JP2015030661A - Method for breaking glass substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for breaking a glass substrate without causing a break line to be deviated and causing chipping or shark teeth to be generated on a break surface.SOLUTION: A break table 2 which holds a glass substrate 1 comprises a fixed table 21, and a rotary table 22 which adjoins the fixed table 21 via a predetermined gap and can be rotated around a predetermined rotary shaft 9, and a flexible soft resin film 3 is arranged across the fixed table 21 and the rotary table 22. The glass substrate 1 is supported on the soft resin film 3 so that one side of a scribe line 10 is positioned on the fixed table 21 and the other side thereof is positioned on the rotary table 22 so as to allow the scribe line 10 to be positioned on an upper surface and on a predetermined gap. The glass substrate 1 on the rotary table 22 side is rotated around the rotary shaft 9 together with the rotary table 22 while pressing both sides of the scribe line 10 of the glass substrate 11 by hard resin layers 5 and 7 having rigidity and flexibility.

Description

The present invention relates to a method for breaking glass for flat panel displays used in smartphones, tablet terminals, notebook computers, touch table screens, television screens, etc., and in particular heat treatment of aluminosilicate glass or float glass whose glass surface has been chemically strengthened. In addition, the present invention relates to a glass substrate break method suitable for breaking a substrate of glass (hereinafter, collectively referred to as high-strength glass) in which a tempered layer is formed on a surface such as air-cooled tempered glass.

Recently, in the cutting of glass substrates, a thermal stress scribing method (hereinafter abbreviated as laser scribing) using laser beam irradiation has come to be used in place of the diamond tip mechanical method that has been used for the past century. . According to laser scribing, defects inherent in the mechanical method, that is, a decrease in glass strength due to the occurrence of microcracks, contamination due to the occurrence of cullet at the time of cleaving, the presence of a lower limit value of the applied plate thickness, and the like can be eliminated.

In laser scribing, generally, glass is locally heated and irradiated with laser light to the extent that vaporization, melting, and cracks do not occur. At this time, the glass heating portion tries to expand thermally, but cannot sufficiently expand due to the reaction from the surrounding glass, and compressive stress is generated in this heating region. Even in the peripheral non-heated region, the peripheral portion is further distorted by the expansion from the heating portion, and as a result, compressive stress is generated. Such compressive stress is in the radial direction with the heating center point as the origin, and propagates throughout the glass plate almost at the speed of sound after heating occurs. When the object has a compressive stress, a tensile stress proportional to the Poisson's ratio is generated in the orthogonal direction.

If there is a crack at the position where the tensile stress is present, stress expansion occurs at the crack tip, and if the expanded stress exceeds the fracture toughness value of the material, the crack expands. That is, a controlled cleaving occurs in which the crack progresses from the crack tip toward the heating center. Therefore, the crack can be extended by scanning the laser irradiation point in advance.

Laser scribing of glass substrates uses this principle, and when cooling is performed near the maximum point of tensile stress, the tensile stress amplified by the shrinkage of the glass at this time is useful for strengthening the cleaving, and cleaving by combining heating and cooling. Has been proposed (see Patent Document 1).
According to Patent Document 1, CO2 laser light is used as the heating laser light. 99% of the energy in the beam spot of the CO2 laser light is absorbed in the glass surface layer having a depth of 3.7 μm on the glass plate 6 and is not transmitted over the entire thickness of the glass plate. This is due to the extremely large absorption coefficient of glass at the CO ₂ laser wavelength. As a result, heating occurs only in the surface layer of the glass plate, and compressive stress is generated in this heating region.

When cooling is performed at a cooling point located outside the heating region, tensile stress is generated, and surface scribes starting from the initial crack are generated behind the cooling point. The depth of this scribe is usually about 100 μm for soda glass or the like. However, the glass plate is highly brittle and it is easy to mechanically cleave it by applying a bending stress in accordance with this scribe line. The process of cleaving by applying the bending stress is referred to as “break”. The laser beam is scanned in the scanning direction. This method has many advantages compared with the conventional mechanical method, and has gradually been applied to the production of flat panel display devices.

The process of breaking by applying bending stress is to break the glass substrate on which the split is formed by holding both sides of the split of the glass substrate on the substrate holding member, and fixing one substrate holding member on one side of the substrate Fix to the table and attach the other board holding member to the slide table located on the other side of the board via the slide drive source, and center the slide table approximately under the board split and parallel to the crack. And a method of bending and cleaving the substrate along the split by swinging the slide table downward about the axis (see Patent Document 2), or cutting a glass substrate There have been proposed a method (Patent Document 3 and Patent Document 4) in which a desired position is protruded from a jig and fixed, and a break actuator is applied to a protruding portion of a glass substrate to be folded.

