Method of producing polishing sheet

Abstract

A polishing sheet, having polishing particles fixed to a base sheet in a single-layer formation by an adhesive agent so as to be mutually separated in the direction of their plane and having cutting edges exposed and arranged to be coplanar, is produced by forming on a provisional base sheet a film of a provisional adhesive agent of a thickness smaller than the average diameter of the polishing particles, dispersing the polishing particles onto the film of the provisional adhesive agent so as to contact the provisional base sheet, pressing the base sheet covered with the adhesive agent onto the polishing particles with the adhesive agent facing towards the polishing particles, hardening the pressed adhesive agent, and removing the provisional base sheet and the film of the provisional adhesive agent. The polishing particles are charged in a same polarity when dispersed.

1 . A polishing sheet comprising a base sheet and polishing particles fixed to the base sheet in a single-layer formation by an adhesive agent, edge parts of said polishing particles being arranged to be coplanar and being distributed separatedly. 
     
     
         2 . A method of producing a polishing sheet characterized as having polishing particles fixed to a base sheet in a single-layer formation by an adhesive agent, edge parts of said polishing particles being arranged to be coplanar and being distributed separatedly, said method comprising:
 a first step of forming on a provisional base sheet a film of a provisional adhesive agent with thickness less than the average particle diameter of the polishing particles;   a second step of distributing the polishing particles on the film of provisional adhesive agent so as to contact the provisional base sheet;   a third step of pressing a base sheet covered with an adhesive agent such that said adhesive agent faces the polishing particles;   a fourth step of hardening the adhesive agent that has been compressed; and   a fifth step of peeling off said provisional base sheet after said adhesive agent has been hardened and further removing said film of provisional adhesive agent.   
     
     
         3 . The method of producing a polishing sheet described in  claim 2  characterized wherein the thickness of said provisional adhesive agent is 1/10 or more and ⅔ of less of the average diameter of said polishing particles. 
     
     
         4 . The method of producing a polishing sheet described in  claim 2  or  3  characterized wherein the polishing particles are charged in a same polarity. 
     
     
         5 . The method of producing a polishing sheet described in  claim 4  characterized wherein the polishing particles charged in said same polarity are dispersed onto aid film of said provisional adhesive agent on said provisional base sheet while maintaining said provisional base sheet at a ground potential such that said polishing particles are mutually separated and come into contact with said provisional base sheet. 
     
     
         6 . The method of producing a polishing sheet described in  claim 5  characterized wherein the polishing particles are charged in the same polarity at a charging potential of 1-50 kV. 
     
     
         7 . The method of producing a polishing sheet described in any of  claims 2 - 6  characterized wherein the film of said provisional adhesive agent formed on the provisional base sheet comprises a water-soluble or organic acid water-soluble film. 
     
     
         8 . The method of producing a polishing sheet described in any of  claim 7  characterized wherein the water-soluble or organic acid water-soluble film comprises polysaccharides, pastes, starches, chitin or chitosan. 
     
     
         9 . The method of producing a polishing sheet described in any of  claim 8  characterized wherein the water-soluble film comprises glycogen, cellulose, dextran, dextrine, polyvinyl alcohol, or starches generated from plants. 
     
     
         10 . The method of producing a polishing sheet described in any of  claims 4 - 6  further comprising the step of maintaining an inner wall of a dispersion device for dispersing said polishing particles charged in said same polarity onto said film of said provisional adhesive agent on said provisional base sheet in the same polarity as the polarity of said polishing particles.