Colored glass panel with reduced lithium feldspar crystals and method of forming the same

Abstract

This document discloses embodiments of a colored glass panel. The colored glass panel comprises a glass body having a first main surface and a second main surface opposite to the first main surface. The glass body is made of an alkali aluminosilicate glass composition containing Li₂O. At least one of the first main surface or the second main surface has a length and a width, and the length and the width define an area. The ratio of the spodumene crystal area to the total area is 2% or less. Furthermore, for at least one wavelength in the range of about 380 nm to about 750 nm, the transmittance from the first main surface through the glass panel to the second main surface is less than about 92%.

Description

[0001] Cross-reference of related applications

[0002] This application claims priority to U.S. Provisional Application Serial No. 63 / 617971, filed January 5, 2024, pursuant to 35 USC §119, the contents of which are used as the basis and are incorporated herein by reference in their entirety. Background Technology

[0003] This disclosure relates to glass panels, and more particularly, to glass panels configured to exhibit coloration after heat treatment.

[0004] Glass is incorporated into various consumer electronics devices, particularly those including displays. This glass is partly designed to protect the display, and ion-exchangeable glass (such as alkali aluminosilicate glass) is frequently used due to its drop and impact resistance. Furthermore, glass is aesthetically desirable from both a visual and tactile perspective. For this reason, glass is also incorporated into the non-display components of consumer electronics devices, and for these applications, the tinting of the glass is desirable. Summary of the Invention

[0005] According to a first aspect, embodiments of this disclosure relate to a colored glass panel. The colored glass panel includes a glass body comprising a first main surface and a second main surface opposite to the first main surface. The glass body comprises an alkali aluminosilicate glass composition containing Li₂O. At least one of the first main surface or the second main surface contains a spodumene crystal ratio equal to or less than about 5%, for example, equal to or less than about 4%, equal to or less than about 3%, or equal to or less than about 2%. Furthermore, for at least one wavelength in the range of about 380 nm to about 750 nm, the transmittance from the first main surface through the glass panel to the second main surface may be less than about 92%.

[0006] According to a second aspect, embodiments of this disclosure relate to an electronic device comprising a housing. The housing includes a colored glass panel according to a first aspect.

[0007] According to a third aspect, embodiments of this disclosure relate to a method for preparing a colored glass panel. In this method, the glass panel is pretreated. The glass panel comprises a first main surface, a second main surface opposite to the first main surface, and a glass body disposed between the first main surface and the second main surface. The glass panel comprises an alkali aluminosilicate glass composition containing Li₂O. The pretreatment may remove or alter at least one of the first main surface or the second main surface up to a depth of 50 µm in the glass body. Furthermore, in this method, the glass panel may be heat-treated after the pretreatment at a temperature in the range of 500°C to 700°C for 1 hour to 20 hours. The heat treatment causes the transmittance from the first main surface through the glass panel to the second main surface to change from at least about 92% for all wavelengths in the range of about 380 nm to about 750 nm to less than about 92% for at least one wavelength in the range of about 380 nm to about 750 nm.

[0008] Additional features and advantages will be set forth in the detailed description below, and will be apparent in part from the description or recognized by practice of the embodiments described herein, including the detailed description below, the claims and the drawings.

[0009] It should be understood that both the foregoing general description and the following detailed description are merely exemplary and are intended to provide an overview or framework for understanding the nature and characteristics of the claims. Attached Figure Description

[0010] The accompanying drawings are included to provide further understanding and are incorporated in and constitute a part of this specification. The drawings illustrate one or more embodiments and, together with the description, serve to explain the principles and operation of various embodiments. In the drawings:

[0011] Figure 1 A colored glass panel according to one or more exemplary embodiments is depicted;

[0012] Figure 2 This is a flowchart of a method for preparing a colored glass panel according to one or more exemplary embodiments;

[0013] Figure 3 It is a glass article according to one or more exemplary embodiments, particularly a consumer electronic device comprising a colored glass panel;

[0014] Figure 4 It is a table providing images of heat-treated glass specimens according to one or more exemplary embodiments, including three specimens: a control and a pretreated specimen;

[0015] Figure 5 yes Figure 4 The chart shown represents the number of spodumene crystals per unit sample area of ​​the sample.

[0016] Figure 6 yes Figure 4 A graph showing the size of the spodumene crystals in the sample.

