TWI377181B

TWI377181B -

Info

Publication number: TWI377181B
Application number: TW097139757A
Authority: TW
Inventors: Yuichi Kuroki; Mineko Yamamoto; Yasuo Hayashi; Hideki Kushitani; Syuji Matsumoto; Terutaka Maehara; Junichiro Kase
Original assignee: Asahi Glass Co Ltd
Priority date: 2007-10-25
Filing date: 2008-10-16
Publication date: 2012-11-21
Also published as: JP5267464B2; KR20100085900A; KR101489983B1; WO2009054314A1; TW200927686A; CN101808951B; CN101808951A; JPWO2009054314A1

Description

1377181 九、發明說明【發明所屬之技術領域】本發明係關於無鹼玻璃之製造方法。 4 ' 【先前技術】於液晶顯示基板用玻璃中，由於被要求著實質上不含有鹼金屬’則作爲該玻璃，無鹼玻璃被使用著。又，對於 φ 液晶顯示基板用之無鹼玻璃，也被要求著高耐藥性、高耐久性、玻璃中之泡爲少、高均質性、高平坦度。因此，爲賦予無鹼玻璃耐藥品性、耐久性，使玻璃原料包含硼源，及爲了減少無鹼玻璃中之泡，於製造無鹼玻璃時將包含於熔融玻璃中之泡進行脫泡（以下，記爲澄清）。尙，作爲硼源，使用便宜且容易取得之正硼酸。作爲澄清方法’周知有使用作爲澄清劑之Sn02，藉由熔融玻璃之昇溫造成之Sn的價數變化，使其產生澄清 φ 氣體之方法（專利文獻1)。但，液晶顯示基板用之無鹼玻璃，與電漿顯示基板用 • 玻璃、建築用玻璃、汽車用玻璃等之含有鹼玻璃相比，其熔融溫度高於100 °c以上，爲不易熔融之玻璃。因此，將玻璃原料在高溫下使其熔融時，Sn02將會被消耗，有由於熔融玻璃之昇溫而發生澄清氣^時，並無殘留足夠量之 Sn02之問題。作爲使用Sn02的有效澄清方法，公知有將玻璃原料在高溫下熔融後，在低溫下保持將Sn02重製，其後，使 -5- 1377181 其昇溫至比前述熔融溫度還高，而使澄清氣體 (專利文獻2 )。該方法之場合，雖可期待有效的澄清，但又因其能量損耗大，在低成本下難以安定製造 ‘ 玻璃。另一方面，若打算在低溫下將玻璃原料爲玻璃原料主成分之矽砂不易熔融，有在熔融未融二氧化矽之缺點，有時會無法取得均質之 φ 又，爲了使矽砂容易熔融，使用粒徑爲小合時，則矽砂容易聚集。若矽砂聚集產生，無質性、平坦度將會降低。〔專利文獻1〕特開2004-075498號公報〔專利文獻2〕國際公開第2007/018910 ¾ 【發明內容】〔發明所欲解決之課題〕 Φ 本發明提供一種可取得玻璃中之泡爲少，平坦度爲高之無鹼玻璃之製造方法。〔用以解決課題之手段〕本發明之無鹼玻璃之製造方法，其係對含源之玻璃母材組成原料中添加了澄清劑之玻璃融而成型之無鹼玻璃之製造方法，其特徵爲，砂，使用中徑爲1 5~60μιη且粒徑〗〇〇μιη以上例爲2.5體積％以下者，作爲上述硼源，相對於產生之方法· 步驟複雜，少泡之無鹼熔融，因作玻璃內發生玻璃。之矽砂的場鹼玻璃之均 I手冊且均質性、有砂砂及硼原料進行熔作爲上述矽之粒子之比 -1 0 0質量％ 1377181 (以B2〇3換算）之砸源，使用含有10〜100質量％之硼酸. 酐（以B2〇3換算）者，作爲上述澄清劑，至少使用Sn02 ’至少以下述之2步驟進行上述玻璃原料之熔融： (a) 將上述玻璃原料以使熔融玻璃之黏度超過 l〇24dPa· s之溫度加熱，製成熔融玻璃之步驟； (b) 上述步驟（a)後，將上述熔融玻璃以使熔融玻璃之黏度爲1 0 2 4dPa · s以下且比上述步驟（a)中之溫度高3 (TC以上之溫度加熱，使熔融玻璃中之泡脫泡之步驟。本發明之無鹼玻璃之製造方法中，在前述玻璃母材組成原料中，以含有鋁或鹼土類金屬之氫氧化物爲佳。本發明之無鹼玻璃之製造方法中，以氧化物爲基準之質量百分比之表示下，將玻璃母材組成原料調製成如下述玻璃母材組成（1 )之無鹼玻璃，相對於該玻璃母材組成材料添加錫以Sn02換算之〇.〇1~2質量％使成玻璃原料爲佳。1377181 IX. Description of the Invention [Technical Field of the Invention] The present invention relates to a method for producing an alkali-free glass. 4' [Prior Art] In the glass for a liquid crystal display substrate, since it is required to contain substantially no alkali metal, the glass is used as the glass, and the alkali-free glass is used. Further, the alkali-free glass for the φ liquid crystal display substrate is required to have high chemical resistance, high durability, low bubbles in the glass, high homogeneity, and high flatness. Therefore, in order to impart chemical resistance and durability to the alkali-free glass, the glass raw material contains a boron source, and in order to reduce bubbles in the alkali-free glass, the bubbles contained in the molten glass are defoamed in the production of the alkali-free glass (hereinafter, , remember as clarification). Helium, as a source of boron, uses ortho-boric acid which is inexpensive and easily available. As a clarification method, a method of using a Sn02 as a clarifying agent to change the valence of Sn by the temperature rise of the molten glass to produce a clarified φ gas is known (Patent Document 1). However, the alkali-free glass for a liquid crystal display substrate has a melting temperature higher than 100 ° C or higher than that of an alkali glass containing a glass for a plasma display substrate, glass for construction, or glass for automobiles, and is a glass that is not easily melted. . Therefore, when the glass raw material is melted at a high temperature, Sn02 is consumed, and when the clarified gas is generated due to the temperature rise of the molten glass, there is no problem that a sufficient amount of SnO remains. As an effective clarification method using Sn02, it is known that after the glass raw material is melted at a high temperature, the Sn02 is kept at a low temperature, and thereafter, the temperature is increased to -1377181, which is higher than the melting temperature, and the clarified gas is made. (Patent Document 2). In the case of this method, although effective clarification can be expected, it is difficult to stably manufacture "glass" at a low cost because of its large energy loss. On the other hand, if it is intended to melt the glass raw material as the main component of the glass raw material at a low temperature, it is difficult to melt the unmelted cerium oxide, and it is sometimes impossible to obtain a homogeneous φ. When the particle size is small, the sand is easy to aggregate. If the sand is aggregated, the purity and flatness will decrease. [Patent Document 1] JP-A-2004-075498 (Patent Document 2) International Publication No. 2007/018910 3⁄4 [Summary of the Invention] [Problems to be Solved by the Invention] Φ The present invention provides a bubble which can be obtained in a glass. A method for producing an alkali-free glass having a high degree of flatness. [Means for Solving the Problem] The method for producing an alkali-free glass according to the present invention is a method for producing an alkali-free glass in which a glass containing a clarifying agent is added to a raw material of a glass base material containing a source, and is characterized in that , sand, using a median diameter of 1 5~60μιη and a particle size of 〇〇μιη or more in the case of 2.5% by volume or less. As the above-mentioned boron source, the method and the steps are complicated, and the alkali-free melting of the foam is caused by Glass occurs inside the glass. The amount of the field alkali glass of the 矽矽 I 手册手册手册手册手册手册手册手册手册手册手册手册手册手册手册手册手册手册手册手册 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 10 to 100% by mass of boric acid. An anhydride (calculated as B2〇3), as the clarifying agent, at least Sn02' is used to melt the glass raw material at least in the following two steps: (a) melting the glass raw material described above The glass is heated at a temperature exceeding l〇24 dPa·s to form a molten glass; (b) after the above step (a), the molten glass is made so that the viscosity of the molten glass is 1 0 2 4 dPa·s or less and The step (a) in which the temperature is higher than 3 (the temperature of TC or higher is heated to defoam the bubbles in the molten glass. In the method for producing an alkali-free glass according to the present invention, the glass base material is contained in the raw material. The aluminum or alkaline earth metal hydroxide is preferred. In the method for producing an alkali-free glass according to the present invention, the glass base material composition is prepared to have a glass base material composition as indicated by the mass percentage based on the oxide ( 1) no Glass, a glass base material with respect to the material composition in terms of the addition of tin to Sn02 〇.〇1 ~ 2 mass% to the glass material is so good.

