Method for producing glass article, and glass article

Abstract

The present invention relates to the production of a glass article by: setting a virtual line on a main surface of a glass base material including a glass substrate having a thickness t of 0.4 mm or larger; irradiating the main surface with laser light along the virtual line to cut the glass base material; separating a portion surrounded by the virtual line from the glass base material to obtain a glass plate; and grinding the cut surface of the glass plate with a grindstone to obtain the glass article. The virtual line has a starting point and an ending point which are located at edge surfaces of the glass base material, and has either a shape having a locus depressed inward in an in-plane direction of the main surface of the glass base material or a shape having a closed curve. The virtual line has a perimeter of 60 mm or longer. The cut surface of the glass plate has a damaged layer having a width D satisfying relationship (1) formed by the irradiation with the laser light, and the damaged layer is removed by grinding with a grindstone. (1): 0.2·t≤D≤2,000 μm

Description

Glass article manufacturing method and glass article

[0001] The present invention relates to a method for manufacturing a glass article and a glass article.

[0002] A method for obtaining a glass article by irradiating glass with a laser beam to cut the glass is known. For example, Patent Document 1 describes irradiating a material with a pulsed laser beam to form a fault line, and then cutting the material along the fault line. In this case, the material can be cut along the fault line by applying an external stress to the fault line to break the material. Patent Document 1 also describes that the material can be cut by irradiating IR laser beam along the fault line. Another known method involves cutting glass by scraping it off with a grinding wheel such as a diamond wheel.

[0003] Patent No. 6552503

[0004] In recent years, there has been a demand for cutting relatively large shapes with a circumference of 60 mm or more from glass with a thickness of 0.4 mm or more, such as for cover glass for in-vehicle displays, vehicle window glass, and vehicle sensor cover glass, in order to cut out the outer shape of a product or to create holes for installing components inside the product. To cut out such large shapes, applying external stress along a fault line formed using pulsed laser light to cut the glass increases the contact area of ​​the cut surface of the glass, increasing friction between the cutout portion and the surrounding glass plates, which may result in failure to separate the cutout portion. Even if separation is possible, the high frictional force during separation may result in a deterioration in the quality of the cut surface. Furthermore, if cutting such large shapes by grinding the glass with a grinding wheel, the processing time may be excessive.

[0005] The present invention has been made in consideration of the above-mentioned problems, and aims to provide a method for manufacturing a glass article and a glass article that can efficiently obtain a glass article of a desired shape while suppressing deterioration in quality.

[0006] a cutting surface of the glass plate that is surrounded by the imaginary line and has a shape that is a closed curve, and the imaginary line has a start point and an end point located on an end face of the glass plate, and the imaginary line has a shape that has a locus that is recessed inward in an in-plane direction on the main surface of the glass plate, and the perimeter of the imaginary line is 60 mm or more; a damage layer is formed on the cut surface of the glass plate by the cutting caused by the irradiation of the laser light; a width D of the damage layer satisfies the following formula (1); and the damage layer is removed by grinding with the grinding wheel. 0.2·t≦D≦2000 μm (1) where t is the thickness (μm) of the glass base material.

[0007] A glass article according to the present disclosure includes a first glass substrate having a thickness of 0.4 mm or more, a second glass substrate having a thickness of 0.4 mm or more, and an intermediate layer provided between the first glass substrate and the second glass substrate, wherein openings having a circumferential length of 60 mm or more are formed in the first glass substrate and the second glass substrate, the openings in the first glass substrate and the second glass substrate overlap when viewed in the thickness direction of the glass article, and the amount of misalignment between an end face of the opening in the first glass substrate and an end face of the opening in the second glass substrate in an in-plane direction of the glass article is 100 μm or less.

[0008] According to the present invention, a glass article having a desired shape can be obtained efficiently while suppressing deterioration in quality.

[0009] FIG. 1 is a flowchart showing a manufacturing flow of a glass article according to the present embodiment. FIG. 2 is a schematic cross-sectional view of a glass base material according to the first embodiment. FIG. 3 is a schematic view showing an example of a virtual line according to the present embodiment. FIG. 4 is a schematic view illustrating irradiation of a glass base material with laser light. FIG. 5 is a schematic view illustrating irradiation of a glass base material with laser light. FIG. 6 is a schematic view of a glass plate. FIG. 7 is a schematic view illustrating grinding of a glass plate. FIG. 8 is a schematic view of a glass article. FIG. 9 is a schematic view showing a virtual line according to Modification 1. FIG. 10 is a schematic view showing a virtual line according to Modification 2. FIG. 11 is a schematic view of a glass article according to Modification 2. FIG. 12 is a schematic cross-sectional view of a glass base material according to the second embodiment. FIG. 13 is a schematic cross-sectional view of a glass plate according to the second embodiment. FIG. 14 is a schematic top view of a glass article according to the second embodiment. FIG. 15 is a schematic cross-sectional view of a glass article according to the second embodiment. FIG. 16 is a schematic view of a grinding wheel according to the second embodiment. FIG. 17 is a schematic diagram of a grinding wheel according to the second embodiment.

[0010] Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Note that the present invention is not limited to these embodiments, and when there are multiple embodiments, the present invention also includes configurations that are made by combining the respective embodiments. Furthermore, numerical values ​​include the range of rounding.

[0011] (First embodiment) (Method for manufacturing glass article) In the method for manufacturing a glass article 20T according to this embodiment, a portion surrounded by an imaginary line R is cut out from a glass base material 1 to obtain a glass plate 20, and the glass plate 20 is ground to manufacture the glass article 20T.

[0012] The glass plate 20 is a cut portion of the glass base material 1. The glass plate 20 used to obtain the glass article 20T may be the cut-out portion of the glass base material 1 (the portion surrounded by the imaginary line R), or may be the portion remaining after cutting out the glass base material 1 (the portion excluding the cut-out portion). In the following examples, the portion remaining after cutting out the glass base material 1 will be described as the glass plate 20 used to obtain the glass article 20T.

[0013] The glass article 20T in this embodiment is an in-vehicle glass that is mounted on a vehicle. The glass article 20T may be provided in an in-vehicle display device and used as a cover material for the surface of the in-vehicle display device, or may be used as a window member for the vehicle. When used as a window member for the vehicle, the glass article 20T may be used as the windshield of the vehicle V, in other words, as a windshield. However, the use of the glass article 20T is arbitrary, and it may be used for purposes other than in-vehicle use.

[0014] Fig. 1 is a flowchart showing a manufacturing flow of a glass article according to this embodiment. As shown in Fig. 1, when manufacturing a glass article 20T, a glass base material 1 is prepared (step S10), a virtual line R is set on a main surface 10A of the glass base material 1 (step S12), a laser beam L is irradiated onto the main surface 10A along the virtual line R to obtain a glass plate 20 (step S14), and a cut surface 20C of the glass plate 20 is ground to obtain a glass article 20T (step S16). Each step will be described in detail below.

[0015] (Preparation of Glass Preform) FIG. 2 is a schematic cross-sectional view of a glass preform according to the first embodiment. In this manufacturing method, first, a glass preform 1 is prepared. The glass preform 1 is a plate-shaped member. Note that the term "plate-shaped" here is not limited to being flat, and may have a curved surface, and may refer to a structure in which the width of the main surface is longer than the thickness. The glass preform 1 includes a glass substrate 10 that is a transparent glass plate. Here, "transparent" may refer to the transmission of visible light. The glass preform 1 may be a laminated glass in which multiple glass substrates 10 are stacked, but in the example of this embodiment, as shown in FIG. 1, it is a glass plate having a single glass substrate 10.

[0016] Hereinafter, one main surface of the glass base material 1 will be referred to as main surface 10A, the main surface opposite to main surface 10A will be referred to as main surface 10B, and the end surface (side surface) connecting main surface 10A and main surface 10B will be referred to as end surface 10C. In this embodiment, the glass base material 1 is made of a single glass substrate 10, so one main surface of the glass substrate 10 can be referred to as main surface 10A, and the other main surface of the glass substrate 10 can be referred to as main surface 10B. The thickness direction of the glass base material 1, i.e., the direction connecting main surface 10B and main surface 10A, will be referred to as the Z direction. The direction perpendicular to the Z direction (the left-right direction in the example of FIG. 2 ) will be referred to as the X direction, and the direction perpendicular to the Z direction and the X direction (the direction perpendicular to the paper surface in the example of FIG. 2 ) will be referred to as the Y direction. Furthermore, one direction along the X direction (the right direction in the example of FIG. 2) is designated as direction X1, the other direction along the X direction (the left direction in the example of FIG. 2) is designated as direction X2, one direction along the Y direction (the direction toward the back of the paper in the example of FIG. 2) is designated as direction Y1, the other direction along the Y direction (the direction toward the front of the paper in the example of FIG. 2) is designated as direction Y2, one direction along the Z direction (the direction from main surface 10B toward main surface 10A) is designated as direction Z1, and the other direction along the Z direction (the direction from main surface 10A toward main surface 10B) is designated as direction Z2. Note that the Z direction here may be a direction perpendicular to main surface 10A at the center position of glass base material 1.

[0017] Here, the thickness of the glass substrate 10 is referred to as thickness t. When the glass base material 1 is made of a single glass substrate 10, thickness t refers to the thickness of the glass base material 1 itself. When the glass base material 1 includes a plurality of glass substrates 10, thickness t refers to the thickness of one glass substrate 10. The thickness t of the glass base 10 is 0.4 mm or more, preferably 0.7 mm or more and 5.0 mm or less, and more preferably 0.8 mm or more and 3.0 mm or less. Note that thickness t refers to the length in the Z direction from the main surface 10A to the main surface 10B.

[0018] 2, the glass base material 1 (glass substrate 10) has a rectangular flat plate shape when viewed from the Z direction, but the shape of the glass base material 1 (glass substrate 10) may be any shape. For example, the glass base material 1 (glass substrate 10) is not limited to being rectangular when viewed from the Z direction, and may be polygonal, circular, elliptical, or the like.

[0019] 2, the glass base material 1 (glass substrate 10) has a flat plate shape with flat main surfaces 10A and 10B, but is not limited thereto and may have a curved plate shape. That is, the glass base material 1 (glass substrate 10) may have curved main surfaces 10A and 10B that are convex in the Z direction. When the main surfaces 10A and 10B of the glass base material 1 (glass substrate 10) are curved surfaces that are convex in the Z direction, the radius of curvature of the main surfaces 10A and 10B of the glass base material 1 (glass substrate 10) is preferably 10,000 mm or less, more preferably 5,000 mm or less, and even more preferably 3,000 mm or less. When the main surfaces 10A and 10B of the glass base material 1 (glass substrate 10) are curved and convex in the Z direction, the radius of curvature of the main surfaces 10A and 10B of the glass base material 1 (glass substrate 10) is preferably 10 mm or more, more preferably 50 mm or more, even more preferably 100 mm or more, and still more preferably 200 mm or more. In other words, when the main surfaces 10A and 10B of the glass base material 1 (glass substrate 10) are curved and convex in the Z direction, the radius of curvature of the main surfaces 10A and 10B of the glass base material 1 (glass substrate 10) is preferably 10 mm or more and 10,000 mm or less, more preferably 50 mm or more and 5,000 mm or less, even more preferably 100 mm or more and 3,000 mm or less, and still more preferably 200 mm or more and 3,000 mm or less.

[0020] The glass substrate 10 has a fracture toughness value K ＩＣ , 0.6 (MPa m ０．５ ) or more, and 0.6 (MPa m ０．５ ) or more 1.00 (MPa・m ０．５ ) or less, and more preferably 0.65 (MPa m ０．５ ) or more 0.70 (MPa・m ０．５ ) or less. ＩＣ can be measured by the Double Cleavage Drilled Compression (DCDC) method described in, for example, a non-patent document (NEW GASS Vol. 15 No. 2 2000 p. 18).

