Process for manufacturing inorganic article, inorganic article, and circuit substrate

Abstract

A process for manufacturing an inorganic material-based article comprising the steps of (1) forming a sol solution mainly composed of an inorganic component, (2) producing inorganic material-based gel fine fibers by extruding the resulting sol solution from a nozzle, and at the same time, applying an electrical field to the extruded sol solution to thin the extruded sol solution, and then, collecting inorganic material-based gel fine fibers on a support, (3) drying the collected inorganic material-based gel fine fibers to produce inorganic material-based article containing inorganic material-based dried gel fine fibers, and then, (4) sintering the inorganic material-based article containing inorganic material-based dried gel fine fibers to produce inorganic material-based article containing inorganic material-based sintered fine fibers.

1 - 6 . (canceled).  
     
     
         7 . An inorganic material-based article comprising inorganic material-based ultra-fine long fibers having an average fiber diameter of 2 μm or less, and composed mainly of an inorganic component.  
     
     
         8 . The inorganic material-based article according to  claim 7 , wherein contacting surfaces of the inorganic material-based ultra-fine long fibers are bonded to each other not via an adhesive.  
     
     
         9 . The inorganic material-based article according to  claim 7 , wherein a CV value of the inorganic material-based ultra-fine long fiber in the inorganic material-based article is 0.8 or less.  
     
     
         10 . A substrate for a circuit board, comprising a fiber sheet containing inorganic material-based ultra-fine fibers having an average fiber diameter of 2 μm or less, and composed mainly of an inorganic component.  
     
     
         11 . The substrate for a circuit board according to  claim 10 , wherein a silica component contained in the inorganic material-based ultra-fine fiber is 50 mass % or more.  
     
     
         12 . The substrate for a circuit board according to  claim 10 , wherein the fiber sheet is a nonwoven fabric.  
     
     
         13 . The substrate for a circuit board according to  claim 10 , wherein the fiber sheet consists essentially of the inorganic material-based ultra-fine fibers.  
     
     
         14 . The substrate for a circuit board according to  claim 10 , wherein the inorganic material-based ultra-fine fibers consist essentially of long fibers.  
     
     
         15 . The substrate for a circuit board according to  claim 10 , wherein a thickness of the substrate is 80 μm or less.  
     
     
         16 . A circuit board containing the substrate according to  claim 10.