Injection moldable plastic laps

Claim 2

A lap for holding an abrasive pad in the manufacture of ophthalmic lens surfaces comprising a body having front and rear sides, a curved front surface formed on said front side and a skeletal rib structure comprising a plurality of interconnected ribs projecting from said rear side to form a plurality of voids in said rear side, said skeletal rib structure spaced radially inwardly from two diametrically opposite portions of an outer circumference of said rear side and projecting rearwardly farther than said portions of said outer circumference to form a pair of side notches between said skeletal rib structure and said portions of said outer circumference, said body being of one-piece injection-molded construction of a reinforced polymer, said polymer having chemical resistance to organic solvents and sufficient rigidity, strength, and thermal resistance for repeated use as a lapping tool.

Claim 3

A lap according to claim 1, wherein said rear side comprises an annular outer peripheral rim extending along at least a portion of an outer circumference of said rear side, and a recessed surface disposed radially inwardly of said rim and recessed relative to said rim in a direction toward said front surface, said skeletal rib structure projecting rearwardly from said recessed surface.

Claim 4

A lap according to claim 2, wherein said rim comprises an annular ridge having a rearwardly facing annular surface.

Claim 5

A lap according to claim 2, wherein said ribs which are recessed radially inwardly relative to portions of said ridge to define two side notches comprise first ribs, said rib structure including additional ribs extending between said first ribs.

Claim 6

A lap according to claim 4, wherein said additional ribs include parallel second ribs defining a central generally rectangular aperture.

Claim 7

A lap according to claim 5, wherein said additional ribs include at least two third ribs extending between said first ribs and said ridge.

Claim 8

A lap according to claim 2, wherein none of said ribs has a cross-sectional thickness greater than 0.50 in.

Claim 9

A lap according to claim 1, wherein none of said ribs has a cross-sectional thickness greater than 0.50 in.

Claim 10

A lap according to claim 8, wherein a maximum thickness between said front surface and said recessed surface is 0.05 in.

Claim 11

A lap according to claim 9, wherein said maximum thickness is 0.35 in.

Claim 12

A lap according to claim 1, wherein none of said ribs has a cross-sectional thickness greater than 0.350.

Claim 13

A lap according to claim 1, wherein each said ribs has a cross-sectional thickness in the range of 0.10 to 0.35 in.

Claim 14

A lap according to claim 1, with the polymer and filler material in the combination of 20 to 45% filler and 80 to 55% polymer.

Claim 15

A lap according to claim 1, where the filler is a mineral material.

Claim 16

A lap according to claim 1, where the filler is a combination of 100% to 25% mineral and 0 to 75% glass.

Claim 17

A lap according to claim 15, wherein the filler includes short-fiber glass having a particle size of from about 0.006 to about 0.14 inch in length.

Claim 18

A lap according to claim 15, wherein the filler includes longer fiber glass having a particle size of from about 0.1 to about 0.3 inch in length.

Claim 19

A lap according to claim 1, wherein the polymer is a crystalline polymer.

Claim 20

A lap according to claim 18, where the polymer is a polyester.

Claim 21

A lap according to claim 19, where the polymer is polybutylene terephthalate.

Claim 22

A lap according to claim 19, where the polymer is polyethylene terephthalate.

Claim 23

A lap according to claim 18, where the polymer is a polyacetal.

Claim 24

A lap according to claim 22, where the polymer is polyoxymethylene homo- or co-polymer.

Claim 25

A lap according to claim 18, where the polymer is a polyimide.

Claim 26

A lap according to claim 18, where the polymer is a polyimide.

Claim 27

A lap according to claim 18, where the polymer is a polyphenylene sulfide.

Claim 28

A lap according to claim 1, wherein said reinforcement comprises a mineral reinforcement.

Claim 29

A lap according to claim 1, wherein said reinforcement comprises a fiber reinforcement.

Claim 30

A lap according to claim 1, wherein said reinforcement comprises a mineral reinforcement and a fiber reinforcement.

Claim 31

A lap for holding an abrasive pad in the manufacture of ophthalmic lens surfaces comprising a body having front and rear sides, a curved front surface formed on said front side and a skeletal rib structure comprising a plurality of interconnected ribs projecting from said rear side to form a plurality of voids in said rear side, said skeletal rib structure spaced radially inwardly from two diametrically opposite portions of an outer circumference of said rear side and projecting rearwardly farther than said portions of said outer circumference to form a pair of side notches between said skeletal rib structure and said portions of said outer circumference, said body being of one-piece injection-molded construction of a reinforced polymer, said polymer having chemical resistance to organic solvents and sufficient rigidity, strength, and thermal resistance for repeated use as a lapping tool, wherein the amount of reinforcement is sufficient to result in said body being substantially free of warpage after said injection molding, and wherein said front surface and said ribs have a thickness permitting cooling at a rate rapid enough to allow said body to be produced by high speed injection-molding.

Claim 32

A lap for holding an abrasive pad in the manufacture of ophthalmic lens surfaces comprising a body having front and rear sides, a curved front surface formed on said front side and a skeletal rib structure comprising a plurality of interconnected ribs projecting from said rear side to form a plurality of voids in said rear side, said skeletal rib structure spaced radially inwardly from two diametrically opposite portions of an outer circumference of said rear side and projecting rearwardly farther than said portions of said outer circumference to form a pair of side notches between said skeletal rib structure and said portions of said outer circumference, said body being of one-piece injection-molded construction of a reinforced polymer, said polymer having chemical resistance to organic solvents and sufficient rigidity, strength, and thermal resistance for repeated use as a lapping tool, wherein the amount of reinforcement is sufficient to result in said body being substantially free of warpage after said injection molding, and wherein said front surface and said ribs have a thickness permitting cooling at a rate rapid enough to allow said body to be produced by high speed injection-molding.

Claim 33

A lap according to claim 30, wherein the polymer is a crystalline polymer.

Claim 34

A lap according to claim 27, wherein said reinforcement comprises a mineral reinforcement.

Claim 35

A lap according to claim 27, wherein said reinforcement comprises a fiber reinforcement.

Claim 36

A lap according to claim 27, wherein said reinforcement comprises a mineral reinforcement and a fiber reinforcement.