CLASSIFYING METHOD OF HOLLOW SILICA POWDER AND PRODUCTION OF MULTILAYER SUBSTRATE HAVING LOW DIELECTRIC CONSTANT

• Main Authors: YOKOUCHI KISHIO, AOKI SHIGENORI, KAMEZAKI HIROSHI
• Format: Patent
• Language: English
• Published: 05.04.1994
• Edition: 5
• Subjects: CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; MAGNETIC OR ELECTROSTATIC SEPARATION OF SOLID MATERIALS FROM SOLIDMATERIALS OR FLUIDS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS; PERFORMING OPERATIONS; PRINTED CIRCUITS; SEPARATING SOLID MATERIALS USING LIQUIDS OR USING PNEUMATICTABLES OR JIGS; SEPARATION BY HIGH-VOLTAGE ELECTRIC FIELDS; SEPARATION OF SOLID MATERIALS USING LIQUIDS OR USING PNEUMATICTABLES OR JIGS; TRANSPORTING

PURPOSE:To classify hollow silica powder particles and to remove hollow silica powder of large particle size by adding stress to the hollow silica powder to selectively break particles of larger particle size and dispersing the powder in a soln. to recover only particles floating on the soln. CONSTITUTION:Since most of hollow silica powder particles having large particle size has high foaming rate, these particles have small wall thickness compared to hollow silica powder having a small particle size. Therefore, hollow silica powder having a small particle size is obtd. by adding stress to the powder to break hollow silica particles of larger particle size, dispersing the powder in water, and recovering only particles floating on the water. By using the recovered powder, a substrate having low dielectric const. and small surface roughness can be obtd.