[0017] Figure 7 It is a table providing images of heat-treated glass specimens according to one or more exemplary embodiments, including six specimens for comparison and pretreatment;

[0018] Figure 8 yes Figure 7 The graph shown represents the number of spodumene crystals per unit area of ​​the sample; and

[0019] Figure 9 yes Figure 7 A graph showing the size of the spodumene crystals in the sample. Detailed Implementation

[0020] Various embodiments of colored glass panels with reduced spodumene crystal growth and methods for forming such colored glass panels will now be described in detail, examples of which are shown in the accompanying drawings. The glass panels disclosed herein comprise an alkali aluminosilicate glass composition, and coloring is initiated in the glass panel through heat treatment. The colored glass panels can then be incorporated as decorative elements into various consumer electronics devices, architectural structures, or automotive applications. However, in some cases, this heat treatment may cause spodumene crystals to form on the surface of the glass panel, particularly at the temperatures and times required for consistent coloring, which may render the glass panel unusable as a decorative element.

[0021] According to this disclosure, a glass panel is pretreated prior to heat treatment by removing or altering the surface of the glass panel near its surface. This removal or alteration of the glass surface can be achieved through etching, leaching, or polishing. Specifically, etching and polishing the glass panel can reduce surface roughness, remove sharp peaks and / or surface contaminants that may serve as nucleation sites for spodumene crystals, while leaching can remove lithium oxide (Li₂O) from the surface region of the glass panel and inhibit the formation of spodumene crystals on its surface. In this way, pretreatment can significantly reduce the number and size of spodumene crystals that can be produced by subsequent heat treatment, thereby allowing the glass panel to be heat-treated at the desired temperature for the required time to produce a consistent color. These and other aspects and advantages of the disclosed colored glass panel and its forming method will be described more fully below. The embodiments discussed herein are presented by way of illustration and not limitation.

[0022] Figure 1 An embodiment of a glass panel 100 according to the present disclosure is depicted. The glass panel 100 includes a glass body 102 having a first main surface 104 and a second main surface 106 opposite to the first main surface 104. Figure 1 As shown, the first primary surface 104 and the second primary surface 106 may be substantially flat. However, in one or more other embodiments, either or both of the first primary surface 104 and the second primary surface 106 may include curvature. A secondary surface 108 extends around the periphery of the glass panel 100 and connects the first primary surface 104 to the second primary surface 106. The first primary surface 104 and the second primary surface 106 define a thickness T of the glass panel 100 therebetween. In one or more embodiments, the thickness T may be in the range of about 2 mm to about 3 mm, for example, in the range of about 2.2 mm to about 3 mm, in the range of about 2.4 mm to about 3 mm, in the range of about 2.6 mm to about 3 mm, in the range of about 2.8 mm to about 3 mm, in the range of about 2 mm to about 2.8 mm, in the range of about 2 mm to about 2.6 mm, in the range of about 2 mm to about 2.4 mm, in the range of about 2 mm to about 2.2 mm, including all ranges and subranges therebetween. In some embodiments, the thickness T may be in the range of about 2.65 mm to about 2.85 mm.

[0023] The glass body 102 comprises an alkali aluminosilicate glass composition containing lithium oxide (Li2O), which facilitates the formation of spodumene crystals (LiAl(SiO3)2 crystals) in the glass panel 100. Examples of such alkali aluminosilicate glass compositions include an amount of SiO2 ranging from about 40 mol% to about 80 mol%, for example, in the range of about 50 mol% to about 80 mol%, in the range of about 60 mol% to about 80 mol%, in the range of about 70 mol% to about 80 mol%, in the range of about 50 mol% to about 70 mol%, or in the range of about 50 mol% to about 60 mol%, including all ranges and subranges therein.

[0024] The vitreous body may also contain Al2O3 in amounts ranging from 0 mol% to about 25 mol%, for example in the range of about 5 mol% to about 25 mol%, in the range of about 10 mol% to about 25 mol%, in the range of about 15 mol% to about 25 mol%, in the range of about 20 mol% to about 25 mol%, in the range of about 0 mol% to about 20 mol%, in the range of about 0 mol% to about 15 mol%, in the range of about 0 mol% to about 10 mol%, or in the range of about 0 mol% to about 5 mol%, including all ranges and subranges therein.

