Cut resistant paper and paper articles and method for making same

• US 20050098286A1
• Filed: 10/15/2004
• Published: 05/12/2005
• Est. Priority Date: 01/26/2000
• Status: Active Grant

• Current Assignee: International Paper Company
• Original Assignee: International Paper Company
• Inventors: Faber, Richard D., Froass, Peter M., Williams, Richard C., Boone, David A.
• Granted Patent: US 7,482,046 B2
• Time in Patent Office: Days
• US Class Current: 162/164.1
• CPC Class Codes: D21H 19/20 comprising macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds
• CPC Class Codes: D21H 19/22 Polyalkenes, e.g. polystyrene
• CPC Class Codes: D21H 19/28 Polyesters
• CPC Class Codes: D21H 21/54 being spherical, e.g. microcapsules, beads
• CPC Class Codes: D21H 27/10 Packing paper packaging materials of special type or form B65D65/38
• CPC Class Codes: Y10T 428/1303 Paper containing [e.g., paperboard, cardboard, fiberboard, etc.]
• CPC Class Codes: Y10T 428/1348 Cellular material derived from plant or animal source [e.g., wood, cotton, wool, leather, etc.]
• CPC Class Codes: Y10T 428/24215 Acute or reverse fold of exterior component
• CPC Class Codes: Y10T 428/26 Web or sheet containing structurally defined element or component, the element or component having a specified physical dimension
• CPC Class Codes: Y10T 428/277 Cellulosic substrate
• CPC Class Codes: Y10T 428/2985 Solid-walled microcapsule from synthetic polymer

Abstract

The specification discloses a method for making a paper material having a reduced tendency to cut human skin. The method includes providing a papermaking furnish containing cellulosic fibers and from about 0.5 to about 5.0 wt % by weight dry basis expandable microspheres, forming a paperboard web from the papermaking furnish, drying the web, and calendaring the web to a caliper of from about 11.0 to about 18.0 mils and a density ranging from about 7.0 to about 12.0 lb/3000 ft²/mil. Papers formed according to the method and articles formed therefrom are also disclosed.

Claims

1. A paper material for use in the manufacture of paper articles such as file folders comprising a paper web including cellulosic fibers and expanded microspheres, the paper web having a density of from about 7.0 to about 12.0 lb/3000 ft²/mil and a caliper after calendering of from about 11.0 to about 18.0 mils wherein the paper web has edges which exhibit an improved resistance to inflicting cuts upon human skin.

2. The paper material of claim 1 wherein the paper web has a density of from about 7.5 to about 9.0 lb/3000 ft²/mil.

3. The paper material of claim 1 wherein the paper web has a caliper of about 14.0 to about 16.0 mils.

4. The paper material of claim 1 wherein the expanded microspheres in the paper web comprise synthetic polymeric microspheres and comprise from about 0.5 to about 5.0 wt. % of the total weight of the web on a dry basis.

5. The paper material of claim 1 wherein the expanded microspheres in the paper web comprise synthetic polymeric microspheres and comprise from about 1.0 to about 2.0 wt. % of the total weight of the web on a dry basis.

6. The paper material of claim 1 wherein the paper web has a basis weight of from about 80 lb/3000 ft² to about 300 lb/3000 ft².

7. The paper material of claim 1 wherein the paper web has a basis weight of from about 120 lb/3000 ft² to about 150 lb/3000 ft².

8. The paper material of claim 1 wherein the expanded microspheres in the paper web comprise microspheres made from a polymeric material selected from the group consisting of methyl methacrylate, ortho-chlorostyrene, polyortho-chlorostyrene, polyvinylbenzyl chloride, acrylonitrile, vinylidene chloride, para-tert-butyl styrene, vinyl acetate, butyl acrylate, styrene, methacrylic acid, vinylbenzyl chloride and combinations of two or more of the foregoing.

9. The paper material of claim 1 wherein the fibers in the paper web comprise from about 30 to about 100% by weight dry basis softwood fibers and from about 70 to about 0% by weight dry basis hardwood fibers.

10. The paper material of claim 1 wherein the microspheres have an expanded diameter of from about 30 to about 60 microns.

11. The paper material of claim 1 wherein the microspheres are dispersed within the furnish in an unexpanded state and subsequently expand as the paper web dries.

12. The paper material of claim 1 wherein the paper material exhibits a Cutting Index of less than about 40 when analyzed according to the Cutting Index 30 test.

