Method for manufacturing glass product

Abstract

To cut a glass film laminate so as to easily peel a glass film from a support glass.SOLUTION: A method for manufacturing a glass product comprises a cutting step S3 of cutting a glass film laminate 3 by irradiating the glass film laminate with a laser beam L. In the cutting step S3, the focus depth DOF of the laser beam L is set to a value larger than the thickness T of the glass film laminate 3 and in the cutting step S3, the entire glass film laminate 3 in the thickness direction is positioned within the focus depth DOF of the laser beam L at an irradiation position of the glass film laminate 3 with the laser beam L.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a method for producing a glass product. [Background technology]

[0002] In recent years, there has been an increasing demand for thinner and lighter mobile terminals, such as smartphones and tablet terminals, which have become increasingly popular. Accordingly, there has also been an increasing demand for thinner glass substrates used in these mobile terminals.

[0003] Under these circumstances, the development of ultra-thin glass sheets that have been thinned to the point of being like a film has progressed, and for example, glass sheets with a thickness of 300 μm or less have been manufactured. Ultra-thin glass sheets are generally called glass films, and because they are extremely thin, they have the property of being highly flexible.

[0004] The surface of the glass film is subjected to a process related to the manufacture of electronic devices, which involves heating for performing a film formation process, such as forming a transparent conductive film of ITO or the like. In this case, in order to facilitate handling of the highly flexible glass film, a glass film laminate is used in which a glass film is laminated on the surface of a supporting glass (see, for example, Patent Document 1).

[0005] By using the glass film laminate, it becomes possible to easily perform positioning, transportation, and the like of the glass film when performing manufacturing-related processes for electronic devices. By performing the manufacturing-related processes, an electronic device is formed on the glass film, and a glass substrate composed of the glass film and the electronic device is manufactured. Thereafter, the glass substrate is peeled off from the supporting glass to be manufactured as a product. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2011-162432 A Summary of the Invention [Problem to be solved by the invention]

[0007] Incidentally, after a process related to the manufacture of an electronic device has been performed, a glass film laminate may be cut. As a cutting method, a method of fracturing or melting the glass film laminate by irradiating it with laser light is used.

[0008] However, when cutting the glass film laminate, the adhesion between the glass film and the supporting glass increases due to heating by the laser light, and it may become difficult to peel the glass film from the supporting glass in some cases. In this case, the glass film needs to be peeled off from the supporting glass after cutting off the part with increased adhesion with a tool such as a diamond tip, which makes the peeling process complicated.

[0009] The present invention has been made in view of the above circumstances, and has an object to cut a glass film laminate so that the glass film can be easily peeled off from a supporting glass. [Means for solving the problem]

[0010] (1) The present invention is intended to solve the above-mentioned problems, and is characterized in that in a manufacturing method of a glass product, the method includes a cutting step of cutting a glass film laminate by irradiating laser light, the glass film laminate includes a glass film and a supporting glass supporting the glass film, and in the cutting step, a focal depth of the laser light is set to be larger than a thickness of the glass film laminate, and in the cutting step, at a position where the laser light is irradiated onto the glass film laminate, the entire glass film laminate in the thickness direction is located within a range of the focal depth of the laser light.

[0011] According to this configuration, the focal depth of the laser light is set to be greater than the thickness of the glass film laminate, and the entire glass sheet laminate in the thickness direction is located within the range of the focal depth, thereby making it possible to prevent the irradiated portion of the glass film laminate to be heated to a high temperature, thereby making it possible to cut the glass film laminate so that the glass film can be easily peeled off from the supporting glass.

[0012] (2) In the method for producing a glass product described above in (1), the laser light may be a pulsed laser light, and the pulse width of the laser light may be not less than 1 fs and not more than 100 ps.

[0013] (3) In the method for producing a glass product according to (1) or (2) above, the laser light may be an IR laser light.

[0014] (4) In the method for producing a glass product according to any one of the above (1) to (3), the thickness of the glass film laminate may be 0.1 mm or more and 2.0 mm or less.

[0015] (5) In the method for producing a glass product according to any one of the above (1) to (4), the glass film laminate may include the glass film having a thickness of 30 μm or more and 200 μm or less.