[0025] The vitreous body may also contain an amount of R2O ranging from about 1 mol% to about 35 mol%, wherein the R2O comprises Li2O and at least one of Na2 or K2O. For example, the vitreous body may contain R2O in the following ranges: from about 1 mol% to about 30 mol%, from about 1 mol% to about 25 mol%, from about 1 mol% to about 20 mol%, from about 1 mol% to about 15 mol%, from about 1 mol% to about 10 mol%, from about 1 mol% to about 5 mol%, from about 5 mol% to about 35 mol%, from about 10 mol% to about 35 mol%, from about 15 mol% to about 35 mol%, from about 20 mol% to about 35 mol%, from about 25 mol% to about 35 mol%, or from about 30 mol% to about 35 mol%, including all ranges and subranges therein.

[0026] In one or more embodiments, the glass composition may contain Al₂O₃ in an amount ranging from about 7 mol% to about 20 mol%, Li₂O in an amount ranging from about 1 mol% to about 20 mol%, and Na₂O in an amount ranging from about 5 mol% to about 34 mol%. In one or more embodiments, the glass composition may also contain B₂O₃ in an amount ranging from 0 mol% to about 10 mol%, K₂O in an amount ranging from 0 mol% to about 3 mol%, MgO in an amount ranging from 0 mol% to about 8.5 mol%, ZnO in an amount ranging from 0 mol% to about 2 mol%, P₂O₅ in an amount ranging from 0 mol% to about 10 mol%, CaO in an amount ranging from 0 mol% to about 1.5 mol%, Rb₂O in an amount ranging from 0 mol% to about 20 mol%, and Cs₂O in an amount ranging from 0 mol% to about 20 mol%. Other oxides may also exist, such as SrO, BaO, and ZrO2.

[0027] In one or more embodiments, the alkali aluminosilicate glass composition may be doped with at least one of the following: Au, Ag, Cu, Ni, Co, Fe, Mn, Cr, V, Ti, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, or Lu, and said at least one may be added to produce the desired coloring of the glass panel 100 upon heat treatment. In one or more embodiments, the dopant may be at about 10 -6 The coloring is provided in amounts ranging from approximately mol% to about 10 mol%. This coloring can be any of a variety of hues, including red, orange, yellow, green, blue, or purple. Examples of alkali aluminosilicate glass compositions including dopants and heat treatments for producing the desired color can be found in International Publication No. WO2022266405A1 (“Colored glass articles having improved mechanicaldurability”, filed June 17, 2022, published December 22, 2022).

[0028] In one or more embodiments, heat treatment of the glass panel 100 transforms the glass panel from a clear state to a colored state. In one or more embodiments, the coloring can be described by the transmittance of visible light from the first primary surface 104 through the glass panel 100 to the second primary surface 106. In one or more embodiments, when measured with a Konica Minolta CM 3700 spectrophotometer, the transmittance of visible light in the clear state can be at least 92% across all wavelengths in the range of about 380 nanometers (nm) to about 750 nm. In one or more embodiments, when measured with a Konica Minolta CM 3700 spectrophotometer, the transmittance in the colored state can be less than 92% for at least one wavelength in the range of about 380 nm to about 750 nm, particularly in the range of about 10% to about 92%.

[0029] In one or more embodiments, the shading can be described using the CIE L*a*b* color space. In such embodiments, the glass panel 100 may have an L* parameter in the range of about 55 to about 96.5. Furthermore, in one or more embodiments, the glass panel 100 may have an a* parameter with an absolute value of at least about 0.3 (e.g., |a*| ≥ 0.3), and in one or more embodiments, the glass panel 100 may have an a* parameter with an absolute value of at most about 60 (e.g., |a*| ≤ 60). In one or more embodiments, the glass panel 100 may have a b* parameter with an absolute value of at least about 0.5 (e.g., |b*| ≥ 0.5), and in one or more embodiments, the glass panel 100 may have a b* parameter with an absolute value of at most about 90 (e.g., |b*| ≤ 90). Furthermore, at least one of a* or b* may be non-zero. In one or more of the foregoing embodiments, the L*, a*, and b* parameters can be measured under F2 illumination and a 10° standard observer angle. Color measurements were performed using a Konica Minolta CM 3700 spectrophotometer.

[0030] As described above, heat-treating the glass panel 100 to initiate coloring can cause spodumene crystals to form on or near the first main surface 104 and / or the second main surface 106. If the number of spodumene crystals is too large or the size of the spodumene crystals is too large, the glass panel 100 may become unusable for decorative purposes because the spodumene crystals may be visible to the naked eye. According to this disclosure, the glass panel 100 can be pretreated before heat treatment to reduce the number and size of spodumene crystals by removing nucleation sites for spodumene crystal formation or reducing the amount of lithium oxide available for forming the spodumene crystals.

