JP2014210670A - Production method of tempered glass panel - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a production method of a tempered glass panel excellent in production efficiency.SOLUTION: A production method of a tempered glass panel in an embodiment 1 includes steps of: laminating each main surface of a plurality of tempered glass plates 10 with each adhesion layer 11 so as to be laminated in the thickness direction; cutting out a plurality of laminated tempered glass panels 10a from a plurality of laminated tempered glass plates 10 by internal heating cutting; and removing each adhesion layer 11 from the plurality of laminated tempered glass panels 10a.

Description

  The present invention relates to a method for producing a tempered glass panel, and more particularly to a method for producing a tempered glass panel by cutting out a tempered glass panel from a tempered glass plate using internal heating by laser or plasma.

  In portable devices such as mobile phones and personal information terminals (PDAs), glass plates are used for display covers and substrates. Due to demands for thinning and weight reduction in portable devices, thinning and weight reduction have been achieved by using high strength tempered glass plates.

  By the way, the glass plate is usually cut by introducing a scribe line mechanically into the main surface with a hard roller or chip such as diamond and applying a bending force along the scribe line. In such a technique, a lot of fine cracks are generated on the cut end face of the glass plate by introducing the scribe line. Accordingly, there is a problem that a sufficient strength cannot be obtained at the cut end despite the tempered glass plate.

  In recent years, a method has been developed to cut the glass plate by heating the inside of the glass plate with a laser or plasma and controlling the extension of the initial cracks introduced into the end face instead of the main surface of the glass plate. (Hereinafter referred to as internal heating cutting). In such internal heating cutting, it is not necessary to introduce a scribe line to the main surface of the glass plate as in the prior art. Therefore, the above-mentioned fine crack is not generated on the cut end face, and a high-strength glass plate can be obtained. Patent Document 1 discloses a method for cutting a glass plate with laser light in this way.

International Publication No. 2010/126977

The inventor has found the following problems regarding internal heating cutting of a tempered glass sheet.
As shown in FIG. 10A, when cutting out the panel portion 10a to be used from the tempered glass plate 10, first, the cutting line 301 is continuously cut from one auxiliary cutting line 302a (that is, cut with a single stroke), The panel part 10a and the unnecessary peripheral part 10b are divided | segmented. Further, for example, the internal heating cut along the three auxiliary cutting lines 302b is performed, and the peripheral portion 10b is divided into four parts and then removed, thereby removing the panel portion 10a as shown in FIG. 10B.

  Thus, the panel part 10a needed to cut out one sheet at a time, and there existed a problem that it was inferior to production efficiency.

  This invention is made | formed in view of the above, Comprising: It aims at providing the manufacturing method of the tempered glass panel which is excellent in production efficiency.

  The manufacturing method of the tempered glass panel which concerns on aspect 1 of this invention is the process of bonding the main surfaces of several tempered glass board with an adhesive layer, and laminating | stacking on the thickness direction, and the said several tempered glass board laminated | stacked Then, a step of cutting out the plurality of laminated tempered glass panels by internal heat cutting and a step of removing the adhesive layer from the plurality of laminated tempered glass panels are provided. Thereby, a several tempered glass panel can be cut | disconnected at once, and the manufacturing method of the tempered glass panel which is excellent in production efficiency can be provided.

  The manufacturing method of the tempered glass panel which concerns on aspect 2 of this invention is the aspect 1 of the said invention WHEREIN: Before the step which removes the said adhesive layer, the step which grind | polishes the end surface of these laminated | stacked several tempered glass panels is carried out. Furthermore, it is characterized by providing. Thereby, since the tempered glass panel is already laminated | stacked in the cut | disconnected state, and the cut end surface is also uniform, the manufacturing method of the tempered glass panel which is further excellent in production efficiency can be provided.

  The method for producing a tempered glass panel according to aspect 3 of the present invention is characterized in that, in aspect 1 or 2 of the above invention, the internal heating cutting is a cutting with a laser beam. In the present invention, cutting with a laser beam is particularly preferable among internal heating cutting.

  The method for producing a tempered glass panel according to aspect 4 of the present invention is characterized in that, in aspect 3 of the invention, the light source of the laser light is a fiber laser. In the present invention, a fiber laser is particularly suitable as a laser light source.