[0016] (6) In the method for producing a glass product according to any one of (1) to (5) above, the laser light may be focused by an axicon lens. Effect of the Invention

[0017] According to the present invention, the glass film laminate can be cut so that the glass film can be easily peeled off from the supporting glass. [Brief description of the drawings]

[0018] [Figure 1] 1 is a flow chart showing a method for manufacturing a glass product. [Diagram 2] FIG. [Diagram 3] FIG. [Figure 4] FIG. [Diagram 5] FIG. 2 is a plan view of a glass film laminate. [Figure 6] FIG. 4 is a cross-sectional view of the glass film laminate illustrating a cutting step. [Figure 7] FIG. 1 is a diagram for explaining an axicon lens. [Figure 8] FIG. [Figure 9] FIG. 4 is a side view of the glass film laminate after a cutting step. [Figure 10] FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0019] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Figures 1 to 10 show an embodiment of a method for manufacturing a glass product according to the present invention.

[0020] As shown in FIG. 1, the method includes a lamination step S1, a processing step S2, a cutting step S3, and a peeling step S4.

[0021] The lamination step S1 is a step of producing a glass film laminate 3 including a glass film 1 and a supporting glass 2 supporting the glass film 1. As shown in Fig. 2, one surface of the glass film 1 and one surface of the supporting glass 2 are opposed to each other, and the glass film 1 is laminated on the supporting glass 2. The surface of the glass film 1 and the surface of the supporting glass 2 are brought into close contact with each other, thereby producing the glass film laminate 3.

[0022] The glass film 1 is composed of a rectangular transparent glass film. The thickness of the glass film 1 is preferably 30 μm or more and 200 μm or less, and more preferably 50 μm or more and 100 μm or less.

[0023] The supporting glass 2 is composed of a rectangular transparent glass plate. The supporting glass 2 has a larger area than the glass film 1. As a result, when the glass film 1 is laminated on the supporting glass 2, the end 2a of the supporting glass 2 is located outside the end 1a of the glass film 1. As a result, the end 1a of the glass film 1 is protected by the supporting glass 2.

[0024] The difference in thermal expansion coefficient between the supporting glass 2 and the glass film 1 at 30 to 380°C is 5 × 10 -7 / ° C. is preferably used. This makes it possible to obtain the glass film laminate 3 that is unlikely to suffer from thermal warping or the like due to the difference in expansion coefficient and can maintain a stable laminated state even if a heat treatment is performed in the treatment step S2 after the lamination step S1.

[0025] In consideration of the handleability of the glass film laminate 3, the thickness of the supporting glass 2 is preferably 400 μm or more and 700 μm or less, and more preferably 500 μm or more and 700 μm or less.

[0026] The glass film 1 and the supporting glass 2 are preferably formed by, for example, an overflow downdraw method.

[0027] In the overflow downdraw method, for example, molten glass is poured into an overflow groove provided on the upper part of a forming body having a substantially wedge-shaped cross section, and the molten glass overflowing from the overflow groove is allowed to flow down along both side surfaces of the forming body while being fused and integrated at the lower end of the forming body, thereby continuously forming a glass ribbon.

[0028] Thereafter, the glass ribbon is subjected to an annealing process and cut to a desired length to form a sheet-shaped mother glass film or mother glass plate. The glass film 1 and the supporting glass 2 can be produced by cutting the mother glass film and the mother glass plate to a predetermined size.

[0029] The glass film 1 and the supporting glass 2 are, for example, made of silicate glass or silica glass, and are preferably made of borosilicate glass, soda-lime glass, aluminosilicate glass, or alkali-free glass. Here, the alkali-free glass refers to glass that does not substantially contain an alkali component (alkali metal oxide), and specifically refers to glass having an alkali component weight ratio of 3000 ppm or less. The alkali component weight ratio in the present invention is preferably 1000 ppm or less, more preferably 500 ppm or less, and most preferably 300 ppm or less.

[0030] The surface roughness Ra of the glass film 1 and the supporting glass 2 is preferably 2.0 nm or less, more preferably 1.0 nm or less, further preferably 0.5 nm or less, and most preferably 0.2 nm or less. This increases the bonding area per unit area of ​​the glass film 1 and the supporting glass 2, thereby improving adhesion. Therefore, the glass film 1 and the supporting glass 2 can be firmly bonded to each other without using an adhesive.