Japanese Patent No. 3027768 Japanese Patent Laid-Open No. 2002-18797 No. 2-4099 JP 2006-319846 A

On the other hand, in recent years, high-strength glass with chemically strengthened glass front and back surfaces has been utilized as glass for flat panel displays such as smartphones, tablet terminals, laptop computers, touch table screens and TV screens to increase the hardness of the glass surface. Has been. As such high-strength glass, for example, gorilla glass from Corning, IOX-FS glass, Dragon Trail glass from Asahi Glass (all are trade names), and the like are known.

The break methods according to Patent Documents 2 to 4 have no problem in break processing of a glass substrate with ordinary soda glass, but in the case of high-strength glass, the break line may be deviated from the scribe line, There is a problem that the quality of the glass substrate after the breakage is deteriorated, for example, chipping and shark teeth are generated and the glass strength is lowered.

The present invention solves such problems, and in break processing of a glass substrate, particularly a high-strength glass substrate, the break line does not deviate from the scribe line, and chipping and shark teeth do not occur on the break surface. Another object of the present invention is to provide a glass substrate break method that can realize mirror finishing.

In order to achieve the above object, according to the present invention, a break table that holds a glass substrate on which a scribe line is formed is fixed to a fixed table and a fixed table adjacent to the fixed table via a predetermined gap, and is rotatable around a predetermined rotation axis. A flexible soft resin film is arranged on the substrate holding table so as to span the fixed table and the rotary table, and the glass substrate is placed on the predetermined gap so that the scribe line is on the upper surface. The scribe line is supported on the soft resin film so that one side is on the fixed table and the other side is on the rotary table with the scribe line as a boundary. Is pressed with a hard resin layer having a certain degree of rigidity and a certain degree of flexibility, so that the glass substrate on the rotating table side is rotated. Along the scribe line of the glass substrate was allowed to proceed crack is to break the glass by rotating about an axis of rotation with Le.

According to the above configuration, in the break processing of the glass substrate, the break line does not deviate from the scribe line, and mirror surface processing can be realized with almost no chipping, shark teeth, cullet, etc. on the break surface. Especially when the break line of the glass substrate is broken, the break line is easily displaced from the scribe line, and when the break surface is a high-strength glass substrate where chipping, shark teeth, cullet, etc. are likely to occur, the break line is not displaced from the scribe line. Mirror surface processing with almost no chipping on the break surface, shark teeth, cullet, etc. can be realized.

According to the present invention, in break processing of a glass substrate, particularly a high-strength glass substrate, the break line does not deviate from the scribe line, and mirror surface processing can be performed without generating chipping, shark teeth, cullet, etc. on the break surface. realizable. In addition, even if the front and back surfaces of the high-strength glass substrate are somewhat uneven, there is a variation in the clamping force when the high-strength glass substrate is sandwiched between the soft resin film on the break table and the hard resin layer that presses the high-strength glass substrate. While being able to make small, the positioning precision with the hard resin layer which presses a scribe line and a high intensity | strength glass substrate can also be loosened.

The conceptual perspective view of the whole structure which concerns on the Example of the break apparatus for enforcing the break method of the glass substrate by this invention A-A 'line cross-sectional side view according to the embodiment of the break device in FIG. The top view which concerns on the Example of the break device in FIG. The side view which looked at the cross-section side view which concerns on the Example of the break device in FIG. 2 from the arrow X direction FIG. 2 is a cross-sectional side view taken along line A-A ′ immediately before the break according to the embodiment of the break device in FIG. 2. FIG. 5 is a cross-sectional side view taken along line A-A 'at the start of a break according to the embodiment of the break device in FIG. The side view which looked at the AA 'cross section side view at the time of the break start which concerns on the Example of the break device in FIG. 6 from the arrow X direction Sectional side view explaining the operation of the break device in FIG.

According to the present invention, a break table that holds a glass substrate on which a scribe line is formed is constituted by a fixed table and a rotary table that is adjacent to the fixed table via a predetermined gap and is rotatable around a predetermined rotation axis. A flexible soft resin film is arranged on the substrate holding table so as to straddle the table and the rotary table, and the scribe line is placed so that the scribe line is located on the upper surface and the glass substrate is on the predetermined gap. Supporting on the soft resin film so that one side is on the fixed table and the other side is on the rotary table at the boundary, the scribe line side of the glass substrate has a certain degree of rigidity on both sides of the scribe line, Moreover, it is pressed with a hard resin layer having a certain degree of flexibility, and the glass substrate on the rotary table side is rotated around the rotary shaft together with the rotary table. Along the scribe line of the glass substrate was allowed to proceed crack is to break the glass by rolling.