[0021] The glass substrate 10 may be amorphous glass or crystallized glass containing crystals on the surface or inside. Examples of glass substrates 10 that can be used include alkali-free glass, soda-lime glass, soda-lime silicate glass, aluminosilicate glass, borosilicate glass, lithium aluminosilicate glass, and borosilicate glass. The material of the glass substrate 10 is preferably alkali glass to ensure proper chemical strengthening. Furthermore, aluminosilicate glass or lithium aluminosilicate glass is preferred for the glass substrate 10, as these materials are susceptible to large stresses during tempering treatment even when thin, resulting in high-strength glass despite their thinness. Chemically strengthened glass based on aluminosilicate glass (e.g., "Dragontrail (registered trademark)" manufactured by AGC) is also suitable.

[0022] The glass substrate 10 contains, in mole percent on an oxide basis, SiO ２ 50% to 80%, Al ２ O ３ 1% to 20%, and Na ２ The glass substrate 10 may contain, in mole percent on an oxide basis, 50 to 80% of SiO2, 0.1 to 25% of Al2O3, 3 to 30% of Li2O+Na2O+K2O, 0 to 25% of MgO, 0 to 25% of CaO, and 0 to 5% of ZrO2. ... ２ 50% to 80%, Al ２ O ３ 1% to 20%, Na ２ O 6% to 20%, K ２ O 0% to 11%, MgO 0% to 15%, CaO 0% to 6%, and ZrO ２The glass substrate 10 may contain 0% to 5% of the above-mentioned elements. A numerical range expressed using "to" means a range that includes the numerical values ​​before and after "to" as the lower and upper limits. For example, 50% to 80% here means 50% or more and 80% or less, where the total mole percentage of the glass substrate 10 is 100%, and the same applies to other numerical ranges. For example, Li2O + Na2O + KO refers to the total content of Li2O, Na2O, and KO, and the same applies when "+" is used elsewhere.

[0023] More specifically, the following glass compositions are preferred for the glass substrate 10. For example, "containing 0% to 25% MgO" means that MgO is not essential but may be contained in an amount of up to 25%. Glass (i) is included in soda-lime silicate glass, glasses (ii) and (iii) are included in aluminosilicate glass, and glasses (iv) to (vi) are included in lithium aluminosilicate glass. (i) Glass with a composition expressed in mol %, containing 63% to 73% SiO, 0.1% to 5.2% AlO, 10% to 16% NaO, 0% to 1.5% KO, 0% to 5% LiO, 5% to 13% MgO, and 4% to 10% CaO. (ii) A glass having a composition expressed in mole percent containing 50% to 74% SiO, 1% to 10% AlO, 6% to 14% NaO, 3% to 11% KO, 0% to 5% LiO, 2% to 15% MgO, 0% to 6% CaO, and 0% to 5% ZrO, wherein the total content of SiO and AlO is 75% or less, the total content of NaO and KO is 12% to 25%, and the total content of MgO and CaO is 7% to 15%. (iii) Glass having a composition expressed in mole percent containing 68% to 80% SiO2, 4% to 10% Al2O3, 5% to 15% Na2O, 0% to 1% K2O, 0% to 5% Li2O, 4% to 15% MgO, and 0% to 1% ZrO2. (iv) Glass having a composition expressed in mole percent containing 67% to 75% SiO2, 0% to 4% Al2O3, 7% to 15% Na2O, 1% to 9% K2O, 0% to 5% Li2O, 6% to 14% MgO, and 0% to 1.5% ZrO2, with the total content of SiO2 and Al2O3 being 71% to 75%, the total content of Na2O and K2O being 12% to 20%, and the content of CaO, if any, being less than 1%. (v) A glass having a composition expressed in mol % of SiO2 56% to 73%, Al2O3 10% to 24%, B2O3 0% to 6%, P2O5 0% to 6%, Li2O 2% to 7%, Na2O 3% to 11%, K2O 0% to 5%, MgO 0% to 8%, CaO 0% to 2%, SrO 0% to 5%, BaO 0% to 5%, ZnO 0% to 5%, TiO2 0% to 2%, and ZrO2 0% to 4%. (vi) A glass having a composition expressed in mol % of SiO2 56% to 73%, Al2O3 10% to 24%, B2O3 0% to 6%, P2O5 0% to 6%, Li2O 2% to 7%, Na2O 3% to 11%, K2O 0% to 5%, MgO 0% to 8%, CaO 0% to 2%, SrO 0% to 5%, BaO 0% to 5%, ZnO 0% to 5%, TiO2 0% to 2%, and ZrO2 0% to 4%.２ 58% to 80%, Al ２ O ３ 13% to 18%, B ２ O ３ 0% to 5%, P ２ O ５ 0.5% to 4%, Li ２ 3% to 10% O, Na ２ O 5% to 20%, K ２ O 0% to 2%, MgO 0% to 11%, CaO 0% to 20%, SrO 0% to 20%, BaO 0% to 15%, ZnO 0% to 10%, TiO ２ 0% to 1%, ZrO ２ Glass containing 0% to 2% of

[0024] It is preferable that the glass substrate 10 is not chemically strengthened. Furthermore, it is preferable that neither the glass plate 20 obtained by cutting the glass substrate 10 nor the glass article 20T obtained by grinding the glass plate 20 is chemically strengthened. Since the glass substrate 10 is not chemically strengthened, chipping during cutting or chamfering can be suppressed. Therefore, the material (composition) of the glass plate 20 and the glass article 20T is the same as the material (composition) of the glass substrate 10. However, the glass article 20T after grinding may be chemically strengthened. The chemically strengthened glass article 20T is suitable for use as a cover glass for a display device. When the glass article 20T after grinding is chemically strengthened, the composition of the glass substrate 10 corresponds to the composition of the central portion in the plate thickness direction of the glass article 20T. Specifically, if the element that is substituted and released during chemical strengthening is defined as the pre-substitution element, and the element that is substituted and taken in during chemical strengthening is defined as the substitution element, then it can be said that the glass substrate 10 has a composition in which the pre-substitution element is included instead of the substitution element in the chemically strengthened surface layer of the glass article 20T.

[0025] (Setting of Virtual Line) In this manufacturing method, a virtual line R is set on the main surface of the prepared glass base material 1. In this embodiment, the virtual line R is set on the main surface 10A, but the virtual line may also be set on the opposite main surface 10B. The virtual line R is a line that indicates the trajectory of the laser light L irradiated onto the glass base material 1 (the trajectory of scanning of the irradiation position of the laser light L).

[0026] The perimeter of the virtual line R is 60 mm or more, preferably 80 mm or more and 2000 mm or less, more preferably 100 mm or more and 1000 mm or less, and even more preferably 254 mm or more and 769 mm or less. The perimeter of the virtual line R refers to the entire length of the virtual line R, and refers to the distance along the virtual line R from the start point of the virtual line R (start point P1 in the example of FIG. 3 described below) to the end point of the virtual line R (end point P3 in the example of FIG. 3). When viewed from the Z direction, the virtual line R has a shape having a closed curve or a shape having a concave locus. Hereinafter, a virtual line R having a shape having a closed curve will be described. A virtual line R having a shape having a concave locus will be described in Modification 2 described below.

[0027] A virtual line R having a shape with a closed curve means that at least a portion of the virtual line R is a closed curve. A closed curve refers to a line in which at least a portion of the section is curved and the start and end points of the line are at the same position. Here, the closed curve includes both a case in which the entire section is curved and a case in which only a portion of the section is curved and the other portions are straight. A virtual line R having a shape with a closed curve may be any shape in which at least a portion of the section is a closed curve. However, in this embodiment, it is preferable that at least a portion of the virtual line R is a closed curve and does not extend to the end surface 10C. By having the virtual line R have such a shape, the portion surrounded by the virtual line R can be cut out to appropriately form a glass plate 20 having an opening H, as described below. Note that the fact that the virtual line R does not extend to the end surface 10C can be rephrased as meaning that the entire section of the virtual line R is located inside the end surface 10C on the main surface 10A in the in-plane direction. The inward in-plane direction refers to the direction from the end face 10C toward the center of the main surface 10A when viewed from the Z direction, and the outward in-plane direction refers to the direction from the center of the main surface 10A toward the end face 10C when viewed from the Z direction.

[0028] FIG. 3 is a schematic diagram showing an example of a virtual line in this embodiment. In this embodiment, the virtual line R includes a second section R2, which is a closed curve. Preferably, the virtual line R includes a first section R1 in addition to the second section R2. The first section R1 is a section from the start point P1 of the virtual line R to the midpoint P2. The first section R1 is located more inward in the in-plane direction than the end face 10C on the main surface 10A throughout the entire section from the start point P1 to the midpoint P2. The second section R2 is a closed curve section connected to the first section R1. More specifically, the second section R2 is a section from the midpoint P2 to the end point P3, which is located at the same position as the midpoint P2, and the path from the midpoint P2 to the end point P3 is a closed curve surrounding the start point P1. The second section R2 is located more inward in the in-plane direction than the end face 10C on the main surface 10A throughout the entire section from the midpoint P2 to the end point P3. In the virtual line R having a closed curve, the second section R2 is a closed curve, for example, a section that forms the periphery of the target shape to be cut out, while the first section R1 is an arbitrary section that is provided separately from the closed curve, for example, set in an area that is not used as a product.

[0029] It is preferable that the first section R1 and the second section R2 are continuously connected. That is, it is preferable that the first section R1 and the second section R2 are smoothly connected at the midpoint P2, which is the boundary point between the first section R1 and the second section R2. In other words, it is preferable that the line passing through the first section R1 and the second section R2 is differentiable at the midpoint P2. In the example of FIG. 3 , when viewed from the Z direction, the second section R2 is a circle surrounding the starting point P1, and the first section R1 is a curve continuously connected to the second section R2. However, the shape of FIG. 3 is only an example, and the second section R2 is not limited to a circle and may be any closed curve surrounding the starting point P1. For example, the second section R2 may be an ellipse or a substantially polygonal shape with at least some curved vertices (e.g., a substantially rectangular shape with four curved vertices). By continuously connecting the first section R1 and the second section R2 in this manner, it is possible to prevent a large change in the scanning speed (movement speed) of the laser light L irradiation device M (described later) when switching from the first section R1 to the second section R2. This prevents the occurrence of residual thermal stress due to fluctuations in irradiation energy near the midpoint P2, suppresses chipping on the cut surface, and improves quality. However, the first section R1 and the second section R2 do not have to be continuous. For example, the first section R1 may be a discontinuous straight line connected to the second section R2.

[0030] In this embodiment, it is preferable to set an auxiliary virtual line RA in addition to the virtual line R. The auxiliary virtual line RA refers to the path along which the irradiation device M, described below, moves after the irradiation of the laser light L is stopped. The auxiliary virtual line RA is connected to the second section R2 and extends to a position different from the second section R2. That is, as shown in FIG. 3 , the auxiliary virtual line RA is a line connecting the end point P3 of the virtual line R to a point P4 located away from the end point P3. The point P4 may be set at any position different from the end point P3. For example, it may be in a position that does not overlap the virtual line R (second section R2), or it may be in a position that overlaps the virtual line R (second section R2). Furthermore, the point P4 may be located inside or outside the area enclosed by the second section R2. However, it is preferable that the auxiliary virtual line RA connecting the end point P3 to the point P4 be linear and continuously connected to the second section R2. Therefore, in this case, the point P4 is preferably located outside the area enclosed by the second section R2. By setting the preliminary virtual line RA in this manner, it is possible to provide a run-up section for the movement of the irradiation device M after the irradiation of the laser light L has stopped. This makes it possible to suppress the occurrence of residual thermal stress due to fluctuations in irradiation energy near the end point P3, suppress the occurrence of chipping on the cut surface, and improve quality.

