Production tool for an abrasive article and a method of making same

A production tool for manufacturing abrasive articles made according to the steps of:

• (1) providing a production tool master having a major surface extending within a first imaginary plane, and determining angles corresponding to facing right and left planar surfaces of adjacent three-dimensional shapes and wherein each of said angles has a value as measured between its planar surface and a plane which extends in a normal direction to said major surface and contains an edge of said planar surface in contact with said major surface, by the following substeps:
• (i) selecting an angle value between, but not including 0.degree. and 90.degree. to establish a first right half angle of a first right planar surface of a first right-side three-dimensional shape with a random number generating means capable of randomly selecting an angle value between, but not including, 0.degree. and 90.degree.;
• (ii) selecting an angle value between, but not including, 0.degree. and 90.degree. with said random number generating means to establish a first left half angle for a first left planar surface of a first left-side three-dimensional shape facing said first right planar surface of said first right-side three-dimensional shape;
• (iii) proceeding along a first direction extending in said first imaginary plane to a second left planar surface of a second left-side three-dimensional shape located adjacent said first left-side three-dimensional shape and using said random number generating means to select a value between, but not including, 0.degree. and 90.degree. to establish a second left planar angle for said second left planar surface;
• (iv) using said random number generating means to select a value between, but not including, 0.degree. and 90.degree. for a second right planar surface of a second right-side three-dimensional shape facing said second left planar surface;
• (v) proceeding along said first direction to a third right-side three-dimensional shape located adjacent said second right-side three-dimensional shape;
• (vi) repeating said substeps (i), (ii), (iii), (iv), and (v), in that sequence, at least once;
• (2) repeating step (1) except that the angles are determined for left and right planar surfaces of adjacent three-dimensional shapes deployed in two adjacent rows in a second direction extending within said first imaginary plane, wherein said first and second directions intersect;
• (3) using means to determine, for a given width of said major surface of said master, locations of grooves required to be cut by a cutting means to form a series of intersecting grooves defining a plurality of precise three-dimensional shapes having said angles calculated by steps (1) and (2);
• (4) providing a cutting means to cut grooves in said major surface of said master in correspondence to said angles calculated by steps (1) and (2) and said groove locations determined by step (3) to form a series of intersecting grooves which define a plurality of precise three-dimensional shapes upraised from said major surface, each of said precise shapes being defined by a distinct and discernible boundary including specific dimensions, wherein not all of said three-dimensional shapes are identical;
• (5) applying a polymeric resin on said major surface of said master in a manner effective to flow into and conform to said three-dimensional shapes;
• (6) solidifying said polymeric resin into a substantially planar sheet;
• and
• (7) removing said polymeric resin from said major surface of said master to form said production tool, the production tool comprising at least first and second cavities formed on a major surface thereof, each cavity having a precise shape defined by a distinct and discernable boundary which includes specific dimensions.