Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides the matte toughened protective glass and the preparation method thereof, so as to solve the problems that the strength of the existing toughened glass is not ideal or the intensity of the existing matte toughened protective glass is not ideal.
In order to achieve the object, in one aspect of the present invention, there is provided a matte tempered cover glass. The matte toughened protective glass comprises a toughened glass substrate, wherein the toughened glass substrate is provided with two opposite surfaces, at least one surface of the toughened glass substrate is a matte surface, and the matte toughened protective glassThe strength of (A) satisfies: the center falling strength of 500g steel ball satisfies that y is (0.25+ akx-bx)2) +/-F, the values of a and b are related to haze, and the value of a is 0.07-0.085, and the value of b is 0.0005-0.0007; when the matte toughened protective glass is soda-lime glass, k is 1; when the matte toughened protective glass is aluminum-silicon glass, k is 1.25; when the matte toughened protective glass is lithium aluminum silicate glass, k is 1.27; f is 0-0.1.5, and x is the thickness of the matte toughened protective glass; and the impact energy density of the matte toughened protective glass is 2.8 multiplied by 105J/m2-2.5×106J/m2。
In another aspect of the invention, two preparation methods of the matte toughened protective glass are provided. The preparation method of the matte toughened protective glass comprises the following steps:
providing a glass substrate to be tempered, wherein the glass substrate is provided with two planes which are oppositely arranged;
carrying out matte processing treatment on at least one plane of the glass substrate;
heating the glass substrate after the matte surface machining treatment to a temperature lower than the TG point of the glass substrate for heat treatment;
and placing the glass substrate subjected to the heat treatment in a toughening environment without thermal shock for toughening treatment.
The other preparation method of the matte toughened protective glass comprises the following steps:
providing a glass substrate to be tempered, wherein the glass substrate is provided with two planes which are oppositely arranged;
carrying out matte processing treatment on at least one plane of the glass substrate;
carrying out primary toughening treatment on the glass substrate after the matte processing treatment;
placing the glass substrate subjected to the first tempering treatment in air at the temperature of 300-600 ℃ for ion heat transfer treatment;
and carrying out secondary toughening treatment on the glass substrate subjected to the ion thermal migration treatment.
In another aspect, the invention provides application of the fog-surface toughened protective glass in preparation of a two-dimensional code protection device, an instrument display protection device, a display advertisement screen and an exhibition reading protection screen.
Compared with the prior art, the matte toughened protective glass has high mechanical strength on the basis of containing a matte, and the impact energy density of the matte toughened protective glass can reach 2.8 multiplied by 10 after being measured5J/m2-2.5×106J/m2And the haze transmittance and haze of the matte surface are high.
According to the preparation method of the matte toughened protective glass, the matte processing treatment is firstly carried out on one surface of the glass substrate, and then the glass substrate with the matte is toughened for multiple times, so that the prepared matte toughened protective glass has high mechanical strength on the basis of having the matte; on the other hand, the preparation method has easily controlled process conditions, can effectively ensure the stability of high mechanical properties of the prepared matte toughened protective glass, and has high haze transmittance and high haze.
Because the fog tempered protective glass has high mechanical strength and high fog transmittance and haze, the fog tempered protective glass can endow the protective screen or the advertising screen with high mechanical strength when being applied to the protective screen or the advertising screen, so that the fog tempered protective glass has the characteristics of high strength, impact resistance and damage resistance, and simultaneously has high transmittance and efficient anti-glare property.
Detailed Description
In order to make the technical problems, technical solutions and advantageous effects to be solved by the present invention more clearly apparent, the present invention is further described in detail below with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
In one aspect, the embodiment of the invention provides a fog-surface toughened protective glass. The structure of the matte toughened protective glass is shown in fig. 1, and comprises a toughened glass substrate 1, wherein the toughened glass substrate 1 has two opposite surfaces, one surface is a surface 11, the other surface is a surface 12, the surface 11 is a matte surface, the surface 12 can be a matte surface, or both the surface 11 and the surface 12 can be a matte surface.
