WO2011103798A1

WO2011103798A1 - Chemically strengthened glass capable of subsequently cutting

Info

Publication number: WO2011103798A1
Application number: PCT/CN2011/071155
Authority: WO
Inventors: 王冲; 乔斯·西默; 巴塞尔·马蒂亚斯
Original assignee: 肖特玻璃科技(苏州)有限公司; 尚光强
Priority date: 2010-02-26
Filing date: 2011-02-22
Publication date: 2011-09-01
Also published as: CN102167509A

Abstract

A chemically strengthened glass capable of subsequently cutting is provided. The glass has a Young's modulus of 70-100GPa, a Knoop hardness of 500-800kg/mm² (0.1/20, 100gf, 20s) and a CTE of 5.0-11.0×10^-6/°C.

Description

Chemical tempered glass capable of subsequent cutting

The present invention relates to a thin glass that can be cut after chemical tempering. Specifically, the present invention relates to a silicate glass having high strength, high fracture toughness, and high wear resistance, which has chemical tempering properties and can be laser cut after tempering. More specifically, the present invention relates to glass which can be used in electronic product screens and other fields involving high-strength thin glass, and which can perform subsequent laser cutting after chemical tempering. At the same time, the invention also relates to a chemical tempering process for the silicate glass. Background technique

Many fields of technology require high strength glass. The most typical way to increase the strength of the glass is to surface the glass, such as acid etching. Another method is to introduce permanent stresses into the glass, known as physical tempering (or hot tempering) and chemical tempering. Physical tempering introduces permanent stress by rapidly cooling the glass surface. Chemical tempering produces surface compressive stress by ion exchange. Both methods are well known and widely used in the industry. Substrate glass for electronic applications such as safety glass, automotive glass, white goods, hard drives, displays, etc. For touch screens, thin and reinforced cover glass is usually required to ensure both thinness and scratch resistance. Due to the thickness limitation, thin glass cannot produce a sufficiently high temperature gradient and cooling rate in the thickness direction, so it is difficult to be physically tempered. Thin glass, typically less than 2 mm thick, cannot be physically tempered. Therefore, thin glass having a thickness of less than 2 mm is usually selected from chemical tempering. Chemically tempered glass is known in the art and is described, for example, in the patents US 4,156,755 and DE 4,206,268 A1. The chemically tempered glass is machined such as edging, cutting, etc., which has a high defect rate or cannot be processed at all. This is because the higher internal stresses in the glass product during processing can lead to unpredictable cracking. However, in special processing processes, cutting tempered glass can bring significant economic benefits. In special cases, it is advantageous to cut the tempered thin glass because it can temper large pieces of flat glass and then cut it to increase the yield. The most common methods of glass cutting are, for example, mechanical cutter cutting, water jet or laser cutting. Laser cutting has the advantages of no chipping, difficulty in peeling and high boundary quality. The high quality of the boundary after laser cutting can eliminate the subsequent processing of the boundary, and the good surface quality can improve the scratch resistance of the glass, thereby eliminating the need for subsequent surface treatment. It is therefore necessary to obtain such high-strength glass that can be subjected to subsequent mechanical or laser cutting. The conventional glass cutting method uses mechanical force to cut the glass surface, and introduces an external force to separate the glass and complete the cutting. Using this method, microcracks remain on the edges of the glass, peeling, the glass surface is destroyed, and glass debris remains. Compared to traditional mechanical cutting, such as metal and diamond cutter wheel cutting, laser cutting is widely used in the field of glass cutting with its excellent cutting quality. For laser cutting, the glass is separated by the tension introduced by the laser. Taking CO ₂ laser cutting as an example, the CO ₂ laser can theoretically be completely absorbed by various glasses. There are three principles for CO ₂ laser cutting. In the first method, the glass is directly melted by a laser to separate the glass. At this time, the temperature of the glass is much greater than the transition point T _{g of the} glass. The second method, pulsed laser heating of the glass a slight dot-like areas to a portion slightly larger than the _temperature, T _g, the glass removed in these regions of the glass breaking. The third method, the glass is heated to a temperature slightly below the T _g, and then rapidly cooled. A crack caused by tension will separate the glass. Compared to traditional cutter wheel cutting, the third laser cutting method can reduce edge defects. It is enough to increase the mechanical strength of the glass. In addition, laser cutting is not limited by the shape of the cut, there is no mechanical wear, and it does not come into contact with the processed object, so that the laser cutting hardly produces glass debris, which is suitable for use in a clean room. Summary of the invention