In addition, the present invention provides a break line scribe line even when a high-strength glass substrate that breaks easily from chipping, shark teeth, cullet, etc. on the break surface during break processing of a glass substrate. Mirror finish with almost no chipping on the break surface, shark teeth, cullet, etc. can be realized.

Further, when the soft resin film that supports the glass substrate is a soft urethane resin, the adhesiveness with the glass substrate is particularly high, and the action of buffering the breaking force that tears the glass when the glass substrate is broken is particularly excellent.

In addition, when a polytetrafluoroethylene layer is provided on the contact surface of the soft resin film with the glass substrate, the soft resin film and the glass substrate can be easily separated after the break.

In addition, by making the thickness of the soft resin film different according to the thickness of the glass substrate to be cleaved, it is necessary to closely adjust the amount of pressing force applied during the break operation even if the thickness of the glass substrate is different. Absent.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described with reference to the drawings. In the following examples, a high-strength glass substrate will be described as an example of a glass substrate, but it is needless to say that the present invention can also be carried out on a normal soda glass substrate.

FIG. 1 is a conceptual perspective view showing the overall configuration of an embodiment of a break device for carrying out a break method for a high-strength glass substrate according to the present invention, and FIG. 2 is an AA of an embodiment of the break device in FIG. 3 is a sectional side view, FIG. 3 is a plan view of the embodiment of the break device in FIG. 1, and FIG. 4 is a side view of the sectional side view in FIG.

A glass substrate 1 made of high-strength glass is placed on a break table 2 for holding the substrate. The glass substrate 1 is preliminarily formed with a scribe line 10 by laser scribe on one main surface, and the surface on which the scribe line 10 is formed becomes the upper surface side of the glass substrate 1, that is, the scribe line 10 breaks. It is placed in contact with the upper surface of the table 2. As shown in FIG. 2, the break table 2 is composed of a pair of table members arranged with a predetermined gap, and one table member is a fixed table 21 fixedly arranged when the glass substrate 1 is broken, and the other The table member constitutes a rotary table 22 that can rotate downward with respect to the plane of the glass substrate 1 when the glass substrate 1 is broken. On the upper surface of each of the fixed table 21 and the rotary table 22, a soft resin film 3 such as a thin and flexible soft urethane resin is disposed, and the glass substrate 1 to be broken is placed on the soft resin film 3 at the time of the break. Placed on. When the glass substrate 1 is placed on the soft resin film 3, the pressure acts evenly on the glass substrate 1, and the soft resin film 3 is higher than the fixed table 21 and the rotary table 22 just by placing the soft resin film 3 on the fixed table 21 and the rotary table 22. Since it has adhesiveness, there is no fear of shifting in the lateral direction with respect to the fixed table 21 and the rotary table 22. Therefore, it is not necessary to bond and fix with an adhesive or the like. In addition, a polytetrafluoroethylene layer having a thickness of about 0.1 mm known as Teflon (registered trademark) is provided on the contact surface of the soft resin film 3 with the glass substrate 1 as necessary. The glass substrate 1 can be easily peeled off.

A fixed side presser base 4 and a rotary side presser base 6 are disposed above the fixed table 21 and the rotary table 22. A hard urethane resin having a certain degree of rigidity for holding the glass substrate 1 against the fixed table 21 and the rotating table 22 at the lower ends of the fixed side holding base 4 and the rotating side holding base 6 and also having a certain degree of flexibility. Hard resin films 5 and 7 are provided. When a resin having flexibility such as urethane rubber is used as the hard resin films 5 and 7, when the glass substrate 1 is pressed strongly, it may be difficult to separate from the glass substrate 1 after breaking due to its adhesiveness. Further, the hard urethane resin has a certain degree of rigidity. Further, by providing a Teflon (registered trademark) layer on the glass contact surface in the same manner as the soft resin film 3, peeling from the glass substrate 1 is easy.

When the glass substrate 1 is placed on the soft resin film 3 provided on the upper surface of each of the fixed table 21 and the rotary table 22 at the time of a break, the planned cutting line 11 of the glass substrate 1 is fixed to the fixed table 21 and the rotary table. It is mounted so that it may be located in the gap between 22. A pusher opening 31 is formed at one end of the soft resin film 3 so that a pusher 8 to be described later can be freely inserted and removed, and the glass substrate 1 is scheduled to be cleaved in the gap between the fixed table 21 and the rotary table 22. A pusher 8 for pushing up the initial crack 11 formed at one end of the wire 11 from the back surface side of the glass substrate 1 is inserted so as to be freely accessible. The position of the lower surface of the soft resin film 3 corresponding to the position immediately below the scribe line 11 direction of the glass substrate 1 corresponds to the rotary shaft 9 of the rotary table 22, and the rotary table 22 is around the rotary shaft 9 in the direction of the arrow Y, That is, when the glass substrate 1 is broken, the glass substrate 1 rotates downward with respect to the plane of the glass substrate 1.

