Flame resistant paper product and method for manufacturing
View Patent ↗The invention relates to a flame resistant paper product and a method for manufacturing a flame resistant paper product. In an embodiment the invention is a paper product comprising a paper substrate having a first surface and a second surface and a flame retardant composition, wherein the first surface is smoother than the second surface. In another embodiment, the invention is a method for forming a flame resistant paper product comprising applying a flame retardant composition to a web of fibers having a first surface and a second surface, wherein the first surface is smoother than the second surface by at least about 70 SSU according to TAPPI T538.
1. A single-ply paper product comprising:
a machine-glazed paper substrate comprising a web of fibers and a sufficient amount of a flame retardant composition to provide the paper substrate with a flame resistance allowing a char length of less than 4.5 inches according to TAPPI T461;
the paper substrate comprising a first surface and a second surface and having a differential smoothness between the first surface and the second surface of at least about 70 SSU according to TAPPI T538, wherein the differential smoothness results from application of the paper substrate to a machine to impart machine-glazed properties to the first surface so that the first surface has a smoothness greater than 100 SSU according to TAPPI T538 and is smoother than the second surface, and wherein the flame retardant composition is applied to the second surface and not to the first surface after application of the paper substrate to the machine to impart machine-glazed properties.
2. A single-ply paper product according to claim 1 , wherein the differential smoothness between the first surface and the second surface is at least 100 SSU according to TAPPI T538.
3. A single-ply paper product according to claim 1 , wherein the first surface and the second surface have a differential gloss of at least 2 gloss units according to TAPPI T480.
4. A single-ply paper product according to claim 1 , wherein the first surface and the second surface have a differential gloss of at least 3 gloss units according to TAPPI T480.
5. A single-ply paper product according to claim 1 , wherein the web of fibers comprises at least 10% post-consumer waste fiber.
6. A single-ply paper product according to claim 1 , wherein the web of fibers comprises at least 20% post-consumer waste fiber.
7. A single-ply paper product according to claim 1 , wherein the web of fibers comprises at least 30% post-consumer waste fiber.
8. A single-ply paper product according to claim 1 , wherein the web of fibers comprises cellulose fiber from chemical pulped wood comprising at least one of coniferous and deciduous trees.
9. A single-ply paper product according to claim 1 , wherein the web of fibers comprises cellulose fiber from chemical pulped wood comprising at least one of hardwood and softwood.
10. A single-ply paper product according to claim 1 , wherein the web of fibers comprises bleached cellulose fiber.
11. A single-ply paper product according to claim 1 , wherein the flame retardant composition comprises at least one of ammonium sulfate, monoammonium phosphate, and diammonium phosphate.
12. A single-ply paper product according to claim 11 , wherein the flame retardant composition comprises ammonium sulfate and monoammonium phosphate.
13. A single-ply paper product according to claim 12 , comprising between 12 and 14 wt. % ammonium sulfate and between 5 and 7 wt. % monoammonium phosphate.
14. A single-ply paper product according to claim 1 , wherein the web of fibers has a weight of between 40 lbs./3,000 ft. 2 and 54 lbs./3,000 ft. 2 .
15. A single-ply paper product according to claim 14 , wherein the web of fibers has a weight of between 44 lbs./3,000 ft. 2 and 50 lbs./3,000 ft. 2 .
16. A single-ply paper product according to claim 1 , wherein the machine to impart machine-glazed properties comprises a drying cylinder having a smoothness-imparting surface.
17. A paper product according to claim 16 , wherein the paper product resists flame according to TAPPI test T461.
18. A paper product according to claim 16 , wherein the paper product has a char length of less than 5.5 inches according to TAPPI test T461.
19. A single-ply paper product according to claim 1 , wherein the first surface has a smoothness greater than 100 SSU to about 200 SSU according to TAPPI T538.
20. A single-ply paper product according to claim 1 , wherein the second surface has a smoothness greater than 150 SSU according to TAPPI T538.
21. A single-ply paper product according to claim 1 , wherein the second surface has a smoothness of about 200 SSU to about 280 SSU according to TAPPI T538.
22. A paper product comprising:
a machine-glazed paper substrate having a first surface and a second surface and comprising:
a web of fibers; and
a flame retardant composition;
wherein the first surface and the second surface have a differential smoothness of at least about 70 SSU according to TAPPI T538 wherein the differential smoothness results from application of the paper substrate to a machine to impart machine-glazed properties to the first surface so that the first surface has a smoothness greater than 100 SSU according to TAPPI T538 and is smoother than the second surface, and wherein the flame retardant composition is applied to the second surface of the paper substrate and not to the first surface after application of the paper substrate to the machine to impart machine-glazed properties.
23. A paper product according to claim 22 , wherein the first surface and the second surface have a differential smoothness of at least 100 SSU according to TAPPI T538.
24. A paper product according to claim 22 , wherein the first surface and the second surface have a differential gloss of at least 2 gloss units according to TAPPI T480.
25. A paper product according to claim 22 , wherein the first surface and the second surface have a differential gloss of at least 3 gloss units according to TAPPI T480.
26. A paper product according to claim 22 , wherein the web of fibers comprises at least 10% post-consumer waste fiber.
27. A paper product according to claim 22 , wherein the web of fibers comprises at least 20% post-consumer waste fiber.
28. A paper product according to claim 22 , wherein the web of fibers comprises at least 30% post-consumer waste fiber.
29. A paper product according to claim 22 , wherein the web of fibers comprises cellulose fiber from chemical pulped wood comprising at least one of coniferous and deciduous trees.
30. A paper product according to claim 22 , wherein the web of fibers comprises cellulose fiber from chemical pulped wood comprising at least one of hardwood and softwood.
31. A paper product according to claim 22 , wherein the web of fibers comprises bleached cellulose fiber.
32. A paper product according to claim 22 , wherein the flame retardant composition comprises at least one of ammonium sulfate, monoammonium phosphate, and diammonium phosphate.
33. A paper product according to claim 32 , wherein the flame retardant composition comprises ammonium sulfate and monoammonium phosphate.
34. A paper product according to claim 33 , comprising between 12 and 14 wt. % ammonium sulfate and between 5 and 7 wt. % monoammonium phosphate.
35. A paper product according to claim 22 , wherein the web of fibers has a weight of between 40 lbs./3,000 ft. 2 and 54 lbs./3,000 ft. 2 .
36. A paper product according to claim 22 , wherein the web of fibers has a weight of between 44 lbs./3,000 ft. 2 and 50 lbs./3,000 ft. 2 .
37. A paper product according to claim 22 , wherein the machine to impart machine-glazed properties comprises a drying cylinder having a smoothness-imparting surface.
38. A paper product according to claim 22 , wherein the first surface has a smoothness greater than 100 SSU to about 200 SSU according to TAPPI T538.
39. A paper product according to claim 22 , wherein the second surface has a smoothness greater than 150 SSU according to TAPPI T538.
40. A paper product according to claim 22 , wherein the second surface has a smoothness of about 200 SSU to about 280 SSU according to TAPPI T538.