TWI471279B - Processing method and processing apparatus for a chemically strengthened glass substrate - Google Patents

Description

Processing method and processing equipment for a chemically strengthened glass substrate

The invention relates to a processing method and a processing device for a glass substrate, in particular to a processing method and a processing device for a chemically strengthened glass substrate.

At present, glass substrates are widely used in various parts of electronic products, such as screens and casings. In order to prevent the glass substrate from being easily scratched or broken, the glass substrate generally used for electronic products is reinforced. In the manufacturing process, the glass substrate needs to be cut into a smaller size glass substrate to match the application of various electronic parts. However, the tempered glass substrate is difficult to be cut or scratched so that it is difficult to process and is incompletely processed, or the tempered glass substrate is easily broken or defective due to the need for a large cutting force.

Referring to FIG. 1 , the chemically strengthened glass substrate 1 includes a tensile layer 11 and at least one compression layer 12 formed on the tensile layer 11 . Here, the compression layer 12 is formed by replacing a part of sodium ions (Na+) in the chemically strengthened glass substrate 1 with potassium ions (K+). Since the volume of potassium ions is larger than the sodium ions, the compression layer 12 having a larger unstressed volume is subjected to the tensile layer 11 having a smaller unstressed volume, so that the tensile layer 11 has tensile internal stress. And the compression layer 12 has a compressive internal stress.

In a conventional technique, in order to make the chemically strengthened glass substrate 1 easier to cut, the glass substrate 1 is strengthened by chemically strengthening the glass substrate 1 to cause a stress relaxation effect (Stress Relaxation Effect). Among them, the causes of stress relaxation include: 1. Viscoelasticity Effect (Viscoelastic Effect), and 2. Mutual Diffusion of ions. The interdiffusion of ions causes the potassium ions in the compression layer 12 to gradually diffuse into the tensile layer 11, thereby reducing the compressive internal stress of the compression layer 12 of the chemically strengthened glass substrate 1, so that the chemically strengthened glass substrate 1 is easier to cut. However, if the chemically strengthened glass substrate 1 is subjected to ion diffusion, even if the chemically strengthened glass substrate 1 is cooled afterwards, the compressive internal stress of the compressive layer 12 is permanently lowered, and the chemically strengthened glass substrate 1 is easily broken or scratched.

In view of this, how to reduce the compressive internal stress of the compressive layer 12 of the chemically strengthened glass substrate 1 during the cutting stage, so that the chemically strengthened glass substrate 1 is easier to cut, and the finished product maintains the resistance to breakage and scratching of the chemically strengthened glass substrate 1. For this reason, an industry has to solve the problem.

An object of the present invention is to provide a processing method and processing apparatus for a chemically strengthened glass substrate, which makes the chemically strengthened glass substrate easier to cut.

The chemically strengthened glass substrate comprises a stretched layer and at least one compressed layer formed on the stretched layer, the stretched layer has tensile internal stress and the compressed layer has a compressive internal stress.

To achieve the above object, the processing method of the present invention comprises the steps of: (a) heating at least one predetermined heating portion of the chemically strengthened glass substrate to a cutting temperature during a heating, wherein the cutting temperature is substantially between 200 and 300 degrees Celsius , to reduce the compressive internal stress of the compression layer of the predetermined heating portion, and the heating period is less than 10 minutes to avoid ion diffusion phenomenon of the chemically strengthened glass substrate; and (b) cutting the chemically strengthened glass substrate at the predetermined heating portion.

To achieve the above object, the processing apparatus of the present invention comprises a heating head and a cutting head. The heating head is configured to heat at least one predetermined heating portion of the chemically strengthened glass substrate to a cutting temperature during a heating, wherein the cutting temperature is substantially between 200 and 300 degrees Celsius to reduce compression of the compression layer of the predetermined heating portion Internal stress, and the heating period is less than 10 minutes Clock to avoid ion diffusion in the chemically strengthened glass substrate. The cutting head is used to cut the chemically strengthened glass substrate at a predetermined heating portion.

