201029943 六、發明說明： 【發明所屬之技術領域】 本發明係關於保護性玻璃覆蓋，以及特別是關於化學 地增韌，抗損壞玻璃覆蓋而適合使用於電子裝置中。 . 【先前技術】 - 使用具有較大顯示器的行動式裝置變為更加普遍存在 於-些裝置，例如行動電話，手持遊戲機，MP3播放器，手錶， ❿筆5己型電腦，行動式GPS以及其他汽車中顯示器銀幕，觸摸 板銀幕，以及其他電子裝置而沒有受到限制。至少部份覆 蓋板為透明的，以允許使用者觀看顯示器。對於一些應用， 覆蓋板對使用者職為錄的。由於使肖魏置提高覆蓋 玻璃破裂之齡或遭受意外，清理，疏忽使肋及一般使用 之損壞亦增加。目前可彻覆蓋玻璃並未特別設計或加以 選擇以在高程度不正常使贼—钱會發生—般意外例如 尖銳接觸或與其他物體碰撞而能保存。由於頻繁接觸，例 Φ 如覆蓋板必需具有高強度以及為抗刮損。 對於現存玻璃之選擇標準，雖然並非總是加以規格化， 通常受限於下列： 1. 最小南度，當135公克球掉落於以先前方式支撐玻璃上 時將保持不受損之高度； 2. 最小強度，其以四點彎曲測試量測；以及 3. 硬度，雖然一般量測並非必需的。 使用於顯示器裝置中現存保護性玻璃並非十分為人所 熟知。除此，接受覆盍玻璃適合作為使用之主要測試方法 201029943 該韻渐胁_無_地評估玻 ’因為其對現存表面缺陷十分錄以及無法201029943 VI. Description of the Invention: TECHNICAL FIELD OF THE INVENTION The present invention relates to protective glass covering, and particularly to chemically toughened, damage-resistant glass covering suitable for use in electronic devices. [Prior Art] - Using mobile devices with larger displays becomes more ubiquitous in some devices, such as mobile phones, handheld game consoles, MP3 players, watches, pens, laptops, mobile GPS, and Display screens, touch screen screens, and other electronic devices in other cars are not limited. At least a portion of the cover is transparent to allow the user to view the display. For some applications, the overlay is for the user's job. Due to the increased age of the cover glass or the accident, cleaning, negligence increases the damage of the ribs and general use. Currently, the cover glass is not specially designed or selected to allow a thief-money to occur in a high degree of abnormality, such as sharp contact or collision with other objects. Due to frequent contact, the Φ such as the cover sheet must have high strength and be scratch resistant. The selection criteria for existing glass, although not always normalized, are usually limited to the following: 1. Minimum south, when 135 grams of ball falls to the height that will remain intact when supported on the glass in the previous manner; 2 Minimum strength, measured in four-point bending test; and 3. Hardness, although general measurements are not required. Existing protective glasses for use in display devices are not well known. In addition, the acceptance of the cover glass is suitable as the main test method for use. 201029943 This rhyme threatens _ no _ to evaluate the glass ‘ because it is very recorded and can not
:二，Ϊ °例如在離子交換後立即進行的強度測試已 為覆蓋玻璃保護能力之預期指標。這些測試將自然 ^促使人們評估在深離子交換層上絲賴應力。我們已 發現此為不正_的以及與實際情況相反。因而，目前在這 些裝置中_駿_對玻_及錢鍊置巾與磨損抵 抗性以及目視外誠接侧之離子賴雜無法最佳化。 目前使行練置中SLS玻璃由於離子交換能力本 質性限制而受到機械性阻礙。 上述所說明標準亦適用於選擇主要為石灰蘇打石夕酸趟 糸列之玻璃，包含提高礬土含量之玻璃，其稱為财酸鹽或 改良之鋁矽酸鹽玻璃。上述所提及美國第11/888213號專 利申請案揭示Λ-些_域份，其縣前肋覆蓋玻璃 配方作改善。仙魏··並不綱這錄置現場觀 察到的實際麵赋。由先前麟界定域格無法預測當 ^動襄置掉落於线物體例如小石頭上時玻魏夠承受: ：>、負載。亦無法預測玻璃在行動裝置經歷使用中表面累積 受到損壞後玻_祕持下权減。先前猶規格會導 致零件為無法接受林触度以及觸。本發明將克服目 前使用作為電子裝置中保護性覆蓋及/或接觸銀幕之破璃 中一些缺點。 【發明内容】 本發明係關於高強度化學地增韌保護性及/或交互性( 201029943 例如，觸摸銀幕)玻璃物品，當負載使用Vickers壓痕器（ i ndenter)施加於玻璃時在缺乏初始徑向裂縫量測下玻璃 物品具有至少2000公克高損壞耐受門檻值。在一項實施例中 ，南損壞对受門權值至少為4000公克。在另一項實施例中 - 高損壞耐受門檻值至少為6000公克。 . 在更進一步實施例中高強度化學地增動保護性玻璃物 品透明的。 φ 在其他實施例中高強度化學地增韌保護性玻璃物品為 不透光的及/或不透明的。 在一項實施例中本發明係關於保護性玻璃，其由蘇打 石灰玻璃，含有驗金屬銘石夕酸鹽玻璃，含有驗金屬銘硼;5夕酸 鹽玻璃製造出，其已作離子交換，當負載使用Vickers壓痕 器施加於玻璃時在缺乏初始徑向裂缝量測下玻璃物品具有 至少2000公克高損壞耐受門檻值。在一項實施例中，高損 壞耐受門檻值至少為4000公克。在另一項實施例中，高損 壞耐受門檻值至少為6〇〇〇公克。 . 本發明亦關於在使用作為保護性覆蓋片之薄的玻璃物 體中設計離子交換參數之方法，該方法具有下列步驟： 選擇所需要壓縮層之深度以達成使用Vickers壓痕器測 試量測之抗損壞及/或使用Knoop鑽石壓痕器之抗刮損所需 要數值； 選擇壓應力，其將使玻璃物品中央發展所設計最大張應 力；以及 稀釋含有鹼金屬離子之離子交換浴，鹼金屬離子直徑大 201029943 於納離子直减與_離子交換崎成所需要之壓應力。 本發明亦關於製造化學地增加強度玻璃物品之方法， 該玻璃物品適合使用作為保護性覆蓋玻璃，該方法包含下 列步驟： ' &供玻璃#’玻璃#由選自於含有驗金屬!時酸鹽玻璃， •含有鹼金屬鋁硼矽酸鹽玻璃，含有鹼金屬硼矽酸鹽玻璃以 及含有鹼金屬玻璃陶瓷群組之玻璃製造出； _ 藉由離子交換玻璃表面中Na及/或Li離子以較大鹼金屬 離子（或其他較大可交換離子）化學地增加玻璃片強度，由 玻璃片表面化學交換深度至少為4〇微米；以及 藉由切割及拋光修飾玻璃片為所需要程度（包括以及邊 緣切割，研磨以及拋光）以製造出玻璃物品； 其中當修飾時，當負載使用Vickers壓痕器施加於玻璃時 在缺乏初始徑向裂縫量測下玻璃物品具有至少2〇〇〇公克高 損壞耐受門檻值。 φ 【實施方式】 如在此所使用，所謂"化學增加強度”，”化學增辆”以及 π離子交換"，以及類似名詞係指玻璃組成份中鹼金屬離子 與較大直徑鹼金屬離子作交換。在此所列舉所有玻璃組成 份為任何離子交換前之玻璃。人們了解申請專利玻璃物品 為保護性及/或交互性例如觸摸銀幕。如圖8_11所使用，箭 頭200表示刮傷方向。如在此所使用關於玻璃組成份，所謂 ”實質上包含π係指組成份含有引述材料以及數量，以及排 除存在於玻璃中污染物。 6 201029943 本發明-般所揭示為_保護性覆蓋玻璃其已化學 地增加強度當貞做錢ekersM痕馳祕玻璃時在缺 乏初始控向裂縫量測下玻璃物品具有至少麵公克高損壞 門檻值。同時本發明能夠使用來製造任何厚度(例如為3〇 • mji)覆蓋麵，覆蓋玻璃作為使用於電子裝置中，以及特別 .是手持裳置，基於重量理由必需為薄的以及一般具有厚度 為小於或等於5. 〇mm;優先地小於或等於2. 〇mm;在一些實施 ❹例中為小於Umm;以及在其他實施例中為小於12咖。關 於薄的覆蓋玻璃困難處在於雖然為薄的，玻璃必需在使用 環境中能夠承受研磨以及亦能夠抵抗破裂，剝離以及其他 型式之損壞。由於行動顯示器製造商將現存以及未來的產 品由塑膠顯示器覆蓋轉變為玻璃覆蓋，玻璃暴露於比以往 增加不當使用程度。目前可適用於行動電話商業化離子交 換玻璃上刮損以及衝擊損壞之範例顯示於圖1及2中。圖1 顯示出保護性玻璃覆蓋上由於一般使用所發生之刮痕。圖 ❿ 2顯示出相同玻璃由於接觸尖銳物或與一物體衝擊發生之 損壞相同型式玻璃使用於其他電子裝置中。 在一項中，本發明係關於薄的離子交換(化學地增物） 覆蓋玻璃最佳化，使得其使用於行動式（或非行動）顯示器 裝置時能夠抵抗損壞以及破裂。該玻璃性能依據一些試驗 (現存或將發展)加以說明，這些試驗特別地設計來量化損 壞門檻值以及破壞抵抗性。本發明玻璃壓力層已加以最佳 化至深度至少為40微米，其比使用於這些裝置中其他離子 交換覆蓋玻璃更深，以及具有壓應力至少為700MPa。此為 201029943 縫初始形成 層深度(D0L)以及壓應力（CS)合併效果其對裂 以及破壞提供良好的抵抗性。 當最大張力強度限制施加於薄的玻璃物體，cs以及靴 必需加以限制。該關能_由_最切啊控制壓力 層之深度達成或其能簡由達成所需要DQ __最大Μ 加以控制。D0L能夠藉由控制時間加以限制同時⑺能夠藉 由控制在離子交換财鋼離子濃度加以限制。