Si〇2 : 50~66 質量％、AI2O3 : 1〇·5~22 質量％、B2O3 : 5〜12 質量％、MgO : 0〜8 質量％、CaO : 0~14.5 質量％、 SrO: 〇〜24 質量％、BaO: 0-13.5 質量％、MgO + CaO + SrO + BaO : 9〜29.5 質量％ . . · ( 1 )。本發明之無鹼玻璃之製造方法中’以相對於上述玻璃母材組成原料，更進一步，添加從以C1換算之3質量％以下之氯化物，以S03換算之3質量％以下之硫酸鹽及以F 換算之3質量％以下之氟化物所構成之群中選出一種以上之合計量爲0·0 1~5質量％而作.爲玻璃原料爲佳。 1377181 本發明之無鹼玻璃之製造方法中，以相對於上述玻璃母材組成原料’更進一步’添加以N〇3換算之〇.〇1〜1〇質量％之硝酸鹽及無鹼玻璃所構成之玻璃屑15〜300質量％而作爲玻璃原料爲佳。〔發明之效果〕依據本發明之無鹼玻璃之製造方法，可取得玻璃中之 φ 泡爲少，均質性、平坦度爲高之無鹼玻璃。【實施方式】〔實施發明之最佳形態〕 <無鹼玻璃之製造方法> 無鹼玻璃的製造係藉由對含有矽砂及硼源之玻璃母材組成原料中添加了澄清劑之玻璃原料進行熔融而成型。無鹼玻璃係例如經由下述順序之步驟而製造。 0 (i)將矽砂及硼源，或依據需要Al2〇3、鹼土類金屬氧化物（MgO、CaO、SrO、BaO)及/或鋁或鹼土類金屬 . 之氫氧化物以使成爲目標之無鹼玻璃之玻璃母材組成之比例混合調製成玻璃母材組成原料，於該玻璃母材組成原料之窯融熔從屑璃。玻驟之步要之需料據原依璃及玻料爲原成璃使玻 ^ 0 劑將清} 澄：11 加C 添中融熔爲成而融熔其使內窯融熔入投續 imu 連 □ 入。投驟料步原之璃璃玻玻使法型成的知公. 之等法式浮由藉璃玻融熔該將 -8 - 1377181 其成爲指定厚度的玻璃帶之成型步驟。 (iv)使成型後之玻璃帶緩冷卻後、將其切斷爲指定之尺寸，而得到板狀之無鹼玻璃的步驟。本發明其特徵爲，作爲前述矽砂，使用中徑爲15〜 60μιη，且粒徑ΙΟΟμιη以上之粒子的比例爲2.5體積％以下者’作爲前述硼源，使用硼源100質量％ (以Β2〇3換算）之中，含有ίο〜1〇〇質量％ (以β2〇3換算）之硼酸酐者， φ 作爲前述澄清劑，至少使用Sn〇2 ’將前述步驟（η)分爲至少下述2步驟進行。 (a) 將前述玻璃原料在熔融玻璃之黏度成爲超過 102 4dPa· s之溫度下加熱’使成爲熔融玻璃之步驟。 (b) 前述步驟（a)之後，將前述熔融玻璃，在熔融玻璃之黏度成爲1024dPa. s以下之溫度下且比前述步驟 (a)中之溫度局30C以上之溫度下加熱，使溶融玻璃中之泡進行脫泡之步驟。步驟（i ): . (矽砂）矽砂之中徑’即粉體之粒度分佈，比某粒徑大之粒子的體積頻度爲佔有全粉體之體積頻度的50%之粒子徑（以下’記爲D5〇)，爲15〜60μιη，以20〜50μπι爲佳，20〜 40μηι爲較佳、20〜30μπι爲更佳。矽砂之d5〇特別係以未滿30μιη爲佳，更進一步以27μιη以下爲佳。藉由使矽砂之D s 〇爲1 5 μ m以上，因矽砂之聚集可被抑制，可得到泡 -9- 1377181 爲更少，且均質性、平坦度爲高之無鹼玻璃。藉由使砂砂之Dsg爲60μιη以下，因砂砂可容易均句地熔融，可得到泡爲少’且均質性、平坦度爲高之無驗玻璃》 ' 砂砂之粒度分佈中粒徑ΙΟΟμιη以上之粒子之比例爲 2.5體積％以下’以0體積％爲更佳。藉由使粒徑1〇〇μηι以上之粒子的比例在2 · 5體積％以下，因矽砂可容易均勻地 φ 熔融，可得到泡爲少’且均質性 '平坦度爲高之無驗玻璃〇矽砂之粒度分佈可藉由雷射衍射.散射法測定。 (硼源）作爲硼源之硼化合物，可舉出正硼酸（η3βο3 )、偏硼酸（ηβο2 )、四硼酸（Η2Β407 )、硼酸酐（β2〇3 )等。在通常之無鹼玻璃之製造中，以便宜且容易取得之觀點 Φ ，使用著正硼酸。但，使用含有正硼酸之玻璃原料之場合時，會有發生 _ 以下等問題的情況。 (1) 於正硼酸的存在下中，粒徑爲小之矽砂容易聚集’對投入熔融窯之玻璃原料的投入量則容易變爲不安定。因此，熔融窯內之熔融玻璃的溫度會變爲不安定，又，熔融玻璃的循環·滯留時間變爲不安定。其結果，玻璃原料的熔融變的不均勻，又，熔融玻璃的組成變的不均勻。 (2) 玻璃原料爲含有鹼土類金屬化合物之場合時， -10- 1377181 在溶解窯的玻璃原料投入口所熔融之正硼酸，與鹼土類金屬化合物聚集，而容易產生聚集物。因正硼酸及鹼土類金屬化合物因也係爲促進矽砂之熔融之成分，若聚集物產生時，熔融窯內中玻璃原料的熔融會變的不均勻，又，熔融 ' 玻璃的組成也會變的不均勻。若（1)或（2)之問題發生時，因熔融玻璃的均質性變差，則所成型之無鹼玻璃的均質性、平坦度降低。又， φ 因循環•滯留時間變的不安定，泡藉由澄清劑從熔融窯內的熔融玻璃脫出前，熔融玻璃的一部份會從熔融窯流出。又，因玻璃原料的熔融爲不均勻，相對於較慢熔融的矽砂，澄清劑的效果變的不足，泡無法充份地從熔融玻璃中脫出。有關於（1)的問題，本發明者們發現，矽砂的聚集係因爲玻璃原料中含有水分所引起，然後，爲抑制矽砂的聚集，只要將玻璃原料所含的水分減少即可，亦即減少分 Φ 子中含有多量水分子之正硼酸的量，增加硼酸酐之量即可〇 . 又，關於（2)的問題，本發明者們發現，在玻璃原料投入口被加熱後之正硼酸中失去一個水分子而成爲偏硼酸，在150 °C以上被液化之偏硼酸則會與鹼土類金屬化合物聚集，接著，爲抑制偏硼酸與鹼土類金屬化合物之聚集，使用含有身爲從偏硼酸中更失去水分子之狀態之硼酸酐的硼源即可。更進一步’藉由使用含有硼酸酐之硼源，也可期待有 -11 - 1377181 以下之效果。 (i) 由於玻璃原料中之水分量被抑制’將玻璃原料熔融時之水的汽化熱則會減少。因此’在熔融窯中被消耗 ' 之能量因汽化熱減少而減少了汽化熱的部份’而可謀求省 ' 能源化，且提高生產性。 (ii) 因熔融玻璃中之水分（yS -0H )減少’澄清劑中含有C1之場合時，藉由下述反應成爲HC1’而可抑制 φ 揮發。因此，可減低澄清劑之量’更減少含有HC1之排氣處理的負擔。 oir + cr— hci 个 +〇2·。 (iii) 從正硼酸中失去一個水分子而生成之偏硼酸，雖然容易揮發，因硼酸酐不容易揮發，可降低硼源之量，更減少含有偏硼酸之排氣處理的負擔。因此，於本發明中，作爲硼源，使用硼源100質量％ (以B2〇3換算）之中，含有10〜100質量％ (以b2o3換 φ 算）之硼酸酐者。藉由控制硼酸酐在1 0質量％以上，可得到抑制玻璃原料之聚集，減少泡的效果，均質性、平坦度 . 提高之效果。硼酸酐以20〜1〇〇質量％爲較佳，50〜100 質量％爲更佳，1〇〇質量％爲特佳。作爲硼酸酐以外之硼化合物，從便宜及容易取得之觀點看來，以正硼酸爲理想。 (其他原料）作爲其他原料，可舉出Al2〇3、驗土類金屬氧化物（ -12- 1377181Si〇2 : 50 to 66% by mass, AI2O3: 1〇·5 to 22% by mass, B2O3: 5 to 12% by mass, MgO: 0 to 8% by mass, CaO: 0 to 14.5% by mass, SrO: 〇~24 Mass%, BaO: 0-13.5 mass%, MgO + CaO + SrO + BaO: 9 to 29.5 mass% . . . (1). In the method for producing an alkali-free glass of the present invention, the sulphate is added to the raw material of the glass base material, and further, a sulphate of 3% by mass or less in terms of C1 and 3% by mass or less in terms of S03 is added. It is preferable to select one or more of the group consisting of fluorides of 3% by mass or less in terms of F to be 0. 0 to 5% by mass. 1377181 In the method for producing an alkali-free glass according to the present invention, a nitrate and an alkali-free glass in an amount of N〇3 in terms of N〇3 are added to the raw material of the glass base material. The glass cullet is preferably 15 to 300% by mass, and is preferably used as a glass material. [Effects of the Invention] According to the method for producing an alkali-free glass of the present invention, an alkali-free glass having less φ bubbles in the glass and having high homogeneity and flatness can be obtained. [Embodiment] [Best Mode for Carrying Out the Invention] <Production Method of Alkali-Free Glass> The production of an alkali-free glass is a glass in which a clarifying agent is added to a raw material of a glass base material containing a cerium and a boron source. The raw material is melted and molded. The alkali-free glass is produced, for example, by the procedure of the following procedure. 0 (i) A sand source and a boron source, or a hydroxide of Al2〇3, an alkaline earth metal oxide (MgO, CaO, SrO, BaO) and/or an aluminum or alkaline earth metal, as required The ratio of the composition of the glass base material of the alkali-free glass is mixed and prepared into a raw material of the glass base material, and the kiln which is the raw material of the glass base material is melted from the slag. According to the original glass and glass material, the raw material is made of glass. The agent will be clear. 澄:11 Add C Add the melt into the melt and melt it to melt the inner kiln into the cast. Imu is connected. The initial step of the glass glaze is made by the glass of the glass. The float of the method is floated by the glass, and the -8 - 1377181 is formed into a glass ribbon of a specified thickness. (iv) A step of obtaining a plate-shaped alkali-free glass by slowly cooling the formed glass ribbon and cutting it into a specified size. The present invention is characterized in that, as the ceramsite, a medium diameter of 15 to 60 μm is used, and a ratio of particles having a particle diameter of ΙΟΟμη or more is 2.5% by volume or less. 'As the boron source, a boron source is used in an amount of 100% by mass. Among the 3 conversions, the boronic anhydride containing ίο~1〇〇% by mass (calculated as β2〇3), φ as the clarifying agent, at least the above step (η) is divided into at least the following 2 The steps are carried out. (a) A step of heating the glass raw material at a temperature at which the viscosity of the molten glass is more than 102 4 dPa·s to form a molten glass. (b) after the step (a), the molten glass is heated at a temperature of 1024 dPa·s or less at a viscosity of the molten glass and at a temperature of 30 C or more higher than the temperature in the step (a), so that the molten glass is in the molten glass. The bubble is subjected to a step of defoaming. Step (i): . (矽砂) The diameter of the sand is the particle size distribution of the powder. The volume of the particles larger than a certain particle size is the particle diameter of 50% of the volume of the whole powder (below below' It is referred to as D5〇), which is 15 to 60 μm, preferably 20 to 50 μm, and 20 to 40 μm is preferably 20 to 30 μm. The d5 矽 of the 矽 sand is particularly preferably less than 30 μm, and further preferably 27 μm or less. By setting the D s of the strontium to 15 μm or more, the aggregation of the strontium sand can be suppressed, and the alkali-free glass having less -9 - 1377181 and having high homogeneity and flatness can be obtained. By setting the Dsg of the sand to 60 μm or less, the sand can be easily melted uniformly, and the glass having less bubbles and having high homogeneity and flatness can be obtained. The particle size distribution of the sand is ΙΟΟμιη The ratio of the above particles is 2.5% by volume or less 'more preferably 0% by volume. When the ratio of the particles having a particle diameter of 1 〇〇μηι or more is 2·5% by volume or less, the cerium can be easily and uniformly φ-fused, and a non-glass having a small bubble and a high degree of homogeneity can be obtained. The particle size distribution of the strontium sand can be determined by laser diffraction and scattering. (Boron source) Examples of the boron compound as a boron source include orthoboric acid (η3βο3), metaboric acid (ηβο2), tetraboric acid (Η2Β407), and boric anhydride (β2〇3). In the production of a normal alkali-free glass, orthoboric acid is used from the viewpoint of being inexpensive and easily obtained. However, when a glass material containing orthoboric acid is used, problems such as _ may occur. (1) In the presence of orthoboric acid, the amount of cerium that is small in particle size tends to accumulate. The amount of input to the glass raw material that is put into the melting kiln is likely to become unstable. Therefore, the temperature of the molten glass in the melting kiln becomes unstable, and the cycle and residence time of the molten glass becomes unstable. As a result, the melting of the glass raw material becomes uneven, and the composition of the molten glass becomes uneven. (2) When the glass raw material is an alkaline earth metal compound, -10- 1377181 The orthoboric acid melted in the glass raw material input port of the dissolution kiln aggregates with the alkaline earth metal compound, and aggregates are likely to occur. Since the orthoboric acid and the alkaline earth metal compound are also components which promote the melting of the cerium, when the aggregate is generated, the melting of the glass raw material in the melting kiln becomes uneven, and the composition of the molten glass changes. Uneven. When the problem of (1) or (2) occurs, the homogeneity of the molten glass is deteriorated, and the homogeneity and flatness of the formed alkali-free glass are lowered. Further, φ is unstable due to cycle and residence time, and a part of the molten glass flows out of the melting kiln before the bubble is removed from the molten glass in the melting kiln by the clarifying agent. Further, since the melting of the glass raw material is uneven, the effect of the clarifying agent is insufficient with respect to the slow-melting cerium sand, and the bubbles cannot be sufficiently removed from the molten glass. Regarding the problem of (1), the inventors have found that the aggregation of cerium is caused by the moisture contained in the glass raw material, and then, in order to suppress the aggregation of the cerium, it is only necessary to reduce the water contained in the glass raw material. That is, the amount of ortho-boric acid containing a large amount of water molecules in the Φ sub-score can be reduced, and the amount of boric anhydride can be increased. Further, regarding the problem of (2), the inventors have found that the glass raw material input port is heated. Boric acid loses one water molecule and becomes metaboric acid. The metaboric acid which is liquefied at 150 ° C or higher is aggregated with an alkaline earth metal compound, and then, in order to suppress the aggregation of the metaboric acid and the alkaline earth metal compound, the use is contained. The boron source of the boric anhydride in the state in which the water molecules are lost in the boric acid may be used. Further, by using a boron source containing boric anhydride, an effect of -11 - 1377181 or less can be expected. (i) Since the amount of water in the glass raw material is suppressed, the heat of vaporization of the water when the glass raw material is melted is reduced. Therefore, the energy consumed in the melting kiln reduces the amount of heat of vaporization due to the decrease in vaporization heat, and it is possible to save energy and improve productivity. (ii) When the amount of water (yS - 0H) in the molten glass is reduced. When C1 is contained in the clarifying agent, φ volatilization can be suppressed by the following reaction to become HC1'. Therefore, the amount of the clarifying agent can be reduced, and the burden of the exhaust treatment containing HC1 is further reduced. Oir + cr—hci +〇2·. (iii) The metaboric acid formed by the loss of one water molecule from orthoboric acid is volatile, and since the boric anhydride is not easily volatilized, the amount of the boron source can be reduced, and the burden of the exhaust treatment containing metaboric acid can be further reduced. Therefore, in the present invention, as the boron source, a boronic anhydride having a boron source of 100% by mass (calculated as B2〇3) containing 10 to 100% by mass (calculated as b2o3 for φ) is used. By controlling the boric anhydride at 10% by mass or more, it is possible to suppress the aggregation of the glass raw material, reduce the effect of the bubble, and improve the homogeneity and flatness. The boric anhydride is preferably 20 to 1% by mass, more preferably 50 to 100% by mass, and particularly preferably 1% by mass. As a boron compound other than boric anhydride, it is preferable to use orthoboric acid from the viewpoint of being inexpensive and easy to obtain. (Other raw materials) As other raw materials, Al2〇3 and soil-based metal oxides (-12-1377181)