1‧‧‧Chemically tempered glass substrate

11‧‧‧ Stretch layer

12‧‧‧Compression layer

3‧‧‧Processing equipment

30‧‧‧Predetermined heating section

301‧‧‧Predetermined cutting line

303‧‧‧ scribing openings

31‧‧‧Heating head

31a‧‧‧Laser source

31b‧‧‧burner

31c‧‧‧hot air generator

33‧‧‧ cutting head

35‧‧‧heating platform

1 is a schematic cross-sectional view of a chemically strengthened glass substrate; FIGS. 2A to 2C are schematic views showing an embodiment of the processing apparatus of the present invention; and FIG. 2D is a schematic view showing one embodiment of a heating platform using the processing apparatus of the present invention; And Fig. 3 is a schematic view showing one embodiment of the chemically strengthened glass substrate processed from the opposite sides of the chemically strengthened glass substrate while the processing apparatus of the present invention is being used.

Referring to FIG. 1, the processing method of the present invention is applied to a chemically strengthened glass substrate 1. The chemically strengthened glass substrate 1 includes a stretched layer 11 and at least one compressive layer 12 formed on the stretched layer 11. Among them, the compression layer 12 is formed by replacing ions having a small volume in the chemically strengthened glass substrate 1 but having a large thermal expansion coefficient with ions having a large volume but a small thermal expansion coefficient, and such replacement can strengthen the glass. For example, the compression layer 12 is formed by replacing a part of the chemically strengthened glass substrate 1 having a small volume but a large coefficient of thermal expansion (Na+) with a potassium ion (K+) having a large volume but a small thermal expansion coefficient. Not limited to this embodiment).

Since the volume of potassium ions is larger than the sodium ions, the compression layer 12 having a larger unstressed volume is subjected to the tensile layer 11 having a smaller unstressed volume, so that the tensile layer 11 has tensile internal stress. And the compression layer 12 has a compressive internal stress. The steps involved in the processing method of the present invention are detailed below.

The chemically strengthened glass substrate 1 can be maintained at a loss-proof temperature between 25 degrees Celsius and -55 degrees Celsius before the chemically strengthened glass substrate 1 is subjected to processing such as cutting to maintain the compressive internal stress of the compression layer 12 to prevent chemistry. The tempered glass substrate 1 is susceptible to damage such as scratches.

Please refer to FIGS. 2A to 2C, when the chemically strengthened glass substrate 1 is to be processed by cutting or the like. At least one predetermined heating portion 30 of the chemically strengthened glass substrate 1 is heated to a cutting temperature during a heating period so that the coefficient of thermal expansion of the sodium ions in the tensile layer 11 is greater than the coefficient of thermal expansion of the potassium ions in the compression layer 12. The thermal expansion of the tensile layer 11 is greater than the thermal expansion of the compression layer 12, and is reduced by the compressive internal stress of the compression layer 12 of the predetermined heating portion 30. Among them, the cutting temperature is substantially between 200 and 300 degrees Celsius. Preferably, the cutting temperature is substantially between 250 ± 25 degrees Celsius.

It should be noted here that the heating period is less than 10 minutes to avoid the stress relaxation effect of the chemically strengthened glass substrate 1. Among them, the causes of stress relaxation include: 1. Viscoelastic effect, and 2. Mutual Diffusion. The interdiffusion of ions causes the potassium ions in the compression layer 12 to gradually diffuse into the tensile layer 11. When the ion-diffusion phenomenon occurs in the chemically strengthened glass substrate 1, the compressive internal stress of the compressive layer 12 is permanently lowered, and the chemically strengthened glass substrate 1 is more likely to be damaged or scratched.

As shown in FIGS. 2A to 2C, if the chemically strengthened glass substrate 1 is to be cut along the predetermined cutting line 301 by the processing apparatus 3, the chemically strengthened glass substrate 1 is heated at least along the predetermined cutting line 301 to the cutting temperature in this heating step.