[0031] In addition, in this embodiment, it is preferable not to set any auxiliary lines other than the virtual line R. The auxiliary line here refers to a path along which the laser light L is irradiated, which is provided discontinuously with respect to the virtual line R. That is, in this embodiment, it is preferable not to irradiate the glass base material 1 with the laser light L along a path other than the virtual line R. This prevents the laser light irradiation time from becoming excessive, and allows the manufacturing process to be carried out efficiently.

[0032] (Laser Light Irradiation) Figures 4 and 5 are schematic diagrams illustrating the irradiation of a glass base material with laser light, and Figure 6 is a schematic diagram of a glass plate. In this manufacturing method, as shown in Figure 4, the main surface 10A of the glass base material 1 is irradiated with laser light L along an imaginary line R. More specifically, in this embodiment, an irradiation device M that irradiates the laser light L is disposed at a position facing the main surface 10A of the glass base material 1, and the irradiation device M is moved relative to the glass base material 1 along the imaginary line R while irradiating the laser light L from the irradiation device M. As a result, the irradiation position of the laser light L is scanned along the imaginary line R (moved relative to the glass base material 1), and the laser light L is irradiated onto the main surface 10A. In this embodiment, the irradiation device M is moved relative to the glass base material 1, but the position of the laser head from which the laser light L is irradiated from the irradiation device M is fixed, and the glass base material 1 to which the laser light L is irradiated is moved, thereby moving the irradiation device M relative to the glass base material 1 (i.e., moving the irradiation position relative to the glass base material 1).

[0033] In the example of FIG. 4 , the laser beam L is irradiated from the starting point P1 to the intermediate point P2 while the irradiation position is scanned along the first section R1, and then from the intermediate point P2 to the end point P3 while the irradiation position is scanned along the second section R2. In the example of FIG. 4 , the irradiation of the laser beam L is stopped at the end point P3, and the irradiation device M moves relatively along the preliminary virtual line PA from a position opposite the end point P3 to a position opposite point P4. It is preferable that the irradiation position of the laser beam L is maintained at the starting point P1 for a predetermined period. That is, it is preferable that the laser beam L is irradiated at the starting point P1 for a predetermined period and then scanned along the virtual line R. The predetermined period here may be any length, for example, about 1 second. By continuing irradiation for a predetermined period while remaining at the starting point P1, the glass base material 1 can be properly cut.

[0034] The laser light L is a laser light in the infrared wavelength band having a wavelength of 9.1 μm or more and 10.8 μm or less. At this wavelength, the laser light L is absorbed by the glass base material 1, causing local melting in the glass base material 1 at the irradiated portion of the laser light L. By causing local melting, even in the case of a relatively thick plate having a thickness of 0.4 mm or more and a virtual line perimeter of 60 mm or more, or a shape with a large perimeter, a space is created between the glass base material and the portion surrounded by the virtual line, reducing friction and enabling successful separation. More preferably, when the wavelength of the laser light is 9.2 μm or more and 9.4 μm or less, the absorption coefficient of the glass base material 1 is larger, thereby improving the fusing speed at the same output. The laser light L is CO ２ CO using gas as a medium ２ It is preferable that the irradiation device M continuously irradiates the laser light L while moving the irradiation position of the laser light L. That is, the irradiation device M does not irradiate the laser light L in a pulsed manner in which irradiation and stopping of the laser light L is repeated while scanning, but irradiates the laser light L in a continuous manner in which irradiation of the laser light L is continued while scanning.

[0035] In this embodiment, it is preferable to irradiate the glass base material 1 with the laser beam L and inject the gas A from the injector Ma onto the location irradiated with the laser beam L. The injector Ma is provided at a position facing the main surface 10A of the glass base material 1 and injects the gas A onto the location of the main surface 10A irradiated with the laser beam L. This promotes the discharge of the portion of the glass base material 1 melted by the laser beam L by the gas A, thereby enabling the glass base material 1 to be properly melted along the imaginary line R. The gas A may be any gas, including air, nitrogen, and rare gases, and is preferably air. In the example of FIG. 5 , the injector Ma is attached to the irradiation device M and moves integrally with the irradiation device M to inject the gas A onto the location irradiated with the laser beam L. However, the location at which the injector Ma is provided is not limited thereto and may be any location.

[0036] By irradiating the glass base material 1 with the laser beam L in this manner, the glass base material 1 is fused (cut) along the imaginary line R, and the portion surrounded by the imaginary line R is cut out from the glass base material 1. In other words, by irradiating the laser beam L along the imaginary line R, a gap G is formed in the glass base material 1 along the imaginary line R, and the glass base material 1 is separated into a glass plate 30, which is the portion surrounded by the imaginary line R (gap G), and a glass plate 20, which is the portion other than the glass plate 30, thereby obtaining a glass plate 20 as shown in FIG. 6, for example. The glass plate 20 of this embodiment has a shape in which an opening H is formed in the portion where the glass plate 30 is cut out (the portion surrounded by the imaginary line R). Note that glass (a part of the glass base material 1) or molten glass may remain in the gap G. In this embodiment, the glass plate 20 is ground to produce a glass article 20T, which will be described later, but the glass article 20T may also be produced by grinding the glass plate 30. In this example, the glass base material 1 is composed of one glass substrate 10, and therefore the glass plate 20 and the glass plate 30 are also composed of one cut glass substrate 10. Hereinafter, the main surface of the glass plate 20 corresponding to the main surface 10A of the glass base material 1 will be referred to as the main surface 20A, and the main surface of the glass plate 20 corresponding to the main surface 10B of the glass base material 1 will be referred to as the main surface 20B.

[0037] (Damage Layer) A damage layer 20D is formed in the glass plate 20 by irradiation with laser light L. If the edge of the glass plate 20 along the imaginary line R formed by cutting with laser light L is defined as a cut surface 20C, the damage layer 20D can be said to be a layer formed from the cut surface 20C to a predetermined depth in the in-plane direction. Note that the glass plate 20 of this embodiment has a shape in which an opening H is formed in the portion where the glass plate 30 is cut out, and therefore the surface surrounding the opening H is the cut surface 20C. The damage layer 20D is a layer altered by irradiation with laser light L, and refers to a layer of the glass plate 20 whose refractive index has changed or a layer in which cracks have occurred. A layer whose refractive index has changed refers to a layer whose refractive index is different from that of the glass plate 20 other than the damage layer 20D due to the influence of at least one of composition, density, fictive temperature, and residual stress. Furthermore, the layer in which cracks have occurred refers to a layer in which the number of cracks per unit volume is greater than the number of cracks per unit volume at positions other than the damaged layer 20D of the glass plate 20. The damaged layer 20D can be measured using an optical observation device such as a microscope. For example, when the main surface 20A of the glass plate 20 is observed using a KEYENCE VHX6000, a region in which cracks or chips have occurred on the main surface 20A may be identified as the damaged layer 20D.

[0038] A damaged layer 30D is also formed on the cut surface 30C of the glass plate 30. The method for measuring the damaged layer 30D of the glass plate 30 is the same as the method for measuring the damaged layer 20D of the glass plate 20.

[0039] Here, the width of the damaged layer 20D is referred to as width D. Width D refers to the length (depth) of the damaged layer 20D in the in-plane direction. In other words, if the boundary surface between the damaged layer 20D and a portion of the glass plate 20 other than the damaged layer 20D is referred to as boundary surface 20D1, width D refers to the distance in the in-plane direction (X direction in the example of FIG. 5 ) from the cut surface 20C to boundary surface 20D1. Width D can be measured by identifying the damaged layer 20D as described above. The width D (μm) of the damaged layer 20D satisfies the following formula (1), and more preferably formula (2). Note that t in formulas (1) and (2) refers to the thickness t (μm) of the glass substrate 10, and can also be said to be the thickness of a single glass substrate 10 cut along the virtual line R of the glass plate 20.

[0040] 0.2・t≦D≦2000μm...(1) 0.2・t+100μm≦D≦2000μm...(2)

[0041] As shown in formulas (1) and (2), the width D is preferably 0.2 times the thickness t or more and 2000 μm or less, and more preferably 0.2 times the thickness t + 100 μm or more and 2000 μm or less. By irradiating the laser beam L so that the lower limit of the width D is within this range, the glass base material 1 can be sufficiently melted by the laser beam L and appropriately cut. By irradiating the laser beam L so that the upper limit of the width D of the damaged layer 20D is within this range, the thickness to be ground at the end face can be reduced when removing the damaged layer 20D by grinding in a subsequent process, and the grinding volume per unit area of ​​the end face can be reduced, thereby suppressing the occurrence of chipping. The width D of the damaged layer 30D of the glass plate 30 also preferably satisfies formula (1), and more preferably satisfies formula (2).

[0042] (Cutting Conditions) In this manufacturing method, the width D can be set within the above range by adjusting the cutting conditions of the glass base material 1. The cutting conditions include at least one of the output of the laser light L, the irradiation diameter (spot diameter) of the laser light L, the scanning speed of the laser light L (the moving speed of the irradiation position of the laser light L), and the flow rate of the gas A (the flow rate of the gas A injected per unit time), and it is preferable that all of these are used. For example, the width D increases as the output of the laser light L increases, the width D increases as the irradiation diameter of the laser light L increases, the width D increases as the scanning speed of the laser light L decreases, and the width D increases as the flow rate of the gas A decreases.

[0043] The output of the laser light L is preferably 10 W or more and 10,000 W or less, more preferably 30 W or more and 7,000 W or less, and even more preferably 50 W or more and 4,000 W or less. The irradiation diameter of the laser light L is preferably 0.0005 mm or more and 3 mm or less, more preferably 0.001 mm or more and 2 mm or less, and even more preferably 0.01 mm or more and 1 mm or less. The scanning speed of the laser light L is preferably 6 mm / min or more and 3,600 mm / min or less, more preferably 60 mm / min or more and 2,400 mm / min or less, and even more preferably 200 mm / min or more and 1,200 mm / min or less. The flow rate of the gas A is preferably 10 L / min or more and 900 L / min or less, more preferably 30 L / min or more and 700 L / min or less, and even more preferably 50 L / min or more and 500 L / min or less. By setting the cutting conditions within the above ranges, the width D can be kept within an appropriate range, and the glass base material 1 can be cut appropriately while suppressing deterioration in quality.

[0044] (Grinding) FIG. 7 is a schematic diagram illustrating grinding of a glass plate, and FIG. 8 is a schematic diagram of a glass article. In this manufacturing method, as shown in FIG. 7, the cut surface 20C of the glass plate 20 is ground with a grindstone W to obtain a glass article 20T. More specifically, by grinding the cut surface 20C of the glass plate 20 with the grindstone W, the damaged layer 20D is removed, and the glass plate 20 from which the damaged layer 20D has been removed is obtained as the glass article 20T. That is, as shown in FIG. 8, the glass article 20T can be said to be a glass plate having a main surface 20A, a main surface 20B, and a ground surface 20E formed by grinding. In this embodiment, the surface surrounding the opening H of the glass article 20T is the ground surface 20E.

[0045] The ground surface 20E of the glass article 20T may have any shape, but in this embodiment, it includes a side portion 20E1 and a chamfered portion 20E2. The side portion 20E1 may be flat or curved. The chamfered portion 20E2 is formed between the side portion 20E1 and the main surface (main surface 20A or 20B) in the Z direction and is a chamfered surface connecting the side portion 20E1 and the main surface. The chamfered portion 20E2 is inclined with respect to both the side portion 20E1 and the main surface (main surface 10A or 10B) when viewed from a direction perpendicular to the Z direction (the Y direction in the example of FIG. 7). The chamfered portion 20E2 may be flat (i.e., C-chamfered) or curved (R-chamfered). In this embodiment, the grinding surface 20E includes, as the chamfered portion 20E2, a chamfered portion 20E2 connecting the side surface portion 20E1 and the main surface 20A, and a chamfered portion 20E2 connecting the side surface portion 20E1 and the main surface 20B. However, the grinding surface 20E may include only one of the chamfered portion 20E2 connecting the side surface portion 20E1 and the main surface 20A and the chamfered portion 20E2 connecting the side surface portion 20E1 and the main surface 20B.