Mg0、Ca0、Sr0、Ba0) 、A1(0H)3、驗土化物（Mg(OH) 2、Ca(OH) 2、Ba(OH) 2、 )° 本發明中，使玻璃母材組成原料中含有鋁 ' 屬的氫氧化物一事，在將玻璃原料熔融之步顆 ))中促進初期熔融，可在更低溫下得到熔融理想。又，於本發明中，亦可使玻璃母材組成 φ 鋁及鹼土類金屬所構成之氫氧化物。又，如上述，爲了減少熔融玻璃中之水分璃原料中之硼源的一部份或全部使用硼酸酐，之水分量會過份降低，於減壓脫泡步驟中泡則的浮出速度降低，無鹼玻璃的均質性及平坦度能性。此種場合，爲補給熔融玻璃中之水分量或驗土類金屬之氫氧化物爲佳。作爲氫氧化物，以使用A1 ( 0H ) 3 —事， φ 被促進之面爲理想。又，作爲鹼土類金屬之氫使用Mg(〇H) 2或Ca(OH) 2之至少一方爲 • 使用Mg(〇H) 2爲佳。在玻璃母材組成原料中使其含有鹼土類金物時之含有量，在鹼土類金屬源莫耳％ (J ，唯Μ爲鹼土類金屬元素）之中，以15〜100 ΜΟ換算）之範圍爲佳。藉由氫氧化物之添加量 %以上，於步驟（a )中，可減低矽砂中所含之的未熔解量。因此，於玻璃熔液中泡發生時，類金屬氫氧 Sr ( OH ) 2 或鹼土類金 I (步驟（a 玻璃之面爲原料中含有量，若將玻熔融玻璃中會變小，泡有惡化之可，以添加銘在初期熔融氧化物，以佳、特別係屬之氫氧化以MO換算莫耳％以（ t爲15莫耳 S i 〇2成分可防止未熔 -13- 解之Si 〇2被此泡捲入而在玻璃熔液之表層附近聚集。然後其結果，玻璃熔液之表層與表層以外的部份之間，Si〇2 的組成比產生差異，可防止玻璃的均質性及平坦性降低。又’因隨著鹼土類金屬源中之氫氧化物的莫耳比增加 ’則玻璃原料熔解時之Si02成分的未熔解量降低，所以氫氧化物的莫耳比越高越好。又，與上述鹼土類金屬氫氧化物的場合時相同之理由 ’使玻璃母材組成原料中含有Α1(〇Η) 3時之含有量，鋁源100莫耳％ (以Al2〇3換算）之中，以15〜100莫耳％ (以ai2o3換算）之範圍爲佳。又，因隨著鋁源中之氫氧化物的莫耳比增加，則玻璃原料熔解時之Si02成分的未融解量降低，所以氫氧化物之莫耳比越高越好。 (玻璃母材組成原料）玻璃母材組成原料係爲將前述各原料予以混合之粉末狀的混合物。玻璃母材組成原料爲調製成爲具有作爲目標之玻璃母材組成之無鹼玻璃。玻璃母材組成原料之組成，以成爲後述之玻璃母材組成（1)之無鹼玻璃之組成爲佳，以成爲後述之玻璃母材組成（2)或玻璃母材組成（3)之無鹼玻璃之組成爲特佳 -14- 1377181 (澄清劑）澄清劑係爲改善澄清性之成分，添加於玻璃母材組成原料中。本發明中，作爲澄清劑，至少使用Sn02 » ' Sn氧化物，在1400°C以上之高溫下價數從Sn02 (Mg0, Ca0, Sr0, Ba0), A1(0H)3, soil tester (Mg(OH) 2, Ca(OH) 2, Ba(OH) 2)) In the present invention, the glass base material is composed of raw materials. In the case of containing a hydroxide of the genus Aluminium, the initial melting is promoted in the step of melting the glass raw material, and it is preferable to obtain the melting at a lower temperature. Further, in the present invention, the glass base material may be composed of a hydroxide composed of φ aluminum and an alkaline earth metal. Further, as described above, in order to reduce the use of boric anhydride in a part or all of the boron source in the glass raw material in the molten glass, the amount of water is excessively lowered, and the floating speed of the bubble is lowered in the vacuum degassing step. , the homogeneity and flatness energy of alkali-free glass. In this case, it is preferable to supply the amount of water in the molten glass or the hydroxide of the soil-like metal. As the hydroxide, it is preferable to use A1 (0H) 3 as the surface on which φ is promoted. Further, as the hydrogen of the alkaline earth metal, at least one of Mg(〇H) 2 or Ca(OH) 2 is used. • It is preferable to use Mg(〇H) 2 . When the content of the alkali metal-based gold material is contained in the raw material of the glass base material, the range of the alkaline earth metal source Moer % (J, only the alkaline earth metal element) is in the range of 15 to 100 ΜΟ. good. By the addition amount of the hydroxide or more, in step (a), the amount of unmelted contained in the strontium sand can be reduced. Therefore, when the bubble occurs in the glass melt, the metal hydroxide-like Sr ( OH ) 2 or the alkaline earth gold I (step (a glass surface is contained in the raw material, if the glass molten glass becomes smaller, the bubble has Deterioration can be added to the initial molten oxide, which is better than the special hydrogen hydroxide in terms of MO in terms of MO. (t is 15 moles of S i 〇2 component to prevent unmelted-13-solution Si 〇2 is entangled by the bubble and gathers near the surface layer of the glass melt. Then, as a result, the composition ratio of Si〇2 is different between the surface layer of the glass melt and the surface layer, and the homogeneity of the glass can be prevented. And the flatness is lowered. Further, 'the molar ratio of the hydroxide in the alkaline earth metal source increases', the unmelted amount of the SiO 2 component at the time of melting the glass raw material is lowered, so the higher the molar ratio of the hydroxide In the case of the above-mentioned alkaline earth metal hydroxide, the reason is as follows: the content of the glass base material composition containing Α1 (〇Η) 3, and the aluminum source 100 mol% (in terms of Al2〇3) Among them, the range of 15 to 100 mol% (in terms of ai2o3) is Further, as the molar ratio of the hydroxide in the aluminum source increases, the amount of the SiO2 component which is not melted when the glass raw material is melted is lowered, so that the higher the molar ratio of the hydroxide is, the better. The raw material of the glass base material is a powdery mixture in which the respective raw materials are mixed. The raw material of the glass base material is prepared into an alkali-free glass having a target glass base material composition. The glass base material is composed of a raw material. The composition of the alkali-free glass which is the glass base material composition (1) to be described later is preferable, and the composition of the alkali-free glass which is a glass base material composition (2) or a glass base material composition (3) to be described later is particularly preferable. -14- 1377181 (clarifying agent) A clarifying agent is added to a raw material of a glass base material to improve the clarity. In the present invention, at least 1200 ° C or more is used as a clarifying agent. Price at high temperatures from Sn02 (