In the above-described step of heating to make the chemically strengthened glass substrate 1 easier to be machined, the predetermined heating portion 30 may be heated by various heating methods such as laser, burner, or hot air. As shown in FIG. 2A, the above heating step can generate a carbon dioxide laser having a wavelength of 10.6 μm, a carbon dioxide laser having a wavelength of 9.4 μm, or a Yttrium Aluminum Garnet (YAG laser) heating by the laser source 31a. The heating portion 30 is predetermined. As shown in Fig. 2B, the above heating step can heat the predetermined heating portion 30 by burning the combustible material of butane, propane or petroleum products by the burner 31b. As shown in Fig. 2C, the above heating step may be performed by hot air generator 31c using nickel chrome wire or induction heating to heat the gas or generate water vapor to generate hot air to heat the predetermined heating portion. As shown in FIG. 2D, the above heating step can be electrical resistance, induction heating (induction) A heating platform 35 is heated by a burner, or a steam, and the chemically strengthened glass substrate 1 is placed on the heating stage 35 to at least partially heat the chemically strengthened glass substrate 1.

After the above heating step, the compressive internal stress of the chemically strengthened glass substrate 1 on the compression layer 12 of the predetermined heating portion 30 is lowered, making the chemically strengthened glass substrate 1 easier to cut at the predetermined heating portion 30. After that, the heated chemically strengthened glass substrate 1 is cut by the cutting head 33 at the predetermined heating portion 30, thereby preventing the chemically strengthened glass substrate 1 from being incompletely cut due to excessive compressive internal stress of the compression layer 12 or requiring large cutting. The chemically strengthened glass substrate 1 is broken or causes defects.

As shown in FIGS. 2A through 2C, in the cutting step, the chemically strengthened glass substrate 1 can be scored along the predetermined cutting line 301 by the cutting head 33 on the compression layer 11 to form a scored opening 303. The method of forming the scribe opening 303 may be to scribe the chemically strengthened glass substrate 1 along a predetermined cutting line 301 by a cutting wheel, a diamond knife or a laser-based cutting head 33.

In the above-described cutting step, the so-called cutting is performed by cutting the chemically strengthened glass substrate 1 along the predetermined cutting line 301 to form the scribed glass 303, and cutting the chemically strengthened glass substrate 1 in addition to the above-described cutting. The tempered glass substrate 1 is drilled or the surface is removed.

In one embodiment, as shown in FIG. 3, the heating step and the cutting step can simultaneously heat and cut the chemically strengthened glass substrate 1 from opposite sides of the chemically strengthened glass substrate 1, respectively. The chemically strengthened glass substrate 1 shown in FIG. 3 may be a single glass substrate or two glass substrates bonded to each other. When the chemically strengthened glass substrate 1 shown in FIG. 3 is a single glass substrate, the heating step and the cutting step are simultaneously performed on the front and back surfaces of the chemically strengthened glass substrate 1 including only a single glass substrate. When the chemically strengthened glass substrate 1 shown in FIG. 3 includes two glass substrates bonded to each other, the glass substrate to which the chemically strengthened glass substrates 1 are bonded to each other is subjected to the heating step and the cutting step simultaneously from the front and back surfaces.

After the cutting step, the chemically strengthened glass substrate 1 can be cooled to help or accelerate the chemistry The tempered glass substrate 1 is split into a plurality of portions along the scribe opening 303. Wherein, in this step, the chemically strengthened glass substrate 1 is cooled to a splitting temperature between 2 and -55 degrees Celsius.

The above cooling step may cool the chemically strengthened glass substrate 1 by various conventional methods, for example, by chemically strengthening the glass substrate 1 by natural cooling, or by forcibly cooling the chemically strengthened glass substrate 1 with water, cold air, a cryogenic liquid or a low temperature gas.

The processing apparatus 3 used in the above-described processing method of the present invention will be described in detail below. As shown in FIGS. 2A to 2C, the processing apparatus 3 of the present invention is used for the chemically strengthened glass substrate 1 as described above, which comprises a heating head 31 and a cutting head 33.

