Agglomerated cellulosic particles

• US 4,621,011 A
• Filed: 09/30/1985
• Issued: 11/04/1986
• Est. Priority Date: 04/24/1984
• Status: Expired due to Term

• Current Assignee: Kadant Fibergen, Inc. (Kadant Incorporated)
• Original Assignee: Kimberly-Clark Corporation
• Inventors: Harke, Elwood W., Fleischer, Glen R., Fay, James E., Sokolowski, Robert C., Glashagel, Barry B.
• Primary Examiner(s): Bell, James J.
• Application Number:
  US06/782,242
• Time in Patent Office: 400 Days
• Field of Search: 119/1, 428/221, 428/357, 428/372, 428/326, 428/398, 428/400
• US Class Current: 428/221
• CPC Class Codes: A01K 1/0152 Litter
• CPC Class Codes: A01K 1/0155 comprising organic material
• CPC Class Codes: C08J 11/06 without chemical reactions
• CPC Class Codes: C08J 2301/02 Cellulose; Modified cellulose
• CPC Class Codes: C08L 1/02 Cellulose; Modified cellulose
• CPC Class Codes: Y02W 30/62 Plastics recycling; Rubber recycling
• CPC Class Codes: Y10T 428/249921 Web or sheet containing structurally defined element or component
• CPC Class Codes: Y10T 428/253 Cellulosic [e.g., wood, paper, cork, rayon, etc.]
• CPC Class Codes: Y10T 428/29 Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof
• CPC Class Codes: Y10T 428/2927 including structurally defined particulate matter
• CPC Class Codes: Y10T 428/2975 Tubular or cellular
• CPC Class Codes: Y10T 428/2978 Surface characteristic

Abstract

A cellulosic particle, especially useful as a cat litter, is manufactured by agglomerating a fibrous cellulosic feed material in the presence of water, compacting the surface of the agglomerated particles, and drying the particles.

Claims

1. A particle having a compacted outer surface comprises fibrous cellulosic material and has a bulk density of about 0.15 to about 0.9 kg. per liter.

2. The particle of claim 1 wherein the greatest dimension of said material is less than about 0.25 inch.

3. The particle of claim 2 wherein said particle is substantially free of protruding fibrils.

4. The particle of claim 1 having a platelet-like shape.

5. The particle of claim 1 wherein the ratio of z dimension to x dimension of said particle is from about 0.06:

1 to about 0.6;

1.

6. The particle of claim 5 where said z/x ratio ranges from about 0.15:

1 to about 0.5;

1.

7. The particle of claim 1 wherein the size of said particle ranges from about 0.03 inch to about 0.5 inch.

8. The particle of claim 7 wherein said particle size ranges from about 0.6 to about 0.25 inch.

9. The particle of claim 1 wherein about 98 weight percent of said particles pass a U.S. Sieve #4 and less than about 0.1 weight percent pass through a U.S. Sieve #18.

10. The particle of claim 1 wherein said particle is attrition resistant.

11. The particle of claim 10 wherein less than about 2 percent of said particles are attrited during a 1000 mile attrition test to the next smaller U.S. Sieve number.

12. The particle of claim 11 wherein said attrition test does not produce a measurable increase in said particles retained on a U.S. Sieve #140 or smaller.

13. The particle of claim 1 having a Dust Level Index of about 10 or less.

14. The particle of claim 1 wherein said particle remains discrete following wetting.

15. The particle of claim 1 wherein the ratio of x-dimension to y-dimension is not greater than about 3:

1.

16. The particle of claim 4 wherein said particle is generally circular.

17. The particle of claim 1 wherein the 24-hour evaporation rate of said particle is about two times that of clay litters.

18. The particle of claim 17 wherein the 24-hour aqueous evaporation rate of said particle is at least about 0.0040#/hr.

19. The particle of claim 1 wherein said particle is particularly useful of oil sorption in the substantial absence of dust.

20. The particle of claim 19 wherein said particle sorbs oil to at least 75 percent of its weight.

37. The bed of claim 1 wherein the 24-hour evaporation rate of said particles is about two times that of clay litter.

38. The bed of claim 19 wherein the 24-hour aqueous evaporation rate of said particles is at least about 0.0040#/hr.

21. A bed of particles comprising fibrous cellulosic material, said particles having a compacted outer surface and a bulk density of 0.15 to about 0.9 kg. per liter.

22. The bed of claim 21 wherein said particles have platelet-like shape.

23. The bed of claim 21 wherein the greatest dimension of said material is less than about 0.25 inch.

24. The bed of claim 21 wherein said particles are substantially free of protruding fibrils.

25. The bed of claim 24 wherein said bed has a Dust Level Index of about 10 or less.

26. The bed of claim 21 wherein the ratio of z dimension to x dimension of said particle is from about 0.06:

1 to about 0.6;

1.

27. The bed of claim 26 where said z/x ratio ranges from about 0.15:

1 to about 0.5;

1.

28. The bed of claim 21 wherein the size of said particle ranges from about 0.03 inch to about 0.5 inch.

29. The bed of claim 28 wherein said particle size ranges from about 0.6 to about 0.25 inch.

30. The bed of claim 21 wherein said particles comprise about 98 weight percent which pass a U.S. Sieve #4 and less than about 0.1 weight percent pass through a U.S. Sieve #18.

31. The bed of claim 21 wherein said particles are attrition resistant.

32. The bed of claim 31 wherein less than about 2 percent of said particles are attrited during a 1000 mile attrition test to the next smaller U.S. Sieve number.

33. The bed of claim 32 wherein said attrition test does not produce a measurable increase in said particles retained on a U.S. Sieve #140 or smaller.

34. The bed of claim 21 wherein said particles remain discrete following wetting.

35. The bed of claim 21 wherein the ratio of x-dimension to y-dimension is not greater than about 3:

1.

36. The bed of claim 22 wherein said particles are generally circular.

39. The bed of particles of claim 21 wherein said bed is as stable as clay litter.