不同厚度(: Second, Ϊ ° For example, the strength test immediately after ion exchange has been the expected indicator for covering the glass protection capacity. These tests will naturally encourage people to evaluate the silk stress on the deep ion exchange layer. We have found this to be incorrect and contrary to the actual situation. Therefore, in these devices, it is currently impossible to optimize the ion resistance of the _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ At present, SLS glass is mechanically hindered due to the inherent limitation of ion exchange capacity. The above-mentioned standards are also applicable to the selection of glass which is mainly lime soda tartar, and which comprises a glass which increases the alumina content, which is called acid salt or modified aluminosilicate glass. The above-mentioned patent application No. 11/888,213, which discloses the above-mentioned _ domain, has a pre-counter rib cover glass formulation for improvement. Xian Wei·· does not outline the actual face of the scene. It is impossible to predict from the previous lining domain that when the turbulence is dropped on a line object such as a small stone, the glass is able to withstand: :>, load. It is also impossible to predict that the glass will be deducted after the surface of the mobile device is damaged during use. Previous specifications will result in parts that are unacceptable for forest touch and touch. The present invention overcomes some of the shortcomings of current use as a protective cover in an electronic device and/or a glass that contacts a screen. SUMMARY OF THE INVENTION The present invention relates to high strength chemically toughened protective and/or interactive (201029943, for example, touch screen) glass articles that lack initial path when the load is applied to the glass using a Vickers indenter (indenter) The glass article has a high damage tolerance threshold of at least 2000 grams for crack measurement. In one embodiment, the south damage pair receives a threshold of at least 4000 grams. In another embodiment - the high damage tolerance threshold is at least 6000 grams. In a further embodiment, the high strength chemically mobilizes the protective glass article to be transparent. φ In other embodiments, the high strength chemically toughened protective glass article is opaque and/or opaque. In one embodiment, the present invention relates to a protective glass made of soda lime glass, comprising a metallurgical glass, comprising a metal borax; a bismuth silicate glass, which has been ion exchanged, The glass article has a high damage tolerance threshold of at least 2000 grams in the absence of initial radial crack measurements when the load is applied to the glass using a Vickers indenter. In one embodiment, the high damage tolerance threshold is at least 4000 grams. In another embodiment, the high damage tolerance threshold is at least 6 gram. The invention also relates to a method of designing ion exchange parameters in a thin glass object using a protective cover sheet having the following steps: selecting the depth of the desired compression layer to achieve an anti-week resistance test using Vickers indenter test Damage and/or the value required for the scratch resistance of the Knoop diamond indenter; the selection of compressive stress, which will allow the development of the maximum tensile stress in the center of the glass article; and the dilution of the ion exchange bath containing alkali metal ions, the diameter of the alkali metal ion Large 201029943 The direct ion reduction and the _ ion exchange are the required compressive stress. The invention also relates to a method of making a chemically increased strength glass article suitable for use as a protective cover glass, the method comprising the steps of: & glass for glass #' Salt glass, • Contains alkali metal aluminoborosilicate glass, containing alkali metal borosilicate glass and glass containing an alkali metal glass ceramic group; _ by ion exchange of Na and/or Li ions in the glass surface Larger alkali metal ions (or other larger exchangeable ions) chemically increase the strength of the glass sheet, with a chemical exchange depth of at least 4 μm from the surface of the glass sheet; and the extent to which the glass sheet is modified by cutting and polishing (including Edge cutting, grinding, and polishing to produce a glass article; wherein when modified, when the load is applied to the glass using a Vickers indenter, the glass article has at least 2 gram high damage resistance in the absence of initial radial crack measurements. Accepted by the threshold. φ [Embodiment] As used herein, the terms "chemical increase strength", "chemical increase" and "π ion exchange", and similar terms refer to alkali metal ions and larger diameter alkali metal ions in the glass composition. For exchange, all glass components listed herein are any pre-ion exchanged glass. It is understood that the patented glass article is protective and/or interactive, such as a touch screen. As used in Figures 8-11, arrow 200 indicates the direction of the scratch. As used herein with respect to a glass component, the term "substantially encompasses π means that the component contains the recited material and the amount, as well as the exclusion of contaminants present in the glass. 