The heating head 31 is for heating at least a predetermined heating portion 30 of the chemically strengthened glass substrate 1 to a cutting temperature during a heating. Wherein, the cutting temperature is substantially between 200 and 300 degrees Celsius, so that the thermal expansion coefficient of the sodium ion in the tensile layer 11 is greater than the thermal expansion coefficient of the potassium ion in the compression layer 12, so that the thermal expansion of the tensile layer 11 is greater than that of the compression layer. The thermal expansion of 12 is lowered by the compressive internal stress of the compression layer 12 of the predetermined heating portion 30, so that the chemically strengthened glass substrate 1 is more easily machined at the predetermined heating portion 30. Preferably, the cutting temperature at which the heating head 31 heats the chemically strengthened glass substrate 1 is substantially between 250 ± 25 degrees Celsius.

It should be noted here that the heating period is less than 10 minutes to avoid the ion diffusion phenomenon of the chemically strengthened glass substrate 1, and the potassium ions in the compression layer 12 are gradually diffused into the tensile layer 11. When the ion-diffusion phenomenon occurs in the chemically strengthened glass substrate 1, the compressive internal stress of the compressive layer 12 is permanently lowered, and the chemically strengthened glass substrate 1 is more likely to be damaged or scratched.

The heating head 31 can use various heating methods. For example, the predetermined heating portion 30 is heated by a laser, a burner, or a hot air.

As shown in FIG. 2A, the heating head 31 can be a laser source 31a and emits a carbon dioxide laser having a wavelength of 10.6 μm, a carbon dioxide laser having a wavelength of 9.4 μm or a Yttrium Aluminum Garnet (YAG laser). The predetermined heating portion 30 is heated.

As shown in FIG. 2B, the heating head 31 can be a burner 31b and burns butane. (Butane), propane or petroleum product, heating the predetermined heating portion 30.

As shown in Fig. 2C, the heating head 31 may be a hot air generator 31c, and uses a nickel-chromium wire or induction heating to heat the gas or generate water vapor to generate hot air to heat the predetermined heating portion 30.

As shown in FIG. 2D, the heating head 31 can include a heating platform 35 and heat the platform 35 with electrical resistance, induction heating, burners, or steam. As shown in FIG. 2D, the chemically strengthened glass substrate 1 is provided on the heating stage 35 to at least partially heat the chemically strengthened glass substrate 1.

As shown in FIGS. 2A to 2C, if the chemically strengthened glass substrate 1 is to be cut along a predetermined cutting line 301, the heating head 31 heats the chemically strengthened glass substrate 1 at least along the predetermined cutting line 301 to the cutting temperature.

As shown in Figs. 2A to 2C, after the heating head 31 heats the predetermined heating portion 30, the cutting head 33 is used to cut the chemically strengthened glass substrate 1 at the predetermined heating portion 30.

As shown in FIGS. 2A through 2C, in one embodiment, the cutting head 33 is scribed on the compression layer 12 along the predetermined cutting line 301 to scribe the chemically strengthened glass substrate 1 to form a scribe opening 303. Wherein, the cutting head 33 can score the chemically strengthened glass substrate 1 along a predetermined cutting line by a cutting wheel, a diamond knife or a laser to form the scribe opening 303.

In addition to the above-described cutting of the chemically strengthened glass substrate 1 along the predetermined cutting line 301 to form the scribe opening 303 to cut the chemically strengthened glass substrate 1, the cutting head 33 may also perform drilling or removal of the surface of the chemically strengthened glass substrate 1.

In one embodiment, as shown in FIG. 3, the heating head 31 and the cutting head 33 can simultaneously heat and cut the chemically strengthened glass substrate 1 from opposite sides of the chemically strengthened glass substrate 1, respectively. The chemically strengthened glass substrate 1 shown in FIG. 3 may be a single glass substrate or two glass substrates bonded to each other. When the chemically strengthened glass substrate 1 shown in FIG. 3 is a single glass substrate, the heating step and the cutting step are simultaneously performed on the front and back surfaces of the chemically strengthened glass substrate 1 including only a single glass substrate. When the chemically strengthened glass shown in Figure 3 When the glass substrate 1 includes two glass substrates bonded to each other, the glass substrate to which the chemically strengthened glass substrate 1 is bonded to each other is subjected to the heating step and the cutting step simultaneously from the front and back surfaces.