[0031] like Figure 1As shown, the glass panel 100 may be rectangular, comprising a length L and a width W. Therefore, the area of ​​the glass panel is the product of the length L and the width W. However, in other embodiments, the glass panel 100 may be of different shapes, such as any of various curved or polygonal shapes, or a shape comprising both curved edges and straight edges. The first main surface 104 and / or the second main surface 106 also include a sample region 105 comprising a length L1 and a width W1. Figure 1 The sample region is shown as a rectangle having a region defined by the product of length L1 and width W1. However, like the glass panel 100, the sample region 105 can have other shapes, and its area can be determined by appropriate geometric formulas. The sample region 105 can have an area (e.g., L1 × W1) equal to or less than the total area (e.g., L × W) of the first main surface 104 or the second main surface 106. In an embodiment, the sample region can have an area equal to or greater than 2500 mm. 2 The area of ​​the spodumene crystals within sample region 105 can be equal to or less than about 0.05, for example, equal to or less than about 0.04, equal to or less than about 0.03, or equal to or less than about 0.02. That is, for example, the total area of ​​the spodumene crystals can be equal to or less than about 5% of the total area of ​​the sample region. In one or more embodiments, the ratio of the area of ​​the spodumene crystals within sample region 105 to the total area of ​​sample region 105 can be equal to or less than about 0.01. Furthermore, in one or more embodiments, the spodumene crystals can have an average size of 20 µm or less, where size refers to the maximum dimension of the spodumene crystal. In one or more embodiments, the spodumene crystals can contain 110 spodumene crystals / mm. 2 The surface area of ​​the first and / or second principal surfaces is less than 110 spodumene crystals / mm². 2 The number density. In one or more embodiments, eliminating all spodumene crystals may be impossible, and therefore, at least 1 spodumene crystal / mm² may be present in the glass panel 100. 2 In contrast, glass panels prepared without pretreatment can contain up to 600 spodumene crystals per mm. 2 Or more, and / or include spodumene crystals covering more than 5% of the area of ​​the first primary surface and / or the second primary surface.

[0032] The glass panel 100 after heat treatment has been described, and now a method for preparing the glass panel 100 will be discussed, which involves pretreating the glass panel 100 before heat treatment. Figure 2 A flowchart of a method 200 for preparing a glass panel 100 is provided, and Figure 2 relative to Figure 1The glass panel 100 is discussed for reference. In the first step 201 of method 200, the glass panel 100 is pretreated to remove or alter at least one of the first main surface 104 or the second main surface 106 up to a depth D of 50 µm in the glass body 102. As described above, pretreatment of the glass panel 100 can remove nucleation sites for the formation of spodumene crystals from the first main surface 104 and / or the second main surface 106 of the glass panel 100, and / or deplete lithium oxide (Li2O) from the surface regions to limit the formation of spodumene crystals. In the second step 202 of method 200, the glass panel 100 is then heat-treated at a temperature in the range of 500°C to 700°C for 1 hour to 20 hours to change the glass panel 100 from a substantially transparent or clear state to a state in which the glass panel 100 exhibits coloration.

[0033] The pretreatment in step 201 can be performed in a variety of suitable ways. In one or more embodiments, the first step 201 of the pretreatment involves etching the glass panel 100 to remove surface defects and reduce surface roughness. In one or more such embodiments, etching involves exposing at least one of a first main surface 104 or a second main surface 106 to an etchant. In such embodiments, the etchant can be acidic or alkaline.

[0034] In one or more embodiments involving an acidic etchant, the etchant may contain about 1 wt% to about 20 wt% hydrofluoric acid. Furthermore, in one or more such embodiments, the acidic etching is performed at room temperature, or may be performed at a high temperature. For example, in one or more embodiments, the acidic etching may be performed at a temperature ranging from about 20°C to about 45°C.

[0035] In one or more embodiments involving an alkaline etchant, the alkaline etchant may contain at least one of about 10 wt% to about 70 wt% of NaOH or KOH. In one or more such embodiments, the alkaline etching may be performed at a high temperature (e.g., in the range of about 90°C to about 165°C).

[0036] In one or more embodiments, whether acidic or alkaline etching, the etching process can be carried out for a time sufficient to remove approximately 1 micrometer (µm) to approximately 50 µm from at least one of the first main surface 104 or the second main surface 106. In one or more embodiments, acidic etching can be carried out for at least approximately 5 minutes. In one or more embodiments, acidic etching can be carried out for up to approximately 180 minutes. In one or more embodiments, alkaline etching can be carried out for at least approximately 10 minutes. In one or more embodiments, alkaline etching can be carried out for up to approximately 180 minutes.