[0031] The following describes the adhesion caused by surface contact between the glass film 1 and the supporting glass 2. When one surface of the glass film 1 and one surface of the supporting glass 2 are brought into surface contact with each other, the surface roughness Ra of each surface is set to 2.0 nm or less, so that one surface is slightly positively charged and the other surface is slightly negatively charged, which is believed to result in a phenomenon in which the two surfaces attract each other (so-called hydrogen bonding).

[0032] The processing step S2 is a step of forming an electronic device material 4 on the glass film 1 to manufacture a glass substrate 5. As shown in Fig. 3, in the processing step S2, the electronic device material 4 is formed on the glass film 1 of the glass film laminate 3 produced in the lamination step S1. In this way, a glass substrate 5 having the electronic device material 4 and the glass film 1 is formed. The thickness T of the glass film laminate 3 including the glass substrate 5 is preferably 0.1 mm or more and 2.0 mm or less, and more preferably 0.5 mm or more and 1.0 mm or less.

[0033] Examples of the electronic device material 4 formed on the glass film 1 include liquid crystal elements, organic EL elements, touch panel elements, solar cell elements, piezoelectric elements, light receiving elements, battery elements such as lithium ion secondary batteries, MEMS elements, and semiconductor elements.

[0034] 3 , the area of ​​the electronic device member 4 formed on the glass film 1 is smaller than the area of ​​the glass film 1. Therefore, the end 1a of the glass film 1 protrudes outward more than the end 4a of the electronic device member 4. As a result, the end 4a of the electronic device member 4 is protected by the glass film 1.

[0035] In the cutting step S3, the glass film laminate 3 is cut by a laser light irradiation device 6 that irradiates laser light L. The laser light irradiation device 6 is disposed above the glass film laminate 3 and configured to be movable in the vertical and horizontal directions. In the cutting step S3 according to the present embodiment, a case will be described in which the laser light L is irradiated from the glass film 1 side of the glass film laminate 3, but this is not limiting, and the laser light L may be irradiated from the supporting glass 2 side. Furthermore, after the laser light L is irradiated, an external force may be applied to the glass film laminate 3 to promote cutting.

[0036] The laser light L irradiated by the laser light irradiating device 6 is preferably an IR laser light, but is not limited thereto and other laser lights may be used. As the laser light L, for example, a pulsed laser light is used.

[0037] The pulse width of the laser light L is preferably 1 fs or more and 100 ps or less, and more preferably 10 fs or more and 50 ps or less. The pulse energy of the laser light L from the laser light irradiation device 6 is preferably 1 μJ or more and 300 μJ or less, and more preferably 5 μJ or more and 200 μJ or less. The wavelength of the laser light L is preferably 200 nm or more and 3000 nm or less, and more preferably 250 nm or more and 1500 nm or less.

[0038] As shown in Fig. 4, in the cutting step S3, a laser beam L is irradiated to a position that is outside an end 4a of an electronic device material 4 and inside an end 1a of a glass film 1. The laser beam irradiator 6 moves in a predetermined direction to scan the laser beam L along a predetermined planned cutting line CL shown in Fig. 5. The scanning speed of the laser beam L is preferably 10 mm / s or more and 5000 mm / s or less.

[0039] 6, in the cutting step S3, the focal depth DOF of the laser light L is set to be larger than the thickness T of the glass film laminate 3. Furthermore, in the cutting step S3, at the irradiation position of the laser light L on the glass film laminate 3, the entire glass film laminate 3 in the thickness direction is located within the range of the focal depth DOF of the laser light L. This makes it possible to uniformly irradiate the entire range of the glass film laminate 3 in the thickness direction with the laser light L.

[0040] In the above case, it is preferable that the focal depth DOF of the laser light L is 500 μm or more. Also, it is preferable that the spot diameter of the laser light L is 0.1 μm or more and 20 μm or less.

[0041] The laser light L is preferably focused by, for example, an axicon lens.