  In the method for producing a tempered glass panel according to aspect 5 of the present invention, in the aspect 3 or 4 of the present invention, the adhesive layer is provided at a position where the plurality of laminated tempered glass plates are cut by the laser beam. It is not formed. Thereby, absorption of the laser beam by an adhesive layer can be prevented.

  The method for producing a tempered glass panel according to Aspect 6 of the present invention is the method for producing a tempered glass panel according to any one of Aspects 3 to 5, wherein the laser light absorption rate of each of the laminated tempered glass plates is 10%. It is characterized by being less than. Thereby, the plurality of laminated tempered glass plates can be reliably cut.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the tempered glass panel which is excellent in production efficiency can be provided.

It is a flowchart which shows the manufacturing method of the tempered glass panel which concerns on the 1st Embodiment of this invention. It is a top view which shows the cutting method of the tempered glass panel which concerns on the 1st Embodiment of this invention. It is sectional drawing which shows the cutting method of the tempered glass panel which concerns on the 1st Embodiment of this invention. It is sectional drawing of the tempered glass panel obtained by laser cutting. It is sectional drawing for demonstrating the grinding | polishing method. 3 is a plan view showing a state in which a tempered glass plate 500 larger than the tempered glass plate 10 is laminated with an adhesive layer 11. FIG. 2 is a cross-sectional view showing a state in which a tempered glass plate 500 larger than the tempered glass plate 10 is laminated with an adhesive layer 11. FIG. It is a perspective view for demonstrating the cutting method of a tempered glass board. It is sectional drawing of the tempered glass board before irradiating a laser beam. It is a schematic diagram which shows distribution of the residual stress of the tempered glass board before irradiating a laser beam. It is sectional drawing along the AA line of FIG. It is sectional drawing along the BB line of FIG. It is a figure for demonstrating the subject which invention will solve. It is a figure for demonstrating the subject which invention will solve.

  Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings. However, the present invention is not limited to the following embodiment. In addition, for clarity of explanation, the following description and drawings are simplified as appropriate.

(Embodiment 1)
With reference to FIG. 1, 2A-2C, the manufacturing method of the tempered glass panel which concerns on the 1st Embodiment of this invention is demonstrated. FIG. 1 is a flowchart showing a method for manufacturing a tempered glass panel according to the first embodiment of the present invention. FIG. 2A is a plan view showing a method of cutting a tempered glass panel according to the first embodiment of the present invention. FIG. 2B is a cross-sectional view illustrating a method for cutting a tempered glass panel according to the first embodiment of the present invention. FIG. 2C is a cross-sectional view of a laminated tempered glass panel obtained by laser cutting. Below, the case where a tempered glass board is cut | disconnected by internal heating cutting | disconnection using a laser beam and a tempered glass panel is taken out is demonstrated.

  First, as shown in step ST1 of FIG. 1, the main surfaces of a plurality of tempered glass plates 10 are attached to each other with an adhesive layer 11 and laminated in the thickness direction. Here, the formation position of the adhesive layer 11 is not particularly limited as long as the tempered glass plates 10 can be bonded to each other. However, the adhesive layer 11 absorbs the laser light 20. Therefore, as shown in FIGS. 2A and 2B, it is preferable that the laser beam 20 is not formed at a position where the laser beam 20 is irradiated, that is, a position where the cutting line 301 and the auxiliary cutting line 302 are introduced. In other words, the adhesive layer 11 is preferably formed at a position other than the position where the laser beam 20 is irradiated. In the example of FIG. 2B, five tempered glass plates 10 are bonded together by four layers of adhesive layers 11, but any n (n is a natural number of 2 or more) tempered glass plates 10 (n− 1) It can bond together by the adhesion layer 11 of a layer.

  As the adhesive layer 11, for example, a photocurable resin or a thermosetting resin can be used. In particular, since the tempered glass plate 10 can transmit light, a photocurable resin typified by an ultraviolet (UV) curable resin can be used. Since the photocurable resin does not require a heating step, the tempered glass plate 10 is not damaged and is excellent in productivity, and is particularly preferable.

  Next, as shown in step ST <b> 2 of FIG. 1, the laminated tempered glass plate 10 is laser-cut to cut out the laminated panel portion 10 a. Specifically, first, as shown in FIG. 2A, the laminated tempered glass plate 10 is placed and held on, for example, a vacuum suction table 101. Here, a vacuum path is branched and formed inside the vacuum suction table 101. Therefore, the laminated tempered glass plate 10 can be vacuum-sucked over the entire table.