6 201029943 The invention is generally disclosed as a protective cover glass which has been chemically increased in strength. When the ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek ek. At the same time, the invention can be used to fabricate any thickness (for example, 3 〇• mji) coverage, cover glass for use in electronic devices, and in particular, hand-held skirts, which must be thin for weight reasons and generally have a thickness less than Or equal to 5. 〇mm; preferentially less than or equal to 2. 〇mm; in some embodiments, less than Umm; and in other embodiments less than 12 café. The difficulty with thin cover glass is that although thin, the glass must be able to withstand the grinding in the environment of use and also resist cracking, peeling and other types of damage. As mobile display manufacturers convert existing and future products from plastic display coverage to glass coverage, glass is exposed to increased levels of misuse. Examples of scratches and impact damage that are currently applicable to mobile phones for commercial ion exchange glass are shown in Figures 1 and 2. Figure 1 shows the scratches that occur on the protective glass cover due to general use. Figure ❿ 2 shows that the same type of glass is used in other electronic devices due to contact with sharp objects or damage caused by impact from an object. In one aspect, the present invention is directed to thin ion exchange (chemically excipient) cover glass optimization such that it is resistant to damage and cracking when used in a mobile (or non-action) display device. The performance of the glass is illustrated by a number of tests (existing or to be developed) that are specifically designed to quantify the damage threshold and damage resistance. The glass pressure layer of the present invention has been optimized to a depth of at least 40 microns which is deeper than other ion exchange cover glasses used in these devices, and has a compressive stress of at least 700 MPa. This is the 201029943 seam initial formation depth (D0L) and compressive stress (CS) combined effect to provide good resistance to cracking and damage. When the maximum tensile strength limit is applied to thin glass objects, cs and boots must be limited. The Guanneng_ is controlled by the _most control of the depth of the pressure layer or its simplicity can be achieved by achieving the required DQ __maximum 。. D0L can be limited by controlling the time while (7) can be limited by controlling the ion concentration of the ion exchange. Different thickness (
500至1000微米）玻璃物體之最大張應力限制顯示於圖^以 及當CT( +央應力）為54MPa時每一厚度劃出曲線。在圖12 W數據點表示依據本發明化學地增加強度 說明）D0L/CS關係。+數據點左邊cs/D〇L數值能夠藉由 稀釋離子交換浴。 假如60微米D0L為所需要的，對於〇. 5, 〇. 7以及〇. 9物體 在玻璃物品表面發展之最大壓應力能夠分別為職52〇以 及700MPa。假如需要特定衝擊抵抗性，一般需要規定層深 度指標同時限制表面壓應力。衝擊錄與層深度相關，如 圖13中所示。在圖13巾代表利用目前商業化所使用 化子地增加強度蘇打石灰玻璃所得到結果，以及符號_c代 表利用依據本發明化學地增加強度所得到結果。合併效應 為能夠控制薄玻璃化學地增加強度參數將得到所需要損壞 抵抗性。 由易碎性觀點，我們發現玻璃中央大約lmm厚度張應力 值應該低於54MPa如同利用FSM-6000表面應力儀量測CS及 D0L計算出。該MPa數值將隨著玻璃厚度改變，由於玻璃變 201029943 薄MPa數值提高以及玻璃變厚該數值減小。 如在此所提出數據顯示，本發明化學地增韌（拎 )玻璃具有一些改善以及為高度所需要之特性。這θ些包含^ 1.由於投射玻璃表面尖銳物體產生表面碎裂為較大抵抗 性，而比目前使用於這些裝置中之其他玻璃高。 _ 2·對限制強度初始裂縫為較大抵抗性，裂縫證明存在於 具有覆蓋之現存裝置中。 φ 3.離子交換前所引起機器加工以及處理裂縫被交換層所 包封以及位於受壓狀態。此將使得最終玻璃產物更能忍受 修飾處理過程。 本發明能夠利用能夠化學地增加強度之玻璃組成份（ 其含有玻璃中能夠作離子交換之元素）。特別適合於本發 明之玻璃為含有鹼金屬之鋁矽酸鹽玻璃，含有鹼金屬之硼 矽酸鹽玻璃，含有鹼金屬之鋁硼矽酸鹽玻璃以及含有鹼金 屬之玻璃陶瓷。在優先實施例十玻璃以及玻璃陶瓷為透 φ 明的。玻璃能夠藉由離子交換化學地增加強度以及組成份 能夠向下抽拉為玻璃片。玻璃具有熔融溫度為小於大約 1650°C以及液相線黏滯係數至少為130千泊以及，在一項實 施例中’大於為250千泊。玻璃能夠在相當低溫度下作離子 交換以及達到深度至少為3〇微米。 一項範例性玻璃在離子交換之前具有組成份以莫耳百 分比表示為：64%SSi〇2$68%;12%SNa2〇S16%;8%SAl2〇3 S12%;0%SB2〇3^3%;2%SK2〇S5%;4%SlfeOS6%;以及 〇% S CaO S 5%;其中：66% S Si〇2+B2〇3+CaO S 69%; Na2〇+K2〇+ 201029943 B2〇3+MgO+CaO+SrO>l〇°/0； 5°/〇^MgO+CaO+Sr0^8°/〇; (Na2〇+ B2〇3) - A12〇3 S 2%; 2% $ Na2〇 S A12〇3 S 6%;以及 4% S (Na2〇 +K2〇)SAl2〇d0o/o。 其他範例性玻璃在離子交換之前具有組成份以重量百 分比表示包含:64-68% Si〇2,10-12% Ah〇3, 0-2% BA, 12 -15% NazO, 2-4°/〇 K2〇, 5-7% MgO, >0-1% CaO, 〇-〇. 5°/〇(As2〇3 ，Sn〇2), 〇-l%(Sb2〇3, SnOO,以及>0-l%Ti〇2。砷以及銻通 φ 常加入至玻璃組成份作為澄清劑以輔助去除玻璃中氣態雜 質。不過，砷以及錄一般視為危險性材料。因而，在一項實 施例中，玻璃實質上不含錄以及神，包含小於大約0.05%重 有益地使用非毒性成份例如錫，鹵化物，或硫酸鹽以產生澄 清效果。錫（IV)氧化物(Sn〇2)以及錫（IV)氧化物與齒化物 組合特別地有用於作為澄清劑以及能夠使用來替代先前組 成份中神以及録。 使用來製造本發明化學地增韌玻璃之玻璃組成份能夠 參.使用適當的處理過程;例如融合抽拉，細縫抽拉，滾壓片狀 物，精確壓製以及業界熟知之其他方法。優先方法為向下 抽拉法，例如融合抽拉以及細縫抽拉因為其產生具有相當 原始表面之玻璃。這些向下抽拉方法使用於大規模製造可 離子交換平板玻璃。 融合抽拉處理過程使用抽拉筒其具有溝槽以接受熔 融玻璃原料。溝槽具有頂部敞開之堰沿著溝槽長度位於溝 槽兩側。