[0042] As shown in Figure 7, the axicon lens AX is a cone-shaped prism defined by the alpha angle (α angle) and the apex angle. Unlike focusing lenses such as plano-convex lenses, biconvex lenses, and aspheric lenses that focus light from a light source around the optical axis, the axicon lens AX focuses the light in a line shape to multiple points around the optical axis. The axicon lens AX does not diffract laser light, and the intensity distribution does not change even if the light propagates far. Therefore, the axicon lens AX is similar to a Bessel beam with almost no diffraction within its depth of focus (DOF). The magnitude of the depth of focus DOF ​​is a function of the radius R of the beam incident on the axicon lens AX, the refractive index n of the axicon lens AX, and the α angle, and is expressed by the following equation.

[0043] DOF=R / {(n-1)α}

[0044] As shown in FIG. 8, in the cutting step S3, the focal depth DOF of the laser light L can be easily set to be larger than the thickness T of the glass film laminate 3 by using the axicon lens AX.

[0045] In the cutting process S3, a modified region is formed in the region irradiated with the laser light L by multiphoton absorption of the laser light L. The glass film laminate 3 is cut as a result of the formation of a large number of microcracks in this modified region. The modified region is generated simultaneously throughout the entire thickness direction of the glass film laminate 3 at the position irradiated with the laser light L. As a result, both the glass film 1 and the supporting glass 2 are cut simultaneously at the site irradiated with the laser light L.

[0046] As shown in FIG. 9, when the cutting step S3 is completed, a glass film laminate 3 in which the end 1a of the glass film 1 and the end 2a of the supporting glass 2 coincide with each other is produced.

[0047] The peeling step S4 is a step of peeling the glass substrate 5 from the supporting glass 2. As shown in Fig. 10, in the peeling step S4, a plurality of suction pads 7 are used to peel the glass substrate 5 from the supporting glass 2.

[0048] Each suction pad 7 has a plurality of suction holes at the portion where it comes into contact with the glass substrate 5. Each suction pad 7 generates a negative pressure on the glass substrate 5 through these suction holes, thereby suctioning the glass substrate 5. Each suction pad 7 that has suctioned the glass substrate 5 moves upward in sequence from the end side of the glass substrate 5, thereby peeling off the entire glass substrate 5 from the supporting glass 2. Through the above steps S1 to S4, the glass substrate 5 is manufactured as a glass product.

[0049] According to the manufacturing method of the glass product (glass substrate 5) according to the present embodiment described above, the focal depth DOF of the laser light L is set to be greater than the thickness T of the glass film laminate 3, and the entire glass plate in the thickness direction is positioned within the range of this focal depth DOF, so that the portion of the glass film laminate 3 irradiated with the laser light L is not heated to a high temperature, and the glass film laminate 3 can be cut.

[0050] This makes it possible to prevent an increase in the adhesion between the glass film 1 and the supporting glass 2, which occurs when the site irradiated with the laser light L is heated to a high temperature as in the conventional cutting method. Therefore, in the peeling step S4 after the cutting step S3, the glass substrate 5 (glass film 1) can be easily peeled off from the supporting glass 2.

[0051] The present invention is not limited to the configuration of the above embodiment, nor is it limited to the above-mentioned effects and advantages. Various modifications of the present invention are possible without departing from the spirit and scope of the present invention.

[0052] In the above embodiment, the rectangular glass film laminate 3 is produced by laminating the rectangular glass film 1 and the supporting glass 2, but the present invention is not limited to this configuration. The glass film 1 and the supporting glass 2 may be circular or have another shape, or may have different shapes from each other.

[0053] In the above embodiment, the method for manufacturing the glass film laminate 3 in which the cutting step S3 is performed after the processing step S2 is illustrated, but the present invention is not limited to this configuration. The cutting step S3 may be performed after the laminating step S1 and before the processing step S2. In other words, the present invention can also be applied to the case where the glass film laminate 3 is cut before the electronic device material 4 is formed on the glass film 1.

[0054] In the above embodiment, in the cutting step S3, the laser light L is irradiated to a position away from the electronic device material 4 and where the glass film 1 and the supporting glass 2 are laminated, but the present invention is not limited to this embodiment. In the cutting step S3, the laser light L may be irradiated to a position where the electronic device material 4 is formed, as long as the function of the electronic device material 4 is not impaired.

[0055] In the above embodiment, the case of cutting the glass film laminate 3 formed by stacking two pieces of glass, the glass film 1 and the supporting glass 2, has been described as an example, but the present invention is not limited to this embodiment. The present invention is also applicable to the case of cutting the glass film laminate 3 formed by stacking three or more pieces of glass films or glass plates.