The toughened glass substrate 1 of the matte toughened protective glass has high mechanical properties, the matte toughened protective glass is endowed with high impact strength, and the strength of the matte toughened protective glass is measured to meet the following requirements: y ═ 0.25k + akx-bx2) F, the values of a and b are related to haze, and a is between 0.07 and 0.085 and b is between 0.0005 and 0.0007; f is between 0 and 0.1.5, and x is the thickness of the matte toughened protective glass, wherein the test of the central falling ball strength of the steel ball can be carried out according to the following method:
as shown in figure 4, 500g steel ball and glass center point top are free falling impact, from 0.3m to test, each height is measured to 5, each glass is impacted once, if not broken, the glass is taken down, the same batch of glass is changed to test, if the number of intact glass is more than 2, the height is increased by 0.05m, then 5 pieces are taken to test, if the glass is broken, the second highest point is taken as the center falling ball strength.
Wherein y is (0.25k + akx-bx)2) K in the formula +/-F is related to the type of the material of the toughened glass substrate 1, for example, the toughened glass substrate 1 can be, but not limited to, the following toughened glass:
in one embodiment, the tempered glass substrate 1 is tempered soda-lime glass, in which caseAnd y is (0.25k + akx-bx)2) K in the +/-F formula is 1, and the toughened soda-lime glass can bear 1m of central falling ball of 500g of steel ball without being broken when the thickness of the toughened soda-lime glass is 7mm or more. Specifically, when the toughened soda-lime glass only contains one fog face, the non-fog face of the toughened soda-lime glass can bear 1m of the falling ball of the steel ball of 500g without being broken. Further measuring the compressive stress of the toughened soda-lime glass is 400-700Mpa, and the depth of the compressive stress is 6-20 mu m.
In another embodiment, the tempered glass matrix is tempered aluminosilicate glass, and in this case, y ═ 0.25k + akx-bx2) K in the +/-F formula is 1.25, and the toughened aluminum silicon glass bears 1m central falling ball of 500g steel ball without being broken when the thickness of the toughened aluminum silicon glass is measured to be 6mm or more. Specifically, when the toughened aluminum-silicon glass only contains one fog face, the non-fog face of the toughened aluminum-silicon glass can bear 1m of central falling balls of 500g of steel balls without being broken. Further measuring that the compressive stress of the toughened aluminum-silicon glass is 600-950MPa, and the depth of the compressive stress is 30-100 mu m.
In another embodiment, the toughened glass substrate is toughened lithium aluminosilicate glass, and in this case, y ═ 0.25k + akx-bx2) K in the formula +/-F is 1.27, and the toughened lithium aluminum silicon glass can bear 1m of central falling balls of 500g of steel balls without being broken when the thickness of the toughened lithium aluminum silicon glass is measured to be 5mm or more. Specifically, when the toughened lithium aluminum silicon glass only contains one fog face, the non-fog face of the toughened lithium aluminum silicon glass can bear 1m of central falling balls of 500g of steel balls without being broken. Further measuring the compressive stress of the toughened lithium aluminum silicon glass at 700-1200MPa and the compressive stress depth at 200-1000 μm.
Therefore, the toughened glass substrate made of the material is selected to endow the matte toughened protective glass with high mechanical strength, so that the matte toughened protective glass has the advantages of high strength, impact resistance and breakage resistance.
In one embodiment, the haze 11 included in the tempered glass substrate 1 of the matte tempered cover glass has an arithmetic average roughness Ra of 0.009-1.3 μm, a maximum peak-to-valley depth Ry of 0.075-9.2 μm, and a profile average width Rsm of 38.0-300 μm.
In another embodiment, the haze of the matte is 55% to 85%, preferably 70% to 80%; the myopia transmittance of the matte is 70% -90%, preferably 80% -88%. In addition, the thickness of the fog layer of the fog surface can be controlled to be 10-50 μm, and the preferable thickness of the fog layer is 10-20 μm. The characteristics of the matte 11, such as roughness, peak-valley depth, fog layer thickness, haze and myopia transmittance, can effectively ensure that the matte toughened protective glass has high myopia transmittance, effectively avoid light reflection, increase diffuse reflection, prevent glare effect caused by mirror reflection of light under the action of strong light, so as to achieve the effect of preventing glare and avoid halation caused by a flash lamp, and when the matte toughened protective glass is used for a two-dimensional code protective screen, the characteristics of the matte 11 can ensure the speed and success rate of code scanning; on the other hand, the high mechanical strength of the toughened glass substrate 1 is not influenced.
