Patterned coated abrasive for fine surface finishing
AssigneeNorton Company
InventorsSitaramaiah Ravipati, Eugene Zador, Wesley R. Kaczmarek, Ernest A. Coleman, David Rostoker
Life of this patent
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Abstract
Coated abrasive material for fine finishing applications including second fining ophthalmic application, having patterned surface coating of abrasive grains dispersed in radiation-cured adhesive binder. The patterned surface coating is defined by a plurality of formations of such abrasive/binder each having an inner bottom edge defining an area devoid of coated abrasive, a top edge defining a somewhat larger area devoid of coated abrasive and an inner wall connecting the top and bottom edges.
Claims45
A coated abrasive material suitable for use in lapping operations comprising:
- (a) a flexible and dimensionally stable backing member:
- (b) an abrasive grain containing material adhered to one surface of the backing member, said material being configured in a plurality of elongated discrete three-dimensional formations interspersed with areas devoid of abrasive material such that the abrasive grain containing material forms a discontinuous surface opposite the backing member.
Coated abrasive material suitable for use in fine finishing applications comprising:
- (a) a backing member;
- and
- (b) a raised pattern on said backing member defined by a plurality of contiguous formations of a coated abrasive each said formation having a top edge and an inner bottom edge which define areas having no abrasive material and an inner wall of abrasive material connecting together said top and bottom edge, said abrasive coating comprising particles of abrasive grain dispersed in a radiation cured binder system, a coating of a suitable silane coupling agent being provided on said abrasive grain particles, said binder system binding said abrasive particles together and to the said backing member and comprising in combination as its major components a radiation cured mixture comprising a diacrylated epoxy oligomer of the bisphenol-a type, trimethylol propane triacrylate, hexane diol diacrylate, and N-vinyl-2-pyrrolidone.
A process for the manufacture of a coated abrasive material suitable for use in lapping operations comprising:
- (a) providing a dispersion of abrasive grain in a curable binder, said dispersion having non-Newtonian properties;
- (b) depositing said dispersion on one side of a dimensionally stable backing member in a pattern of three-dimensional coated abrasive formations and a plurality of areas devoid of abrasive material;
- and
- (c) curing said binder to freeze said dispersion in said pattern.
Process for the manufacture of coated abrasive material suitable for use in fine finishing applications comprising the following steps:
- (a) first providing particles of precision graded, high purity abrasive grain in a size range of from about 0.2 microns to about 35 microns;
- (b) applying to said abrasive grain particles a solution comprising a silane coupling agent suitable for coupling abrasive grain to an organic binder dissolved in a water:alcohol solution;
- (c) drying said silane coated abrasive grain particles and breaking up any agglomerates formed to provide suitable sized silane treated abrasive grain particles;
- (d) admixing said silane treated abrasive grain particles with and dispersing said particles in a binder composition comprising as the essential components a diacrylated epoxy resin oligomer of the bisphenol-A type, a monomer of trimethylolpropane triacrylate, a monomer of hexanediol diacrylate, and vinyl pyrrolidone whereby to form a highly viscous, non-Newtonian liquid dispersion;
- (e) providing a backing member of polyethylene terapthalate;
- (f) applying said dispersion of binder and abrasive grain to said backing member with a rotogravure roll whereby to provide a pattern thereon defined by a plurality of contiguous coated abrasive formations each defined by a bottom and top edge defining areas devoid of coated abrasive and an inner wall connecting the two edges together;
- and
- (g) curing the binder in said dispersion by UV light.
Process for increasing adhesion between abrasive grains and a binder wherein the abrasive grains are dispersed in a liquid binder composition comprising a combination of radiation curable monomers having mono- and multi- acrylate functionality, said process comprising:
- (a) admixing a silane coupling agent with an equal amount by weight of water;
- (b) allowing said mixture to hydrolyze;
- (c) mixing a desired amount of abrasive grain with said hydrolyzed silane coupling agent;
- (d) allowing said mixture of grain and coupling agent to stand for several hours for conditioning;
- and
- (e) drying said silane treated grains at a temperature above 100.degree. C. for several hours.
Dependencies are inferred from the claim text.