Patent EA-005037-B1 (EA)
Title: Filtering material and process for making thereof
Inventor: SANDUYA MOHAN L
IPC: B01D39/18
Filed: 2001-04-30
Abstract: 1. A coating composition for the chemical grafting of an oil, fuel, coolant or air filter material, the composition comprises: about 20-40% by weight of a monomer, about 20-40 % by weight of isopropyl alcohol, about 20-40 % by weight of deionized, distilled or otherwise pure water, about 4-15 % by weight of an ester, about less than 4% by weight of a catalyst, and about less than1% by weight of a graft initiator. 2. The composition according to claim 1, which further comprises about less than 0.5 % by weight of a prepolymer. 3. The composition according to claim 2, wherein the prepolymer is a polyacrylamide polymer. 4. The composition according to claim 1, wherein the monomer is 2-acrylamido-2-methylpropanesulfonic acid sodium salt, 50% aqueous solution. 5. The composition according to claim 1, wherein the ester is a monomeric methacrylate ester. 6. The composition according to claim 1, wherein the ester is 2-hydroxyethyl methacrylate. 7. The composition according to claim 1, wherein the catalyst is at least one selected from the group consisting of hydrogen peroxide, urea peroxide, ammonium persulfate, potassium persulfate, sodium metabisulfate and mixtures thereof. 8. The composition according to claim 2, which further comprises about less than 0.5% by weight of a bactericide. 9. The composition according to claim 8, wherein the bacteriacide is a carbamate. 10. An oil, fuel, coolant or air filter comprising a filter material and a composition which chemically grafts to the filter material, wherein the filter material is at least one selected from the group consisting of cotton, paper-based materials, synthetic materials and combinations thereof, and wherein the composition comprises: about 20-40% by weight of a monomer, about 20-40 % by weight of isopropyl alcohol, about 20-40 % by weight of deionized, distilled or otherwise pure water, about 4-15 % by weight of an ester, about less than 4% by weight of a catalyst, and about less than1% by weight of a graft initiator. 11. A process for making an oil, fuel, coolant or air filter comprising the steps of: a. making a composition to chemically graft to a filter substrate, at which mixing about 20-40 % by weight of deionized, distilled or otherwise pure water, about 20-40% by weight of a monomer, about 20-40 % by weight of isopropyl alcohol, about less than 4% by weight of a peroxide-based catalyst and about less than1% by weight of a graft initiator; b. chemically grafting the composition to-the filter substrate. 12. The process according to claim 11 which further comprises the addition of about less than 0.5 % by weight of a prepolymer before mixing in the monomer. 13. The process according to claim 12, wherein the prepolymer is a polyacrylamide polymer mixed with water at temperature between about 60-100 degree C. 14. The process according to claim 12, wherein the polyacrylamide polymer is mixed with water at temperature between about 60-100 degree C and then is mixed with a bactericide, prior to mixing with any other ingredients. 15. The process according to claim 11, wherein the chemically grafting step comprises: chemically grafting the composition to the filter substrate by immersing the filter substrate in the composition. 16. The process according to claim 15, wherein the chemically grafting step further comprises: squeezing the filter substrate to remove excess composition. 17. The process according to claim 11, wherein the chemically grafting step comprises: chemically grafting the composition to the filter substrate by immersing the filter substrate in the composition, and curing the filter substrate at about 200-300 degree F.