[0037] Following etching, in one or more embodiments, the etched first primary surface and / or second primary surface may exhibit a surface roughness S of approximately 80 nm or less, as measured according to ISO 25178. a , where parameter Sa refers to the arithmetic mean height of a surface area with a finite scale.

[0038] By using etching as a pretreatment, surface contaminants are removed, and the surface is essentially free of sharp defects and blemishes that could provide nucleation sites for the formation of spodumene crystals.

[0039] In one or more embodiments, the first step 201 of the pretreatment involves polishing at least one of the first main surface 104 or the second main surface 106. In one or more such embodiments, polishing removes about 5 µm to about 40 µm from at least one of the first main surface 104 or the second main surface 106.

[0040] In one or more embodiments, polishing can be performed by grinding at least one of the first primary surface 104 or the second primary surface 106 with a slurry (e.g., an aqueous slurry) containing polishing particles (such as rare earth oxide particles). Polishing can be performed by chemical mechanical polishing and related equipment. In one or more embodiments, the polishing particles may contain a median particle size (D50) in the range of about 2.3 µm to about 3.6 µm. In one or more embodiments, the polishing particles may contain cerium dioxide as a major component. Such rare earth oxide polishing particles, especially those with high cerium dioxide content, are known to provide good surface finish, allow for fast polishing speeds, and have a long service life. However, in one or more other embodiments, other abrasive particles may be used instead of or in combination with rare earth oxide polishing particles.

[0041] In one or more embodiments, after polishing, the polished first primary surface 104 or second primary surface 106 may contain a surface roughness Sa of about 10 nm or less when measured according to ISO 25178. Similar to etching, pretreatment by polishing can remove surface contaminants and produce a surface substantially free of sharp defects and imperfections that could provide nucleation sites for spodumene crystal formation.

[0042] In one or more embodiments, the first step 201 of the pretreatment involves exposing the glass panel 100 to an acidic leaching agent. In one or more such embodiments, the acidic leaching agent may comprise at least one of about 1 wt% to about 20 wt% of HCl, H2SO4, or HNO3, such as about 2 wt% to about 20 wt%, about 5 wt% to about 20 wt%, about 10 wt% to about 20 wt%, or about 15 wt% to about 20 wt% of HCl, H2SO4, or HNO3. In one or more embodiments, the glass panel 100 may be exposed to the acidic leaching agent at a high temperature, such as a temperature in the range of about 40°C to about 95°C (e.g., about 50°C to about 95°C, about 60°C to about 95°C, about 70°C to about 95°C, or about 80°C to about 95°C, including all ranges and subranges therein). In one or more embodiments, the glass panel 100 may be exposed to an acidic leaching agent for a duration ranging from about 30 minutes to about 180 minutes (e.g., about 40 minutes to about 180 minutes, about 60 minutes to about 180 minutes, about 80 minutes to about 180 minutes, about 100 minutes to about 180 minutes, about 120 minutes to about 180 minutes, about 140 minutes to about 180 minutes, or about 169 minutes to about 180 minutes, including all ranges and subranges therein).

[0043] In one or more embodiments, after the glass panel 100 is exposed to an acidic leaching agent, the first Li2O concentration in the region from the first main surface 104 and / or the second main surface 106 to a depth D of about 100 nm may be less than the second Li2O concentration at the midpoint of the thickness T of the glass body 102 between the first main surface 104 and the second main surface 106.

[0044] As described above, spodumene crystals contain lithium (LiAl(SiO3)2), and therefore, by leaching lithium from the surface region of the glass panel 100, less lithium can be used to form spodumene crystals.

[0045] The stained glass panel 100 described herein can be used in a variety of applications, including, for example, housings for consumer electronic devices; architectural glass applications; automotive or vehicle glass applications; or commercial or household appliance applications. In one or more embodiments, consumer electronic devices (e.g., smartphones, tablets, watches, personal computers, ultrabooks, televisions, and cameras), architectural glass, and / or automotive glass may include the stained glass panel 100 as described herein.