[0056] In the present invention, the glass product is not limited to a glass substrate 5 on which an electronic device material 4 is formed, but also includes a glass film laminate in which a glass film 1 and a supporting glass 2 are laminated, and a glass film laminate in which a glass substrate 5 and a supporting glass 2 are laminated. EXAMPLES

[0057] Examples of the present invention will be described below, but the present invention is not limited to these examples.

[0058] The present inventors conducted a test to confirm the effects of the present invention. In this test, a laminate formed by laminating a glass film and a supporting glass was cut by irradiation with a laser beam, and the adhesive strength and peelability between the glass film and the supporting glass were confirmed.

[0059] In the test, for the examples and comparative examples, a glass film laminate was cut using a pulsed laser of IR laser light or CO2 laser light. The pulse width of the pulsed laser was 13 ps. The pulse energy of the laser light was 100 μJ. The wavelength of the IR laser light was 1064 nm, and the wavelength of the CO2 laser light was 10.6 μm. The scanning speed of the laser light was 200 mm / s.

[0060] For Examples 1 and 2 having different glass film thicknesses, the focal depth of the laser light was set to be greater than the thickness of the glass film laminate, and the glass film laminate was irradiated with the laser light such that the entire glass film laminate in the thickness direction was positioned within the focal depth of the laser light.

[0061] On the other hand, in Comparative Example 1 and Comparative Example 2, the focal depth of the laser light was set to be smaller than the thickness of the glass film laminate, and the glass film laminate was irradiated with the laser light such that the glass film laminate protruded beyond the focal depth of the laser light.

[0062] After cutting the glass film laminate for each example, the adhesive strength between the glass film and the supporting glass was measured for the end of the glass film laminate formed by cutting (the area irradiated with laser light) and a part away from the end that was not irradiated with laser light (the non-irradiated area with laser light).

[0063] The adhesive strength between the glass film and the supporting glass was measured by a crack opening method. Based on the measured adhesive strength, the peelability between the glass film and the supporting glass was evaluated. In this evaluation, if peelable, it was rated as "○" (good), and if not peelable, it was rated as "×" (bad). In addition, regarding the quality of cuttability, if cuttable, it was rated as "○" (good), and if not cuttable, it was rated as "×" (bad).

[0064] The test conditions and results are shown in Table 1. [Table 1]

[0065] As shown in Table 1, in Examples 1 and 2, even after cutting by irradiation with laser light, the adhesive strength between the glass film and the supporting glass in the irradiated area with laser light did not change significantly, and good peelability was demonstrated.

[0066] In contrast, the glass film laminate could not be cut by irradiation with laser light in Comparative Example 1. In addition, in Comparative Example 2, the adhesive strength in the irradiated area with laser light was significantly greater than the adhesive strength in the non-irradiated area, and peelability was deteriorated. [Explanation of symbols]

[0067] 1 Glass film 2 Support glass 3. Glass film laminate 5. Glass substrates (glass products) AX Axicon Lens DOF depth of focus L Laser light S3 cutting process T Glass film laminate thickness

Claims

1. A method for manufacturing a glass product, comprising a cutting step of cutting a glass film laminate by irradiating a laser beam, The glass film laminate includes a glass film and a supporting glass that supports the glass film, In the cutting step, a focal depth of the laser light is set to be larger than a thickness of the glass film laminate, a cutting step for cutting the glass film laminate by the laser beam from the laser beam irradiation position of the glass film laminate, the glass film laminate being entirely located within a range of the focal depth of the laser beam in a thickness direction of the glass film laminate;

2. the laser beam is a pulsed laser beam, 2. The method for producing a glass product according to claim 1, wherein the pulse width of the laser light is not less than 1 fs and not more than 100 ps.

3. 3. The method for manufacturing a glass product according to claim 1, wherein the laser light is an IR laser light.

4. The method for manufacturing a glass product according to claim 1 or 2, wherein the thickness of the glass film laminate is 0.1 mm or more and 2.0 mm or less.

5. The method for manufacturing a glass product according to claim 1 or 2, wherein the glass film laminate includes the glass film having a thickness of 30 μm or more and 200 μm or less.

6. 3. The method for producing a glass product according to claim 1, wherein the laser beam is focused by an axicon lens.

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