The processing apparatus 3 of the present invention is preferably exemplified by maintaining the chemically strengthened glass substrate 1 at an anti-loss temperature between 25 and -55 degrees Celsius before the heating head 31 heats the predetermined heating portion 30 of the chemically strengthened glass substrate 1. The chemically strengthened glass substrate 1 is prevented from being damaged by, for example, scratching or the like in order to maintain the compressive internal stress of the compression layer 12.

The processing apparatus 3 of the present invention preferably further includes a cooling device (not shown). The cooling device is used to cool the chemically strengthened glass substrate 1 after the cutting head 33 cuts the chemically strengthened glass substrate 1 to help or accelerate the chemically strengthened glass substrate 1 to be split into a plurality of portions along the scribing opening 303. Among them, the cooling device can cool the chemically strengthened glass substrate 1 to a splitting temperature between 25 and -55 degrees Celsius.

The cooling device can cool the chemically strengthened glass substrate 1 by various conventional methods, for example, by chemically strengthening the glass substrate 1 by natural cooling, or forcibly cooling the chemically strengthened glass substrate 1 with water, cold air, a cryogenic liquid or a low temperature gas.

1‧‧‧Chemically tempered glass substrate

3‧‧‧Processing equipment

30‧‧‧Predetermined heating section

301‧‧‧Predetermined cutting line

303‧‧‧ scribing openings

31‧‧‧Heating head

31a‧‧‧Laser source

33‧‧‧ cutting head

Claims (30)