[0046] Any method for grinding the cut surface 20C using the grinding wheel W may be used. For example, the grinding wheel W is rotated around a central axis along the axial direction of the grinding wheel W as a rotation axis, and the grinding surface WA (the surface on which abrasive grains are provided) of the grinding wheel W is pressed against the cut surface 20C while the grinding wheel W is moved relative to the glass plate 20 along the cut surface 20C. This grinds the cut surface 20C, forming a ground surface 20E. The feed speed of the grinding wheel W (the relative movement speed of the grinding wheel W with respect to the glass plate 20) may be any speed, but is preferably 200 mm / min to 3000 mm / min, more preferably 200 mm / min to 2000 mm / min, and even more preferably 200 mm / min to 1000 mm / min. This allows the cut surface 20C to be properly ground. It is desirable for the grinding wheel to rotate in an up-cut direction. This makes it easier to remove the molten glass produced during cutting and the intermediate layer 40 in the case of laminated glass that adheres to the laser cut surface, and also improves the quality of the end surface after grinding.

[0047] Any material may be used for the abrasive grains provided on the grinding wheel W. Examples of the material for the abrasive grains include single crystal diamond, cubic boron nitride, silicon carbide, and alumina, with single crystal diamond being preferred.

[0048] The shape of the grinding wheel W is not particularly limited and may be cylindrical, spherical, or the like. However, a formed grinding wheel having a first portion WA1 and a second portion WA2 on the grinding surface WA is preferred. A formed grinding wheel is a grinding wheel having a grinding surface that matches the shape of the target workpiece. The first portion WA1 has a grinding surface corresponding to the side portion 20E1, in other words, a grinding surface for forming the side portion 20E1. The first portion WA1 is cylindrical, and its outer peripheral surface forms the grinding surface. The second portion WA2 has a grinding surface corresponding to the chamfered portion 20E2, in other words, a grinding surface for forming the chamfered portion 20E2. The second portion WA2 is connected axially to the first portion WA1 and has a cone shape whose diameter increases as it moves away from the first portion WA1, and its outer peripheral surface forms the grinding surface. In this embodiment, the grinding wheel W has a second portion WA2 provided on one axial side of the first portion WA1 and a second portion WA2 provided on the other axial side of the first portion WA1. The width of the chamfered portion is, for example, 0.05 mm or more and 0.5 mm or less, preferably 0.1 mm or more and 0.3 mm or less. The boundary between the grinding surface (outer peripheral surface) of the first portion WA1 and the grinding surface (outer peripheral surface) of the second portion WA2 is preferably rounded (curved). The radius of curvature of this boundary is preferably 0.05 mm or more, more preferably 0.1 mm or more and 0.5 mm or less, and even more preferably 0.2 mm or more and 0.3 mm or less. By having the radius of curvature of the boundary within this range, the radius of curvature of the boundary between the side portion 20E1 and the chamfered portion 20E2 obtained by grinding can also be within this range, thereby more suitably reducing chipping.

[0049] In this embodiment, grinding is preferably performed using multiple grinding wheels with different median diameters D50. Specifically, in this embodiment, it is preferable to grind the cut surface 20C of the glass plate 20 with a first grinding wheel, and then grind the cut surface 20C (the surface ground with the first grinding wheel) with a second grinding wheel. The first grinding wheel is a grinding wheel having abrasive grains with a median diameter D50 of 30 μm to 50 μm, in other words, a grinding member having a plurality of abrasive grains with a median diameter D50 of 30 μm to 50 μm provided on its surface. The second grinding wheel is a grinding wheel having abrasive grains with a smaller median diameter D50 than the first grinding wheel. The second grinding wheel is preferably a grinding wheel having abrasive grains with a median diameter D50 of 10 μm to 25 μm, in other words, a grinding member having a plurality of abrasive grains with a median diameter D50 of 10 μm to 25 μm provided on its surface. By using such a grinding stone for grinding, the damaged layer 20D can be removed while suppressing the occurrence of chipping, thereby appropriately improving the quality. The median diameter D50 of the abrasive grains can be measured by a particle size distribution analyzer.

[0050] (Effects) As described above, in the manufacturing method according to this embodiment, the glass base material 1 is cut by irradiating it with laser light L so that the width D of the damaged layer 20D satisfies formula (1). Then, the cut surface 20C of the glass plate 20 obtained by cutting is ground to remove the damaged layer 20D, thereby obtaining a glass article 20T. When cutting the glass base material 1 along a virtual line R having a large thickness t of 0.4 mm or more and a long perimeter of 60 mm or more, it is necessary to efficiently obtain a glass article 20T having a desired shape while suppressing deterioration of the quality of the cut surface, such as chipping. In contrast, according to this embodiment, the glass base material 1 is cut using laser light L having a wavelength within the above range so that the width D of the damaged layer 20D falls within the above range. This allows the glass base material 1 to be cut appropriately while suppressing deterioration of the quality of the ground surface 20E, such as chipping. Furthermore, by not making the width D of the damaged layer 20D too large, the grinding time with the grindstone W for removing the damaged layer 20D can be shortened, and the glass article 20T of the desired shape can be obtained efficiently.

[0051] (Modifications) Next, modifications of the first embodiment will be described. In the following modifications, the description of parts that are common to the first embodiment will be omitted.

[0052] 9 is a schematic diagram showing a virtual line according to Modification 1. The virtual line R in this example has a shape that has a closed curve, similar to that of the first embodiment, but is different in shape from the virtual line R in the first embodiment. Specifically, the target shape of the cutout in this example is the same as that of the first embodiment, but differs from that of the first embodiment in that the position of the virtual line R is shifted relative to the target shape.

[0053] 9 , the virtual line R in this example includes a first section R1 and a second section R2 connected to the first section R1. The first section R1 in this example is a section from a start point P1 of the virtual line R to a midpoint P2 of the virtual line R. The second section R2 in this example is a section that extends from the midpoint P2, passing through midpoints P2A and P2B, to an end point P3 that is located at the same position as the midpoint P2. The trajectory that runs from the midpoint P2, passing through the midpoints P2A and P2B, and returning to the end point P3 forms a closed curve that surrounds the start point P1.

[0054] The midpoint P2A is located farther from the starting point P1 than the midpoint P2 (in the example of FIG. 9 , closer to the X1 direction than the midpoint P2) and is offset in the Y direction from the midpoint P2 (in the example of FIG. 9 , closer to the Y2 direction than the midpoint P2). The midpoint P2B is located farther from the starting point P1 than the midpoint P2 (in the example of FIG. 9 , closer to the X1 direction than the midpoint P2) and is offset in the Y direction from the midpoint P2 (in the example of FIG. 9 , closer to the Y1 direction than the midpoint P2). In other words, if the shortest line that connects the midpoint P2B and the midpoint P2A and that continues into the section R2b from the midpoint P2A to the midpoint P2B in the second section R2 is defined as the perimeter line LI, the midpoint P2 is located closer to the starting point P1 than the perimeter line LI (in the example of FIG. 9 , closer to the X2 direction than the midpoint P2). In other words, the midpoint P2 is located at a position surrounded by a closed curve that includes the section R2b and the outer periphery line LI. The distance ΔR between the midpoint P2 and the outer periphery line LI is, for example, preferably 3 mm or less, more preferably 0.2 mm or more and 2.5 mm or less, and even more preferably 0.5 mm or more and 1 mm or less.

[0055] Furthermore, section R2a of second section R2, which is the section from midpoint P2 to midpoint P2A, is continuously connected to section R2b at midpoint P2A. Similarly, section R2c of second section R2, which is the section from midpoint P2B to midpoint P2, is continuously connected to section R2b at midpoint P2B.

[0056] In this example, as in the first embodiment, laser light L is irradiated along the imaginary line R to separate the glass base material 1 into a glass plate 30 surrounded by the imaginary line R and a glass plate 20 in which the portion surrounded by the imaginary line R becomes an opening H. In this example, the glass plate 20 has a protruding shape at the portion surrounded by the outer periphery line LI and the sections R2a and R2c (protruding portion 20X), and it is preferable to remove the protruding portion 20X by grinding to produce the glass article 20T.

[0057] Here, residual thermal stress tends to remain large near the end point P3 (midpoint P2). In contrast, by setting the virtual line R as in this example, a protruding portion 20X can be left near the end point P3, and the protruding portion 20X can be removed by grinding. That is, in this example, the grinding allowance near the end point P3 can be increased by the amount of the protruding portion 20X removed. Therefore, according to this example, the portion with large residual thermal stress can be reliably removed by grinding, the occurrence of chipping can be suitably suppressed, and quality can be improved.

[0058] (Modification 2) Fig. 10 is a schematic diagram showing a virtual line according to Modification 2, and Fig. 11 is a schematic diagram of a glass article according to Modification 2. Unlike the first embodiment, the virtual line R in this example does not have a shape with a closed curve, but has a shape with a concave locus.

[0059] A virtual line R having a shape with a concave locus refers to a shape in which the starting point P1 and the ending point P3 of the virtual line R are located on the end face of the glass base material 1 (end face 10C of the glass substrate 10), and in at least a portion of the section, the virtual line R has a locus (concave locus) that is recessed inward in the in-plane direction on the main surface 10A of the glass base material 1.

[0060] Specifically, the virtual line R of this example has a first section R1, a second section R2, and a third section R3, as shown in Fig. 10. The perimeter of the virtual line R of this example is also the same as the perimeter of the virtual line R of the first embodiment.

[0061] The first section R1 is a section from the start point P1 of the virtual line R to the midpoint P2A of the virtual line R. The start point P1 is located at a position on the main surface 10A where it connects to the end surface 10C (a position overlapping with the end surface 10C when viewed from the Z direction), and the midpoint P2A is located inside the end surface 10C when viewed from the Z direction. In the example of FIG. 10 , the start point P1 is located on the side of the main surface 10A on the X2 direction side, and the midpoint P2A is located closer to the X1 direction than the start point P1. Therefore, in the example of FIG. 10 , the first section R1 extends from the start point P1 to the midpoint P2A in the X1 direction.

[0062] The second section R2 is a section from midpoint P2A to midpoint P2D, and the trajectory from midpoint P2A to midpoint P2D is a concave trajectory that concaves inward in the in-plane direction (concave toward direction Y1 in the example of FIG. 10 ). In the example of FIG. 10 , the second section R2 includes sections R2A, R2B, and R2C. Section R2A is a section from midpoint P2A to midpoint P2B that heads inward in the in-plane direction (toward direction Y1 in the example of FIG. 10 ). Section R2B is a section from midpoint P2B to midpoint P2C that heads in a direction intersecting section R2A (toward direction X1 in the example of FIG. 10 ). Section R2C is a section from midpoint P2C to midpoint P2D that heads outward in the in-plane direction (toward direction Y2 in the example of FIG. 10 ). However, the shape of the second section R2 is not limited to the example shown in FIG. 10, and may be any shape recessed inward in the in-plane direction.

[0063] The third section R3 is a section from the midpoint P2D to the end point P3 of the virtual line R. The end point P3 is located at a position on the main surface 10A where it connects to the end surface 10C (a position overlapping with the end surface 10C when viewed from the Z direction). In the example of Fig. 10 , the end point P3 is located on the side of the main surface 10A on the X1 direction side, and the third section R3 extends from the midpoint P2D to the end point P3 in the X1 direction.

[0064] 10 is an example, and the start point P1 and the end point P3 are not limited to being located on the side of the main surface 10A on the X1-X2 direction side. For example, the start point P1 and the end point P3 may be located on the side of the main surface 10A on the Y2 direction side. In this case, the first section R1 extends from the start point P1 to the midpoint P2A toward the Y1 direction side, and the third section R3 extends from the midpoint P2D to the end point P3 toward the Y2 direction side.