  Then, an initial crack is introduced into the end face (the lower end face in FIG. 2A) of each tempered glass plate 10, and the auxiliary cutting line 302 that is substantially perpendicular to the end face with respect to each tempered glass plate 10 starts from this initial crack. Is introduced by laser cutting. Next, as shown in FIG. 2A, a cutting line 301 continuous with the auxiliary cutting line 302 is introduced, and the tempered glass plate 10 is laser-cut along the shape of the panel portion 10a. That is, the auxiliary cutting line 302 and the cutting line 301 are written with one stroke. Thereby, the tempered glass board 10 is divided | segmented into the panel part 10a and the peripheral part 10b. In addition, the detail of the cutting method of the tempered glass board using a laser beam is mentioned later.

  Here, the laser beam absorptance of one tempered glass plate 10 is less than 10%. That is, 90% or more of the irradiated laser beam is transmitted, and the energy utilization efficiency is low. On the other hand, since the laser light absorption rate of one tempered glass plate 10 is low, even when a plurality of tempered glass plates 10 are laminated as in the present embodiment, the same as the case of one sheet. Can be cut with energy. Therefore, energy use efficiency improves, so that the number of the laminated tempered glass boards 10 is increased. As a matter of course, as the number of laminated tempered glass plates 10 is increased, the productivity is improved as compared with the case of cutting one by one.

  Next, as shown in step ST3 of FIG. 1, the cut end surface of the panel portion 10a obtained by the laser cutting is polished according to the application. Conventionally, a plurality of cut out panel portions 10a are bonded together with an adhesive and overlapped in the thickness direction, and then the cut end surface is polished. Here, when a plurality of panel portions 10a are attached to each other, it is difficult to align the cut end faces, resulting in poor production efficiency. On the other hand, in the manufacturing method according to the present embodiment, as shown in FIG. 2C, the stacked panel portions 10a are already cut and end surfaces are aligned in a laser cut state, so that alignment is not necessary. . Therefore, the manufacturing method according to the present embodiment is more productive than the conventional method in which the panel portions 10a are cut out one by one by laser cutting and then the plurality of panel portions 10a are bonded together. Note that step ST3 is not an indispensable step because it is performed depending on the application.

  Here, the polishing method will be described in more detail with reference to FIG. FIG. 3 is a cross-sectional view for explaining a polishing method. As shown in FIG. 3, since the cut end surfaces of the laminated panel portions 10a are aligned, the cut end surfaces of the panel portions 10a are evenly polished. Here, each adhesive layer 11 preferably has substantially the same shape as viewed from the stacking direction. Also, as shown in FIG. 3, since the end face of each adhesive layer 11 is located inside the panel portion 10a, a groove-like gap 430 is formed by each adhesive layer 11 and the two panel portions 10a sandwiching the end face. Is formed.

  The polishing brush 400 is a roll brush as shown in FIG. 3, and includes a rotating shaft 401 parallel to the stacking direction of the stacked panel portions 10 a and brush hairs 402 held substantially perpendicular to the rotating shaft 401. It has. The brush 400 relatively moves along the cut end surfaces of the stacked panel portions 10 a while rotating around the rotation shaft 401. And the slurry containing an abrasive | polishing material is discharged toward the cut end surface of the laminated | stacked panel part 10a, and the cut end surface of the laminated | stacked panel part 10a is brush-polished. As the abrasive, cerium oxide, zirconia, or the like is used. The average particle diameter (D50) of the abrasive is, for example, 5 μm or less, preferably 2 μm or less.

The brush 400 is a channel brush, and is formed by spirally winding a long member (channel) in which a plurality of brush hairs 402 are planted around a rotation shaft 401. The brush bristles 402 are mainly composed of a resin such as polyamide, and may include an abrasive such as alumina (Al ₂ O ₃ ), silicon carbide (SiC), or diamond. The bristle 402 may be formed in a linear shape and have a tapered tip.

Finally, as shown in step ST4 of FIG. 1, the adhesive layer 11 in the laminated panel portion 10a is removed, and a plurality of tempered glass panels can be obtained.
As described above, energy use efficiency and productivity are dramatically improved by the method for manufacturing a tempered glass panel according to the present embodiment.