13. A method for making a paper material having a reduced tendency to cut human skin comprising providing a papermaking furnish containing cellulosic fibers and from about 0.5 to about 5.0 wt % by weight dry basis expanded or expandable microspheres, forming a fibrous web from the papermaking furnish, drying the web, and calendaring the web to a caliper of from about 11.0 to about 18.0 mils and a density ranging from about 7.0 to about 12.0 lb/3000 ft²/mil.

14. The method of claim 13 wherein the web has a density of from about 7.5 to about 9.0 lb/3000 ft²/mil.

15. The method of claim 13 wherein the web has a caliper of about 14.0 to about 16.0 mils.

16. The method of claim 13 wherein the microspheres in the web comprise synthetic polymeric microspheres and comprise from about 0.5 to about 5.0 wt. % of the total weight of the web on a dry basis.

17. The method of claim 13 wherein the microspheres in the web comprise synthetic polymeric microspheres and comprise from about 1.0 to about 2.0 wt. % of the total weight of the web on a dry basis.

18. The method of claim 13 wherein the web has a basis weight of from about 80 lb/3000 ft² to about 3000 lb/3000 ft².

19. The method of claim 13 wherein the web has a basis weight of from about 120 lb/3000 ft² to about 150 lb/3000 ft².

20. The method of claim 13 wherein the microspheres in the web comprise microspheres made from a polymeric material selected from the group consisting of methyl methacrylate, ortho-chlorostyrene, polyortho-chlorostyrene, polyvinylbenzyl chloride, acrylonitrile, vinylidene chloride, para-tert-butyl styrene, vinyl acetate, butyl acrylate, styrene, methacrylic acid, vinylbenzyl chloride and combinations of two or more of the foregoing.

21. The method of claim 13 wherein the fibers in the web comprise from about 30 to about 100% by weight dry basis softwood fibers and from about 70 to about 0% by weight dry basis hardwood fibers.

22. The method of claim 13 wherein the microspheres have an expanded diameter of from about 30 to about 60 microns.

23. The method of claim 13 wherein the microspheres are dispersed within the fibers in an unexpanded state and subsequently expand as the paper web dries.

24. The method of claim 13 wherein the web exhibits a Cutting Index of less than about 40 when analyzed according to the Cutting Index 30 test.

25. A file folder or jacket comprising a paper web including wood fibers and expanded microspheres dispersed within the fibers and having a density of from about 7.0 to about 12.0 lb/3000 ft²/mil and a caliper of from about 11.0 to about 18.0 mils wherein the paper web is die cut to provide a blank having exposed edges and the blank is formed into a file folder or jacket and wherein the edges of said folder or jacket exhibit an improved resistance to inflicting cuts upon human skin.

26. The file folder or jacket of claim 25 wherein the paper web has a density of from about 7.5 to about 9.0 lb/3000 ft²/mil

27. The file folder or jacket of claim 25 wherein the paper web has a caliper of about 14.0 to about 16.0 mils.

28. The file folder or jacket of claim 25 wherein the expanded microspheres in the paper web comprise synthetic polymeric microspheres and comprise from about 0.5 to about 5.0 wt. % of the total weight of the web on a dry basis.

29. The file folder or jacket of claim 25 wherein the expanded microspheres in the paper web comprise synthetic polymeric microspheres and comprise from about 1.0 to about 2.0 wt. % of the total weight of the web on a dry basis.

30. The file folder or jacket of claim 25 wherein the paper web has a basis weight of from about 80 lb/3000 ft² to about 300 lb/3000 ft².

31. The file folder or jacket of claim 25 wherein the paper web has a basis weight of from about 120 lb/3000 ft² to about 150 lb/3000 ft².

32. The file folder or jacket of claim 25 wherein the expanded microspheres in the paper web comprise microspheres made from a polymeric material selected from the group consisting of methyl methacrylate, ortho-chlorostyrene, polyortho-chlorostyrene, polyvinylbenzyl chloride, acrylonitrile, vinylidene chloride, para-tert-butyl styrene, vinyl acetate, butyl acrylate, styrene, methacrylic acid, vinylbenzyl chloride and combinations of two or more of the foregoing.

33. The paper material of claim 25 wherein the fibers in the paper web comprise from about 30 to about 100% by weight dry basis softwood fibers and from about 70 to about 0% by weight dry basis hardwood fibers.

34. The file folder or jacket of claim 25 wherein the microspheres have an expanded diameter of from about 30 to about 60 microns.

35. The file folder or jacket of claim 25 wherein the microspheres are dispersed within the wood fibers in an unexpanded state and subsequently expand as the paper web dries.

36. The file folder or jacket of claim 25 wherein the folder or jacket exhibits a Cutting Index of less than about 40 when analyzed according to the Cutting Index 30 test.