Wherein the Ra, Ry, and Rsm methods are evaluated as shown in FIG. 3.
The arithmetic average roughness Ra calculation method comprises the following steps: the arithmetic mean of the profile offset values over length L is calculated as formula I below, and the parameters for Ra are evaluated as shown in FIG. 3-A:
the maximum valley-peak depth Ry calculation method comprises the following steps: taking 10 sections of areas for testing to obtain the vertical height Ry of the maximum peak and the trough of each sectionmaxThe technical formula is shown as the following formula II, and the parameters for evaluating Ry are shown as the graph 3-B:
Ry=(Ry1+Ry2+……+Ryi)/i Ⅱ
the method for calculating the mean width of the contour Rsm comprises the following steps: an average of the contour element widths Xs over a sample length; the technical formula is shown as the following formula III, and the parameters for evaluating the Rsm are shown as a graph 3-C:
Rsm=(Xs1+Xs2+……+Xsi)/i Ⅲ。
in a further embodiment, the matte toughened protective glass further comprises an anti-fouling layer 2, and the anti-fouling layer 2 is laminated and bonded on the other surface 12 of the toughened glass substrate 1 opposite to the matte 11, that is, the toughened glass substrate 1 has two opposite surfaces, one of which is the matte 11, and the anti-fouling layer 2 is laminated and bonded on the other surface 12, as shown in fig. 2. The anti-fouling layer 2 endows the surface of the fog-surface toughened protective glass with anti-fouling performance, and effectively prevents the fog-surface toughened protective glass from being polluted by water stains, oil stains and the like. Therefore, when the fog-surface toughened protective glass is used for a protective screen such as a two-dimensional code protective screen, the surface laminated with the antifouling layer 2 is used as the outer surface, so that the observation surface of the protective screen can be effectively kept clean, and the observation effect or the code scanning effect is improved. In a specific embodiment, the thickness of the antifouling layer 2 can be controlled to be 3 to 50 nm. In addition, the anti-fouling layer 2 may be a coating layer formed of an anti-fouling material, and in a specific embodiment, may be a fluorosilicone compound coating layer or a composite anti-fouling coating layer formed of a silica coating layer and a fluorosilicone compound coating layer. The thickness of the fluorine-silicon hydrolysis compound coating can be controlled to be 4-30nm, and the thickness of the silicon dioxide coating can be controlled to be 3-20 nm. Wherein, the fluorine group in the fluorine-silicon hydrolytic compound can be composed of at least one of a perfluoropolyether group, a perfluoroalkylene group and a perfluoroalkyl group. The fluorine-containing group is bonded to a silicon atom of a hydrolyzable silyl group to form a fluorine-containing hydrolyzable silicon compound, wherein the silyl group is hydrolyzed to become silanol groups, and then the silanol groups are dehydrated to form siloxane bonds composed of-Si-O-Si-, thereby forming a fluorine-containing organosilicon compound coating layer having water repellency and oil repellency, effectively preventing the antifouling layer 2 of the matte tempered protective glass from being polluted by, for example, water stains and the like, and maintaining the cleanliness of the antifouling layer 2.
In addition, the overall thickness of the matte toughened protective glass can be adjusted according to the requirements of practical application, and in one embodiment, the total thickness of the matte toughened protective glass can be 2-20 mm. In addition, the examination shows that the pressure stress (surface pressure stress) of the matte toughened protective glass is 400-1200MPa, and the depth of the pressure stress is 6-1000 μm. The measured impact energy density of the matte toughened protective glass can reach 2.8 multiplied by 105J/m2-2.5×106J/m2. Therefore, the matte toughened protective glass still has high mechanical strength on the basis of containing a matte surface, and the haze transmittance and the haze of the matte surface are high.