Next, the operation will be described. First, as shown in FIG. 2, the glass substrate 1 is placed on the soft resin film 3 on the break table 2 with the scribe line 10 facing down. At this time, the scribe line 10 formed on the glass substrate 1 is located in the gap between the fixed table 21 and the rotary table 22, and the direction of the scribe line 10 is parallel to the length direction of the fixed table 21 and the rotary table 22. Arrange as follows. Since the soft resin film 3 is flexible, the glass substrate 1 and the soft resin film 3 have high adhesion as well as the soft resin film 3 and the fixed table 21 and the rotary table 22 have high adhesion. doing. Therefore, there is no possibility that the glass substrate 1 is displaced from the soft resin film 3 in the surface direction. Further, due to the high adhesion between the glass substrate 1 and the soft resin film 3, the pressure at which the soft resin film 3 acts on the glass substrate 1 becomes uniform in the plane.

When the fixed side presser base 4 and the rotary side presser base 6 are moved downward in this state, the hard resin film 5 provided on the lower end of the fixed side presser base 4 is formed on the glass substrate 1 as shown in FIG. The glass substrate 1 is pressed against the fixed table 21 in contact with the surface. Therefore, a predetermined pressure is applied to the glass substrate 1 on the fixed table 21 side by the pressing force of the hard resin film 5. Similarly, the hard resin film 7 provided at the lower end of the rotary side holding base 6 also abuts on the upper surface of the glass substrate 1 and presses the glass substrate 1 against the rotary table 22, so that the glass substrate 1 on the rotary table 22 side is pressed. Also, a predetermined pressure is applied by the pressing force of the hard resin film 7. At this time, equal pressure is applied to the fixed table 21 side and the rotary table 22 side of the glass substrate 1 by equalizing the pressing force by the fixed side pressing base 4 and the rotating side pressing base 6. As a result, a preliminary force is applied to the scribe line 10 of the glass substrate 1 in the direction in which the scribe line 10 opens around the scribe line 10.

In this state, as shown in FIG. 7, the pusher 8 is inserted into the gap between the fixed table 21 and the rotary table 22, and is further inserted into the pusher opening 31 formed in the soft resin film 3. The position corresponding to the initial crack 11 on the back surface of the glass substrate 1 is pressed by the tip of 8. At this time, the initial crack 11 of the glass substrate 1 is in the vicinity of the left end portion of FIG. 7, and the scribe line 10 of the glass substrate 1 extends from the initial crack 11 in the right direction of FIG. While pressing the position corresponding to the initial crack 11 on the back surface of the glass substrate 1 with the tip of the pusher 8, as shown in FIG. 8, when the rotary table 22 is rotated downward about the rotation shaft 9, the glass substrate 1 is The soft resin film 3 starts to rotate in the arrow Y direction around the rotation axis 9 of the turntable 22.

The soft resin film 3 on the lower surface of the glass substrate 1 is flexible, and when the rotary table 21 rotates in the direction of the arrow Y around the rotation axis 9, the rotational force acts in the direction of bending the glass substrate 1 to cause the scribe line 10 to move. Although it acts so as to spread, it does not act in the direction of tearing the glass substrate 1, that is, the surface direction of the glass substrate 1. On the other hand, since the pressing force is applied to the back surface of the initial crack 11 of the glass substrate 1 by the pusher 8, the crack along the scribe line 10 proceeds from the initial crack 11 of the glass substrate 1 to the glass substrate 1. Since this crack progresses along the scribe line 10, and the glass substrate 1 has a pressing force applied to the initial crack 11 by the pusher 8 and a preliminary force is applied in the direction in which the scribe line 10 is opened. Progress also in the thickness direction. Therefore, the cleaving of the glass substrate 1 proceeds by progressing in the direction along the scribe line 10 of the crack and in the direction along the thickness of the glass substrate 1, and finally the cleaving reaches the end opposite to the initial crack 11. Break.

There is almost no chipping or shark teeth on the break surface of the glass substrate 1 thus broken. In addition, no residue such as cullet is generated. This is because the glass substrate 1 is not placed directly on the fixed table 21 and the turntable 22 but is placed via the soft resin film 3, so that the rotation force of the turntable 21 acting on the glass substrate 1. This is to buffer the breaking force that tears the glass.