Sn4+ )變化爲SnO ( Sn2+ )。伴隨著該價數的變化，釋放出澄清氣體（氧氣）。接著一定比例以上之Sn02價數變 φ 化爲SnO，因充份的澄清氣體被放出，有效果的澄清則成爲可能。錫的添加量，相對於玻璃母材組成原料在Sn02換算下以0.0 1〜2質量·％爲佳，以0 · 1〜0 · 7質量％爲更佳。藉由使錫的添加量在0.01質量％以上，可充份地進行澄清。藉由使錫的添加量在2質量％以下，可抑制未熔錫等缺點產生。作爲其他澄清劑，相對於玻璃母材組成原料，更進一 φ 步，亦可添加選自由在C1換算下3質量％以下之氯化物、以S03換算下3質量％以下之硫酸鹽及以F換算下3質量 . %以下之氟化物所成群之1種以上’合計量爲〇·〇1〜5質量％。尙，因玻璃屑之處理需要多數的人力，除了不可避免的混入物外以不含有Pb〇、As203、Sb203等之雜質爲佳 (玻璃屑）玻璃屑係爲，於無鹼玻璃之製造過程中所排出之玻璃 -15- 1377181 碎屑。作爲玻璃屑，以含有與作爲目標之_ 材組成相同之組成者爲佳。玻璃屑之添加量，相對於玻璃母材糸j 3 00質量％爲佳。藉由使玻璃屑之添加量，可確保初期熔融性。藉由使玻璃屑之箱 %以下，可發揮S η 0 2所產生之澄清效果。 (其他添加劑）使用玻璃屑之場合時，以同時加入硝於玻璃屑中，作爲澄清劑所用之Sn (Sn2+ )之狀態下所存在之比例爲多，產力降低。因此，於玻璃屑的再熔融時藉往藉由硝酸鹽使SnO(Sn2+)氧化爲Sn02 再度添加Sn02於玻璃屑中，而進行有效t φ 硝酸鹽之添加量，相對於玻璃母材徒算下以0.01〜10質量％爲佳。藉由使硝 • 0.01質量％以上，可有效率地使玻璃屑中Sn4+) changes to SnO (Sn2+). A clarified gas (oxygen) is released along with the change in the valence. Then, a certain percentage or more of the Sn02 valence is changed to SnO, and since sufficient clarified gas is released, effective clarification becomes possible. The amount of tin added is preferably 0.01 to 2 mass% in terms of Sn02, and more preferably 0 to 1 to 0.7% by mass based on the glass base material. By making the amount of tin added in an amount of 0.01% by mass or more, clarification can be sufficiently performed. When the amount of tin added is 2% by mass or less, defects such as unmelted tin can be suppressed. Further, as the other clarifying agent, the raw material of the glass base material may be further added to a φ step, and a salt selected from the group consisting of a chloride content of 3 mass% or less in terms of C1 and a mass ratio of 3 mass% or less in terms of S03 may be added and converted in F. One or more of the following three masses or less of the fluorides are in a total amount of 〇·〇1 to 5 mass%.尙因因因因因因因因因因因因因因因因因因因因因玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃玻璃The discharged glass -15 - 1377181 debris. As the glass cullet, it is preferred to contain the same composition as the target material. The amount of the glass swarf added is preferably 3% by mass based on the glass base material. The initial meltability can be ensured by adding the amount of glass cullet. By making the glass swarf box less than or equal to %, the clarifying effect by S η 0 2 can be exhibited. (Other additives) When glass swarf is used, the ratio of Sn (Sn2+) used as a clarifying agent is large in the case where glass nitrite is simultaneously added, and the productivity is lowered. Therefore, in the remelting of the glass cullet, the SnO(Sn2+) is oxidized to Sn02 by the nitrate to add Sn02 to the glass cullet, and the effective amount of the φ nitrate is added, which is calculated relative to the glass matrix. It is preferably 0.01 to 10% by mass. By making the nitrate 0.01% by mass or more, it is possible to efficiently make the glass swarf

Sn02。就算使硝酸鹽之添加量爲超過10 之氧化已爲飽和，效果爲小。步驟（ii)： (步驟（a )) 步驟（a )係初期熔融步驟，係爲將 S鹼玻璃的玻璃母 .成原料，以1 5〜爲15質量％以上 :加量爲3 0 0質量酸鹽爲佳。氧化物係以SnO ;生澄清氣體之能 J添加硝酸鹽，因 (Sn4+)，可不用澄清。 L成原料，N〇3換酸鹽之添加量爲之SnO氧化成爲質量％，對 Sn02 玻璃原料熔融使 -16- 1377181 其均勻地玻璃化之步驟。步驟（a)中之溫度係爲使熔融玻璃之黏度爲超過 102'4dPa_ s之溫度，以熔融玻璃之黏度成爲1025dpa· s 以上之溫度爲佳，熔融玻璃之黏度爲1〇2.6〜1〇2 9dPa · s 之溫度爲更佳。若使熔融玻璃之黏度超過1〇2.9dPa. s,初期熔融會變成難以均質。因此，以成爲1〇2 9dPa . s以下之溫度爲佳。又，步驟（a)中溫度係以1400 °C以上爲佳〇藉由使步驟（a)中溫度成爲使熔融玻璃之黏度超過 1 0 2 4 dPa · s之溫度，可一邊抑制Sn02的消耗，一邊進行玻璃化。因此，後段之步驟（b )中可有效地進行澄清，可減少玻璃中之泡。如此一般本發明中，因作爲澄清劑至少使用Sn02，有將玻璃原料在比較的低溫下，即使熔融玻璃之黏度爲超過1 02 4dPa · s之溫度下加熱使成爲熔融玻璃之必要。但，作爲硼源若僅使用正硼酸，該溫度下因矽砂容易聚集，則熔融玻璃內容易產生未熔之二氧化矽。另一方面，於本發明中，玻璃母材組成原料因含有硼酸酐作爲硼源，就算在該溫度下玻璃原料可均勻熔融，未融二氧化矽之產生也被抑制。步驟（a)之時間以 100〜900分爲佳，以 150〜500 分爲更佳。 (步驟（b )) -17- 1377181 步驟（b)係澄清步驟，將熔融玻璃在比較高，即使熔融玻璃之黏度爲1024dPa· s以下之溫度比前述步驟（a)中溫度高3(TC以上之溫度下加熱 Sn之價數變化使澄清氣體產生，將熔融玻璃中之 ' 脫泡之步驟。步驟（b)中之溫度，係爲使熔融玻璃之 102 4dPa · s以下之溫度，以使熔融玻璃之黏度爲1 φ · s以下之溫度爲佳，以使熔融玻璃之黏度爲 102 2dPa· s之溫度爲更佳。若使熔融玻璃之黏度 10l8dPa · s，則爐材變的容易受到侵蝕，變的容易陷。因此，以101 8dPa · s以上之溫度爲佳。Sn02. Even if the amount of nitrate added is more than 10, the oxidation is already saturated, and the effect is small. Step (ii): (Step (a)) Step (a) is an initial melting step of forming a glass mother of S alkali glass into a raw material of 15 to 15% by mass or more: an amount of 300 mass. The acid salt is preferred. The oxide is made of SnO; the energy of the clarified gas is J. The nitrate is added, and since (Sn4+), it is not necessary to clarify. The amount of the L-forming material and the N?3-changing acid salt is such that the SnO is oxidized to a mass %, and the Sn02 glass raw material is melted to uniformly vitrify -16-1377181. The temperature in the step (a) is such that the viscosity of the molten glass exceeds 102'4dPa_s, and the viscosity of the molten glass becomes 1025dpa·s or more, and the viscosity of the molten glass is 1〇2.6~1〇2. The temperature of 9dPa · s is better. If the viscosity of the molten glass exceeds 1 〇 2.9 dPa·s, the initial melting becomes difficult to homogenize. Therefore, it is preferable to set the temperature to be 1 〇 2 9 dPa·s or less. Further, in the step (a), the temperature is preferably 1400 ° C or higher, and the temperature in the step (a) is such that the viscosity of the molten glass exceeds a temperature of 10 24 dPa · s, whereby the consumption of Sn 02 can be suppressed. It is vitrified. Therefore, the clarification can be effectively carried out in the step (b) of the latter stage, and the bubbles in the glass can be reduced. As described above, in the present invention, at least Sn02 is used as the clarifying agent, and it is necessary to heat the glass raw material at a relatively low temperature, even if the viscosity of the molten glass is higher than 1200 dPa·s. However, if only boronic acid is used as the boron source, unmelted cerium oxide is likely to be generated in the molten glass because the cerium is easily aggregated at this temperature. On the other hand, in the present invention, the raw material of the glass base material contains boronic anhydride as a boron source, and even at this temperature, the glass raw material can be uniformly melted, and the generation of unmelted cerium oxide is also suppressed. The time of step (a) is preferably divided into 100 to 900, and is preferably divided into 150 to 500. (Step (b)) -17- 1377181 Step (b) is a clarification step in which the molten glass is relatively high, even if the viscosity of the molten glass is 1024 dPa·s or less, which is higher than the temperature in the above step (a) by 3 (TC or more). The temperature is heated to change the valence of Sn to cause the clarified gas to be generated, and the step of defoaming in the molten glass. The temperature in the step (b) is such that the molten glass is at a temperature of 102 dPa·s or less to melt The viscosity of the glass is preferably 1 φ · s or less, so that the viscosity of the molten glass is preferably 102 2 dPa·s. If the viscosity of the molten glass is 10 l8 dPa · s, the furnace material is easily corroded. It is easy to get trapped. Therefore, it is better to have a temperature of 101 8 dPa · s or more.