[0046] Figure 3 Example articles containing any of the colored glass panels 100 disclosed herein are shown. Specifically, Figure 3A consumer electronic device 300 is illustrated, comprising a housing 302 having a front surface 304, a rear surface 306, and a side surface 308; electrical components (not shown) at least partially or entirely within the housing 302, including, for example, a controller, memory, and a display 310 located at or adjacent to the front surface of the housing 302; and a cover plate substrate 312 located at or above the front surface of the housing 302 such that it is positioned above the display. In one or more embodiments, at least a portion of the housing 302, such as the back 306, may comprise any of the colored glass panels of the colored glass panel 100 disclosed herein.

[0047] Experimental Example

[0048] Example 1

[0049] Several glass specimens (50 mm × 50 mm) with an alkali aluminosilicate glass composition were prepared. The transverse dimensions of the glass specimens were 50 mm × 50 mm. All glass specimens were heat-treated at 600 °C for 6 hours. According to existing practice, the first type of glass specimen was not pretreated and was used as a control to provide a comparison of the amount of spodumene crystals caused by heat treatment. The remaining glass specimens were pretreated according to the three pretreatments described in this disclosure. Specifically, the second type of glass specimen was alkaline etched at 120 °C with 50% NaOH for 40 minutes to remove approximately 10 µm from each of the opposite main surfaces of the specimen. The third type of glass specimen was acid-leached at 40 °C with HNO3 (1 mol / L) for 60 minutes on each main surface, and the fourth type of glass specimen was polished on each main surface to remove approximately 2 µm from the opposite main surface. Figure 4 Examples of each type of glass specimen after heat treatment and under optical microscopy at 50x magnification are described. It can be seen that the first type of glass specimen (control) exhibits significantly more spodumene crystals than the pretreated specimen.

[0050] Figure 5 A graph showing the number of spodumene crystals after heat treatment is provided. The spodumene crystals were counted at magnification. The spodumene crystals were counted in 2 to 5 regions (each region being approximately 300 µm × 300 µm) on each sample specimen in the sample specimens (1 to 5 specimens of each type). Figure 5A box plot is provided showing the number of spodumene crystals counted in each region of the heat-treated glass specimens. It can be seen that the average number of spodumene crystals per unit area in the first type of glass specimen without pretreatment is significantly higher than the average number of spodumene crystals per unit area in any of the specimens according to any of the three pretreatment types. Specifically, the first type (control) glass specimen exhibits an average of approximately 50 spodumene crystals per unit area, while the second, third, and fourth type glass specimens exhibit fewer than an average of approximately 25 spodumene crystals per unit area. Therefore, all three pretreatment methods are effective in reducing the number of spodumene crystals.

[0051] Figure 6 A chart summarizing the sizes of spodumene crystals detected at various magnifications for four types of glass samples is provided. Specifically, Figure 6 Box plots showing the size of spodumene crystals are provided. It can be seen that the average crystal size of the pretreated glass samples of types two, three, and four is reduced. Specifically, the type one glass sample (control) exhibits spodumene crystals with an average size of approximately 40 µm. The type two, three, and four glass samples all exhibit spodumene crystals with an average size of less than 35 µm.

[0052] from Figure 5 and 6 It can be seen that, in this set of experiments, alkaline etching produced the best overall results in terms of reducing the average number of spodumene crystals (approximately 5 per unit area) and the average size of spodumene crystals (less than 20 µm on average). However, it can also be seen that acid leaching also reduced the average number of spodumene crystals to approximately the same level as alkaline etching.

[0053] Example 2

[0054] Several additional glass samples of alkali aluminosilicate glass were prepared. All glass samples were heat-treated at 600 °C for 6 hours. According to existing practice, the first type of glass sample was not pretreated and was used as a control for comparison with the pretreated glass sample. The second, third, fourth, and fifth types of glass samples were alkaline etched at 120 °C using a 50% NaOH aqueous solution. The second type of glass sample was etched to remove approximately 1 µm from the main surface, and the third type was etched to remove approximately 5 µm from the main surface. The fourth type was etched to remove approximately 10 µm, and the fifth type was etched to remove approximately 20 µm. The sixth and seventh types of glass samples were polished to remove approximately 10 µm and approximately 20 µm from the main surface, respectively.

[0055] Figure 7 Examples of each type of glass specimen, after heat treatment and under 50x magnification using an optical microscope, are depicted. It can be seen that the first type of glass specimen (control) includes several visible spodumene crystals. The second through seventh types of glass specimens all exhibit significantly fewer visible spodumene crystals. Furthermore, for the glass specimens treated with alkaline etching, the number of visible spodumene crystals decreases with increasing etching depth. Similarly, the number of visible spodumene crystals decreases with increasing polishing depth.