當溝槽填滿熔融材料，熔融玻璃溢流過堰體。由 於重力，熔融玻璃向下流動於抽拉筒外側表面。這些外侧 201029943 表面向下以及向魄伸，使得其在姉筒下方邊緣處結合 。兩個流動㈣表面在該邊緣處結合以融合及形成單一流 動玻璃片。融合抽拉方法提供一些優點由於兩個玻璃薄 膜流經溝槽融合在-起，所形成玻璃片外侧表面均不接觸 裝置之任何部份。因而，表面雜並不受_接觸而產生 影響。 細縫抽拉方法不同於融合抽拉方法。在此提供溶融原 ❺料玻璃至抽拉筒。抽拉筒之底部具有噴嘴之敞開細縫，其 L伸過細縫長度。熔融玻璃流動通過細縫/嘴嘴以及向下 抽拉成為連續性玻璃片通過以及進入退火區域。與融合抽 拉處理過程比較，細縫抽拉處理過程提供較薄的玻璃片，由 於只有單-玻璃片向下抽拉通過細縫，而非兩片被溶融在 一起’如在向下融合-抽拉處理過程。 為了與向下抽拉處理過程相匹配，在此驗金屬紹石夕酸 鹽玻璃說明具有高液相線黏滯係數。在一項實施例中，液 ®-相線黏滯係數至少為130千泊，以及在另-實施例中，液相 線黏滯係數至少為25〇千泊。 在項實知例中，玻璃藉由離子交換增加強度。如在 此所使用’所謂"離子交換”係指玻璃藉由玻璃製造業界所 熟^的離子交換處理過程增加強度。該離子交換處理過程 ^ 3非限概處理加熱之齡屬辦雜玻璃（或其他適 田各驗金屬玻璃）與含有離子之加熱溶液，該離子具有較大 離子半大於存在於玻啦面巾軒，目而以較大離子替 代較小離子。例如鉀離子能夠替代玻璃中鈉或鋰離子。可 201029943 加以變化，其他具有較大原子半徑之驗金屬離子例如铷 (Rb)或絶(Cs)能夠替代玻璃中較巧、金屬離子包括鉀。同 ，地’其他驗金屬鹽類例如非限制性之硫酸鹽，由素化合物 等可使用於離子處理触巾。當在此所細組成份以 -及使用100%硝酸鉀浴時通常離子交換時間以及溫度分別為 • 380-460 C及3-16小時。所需要確實時間以及溫度決定於 要作離子交換之確實玻璃組成份。在一項實施例中，向下 _ 抽拉玻璃為藉由放置玻璃於包含KN〇3熔融鹽浴中歷時預先 決定時間以達成離子交換而化學地增加強度。在一項實施 例中，、熔融鹽洛之溫度約為43(rCW及預先決定時間約為8 小時。在另一實施例中，離子交換最先使用K離子實施以達 成所需要父換深度以及再使用ce或此離子實施以更進一步 藉由相當靠近表面與K作離子交換以強化表面。 向下抽拉處理過程產生相當初始純淨之表面。因為玻 璃表面之強度藉由表面裂縫之數量以及尺寸加以控制具 Φ 有最小接觸之初始純淨表面具有較高之初始強度。當該高 強度玻璃再化學地增加強度，最終強度高於表面作重疊以 及拋光表面部份。藉由離子交換化學增加強度或回火亦提 高玻璃由於處理所導致裂縫形成之抵抗性。因而，在一項 實施例中’對於300醜x400mm玻璃片，向下抽拉鹼金屬鋁矽 酸鹽玻璃之翹曲為小於大約〇. 5麵。在另一實施例中，翹曲 為小於大約0. 3mni。 表面壓應力係指應力產生包含於玻璃表面層之鹼金屬 離子由具有較大離子半徑之鹼金屬離子化學地增加強度過 12 201029943 程中由於替代產生之應力。在一項實施例中，卸離子替代 在此所說明玻璃表面層中鈉離子。玻璃具有表面壓應力至 少大約200MPa。在一項實施例中，表面壓應力至少大約6〇〇 MPa。在更進一步實施例中，表面壓應力強度至少為 - 。鹼金屬鋁矽酸鹽玻璃具有壓應力層，其具有深度為至少 40微米。 在玻璃網狀結構能夠鬆弛溫度下較小離子由較大離子 0 替代能夠產生離子分佈於玻璃表面，其導致應力分佈。進 入離子較大體積在表面產生壓應力（cs)以及在玻璃中央 (CT)產生張應力。壓應力與中央張力關係如下： CS= CT X (t-2D0L)/D0L，其中t為玻璃厚度以及DOL為交換 深度。 舉例說明本發明，如上面所說明之玻璃組成份可融合 抽拉成為玻璃片為融合抽拉為片狀物試樣"c"以及評估非 本公司商業化玻璃以及標示為試樣"χ","γ",以及"z"。所 Φ 有四樣試樣作離子交換，將K離子替代Na離子。所有玻璃試 樣厚度為1mm。所有玻璃試樣離子交換為最佳化。表I顯示 出四個試樣之離子交換深度。 表1 ----------- X Y Ζ C D〇L( μηι) 15 14 12 63 CS (MPa) 532 500 768 708 溫度，。C 390 430 410 410 時間（Hr) 12 7 11 12 表1顯示出使用在此所說明玻璃，一項能夠達成化學地 13 201029943 增加強度玻璃，其具有層深度D0L(K離子對Na離子離子交換 )大於40微米以及表面壓應力CS為大於700MPa。 如上述所說明，所有玻璃試樣在離子交換處理過程中 作最佳化。因而，試樣代表在圖4-7所顯示玻璃損壞抵抗性 . 之最佳可利用試樣。通常，在最後修飾後包含於離子交換 • 層内之裂縫為較佳的，如同離子交換後強度增加所示。 在圖4-7中X，Y，Z及Z每一交換離子及非交換離子試樣 φ 均進行評估。非離子交換試樣全部加以研磨至相同的5〇 MPa強度值以及作離子交換。圖4顯示出所有試樣在離子交 換之前具有相同的強度，試樣C大約為i〇〇Mpa比研磨後試樣 X，Y以及Z強固。 圖5顯示出限制裂縫開始形成之強度如利用Vickers壓 痕法量測，所有四種試樣均以相同的方式進行。試樣X，γ 以及z所有呈現出徑向裂縫臨界負載在8〇〇1〇〇〇g範圍内。 試樣c並不會呈現出徑向裂縫持續到臨界負載為大於6〇〇〇g 碜 。試樣c之臨界負載至少大於其他試樣負載6倍。The maximum tensile stress limit of a glass object of 500 to 1000 μm is shown in Fig. 2 and each thickness is plotted when CT (+ central stress) is 54 MPa. The W data points in Figure 12 represent chemically increasing the intensity according to the present invention.) D0L/CS relationship. + The cs/D〇L value to the left of the data point can be diluted by the ion exchange bath. If the 60 micron D0L is required, for the 〇. 5, 〇. 7 and 〇. 9 objects, the maximum compressive stress developed on the surface of the glass article can be 52 〇 and 700 MPa, respectively. If specific impact resistance is required, it is generally necessary to specify the layer depth index while limiting the surface compressive stress. The impact record is related to the layer depth, as shown in Figure 13. Figure 13 shows the results obtained by increasing the strength of soda lime glass using the current commercialization, and the symbol_c represents the result obtained by chemically increasing the strength according to the present invention. The combined effect is to be able to control the thin glass to chemically increase the strength parameters to get the required damage resistance. From the point of view of friability, we found that the tensile stress value of the thickness of the glass at about 1 mm should be lower than 54 MPa as calculated using the FSM-6000 surface stress meter measurement CS and D0L. The MPa value will change with the thickness of the glass, which is reduced by the glass change 201029943, the increase in the value of the thin MPa and the thickening of the glass. As the data presented herein shows, the chemically toughened (拎) glass of the present invention has some improvement and characteristics required for height. This θ includes ^ 1. The surface fragmentation caused by sharp objects on the projection glass surface is more resistant, and is higher than other glasses currently used in these devices. _ 2· The resistance to the initial crack is more resistant, and the crack proves to exist in the existing device with coverage. φ 3. Machining and processing cracks caused by ion exchange are encapsulated by the exchange layer and under pressure. This will make the final glass product more tolerant of the finishing process. The present invention makes it possible to utilize a glass component capable of chemically increasing strength (which contains an element capable of ion exchange in glass). Particularly suitable for the glass of the present invention are alkali metal-containing