  4A and 4B, a tempered glass plate 500 larger than the tempered glass plate 10 is laminated with the adhesive layer 11, and this is laser-cut along the cutting line 303, so that FIGS. 2A and 2B are obtained. The laminated tempered glass plate 10 shown can also be obtained. Here, FIG. 4A is a plan view showing a state in which the tempered glass plate 500 larger than the tempered glass plate 10 is laminated by the adhesive layer 11. FIG. 4B is a cross-sectional view showing a state in which the tempered glass plate 500 larger than the tempered glass plate 10 is laminated with the adhesive layer 11. In this way, the number of subsequent cuts can be reduced by laminating with the adhesive layer 11 at the stage of the tempered glass plate 500 that is larger than the tempered glass plate 10 from which the panel portion 10a is cut out. Can be improved.

  Next, with reference to FIGS. 5-9, the cutting method of a tempered glass board is demonstrated. FIG. 5 is a perspective view for explaining a method of cutting a tempered glass sheet. As shown in FIG. 5, the surface 12 of the tempered glass plate 10 is irradiated with the laser light 20, and the irradiation region 22 of the laser light 20 is moved on the surface 12 of the tempered glass plate 10. Stress is applied to cut the tempered glass sheet 10.

  The tempered glass plate 10 is produced by, for example, an air cooling tempering method or a chemical tempering method. The kind of glass for reinforcement | strengthening is selected according to a use. For example, in the case of an automobile window glass, an architectural window glass, a glass substrate for PDP (Plasma Display Panel), and a cover glass, soda lime glass is used as the reinforcing glass.

  The air-cooling strengthening method rapidly cools the glass near the softening point from the front and back surfaces, and creates a temperature difference between the front and back surfaces of the glass and the inside, so that the surface layer and the back surface layer where compressive stress remains are formed. Form. The air cooling strengthening method is suitable for strengthening thick glass.

  In the chemical strengthening method, the front and back surfaces of glass are ion-exchanged, and ions having a small ion radius (for example, Li ions and Na ions) contained in the glass are replaced with ions having a large ion radius (for example, K ions). Thus, the front surface layer and the back surface layer in which the compressive stress remains are formed. The chemical strengthening method is suitable for strengthening soda lime glass containing an alkali metal element.

  FIG. 6 is a cross-sectional view of the tempered glass plate before irradiation with laser light. In FIG. 6, the direction of the arrow indicates the acting direction of the residual stress, and the size of the arrow indicates the magnitude of the stress. As shown in FIG. 6, the tempered glass plate 10 includes a surface layer 13 and a back surface layer 15, and an intermediate layer 17 provided between the surface layer 13 and the back surface layer 15. Compressive stress remains on the front surface layer 13 and the back surface layer 15 by the air cooling strengthening method or the chemical strengthening method. Further, as a reaction, tensile stress remains in the intermediate layer 17.

FIG. 7 is a schematic diagram showing a distribution of residual stress of the tempered glass plate before irradiation with laser light.
As shown in FIG. 7, the compressive stress (> 0) remaining on the front surface layer 13 and the back surface layer 15 tends to gradually decrease from the front surface 12 and the back surface 14 of the tempered glass plate 10 toward the inside. Further, the tensile stress (> 0) remaining in the intermediate layer 17 tends to gradually decrease from the inside of the glass toward the front surface 12 and the back surface 14.

In FIG. 7, CS is the maximum residual compressive stress (surface compressive stress) (> 0) in the surface layer 13 and the back layer 15, and CT is the internal residual tensile stress in the intermediate layer 17 (average value of residual tensile stress in the intermediate layer 17). (> 0) and DOL indicate the thicknesses of the surface layer 13 and the back surface layer 15, respectively. CS, CT, and DOL can be adjusted by the strengthening process conditions. For example, CS, CT, and DOL can be adjusted by the cooling rate of the glass in the case of the wind-cooling down method. In addition, CS, CT, and DOL are ion-exchanged by immersing glass in a treatment liquid (for example, KNO ₃ molten salt) in the case of chemical strengthening, and can be adjusted by the concentration, temperature, immersion time, etc. of the treatment liquid. is there. The front surface layer 13 and the back surface layer 15 of the present embodiment have the same thickness and the same maximum residual compressive stress, but may have different thicknesses or different maximum residual compressive stresses. Good.