[0056] Figure 8 A graph showing the number of spodumene crystals after heat treatment is provided. As in Example 1, the spodumene crystals were counted at magnification, and the crystals were counted in 2 to 5 regions (each region being approximately 300 µm × 300 µm) on 2 to 5 samples of each type. Figure 8 A box plot showing the number of spodumene crystals in each type of glass sample is provided. From Figure 8 As can be seen, for the first type of glass sample (control), the average number of spodumene crystals per unit area is 30, while for the second to seventh types of glass samples, the average number of spodumene crystals per unit area is less than 15. For the third to seventh types of glass samples, the average number of spodumene crystals per unit area is less than 5. Therefore, the number of spodumene crystals can be reduced by removing only 1 µm from the surface of the glass.

[0057] Figure 9 A chart summarizing the sizes of spodumene crystals detected at various magnifications for seven types of glass samples is provided. Specifically, Figure 9 Box plots of spodumene crystal size are provided. It can be seen that the average size of the spodumene crystals in the pretreated glass samples is reduced. Specifically, the first type of glass sample (control) exhibits spodumene crystals with an average size (average of maximum size) of approximately 13 µm. The second through seventh types of glass samples all exhibit spodumene crystals with an average size of less than approximately 10 µm.

[0058] from Figure 8 and 9 It can be seen that in this set of experiments, both alkaline etching and polishing are effective in reducing the average number of spodumene crystals (15 or fewer per unit area) and the average size of spodumene crystals (less than about 10 µm on average), especially when removing spodumene crystals with a size greater than about 5 µm from the surface (5 or fewer spodumene crystals per unit area on average and spodumene crystals with an average size less than about 10 µm on average).

[0059] Example 3

[0060] Image analysis was performed on seven example glass specimens (50 mm × 50 mm) prepared according to Example 2 and an example acid leaching specimen according to Example 1 to determine the total area of ​​spodumene crystals on the pretreated glass surface. Images of a defined sample region 105 were obtained from the glass specimens using a polarizing polarizer and a camera. The sample region images were first converted to grayscale, with each pixel of the grayscale image having a value on a scale from 0 to 255, where 0 represents black and 255 represents white. The images were then converted to black and white images, where pixels with values ​​equal to or less than 200 were rendered as black pixels, and pixels with values ​​greater than 200 were rendered as white pixels. Using image analysis software, the total number of pixels in the image (white pixels plus black pixels) and the total number of white pixels were counted. The size (area) of each pixel was determined from the sensor characteristics of the imaging device (e.g., camera), and the “spodumene crystal area” (SCR) was calculated as the total area of ​​all white pixels in the sample region divided by the total area of ​​the sample region, expressed as a percentage. The SCR of the sample region can be used to represent the SCR of the glass specimen surface. Table 1 provides a summary of the image analysis.

[0061] Table 1: Spodumene crystal ratio of samples with and without various pretreatments

[0062]

[0063] Therefore, as shown in Table 1, the pretreatment reduces the spodumene crystal ratio (SCR) from 6.02% to below 5%. Specifically, for etching and polishing pretreatments, the SCR is reduced to below 2%, particularly to about 1% or lower.

[0064] Unless otherwise expressly stated, it is not intended to interpret any method described herein as requiring its steps to be performed in a particular order. Therefore, no particular order is intended to be inferred unless a method claim actually describes the order in which its steps are performed, or unless the claims or specification otherwise specifically state that the steps are restricted to a particular order. Furthermore, as used herein, the article “a(a)” is intended to include one or more parts or elements and is not intended to be construed as referring to only one.

[0065] It will be apparent to those skilled in the art that various modifications and variations can be made without departing from the spirit or scope of the disclosed embodiments. Since modifications, combinations, sub-combinations, and variations of the disclosed embodiments incorporated into the spirit and spirit of the embodiments will be apparent to those skilled in the art, the disclosed embodiments should be construed as including all contents within the scope of the appended claims and their equivalents.

Claims

1. A colored glass panel comprising: A glass body comprising a first primary surface and a second primary surface opposite to the first primary surface, the glass body comprising an alkali aluminosilicate glass composition containing Li₂O; and Wherein at least one of the first primary surface or the second primary surface comprises a spodumene crystal ratio equal to or less than about 0.02; and For at least one wavelength in the range of 380 nm to 750 nm, the transmittance from the first main surface through the glass panel to the second main surface is less than 92%.

