公开(公告)号：EP1074516A1

公开(公告)日：2001-02-07

申请号：EP00306267.6

申请日：2000-07-24

Applicant: LUCENT TECHNOLOGIES INC.

Inventor： Alonzo, John C. ,  Bhandarkar, Suhas Dattatreya ,  Bohrer, Michael Philip ,  Johnson, David Wilfred Jr.

IPC: C03B8/02 ,  C03B19/12

CPC classification number: C01B33/1417 ,  C03C1/006

Abstract: Silica sols exhibiting desirable yield-dilatancy are fabricated. A mixture comprising silica, water, and a pH-adjusting agent is provided, and the mixture is shear-mixed. The desirable properties of the resultant sol are attained by using a concentration of pH-adjusting agent that provides a viscosity within a particular range during shear mixing. The requisite pH range, however, changes depending on the properties of the silica mixture. A discovered technique for determining this changing pH range is by selecting the pH based on the silica surface area per unit volume of the mixture.

Abstract translation: 制造显示出期望的屈服 - 膨胀的二氧化硅溶胶。 提供包含二氧化硅，水和pH调节剂的混合物，并将混合物剪切混合。 通过使用在剪切混合期间提供特定范围内的粘度的pH调节剂的浓度来获得所得溶胶的所需性质。 然而，所需的pH范围根据二氧化硅混合物的性质而变化。 用于确定该变化的pH范围的发现技术是通过基于混合物的每单位体积的二氧化硅表面积选择pH。

公开(公告)号：EP0974557B1

公开(公告)日：2002-10-02

申请号：EP99305529.2

申请日：1999-07-12

Applicant: LUCENT TECHNOLOGIES INC.

Inventor： Bhandarkar, Suhas Dattatreya ,  Chandross, Edwin Arthur ,  Putvinski, Thomas Michael

IPC: C03C1/00 ,  C01B33/16

CPC classification number: C01B33/1417 ,  C03B19/12 ,  C03C1/006 ,  C03C2203/30

公开(公告)号：EP0974557A1

公开(公告)日：2000-01-26

申请号：EP99305529.2

申请日：1999-07-12

Applicant: LUCENT TECHNOLOGIES INC.

Inventor： Bhandarkar, Suhas Dattatreya ,  Chandross, Edwin Arthur ,  Putvinski, Thomas Michael

IPC: C03C1/00 ,  C01B33/16

CPC classification number: C01B33/1417 ,  C03B19/12 ,  C03C1/006 ,  C03C2203/30

Abstract: A silica body useful for forming an optical fiber preform exhibits an ultimate strength of at least 20 MPa at 10 wt.% water loss. The body attains this strength, it is believed, by precipitation of silica at the contact sites of adjacent silica particles, thereby forming neck regions. The resultant network provides the strength to the gel body, such that the body is capable of being dried under more severe conditions than a gel body formed by previous sol-gel methods and is also more robust toward handling. The controlled precipitation is attained by inducing gelation and initiating drying at a pH of about 10.5 or higher, at which silica remains highly soluble. By gelling and drying at this pH level, the solubilized silica appears to precipitate in a controlled manner at the point of contact of adjacent silica particles, since such sites are the minimum free energy sites for precipitation.

Abstract translation: 用于形成光纤预制件的二氧化硅体在10重量％的水分损失下表现出至少20MPa的极限强度。 相信二氧化硅在相邻的二氧化硅颗粒的接触部位析出，从而形成颈部，达到这个强度。 所得网络为凝胶体提供强度，使得身体能够在比由先前的溶胶 - 凝胶法形成的凝胶体更恶劣的条件下干燥，并且对于处理也更加坚固。 通过诱导凝胶化并在约10.5或更高的pH下开始干燥来实现受控沉淀，其中二氧化硅保持高度可溶性。 通过在该pH水平下胶凝和干燥，溶解的二氧化硅似乎在相邻二氧化硅颗粒的接触点处以受控的方式沉淀，因为这些位点是用于沉淀的最小自由能位点。