  An initial crack is formed in advance at the cutting start position at the end of the tempered glass plate 10. The method for forming the initial crack may be a general method, for example, a cutter, a file, or a laser. As described above, in the internal heating cutting using a laser or plasma, it is not necessary to form a scribe line (groove line) along the planned cutting line on the surface 12 of the tempered glass plate 10.

  On the surface 12 of the tempered glass plate 10, the irradiation region 22 of the laser light 20 is moved in a straight line shape or a curved shape along the planned cutting line from the end of the tempered glass plate 10 to the inside. Thereby, the crack 30 (refer FIG. 5) is extended toward the inner side from the edge part of the tempered glass board 10, and the tempered glass board 10 is cut | disconnected.

  In order to move the irradiation region 22 of the laser light 20 on the surface 12 of the tempered glass plate 10, the holder supporting the tempered glass plate 10 may be moved or rotated, or the light source of the laser light 20 is moved. May be. Further, a mirror provided in the middle of the path of the laser beam 20 may be rotated.

  On the surface 12 of the tempered glass plate 10, the irradiation region 22 of the laser beam 20 is formed in a circular shape as shown in FIG. 5, for example. There is no limit.

  On the surface 12 of the tempered glass plate 10, the irradiation region 22 of the laser beam 20 is the thickness of the tempered glass plate 10, the maximum residual compressive stress (CS), the internal residual tensile stress (CT), the surface layer 13 and the back surface layer 15. Is moved at a speed corresponding to the thickness (DOL) of the laser beam, the output of the light source of the laser beam 20, and the like.

  The light source of the laser light 20 is not particularly limited. For example, a UV laser (wavelength: 355 nm), a green laser (wavelength: 532 nm), a semiconductor laser (wavelength: 808 nm, 940 nm, 975 nm), a fiber laser (wavelength: 1060 to 6060). 1100 nm), YAG laser (wavelengths: 1064 nm, 2080 nm, 2940 nm) and the like. There is no limitation on the oscillation method of the laser beam 20, and either a CW laser that continuously oscillates the laser beam or a pulse laser that intermittently oscillates the laser beam can be used. The intensity distribution of the laser beam 20 is not limited, and may be a Gaussian type or a top hat type.

  The laser light 20 emitted from the light source is collected by a condenser lens or the like and imaged on the surface 12 of the tempered glass plate 10. The condensing position of the laser light 20 may be on the laser light source side or the back surface 14 side with respect to the front surface 12 of the tempered glass plate 10. Further, the condensing position of the laser beam 20 may be in the tempered glass plate 10 as long as the heating temperature does not become too high, that is, the condensing area can keep the annealing point or less.

  The optical axis of the laser beam 20 may be orthogonal to the surface 12 as shown in FIG. 5 on the surface 12 of the tempered glass plate 10, or may intersect the surface 12 at an angle.

In the cutting method according to the present embodiment, when the absorption coefficient of the tempered glass plate 10 with respect to the laser beam 20 is α (cm ⁻¹ ) and the thickness of the tempered glass plate 10 is t (cm), 0 <α × It is made to satisfy t ≦ 3.0. Under this condition, by heating the intermediate layer 17 in the irradiation region 22 of the laser light 20 at a temperature equal to or lower than the annealing point, the extension of the crack 30 generated in the tempered glass plate 10 by the residual tensile stress of the intermediate layer 17 is controlled. The tempered glass plate 10 can be cut by the crack 30 due to the residual tensile stress. The intermediate layer 17 is heated at a temperature below the annealing point because when the heating is performed above the annealing point, the glass becomes high temperature and a viscous flow easily occurs even in a short time during which the laser beam passes. This is because the compressive stress generated by the laser beam is relieved by this viscous flow.

Assuming that the intensity of the laser beam 20 before entering the tempered glass plate 10 is I ₀ and the intensity of the laser beam 20 when moved through the tempered glass plate 10 by a distance L (cm) is I, I = I ₀ × The expression exp (−α × L) holds. This equation is called Lambert-Beer's law.
By setting 0 <α × t ≦ 3.0, the laser beam 20 reaches the inside without being absorbed by the surface of the tempered glass plate 10, so the inside of the tempered glass plate 10 is sufficiently heated. it can. As a result, the stress generated in the tempered glass plate 10 changes from the state shown in FIG. 6 to the state shown in FIGS.