The present invention relates to a chemically toughened glass that can be cut. Further, the glass is a silicate glass comprising aluminosilicate glass, borosilicate glass or the like. Further, the cutting method is performed by mechanical force or laser cutting. The present invention provides a glass article which is capable of laser cutting after chemical tempering. Further, the glass article may be a flat glass. Further, the glass product may be a glass tube. The thickness of the glass sheet is between 0.3 and 2.0 mm. The invention also provides a method of tempering in which the tempered glass is cleavable. Further, the glass is a silicate glass. The surface stress of the tempered glass is less than 1200 MPa. Further, the surface stress of the tempered glass is less than 900 MPa. Further, the surface stress of the tempered glass is less than 800 MPa. Further, the center stress of the tempered glass is less than 600 MPa. After tempering, the center stress of the glass is less than 60 MPao. Further, the center stress of the tempered glass is less than 40 MPa. Further, the center stress of the tempered glass is less than 20 MPao. Further, the center stress of the tempered glass is less than 15 MPa. The depth of the ion exchange layer of the tempered glass is less than 50 μm. Further, the depth of the ion exchange layer of the tempered glass is less than 30 μm. Further, the ion exchange of the tempered glass The layer depth is less than 20 μm. Further, the depth of the ion exchange layer of the tempered glass is less than 15 μm. The ratio of the ion exchange layer depth to the glass thickness of the tempered glass is less than 0.08. Further, the ratio of the depth of the ion exchange layer to the thickness of the glass after the tempered glass is less than 0.05. Further, the ratio of the depth of the ion exchange layer to the thickness of the glass of the tempered glass is less than 0.03. Further, the ratio of the ion exchange layer depth to the glass thickness of the tempered glass is less than 0.02. The value of the tempered glass (ion exchange layer depth X surface compressive stress ÷ glass thickness) should be less than 30. Further, the value of the tempered glass (ion exchange layer depth X surface compressive stress ÷ glass thickness) should be less than 20. Further, the value of the tempered glass (ion exchange layer depth X surface compressive stress + glass thickness) should be less than 10. Further, the value of the tempered glass (ion exchange layer depth X surface compressive stress ÷ glass thickness) should be less than 5. The invention also provides a method of cutting chemically tempered glass. Further, this method uses (0 ₂ laser for cutting. Further, the power of the CO ₂ laser beam is 50-1000 watts. Further, the power of the CO ₂ laser beam is in the range of 60-800 watts. the power of the laser beam _02. further, the power CO ₂ laser beam. further, the moving speed of the laser beam is 20-1500 mm / sec in the range of 80-300 watts in the range 80-500 watts. Further, the moving speed of the laser beam is between 40 and 1200 mm/sec. Further, the moving speed of the laser beam is between 60 and 800 mm/sec. Further, the moving speed of the laser beam is 80-500 mm/ Other laser cutting methods such as YAG: Nd laser, green laser, etc. can be used for the cutting of the chemically strengthened glass of the present invention.

Figure 1. Relationship between surface compressive stress, tensile stress, stress layer depth, and glass thickness (surface compressive stress is fixed at 800 MPa).

Figure 2. The photo shows the edge of a laser-cut chemically tempered glass. Figure 3. The photo shows the edge of a chemically tempered glass cut by a common cutter wheel. DETAILED DESCRIPTION OF THE INVENTION