又，步驟（b )中之溫度，係爲比前述步驟（a 度高3 0 °C以上之溫度，以比前述步驟（a )中之溫！ °C以上之溫度爲佳，以比前述步驟（a )中溫度高上之溫度爲更佳。又，步驟（b )中溫度以170CTC • 佳。藉由將步驟（b)中之溫度成爲使溶融玻璃之 • 102 4dPa . s以下之溫度，且比前述步驟（a)中之 3 0 °C以上之溫度，則澄清氣體可效率地產生，可有進行澄清，可減少玻璃中之泡。步驟（b)之時間，以60〜800分爲佳，120〜爲更佳。熔融玻璃之黏度係使用高溫回轉黏度計進行測: 的溫度下，且，藉由泡進行黏度爲 02 3dPa 1 01 8 〜爲未滿產生缺 )中溫隻高50 7 0°C 以以下爲 a 黏度爲溫度商效率地 3 00分 -18- 1377181 步驟（iii )、步驟（iv): 步驟（iii)及步驟（iv)中、與公知之無鹼玻璃之製造方法同樣地進行成形、緩冷卻及切斷》 <無鹼玻璃> 使用本發明之製造方法所得之無鹼玻璃，其玻璃母材組成中含有源自矽砂之Si02、及源自硼源之B203。無鹼 φ 玻璃係爲，實質上不含有Na20、K20等之鹼金屬氧化物者。在此，實質上不含有鹼金屬氧化物係指、除了從原料等混入不可避免之雜質外，不含有鹼金屬氧化物。即，意指不蓄意使其含有鹼金屬氧化物者。以下，進行說明關於無鹼玻璃之理想的玻璃母材組成玻璃母材組成（1 ): 無鹼玻璃，具有作爲液晶顯示基板用玻璃之特性（熱膨脹係數25χ1(Γ7〜60xl(T7/t：)、耐藥品性、耐久性等 )、從適合成型爲板玻璃之觀點來看，以氧化物爲基準之質量百分比表示下’以下述玻璃母材組成（1)之無鹼玻璃爲佳。Further, the temperature in the step (b) is higher than the temperature in the above step (a degree higher than 30 ° C, more preferably than the temperature in the above step (a): ° C or more, in comparison with the above steps (a) The temperature in the middle temperature is preferably higher. Further, the temperature in the step (b) is preferably 170 CTC. By setting the temperature in the step (b) to a temperature lower than 102 4 dPa·s of the molten glass, And than the temperature above 30 ° C in the above step (a), the clarified gas can be efficiently generated, and clarification can be performed to reduce the bubbles in the glass. The time of the step (b) is divided into 60 to 800. Good, 120~ is better. The viscosity of the molten glass is measured at a temperature using a high-temperature rotary viscometer, and the viscosity by the bubble is 02 3dPa 1 01 8 ~ is insufficient to produce a shortage) 70 ° C with the following a viscosity as a temperature quotient 30,000 points -18 - 1377181 Step (iii), step (iv): Step (iii) and step (iv), and the production of known alkali-free glass The method is similarly carried out, slow cooling, and cutting" <alkali-free glass> using the manufacture of the present invention Law resulting alkali-free glass, a glass base material comprising silica sand of the composition from Si02, B203, and derived from the source of boron. The alkali-free φ glass is a substance which does not substantially contain an alkali metal oxide such as Na20 or K20. Here, the alkali metal oxide is not substantially contained, and an alkali metal oxide is not contained except that impurities which are unavoidable are mixed from a raw material or the like. That is, it means that it does not intentionally contain an alkali metal oxide. In the following, an example of a glass base material composition (1) for an alkali-free glass is described. The alkali-free glass has characteristics as a glass for a liquid crystal display substrate (thermal expansion coefficient 25χ1 (Γ7 to 60xl (T7/t:)). From the viewpoint of suitable molding into a sheet glass, the mass percentage based on the oxide means that the alkali-free glass of the following glass base material composition (1) is preferable.

Si02: 50 〜66 質量％、Al2〇3: 10.5 〜22 質量％、B2O3 :5〜12質量％、1^笆〇:0〜8質量％、€3〇:0〜14.5質量。/〇、SrO: 0〜24 質量％、BaO: 〇〜13.5 質量％、MgO + CaO + SrO + BaO:9 〜29.5質量％ . . · ( ι ) 〇 1377181 玻璃母材組成（2 ): 無鹼玻璃，其應變點爲640 °C以上，熱膨脹係數、密度爲小，可抑制蝕刻所使用之緩衝級氫氟酸（B HF )所造 ' 成之白濁，對鹽酸等之藥品之耐久性也爲優良，熔融.成型爲容易，從適合浮式法成型之觀點來看，以氧化物爲基準之質量百分比表示下、以下述玻璃母材組成（2)之無 φ 鹼玻璃爲更佳。Si02: 50 to 66% by mass, Al2〇3: 10.5 to 22% by mass, B2O3: 5 to 12% by mass, 1^笆〇: 0 to 8% by mass, €3〇: 0 to 14.5 mass. /〇, SrO: 0 to 24% by mass, BaO: 〇~13.5% by mass, MgO + CaO + SrO + BaO: 9 to 29.5 mass% . · ( ι ) 〇1377181 Glass base material composition (2 ): alkali-free The glass has a strain point of 640 ° C or higher, a small thermal expansion coefficient and a low density, and can suppress the white turbidity caused by the buffer-grade hydrofluoric acid (B HF ) used for etching, and the durability to chemicals such as hydrochloric acid is also It is excellent, and it is easy to form by melting. From the viewpoint of suitable float molding, it is more preferable that the φ-free alkali glass of the following glass base material composition (2) is represented by the mass percentage based on the oxide.

Si02: 58 〜66 質量％、Al2〇3: 15 〜22 質量％、B2〇3 :5〜12質量％、MgO: 0〜8質量％、CaO: 0〜9質量％、 SrO ： 3 〜12.5 質量％、BaO ： 0〜2 質量％、MgO + CaO + SrO + BaO:9〜18 質量％ . . . (2)。說明關於本組成系之各組成。藉由使Si 02爲58質量％以上，無鹼玻璃的應變點上升，耐藥品性變的良好，熱膨脹係數降低。藉由使Si02 φ 爲66質量％以下，玻璃之熔融性變的良好，失透特性變的良好。 . ai2o3爲抑制無鹼玻璃之分相，降地熱膨脹係數’提高應變點。藉由使Al2〇3爲15質量％以上’可以發現上述效果。藉由使Al2〇3爲22質量％以下’玻璃之熔融性則變的良好〇 B2〇3爲抑制由BHF造成之無鹼玻璃之白濁’並不提升高溫下之黏性，降低無鹼玻璃之熱膨脹係數及密度。 -20- 137.7181 藉由使B2〇3爲5質量％以上，無鹼玻璃之耐BHF性變的良好。藉由使B2〇3爲12質量％以下，無鹼玻璃之耐酸性變的良好，應變點也同時上升。Si02: 58 to 66% by mass, Al2〇3: 15 to 22% by mass, B2〇3: 5 to 12% by mass, MgO: 0 to 8% by mass, CaO: 0 to 9% by mass, SrO: 3 to 12.5 by mass %, BaO: 0 to 2% by mass, MgO + CaO + SrO + BaO: 9 to 18% by mass . . . (2). Explain the composition of the composition. When the Si 02 is 58% by mass or more, the strain point of the alkali-free glass rises, the chemical resistance is improved, and the thermal expansion coefficient is lowered. When the SiO 2 φ is 66% by mass or less, the meltability of the glass is improved, and the devitrification property is improved. Ai2o3 is to suppress the phase separation of the alkali-free glass, and the geothermal expansion coefficient increases the strain point. The above effect can be found by making Al2〇3 15% by mass or more. When Al2〇3 is 22% by mass or less, 'the meltability of the glass is improved, 〇B2〇3 is to suppress the white turbidity of the alkali-free glass caused by BHF', and the viscosity at high temperature is not improved, and the alkali-free glass is lowered. Thermal expansion coefficient and density. -20- 137.7181 When B2〇3 is 5% by mass or more, the BHF resistance of the alkali-free glass is good. When B2〇3 is 12% by mass or less, the acid resistance of the alkali-free glass is improved, and the strain point is also increased.

MgO爲抑制無鹼玻璃之熱膨脹係數、密度之上昇’使 * 玻璃原料之熔融性提升。藉由使MgO爲8質量％以下，可抑制由BHF造成爲之白濁，抑制無鹼玻璃之分相。 φ CaO爲提升玻璃原料之熔融性。藉由使CaO爲9質量％以下，無鹼玻璃之熱膨脹係數降低，失透特性變的良好。MgO is to suppress the increase in the thermal expansion coefficient and density of the alkali-free glass, and to improve the meltability of the glass raw material. When MgO is 8% by mass or less, white turbidity caused by BHF can be suppressed, and phase separation of the alkali-free glass can be suppressed. φ CaO is the melting property of the glass raw material. When CaO is 9% by mass or less, the thermal expansion coefficient of the alkali-free glass is lowered, and the devitrification property is improved.

SrO爲抑制無鹼玻璃之分相，抑制由BHF造成之無鹼玻璃之白濁。藉由使SrO爲3質量％以上，可發現上述效果。藉由使SrO爲12.5質量％以下，無鹼玻璃之熱膨脹係數降低。SrO suppresses the phase separation of the alkali-free glass and suppresses the white turbidity of the alkali-free glass caused by BHF. The above effects can be found by making SrO 3 mass% or more. When the SrO is 12.5% by mass or less, the coefficient of thermal expansion of the alkali-free glass is lowered.

BaO爲抑制無鹼玻璃之分相，提升熔融性，且提升失 φ 透特性。藉由使BaO爲2質量％以下，降低無鹼玻璃之密度， .降低熱膨脹係數。但，若考慮對環境的負擔，以實質上不含有爲佳。藉由使MgO + CaO + SrO + BaO爲9質量％以上，玻璃之熔融性變的良好。藉由使Mg〇 + Ca〇 + SrO + BaO爲18質量 %以下，則無鹼玻璃之密度降低。玻璃母材組成（3 ): -21 -BaO suppresses the phase separation of alkali-free glass, improves the meltability, and improves the φ permeability. When BaO is 2% by mass or less, the density of the alkali-free glass is lowered, and the coefficient of thermal expansion is lowered. However, if you consider the burden on the environment, it is better not to contain it. When the MgO + CaO + SrO + BaO is 9% by mass or more, the meltability of the glass is improved. When Mg 〇 + Ca 〇 + SrO + BaO is 18% by mass or less, the density of the alkali-free glass is lowered. Glass base material composition (3): -21 -

1377181 無鹼玻璃，從作爲液晶顯示基板用玻璃其之转 ’耐還原性、均質性、抑制泡爲優、適合經浮式g 之觀點來看，以氧化物基準之質量百分比表示下，玻璃母材組成（3)之無鹼玻璃爲特佳。 31〇2:50〜61.5質量％、八12〇3:10.5〜18 | B2O3 : 7 〜1 0 質量％、MgO : 2 〜5 質量％、CaO : 質量°/。、81'〇:0〜24質量°/。、83〇:0〜13.5質量％ CaO + SrO + BaO ： 16 〜29.5 質量％ ... (3) » 說明關於本組成系之各組成。藉由使Si 02爲50質量％以上，則無鹼玻璃之變的良好、密度下降、應變點上升、熱膨脹係數T 氏模數上升。藉由使Si02爲61.5質量％以下，貝! 璃之失透特性變的良好。 ai2o3爲抑制無鹼玻璃之分相，提升應變點，氏模數。藉由使Al2〇3爲10.5質量％以上，則可發現_ 。藉由使Al2〇3爲18質量％以下，無鹼玻璃之失今耐酸性及耐BHF性變的良好。 B2〇3爲降低無鹼玻璃之密度，提升耐BHF \ 熔融性，失透特性變的良好’使熱膨脹係數下降。藉由使B2〇3爲7質量％以上’可發現上述效J 使B2〇3爲10質量％以下’無鹼玻璃之應變點上3 模數上升，耐酸性變的良好。1377181 Epoxy-free glass, from the viewpoint of conversion resistance, homogeneity, suppression of bubbles, and float g as a glass for liquid crystal display substrates, based on the mass percentage of oxides, The alkali-free glass of the material composition (3) is particularly excellent. 31〇2: 50~61.5 mass%, eight 12〇3:10.5~18 | B2O3: 7~1 0 mass %, MgO: 2 〜5 mass %, CaO: mass °/. , 81' 〇: 0~24 mass ° /. 83〇: 0 to 13.5 mass% CaO + SrO + BaO : 16 to 29.5 mass % ... (3) » Explain the composition of the composition. When Si 02 is 50% by mass or more, the alkali-free glass is improved, the density is lowered, the strain point is increased, and the coefficient of thermal expansion T is increased. When the SiO 2 is 61.5 mass% or less, the devitrification property of the glass is good. Ai2o3 is to suppress the phase separation of alkali-free glass and increase the strain point and modulus. When Al2〇3 is made at 10.5% by mass or more, _ can be found. When Al2〇3 is 18% by mass or less, the alkali-free glass is excellent in acid resistance and BHF resistance. B2〇3 reduces the density of the alkali-free glass, improves the resistance to BHF\meltability, and deteriorates the devitrification property, which decreases the coefficient of thermal expansion. When B2〇3 is 7 mass% or more, it is found that the above effect J makes B2〇3 10% by mass or less. The 3 modulus increases at the strain point of the alkali-free glass, and the acid resistance is improved.