The pressure stress (surface pressure stress) of the matte toughened protective glass is measured by adopting an FSM-6000 stress meter, and the actual pressure stress depth is jointly measured by adopting the pressure stress depth and an SLP-1000 stress meter. The determination of the impact resistance energy density is based on the method for testing the central falling ball strength of the steel ball, and the ratio of the energy of the impact surface of the falling ball to the impact area when the falling ball at the center of the glass is at the highest non-breaking point is obtained, wherein the energy of the impact surface is the kinetic energy E of the falling ball impacting the surface of the glass, and the impact area is the area S of the falling ball impacting the surface of the glass. Energy density is E/S.
On the other hand, on the basis of the matte toughened protective glass, the embodiment of the invention also provides a preparation method of the matte toughened protective glass.
In an embodiment, a process flow of the method for preparing the matte tempered protective glass is shown in fig. 5, and the method for preparing the matte tempered protective glass comprises the following steps:
s01, providing a glass substrate to be tempered, wherein the glass substrate is provided with two planes which are oppositely arranged;
s02, performing matte processing on at least one plane of the glass substrate;
s03, heating the glass substrate after the matte processing treatment to a temperature lower than the TG point of the glass substrate for heat treatment;
and S04, placing the glass substrate after the heat treatment in a toughening environment without thermal shock for toughening treatment.
In step S01, the glass substrate to be tempered is the tempered glass substrate 1 of the above-mentioned matte tempered protective glass. Therefore, the glass matrix to be tempered is preferably soda lime glass, aluminosilicate glass, lithium aluminosilicate glass and the like, and is preferably soda lime glass.
The step S02 is executed to form a matte on a surface of the glass substrate to be tempered, such as the matte 11 of the above-mentioned matte tempered protective glass. Therefore, the haze formed by the haze processing in the step S02 has an average roughness Ra of 0.009-1.3 μm, an average peak-to-valley depth Rz of 0.075-9.2 μm, and an average width of profile Rsm of 38.0-300 μm; the thickness of the fog layer is 10-50 μm, preferably 10-20 μm; the haze of the matte surface is 55-85%, and preferably 70-80%; the myopia transmittance of the matte is 70% -90%, preferably 80% -88%.
The method for processing the matte surface can be a conventional matte surface processing method in the glass field, for example, the method can but not only comprise a conventional AG processing method, and specifically comprises a sand blasting method, an etching method, a spraying method, a sol-gel method and the like. Wherein, the AG processing treatment also comprises an HF acid cleaning treatment process to improve the near-sightedness transmittance of the matte surface and improve the speed and success rate of code scanning.
In the step S03, the glass substrate processed in the step S02 is heat-treated to close microcracks caused during the matte finishing process of the glass substrate in the step S02, so as to ensure and improve the mechanical strength of the glass substrate. Wherein the temperature of the heat treatment depends on the type of the glass substrate, and may be, for example, a sufficient high temperature blocking treatment performed at about 100 ℃ lower than the TG point temperature of the glass substrate. In one embodiment, the glass substrate is soda-lime glass, and the heat treatment temperature is 500-600 ℃ for 10-60 min. By controlling the heat treatment temperature and time, microcracks generated in the matte processing treatment process of the glass matrix are fully closed. Wherein, the glass microcracks are generated in the processes of processing and transporting glass, and the microcracks are easily generated in the glass and on the surface of the glass; the glass heat treatment means that the glass containing the microcracks is subjected to high-temperature treatment before strengthening, so that the microcracks of the glass are eliminated in a bridging manner, the purpose of increasing the intrinsic strength is achieved, the high-temperature microcracks are bridged, namely, after the heat treatment, the high-temperature glass enters a salt bath to be strengthened, does not stay in the air at room temperature, and the phenomenon that the microcracks are generated again on the glass due to thermal shock caused by rapid temperature change is avoided.