aluminosilicate glasses, alkali metal-containing borosilicate glasses, alkali metal-containing aluminoborosilicate glasses, and alkali metal-containing glass ceramics. In the preferred embodiment ten glass and glass ceramics are transparent. The glass can be chemically increased in strength by ion exchange and the composition can be drawn down into a glass piece. The glass has a melting temperature of less than about 1650 ° C and a liquidus viscosity coefficient of at least 130 kbo and, in one embodiment, greater than 250 kpo. The glass is capable of ion exchange at relatively low temperatures and a depth of at least 3 microns. An exemplary glass has a composition before ion exchange expressed as a percentage of moles: 64% SSi〇2$68%; 12% SNa2〇S16%; 8% SAl2〇3 S12%; 0% SB2〇3^3% 2%SK2〇S5%; 4%SlfeOS6%; and 〇% S CaO S 5%; wherein: 66% S Si〇2+B2〇3+CaO S 69%; Na2〇+K2〇+ 201029943 B2〇3 +MgO+CaO+SrO>l〇°/0;5°/〇^MgO+CaO+Sr0^8°/〇; (Na2〇+ B2〇3) - A12〇3 S 2%; 2% $ Na2〇 S A12 〇 3 S 6%; and 4% S (Na2 〇 + K2 〇) SAl2 〇 d0o / o. Other exemplary glasses have a composition by weight percent before ion exchange: 64-68% Si〇2, 10-12% Ah〇3, 0-2% BA, 12 -15% NazO, 2-4°/ 〇K2〇, 5-7% MgO, >0-1% CaO, 〇-〇. 5°/〇(As2〇3, Sn〇2), 〇-l%(Sb2〇3, SnOO, and > 0-l% Ti〇2. Arsenic and bismuth φ are often added to the glass component as a fining agent to assist in the removal of gaseous impurities in the glass. However, arsenic and recording are generally considered hazardous materials. Thus, in one embodiment The glass is substantially free of recordings and gods, containing less than about 0.05% by weight, beneficially using non-toxic ingredients such as tin, halides, or sulfates to produce a clarifying effect. Tin (IV) oxide (Sn〇2) and tin ( IV) The combination of oxide and toothing is particularly useful as a clarifying agent and can be used in place of the previous components. The glass composition used to make the chemically toughened glass of the present invention can be used as appropriate. Such as fusion pull, slit drawing, rolling sheet, precision pressing and other methods well known in the industry. The preferred method is downward drawing Methods such as fusion draw and slit drawing because they produce glass with a rather original surface. These down draw methods are used for large scale fabrication of ion exchangeable flat glass. The fusion draw process uses a draw cylinder that has a groove The groove receives the molten glass material. The groove has an open top and is located on both sides of the groove along the length of the groove. When the groove is filled with the molten material, the molten glass overflows through the body. Due to gravity, the molten glass flows downward. The outer surface of the barrel is drawn. These outer sides of the 201029943 surface are extended downwardly and upwardly so that they join at the lower edge of the barrel. The two flow (four) surfaces are joined at this edge to fuse and form a single flow glass piece. Providing some advantages, since the two glass films flow through the grooves, the outer surface of the formed glass sheets does not contact any part of the device. Therefore, the surface impurities are not affected by the _ contact. Different from the fusion drawing method, the raw raw glass is provided to the drawing cylinder. The bottom of the drawing tube has an open slit of the nozzle, and the L extension The length of the slit is too long. The molten glass flows through the slit/mouth and pulls down to become a continuous glass sheet and enters the annealing zone. Compared with the fusion drawing process, the slitting process provides a thinner glass sheet. Since only the single-glass piece is pulled down through the slit, instead of the two pieces being melted together, as in the downward fusion-drawing process. In order to match the downward drawing process, the metal is tested here. The silicate glass indicates a high liquidus viscosity coefficient. In one embodiment, the liquid®-phase line viscosity coefficient is at least 130 kilopoise, and in another embodiment, the liquidus viscosity coefficient At least 25 thousand kilopods. In the case of the example, the glass increases the strength by ion exchange. As used herein, 'the so-called "ion exchange" means that the glass is increased in strength by the ion exchange treatment process that is well known in the glass manufacturing industry. The ion exchange treatment process is not limited to the treatment of the age of heating. Or other suitable fields of metal glass) and a heated solution containing ions, the ions have a larger ion half larger than that present in the glass towel, and the purpose is to replace smaller ions with larger ions. For example, potassium ions can replace sodium in glass. Or lithium ion. It can be changed in 201029943. Other metal ions with larger