[0065] In this example, as in the first embodiment, laser light L is irradiated along the imaginary line R to separate the portion of the glass base material 1 surrounded by the imaginary line R. That is, in this example, the glass base material 1 is separated into a glass plate 20 and a glass plate 30 along the imaginary line R. The glass plate 30 is the portion of the glass base material 1 separated along the imaginary line R surrounded by the imaginary line R (the portion surrounded by the imaginary line R and the end face 10C of the glass base material 1 on the direction Y2 side). The glass plate 20 is the portion of the glass base material 1 separated along the imaginary line R other than the glass plate 30, and is the portion in which a recess Ha recessed inward in the in-plane direction is formed by the recess locus of the imaginary line R. That is, in this example, the end face forming the recess Ha of the glass plate 20 becomes the cut surface 20C.

[0066] As in the first embodiment, in this example, a damaged layer 20D is formed on the cut surface 20C of the glass plate 20 by irradiation with laser light L. In this example, the cut surface 20C of the glass plate 20 is also ground with a grinding wheel W to remove the damaged layer 20D formed on the cut surface 20C, thereby obtaining a glass article 20T. That is, as shown in Fig. 11 , the glass article 20T according to this example has a shape in which a recess Ha is formed on the side on the direction Y2 side, and the end surface forming the recess Ha can be said to be a ground surface 20E.

[0067] Even when cutting along a virtual line R having a concave trajectory, as in this example, by irradiating laser light L so that the width D of the damaged layer 20D is within the above range, the glass base material 1 can be cut appropriately, and a glass article 20T of the desired shape can be efficiently obtained while suppressing deterioration in the quality of the grinding surface 20E.

[0068] Second Embodiment Next, a second embodiment will be described. The second embodiment differs from the first embodiment in that a laminated glass having a plurality of glass substrates 10 is used as the glass base material 1. In the second embodiment, a description of parts that are common to the first embodiment will be omitted. Note that the second embodiment can also be applied to each modified example of the first embodiment.

[0069] (Glass Base Material) The glass base material 1 is, for example, a window component for a vehicle. FIG. 12 is a schematic cross-sectional view of a glass base material according to a second embodiment. As shown in FIG. 12 , the glass base material 1 according to the second embodiment is a laminated glass including a first glass base 12 as a glass substrate 10, a second glass base 14 as a glass substrate 10, and an intermediate layer 40 provided between the first glass base 12 and the second glass base 14 in the Z direction. The glass base material 1 is laminated in the Z2 direction in the order of the first glass base 12, the intermediate layer 40, and the second glass base 14. Therefore, in this embodiment, the main surface 12A of the first glass base 12 on the Z1 direction side becomes the main surface 10A of the glass base material 1, and the main surface 14B of the second glass base 14 on the Z2 direction side becomes the main surface 10B of the glass base material 1. Furthermore, the main surface 12B of the first glass substrate 12 on the Z2 side can be said to be the main surface of the first glass substrate 12 on the intermediate layer 40 side, and the main surface 14A of the second glass substrate 14 on the Z1 side can be said to be the main surface of the second glass substrate 14 on the intermediate layer 40 side.

[0070] When the glass base material 1 is a window member for a vehicle, the first glass substrate 12 may be the glass substrate 10 on the vehicle exterior side, and the second glass substrate 14 may be the glass substrate 10 on the vehicle interior side. That is, in this case, the main surface 12A (main surface 10A) of the first glass substrate 12 is the surface facing the vehicle exterior side, and the main surface 14B (main surface 10B) of the second glass substrate 14 is the surface facing the vehicle interior side.

[0071] The glass base material 1 according to the second embodiment is a laminated glass having two glass substrates 10, a first glass substrate 12 and a second glass substrate 14, but the number of glass substrates 10 is not limited to this and may be three or more.

[0072] Here, the thickness of the glass substrate 10 is referred to as thickness t. When the glass base material 1 is made of a single glass substrate 10, thickness t refers to the thickness of the glass base material 1 itself. When the glass base material 1 includes a plurality of glass substrates 10, thickness t refers to the thickness of a single glass substrate 10. The thickness t of the glass base 10 is 0.4 mm or more, preferably 1 mm or more and 5.0 mm or less, and more preferably 1.5 mm or more and 3.0 mm or less. Note that thickness t refers to the length in the Z direction from the main surface 10A to the main surface 10B.

[0073] In the example of Fig. 12, the glass base material 1 (glass substrate 10) has a flat plate shape with flat principal surfaces 10A and 10B, but is not limited thereto and may have a curved plate shape. That is, the glass base material 1 (glass substrate 10) may have a curved surface shape with the principal surfaces 10A and 10B convex in the Z direction, or a curved surface shape with the principal surfaces 10A and 10B convex in the Z1 direction (i.e., a shape convex toward the vehicle exterior). When the principal surfaces 10A and 10B of the glass base material 1 (glass substrate 10) have a curved surface shape with the principal surfaces 10A and 10B convex in the Z direction, the radius of curvature of the principal surfaces 10A and 10B of the glass base material 1 (glass substrate 10) is preferably 300,000 mm or less, more preferably 50,000 mm or less, and even more preferably 30,000 mm or less. When the main surfaces 10A and 10B of the glass base material 1 (glass substrate 10) are curved and convex in the Z direction, the radius of curvature of the main surfaces 10A and 10B of the glass base material 1 (glass substrate 10) is preferably 10 mm or more, more preferably 50 mm or more, even more preferably 100 mm or more, and still more preferably 200 mm or more. In other words, when the main surfaces 10A and 10B of the glass base material 1 (glass substrate 10) are curved and convex in the Z direction, the radius of curvature of the main surfaces 10A and 10B of the glass base material 1 (glass substrate 10) is preferably 10 mm or more and 300,000 mm or less, more preferably 50 mm or more and 50,000 mm or less, even more preferably 100 mm or more and 30,000 mm or less, and still more preferably 200 mm or more and 20,000 mm or less.

[0074] When the glass base material 1 is a window member for a vehicle, the glass base material 1 may be made of, for example, soda lime glass, borosilicate glass, aluminosilicate glass, or the like.

[0075] The intermediate layer 40 is a film that bonds the first glass substrate 12 and the second glass substrate 14. Thermoplastic resins are often used for the intermediate layer 40, and examples thereof include thermoplastic resins that have traditionally been used for this type of purpose, such as plasticized polyvinyl acetal resins, plasticized polyvinyl chloride resins, saturated polyester resins, plasticized saturated polyester resins, polyurethane resins, plasticized polyurethane resins, ethylene-vinyl acetate copolymer resins, ethylene-ethyl acrylate copolymer resins, cycloolefin polymer resins, and ionomer resins.

[0076] The glass base material 1 may also have a functional layer 50. The functional layer 50 is a component that imparts additional functions to the glass base material 1. The functional layer 50 includes, for example, at least one of a heating layer, a dimming layer, a light-emitting display layer, and a solar cell layer, and is more preferably a heating layer. The heating layer is a film that generates heat when electricity is applied. The dimming layer is a film that can adjust the transmittance of visible light in response to input. The light-emitting display layer is a film configured by arranging pixels made of light-emitting elements, and can display an image by applying electricity to each pixel. The light-emitting elements include organic or inorganic EL (electroluminescence) elements. The solar cell layer is a solar cell that converts light energy into electricity, formed into a film.

[0077] The functional layer 50 is located between the first glass substrate 12 and the second glass substrate 14 in the Z direction (between the first glass substrate 12 and the intermediate layer 40 in the example of Figure 12), but it may be located at any position, for example, on the main surface 12A of the first glass substrate 12 or on the main surface 14B of the second glass substrate 14.

[0078] The glass base material 1 may also have a shielding layer 60. The shielding layer 60 is an opaque layer. The shielding layer 60 is, for example, an opaque (e.g., black) colored ceramic layer. The shielding layer 60 may be a colored interlayer or film having light-shielding properties, or a combination of a colored interlayer and a colored ceramic layer. The colored film may be integrated with an infrared reflective film or the like.

[0079] The shielding layer 60 can be formed, for example, by applying a ceramic color paste containing a fusible glass frit containing a black pigment onto a glass plate by screen printing or the like, and then firing the paste, but is not limited to this. The shielding layer 60 may also be formed, for example, by applying an organic ink containing a black or dark color pigment onto a glass plate by screen printing or the like, and then drying the ink.

[0080] The shielding layer 60 is provided in a strip shape along the peripheral edge of the glass base material 1 when viewed from the Z direction. The glass base material 1 blocks visible light in an area overlapping with the shielding layer 60 in the Z direction, and transmits visible light in an area not overlapping with the shielding layer 60 in the Z direction (an area surrounded by the shielding layer 60). The shielding layer 60 is located on the main surface 14B of the second glass base 14, but the position at which the shielding layer 60 is provided in the Z direction is arbitrary, and may be located, for example, on the main surface 12A of the first glass base 12 or between the first glass base 12 and the second glass base 14 in the Z direction.

[0081] (Glass Plate) FIG. 13 is a schematic cross-sectional view of a glass plate in the second embodiment. In the second embodiment, as in the first embodiment, an imaginary line R is set on a main surface (e.g., main surface 10A) of the glass base material 1, and laser light L is irradiated along the imaginary line R to cut the glass base material 1 and obtain a glass plate 20. In the present embodiment, as in the first embodiment, an imaginary line R having a closed curve is set, and a portion surrounded by the imaginary line R is separated from the glass base material 1 by irradiation with laser light L to obtain a glass plate 20. In the present embodiment, the laser light L is irradiated to cut each layer of the glass base material 1 that overlaps with the imaginary line R when viewed from the Z direction (in the example of FIG. 13 , the first glass base 12, the functional layer 50, the intermediate layer 40, the second glass base 14, and the shielding layer 60) along the imaginary line R to produce the glass plate 20. That is, the glass plate 20 of the present embodiment can be said to be a laminated glass having the first glass substrate 12, the intermediate layer 40, and the second glass substrate 14 cut by irradiation with laser light L (in the example of FIG. 13 , it is a laminated glass having the first glass substrate 12, the functional layer 50, the intermediate layer 40, the second glass substrate 14, and the shielding layer 60 cut by irradiation with laser light L). Hereinafter, in the glass plate 20, the first glass substrate 12 cut by irradiation with laser light L will be referred to as a first glass plate 12a, and the second glass substrate 14 cut by irradiation with laser light L will be referred to as a second glass plate 14a.

[0082] In this embodiment, the glass base material 1 is cut along an imaginary line R having a closed curve, as in the first embodiment. Therefore, the glass plate 20 has a shape in which an opening H is formed in a portion surrounded by the imaginary line R. The end surface surrounding the opening H of the glass plate 20 can be considered to be a cut surface 20C. That is, in this embodiment, by cutting by irradiating the laser light L, an opening 12H is formed in the first glass plate 12a, an opening 40H is formed in the intermediate layer 40, an opening 14H is formed in the second glass plate 14a, an opening 50H is formed in the functional layer 50, and an opening 60H is formed in the shielding layer 60. In this embodiment, the opening H can be considered to be formed by the opening 12H in the first glass plate 12a, the opening 40H in the intermediate layer 40, and the opening 14H in the second glass plate 14a (in the example of FIG. 13 , the opening 12H, the opening 50H, the opening 40H, the opening 14H, and the opening 60H in the shielding layer 60).

[0083] In this embodiment, when viewed from the Z direction, opening 12H, opening 40H, and opening 14H (in the example of FIG. 13, opening 12H, opening 50H, opening 40H, opening 14H, and opening 60H) overlap, in other words, these openings are in communication with each other. It can be said that opening H in this embodiment is formed by these openings being in communication with each other in the Z direction.

