 2A is consistent in (in other words, does not exist), but Fig. 9 The middle is separated.

[0077] Fig. 9 The first intersection line 14 shown is opened to divide the first main surface 11 into two areas, intersecting at two points on the periphery of the first main surface 11. The distance L1 between the two ends of the first intersection line 14 is less than or equal to twice the average curvature radius R1 of the curved portion of the first intersection line 14 (twice in this embodiment).

[0078] same, Fig. 9 The second intersection line 15 shown is opened to divide the second main surface 12 into two areas, intersecting at two points on the periphery of the second main surface 12. The distance L2 between the two ends of the second intersection line 15 is less than 2 times the average curvature radius R1 of the curved portion of the second intersection line 15 (2 times in this embodiment).

[0079] When L1 is less than 2 times of R1 and L2 is less than 2 times of R2, the first small plate 20 and the second small plate 30 are unlikely to be offset in the direction parallel to the first main surface 11 because the width of the outlet is narrow. Example

[0080] Hereinafter, a specific example of the method for processing a glass plate will be described.

[0081] [Example 1]

[0082] In Example 1, the implementation Figure 1 S1 to S5. In S1, a soda-lime glass with a thickness of 3.5 mm is prepared as a large plate 10. The first main surface 11 is a rectangle with a length of 200 mm and a width of 100 mm. The separation surface 13 is a cone surface that becomes thinner and thinner vertically upward. The angle β formed by the normal line of the first main surface 11 and the separation surface 13 is 4°. The first intersection line 14 is a circle with a radius of 22.5 mm.

[0083] In S2, Figure 3 As shown, the first laser LB1 is focused into a point shape inside the large plate 10, and a point-shaped modified portion D is formed at the focusing point. The two-dimensional movement of the focusing point within a plane at a certain depth from the first main surface 11 and the change of the focusing point depth from the first main surface 11 are repeated, so that the modified portion D is dispersedly arranged on the separation surface 13. The movement of the focusing point uses an XYZ stage.

[0084] The irradiation conditions of the first laser light LB1 in S2 are as follows.

[0085] Oscillator: Green pulse laser (Explorer532-2Y, Spectra-Physics, USA)

[0086] Oscillation mode: pulse oscillation (single shot)

[0087] Light wavelength: 532nm

[0088] Output power: 2W

[0089] Excitation frequency: 10kHz

[0090] Scanning speed in the plane direction: 100 mm / sec

[0091] Irradiation spacing in the plane direction: 0.01mm

[0092] Irradiation spacing in depth direction: 0.05mm

[0093] Focus beam diameter: 4μm

[0094] Pulse energy: 200 μJ

[0095] In S3, Figure 4As shown, stress is applied to the large plate 10, and a crack CR is formed on the separation surface 13. In the formation of the crack CR, thermal stress is applied to the large plate 10 by irradiation with the second laser LB2. The second laser LB2 is irradiated onto the first main surface 11 through an optical system including a focusing lens, etc. The irradiation point moves along the first intersection line 14, thereby forming a crack CR on the entire separation surface 13. The movement of the irradiation point uses an XYZ stage.

[0096] The irradiation conditions of the second substrate LB2 in S3 are as follows.

[0097] Oscillator: Yb fiber laser (IPG Photonics, YLR500)

[0098] Oscillation mode: continuous wave oscillation

[0099] Light wavelength: 1070nm

[0100] Output power: 340W

[0101] Scanning speed in the plane direction: 70 mm / sec

[0102] Beam diameter on the first principal surface 11: 1.2 mm

[0103] In S4, Figure 5 As shown, a temperature difference is given to the first small plate 20 and the second small plate 30, and a gap G is formed between the first small plate 20 and the second small plate 30. Specifically, the cooling mist is sprayed on the second small plate 30 for 10 seconds.

[0104] In S5, Figure 6 As shown, the first small plate 20 and the second small plate 30 are offset in the normal direction of the first main surface 11 to separate the first small plate 20 and the second small plate 30. Specifically, the second small plate 30 is pulled vertically downward by gravity. Then, after the first small plate 20 as a product is grasped and transported by a transport robot, no breakage is confirmed on the inclined surface 23 of the first small plate 20.

[0105] [Example 2]

[0106] In Example 2, the processing of the large plate 10 was carried out under the same conditions as in Example 1, except that the angle β formed by the normal line of the first main surface 11 and the separation surface 13 was changed to 21°. As a result, the second small plate 30 could be pulled vertically downward by gravity as in Example 1. In addition, after the first small plate 2 as a product was transported, no breakage was confirmed on the inclined surface 23 of the first small plate 20.

[0107] [Example 3]

[0108] In Example 3, the processing of the large plate 10 was carried out under the same conditions as in Example 1, except that the angle β formed by the normal line of the first main surface 11 and the separation surface 13 was changed to 45°. As a result, the second small plate 30 could be pulled vertically downward by gravity as in Example 1. In addition, after the first small plate 2 as a product was transported, no breakage was confirmed on the inclined surface 23 of the first small plate 20.