atomic radius, such as ruthenium (Rb) or absolute (Cs), can replace the glass. The metal ions include potassium. Similarly, the other metal salts For example, non-limiting sulfates can be used for ion treatment of contact lenses. When the fine components are used here - and the 100% potassium nitrate bath is used, the ion exchange time and temperature are usually 380-460 C, respectively. And 3-16 hours. The exact time and temperature required depends on the exact glass composition to be ion exchanged. In one embodiment, the glass is laid down by _ The intensity is chemically increased in a bath containing KN〇3 molten salt for a predetermined period of time to achieve ion exchange. In one embodiment, the temperature of the molten salt is about 43 (rCW and a predetermined time of about 8 hours). In another embodiment, ion exchange is first performed using K ions to achieve the desired parental depth and reuse ce or this ion to further enhance the surface by ion exchange with K relatively close to the surface. The drawing process produces a fairly pure surface, since the strength of the glass surface is controlled by the number and size of surface cracks. Φ The initial clean surface with minimal contact has a higher initial strength. When the high strength glass is chemically increased again The strength, the final strength is higher than the surface overlap and the polished surface portion. Increasing the strength or tempering by ion exchange chemistry also increases the resistance of the glass to crack formation due to processing. Thus, in one embodiment, 'for the ugly 300 X400mm glass piece, the downward drawing of the alkali metal aluminosilicate glass warp is less than about 〇. 5 faces. In another embodiment The warpage is less than about 0.3 m. The surface compressive stress refers to the stress generated by the alkali metal ions contained in the surface layer of the glass. The chemical strength of the alkali metal ions having a larger ionic radius is chemically increased over 12 201029943. In one embodiment, the ion is removed to replace the sodium ion in the glass surface layer described herein. The glass has a surface compressive stress of at least about 200 MPa. In one embodiment, the surface compressive stress is at least about 6 MPa. In a further embodiment, the surface compressive stress strength is at least - the alkali metal aluminosilicate glass has a compressive stress layer having a depth of at least 40 microns. The smaller ions are larger ions at a relaxation temperature of the glass network structure. The alternative is capable of generating ions distributed on the glass surface which results in a stress distribution. The larger volume of incoming ions creates compressive stress (cs) on the surface and tensile stress in the center of the glass (CT). The relationship between compressive stress and central tension is as follows: CS = CT X (t-2D0L) / D0L, where t is the thickness of the glass and DOL is the exchange depth. By way of example, the glass composition of the invention can be fused and expanded into a glass sheet for fusion drawing into a sheet sample "c" and evaluation of non-commercialized glass of the company and labeling as a sample "χ";,"γ", and "z". There are four samples for ion exchange, and K ions are substituted for Na ions. All glass samples have a thickness of 1 mm. All glass samples were ion exchange optimized. Table I shows the ion exchange depth of the four samples. Table 1 ----------- X Y Ζ C D〇L ( μηι) 15 14 12 63 CS (MPa) 532 500 768 708 Temperature,. C 390 430 410 410 Time (Hr) 12 7 11 12 Table 1 shows the use of the glass described here, one capable of achieving chemically 13 201029943 increased strength glass with layer depth D0L (K ion to Na ion ion exchange) Greater than 40 microns and surface compressive stress CS greater than 700 MPa. As explained above, all glass samples were optimized during the ion exchange process. Thus, the sample represents the best available sample for the glass damage resistance shown in Figures 4-7. Generally, the cracks contained in the ion exchange layer after the final modification are preferred as shown by the increase in strength after ion exchange. In Figure 4-7, each of the exchanged ions and non-exchanged ion samples φ of X, Y, Z and Z were evaluated. The non-ion exchanged samples were all ground to the same 5 MPa MPa strength value and ion exchanged. Figure 4 shows that all samples have the same strength before ion exchange, and sample C is approximately i〇〇Mpa stronger than the samples X, Y and Z after grinding. Figure 5 shows the strength at which the crack initiation begins to be formed as measured by the Vickers indentation method, and all four samples were carried out in the same manner. Samples X, γ and z all exhibited a radial crack critical load in the range of 8〇〇1〇〇〇g. Sample c does not exhibit radial cracking until the critical load is greater than 6 〇〇〇g 碜 . The critical load of sample c is at least 6 times greater than the load of other samples.