In step S04, the method of tempering includes the steps of: and (3) placing the glass substrate in a pure potassium nitrate salt bath at 400-460 ℃ without thermal shock for toughening treatment for 4-24h, such as 6-24 h. And (4) toughening the glass substrate treated in the step (S03) to form a pressure stress layer on the surface layer of the prepared matte toughened protective glass, so that the prepared matte toughened protective glass has high mechanical strength, high haze transmittance and high haze. The thermal shock refers to a phenomenon of thermal expansion and cold contraction caused by sudden temperature change, so that the thermal shock-free condition refers to the condition that the temperature of tempering treatment is stable, and the phenomenon of sudden temperature change and the like does not exist in the embodiment of the invention.
In another embodiment, another process flow of the above method for preparing the matte toughened protective glass is shown in fig. 6, and the method for preparing the matte toughened protective glass comprises the following steps:
s01', providing a glass substrate to be tempered, wherein the glass substrate is provided with two planes which are oppositely arranged;
s02', performing matte processing treatment on at least one plane of the glass substrate;
s03', performing primary toughening treatment on the glass substrate after the matte processing treatment;
s04', placing the glass substrate after the first tempering treatment in the air at the temperature of 300-600 ℃ for ion heat transfer treatment;
and S05', performing secondary toughening treatment on the glass substrate subjected to the ion thermal migration treatment.
Wherein the glass substrate to be tempered in the step S01' is the tempered glass substrate 1 of the matte tempered protective glass. Therefore, the glass matrix to be tempered is preferably soda lime glass, aluminosilicate glass, lithium aluminosilicate glass and the like, and is preferably aluminosilicate glass and lithium aluminosilicate glass.
The matte finishing process in step S02' is the same as the matte finishing process in step S02. Therefore, the matte processing treatment in step S02' is also to form a matte on a surface of the glass substrate to be tempered, such as forming the matte 11 of the above-mentioned matte tempered protective glass. The average roughness Ra of the fog face formed by the fog face processing treatment in the step S02' is within a range of 0.009-1.3 mu m, the average peak-valley depth Rz is within a range of 0.075-9.2 mu m, and the average width Rsm of the contour is within a range of 38.0-300 mu m; the thickness of the fog layer is 10-50 μm, preferably 10-20 μm; the haze of the matte surface is 55-85%, and preferably 70-80%; the myopia transmittance of the matte is 70% -90%, preferably 80% -88%.
In step S03 ', the glass substrate processed in step S02 ' is subjected to a first tempering treatment to form a compressive stress layer on the surface layer of the glass substrate, and in an embodiment, when the glass substrate is the aluminosilicate glass in step S01 ', the first tempering treatment method includes the following steps: the glass matrix is placed in a pure potassium nitrate salt bath at 400-460 ℃ for toughening treatment for 4-24h, such as 6-24 h; in another embodiment, when the glass is lithium aluminosilicate glass, the method for the first tempering treatment comprises the following steps: and (3) placing the glass substrate in a pure sodium nitrate salt bath at 370-450 ℃ for toughening treatment for 2-48h, such as 12-48 h. And forming a compressive stress layer on the surface layer of the glass substrate processed in the step S02' through the first tempering treatment.
In the step S04 ', the glass substrate after the first tempering treatment in the step S03 ' is subjected to ion thermal migration treatment, so that ions in the surface layer of the glass substrate after the first tempering treatment in the step S03 ' migrate toward the deep layer of the glass substrate, thereby increasing the depth of the compressive stress layer. In one embodiment, when the glass matrix aluminosilicate glass in the step S01' is used, the temperature of the ion thermal migration treatment is 300-; in another embodiment, when the glass is lithium aluminum silicate glass, the temperature of the ion thermal migration treatment is 300-450 ℃ and the time is 30-60 min.
In step S05 ', the glass substrate after the ion thermal migration treatment in step S04' is subjected to a second tempering treatment to enhance the compressive stress on the surface layer of the glass substrate, in an embodiment, the glass is an aluminosilicate glass, and the method of the second tempering treatment includes the following steps: the glass matrix is placed in a pure potassium nitrate salt bath at 400-460 ℃ for toughening treatment for 4-24h, such as 6-24 h; in another embodiment, when the glass is lithium aluminosilicate glass, the method for the second tempering treatment comprises the following steps: and (3) placing the glass in a pure potassium nitrate salt bath at 380-460 ℃ for toughening treatment for 0.5-8h, such as 1-8 h. And further improving the depth and the magnitude of the compressive stress layer formed on the surface layer of the glass substrate through the secondary toughening treatment. Therefore, the preparation method of the matte toughened protective glass has the advantage that the depth of the compressive stress layer formed on the surface layer of the glass substrate is large, and the compressive stress is large by carrying out two times of toughening treatment and combining ion thermal migration treatment.