During the chemical tempering process, the alkali metal ions with a large radius in the salt bath penetrate into the network structure of the glass by ion exchange, and exchange the alkali metal ions with a small radius in the glass to form a layer of tens of microns deep on the surface of the glass. Compressive stress layer. Glass strength is enhanced during this process. Protective cover glass for use in touch screen products such as smart phones, tablets, etc., typically requires chemical tempering to increase its strength and scratch resistance. Chemical tempered glass has different compressive stress range of 200-1500 MPa and ion exchange layer depth range of 10-150 micrometers due to different types of glass, chemical tempering salt bath composition, exchange time and temperature. In order to balance the compressive stress of the surface, the tensile stress accumulates in the middle of the glass. The magnitude of the tensile stress is related to the thickness of the glass, the surface compressive stress, and the depth of the ion exchange layer. The tensile stress of chemically tempered glass ranges from a few MPa to 100 MPa. Conventional glass cutting methods have difficulty scratching the surface of the tempered glass, or the depth of the scratch is not sufficient to cut the glass. As long as the depth of the ion exchange layer is greater than a certain limit, even if scratches are formed on the surface, since the ion exchange layer is not scratched, the externally applied tensile stress cannot be concentrated on the edge of the scratch, so that the entire glass cannot be broken along the scratch. And a random rupture occurs. Laser cutting can easily penetrate the compressive stress layer by heating the glass surface. During the first cooling and then cooling, the surface compressive stress of the glass is relaxed, and the resulting tensile stress creates cracks and extends downward to the central stress layer. This crack continues to expand and penetrates the entire glass center tensile stress layer. If the compressive stress of the underlying compressive stress layer is not particularly large, the energy released by the laser cutting may be sufficient to separate the compressive stress layer on the other side. The glass article described above may be a flat glass. Flat glass thickness in the range 0.1-10 mm, preferably in the range of 0.1-5 mm, more preferably in the range of 0.3-3 mm, the optimum range of 0.3-2 mm ₀ The tempered glass may have a size greater than 50 cm ² , may be greater than 100 cm ² , may be greater than 1000 cm ² , or may be greater than 2000 cm ² . The tempered glass may also have a size of less than 50 cm ² . Surprisingly, by adjusting the surface stress, exchange layer depth and central tensile stress of the tempered glass cut to a certain thickness, a high glass cutting yield can be obtained while maintaining a high breaking strength of the glass. The ion exchange process must be strictly controlled to achieve the corresponding cutting performance. Temperature, time and salt bath composition are the most important parameters. Surface treatment such as acid etching before chemical tempering can further increase the strength. Important parameters affecting glass cutting performance include Young's modulus and hardness. In addition, it is also important for laser cutting thermal expansion coefficient CTE. Young's modulus reflects the stiffness of the glass, preferably in the range of 70-100 MPa, more preferably in the range of 70-90 MPa, and the optimum range is 70-85 MPa = Knoop hardness of the glass (0.1/20, 100 gram force, The preferred range of 20 seconds) is

500-800 Kg/mm ² , more preferably 550-750 Kg/mm ² , and the optimum range is 550-700 Kg/mm ² .

CTE is the most important parameter for the tensile stress generated during the cooling of glass after heating. Large CTE glass will produce large tensile stress during the cutting process, making the glass easier to cut. However, if the CTE is too large, the glass will be susceptible to uncontrollable cracking due to thermal shock during cutting and chemical tempering. To meet these requirements, a preferred CTE range for glass 5.0-11.0xlO- ⁶ / ° C, more preferably in the range of 5.0-10.0xlO ^'6 / ° C, the optimal range of 5.0-9.0xlO- ⁶ / ° C. The mechanical properties of glass products after chemical tempering are defined by the surface compressive stress (CS), central tensile stress (CT) and ion exchange layer depth (DoL) of the glass. Higher surface stresses can produce higher fracture strength, higher center gravity increases the risk of glass breakage, and ion exchange layer depth reflects the glass's scratch resistance. Chemical tempering can increase the breaking strength of the glass and also increase the surface hardness and scratch resistance of the glass, so it is difficult to cut the tempered glass by conventional glass processing methods and equipment. By obtaining a chemically tempered glass with a specific ion exchange layer depth, surface stress and central tensile stress, the glass can be cut. The lower the central tensile stress, the better the cutting of tempered glass. The central tensile stress should be less than 60 MPa, more preferably less than 40 MPa, more preferably less than 20 MPa, and most preferably less than 15 MPa. The surface compressive stress of the chemically tempered glass should be less than 1200 MPa, more preferably less than 900 MPa, preferably less than 800 MPa, preferably less than 600 MPao. The depth of the ion exchange layer is in the range of 0-50 microns, preferably in the range of 0- 30 microns, more preferably 0-20 microns, with an optimum range of 0-15 microns. Because the central tension is determined by the ion exchange layer depth, the surface compressive stress and the glass thickness; in addition, the chemically tempered glass must also satisfy the ion exchange layer depth and the glass thickness ratio of less than 0.08, more preferably less than 0.05, and preferably less than 0.03. , preferably less than 0.02. In addition, laser-cut chemically tempered glass must meet a range of conditions such as thickness, surface compressive stress, and ion exchange layer depth:

The value of (ion exchange layer depth X surface compressive stress ÷ glass thickness) should be less than 30, more preferably less than 20, preferably less than 10, and most preferably less than 5. For example, as shown in Figure 1, when the surface compressive stress is fixed at 800 MPa, the central tensile stress of different thicknesses of glass varies with the depth of the ion exchange layer as shown. If the central tensile stress layer is required to be equal to 40 MPa, the depth of the ion exchange layer should be: 0.3 mm of glass of about 15 μm, 0.5 mm of glass of about 25 μm, 0.7 mm of glass of about 35 μm, and 1.0 mm of glass of about 50 μm. The chemically tempered glass was subjected to CO ₂ laser cutting. CO ₂ laser beam power Within the range of 50-1000 watts, the power of the optimized CO ₂ laser beam is in the range of 60-800 watts, and the power of the better CO ₂ laser beam is in the range of 80-500 watts, the optimal CO ₂ laser The power of the beam is in the range of 80-300 watts. Moreover, the moving speed of the laser beam is between 20 and 1500 mm/sec, the moving speed of the optimized laser beam is between 40 and 1200 mm/sec, and the moving speed of the better laser beam is 60-800 mm/sec. The optimal movement speed of the laser beam is

Between 80-500 mm / sec. Sodium aluminosilicate glass contains Na+ ions and is a typical glass that can be chemically tempered. This glass has a coefficient of thermal expansion between 4 and 15 ppm. The ion exchange between Na ⁺ o K+ was carried out in a KNO ₃ salt bath. The glass is usually treated in a salt bath furnace at a temperature of 390-460 ° C for 1-8 hours. The ion exchange layer of the glass thus treated has a depth of between 10 and 120 microns. Shorter processing times and lower processing temperatures are advantageous for laser cutting. In a specific embodiment, the temperature of the salt bath ranges from 380 to 440 ° C, more preferably from 380 to 420 ° C, and most preferably from 380 to 400 ° C. The treatment time is 1 to 4 hours, more preferably 1 to 3 hours, and preferably 1 to 2 hours. Lithium aluminosilicate glass is an aluminosilicate glass containing Li ₂ 0. Since the inclusion of Li ₂ O means that such a glass can be treated with a NaNO ₃ salt bath, and because Li ⁺ →Na+ diffuses rapidly in the salt bath, it has a fast ion exchange rate. The surface compressive stress of NaN0 ₃ treated glass is usually lower than that of KNO ₃ treated glass, but the depth of ion exchange layer can be easily reached.

100 microns. Such a deep ion exchange layer depth makes such tempered glass impossible to cut. However, the cutting of the glass can be achieved by controlling the chemical tempering conditions. The time and temperature for tempering with NaNO ₃ are: 1-60 minutes, preferably 1-30 minutes, preferably 1-15 minutes, temperature 360-390 ° C, better at 360-380 ° C, most Good for 360-370 ° C. In addition, if the glass is treated with KNO ₃ , since the diffusion speed of Li + ^ K ⁺ is low, the depth of the ion exchange layer is small, that is,

5-20 microns, the glass thus treated can be laser cut. Borosilicate glass is a silicate glass containing a certain amount of B ₂ O ₃ as a network structure. This glass tends to have a lower coefficient of thermal expansion. Because of the presence of B ₂ O ₃ , the network structure of the glass is denser than ordinary silicate glass. Dense structure leads to the exchange of alkali metal ions The velocity into the glass structure is relatively slow and the depth of the ion exchange layer is not deep. Therefore, after chemical tempering, the glass can be laser cut. The optimized temperature range for chemical tempering is

390-500 ° C, more preferably in the range of 400-490 ° C, the optimum range is 420-480 ° C, and the tempering time is optimized in the range of 1-30 hours, more preferably in the range of 1-20 hours, the most preferred range is 1-15 hours. Furthermore, the depth of the ion exchange layer should be less than 15, 20, 30, 50 microns, and the fracture strength should be at least 100% higher than that of the untempered glass. Furthermore, other elements may be added to the composition of the glass to increase the absorption of the laser. The above laser wavelengths may be in the ultraviolet UV, visible VIS and infrared IR bands. Usually, but not necessarily, rare earth elements such as barium are added. The composition of the relevant glass ranges as follows:

The sodium aluminosilicate glass comprises the following components, and the percentage of each component is (wt%) based on the total weight of the glass composition:

Na ₂ O 2-17%,

K ₂ O 2-10%;

Na ₂ O+K ₂ O 5-25%;

Α1 ₂ Ο ₃ 2-20%;

B ₂ O ₃ 0-15%;

MgO 0-10%;

ZnO 0-5%;

ZrO ₂ 0-5%;

