JP2724709B

• Main Authors: KANBA MOTOI, MATSUO HITOSHI
• Format: Patent
• Language: English
• Published: 09.03.1998
• Edition: 6
• Subjects: CHEMICAL COMPOSITION OF GLASSES, GLAZES, OR VITREOUSENAMELS; CHEMISTRY; COMPOSITIONS BASED THEREON; GLASS; JOINING GLASS TO GLASS OR OTHER MATERIALS; MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVINGCARBON-TO-CARBON UNSATURATED BONDS; METALLURGY; MINERAL OR SLAG WOOL; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICS; ORGANIC MACROMOLECULAR COMPOUNDS; PHYSICS; SURFACE TREATMENT OF FIBRES OR FILAMENTS MADE FROM GLASS,MINERALS OR SLAGS; SURFACE TREATMENT OF GLASS; THEIR PREPARATION OR CHEMICAL WORKING-UP

PURPOSE:To improve transparency and strength of a clad layer and to reduce the refractive index thereof by using a specified F-contg. polymer for the clad material. CONSTITUTION:An F-contg. polymer (A) having a ring structure in the principal chain is used for the clad material. The ring of the polymer (A) is preferred to contain F and an ether linkage and is pref. a 4-7 membered ring. Further, the polymer (A) is pref. a perfluoro polymer such as those expressed by the formula wherein l is 0-5; m is 0-4; n is 0-1; l+m+n is 1-6; R is F or CF3. The clad layer is formed by coating a core consisting of quartz glass or optical glass with a soln. of the polymer (A) and removing the solvent or by extruding in molten state.