圖6顯不出在依據astm方法C158利用尖銳堅硬SiC顆粒 喷砂處理後離子交換試樣X，γ，z以及c之強度。x—轴，標示π 接觸力量係數"或，W為·尺寸以及噴砂處理壓力之組 合。喷妙處理之SiC顆粒磨韻玻璃表面。在训喷砂處理後 玻璃強度使用ting-〇n環方法進行量測。顯示於圖6中結果 顯示所有試樣X，Y錢Z具有初始強度（單位為_在棚以 及5500之間，其中試樣c具有初始強度約為奶胸。在CFF 、約為10下SiC喷砂處理後，所有試樣X，Y以及X顯示強度在80 201029943 -lOOMPa範圍内，其中試樣c顯示出平均強度约為4〇〇MPa。 圖7顯示出所需要初始形成側向裂縫之負載為剝離的 原因。侧向裂縫門檻值（可見缺陷）使用Vickers壓痕器量 測。[ASTM法並無Vickers壓痕器測試，該方法說明於Tandon 等人之 Stress Effects in Indentation Fracture Sequences, J. Am. Ceram Soc. 73 [9] 2619-2627 (1990); R. Tandon 等人之 Indentation Behavior of I〇n-Exchanges Glasses" φ J· Am_ Ceram Soc. 73 [4] 970-077 (1990);以及 P.H.Figure 6 shows the intensity of the ion exchange samples X, γ, z and c after blasting with sharp hard SiC particles according to the ast method C158. The x-axis indicates the π contact force coefficient " or, W is the combination of size and blasting pressure. The SiC particles are polished to the surface of the glass. After the sand blasting treatment, the glass strength was measured using the ting-〇n ring method. The results shown in Figure 6 show that all samples X, Y Qian Z have an initial strength (unit is between shed and 5500, where sample c has an initial strength of about milk breast. At CFF, about 10 SiC spray After sand treatment, all samples X, Y and X showed an intensity in the range of 80 201029943 -100 MPa, wherein sample c showed an average strength of about 4 MPa. Figure 7 shows that the initial load required to form a lateral crack is Reasons for peeling. Lateral crack threshold values (visible defects) were measured using a Vickers indenter. [The ASTM method does not have a Vickers indenter test, which is described in Tandon et al.'s Stress Effects in Indentation Fracture Sequences, J. Am. Ceram Soc. 73 [9] 2619-2627 (1990); R. Tandon et al., Indentation Behavior of I〇n-Exchanges Glasses" φ J· Am_ Ceram Soc. 73 [4] 970-077 (1990); PH
Kobrin 等人之’The Effects of Thin Compressive Films on Indentation Fracture Toughness Measurements," J. Mater. Sci. 24 [4] 1363-1367 (1980)]。上述每一 長條數目代表每一試樣離子交換層之深度以及亦顯示於表 1中。顯示於圖7中之結果顯示出試樣χ，γ&Ζ裂縫初始形成 所需要臨界負載大約在800 _ 1400g範圍内，其中試樣c並無 橫向裂縫，以及因而並未形成碎片，觀察到負載高達6〇〇〇g 參 。結果顯示出試樣C側向裂縫抵抗性超過試樣X，γ以及z至 少4倍。 圖8以及9顯示出本發明玻璃損壞抵抗性改善優於商業 可利用使用作為保護性覆蓋之玻璃。使用UMT刮痕測試法 進行測試。UTM為商業化儀器（CETR Inc.，Campbell，CA) ’其允許允許各種型式之摩擦性測試，包括刮痕測試。適當 的參考文獻為 V.Le Houerou 等人之"Surface Damage of Soda lime silica Glasses: Indentation Scratch Behavior," J. Non Cryst Solids, 316 [1] 54-63 (2003)。在該測 15 201029943Kobrin et al. 'The Effects of Thin Compressive Films on Indentation Fracture Toughness Measurements," J. Mater. Sci. 24 [4] 1363-1367 (1980)]. The number of each of the above bars represents the depth of the ion exchange layer of each sample and is also shown in Table 1. The results shown in Figure 7 show that the critical load required for the initial formation of the χ, γ & Ζ crack is approximately 800 _ 1400 g, where the sample c has no transverse cracks and thus no debris is formed, and the load is observed. Up to 6〇〇〇g ginseng. The results showed that the lateral crack resistance of the sample C was at least 4 times higher than that of the samples X, γ and z. Figures 8 and 9 show that the glass damage resistance improvement of the present invention is superior to that of commercially available glass as a protective cover. The test was performed using the UMT scratch test method. UTM is a commercial instrument (CETR Inc., Campbell, CA) that allows for various types of friction testing, including scratch testing. A suitable reference is V. Le Houerou et al. "Surface Damage of Soda lime silica Glasses: Indentation Scratch Behavior," J. Non Cryst Solids, 316 [1] 54-63 (2003). In the test 15 201029943
試中Knoop壓痕器拉引通過表面並在大約1〇〇秒内增加壓痕 負載至500公克最大負載（以區分玻璃與玻璃之差異）。F 圖8以及9顯示出藉由在增加負載下滑移KnQ〇p鑽石壓 痕器分別地經由玻璃試樣γ以及C之表面所弓丨起顺。數值 30以及40代表每一試樣開始以及最終刮痕測試點。對於兩 者試樣Y以及C，玻璃存在由壓痕器溝槽所形成溝槽以及剝 離如所預期情況。不過，在試樣γ中為三階段損壞，其為刮 參痕溝槽，側向裂縫(數目5〇,線條A以及B)以及碎裂(數目6〇, 線條A以及B)。試樣γ之侧向裂縫以及碎裂發生於小於· 公克負載下。亦產生中間裂縫出口。在試#c中並未顯現 側向裂縫或碎裂，其只顯示出到痕溝槽。在本發明中玻璃 物品在該測試中高達500公克並未形成該裂縫系統。圖ι〇 為圖8中試樣γ箭頭·所標示之放大圖以及顯示出碎裂盆 發生於試樣該點處。類似碎裂能夠發現於該區域試樣γ中 以箭頭60Β表示以及沿著溝槽各處。圖u為圖8中試樣γ區 ❷域箭頭5〇Α表示之放大圖以及顯示出側向裂縫形成於試樣 Υ中° _側向㈣能夠試樣γ中沿著溝槽線各處。 不像已使用來製造覆蓋玻璃之浮式玻璃，融合形成以 及細縫抽拉玻璃在修飾過程中並不必需變薄。一旦邊緣加 以處理，玻璃立即可作為產品組件。此將降低製造覆蓋玻 璃之4貝格，特別作為需要大玻璃表面積之裝置例如腿觸摸 銀幕’筆記型電腦以及其他大的銀幕裝置。有利於表面形 成亦會影響採用之製造處理步驟。生產裝置投資以及處理 過程時間能夠有助於邊緣研磨操作，其因而能夠允許更嚴 16 201029943 雄、處理過程之控制以及因而改善研磨邊緣之強度，該區域 通常是最先破壞區域。 雖然所揭示實施例作為列舉用途，先前說明並不視為 對本發明$111作限制。因而業界熟知此技術者受益於所 揭示内容能夠設計出各種變化，改變以及替代而並不會脫 離在此所揭示本發明之内容。 