[0109] [Example 4]

[0110] In Example 4, the processing of the large plate 10 was carried out under the same conditions as in Example 1, except that the angle β formed by the normal line of the first main surface 11 and the separation surface 13 was changed to 60°. As a result, the second small plate 30 could be pulled vertically downward by gravity as in Example 1. In addition, after the first small plate 2 as a product was transported, it was confirmed that the inclined surface 23 of the first small plate 20 was broken.

[0111] [Example 5]

[0112] In Example 5, the processing of the large plate 10 was carried out under the same conditions as in Example 1, except that the angle β formed by the normal line of the first main surface 11 and the separation surface 13 was changed to 2°. As a result, unlike in Example 1, the second small plate 30 could not be pulled vertically downward by gravity. Therefore, it is of course impossible to transport the first small plate 2 after pulling it out.

[0113] [Summarize]

[0114] Table 1 shows the evaluation results of Examples 1 to 5.

[0115]

[0116] As is clear from Table 1, in Examples 1 to 3, β was within the range of 3° to 45°, and separation was possible without collapse during transportation. However, in Example 4, β was too large, so collapse occurred during transportation. In addition, in Example 5, β was too small, so separation was impossible.

[0117] The above describes the processing method and processed glass plate of the present invention, but the present invention is not limited to the above-mentioned embodiments, etc. Various changes, modifications, substitutions, additions, reductions and combinations can be made within the scope of the claims. These also fall within the technical scope of the present invention.

[0118] This patent application claims the priority based on Japanese Patent Application No. 2019-210500 filed with the Japan Patent Office on November 21, 2019, and all the contents of Japanese Patent Application No. 2019-210500 are hereby incorporated by reference into this patent application.

[0119] Explanation of symbols

[0120] 10 large plates

[0121] 11. First main surface

[0122] 12 Second main surface

[0123] 13 Separation surface

[0124] 14 First intersection

[0125] 15 Second intersection

[0126] 20 First Small Board

[0127] 30 Second small board

[0128] LB1 First Laser

[0129] D Modification Department

[0130] CR Crack

Claims

1. A method for processing a glass plate, comprising separating a large glass plate having a first main surface and a second main surface opposite to the first main surface into a first small plate and a second small plate on a separation surface, wherein: The separation surface has a curved portion on a first intersection line with the first main surface and a second intersection line with the second main surface, respectively. In a plan view, the first intersection line is arranged on one side of the second intersection line, On a cross section orthogonal to the first intersection line, the separation surface is inclined to the normal line of the first main surface, The first laser light which is pulse light is focused inside the large plate, and a modified portion is formed on the separation surface to be separated by nonlinear absorption. After the modified part is formed, the large plate is irradiated with a second laser to mainly produce linear absorption. Applying thermal stress to the large plate to make its temperature reach below the annealing point, forming cracks on the separation surface, α×L is above 0.002 and below 3.0, Wherein L is the propagation distance of the second laser from the first main surface to the second main surface, α is the absorption coefficient of the glass to the second laser, After the crack is formed, the first small plate and the second small plate are offset in the normal direction of the first main surface to separate the first small plate from the second small plate.

2. The method for processing a glass plate according to claim 1, wherein: The first laser light is focused into a spot shape inside the large plate, and a plurality of spot-shaped modified portions are formed on the separation surface to be separated.

3. The method for processing a glass plate according to claim 1, wherein: When forming the modified portion, the first main surface is irradiated with the first laser beam at an angle.

4. The processing method according to any one of claims 1 to 3, wherein The first intersection line and the second intersection line are respectively closed.

5. The processing method according to any one of claims 1 to 3, wherein: The first intersection line and the second intersection line are open to each other, and a distance between two ends of the first intersection line is less than or equal to two times an average radius of curvature of the curved portion of the first intersection line.

6. The processing method according to any one of claims 1 to 3, wherein: The curvature radius of the curved portion of the first intersection line is greater than or equal to 0.5 mm and less than or equal to 1000 mm.

7. The processing method according to any one of claims 1 to 3, wherein: The photon density of the second laser at any position of the large plate is less than 1×10 8 W / cm 2 .

8. The processing method according to any one of claims 1 to 3, wherein: After the crack is formed and before the first small plate and the second small plate are displaced from each other, a temperature difference is applied to the first small plate and the second small plate to form a gap between the first small plate and the second small plate.

9. The processing method according to any one of claims 1 to 3, wherein: The angle between the inclined surface of the first small plate caused by the crack and the first main surface of the first small plate is cut to form a chamfered surface at the angle.

10. The processing method according to any one of claims 1 to 3, wherein: The angle between the inclined surface of the first small plate caused by the crack and the second main surface of the first small plate is also cut to form a chamfered surface at the angle.

11. The processing method according to any one of claims 1 to 3, wherein: The large plate is a curved plate.

12. The processing method according to any one of claims 1 to 3, wherein: The glass plate is a window glass for automobiles or a cover glass for automobile interior parts.

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