[0084] In this embodiment as well, a damaged layer 20D is formed on the cut surface 20C of the glass plate 20 (the cut surface of the first glass substrate 12 and the second glass substrate 14).

[0085] (Glass Article) FIG. 14 is a schematic top view of a glass article according to the second embodiment. In this embodiment, too, the cut surfaces 20C of each layer of the glass plate 20 are ground with a grinding wheel W to remove the damaged layer 20D, thereby obtaining a glass article 20T. That is, as shown in FIGS. 13 and 14 , the glass article 20T according to this embodiment has a shape in which an opening H is formed. As shown in FIG. 13 , the end surface surrounding the opening H of the glass article 20T can be referred to as the ground surface 20E. Hereinafter, the first glass plate 12a in the glass article 20T from which the damaged layer 20D has been removed by grinding will be referred to as the first glass article 12b, and the second glass plate 14a from which the damaged layer 20D has been removed by grinding will be referred to as the second glass article 14b. Note that the glass article 20T (the first glass article 12b and the second glass article 14b) may be flat, as in the first embodiment, or may have a curved surface that is convex in direction Z1 (i.e., a shape that is convex toward the vehicle exterior).

[0086] (Aperture) Here, aperture 12H of first glass article 12b after the cut surface (outer peripheral surface of aperture 12H) has been ground is referred to as aperture 12HT. Furthermore, aperture 14H of second glass article 14b after the cut surface (outer peripheral surface of aperture 14H) has been ground is referred to as aperture 14HT. Furthermore, aperture 40H of intermediate layer 40 after the cut surface (outer peripheral surface of aperture 40H) has been ground is referred to as aperture 40HT. Furthermore, aperture 50H of functional layer 50 after the cut surface (outer peripheral surface of aperture 50H) has been ground is referred to as aperture 50HT. Furthermore, aperture 60H of shielding layer 60 after the cut surface (outer peripheral surface of aperture 60H) has been ground is referred to as aperture 60HT. In this case, the opening H of the glass article 20T can be said to be composed of the opening 12HT, the opening 40HT, and the opening 14HT (in the example of Figure 13, the opening 12HT, the opening 50HT, the opening 40HT, the opening 14HT, and the opening 60HT).

[0087] In this embodiment, when viewed from the Z direction, openings 12HT, 40HT, and 14HT (in the example of FIG. 13 , openings 12HT, 50HT, 40HT, 14HT, and 60HT) overlap, in other words, these openings are in communication with one another. It can be said that opening H in glass article 20T is formed by these openings being in communication with one another in the Z direction.

[0088] These openings (Opening H, Opening 12HT, Opening 50HT, Opening 40HT, Opening 14HT, and Opening 60HT) are formed by cutting along the imaginary line R. Therefore, the perimeter of these openings, like the perimeter of the imaginary line R, is 60 mm or more, preferably 80 mm or more to 2000 mm or less, and more preferably 100 mm or more to 1000 mm or less. Here, the perimeter of the opening refers to the total length of the periphery of the opening when viewed from the Z direction. Furthermore, when viewed from the Z direction, the minimum radius of curvature of the periphery of these openings (Opening H, Opening 12HT, Opening 50HT, Opening 40HT, Opening 14HT, and Opening 60HT) is preferably 5 mm or more, preferably 7 mm or more to 200 mm or less, and more preferably 10 mm or more to 100 mm or less. By setting the size and shape of the openings in this manner, a member can be appropriately inserted into the opening. Any member may be inserted into the opening, but it may be a transparent member that transmits infrared light. Any material may be used as the transparent member, but for example, a material that transmits far infrared rays is preferred, and it is preferable that the material has a base material whose main component is at least one selected from the group consisting of silicon (Si), germanium (Ge), zinc sulfide (ZnS), zinc selenide (ZnSe), and chalcogenide glass.

[0089] Furthermore, for these openings (Aperture H, Aperture 12HT, Aperture 50HT, Aperture 40HT, Aperture 14HT, and Aperture 60HT), the distance between the inscribed circle of the opening and the end of the opening is preferably 1 mm or more. The end of the opening here refers to the point on the entire circumference of the opening that is farthest from the inscribed circle of the opening when viewed from the axial direction of the opening (the Z direction in this example). In other words, this means that the shape of the opening is not a perfect circle, but rather a shape (e.g., ellipse or rectangle) in which the width in one direction of the opening is longer than the width in other directions. By configuring the opening in this shape, the FOV (Field of View) of the sensor can be expanded in the major axis direction (the direction in which the width is longer), thereby enabling detection by the sensor to be performed effectively.

[0090] Furthermore, in the present embodiment, one opening H is formed in the glass article 20T, but the number of openings H formed in the glass article 20T is arbitrary, and two or more openings H may be formed. That is, for example, a plurality of openings 12HT may be formed in the first glass base 12, and a plurality of openings 14HT may be formed in the second glass base 14.

[0091] (Amount of misalignment of openings) When viewed from the Z direction, the amount of misalignment between the end faces of openings 12HT and 14HT is 100 μm or less, more preferably 70 μm or less, and even more preferably 50 μm or less. With the amount of misalignment of the end faces within this range, the misalignment between the openings when viewed from the Z direction is small, thereby suppressing dimensional quality degradation. For example, the small misalignment between the openings allows a member, for example, to be properly inserted into opening H. Here, the amount of misalignment of the end faces refers to the distance between a predetermined point on the periphery of one opening (here, opening 12HT) and a predetermined point on the periphery of the other opening (here, opening 14HT) when viewed from the Z direction. The predetermined points here refer to points on the peripheries of the openings that have the same relative position relative to the center of the openings. That is, for example, if the predetermined point of opening 12HT is a point on the periphery in the direction X1 relative to the center of opening 12HT, the predetermined point of opening 14HT is a point on the periphery in the direction X1 relative to the center of opening 14HT. The amount of deviation of the end faces may also refer to the distance between the center point of one opening and the center point of the other opening.

[0092] While the above description has been given regarding the amount of misalignment between the end face of opening 12HT and the end face of opening 40HT, it is preferable that the amount of misalignment between the end faces of the other two openings also be within the above range. That is, for example, it is preferable that the amount of misalignment between the end face of opening 12HT and the end face of opening 40HT, and the amount of misalignment between the end face of opening 14HT and the end face of opening 40HT also be within the above range. In this embodiment, laser light L is irradiated onto the laminated glass to form openings in each layer at once, thereby reducing the amount of misalignment between the openings. Furthermore, in this embodiment, the outer peripheral surfaces of the openings in each layer are ground simultaneously, thereby reducing the amount of misalignment between the openings. This allows a member to be properly inserted into opening H.

[0093] (Inclination angle of openings) In the example of Figure 13, the end faces (ground surfaces) of these openings (opening H, opening 12HT, opening 50HT, opening 40HT, opening 14HT, and opening 60HT) are aligned along the normal AX of the main surface 20A of the glass article 20T, but this is not limited thereto. The inclination angle of the end faces (ground surfaces 20E) of these openings relative to the normal AX of the main surface 20A is preferably 70° or less, more preferably 0° or more and 60° or less, and even more preferably 0° or more and 45° or less. Note that the end faces of the openings here refer to the polished surfaces 20E, and in the case where chamfered portions (chamfered portions 12E2, 13E2) are formed on the openings 12HT and 14HT as described below, refer to the portions excluding the chamfered portions (side surface portions 12E1, 14E1). Furthermore, the normal line AX of the main surface 20A here may refer to the normal line AX of the main surface 20A at the boundary position between the end surface of the opening and the main surface 20A. If the inclination angle of the end surface is within this range, the opening can be set in an appropriate orientation even if, for example, the glass article 20T is attached to a vehicle at an angle.

[0094] (Chamfered portion on the periphery of the opening) Figure 15 is a schematic cross-sectional view of a glass article according to the second embodiment. For convenience of explanation, the functional layer 50 and the shielding layer 60 are omitted in Figure 15, but the functional layer 50 and the shielding layer 60 may be provided. Note that the glass article 20T has a shape in which the openings (opening H, opening 12HT, opening 50HT, opening 40HT, opening 14HT, and opening 60HT) are hollowed out, and the cross-sectional view of the glass article 20T shown in Figure 15 shows the side of the opening toward the back of the page (indicated by a solid line). As shown in Figure 15, in the second embodiment, the first glass article 12b has a chamfered portion 12E2 formed on the periphery of the opening 12HT on the main surface 12A, and preferably does not have a chamfered portion formed on the periphery of the opening 12HT on the main surface 12B. That is, if the end surface (ground surface) surrounding the opening 12HT of the first glass article 12b is defined as the end surface 12E, the end surface 12E includes a side portion 12E1 and a chamfered portion 12E2. The chamfered portion 12E2 is a chamfered surface formed between the side portion 12E1 and the main surface 12A in the Z direction, connecting the side portion 12E1 and the main surface 12A. The chamfered portion 12E2 is inclined with respect to both the side portion 12E1 and the main surface 12A when viewed from a direction perpendicular to the Z direction (the Y direction in the example of FIG. 15). The chamfered portion 12E2 may be flat (i.e., C-chamfered) or curved (R-chamfered). On the other hand, the first glass article 12b does not have a chamfered portion formed between the side portion 12E1 and the main surface 12B. "No chamfered portion" may mean that, when viewed from a direction perpendicular to the Z direction (the Y direction in the example of FIG. 15), the distance between the boundary point between main surface 12B and the plane intersecting main surface 12B and the boundary point between side surface portion 12E1 and the plane intersecting side surface portion 12E1 is 50 μm or less. That is, for example, in the example of FIG. 15, side surface portion 12E1 and main surface 12B are directly connected, so the boundary point between main surface 12B and the plane intersecting main surface 12B (side surface portion 12E1) coincides with the boundary point between side surface portion 12E1 and the plane intersecting side surface portion 12E1 (main surface 12B), and the distance therebetween is 0 μm.

[0095] Furthermore, in the second embodiment, the second glass article 14b preferably has a chamfered portion 14E2 formed around the periphery of the opening 14HT on the main surface 14B, and no chamfered portion formed around the periphery of the opening 14HT on the main surface 14A. That is, if the end surface (ground surface) surrounding the opening 14HT of the second glass article 14b is defined as the end surface 14E, the end surface 14E includes a side surface 14E1 and a chamfered portion 14E2. The chamfered portion 14E2 is a chamfered surface formed between the side surface 14E1 and the main surface 14B in the Z direction, connecting the side surface 14E1 and the main surface 14B. The chamfered portion 14E2 is inclined with respect to both the side surface 14E1 and the main surface 14B when viewed from a direction perpendicular to the Z direction (the Y direction in the example of FIG. 15 ). The chamfered portion 14E2 may be flat (i.e., C-chamfered) or curved (R-chamfered). On the other hand, the second glass article 14b does not have a chamfered portion formed between the side surface portion 14E1 and the main surface 14A.

[0096] In this way, by not forming a chamfered portion on the periphery of the openings 12HT, 14HT of the first glass article 12b and the second glass article 14b on the side of the intermediate layer 40, the contact area between the first glass article 12b (second glass article 14b) and the intermediate layer 40 can be increased, and the adhesive strength between the first glass article 12b (second glass article 14b) and the intermediate layer 40 can be increased. On the other hand, by forming a chamfered portion on the periphery of the openings 12HT, 14HT on the side opposite the intermediate layer 40, components can be inserted appropriately. Note that in this embodiment, because the outer peripheral surfaces of the openings in each layer are ground simultaneously, it is possible to form a chamfered portion on the main surfaces 12A, 14B side, but not form a chamfered portion on the main surfaces 12B, 14A side.

