发明人：
RILEY, MICHAEL, D. | INMAN, VICTOR, L. | ATHEY, ROBERT, D., JR.
摘要：
A filter (3) and method for applying differential levels of active ingredient materials to specific areas of filters, such as the filter paper used to make disposable vacuum cleaner bags (3), so as to cause the effluent (8) such as air which has passed through such filters (3) to sustainably act as a dispersing agent for such filter-impregnated active ingredients as may condition the effluent (8) which has passed through the filter (3) in ways that are desirable to the user of the filter (3). The active ingredients are unevenly distributed on the filter substrate (7) in a pattern determined by predicted changing flow rate patterns through the area of the substrate (7) during intervals of increasing accumulation of particulate matter against the filter (3) and effective to maximally sustain dispersion of active ingredient during such intervals.
权利要求：
WHAT IS CLAIMED IS:
1. A filter which disperses an active ingredient into a fluid which passes through said filter over a sustained period of use, the fluid containing entrained particulate matter to be retained by said filter, comprising a filter substrate defining an area and being porous to flow of the fluid through said substrate and which will block flow of the entrained particulate matter, and at least one active, ingredient capable of dispersion into the fluid applied to said filter substrate, said active at least one active ingredient being unevenly distributed on said filter substrate in a pattern determined by predicted changing flow rate patterns through the area of said substrate during intervals of increasing accumulation of particulate matter against the filter and effective to maximally sustain dispersion of active ingredient during said intervals.
2. The filter of claim 1 which counteracts a tendency of the accumulated particulate matter in said filter to act as a source which disperses unwanted materials into the fluid, in which a densest or most concentrated application of the at least one active ingredient applied to and on said filter substrate is in a portion of the area defined by the filter substrate in which preferential flow of the fluid occurs after accumulation of the particulate matter in the filter.
3. The filter of claim 1 in which the uneven distribution of said active ingredient is in varying densities over said filter substrate, such that the uneven distributionwill maintain a substantially uniform dispersion rate of active ingredients over time in use of said filter. 4. The filter of claim 3 in which said at least one active ingredient comprises a plurality of active ingredients on the filter substrate in a plurality of layers of varying density patterns.
5. The filter of claim 4 in which said plurality of layers each include a first active ingredient and a second active or inert ingredient in solid, dry powdered form adhered to the first active ingredient.
6. The filter of claim 5 in which the first active ingredient comprises a rubber, a polar solvent and a cationic surfactant.
7. The filter of claim 6 in which the second active ingredient comprises a perfume, deodorant or reodorant.
8. The filter of claim 7 in which the perfume, deodorant or reodorant is in a time released vehicle wherein a dispensation rate of the perfume, deodorant or reodorant can be selectively enhanced or retarded.
9. The filter of claim 1 in which the active ingredient includes a stabilizer.
10. The filter of claim 9 in which the stabilizer is a dye.
11. The filter of claim 10 in which the at least one active ingredient is a perfume, deodorant or reodorant having a given solubility parameter and chemical structure and the stabilizer is a polymer with a solubility parameter and chemical structure which closely match the given solubility parameter and chemical structure. 12. The filter of claim 11 in which the stabilizer is a bacteriostat or bactericide.
13. The filter of claim 11 in which the at least one active ingredient is an essential oil and the stabilizer is an antioxidant.
14. The filter of Claim 1 in which the uneven distribution is in a pattern covering less than all of said filter.
15. A process for fabricating a filter, which comprises providing a filter in the form of a filter substrate defining an area and being porous to a fluid which passes through the filter in use of the filter, measuring filtration rate distribution of the filter substrate by introducing a finely dividedmaterial into the fluid effluent, observing resultant patterns of placement of the finely divided material on the filter substrate, andusingthe resultantpatterns to establish a varying density of at least one active ingredient capable of dispersion into the filter on the filter for discharge with the fluid to sustain the effectiveness of the at least one active ingredient in use of the filter, thevaryingdensitybeing in a patterndetermined by predicted changing flow rate patterns from the resultant patterns through the area of the substrate during intervals of increasing accumulation of particulate matter against the filter and effective to maximallysustaindispersionof active ingredientduring the intervals.
16. The process of claim 15 additionally comprising the step of depositingthe at least one active ingredient on the filter in the varying density. 17. The process of claim 16 in which the at least one active ingredient is deposited on the filter substrate by printing.
18. The process of claim 15 in which a plurality of active ingredients are deposited on the filter substrate in a plurality of layers of varying density.
19. The process of claim 18 in which the plurality of layers are depositedwith amulti-layer printing press in a single pass.
20. The process of claim 18 in which the plurality of layers are deposited by the successive application of a first active ingredient in fluid form which will dry to a sticky or tacky finish, followed by the application of a second active ingredient or an inert ingredient in solid, dry powdered form to the filter substrate, and mechanical removal of the second active ingredient or inert ingredient which has not adhered to the first active ingredient.
21. The process of claim 20 in which the first active ingredient comprises a rubber, a polar solvent and a cationic surfactant.
22. The process of claim 21 in which the first active ingredient additionally comprises a perfume, deodorant or reodorant.
23. The process of claim 22 in which the perfume, deodorant or reodorant is in a time released vehicle wherein the dispensation rate of the perfume, deodorant or reodorant can be selectively enhanced or retarded. 24. The process of claim 15 in which the at least one active ingredient includes a stabilizer.
25. The process of claim 24 inwhich the stabilizer is a dye.
26. The process of claim 25 in which the at least one active ingredient is a perfume, deodorant or reodorant and the stabilizer is a polymer with a solubilityparameter and chemical structure which closely match a solubility parameter and chemical structure of the perfume, deodorant or reodorant.
27. The process of claim 26 in which the stabilizing ingredient is a bacteriostat orbactericide.
28. The process of claim 26 in which the at least one active ingredient is an essential oil and the stabilizer is an antioxidant.
29. The process of claim 15 in which the at least one active ingredient is deposited by mixing charged particles and a friable polymer with the active ingredients to form a powder mixture, and then using chargingconditions to deposit the powder mixture on the « filter substrate, and then heat setting the powder mixture in place.
30. The process of Claim 15 in which the varying density is established in a pattern including less than all of the filter.