According to the two preparation methods of the matte toughened protective glass, the matte toughened protective glass prepared by the preparation method of the matte toughened protective glass has high mechanical strength and high haze transmittance and haze. As proved by inspection, the prepared matte toughened protective glass has the advantages of 2.8 multiplied by 105J/m2-2.5×106J/m2The impact energy density of (a); specifically, in an embodiment, when the glass substrate to be tempered in step S01 or step S01' is soda lime glass, the compressive stress of the prepared matte tempered protective glass is measured to be 400-700Mpa, and the depth of the compressive stress is measured to be 6-20 μm; in another embodiment, when the glass substrate to be tempered in step S01 or step S01' is aluminosilicate glass, the compressive stress of the prepared matte tempered protective glass is 600-950Mpa, and the depth of the compressive stress is 30-100 μm; in another embodiment, when the glass substrate to be tempered in step S01 or step S01' is lithium aluminosilicate glass, the compressive stress of the prepared matte tempered protective glass is 700-.
Further, after the step S04 and/or the step S05', the method further includes a step of forming an anti-fouling layer on the prepared matte tempered protective glass, that is, on the other plane of the glass substrate opposite to the matte 11, so as to form an anti-fouling layer 2 on the other plane 12 of the matte as shown in fig. 1 and 2 opposite to the matte 11. Therefore, the anti-fouling layer is formed as the anti-fouling layer 2 contained in the matte tempered protective glass, and is not described again for the sake of brevity. The method for forming the antifouling layer 2 may be a conventional method for forming an antifouling layer.
Therefore, the preparation method of the matte toughened protective glass firstly carries out matte processing treatment on one surface of the glass substrate and then carries out multiple toughening treatment on the glass substrate with the matte surface, so that on one hand, the prepared matte toughened protective glass has high mechanical strength on the basis of having the matte surface; on the other hand, the preparation method has easily controlled process conditions, can effectively ensure the stability of high mechanical properties of the prepared matte toughened protective glass, and has high haze transmittance and high haze.
On the other hand, based on the above-mentioned matte toughened protective glass and the preparation method thereof, the matte toughened protective glass not only has high mechanical strength, but also has high haze transmittance and haze, and in addition, the preparation method can also ensure stable performances of the mechanical strength, the haze transmittance and the like of the matte toughened protective glass, so that the matte toughened protective glass can be applied to preparation of two-dimensional code protection devices, instrument display protection devices, display advertisement screens and exhibition reading protection screens. In a specific embodiment, when the matte toughened protective glass is applied to the preparation of a two-dimensional code protective device, specifically, a two-dimensional code pattern is attached to or printed on a matte 11 of the matte toughened protective glass, and the opposite other surface 12 of the matte toughened protective glass or the opposite other surface to which the antifouling layer 2 is further bonded serves as an outer surface for code scanning. Thus, the matte 11 has high haze transmittance and haze and high myopia transmittance, so that the matte toughened protective glass can effectively avoid light reflection and poor halo caused by a flash lamp, and the code scanning speed and success rate are ensured. On the other hand, the high mechanical strength of the matte toughened protective glass endows the two-dimensional code protection device with high strength, impact resistance and breakage resistance. The existence of the antifouling layer 2 further ensures that the two-dimensional code protection device, the exhibition and reading protection screen (such as picture frame protection glass, murals, picture protection glass and the like) and the display advertisement screen and the like are kept clean, and the pollution of water stain and oil stain can be effectively avoided, so that the protection device or the protection screen has high light transmittance and efficient anti-glare property while having high strength, impact resistance and damage resistance, and the readability and observability are enhanced.
The invention is further illustrated by the following specific examples of the matte toughened protective glass and the preparation method thereof.