CaO 0-5%; the preferred ingredient content is (wt%):

SiO ₂ 58-65%;

Na ₂ O 10-15%, K ₂ O 2-6%;

Na ₂ O+K ₂ O 13-20%;

Al ₂ O ₃ 12-18%;

B ₂ O ₃ 0-5%;

MgO 0-6%;

ZnO 0-2%;

ZrO ₂ 0-4%;

CaO 0-5%; The following amounts of the following refining agents can be added, but are not limited. For example: arsenic oxide, antimony oxide, tin oxide, chloride, sulfide, and the like. Lithium aluminosilicate glass, comprising the following components, based on the total weight of the glass composition, the percentage of each component is (wt%):

SiO ₂ 55-70%;

Na ₂ O 0-10%;

Ll ₂ W l - L "/o ;

K ₂ O 0-10%;

Li ₂ O+Na ₂ O 2-20%;

AI2O3 2-25%;

B ₂ O ₃ 0-15%;

P ₂ O ₅ 0-5%;

ZnO 0-5%;

ZrO ₂ 0-5%;

The preferred range of ingredients is:

SiO ₂ 60-70%;

Na ₂ O 0-10%;

Li ₂ O 3-10% _;

K ₂ O 0-2%;

Li ₂ O+Na ₂ O 4-16%; Al ₂ O ₃ 10-20%;

B ₂ O ₃ 0-6%;

P ₂ O ₅ 0-3%;

ZnO 0-2%;

ZrO ₂ 0-5%; The following amount of the following refining agent can be added, but there is no limitation. For example: arsenic oxide, antimony oxide, tin oxide, chloride, sulfide, etc. The borosilicate glass comprises the following components, and the percentage of each component is (wt%) based on the total weight of the glass composition:

SiO ₂ 55-85%;

Na ₂ O 0-20%;

K ₂ O 0-15%;

Β ₂ Ο ₃ 0.5-20%;

Α1 ₂ Ο ₃ 0-10%;

TiO ₂ 0~8%;

ZnO 0~10%.

The preferred range of ingredients is:

SiO ₂ 60-83%;

Na ₂ O 0-10%;

K ₂ 0 0-10%;

Β ₂ Ο ₃ 2-16%;

Α1 ₂ Ο ₃ 0-8%;

TiO ₂ 0~6%;

ZnO 0~8%. A general amount of the following refining agent can be added, but there is no limitation. For example, arsenic oxide, antimony oxide, tin oxide, chloride, sulfide. Soda lime glass, comprising the following components, the percentage of each component is (wt%) based on the total weight of the glass composition:

SiO ₂ 60-80%;

Na ₂ O 1-20%;

K ₂ O 0-5%;

CaO 0.5-20%;

MgO 0-15%;

Al ₂ O ₃ 0 to 10%.

The preferred range of ingredients is:

SiO ₂ 60-80%;

Na ₂ O 8-16%;

K ₂ O 0-4%;

CaO 4-15%;

MgO 2-6%;

AI2O3 0~5%. A general amount of the following refining agent can be added, but there is no limitation. For example, arsenic oxide, antimony oxide, tin oxide, chloride, sulfide. The above glass components may each include CeO ₂ 0-l%. In the following examples, all component amounts are calculated by weight percent unless otherwise stated. In order to achieve a good cutting effect, it is necessary to control the surface compressive stress, the central tensile stress, and the depth of the stress layer after the glass tempering. For glass tempered with KNO ₃ , the stress magnitude and depth can be measured with the FSM6000. For lithium aluminosilicate glass, especially in the case of NaN0 ₃ tempering, the FSM6000 cannot measure the surface compressive stress and the depth of the stress layer. It can be measured by the principle of stress birefringence using a polarizing microscope. Embodiment 1