MgO爲使無鹼玻璃之密度降低’且不提高熱月 ;性優良 :所成型以下述 f 量〇/〇、 0 〜14.5 、M g Ο + .耐酸性降、楊丨無鹼玻提升楊 .述效果 :特性、，提升 :。藉由 1楊氏脹係數 -22- 1377181 ，使應變點不過大地降低，且使熔融性提升。藉由使MgO爲2質量％以上，可發現上述效果。藉由使MgO爲5質量％以下，則無鹼玻璃之分相被抑制，失透特性、耐酸性及耐BHF性變的良好。 ' CaO爲並不使無鹼玻璃之密度提高，不使熱膨脹係數提高，不使應變點過大地降低，提升熔融性。藉由使CaO爲14.5質量％以下，無鹼玻璃之失透特性 φ 變的良好，熱膨脹係數降低，密度降低，耐酸性及耐鹼性變的良好。MgO is to reduce the density of alkali-free glass' and does not increase the heat month; it is excellent: it is formed by the following f amount 〇 / 〇, 0 ~ 14.5, M g Ο +. Acid resistance, Yang 丨 alkali-free glass to enhance Yang. Description effect: feature, promotion: With a Young's expansion coefficient of -22 - 1377181, the strain point is not greatly reduced, and the meltability is improved. The above effect can be found by making MgO 2% by mass or more. When MgO is 5% by mass or less, the phase separation of the alkali-free glass is suppressed, and the devitrification property, acid resistance, and BHF resistance are improved. 'CaO does not increase the density of the alkali-free glass, does not increase the coefficient of thermal expansion, does not reduce the strain point excessively, and improves the meltability. When CaO is 14.5% by mass or less, the devitrification property φ of the alkali-free glass is improved, the coefficient of thermal expansion is lowered, the density is lowered, and the acid resistance and alkali resistance are improved.

Sr 0爲不使無鹼玻璃之密度提高，不使熱膨脹係數提高，不使應變點過大地降低，提升熔融性。藉由使SrO爲24質量％以下，無鹼玻璃之失透特性變的良好，熱膨脹係數降低，密度降低，耐酸性及耐鹼性變的良好。Sr 0 is such that the density of the alkali-free glass is not increased, the coefficient of thermal expansion is not increased, and the strain point is not excessively lowered to improve the meltability. When SrO is 24% by mass or less, the devitrification property of the alkali-free glass is improved, the coefficient of thermal expansion is lowered, the density is lowered, and the acid resistance and alkali resistance are improved.

Ba◦爲抑制無鹼玻璃之分相，使失透特性提升，使耐 φ 藥品性提升。藉由使BaO爲13.5質量％以下，無鹼玻璃之密度降低 . ，熱膨脹係數降低，楊氏模數提升，熔融性變的良好，耐 B H F性變的良好。但，若考慮對環境的負擔，以實質上不含有爲佳。藉由使MgO + CaO + SrO + BaO爲16質量％以上，玻璃之熔融性變的良好。藉由使MgO + CaO + SrO + BaO爲 29.5 質量％以下，無鹼玻璃之密度、熱膨脹係數下降。藉由以上所說明之本發明之無鹼玻璃之製造方法，作 -23- 1377181 爲前述矽砂，D 5〇爲15〜60 μιη’且使用粒徑100 μιη以上之粒子的比例爲2.5體積％以下者，作爲硼源，使用硼源 1〇〇質量％ (以β2ο3換算）之中，含有硼酸酐10〜100質量％ (以Β2〇3換算）者，作爲澄清劑，至少使用Sn02，因玻璃原料之熔融係以至少上述之步驟（a)、步驟（b) 之2步驟進行，可得到玻璃中之泡爲少，均質性、平坦度爲高之無鹼玻璃。〔實施例〕以下舉出實施例來具體說明本發明，但當然地本發明並不應受此些實施例所限定而被解釋。例1、2爲表示低溫熔融性之實驗例、例3〜5、7、8 爲實施例、例6爲比較例。〔例1〕以氧化物基準之質量百分比表示下，使成爲具有Si02 :60 質量％、a1203 : 1 7 質量％、B2〇3 : 8 質量％、MgO : 3質量％、c a 0 : 4質量％、S r Ο : 8質量％之玻璃母材組成之無鹼玻璃，矽砂1(〇5〇:27μιη、粒徑ΙΟΟμηι以上之粒子之比例：0體積％、D99 (粒度分佈中之體積頻度佔有 99%之粒子徑）：69μιη。），作爲硼源以硼酸酐（1 〇〇質 4 0/0} ’作爲鋁源以αι203，及調製其他之原料使成玻璃 S材組成原料，更進一步作爲澄清劑，相對於該玻璃母材組成原料，添加0.5質量％之Sn〇2、0.5質量％之SrCl4及 -24- 1377181 0.3質量％之CaS04. 2H20，使成爲玻璃原料。將玻璃化後之質量爲成爲250g之量之玻璃原料放入高90mm、外徑70mm之有底圓筒形之銷铑製j；甘鍋。將該坩鍋放入加熱爐，一邊從加熱爐的側面吹入露點爲60 °C之 ' 空氣，在1 525 °C (熔融玻璃之黏度成爲1〇2 6dPa · s之溫度）下加熱30分後，藉由攪拌器強制的在坩鍋內攪拌30 分鐘，使玻璃原料熔融後。其後，停止攪拌，靜置60分 φ 鐘，坩鍋內之熔融玻璃流出至碳板上，在緩冷卻爐中冷卻。冷卻後，將樣品從緩冷卻爐中取出，從樣品的邊緣一邊以光照射，藉由實體顯微鏡，一邊計數未熔二氧化矽之數目"結果如表1所示。又，使玻璃原料之熔融溫度成爲1550 °C (熔融玻璃之黏度成爲1025dPa. s之溫度）實施了相同之評價。結果如表1所示。〔例2〕除了將矽砂1取代爲使用矽砂2 ( D5〇 : 39μιη、粒徑 ΙΟΟμιη以上之粒子之比例：4.2體積％、D99: 153μιη)、作爲硼源使用了正硼酸（1 〇〇質量％ )以外，與例1進行了相同的評價。結果如表1所示。 -25- 1377181 〔表1〕熔融溫度 (°C) 熔融玻璃之黏度 (dPa . s) 未融一氧化砂量（個/kg) 例1 例2 矽砂1+硼酸酐矽砂2+正硼酸 1525 1025 757 1230 1550 1025 188 1021 將本發明之構成（D5〇: 15〜60μπι、粒徑ΙΟΟμπι以上之粒子之比例：2.5體積％以下）之矽砂1與硼酸酐之組 ^ 合，與本發明之構成相異之矽砂2與正硼酸之組合相比較後，得知未融二氧化矽之量爲少，且在更低溫下可進行初期溶解。又，由於未融二氧化矽之量爲少，均質性爲高之玻璃。又，可得到將板玻璃成型時其平坦度爲高之玻璃。〔例3〕與例1相同之玻璃母材組成原料’更進一步作爲澄清劑，相對於該玻璃母材組成原料’添加〇.5質量％的Sn〇2 ，使成玻璃原料。步驟（a): 將該玻璃原料之半量（以玻璃換算相當於125g)放入 300cc之鉑坩鍋，在1500 °C (熔融玻璃之黏度成爲 1027dPa .s之溫度）之電爐中靜置30分鐘。暫且從電爐中取出鉑坩鍋，追加剩下的另一半量（以玻璃換算相當於 1 2 5 g )，再次靜置於l5〇〇C (熔融玻璃之黏度成爲 1027dPa. s之溫度）之谦爐中30分鐘使玻璃原料溶融。 -26- 1377181 步驟（b): 其後，迅速轉移至1590 °C (熔融玻璃之黏度成爲 102 3dPa. s之溫度）之電爐，靜置30分鐘。其後，轉移至730 °C之電爐，花費2小時使玻璃緩冷卻至610 °C，更進一步’約花費10小時使玻璃緩冷卻至室溫。然後，將坩鍋之上方中央的玻璃以取心鑽貫穿直徑3 8mm、高35mm φ 之圓柱狀玻璃，如圖1所示，將包含該圓柱狀玻璃10之中心軸12厚爲2〜5mm之玻璃板14切出。將切出面之兩面予以光學硏磨加工（鏡面硏磨表面處理），製作出評價用樣品。對關於相當於由坩鍋之玻璃上面1〜1 〇mm之間之部位’將光學硏磨加工面以實體顯微鏡觀察，計測玻璃板中之直徑5 0 μιη以上之泡數，將其値除以玻璃板之體積 ’作爲殘留泡數。結果如表2所示。Ba◦ suppresses the phase separation of the alkali-free glass, improves the devitrification property, and improves the chemical resistance of φ. When BaO is 13.5% by mass or less, the density of the alkali-free glass is lowered. The coefficient of thermal expansion is lowered, the Young's modulus is improved, the meltability is improved, and the B H F resistance is improved. However, if you consider the burden on the environment, it is better not to contain it. When the MgO + CaO + SrO + BaO is 16% by mass or more, the meltability of the glass is improved. When the MgO + CaO + SrO + BaO is 29.5 mass% or less, the density and thermal expansion coefficient of the alkali-free glass are lowered. According to the method for producing an alkali-free glass of the present invention as described above, -23-1377181 is the above-mentioned ceramsite, D 5 〇 is 15 to 60 μm ′′, and the ratio of particles having a particle diameter of 100 μm or more is 2.5% by volume. In the following, as a source of boron, a boron source is used in an amount of 10% by mass (in terms of β2ο3), and 10 to 100% by mass of boric anhydride (in terms of Β2〇3) is used. As a clarifying agent, at least Sn02 is used. The melting of the raw material is carried out in at least two steps of the above steps (a) and (b), and an alkali-free glass having a small amount of bubbles in the glass and having high homogeneity and flatness can be obtained. [Examples] The present invention will be specifically described by the following examples, but the present invention should not be construed as being limited by the examples. Examples 1 and 2 are experimental examples showing low-temperature meltability, Examples 3 to 5, 7 and 8 are Examples, and Example 6 is a comparative example. [Example 1] SiO2: 60% by mass, a1203: 17% by mass, B2〇3: 8% by mass, MgO: 3% by mass, ca 0 : 4% by mass, expressed as a percentage by mass based on the oxide. , S r Ο : 8 mass% of glass base material composed of alkali-free glass, 矽 sand 1 (〇5〇: 27μιη, particle size ΙΟΟμηι or more particles ratio: 0% by volume, D99 (volume occupancy in the particle size distribution) 99% of the particle diameter): 69μιη.), as a boron source, boric anhydride (1 〇〇4 0/0} ' as the aluminum source with αι203, and other raw materials to make the glass S material into the raw material, further as The clarifying agent is added to 0.5% by mass of Sn 〇 2, 0.5% by mass of SrCl 4 and -24 to 1377181 0.3% by mass of CaS04. 2H20 to the glass base material constituent raw material to form a glass raw material. In order to become a glass material of 250 g, a bottomed cylindrical pin having a height of 90 mm and an outer diameter of 70 mm is placed in a j-pot; the pan is placed in a heating furnace, and the dew point is blown from the side of the heating furnace. 'At 60 °C' air at 1 525 °C (the viscosity of the molten glass becomes 1〇2 After heating for 30 minutes at a temperature of 6 dPa · s, the mixture was stirred in a crucible for 30 minutes by a stirrer to melt the glass raw material. Thereafter, the stirring was stopped, and the mixture was allowed to stand for 60 minutes φ clock, and the crucible was melted. The glass flows out onto the carbon plate and is cooled in a slow cooling furnace. After cooling, the sample is taken out from the slow cooling furnace, and light is irradiated from the edge of the sample, and the number of unmelted cerium oxide is counted by a solid microscope. The results are shown in Table 1. The same evaluation was carried out for the melting temperature of the glass raw material to be 1550 ° C (the viscosity of the molten glass was 1025 dPa·s). The results are shown in Table 1. [Example 2] In addition to the use of strontium sand 2 (D5 〇: 39 μm, ratio of particles having a particle size of ΙΟΟμηη or more: 4.2% by volume, D99: 153 μm), and using orthoboric acid (1% by mass) as a boron source, The same evaluation was carried out as in Example 1. The results are shown in Table 1. -25 - 1377181 [Table 1] Melting temperature (°C) Viscosity of molten glass (dPa.s) Amount of unmelted sand oxide (units/kg) Example 1 Example 2 矽 sand 1 + boric anhydride 矽 sand 2+ positive boron 1525 1025 757 1230 1550 1025 188 1021 The composition of the present invention (D5〇: 15~60μπι, the ratio of particles having a particle diameter of ΙΟΟμπι or more: 2.5% by volume or less) to the combination of cerium 1 and boric anhydride, and the present invention When the composition of the cerium 2 and the orthoboric acid are different, the amount of the unmelted cerium oxide is small, and the initial dissolution can be performed at a lower temperature. Further, since the amount of unmelted cerium oxide is small, the glass having high homogeneity is high. Further, it is possible to obtain a glass having a high flatness when the sheet glass is molded. [Example 3] A glass base material composition raw material similar to that of Example 1 was further used as a clarifying agent, and 5% by mass of Sn 〇 2 was added to the glass base material constituent raw material to form a glass raw material. Step (a): A half amount of the glass raw material (corresponding to 125 g in terms of glass) was placed in a 300 cc platinum crucible, and allowed to stand in an electric furnace at 1500 ° C (the viscosity of the molten glass was 1027 dPa·s) for 30 minutes. . Temporarily take out the platinum crucible from the electric furnace, and add the remaining half amount (equivalent to 1 2 5 g in terms of glass), and then rest on the l5〇〇C (the viscosity of the molten glass becomes 1027dPa.s). The glass frit was melted in the oven for 30 minutes. -26- 1377181 Step (b): Thereafter, it was quickly transferred to an electric furnace at 1590 ° C (the viscosity of the molten glass was 102 3 dPa·s), and allowed to stand for 30 minutes. Thereafter, the mixture was transferred to an electric furnace at 730 ° C, and it took 2 hours to slowly cool the glass to 610 ° C, and further, it took about 10 hours to cool the glass to room temperature. Then, the glass in the center of the upper portion of the crucible is drilled through a cylindrical glass having a diameter of 38 mm and a height of 35 mm φ. As shown in FIG. 1, the central axis 12 including the cylindrical glass 10 is 2 to 5 mm thick. The glass plate 14 is cut out. The two sides of the cut surface were subjected to optical honing processing (mirror honing surface treatment) to prepare a sample for evaluation. For the portion corresponding to the position between 1 and 1 mm between the top of the glass of the crucible, the optically honed surface is observed by a stereoscopic microscope, and the number of bubbles of 50 Å or more in the glass plate is measured and divided. The volume of the glass plate is taken as the number of residual bubbles. The results are shown in Table 2.

