Method for manufacturing a flexible abrasive disc, and a flexible abrasive disc

Abstract

The present invention relates to a method for manufacturing a flexible abrasive disc, and to such an abrasive disc. The abrasive disc comprises a backing with an upper side and a lower side. The upper side has an abrasive agent coating for forming a surface layer. In order to form a surface layer as specifically patterned as possible, the backing of each abrasive disc is coated separately. In this manufacturing method, the abrasive agent coating on the upper side of the backing is embossed with an embossing mold specially structured and to be pressed against the backing.

1 . A method for manufacturing a flexible abrasive disc, which abrasive disc comprises a backing with an upper side and a lower side, whereby the backing has in its periphery a side edge binding together the upper side and the lower side, the upper side being provided with an abrasive agent coating for forming a surface layer, wherein
 the coating of the backing of each abrasive disc is done separately, whereby   the backing is arranged in a separate position on a press piston, where   the abrasive agent coating is applied to the upper side of the backing and formed as a patterned surface layer by   bringing a press piston, which is positioned opposite the backing and has a structured embossing mold oriented towards the upper side of the backing, towards the backing to   emboss the surface layer with reciprocal pressing together of the press pistons, after which   the abrasive agent coating is cured for final forming of the surface layer, and   the molds of the finished abrasive disc are removed.   
   
   
       2 . A method according to  claim 1 , whereby the backing is arranged on a separate press piston. 
   
   
       3 . A method according to  claim 1 , whereby the backing is arranged in a separate press chamber in a press piston. 
   
   
       4 . A method according to  claim 1 , whereby the backing is shaped to have a substantially spherical upper side. 
   
   
       5 . A method according to  claim 4 , whereby the backing is shaped to be substantially of even thickness with a substantially spherical upper side and lower side, and the surface of the press piston is shaped to correspond to the bending radius of the lower side of the backing. 
   
   
       6 . A method according to  claim 1 , whereby the abrasive agent coating is applied stepwise with alternating application of at least glue and sand onto the upper side of the backing to form the surface layer. 
   
   
       7 . A method according to  claim 1 , whereby the abrasive agent coating is sprayed to the upper side of the backing in the form of a slurry which comprises at least abrasive agent and binding agent to form the surface layer. 
   
   
       8 . A method according to  claim 1 , whereby the backing and the embossing mold brought against the surface layer are kept together after the pressing together by the abrasive agent coating applied to the upper surface in the pressing together, and the abrasive agent coating is cured after the backing with the abrasive agent coating applied to the upper side has been removed from a press chamber formed by the press pistons. 
   
   
       9 . A method according to  claim 1 , whereby the backing is manufactured by injection-molding in a separate mold. 
   
   
       10 . A method according to  claim 9 , whereby the backing is manufactured by injection-molding in a separate mold in which the upper side of the backing is subsequently coated. 
   
   
       11 . A method according to  claim 1 , whereby the backing is manufactured by stretch molding to be subsequently arranged on a press piston on which its upper side is then coated. 
   
   
       12 . A method according to  claim 11 , whereby the backing is cut off a stretch-molded material strip. 
   
   
       13 . A method according to  claim 11 , whereby the backing is subjected to stretch molding when cut off a material strip. 
   
   
       14 . A method according to  claim 1 , whereby the upper and lower press pistons are pressed together under vacuum. 
   
   
       15 . A method according to  claim 1 , whereby the embossing mold is formed of a polymer material to comprise a disposable element. 
   
   
       16 . A flexible abrasive disc comprising a backing with an upper side and a lower side, whereby the backing has in its periphery a side edge to bind together the upper side and the lower side, as well as an abrasive agent coating arranged on the upper side of the backing for forming a surface layer, whereby
 the surface layer has a substantially spherical surface with an embossed structure.   
   
   
       17 . A flexible abrasive disc according to  claim 16 , whereby the surface layer is of a substantially convex shape. 
   
   
       18 . A flexible abrasive disc according to  claim 16 , whereby the surface layer is of a substantially concave shape. 
   
   
       19 . A flexible abrasive disc according to  claim 16 , whereby the backing has a structure of substantially even thickness, and its lower side and upper side are substantially parallel and the upper side is provided with an abrasive agent coating to form a surface layer which is substantially of the shape of a spherical segment. 
   
   
       20 . A flexible abrasive disc according to  claim 19 , whereby the upper side and the lower side of the backing have different bending radii. 
   
   
       21 . A flexible abrasive disc according to  claim 20 , whereby the lower side of the backing is substantially planar. 
   
   
       22 . A flexible abrasive disc according to  claim 16 , whereby the backing comprises a polymer material. 
   
   
       23 . A flexible abrasive disc according to  claim 16 , whereby the side edge of the backing has fastening elements that are arranged to keep, like a lid, the finished abrasive disc fastened when the abrasive disc is, in use, arranged on the fastening plate of an abrasive head. 
   
   
       24 . A flexible abrasive disc according to  claim 23 , whereby the fastening elements comprise an edge drawn upwards. 
   
   
       25 . A flexible abrasive disc according to  claim 23 , whereby the fastening elements comprise hooks drawn upwards. 
   
   
       26 . A flexible abrasive disc according to  claim 16 , whereby the embossed structure of the surface layer comprises a non-linear and non-interferential pattern.