[0097] Furthermore, the width ΔE1 of the chamfered portion 12E2 on the main surface 12A of the first glass article 12b is preferably smaller than the width of the chamfered portion 14E2 on the main surface 14B of the second glass article 14b. This allows the width ΔE1 of the chamfered portion 12E2 on the vehicle exterior side to be kept small, making it suitable for use as a window member for vehicles. Note that the width ΔE1 is the length of the chamfered portion 12E2 as viewed from a direction perpendicular to the Z direction. For example, in the example of FIG. 15, it refers to the distance in the X direction from the boundary position between the main surface 12A and the chamfered portion 12E2 to the boundary position between the side surface portion 12E1 and the chamfered portion 12E2. The same applies to the width ΔE2. Furthermore, the width ΔE1 is preferably 0.5 mm or less. By reducing the chamfer width on the vehicle exterior side in this manner, it makes it suitable for use as a window member for vehicles.

[0098] (Grinding Wheel) FIGS. 16 and 17 are schematic diagrams of a grinding wheel in the second embodiment. The grinding wheel W used to grind the cut surface 20C of each layer of the glass plate 20 may have any structure. However, in the second embodiment, since the intermediate layer 40 is also ground, it is preferable to devise a structure for the grinding wheel W. Specifically, as shown in FIGS. 16 and 17, the grinding wheel W used in the second embodiment has a disk shape whose outer peripheral surface forms a grinding surface WA, and it is preferable that multiple grooves GR are formed on the outer peripheral surface (grinding surface WA) along the circumferential direction. That is, this grinding wheel W has multiple abrasive grains in areas of the grinding surface WA where no grooves GR are formed. By using such a grinding wheel W, the grinding surface WA and the grooves GR can properly grind the intermediate layer 40, thereby allowing each layer of the glass plate 20 to be properly ground. The groove GR may extend in a direction inclined with respect to the rotation axis of the grinding wheel W as shown in FIG. 16, or may extend along the rotation axis of the grinding wheel W as shown in FIG.

[0099] (Modification of the Second Embodiment) In the second embodiment, the glass base material 1 may be used, for example, as a cover glass for a vehicle sensor. When the glass article 20T is used as a cover glass for a vehicle sensor, it may be used as a cover glass for a LiDAR or a camera. As a cover glass for a vehicle sensor, a material that transmits near-infrared rays of 750 nm to 1650 nm may have, for example, the following composition in mole percent based on oxide: SiO ２ 55% to 85% AI ２ O ３ 0% to 30% B ２ O ３ 0% to 20% Na ２ O 0%~25% CaO 0%~20% MgO 0%~15% K ２ O 0% to 20% BaO 0% to 20%. By providing an opening in the cover glass for a vehicle sensor using the method of this embodiment, for example, a member that transmits far-infrared rays with a wavelength of 8 μm to 14 μm can be inserted into the opening, and a far-infrared transmitting camera can also be installed.

[0100] (Effects) As described above, the manufacturing method according to the first aspect of the present disclosure includes: setting an imaginary line R on the main surface 10A of the glass preform 1 including the glass substrate 10 having a thickness of 0.4 mm or more; irradiating the glass preform 1 along the imaginary line R with laser light L having a wavelength of 9.1 μm or more and 10.8 μm or less to cut the glass preform 1 along the imaginary line R and separating the portion surrounded by the imaginary line R from the glass preform 1 to obtain a glass plate 20; and grinding the cut surface 20C of the glass plate 20 with a grindstone W to obtain a glass article 20T. The virtual line R has a starting point P1 and an ending point P3 located on the end surface 10C of the glass base material 1, and has a shape having a locus that is recessed inward in the in-plane direction on the main surface 10A of the glass base material 1, or a shape having a closed curve, and the perimeter of the virtual line R is 60 mm or more. By cutting by irradiating the laser light L, a damaged layer 20D is formed on the cut surface 20C of the glass plate 20, and the width D of the damaged layer 20D satisfies formula (1), and the damaged layer 20D is removed by grinding with the grinding wheel W. According to the present disclosure, the glass base material 1 is cut using laser light L having a wavelength within the above range so that the width D of the damaged layer 20D falls within the range of formula (1). This allows the glass base material 1 to be cut appropriately while suppressing deterioration in the quality of the ground surface 20E, such as chipping. Furthermore, by not making the width D of the damaged layer 20D too large, the grinding time with the grindstone W for removing the damaged layer 20D can be shortened, and the glass article 20T of the desired shape can be obtained efficiently.

[0101] The manufacturing method according to the second aspect of the present disclosure is the manufacturing method according to the first aspect, and preferably, the width D of the damaged layer 20D satisfies formula (2). By setting the width D within this range, the glass article 20T can be obtained efficiently while suppressing deterioration in quality.

[0102] A manufacturing method according to a third aspect of the present disclosure is the manufacturing method according to the first or second aspect, wherein the virtual line R preferably includes a first section R1 from the start point P1 to the intermediate point P2, and a second section R2 that passes through a locus surrounding the start point P1 and returns to the intermediate point P2 (end point P3). By setting the virtual line R in this manner, a glass article 20T having an opening H formed therein can be appropriately manufactured.

[0103] A manufacturing method according to a fourth aspect of the present disclosure is the manufacturing method according to the third aspect, wherein the first section R1 and the second section R2 are preferably continuously connected. By setting the virtual line R in this manner, it is possible to suppress the occurrence of residual thermal stress due to fluctuations in irradiation energy near the midpoint P2, thereby improving quality.

[0104] A manufacturing method according to a fifth aspect of the present disclosure is the manufacturing method according to the third or fourth aspect, and preferably further comprises: setting an auxiliary virtual line RA connected to a second section R2 of the virtual line R and extending to a point P4 at a position different from the end point P3 of the second section R2; moving the irradiation position of the laser light L along the virtual line R relative to the glass preform 1 while irradiating the laser light L in the first section R1 and the second section R2 of the virtual line R; and moving the irradiation position along the auxiliary virtual line RA while halting the laser light irradiation in the section where the auxiliary virtual line RA is set. By setting the auxiliary virtual line RA in this manner, it is possible to suppress the occurrence of residual thermal stress due to fluctuations in irradiation energy near the midpoint P2 (end point P3), thereby improving quality.

[0105] A manufacturing method according to a sixth aspect of the present disclosure is the manufacturing method according to any one of the first to fifth aspects, wherein the glass preform 1 preferably has a curved portion. According to the present disclosure, the glass article 20T can be appropriately obtained from the curved glass preform 1.

[0106] A manufacturing method according to a seventh aspect of the present disclosure is the manufacturing method according to any one of the first to sixth aspects, wherein the glass base material 1 is preferably laminated glass having a first glass substrate 12, a second glass substrate 14, and an intermediate layer 40 provided between the first glass substrate 12 and the second glass substrate 14. According to the present disclosure, a glass article 20T can be appropriately obtained from the laminated glass.

[0107] A manufacturing method according to an eighth aspect of the present disclosure is the manufacturing method according to the seventh aspect, wherein the grinding wheel W is preferably disk-shaped with an outer peripheral surface that forms the grinding surface WA, and the outer peripheral surface is preferably formed with a plurality of grooves GR aligned in the circumferential direction. According to the present disclosure, by using such a grinding wheel W, the intermediate layer 40 can be appropriately ground away, and the glass article 20T can be appropriately obtained from the laminated glass.

[0108] A manufacturing method according to a ninth aspect of the present disclosure is the manufacturing method according to any one of the first to eighth aspects, wherein when grinding the cut surface 20C of the glass plate 20 with the grinding wheel W, it is preferable to grind the cut surface 20C with a first grinding wheel having abrasive grains with a median diameter D50 of 30 μm to 50 μm, and then grind the cut surface 20C with a second grinding wheel having abrasive grains with a median diameter D50 of 10 μm to 25 μm. According to the present disclosure, by grinding in stages using grinding wheels having abrasive grains of different diameters in this manner, deterioration in the quality of the ground surface 20E, such as chipping, can be suppressed.

[0109] The manufacturing method according to the tenth aspect of the present disclosure is a manufacturing method according to any one of the first to ninth aspects, and when grinding the cut surface 20C of the glass plate 20 with the grinding wheel W, it is preferable that the feed speed of the grinding wheel W is 200 mm / min or more and 3000 mm / min or less.

[0110] A glass article 20T according to an eleventh aspect of the present disclosure includes a first glass article 12b having a thickness t of 0.4 mm or more, a second glass article 14b having a thickness t of 0.4 mm or more, and an intermediate layer 40 disposed between the first glass article 12b and the second glass article 14b, wherein the first glass article 12b and the second glass article 14b have openings 12HT and 14HT having a perimeter of 60 mm or more, the opening 12HT of the first glass article 12b and the opening 14HT of the second glass article 14b overlapping each other as viewed in the thickness direction (Z direction) of the glass article 20T, and the misalignment between the end faces of the openings 12HT and 14HT in the in-plane direction of the glass article 20T is 100 μm or less. According to the present disclosure, by keeping the misalignment of the end faces within this range, the misalignment between the openings as viewed in the Z direction is small, thereby suppressing a decrease in quality from a dimensional standpoint.

[0111] A glass article 20T according to a twelfth aspect of the present disclosure is the glass article 20T according to the eleventh aspect, wherein the first glass article 12b has a chamfered portion 12E2 formed on the periphery of the opening 12HT on the main surface 12A opposite the intermediate layer 40, and no chamfered portion formed on the periphery of the opening 12HT on the main surface 12B opposite the main surface 12A, and the second glass article 14b has a chamfered portion 14E2 formed on the periphery of the opening 14HT on the main surface 14B opposite the intermediate layer 40, and no chamfered portion formed on the periphery of the opening 14HT on the main surface 14A opposite the main surface 14B. This makes it possible to increase the contact area between the first glass article 12b (second glass article 14b) and the intermediate layer 40, and to appropriately bond the first glass article 12b (second glass article 14b) and the intermediate layer 40 together.

[0112] A glass article 20T according to a thirteenth aspect of the present disclosure is the glass article 20T according to the twelfth aspect, wherein the first glass article 12b and the second glass article 14b are curved so as to be convex in direction Z1 (first direction), and a width ΔE1 of the chamfered portion 12E2 of the opening 12HT on the main surface 12A of the first glass article 12b is preferably smaller than a width ΔE2 of the chamfered portion 14E2 of the opening 14HT on the main surface 14B of the second glass article 14b. This allows the glass article 20T to be suitably used as a window member for vehicles.

[0113] A glass article 20T according to a fourteenth aspect of the present disclosure is the glass article 20T according to any of the eleventh to thirteenth aspects, and further includes a shielding layer 60 that blocks light and is provided at a position that overlaps the first glass article 12b and the second glass article 14b when viewed from the Z direction, and preferably has an opening 60HT formed in the shielding layer 60 that overlaps the openings 12HT and 14HT. By providing the shielding layer 60 in this manner and forming the opening 60HT in the shielding layer 60, the glass article 20T can be suitably used as a window member for an automobile.

[0114] A glass article 20T according to a fifteenth aspect of the present disclosure is the glass article 20T according to any one of the eleventh to fourteenth aspects, and further includes a heating layer (functional layer 50) that generates heat and is provided at a position that overlaps the first glass article 12b and the second glass article 14b when viewed from the Z direction, and preferably has openings 50HT formed in the heating layer that overlap the openings 12HT and 14HT. By providing the heating layer in this manner and forming the openings 50HT in the heating layer, the glass article 20T can be suitably used as a window member for an automobile.

[0115] A glass article 20T according to a sixteenth aspect of the present disclosure is the glass article 20T according to any of the eleventh to fifteenth aspects, wherein the inclination angle of the end face of the opening 12HT of the first glass article 12b relative to the normal AX of the main surface 20A of the glass article 20T is 70° or less, and the inclination angle of the end face of the opening 14HT of the second glass article 14b relative to the normal AX of the main surface 20A of the glass article 20T is 70° or less. This allows the opening to be kept facing an appropriate direction, such as forward, even when the glass article 20T is attached to a vehicle at an angle, for example.