The main components of the glass are SiO ₂ 63%, Α1 ₂ Ο ₃ 16%, Na ₂ O 13%, K ₂ O 3.55%, MgO 3.95%, and the balance is SnO ₂ . First, according to the ingredients given in the examples in Table 1, the corresponding raw materials are compounded, and the raw materials are melted through platinum crucible at 1600-1640 ° C for 5 to 15 hours, and then clarified at 1640-1660 ° C, followed by Cool down to around 1600 °C. The platinum crucible was taken out from the high temperature furnace, and the glass melt was poured into a cold stainless steel mold to obtain a bulk glass having a size of approximately 50 x 50 x 40 mm. The glass is then annealed in an annealing furnace at about 600 ° C for 2 to 8 hours. The annealed glass is polished, then cut, edging, and finely diced to the desired sample size, i.e., 40 x 40 x 0.7 mm. The surface roughness after polishing is below 1 nm. The coefficient of thermal expansion and the conversion point were determined by the following methods. That is, the measurement is performed by a dilatometer. The sample was processed into a cylinder having a diameter of 5 mm. The amount of change in length from 20 to 300 ° C was recorded to calculate the coefficient of linear expansion. Near the glass transition point, the linear expansion coefficient of the glass undergoes a significant abrupt change, and the transition point of the glass is obtained by extrapolation. The density of the glass was determined by the Archimedes principle. The volume of the sample is obtained by placing the glass sample in a container filled with water and accurately measuring the volume change of the water in the container. Density data is obtained by dividing the weight of the sample that can be accurately measured by the volume. The polished sample was chemically tempered. The tempering is carried out in a laboratory-scale small salt bath furnace (diameter 250x250mm, depth 400mm). The sample is placed on a special corrosion-resistant stainless steel sample holder. Pass 390 in a KNO ₃ salt bath. C, after 2 hours of ion exchange treatment, Measurement, surface stress 820 Mpa, center stress 20 Mpa, and stress layer depth 20 μηι. Cutting with a CO ₂ laser with a laser power of 150 W and a laser beam moving speed of 100 mm/sec, the glass can be cut smoothly. The edge quality is good. Embodiment 2

A glass sample was prepared in the same manner as in Example 1. The glass sample has a thickness of 0.7 mm. The chemical tempering was carried out in a pure KNO ₃ salt bath at 440 ° C for 6 hours. The surface stress is 700 MPa, the center stress is 45 MPa, and the stress layer depth is 40 μm. Cutting with a C0 ₂ laser, the laser beam power and moving speed are adjusted, and the glass cannot be cut smoothly. The reason is that the stress layer depth and the central tensile stress are too large. Embodiment 5

A glass sample was prepared in the same manner as in Example 1. The glass sample has a thickness of 1.0 mm. Chemical tempering was carried out in a pure KNO ₃ salt bath at 390 ° C for 8 hours. The surface stress is 1000 Mpa, the center stress is 10 Mpa, and the stress layer depth is 10 μm. Cutting with a CO ₂ laser with a laser power of 100 W and a laser beam moving speed of 180 mm/sec, the glass can be cut smoothly. The edge quality is good. The quality of the glass edge can be seen in Figure 2. At the same time, the glass can be cut by a conventional glass cutting table with a cutter wheel, as shown in Figure 3. However, a large number of small gaps are generated at the edge, and large-scale production cannot be performed. Example 7

A glass sample was prepared in the same manner as in Example 1. The glass sample has a thickness of 0.5 mm. The chemical tempering was carried out in a pure NaNO ₃ salt bath at 380 ° C for 10 minutes. The surface stress is 650 Mpa, the center stress is 10 Mpa, and the stress layer depth is 14 μm. Cutting with a C0 ₂ laser, the laser power is 100W, the laser beam moving speed is 200mm/sec, and the glass can be cut smoothly. The edge quality is good. Example ten

A glass sample was prepared in the same manner as in Example 1. The sample thickness is 0.3 mm. The chemical tempering was carried out in a pure KNO ₃ salt bath at 420 ° C for 3 hours. The surface stress is 500 Mpa, the center stress is 14 Mpa, and the stress layer depth is 8 μιη. Cutting with a CO ₂ laser with a laser power of 100 W and a laser beam moving speed of 200 mm/sec, the glass can be cut smoothly. The edge quality is good. Embodiment 11

A glass sample was prepared in the same manner as in Example 1. The sample thickness was 1.0 mm. Chemical tempering was carried out in a pure KNO ₃ salt bath at 460 ° C for 8 hours. The surface stress is 300 Mpa, the center stress is 5 Mpa, and the stress layer depth is 16 μm. Cutting with a CO ₂ laser with a laser power of 120 W and a laser beam moving speed of 150 mm/sec, the glass can be cut smoothly. The edge quality is good. Applications include display glass for consumer electronics and optics. The cutting method may be any cutting method, but it is preferably laser cutting such as CO ₂ , Nd-YAG laser or femtosecond laser. It can also be cut with a water knife and a mechanical cutter wheel. Example

Claims

Rights request

1. A chemically tempered glass capable of subsequent cutting, characterized in that the Young's modulus of the glass is 70-100 MPa, and the Knoop hardness of the glass (0.1/20, 100 gram force, 20 seconds) is

The CTE of 500-800 Kg/mm ² and glass is 5.0-11.0 xl (T ⁶ /.C.