除了將步驟（a)之溫度變更爲1 5 5 0°C (溶融玻璃之黏度成爲1 02 5 dPa .s溫度）以外，與例3進行了相同的評價。結果如表2所示。〔例5〕以氧化物基準之質量百分比表示下，使成爲具有Si 02 :60 質量％、a12〇3 : 17 質量％、B2〇3 : 8 質量％、MgO : 5質量％、Ca〇 : 6質量％、SrO : 4質量％之玻璃母材組成 -27- 1377181 之無鹼玻璃，矽砂1，作爲硼源以硼酸酐（100質量％)，作爲鋁源以Al2〇3、及調製其他之原料成爲玻璃母材組成原料，更進一步，作爲澄清劑.，相對於該玻璃母材組成原料，添加0.5質量％之Sn〇2，使成玻璃原料。步驟（a): 將該玻璃原料之半量（以玻璃換算相當於125 g)放入 φ 30〇cc之鉑坩鍋，在 1 500 °C (熔融玻璃之黏度成爲 1 〇2 5dPa · s之溫度）之電爐中靜置30分鐘。暫且從電爐中取出鉑坩鍋，追加剩下的另一半量（以玻璃換算相當於 125g)，再次靜置於 1500 °C (熔融玻璃之黏度成爲 102_5dPa· s之溫度）之電爐中30分鐘使玻璃原料熔融。步驟（b): 其後，迅速轉移至15 90 °C (熔融玻璃之黏度成爲 φ 102」dPa.s之溫度）之電爐，靜置30分鐘。其後，轉移至730 °C之電爐，花費2小時使玻璃緩冷卻至610 °C，更進一步約花費1 〇小時使玻璃緩冷卻至室溫。然後，與例3 同樣地進行製作了評價用樣品，求得殘留泡數。結果如表 2所示。〔例6〕準備了與例2相同的玻璃原料。 -28- 1377181 '步驟（a): 將該玻璃原料之半窠（以玻璃換算相當於l25g)放入 30 0cc之鈾坩鍋 '在丨59〇。(：（熔融玻璃之黏度成爲 l〇23dPa. s之溫度）之讓爐中靜置30分鐘。暫且從電爐將鉑坩鍋取出，追加剩下的另一半量（以玻璃換算相當於 l25g)，再次靜置於l59〇°C (溶融玻璃之黏度成爲 102.3dPa. s之溫度）之電爐中30分鐘後溶解。步驟（b ): 其後，迅速轉移至1590 °C (熔融玻璃之黏度成爲 102 3dPa · s之溫度）之電爐，靜置30分鐘。其後，轉移至73〇°C之電爐，花費2小時使玻璃緩冷卻至610°C、更進一步約花費1 0小時使玻璃緩冷卻至室溫。然後，與例3 同樣地進行製作了評價用樣品，求得殘留泡數。結果如袠 2所示。〔表2〕，驟(a) 步驟(b) 溫度差 (b)-(a) (°C) 殘留、 (個/cm3) 溫度 CC) 黏度 (dPa · s) 溫度 CC) 黏度 (dPa . s) 時間 (分）例3 1500 ίο2·7 1590 1023 30 90 60^^ 例4 1550 1025 1590 1023 30 40 215~~ 例5 1500 1025 1590 1021 15 90 160 例6 1590 1023 1590 1023 30 0 """-----^ 1235 〔例7〕 -29- 1377181 除了作爲鋁源使用了 Al( OH) 3以外’與例1同樣地進行，使成玻璃母材組成原料，更進一步作爲澄清劑，相對於該玻璃母材組成原料，添加0.5質量％之Sn〇2、〇.5 質量％之SrCl4、0.3質量％之CaS〇4 · 2H20及〇· 1質量％之CaF2，作爲玻璃原料。除了使用了以上述所得之玻璃原料以外’與例3同樣地進行，作成評價用樣品，求得殘留泡數。結果如表3所示。〔例8〕除了將步驟（a)之溫度變更爲1450 °C (熔融玻璃之黏度成爲1〇2 8dPa . s之溫度）以外，與例7進行了相同之評價。結果如表3所示。〔表3〕 % 》驟⑷ 步驟(b) 溫度差殘留泡數溫度黏度溫度黏度時間 (b)-(a) (ii/cra3) (°C) (dPa · s) (°C) (dPa · s) (分） (°C) 例7 1500 ίο2·7 1590 ίο2·3 30 90 50 例8 1475 1028 1590 1023 30 115 45 將於步驟（a)中將玻璃原料在熔融玻璃之黏度成爲超過102 4dPa · s之溫度下加熱，於步驟（b )中將熔融玻璃在熔融玻璃之黏度成爲102 4dPa . s以下之溫度下，且比前述步驟（a )中溫度高3 0 t以上之溫度下加熱過後之例3〜5’與於步驟（a)中也將玻璃原料在熔融玻璃之黏 -30- 1377181 度成爲1 02 4dPa . s以下之溫度下加熱，步驟（a)與步驟 (b)之熔融玻璃的黏度無差別之例6相比較，得知殘留泡數爲少，澄清效果爲大一事" 更進一步，玻璃母材組成原料中含有Al(OH) 3之例 7及8中得知，特別係例8，步驟（a )中將玻璃原料在低溫下溶解，就算熔融玻璃之黏度變高，也可得到良好之熔融特性，例7、8中殘留泡數爲少，且澄清效果爲大一事〔產業上之可利用性〕藉由本發明之製造方法所得到之無鹼玻璃，其玻璃中之泡爲少，均質性、平坦度爲高。又，因含有B203其耐藥品性及耐久性也極優。該無鹼玻璃，作爲液晶顯示基板用玻璃等極爲有用。尙，本說明書之全內容，係引用自於2007年10月25 φ 日申請專利之日本專利申請2007-?77802號的說明書、專利申請範圍、圖式及摘要之全內容，以作爲本發明的說明書揭示，本發明說明書係爲引用其者。【圖式簡單說明】〔圖〗〕爲表示從圓柱狀玻璃中切出樣品用之玻璃板部份之圖。【主要元件符號說明】 -31 - 1377181 10 :玻璃 1 2 :中心軸 14 :玻璃板The same evaluation as in Example 3 was carried out, except that the temperature in the step (a) was changed to 1 5 50 ° C (the viscosity of the molten glass was 1 02 5 dPa·s). The results are shown in Table 2. [Example 5] In terms of mass percentage of oxide, it is made to have Si 02 : 60% by mass, a12 〇 3 : 17% by mass, B2 〇 3 : 8% by mass, MgO: 5% by mass, Ca 〇: 6 Mass %, SrO: 4% by mass of glass base material composition -27- 1377181 of alkali-free glass, strontium sand 1, boronic acid source (100% by mass) as boron source, Al2〇3 as aluminum source, and other preparations The raw material is a raw material of the glass base material, and further, as a clarifying agent, 0.5% by mass of Sn 2 is added to the raw material of the glass base material to form a glass raw material. Step (a): Put half of the glass raw material (corresponding to 125 g in terms of glass) into a platinum crucible of φ 30 〇cc at a temperature of 1 500 ° C (the viscosity of the molten glass becomes 1 〇 2 5 dPa · s The oven was allowed to stand for 30 minutes. Temporarily take out the platinum crucible from the electric furnace, and add the remaining half amount (125 g in terms of glass), and again set it in an electric furnace at 1500 ° C (the viscosity of the molten glass is 102_5 dPa·s) for 30 minutes. The glass raw material is melted. Step (b): Thereafter, the furnace was quickly transferred to an electric furnace at 15 90 ° C (the viscosity of the molten glass was φ 102"dPa.s), and allowed to stand for 30 minutes. Thereafter, the furnace was transferred to an electric furnace at 730 ° C, and it took 2 hours to slowly cool the glass to 610 ° C, and it took about 1 hour to cool the glass to room temperature. Then, a sample for evaluation was produced in the same manner as in Example 3, and the number of residual bubbles was determined. The results are shown in Table 2. [Example 6] The same glass raw material as in Example 2 was prepared. -28- 1377181 'Step (a): Put half of the glass material (equivalent to l25g in glass) into a 30 cc uranium crucible ' at 59 〇. (: (the viscosity of the molten glass is the temperature of l〇23dPa. s) Let the furnace stand for 30 minutes. Take out the platinum crucible from the electric furnace and add the remaining half (equivalent to l25g in terms of glass). Dissolve again in an electric furnace at l59 ° C (the viscosity of the molten glass becomes 102.3 dPa·s) and dissolve for 30 minutes. Step (b): Thereafter, rapidly transfer to 1590 ° C (the viscosity of the molten glass becomes 102). The electric furnace of 3dPa · s temperature was allowed to stand for 30 minutes. Thereafter, it was transferred to an electric furnace of 73 ° C. It took 2 hours to slowly cool the glass to 610 ° C, and further took about 10 hours to cool the glass to Then, the sample for evaluation was prepared in the same manner as in Example 3, and the number of residual bubbles was determined. The results are shown in Fig. 2. [Table 2], step (a) Step (b) Temperature difference (b)-( a) (°C) Residual, (pcs/cm3) Temperature CC) Viscosity (dPa · s) Temperature CC) Viscosity (dPa. s) Time (minutes) Example 3 1500 ίο2·7 1590 1023 30 90 60^^ Example 4 1550 1025 1590 1023 30 40 215~~ Example 5 1500 1025 1590 1021 15 90 160 Example 6 1590 1023 1590 1023 30 0 """-----^ 1235 Example 7] -29- 1377181 In the same manner as in Example 1, except that Al(OH) 3 was used as the aluminum source, the glass base material was used as a raw material, and further as a clarifying agent, the raw material of the glass base material was used. 0.5% by mass of Sn 〇 2, 5.5% by mass of SrCl 4 , 0.3% by mass of CaS 〇 4 · 2H20 and 〇·1% by mass of CaF 2 were added as a glass raw material. In the same manner as in Example 3 except that the glass raw material obtained above was used, a sample for evaluation was prepared, and the number of residual bubbles was determined. The results are shown in Table 3. [Example 8] The same evaluation as in Example 7 was carried out, except that the temperature in the step (a) was changed to 1450 °C (the viscosity of the molten glass was changed to a temperature of 1〇28 dPa·s). The results are shown in Table 3. [Table 3] % 》Step (4) Step (b) Temperature difference Residual bubble number Temperature viscosity Temperature viscosity time (b)-(a) (ii/cra3) (°C) (dPa · s) (°C) (dPa · s) (minutes) (°C) Example 7 1500 ίο2·7 1590 ίο2·3 30 90 50 Example 8 1475 1028 1590 1023 30 115 45 The viscosity of the glass raw material in the molten glass will be more than 102 4dPa in step (a). · heating at a temperature of s, in step (b), the viscosity of the molten glass in the molten glass is at a temperature of 102 4 dPa·s or less, and is heated at a temperature higher than the temperature in the step (a) by more than 30 t. In the example 3 to 5' and in the step (a), the glass raw material is heated at a temperature of -30 - 1377181 degrees of the molten glass to a temperature of 1200 dPa s or less, and the melting of the steps (a) and (b) In comparison with Example 6 in which the viscosity of the glass is not different, it is known that the number of residual bubbles is small, and the clarification effect is a big one. Further, in Examples 7 and 8 in which the glass base material composition contains Al(OH) 3 , it is known that In particular, in step 8, in step (a), the glass raw material is dissolved at a low temperature, and even if the viscosity of the molten glass becomes high, good melting can be obtained. Characteristics, the number of residual bubbles in Examples 7 and 8 is small, and the clarifying effect is a big one. [Industrial Applicability] The alkali-free glass obtained by the production method of the present invention has less bubbles in the glass and is homogeneous. The flatness is high. In addition, B203 is excellent in chemical resistance and durability. This alkali-free glass is extremely useful as a glass for a liquid crystal display substrate. That is, the entire contents of the present specification are incorporated by reference to the entire contents of the specification, the patent application, the drawings and the abstract of the Japanese Patent Application No. 2007-? The description discloses that the description of the present invention is incorporated by reference. [Simple description of the drawing] [Fig.] is a view showing a portion of the glass plate for cutting a sample from the cylindrical glass. [Description of main component symbols] -31 - 1377181 10 : Glass 1 2 : Center shaft 14 : Glass plate