A processing method for a chemically strengthened glass substrate, wherein the chemically strengthened glass substrate comprises a tensile layer and at least one compression layer formed on the tensile layer, the tensile layer has tensile internal stress and the compression layer Having a compressive internal stress, and the processing method comprises the steps of: (a) heating at least one predetermined heating portion of the chemically strengthened glass substrate to a cutting temperature during a heating, wherein the cutting temperature is substantially between 200 and 300 Celsius Degree to reduce the compressive internal stress of the compression layer of the predetermined heating portion, and the heating period is less than 10 minutes to avoid stress relaxation effect (Stress Relaxation Effect) of the chemically strengthened glass substrate; and (b) The chemically strengthened glass substrate is cut at the predetermined heating portion. The processing method according to claim 1, wherein the processing method further comprises the following steps before the step (a): (a-0) maintaining the chemically strengthened glass substrate at a loss between 25 and -55 degrees Celsius The temperature is maintained to maintain the compressive internal stress of the compression layer to prevent damage to the chemically strengthened glass substrate. The processing method of claim 2, wherein the cutting temperature is substantially between 250 ± 25 degrees Celsius. The processing method of claim 3, wherein in step (a), the chemically strengthened glass substrate is heated to at least the predetermined cutting line to the cutting temperature, and the step (b) is attached to the compressive layer. A predetermined cutting line scribes the chemically strengthened glass substrate to form a scored opening. The processing method of claim 4, wherein after the step (b), the processing method further comprises the steps of: (c) cooling the chemically strengthened glass substrate such that the chemically strengthened glass substrate is along the moment The opening is split into a plurality of parts. The method of claim 5, wherein in step (c), the chemically strengthened glass substrate is cooled to a splitting temperature between 25 degrees Celsius and -55 degrees Celsius. The processing method according to claim 5, wherein the chemically strengthened glass substrate is naturally cooled in the step (c), or the chemically strengthened glass substrate is forcibly cooled by water, cold air, a cryogenic liquid or a low temperature gas. The processing method of claim 4, wherein in step (b) the chemically strengthened glass substrate is scored along the predetermined cutting line by a cutting wheel, a diamond knife or a laser to form the scored opening. The processing method of claim 3, wherein the step (a) heats the predetermined heating portion with a laser, a burner, or hot air. The processing method of claim 9, wherein the step (a) heats the predetermined one with a carbon dioxide laser having a wavelength of 10.6 μm, a carbon dioxide laser having a wavelength of 9.4 μm, or a Yttrium Aluminum Garnet (YAG laser). Heat the part. The processing method of claim 9, wherein the step (a) heats the predetermined heating portion with a burner for burning a combustible substance of butane, propane or petroleum products. The processing method of claim 9, wherein the step (a) utilizes nickel chrome wire or induction heating to heat the gas or generate water vapor to generate hot air to heat the predetermined heating portion. The processing method according to claim 9, wherein the step (a) and the step (b) respectively heat and cut the chemically strengthened glass substrate from opposite sides of the chemically strengthened glass substrate. The processing method of claim 2, wherein the step (a) heats a heating platform by electric resistance, induction heating, a burner, or steam, and places the chemically strengthened glass substrate on the heating platform to The chemically strengthened glass substrate is heated. The processing method of claim 2, wherein in step (b), the chemically strengthened glass substrate is cut, drilled or removed. A processing apparatus for a chemically strengthened glass substrate, wherein the chemically strengthened glass substrate comprises a tensile layer and at least one compression layer formed on the tensile layer, the tensile layer has tensile internal stress and the compression layer Having a compressive internal stress, and the processing apparatus includes: a heating head for heating at least one predetermined heating portion of the chemically strengthened glass substrate to a cutting temperature during a heating, wherein the cutting temperature is substantially between 200 ° C 300 degrees to reduce the compressive internal stress of the compression layer of the predetermined heating portion, and the heating period is less than 10 minutes to avoid stress relaxation effect (Stress Relaxation Effect) of the chemically strengthened glass substrate; And a head for cutting the chemically strengthened glass substrate in the predetermined heating portion. The processing apparatus of claim 16, wherein the processing apparatus maintains the chemically strengthened glass substrate at a temperature between 25 and -55 degrees Celsius before the heating head heats the predetermined heating portion of the chemically strengthened glass substrate The damage prevention temperature prevents the compressive internal stress of the compression layer from being damaged by the chemically strengthened glass substrate. The processing apparatus of claim 17, wherein the cutting temperature is substantially between 250 ± 25 degrees Celsius. The processing apparatus of claim 18, wherein the heating head heats the chemically strengthened glass substrate at least along a predetermined cutting line to the cutting temperature, and the cutting head is scribed on the compression layer along the predetermined cutting line The glass substrate is chemically strengthened to form a scored opening. The processing apparatus of claim 19, wherein the processing apparatus further comprises a cooling device, and the cooling device is configured to cool the chemically strengthened glass substrate after the cutting head cuts the chemically strengthened glass substrate to make the chemically strengthened glass The substrate along the moment The opening is split into a plurality of parts. The processing apparatus of claim 20, wherein the cooling device cools the chemically strengthened glass substrate to a splitting temperature between 25 degrees Celsius and -55 degrees Celsius. The processing apparatus of claim 20, wherein the cooling device cools the chemically strengthened glass substrate naturally, or forcibly cools the chemically strengthened glass substrate with water, cold air, a cryogenic liquid, or a low temperature gas. The processing apparatus of claim 19, wherein the cutting head scores the chemically strengthened glass substrate along the predetermined cutting line with a cutting wheel, a diamond knife or a laser to form the scored opening. The processing apparatus of claim 18, wherein the heating head heats the predetermined heating portion with a laser, a burner, or hot air. The processing apparatus of claim 24, wherein the heating head heats the predetermined heating with a carbon dioxide laser having a wavelength of 10.6 μm, a carbon dioxide laser having a wavelength of 9.4 μm, or a Yttrium Aluminum Garnet (YAG laser). Part. The processing apparatus of claim 24, wherein the heating head heats the predetermined heating portion with a burner that burns butane, propane, or petroleum products. A processing apparatus according to claim 24, wherein the heating head heats the gas or generates water vapor using nickel chrome wire or induction heating to generate hot air to heat the predetermined heating portion. The processing apparatus according to claim 24, wherein the heating head and the cutting head respectively heat and cut the chemically strengthened glass substrate from opposite sides of the chemically strengthened glass substrate. The processing apparatus of claim 17, wherein the heating head is heated by a resistor, an induction heating, a burner, or a steam, and the chemically strengthened glass substrate is disposed on the heating platform. Heating the chemical strengthening glass substrate. The processing apparatus of claim 17, wherein the chemically strengthened glass substrate is cut, drilled or removed from the surface.