[0116] A glass article 20T according to a seventeenth aspect of the present disclosure is the glass article 20T according to any one of the eleventh to sixteenth aspects, wherein the opening 12HT of the first glass article 12b and the opening 14HT of the second glass article 14b preferably have a distance of 1 mm or more between the inscribed circle of the opening and the edge of the opening. By forming the openings in this shape, the field of view (FOV) of the sensor can be widened in the major axis direction (the direction in which the width is long), thereby enabling detection by the sensor to be performed favorably.

[0117] A glass article 20T according to an eighteenth aspect of the present disclosure is the glass article 20T according to any one of the eleventh to seventeenth aspects, and preferably has a curved portion, which allows the glass article 20T to be used in various applications requiring curvature.

[0118] The glass article 20T according to a nineteenth aspect of the present disclosure is the glass article 20T according to any one of the eleventh to eighteenth aspects, and is preferably used as a vehicle windshield or a cover glass for a vehicle sensor. The glass article 20T according to the present disclosure can be suitably used for these applications.

[0119] EXAMPLES Next, examples will be described. Tables 1 and 2 show the manufacturing conditions and evaluation results of each example.

[0120]

[0121] (Example 1) In Example 1, a glass base material consisting of a single glass substrate with a thickness t of 0.4 mm was prepared. A Dragontrail (registered trademark) manufactured by AGC was used as the glass base material. A roughly rectangular imaginary line measuring 50 mm in length, 100 mm in width, and with a radius of 10 mm at each of the four vertices was set on this glass base material. Using a Mitsubishi Electric ML3122VZ20 laser cutter, a continuous laser beam was irradiated along the imaginary line while air was sprayed as the gas under the following conditions to cut the glass base material along the imaginary line. The area surrounded by the imaginary line was then cut out from the glass base material, and the remaining portion was obtained as a glass plate. Wavelength: 10.6 μm Laser output: 200 W Feed rate (scanning rate): 1200 mm / min Irradiation diameter: 0.2 mm Air flow rate: 116 L / min

[0122] The cut surface of the obtained glass plate was observed under a microscope to measure the width D of the damaged layer. The measurement results are shown in Table 1.

[0123] The cut surface of the obtained glass plate was subjected to a first grinding using a grinding wheel having abrasive grains with a grit size of SD400P and a median diameter D50 of 37.9 μm, and then a second grinding using a grinding wheel having abrasive grains with a grit size of SD800P and a median diameter D50 of 16.2 μm on the cut surface after the first grinding, thereby obtaining a glass article. The removal allowance for the first grinding was 1.8 mm, and the removal allowance for the second grinding was 0.1 mm.

[0124] Examples 2 to 10 In Examples 2 to 10, glass articles were obtained in the same manner as in Example 1, except that the production conditions were as shown in Table 1.

[0125] (Examples 11 to 12) In Examples 11 to 12, the glass base material was a laminated glass made of soda-lime glass and a first glass substrate having a thickness t of 2 mm, a second glass substrate having a thickness t of 2 mm, an intermediate layer made of PVB having a thickness of 0.78 mm provided between the first and second glass substrates, and soda-lime glass. Soda-lime glass manufactured by AGC was used as the first and second glass substrates. In Examples 11 to 12, glass articles were obtained in the same manner as in Example 1, except that the manufacturing conditions were as shown in Table 2.

[0126] (Example 13) In Example 13, the same laminated glass as in Example 11 was used as the glass base material. A concave locus was set on this glass base material, with the start point and end point on the same side and recessed inward in the in-plane direction. For Example 13, a glass article was obtained in the same manner as in Example 1, except that the manufacturing conditions were as shown in Table 2.

[0127] (Evaluation) For each example, the cuttability, processing time, and quality of the glass article were evaluated. In the evaluation of cuttability, if the area surrounded by the imaginary line could be cut out from the cut glass base material and a glass plate was obtained, it was marked as ◯, and if the area surrounded by the imaginary line could not be cut out and a glass plate could not be obtained, it was marked as ×. Note that for examples where cuttability was not possible, grinding with a grindstone and evaluation of processing time and quality were not performed. In the evaluation of processing time, the total time (minutes) required for cutting the glass base material and the time required for grinding the glass plate was calculated as the processing time. In the evaluation of quality, if there were no chips or gaps on the glass surface in contact with the ground surface of the glass article, it was marked as ◯, and if there were chips or gaps, it was marked as ×.

[0128] In the evaluation of Examples 1 to 10, a product was judged to pass if it satisfied all of the following criteria: cutout feasibility was 0, processing time was 2 minutes or less, and quality was 0; a product was judged to fail if it did not satisfy at least one of these criteria. In the evaluation of Examples 11 and 12, a product was judged to pass if it satisfied all of the following criteria: cutout feasibility was 0, processing time was 3 minutes or less, and quality was 0; a product was judged to fail if it did not satisfy at least one of these criteria.

[0129] The working examples, Examples 1, 3-4, 6-8, 11, and 13, passed the test, demonstrating that glass articles of the desired shape could be efficiently obtained while suppressing deterioration in quality. On the other hand, in Comparative Examples 2 and 5, the width of the damage layer was below the lower limit (0.2t) of Equation (1) and was too small, so the glass base material could not be properly cut and cut-out was not possible. Furthermore, in Comparative Example 9, the width of the damage layer exceeded the upper limit (2000 μm) of Equation (1) and was too large, so deterioration in quality could not be suppressed. Furthermore, in Comparative Example 10, cutting with a grindstone lengthened the processing time, and a glass article could not be efficiently obtained. Furthermore, in Comparative Example 12, the laminated glass could not be cut with a grindstone and cut-out was not possible.

[0130] Although the embodiments of the present invention have been described above, the embodiments are not limited to the contents of these embodiments. Furthermore, the above-described components include those that can be easily imagined by a person skilled in the art, those that are substantially the same, and those that are within the scope of what is called equivalents. Furthermore, the above-described components can be combined as appropriate. Furthermore, various omissions, substitutions, or modifications of the components can be made without departing from the spirit of the above-described embodiments.

[0131] REFERENCE SIGNS LIST 1 glass base material 10 glass substrate 10A first principal surface, second principal surface 20 glass plate 20C cut surface 20D damaged layer 20E ground surface 20T glass article D width R imaginary line

Claims

1. A method for manufacturing a glass article, comprising: setting a virtual line on a main surface of a glass base material including a glass substrate having a thickness of 0.4 mm or more; irradiating a laser beam having a wavelength of 9.1 μm or more and 10.8 μm or less along the virtual line to cut the glass base material along the virtual line and separate a portion surrounded by the virtual line from the glass base material to obtain a glass plate; and grinding the cut surface of the glass plate with a grinding wheel to obtain a glass article, wherein the virtual line has a shape having a locus whose start point and end point are located on an end face of the glass base material and which is recessed inward in an in-plane direction on the main surface of the glass base material, or a shape having a closed curve, the perimeter of the virtual line is 60 mm or more, cutting by the irradiation of the laser beam forms a damage layer on the cut surface of the glass plate, and a width D of the damage layer satisfies the following formula (1), and the damage layer is removed by grinding with the grinding wheel. 0.2·t≦D≦2000 μm (1) Here, t is the thickness (μm) of the glass base material.

2. The method for manufacturing a glass article according to claim 1, wherein the width D of the damage layer satisfies the following formula (2): 0.2·t+100 μm≦D≦2000 μm (2) 3. A method for manufacturing a glass article as described in claim 1 or claim 2, wherein the virtual line includes a first section from a starting point to an intermediate point, and a second section that passes through a trajectory surrounding the starting point and returns to the intermediate point.

4. A method for manufacturing a glass article as described in claim 3, wherein the first section and the second section are continuously connected.

5. A method for manufacturing a glass article as described in claim 3, wherein, when setting the virtual line, a preliminary virtual line is further set, the preliminary virtual line being connected to the second section of the virtual line and extending to a point located at a position different from an end point of the second section; in the first and second sections of the virtual line, the irradiation position of the laser light is moved along the virtual line relative to the glass base material while irradiating the laser light; and in the section where the preliminary virtual line is set, the irradiation position is moved relatively along the preliminary virtual line while the irradiation of the laser light is stopped.

6. A method for manufacturing a glass article according to claim 1 or 2, wherein the glass base material has a curved portion.

7. A method for manufacturing a glass article as described in claim 1 or claim 2, wherein the glass base material is a laminated glass having a first glass substrate, a second glass substrate, and an intermediate layer provided between the first glass substrate and the second glass substrate.

8. The method for manufacturing a glass article according to claim 7, wherein the grinding wheel is disk-shaped with an outer peripheral surface serving as the grinding surface, and a plurality of grooves aligned in the circumferential direction are formed on the outer peripheral surface.

9. A method for manufacturing a glass article as described in claim 1 or claim 2, wherein, when grinding the cut surface of the glass plate with a grinding wheel, the cut surface is first ground with a first grinding wheel having abrasive grains with a median diameter D50 of 30 μm or more and 50 μm or less, and then the cut surface is ground with a second grinding wheel having abrasive grains with a median diameter D50 of 10 μm or more and 25 μm or less.

10. A method for manufacturing a glass article as described in claim 1 or 2, wherein when the cut surface of the glass plate is ground with a grinding wheel, the feed speed of the grinding wheel is 200 mm / min or more and 3000 mm / min or less.

11. A glass article comprising a first glass article having a thickness of 0.4 mm or more, a second glass article having a thickness of 0.4 mm or more, and an intermediate layer provided between the first glass article and the second glass article, wherein an opening having a perimeter of 60 mm or more is formed in the first glass article and the second glass article, the opening in the first glass article and the opening in the second glass article overlap when viewed in the thickness direction of the glass article, and the amount of misalignment in the in-plane direction of the glass article between the end face of the opening in the first glass article and the end face of the opening in the second glass article is 100 μm or less.

12. The glass article of claim 11, wherein the first glass article has a chamfered portion formed around the periphery of the opening in a first main surface opposite the intermediate layer and no chamfered portion formed around the periphery of the opening in a second main surface opposite the first main surface; and the second glass article has a chamfered portion formed around the periphery of the opening in a first main surface opposite the intermediate layer and no chamfered portion formed around the periphery of the opening in a second main surface opposite the first main surface of the second glass article.

13. The glass article of claim 12, wherein, when a direction from the second glass article to the first glass article is defined as a first direction, the first glass article and the second glass article are curved so as to be convex in the first direction, and the width of the chamfered portion of the opening on the first main surface of the first glass article is smaller than the width of the chamfered portion of the opening on the first main surface of the second glass article.

14. A glass article as described in any one of claims 11 to 13, further comprising a shielding layer for blocking light, which is provided at a position overlapping the first glass article and the second glass article when viewed in the thickness direction of the glass article, and the shielding layer has an opening formed therein which overlaps with the opening of the first glass article and the opening of the second glass article.

15. A glass article as described in any one of claims 11 to 13, further comprising a heating layer that generates heat and is provided at a position overlapping the first glass article and the second glass article when viewed in the thickness direction of the glass article, the heating layer having openings formed therein that overlap with the openings of the first glass article and the openings of the second glass article.

16. A glass article as described in any one of claims 11 to 13, wherein the inclination angle of the end face of the opening of the first glass article with respect to the normal to the main surface of the glass article is 70° or less, and the inclination angle of the end face of the opening of the second glass article with respect to the normal to the main surface of the glass article is 70° or less.

17. A glass article according to any one of claims 11 to 13, wherein the openings in the first glass article and the second glass article have a distance between the inscribed circle of the opening and the edge of the opening that is 1 mm or more.

18. The glass article according to any one of claims 11 to 13, wherein the glass article has a curved portion.

19. The glass article according to any one of claims 11 to 13, which is used as a windshield of a vehicle or a cover glass for a sensor of a vehicle.

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