Claims

1377181 X. Patent Application No. 97 1 3975 7 Patent Application Revision of Chinese Patent Application Range..., * 1,- _ y . . Republic of China 9 丨焉殳焉殳 ^^ 正 1. An alkali-free glass manufacturing A method for producing an alkali-free glass obtained by melting and forming a glass raw material in which a clarifying agent is added to a raw material of a glass base material of a boron source, characterized in that the medium diameter is 15 to 60 μm and The amount of the particles having a particle diameter of 100 μm or more is 2.5% by volume or less. As the boron source, the boronic acid anhydride is contained in an amount of 10 to 100% by mass based on 100% by mass of the boron source (in terms of β2ο3). In the case of the above-mentioned clarifying agent, at least Sn02 is used, and the glass raw material is melted at least in the following two steps: (a) The glass raw material is heated at a temperature at which the viscosity of the molten glass exceeds 1 02 4 dPa · s. a step of forming molten glass; (b) after the step (a), the molten glass is made to have a viscosity of the molten glass of not more than 1 4 dPa·s and being higher than the temperature in the step (a) by 30 ° C or more. It The step of heating the temperature to defoam the bubbles in the molten glass. 2. The method for producing an alkali-free glass according to the first aspect of the invention, wherein the glass base material composition material contains aluminum or an alkaline earth metal hydroxide. 3. The method for producing an alkali-free glass according to claim 1 or 2, wherein the mass percentage based on the oxide is expressed as 'the composition of the 1371181 U 1 glass base material is prepared into a glass base material as described below. (1) The alkali-free glass, tin is added to the glass base material composition material in terms of Sn02. • 0. ο 1 to 2 mass% of the glass material, Si02: 50 to 66% by mass, a1203: 1〇.5~ 22 quality. /. , B2〇3 : 5~12% by mass, MgO: 〇~8 mass. /〇, CaO: 〇~14.5 mass%, SrO: 0~24 mass%, BaO: 0-13.5 mass%, MgO + CaO + Sr〇 + 83〇: 9 to 29.5 mass% . . . (1). #4. The method for producing an alkali-free glass according to the first or second aspect of the patent application, wherein the glass base material is prepared as a raw material, and the glass base material is prepared as follows (2) The alkali-free glass is added to the glass base material composition material in an amount of S η Ο 2 〇〇 1 to 2% by mass to form a glass raw material, Si02: 58 to 66% by mass, Α12〇3: 15 to 22% by mass %, Β2〇3: 5~1 2% by mass, MgO: 0 to 8% by mass, CaO: 0 to 9% by mass, SrO: 3 to 12.5% by mass, BaO: 0 to 2% by mass, MgO + CaO + SrO + BaO : _ 9 ~ 1 8 mass % . . . ( 2 ). 5. The method for producing an alkali-free glass according to the first or second aspect of the patent application, wherein the raw material of the glass base material is prepared into a glass base material as described below by mass percentage based on the oxide ( 3) the alkali-free glass, the tin is added to the glass base material composition material in an amount of 0.01 to 2 mass% in terms of Sn02 to form a glass raw material 'Si02 * 50 to 61.5% by mass, AI2O3: 1 〇 · 5 to 18% by mass, B2O3: 7 to 10% by mass, MgO: 2 to 5 mass%, CaO: 0 to 14_5 mass%, SrO: 〇~24 mass. /. , BaO: 0 ~ 13.5 mass %, MgO + CaO + SrO + I37Z181 year and month correction replacement page η κ ____ Ba〇 : 16~29.5 mass % . . · (3). 6. The method for producing an alkali-free glass according to the first or second aspect of the invention, wherein the raw material of the glass base material is further added with a chloride content of 3% by mass or less in terms of C1, and converted in S03. The total amount of one or more selected from the group consisting of a sulfate of 3% by mass or less and a fluoride of 3% by mass or less in terms of F is 0.01 to 5 mass%, and is used as a glass raw material. In addition, the method of producing the alkali-free glass of the above-mentioned glass base material is further added with 15 to 300% by mass of nitrate and alkali-free glass in an amount of 0.01 to 10% by mass in terms of N03. Glass swarf is used as a glass raw material. -3-