2. The chemically toughened glass capable of subsequent cutting according to claim 1, characterized by a Young's modulus of 70 to 90 MPa.

3. The chemically toughened glass capable of subsequent cutting according to claim 1, characterized in that the Young's modulus is 70-85 MPao

4. The chemically toughened glass capable of subsequent cutting according to claim 1, characterized in that the glass has a Knoop hardness of 550-750 Kg/mm ²

5. The chemically toughened glass capable of subsequent cutting according to claim 1, characterized in that the glass has a Knoop hardness of 550 to 700 Kg/mm ² .

6. The chemically toughened glass capable of subsequent cutting according to claim 1, characterized in that the glass CTE is 5.0-10.0 x ^{10 - 6} / ° C o

7. The chemically toughened glass capable of subsequent cutting according to claim 1, characterized in that the glass CTE is 6.0-9.5 x lO- ⁶ / °Co

A chemically toughened glass capable of subsequent cutting according to any of the preceding claims, wherein said tempered glass is one of the following:

1) The glass is a sodium aluminosilicate glass comprising the following components, the percentage of each component being (wt%) based on the total weight of the glass composition:

SiO ₂ 55-70%; Na ₂ 0 2-17%; K ₂ O 2-10%; Na ₂ O+K ₂ O 5-25%; Α1 ₂ Ο ₃ 2-20%; B ₂ O ₃ 0-15%; MgO 0-10%; ZnO 0-5%; ZrO ₂ 0-5%; CaO 0-5%;

2) The glass is a lithium aluminosilicate glass comprising the following components, the percentage of each component being (wt%) based on the total weight of the glass composition:

SiO ₂ 55-70%; Na ₂ O 0-10%; Li ₂ O 1-15%; K ₂ O 0-10%; Li ₂ O+Na ₂ O 2-20%; Α1 ₂ Ο ₃ 2-25 %; Β ₂ Ο ₃ 0-15%; Ρ ₂ Ο ₅ 0-5%;; ΖηΟ 0-5%; ZrO ₂ 0-5%;

3) The glass is a borosilicate glass comprising the following components, the percentage of each component being (wt%) based on the total weight of the glass composition:

SiO ₂ 55-85%; Na ₂ O 0-20%; K ₂ O 0-15%; Β ₂ Ο ₃ 0.5-20%; Α1 ₂ Ο ₃ 0-10%; TiO ₂ 0~8%; ΖηΟ 0 ~10%; or

4) The glass is soda-lime glass, comprising the following components, the percentage of each component being (wt%) based on the total weight of the glass composition:

Si0 ₂ 60-80%; Na ₂ 0 1-20%; K ₂ O 0-5%; CaO 0.5-20%; MgO 0-15%; AI O3 0~10%.

9. A chemically tempered glass capable of subsequent cutting according to claim 8, said tempered glass having the following preferred components:

SiO ₂ 58-65%; Na ₂ O 10-15%; K ₂ O 2-6%; Na ₂ O+K ₂ O 13-20%; Α1 ₂ Ο ₃ 12-18%; B ₂ O ₃ 0- 5%; MgO 0-6%; ZnO 0-2%; ZrO ₂ 0-4%; CaO 0-5%;

SiO ₂ 60-70%; Na ₂ O 0-10%; Li ₂ O 3-10%; K ₂ O 0-2%; Li ₂ O+Na ₂ O 4-16%; Α1 ₂ Ο ₃ 10-20 %; Β ₂ Ο ₃ 0-6%; Ρ ₂ Ο ₅ 0-3%; ΖηΟ 0-2%; ZrO ₂ 0-5%; 3) the glass is borosilicate glass, including the following components, The total weight of the glass composition, the percentage of each component is (wt%):

SiO ₂ 60-83%; Na ₂ 0 0-10%; K ₂ O 0-10%; Β ₂ Ο ₃ 2-16%; Α1 ₂ Ο ₃ 0-8%; TiO ₂ 0~6%; ZnO 0 -8%; or

4) The glass is soda-lime glass, including the following components, the percentage of each component is (wt%) based on the total weight of the glass composition: SiO ₂ 60-80%; Na ₂ 0 8-16%; K ₂ O 0-4%; CaO 4-15%; MgO 2-6%; Al ₂ O ₃ 0-5%.