In general, when the glass substrate 1 on which the scribe line 10 is formed is broken as in the present invention, the break table 2 and the fixed presser base 4 for uniformly applying a preliminary stress to the scribe line 10 are rotated. The presser base 5 requires high part machining accuracy, and is often difficult to adjust such as when installing parts or adjusting part positions during break machining. In the present invention, the soft resin film 3 is installed on the break table 2, and the hard resin layer 5.7 is provided on the contact surfaces of the fixed presser base 4 and the rotary presser base 5 with the glass substrate 1, and these soft resins are provided. Since the film 3 and the hard resin layer 5.7 are more flexible than metal materials, etc., it is possible to increase the tolerance of adjustment at the time of component processing accuracy, component installation, and break processing. The break device can be manufactured at a low cost.

In addition, it is preferable to control the pressing force of the pusher 8 from the back surface with respect to the initial crack 11 of the glass substrate 1 by a push-up distance of the pusher 8 so that the glass substrate 1 is not broken.

The thickness of the soft resin film 3 corresponds to the rotation axis offset between the center of the rotation shaft 9 of the turntable 21 and the glass substrate 1. Since the rotation axis offset affects the breaking action of the glass substrate 1 to be cleaved, it is preferable that the rotation axis offset varies depending on the thickness of the glass substrate 1 to be cleaved. Therefore, it is preferable to prepare several kinds of soft resin films 3 having different thicknesses so that they can be exchanged according to the thickness of the glass substrate 1 to be cleaved.

Further, the gap between the fixed table 21 and the rotary table 22 corresponds to the supporting distance of the glass substrate 1, and the gap between the hard resin film 5 of the fixed table 21 and the hard resin film 7 of the rotary table 22 is that of the glass substrate 1. Corresponds to the holding distance. Since these supporting distances and pressing distances also affect the breaking action of the glass substrate 1 to be cleaved, it is preferable that the distance can be adjusted according to the thickness of the glass substrate 1 to be cleaved.

When the break surface of the glass substrate 1 that was broken according to the present invention was observed in detail, the perpendicularity of the break surface was within 50 μm of deviation from the scribe line 10, chipping was 10 μm or less, and no shark teeth were observed. It was. Further, the strength of the glass substrate 1 after the break was 500 MPa or more according to the 4-point bending strength test, and there was little variation.

As described above, according to the present invention, in break processing of a glass substrate, particularly a high-strength glass substrate, the break line does not deviate from the scribe line, and the chip surface and the shark teeth are not generated on the break surface. A break method for a high-strength glass substrate that can be processed can be provided. Further, the break device can be easily processed and can be manufactured at low cost.

The glass substrate break method according to the present invention is suitable for application to mirror cleaving of high-strength glass, in particular, high-strength glass having a large area, where the break line is easily displaced from the scribe line and it is difficult to mirror-process the break surface. . "

DESCRIPTION OF SYMBOLS 1 Glass substrate 2 Break table 3 Soft resin film 4 Fixed side pressing base 6 Rotating side pressing base 5, 7 Hard resin film 8 Pusher 9 Rotating shaft 10 Scribe wire 11 Initial crack 21 Fixed table 22 Rotating table 31 Pusher opening

Claims (5)

  The break table for holding the glass substrate is composed of a fixed table and a rotary table that is adjacent to the fixed table with a predetermined gap and is rotatable around a predetermined rotation axis, and spans the fixed table and the rotary table. A flexible soft resin film is arranged on a glass substrate having an initial crack and a scribe line formed along a planned cutting line on one main surface so that the scribe line becomes the upper surface, and the fixed table and the rotary table. The glass substrate is scribed on the soft resin film so that one side is located on the fixed table and the other side is located on the rotary table with the scribe line as a boundary. Press the both sides of the scribe line with a hard resin layer having a predetermined rigidity and flexibility on the wire side surface, Glass substrate Break method, characterized in that rotation about the rotational axis of the glass substrate of the rotary table side together with the rotary table while applying.   The glass breaking method according to claim 1, wherein the glass breaking method is a high-strength glass substrate in which a reinforcing layer is formed on the surface of the glass substrate. The glass break method according to claim 1, wherein the soft resin film is a soft urethane resin. 2. The glass breaking method according to claim 1, wherein a polytetrafluoroethylene layer is provided on a contact surface of the soft resin film with the glass substrate. 2. The glass breaking method according to claim 1, wherein the thickness of the soft resin film is varied according to the thickness of the glass substrate to be cleaved.

Images