2. The colored glass panel of claim 1, wherein the spodumene crystals have an average size of 20 µm or less.

3. The colored glass panel according to claim 1 or claim 2, wherein the spodumene crystal comprises 110 spodumene crystals / mm². 2 Or even less quantity density.

4. The stained glass panel according to any one of claims 1 to 3, wherein, according to the CIE L*a*b* color space, as measured under F2 illumination and a standard observer angle of 10°, the glass panel contains an L* parameter in the range of 55 to 96.5, and at least one of an a* parameter having an absolute value of at least 0.3 or a b* parameter having an absolute value of at least 0.

5.

5. The colored glass panel according to any one of claims 1 to 4, wherein at least one of the first main surface or the second main surface comprises an average surface roughness S having a value of 10 nm or less. a Polished surface.

6. The colored glass panel according to any one of claims 1 to 4, wherein the first Li2O concentration in a region from at least one of the first main surface or the second main surface to a depth of about 100 nm is lower than the second Li2O concentration at the midpoint of the thickness of the glass body between the first main surface and the second main surface.

7. The colored glass panel according to any one of claims 1 to 4, wherein at least one of the first main surface or the second main surface comprises an average surface roughness S having an average surface roughness of 80 nm or less. a The etched surface.

8. The colored glass panel according to any one of claims 1 to 7, wherein the spodumene crystal ratio is equal to or less than about 2%.

9. The colored glass panel according to any one of claims 1 to 8, wherein the alkali aluminosilicate glass composition is doped with at least one of the following: Au, Ag, Cu, Ni, Co, Fe, Mn, Cr, V, Ti, La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, and Lu.

10. An electronic device comprising a housing, the housing including a colored glass panel according to any one of claims 1 to 9.

11. A method for preparing a colored glass panel, the method comprising: A glass panel is pretreated, the glass panel comprising a first main surface, a second main surface opposite to the first main surface, and a glass body disposed between the first main surface and the second main surface, the glass panel comprising an alkali aluminosilicate glass composition containing Li2O, wherein the pretreatment removes or alters at least one of the first main surface or the second main surface up to a depth of 50 µm in the glass body; and Following the pretreatment, the glass panel is heat-treated at a temperature ranging from about 500°C to about 700°C for 1 hour to 20 hours, the heat treatment causing the transmittance from the first main surface through the glass panel to the second main surface to change from at least 92% for all wavelengths in the range of 380 nm to 750 nm to less than 92% for at least one wavelength in the range of 380 nm to 750 nm.

12. The method of claim 11, wherein the pretreatment comprises etching the glass panel.

13. The method of claim 12, wherein the etching further comprises exposing at least one of the first primary surface or the second primary surface to an etchant comprising about 1 wt% to about 20 wt% of hydrofluoric acid.

14. The method of claim 13, wherein the etching is performed at a temperature in the range of 20°C to 45°C.

15. The method of claim 12, wherein the etching further comprises exposing at least one of the first primary surface or the second primary surface to an etchant comprising at least one of about 10 wt% to about 70 wt% of NaOH or KOH.

16. The method of claim 15, wherein the etching is performed at a temperature in the range of 90°C to 165°C.

17. The method according to any one of claims 12 to 16, wherein the etching removes about 1 µm to about 50 µm from at least one of the first main surface or the second main surface.

18. The method of claim 11, wherein the pretreatment comprises polishing at least one of the first main surface or the second main surface.

19. The method of claim 18, wherein the polishing removes about 5 µm to about 40 µm from at least one of the first main surface or the second main surface.

20. The method of claim 18 or claim 19, wherein the polishing comprises grinding at least one of the first primary surface or the second primary surface with a slurry containing polishing particles.

21. The method of claim 20, wherein the polishing particles comprise a median particle size (D50) in the range of about 2.3 µm to about 3.6 µm.

22. The method of claim 20 or claim 21, wherein the polishing particles comprise cerium dioxide.

23. The method of claim 11, wherein the pretreatment comprises exposing the glass panel to an acidic leaching agent.

24. The method of claim 23, wherein the acidic leaching agent comprises at least one of about 1 wt% to about 20 wt% of HCl, H2SO4 or HNO3.

25. The method of claim 23 or claim 24, wherein the exposure of the glass panel to the acidic leaching agent is performed at a temperature in the range of 40°C to 95°C.

26. The method according to any one of claims 23 to 25, wherein the glass panel is exposed to the acidic leaching agent for a period ranging from 30 minutes to 180 minutes.

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