【圖式簡單說明】The Knoop indenter was pulled through the surface and increased the indentation load to a maximum load of 500 grams (to differentiate between glass and glass) in approximately 1 second. F Figures 8 and 9 show the smoothing of the KnQ〇p diamond indenter via the glass samples γ and C, respectively, by increasing the load. Values 30 and 40 represent the start of each sample and the final scratch test point. For both samples Y and C, the glass had grooves formed by the indenter grooves and peeling as expected. However, there was a three-stage damage in the sample γ, which was a scratched groove, a lateral crack (number 5 〇, lines A and B), and a chipping (number 6 〇, lines A and B). The lateral cracks and fractures of the sample γ occur under a load of less than gram. Intermediate crack outlets are also produced. No lateral cracks or chippings were observed in test #c, which only showed trace grooves. In the present invention, the glass article did not form the crack system up to 500 grams in this test. Figure ι〇 is an enlarged view of the sample γ arrow in Figure 8 and shows that the fragmentation basin occurs at the point of the sample. Similar fragmentation can be found in the sample γ in this region as indicated by arrow 60Β and along the trench. Figure u is an enlarged view of the γ-region of the sample in Figure 8 and indicated by the arrow 5〇Α and shows that the lateral crack is formed in the sample °. _ Lateral (4) The sample γ can be located along the groove line. Unlike the floating glass that has been used to make cover glass, the fusion formation and the slit drawn glass do not have to be thinned during the modification process. Once the edge is processed, the glass is immediately available as a product component. This will reduce the production of 4 Å of cover glass, especially as a device that requires a large glass surface area such as a leg-touch screen computer and other large screen devices. Facilitating the formation of the surface also affects the manufacturing process steps employed. Production plant investment and process time can contribute to the edge grinding operation, which can thus allow for more stringent control of the process, and thus the strength of the abrasive edge, which is typically the first damage zone. Although the disclosed embodiments are used as an enumerated use, the foregoing description is not to be construed as limiting the invention. Thus, those skilled in the art will be able to devise various modifications, changes and substitutions without departing from the scope of the invention disclosed herein. [Simple description of the map]
圖1顯示出商業使用玻璃材料以及由於使用到痕存在 於表面上。 圖2顯示出商業使用玻璃材料以及由於玻璃接觸尖銳 或受物體衝擊造成的損壞。 圖3示意性地顯示出具有深度D〇L，表面壓應力&以及 中央張力CT之離子交換層的玻璃。 圖4為曲線圖，其顯示出在離子交換之前及之後經選 擇玻璃材料的強度。 圖5為曲線圖，其顯示出當利用Vickers壓痕法量測時 限制徑向裂縫啟始強度。 “ 圖6為曲線圖，其顯示出在使用SiC顆粒作空 研磨後經選擇離子交換玻璃之強度。 ”^ 圖7為曲線圖，其顯示出使用Vickers壓痕量測側向裂 縫最初門播值（目視缺陷）。 —圖8顯不出藉由滑移Knoop鑽石壓痕器經過商業可利用 覆蓋玻璃彳丨起刮痕損傷。 圖9顯示域由滑移K_p伽壓痕過依據本發明 201029943 化學地增加強度覆蓋_狀舰鑛。 圖10為箭頭60A所顯示區域之放大圖以及顯示出在商 業化玻璃中發生的剝離。 圖11為箭頭50A所顯示區域之放大圖以及顯示出在商 業化玻璃中發生的側向裂縫。 圖12為曲線圖，其顯示出不同厚度玻璃（一般）以及本 發明玻璃D0L以及CS間之關係。 圖13為曲線圖，其顯示出目前使用作為保護性玻續之 化學地增加強度蘇打石灰玻璃以及本發明玻璃之臨界負栽 與層深度(D0L)關係。 【主要元件符號說明】 無0 ❹ 18Figure 1 shows the commercial use of glass materials and the presence of traces on the surface. Figure 2 shows the commercial use of glass materials and damage due to sharp contact of the glass or impact by objects. Fig. 3 schematically shows a glass having an ion exchange layer of depth D 〇 L, surface compressive stress & and central tension CT. Figure 4 is a graph showing the strength of the selected glass material before and after ion exchange. Fig. 5 is a graph showing the limitation of the radial crack initiation strength when measured by the Vickers indentation method. Figure 6 is a graph showing the strength of selected ion exchange glass after SiC particles are used for air milling. "^ Figure 7 is a graph showing the initial gated value of the lateral crack using the Vickers indentation measurement. (visual defects). - Figure 8 shows that scratch-resistant damage can be achieved by slipping the Knoop diamond indenter through commercially available cover glass. Figure 9 shows the field by slip K_p gamma indentation according to the invention 201029943 chemically increasing the intensity coverage of the _ sine mine. Figure 10 is an enlarged view of the area indicated by arrow 60A and showing the peeling that occurs in the commercial glass. Figure 11 is an enlarged view of the area indicated by arrow 50A and showing the lateral cracks occurring in the commercial glass. Fig. 12 is a graph showing the relationship between glass of different thicknesses (generally) and the glass of the present invention D0L and CS. Fig. 13 is a graph showing the relationship between the critical load and the layer depth (D0L) of the chemically increased strength soda lime glass currently used as a protective glass and the glass of the present invention. [Main component symbol description] No 0 ❹ 18