10. The chemically toughened glass capable of subsequent cutting according to claim 8 or 9, which may further comprise 0-1 wt% of CeO ₂ .

11. A chemically toughened glass capable of subsequent cutting according to any of the preceding claims, characterized in that the surface compressive stress is less than 1200 MPa.

12. The chemically toughened glass capable of subsequent cutting according to claim 11, characterized in that the surface compressive stress is less than 900 MPa.

A chemically toughened glass capable of subsequent cutting according to claim 12, characterized in that the surface compressive stress is less than 800 MPa.

14. A chemically toughened glass capable of subsequent cutting according to claim 13, characterized in that the surface compressive stress is less than 600 MPa.

15. A chemically toughened glass capable of subsequent cutting according to any of the preceding claims, characterized in that the central tensile stress is less than 60 MPa.

16. A chemically toughened glass capable of subsequent cutting as claimed in claim 15 wherein the central tensile stress is less than 40 MPa.

17. A chemically tempered glass capable of subsequent cutting according to claim 16, characterized in that the central tensile stress is less than 20 MPa.

18. A chemically toughened glass capable of subsequent cutting according to claim 17, characterized in that the central tensile stress is less than 15 MPa.

19. A chemically toughened glass capable of subsequent cutting according to any of the preceding claims, characterized in that the ion exchange layer has a depth of less than 50 [mu]m.

20. A chemically tempered glass capable of subsequent cutting according to claim 19, characterized in that the ion exchange layer has a depth of less than 30 μm.

A chemically tempered glass capable of subsequent cutting according to claim 20, wherein the ion exchange layer has a depth of less than 20 μm.

22. A chemically tempered glass capable of subsequent cutting according to claim 21, characterized in that the ion exchange layer has a depth of less than 15 μm.

23. A chemically toughened glass capable of subsequent cutting according to any of the preceding claims, characterized in that the ion exchange layer depth and the glass thickness ratio are below 0.08.

24. The chemically toughened glass capable of subsequent cutting according to claim 23, characterized in that the ratio of the depth of the ion exchange layer to the thickness of the glass is less than 0.05.

25. The chemically toughened glass capable of subsequent cutting according to claim 24, characterized in that the ion exchange layer depth and the glass thickness ratio are less than 0.03.

26. The chemically toughened glass capable of subsequent cutting according to claim 25, characterized in that the ratio of the depth of the ion exchange layer to the thickness of the glass is less than 0.02.

27. A chemically toughened glass capable of subsequent cutting according to any of the preceding claims, characterized in that the value of (ion exchange layer depth X surface compressive stress ÷ glass thickness) is less than 30.

28. The chemically toughened glass capable of subsequent cutting according to claim 27, characterized in that the value of (ion exchange layer depth X surface compressive stress ÷ glass thickness) is less than 20.

29. The chemically toughened glass capable of subsequent cutting according to claim 28, characterized in that (the ion exchange layer depth X surface compressive stress ÷ glass thickness) has a value of less than 10.

30. A chemically tempered glass capable of subsequent cutting according to claim 29, characterized in that (the ion exchange layer depth X surface compressive stress ÷ glass thickness) has a value of less than 5.

31. A chemically toughened glass capable of subsequent cutting according to any of the preceding claims, characterized in that it is capable of laser cutting after chemical tempering.

32. The chemically toughened glass capable of subsequent cutting according to claim 31, characterized in that the laser cutting is a < 0 ₂ laser, a YAG: Nd laser, a green laser cutting.

33. A chemically tempered glass capable of subsequent cutting according to claim 32, characterized in that the power of the CO ₂ laser beam is 50-1000 watts.

A chemically tempered glass capable of subsequent cutting according to claim 32, wherein the moving speed of the laser beam is 20 to 1500 mm / sec.

35. A chemically toughened glass capable of subsequent cutting according to any of the preceding claims, characterized in that the thickness of the glass sheet is from 0.3 to 2.0 mm.

36. A chemically tempered glass product capable of subsequent cutting, characterized in that the Young's modulus of the glass article is 70-100 MPa, and the Knoop hardness (0.1/20, 100 gram force, 20 seconds) of the glass article is 500- The CTE of 800 Kg/mm ² and glass articles is 5.0-11.0 xlO' ⁶ /°C.

37. A tempered glass article according to claim 36, characterized in that the glass article is a flat glass or a glass tube.