  FIG. 8 is a cross-sectional view taken along line AA in FIG. 5 and includes a laser light irradiation region. 9 is a cross-sectional view taken along the line BB in FIG. 5, and is a rear cross section from the cross section shown in FIG. Here, “rear” means the rear of the laser beam 20 in the scanning direction. 8 and 9, the direction of the arrow indicates the direction of the applied stress, and the length of the arrow indicates the magnitude of the stress.

In the intermediate layer 17 in the irradiation region 22 of the laser beam 20, since the intensity of the laser beam 20 is sufficiently high, the temperature is higher than that of the surrounding area, and the tensile stress or compressive stress smaller than the residual tensile stress shown in FIG. Occurs. In a portion where a tensile stress smaller than the residual tensile stress or a compressive stress is generated, extension of the crack 30 is suppressed. In order to reliably suppress the extension of the crack 30, it is preferable that a compressive stress is generated in the intermediate layer 17, as shown in FIG.
In addition, since the compressive stress larger than the residual compressive stress shown in FIG. 6 has arisen in the surface layer 13 and the back surface layer 15 in the irradiation region 22 of the laser beam 20, the extension of the crack 30 is suppressed.

  In order to balance with the compressive stress shown in FIG. 8, tensile stress is generated in the intermediate layer 17 in the cross section behind the cross section shown in FIG. 8, as shown in FIG. 9. This tensile stress is larger than the residual tensile stress shown in FIG. 6, and a crack 30 is formed in a portion where the tensile stress reaches a predetermined value. The crack 30 penetrates from the front surface 12 to the rear surface 14 of the tempered glass plate 10 and is a so-called full cut cutting.

  If the irradiation region 22 of the laser beam 20 is moved in this state, the position of the irradiation region 22 has the stress distribution as shown in FIG. The tip position of the crack 30 moves so as to follow the position of the irradiation region 22 without moving off the planned cutting line. Therefore, the extension of the crack 30 can be controlled by the laser beam 20.

  Thus, by setting 0 <α × t ≦ 3.0, the extension of the crack 30 can be controlled by the laser light 20 in the tempered glass plate 10. And since the crack 30 extends just after the irradiation area | region 22, since a cutting line is formed according to the movement locus | trajectory of the irradiation area | region 22, a cutting | disconnection precision can be improved. Note that the tip of the crack 30 may follow the irradiation region 22 instead of following the irradiation region 22. The closer the tip of the crack 30 is to the irradiation region 22, or the more it overlaps, the cutting accuracy is further improved.

  Since high transparency is required for glass depending on the application, α × t is preferably closer to 0 when the laser wavelength used is close to the wavelength region of visible light. However, if α × t is too small, the absorption efficiency is deteriorated. Therefore, it is preferably 0.0005 or more (laser light absorption rate 0.05% or more), more preferably 0.002 or more (laser light absorption rate 0.2). % Or more), more preferably 0.004 or more (laser light absorption rate 0.4% or more).

  Glass, on the other hand, requires low transparency, so that when the used laser wavelength is close to the wavelength region of visible light, the larger α × t is better. However, if .alpha..times.t is too large, the surface absorption of the laser beam becomes large, and crack extension cannot be controlled. Therefore, α × t is preferably 3.0 or less (laser light absorptivity 95% or less), more preferably 0.1 or less (laser light absorptivity 10% or less), and further preferably 0.02 or less (laser Light absorption rate is 2% or less).

  By the way, when the internal residual tensile stress (CT) of the intermediate layer 17 is 30 MPa or more, only the residual tensile stress of the intermediate layer 17 allows the cracks formed in the tempered glass plate 10 to naturally extend (self-run). I know. Therefore, the internal residual tensile stress (CT) is 15 MPa or more so that the residual tensile stress of the intermediate layer 17 is more dominant than the tensile stress generated by the laser light 20 among the tensile stresses used for cutting. Preferably there is. As a result, the position within the tempered glass plate 10 where the tensile stress reaches a predetermined value, that is, the distance between the tip position of the crack 30 and the position of the laser beam 20 is sufficiently shortened, so that the cutting accuracy is improved. it can.

  The internal residual tensile stress (CT) of the intermediate layer 17 is more preferably 30 MPa or more, and further preferably 40 MPa or more. When the internal residual tensile stress (CT) is 30 MPa or more, the tensile stress used for cutting is only the residual tensile stress of the intermediate layer 17, and the trajectory accuracy of the cutting line can be further improved.

The absorption coefficient (α) is determined by the wavelength of the laser light 20, the glass composition of the tempered glass plate 10, and the like. For example, the content of iron oxide (including FeO, Fe ₂ O ₃ and Fe ₃ O ₄ ) in the tempered glass plate 10, the content of cobalt oxide (including CoO, Co ₂ O ₃ and Co ₃ O ₄ ), As the content of copper oxide (including CuO and Cu ₂ O) increases, the absorption coefficient (α) in the near-infrared wavelength region near 1000 nm increases. Furthermore, the absorption coefficient (α) increases in the vicinity of the absorption wavelength of the rare earth atom as the content of the oxide of the rare earth element (for example, Yb) in the tempered glass plate 10 increases.

The absorption coefficient (α) in the near-infrared wavelength region near 1000 nm is set according to the application. For example, in the case of window glass for automobiles, the absorption coefficient (α) is preferably 3 cm ⁻¹ or less. In the case of building window glass, the absorption coefficient (α) is preferably 0.6 cm ⁻¹ or less. In the case of display glass, the absorption coefficient (α) is preferably 0.2 cm ⁻¹ or less.

  The wavelength of the laser beam 20 is preferably 250 to 5000 nm. By setting the wavelength of the laser beam 20 to 250 to 5000 nm, both the transmittance of the laser beam 20 and the heating efficiency by the laser beam 20 can be achieved. The wavelength of the laser beam 20 is more preferably 300 to 4000 nm, still more preferably 800 to 3000 nm.

  The content of iron oxide in the tempered glass plate 10 depends on the type of glass constituting the tempered glass plate 10, but in the case of soda lime glass, it is, for example, 0.02 to 1.0% by mass. By adjusting the content of iron oxide in this range, α × t in the near infrared wavelength region near 1000 nm can be adjusted to a desired range. Instead of adjusting the content of iron oxide, the content of cobalt oxide, copper oxide, or rare earth element oxide may be adjusted.

  Although the thickness (t) of the tempered glass board 10 is set according to a use, it is preferable that it is 0.01-0.2 cm. In the case of chemically strengthened glass, the internal residual tensile stress (CT) can be sufficiently increased by setting the thickness (t) to 0.2 cm or less. On the other hand, when the thickness (t) is less than 0.01 cm, it is difficult to subject the glass to chemical strengthening treatment. The thickness (t) is more preferably 0.03 to 0.15 cm, still more preferably 0.05 to 0.15 cm.

  Note that the present invention is not limited to the above-described embodiment, and can be changed as appropriate without departing from the spirit of the present invention. For example, the present invention is applicable not only to cutting with a laser beam but also to internally cutting a tempered glass plate.

DESCRIPTION OF SYMBOLS 10 Tempered glass board 10a Panel part 10b Peripheral part 11 Adhesive layer 12 Front surface 13 Surface layer 14 Back surface 15 Back surface layer 17 Intermediate layer 20 Laser beam 22 Irradiation area 30 Crack 101 Vacuum adsorption table 301, 303 Cutting line 302, 302a, 302b Auxiliary cutting Line 500 Tempered glass plate

Claims (6)

Bonding the main surfaces of a plurality of tempered glass plates with an adhesive layer and laminating them in the thickness direction;
Cutting the laminated tempered glass panels from the laminated tempered glass plates by internal heating cutting; and
Removing the adhesive layer from the laminated plurality of tempered glass panels. A method for producing a tempered glass panel.   The method for producing a tempered glass panel according to claim 1, further comprising a step of polishing end surfaces of the laminated tempered glass panels laminated before the step of removing the adhesive layer.   The method for producing a tempered glass panel according to claim 1, wherein the internal heating cutting is cutting with a laser beam.   The method for producing a tempered glass panel according to claim 3, wherein the light source of the laser light is a fiber laser.   5. The method for producing a tempered glass panel according to claim 3, wherein the adhesive layer is not formed at a position where the plurality of laminated tempered glass plates are cut by the laser beam. 6.   The method for producing a tempered glass panel according to any one of claims 3 to 5, wherein the laser light absorption rate of each of the laminated tempered glass plates is less than 10%. .

Images