Multifunctional fibrous material with improved edge seal

• US 6,559,081 B1
• Filed: 05/25/2000
• Issued: 05/06/2003
• Est. Priority Date: 05/25/1999
• Status: Expired due to Term

• Current Assignee: Georgia-Pacific Nonwovens LLC (KOCH Industries Incorporated)
• Original Assignee: BKI Holding Corp. (KOCH Industries Incorporated)
• Inventors: Hurley, Jeffrey S., Erspamer, John P., Betts, Derrix, Boehmer, Brian E.
• Primary Examiner(s): Morris, Terrel
• Assistant Examiner(s): JOHNSON, JENNA LEIGH
• Application Number:
  US09/578,603
• Time in Patent Office: 1,076 Days
• Field of Search: 442/381, 442/389, 442/385, 442/393, 442/409, 442/411, 442/415, 442/416, 442/417, 442/392, 428/166, 428/167, 428/168, 428/320.2, 428/165, 428/195, 428/196, 604/367
• US Class Current: 442/392
• CPC Class Codes: A61F 13/00 Bandages or dressings radioactive dressings A61N5/1029; Absorbent pads
• CPC Class Codes: A61F 13/15617 Making absorbent pads from fibres or pulverulent material with or without treatment of the fibres
• CPC Class Codes: A61F 13/5323 having absorbent material located in discrete regions, e.g. pockets
• CPC Class Codes: B32B 2255/02 on fibrous or filamentary layer
• CPC Class Codes: B32B 2255/26 Polymeric coating
• CPC Class Codes: B32B 2262/0215 Thermoplastic elastomer fibers
• CPC Class Codes: B32B 2262/062 Cellulose fibres, e.g. cotton
• CPC Class Codes: B32B 2262/12 Conjugate fibres, e.g. core/sheath or side-by-side
• CPC Class Codes: B32B 2262/14 Mixture of at least two fibres made of different materials
• CPC Class Codes: B32B 2264/02 Synthetic macromolecular particles
• CPC Class Codes: B32B 2264/10 Inorganic particles
• CPC Class Codes: B32B 2307/31 Heat sealable
• CPC Class Codes: B32B 2307/50 having particular mechanical properties
• CPC Class Codes: B32B 2307/546 Flexural strength; Flexion stiffness
• CPC Class Codes: B32B 2307/726 Permeability to liquids, absorption
• CPC Class Codes: B32B 2307/7265 Non-permeable
• CPC Class Codes: B32B 2432/00 Cleaning articles, e.g. mops or wipes
• CPC Class Codes: B32B 2555/00 Personal care
• CPC Class Codes: B32B 2555/02 Diapers or napkins
• CPC Class Codes: B32B 3/02 characterised by features of form at particular places, e.g. in edge regions non-uniform thickness B32B3/263
• CPC Class Codes: B32B 3/08 : characterised by added members at particular parts layer formed of separate pieces of material which are juxtaposed side-by-side B32B3/14, B32B3/18
• CPC Class Codes: B32B 5/00 : Layered products characterised by the non- homogeneity or physical structure , i.e. comprising a fibrous, filamentary, particulate or foam layer; Layered products characterised by having a layer differing constitutionally or physically in different parts
• CPC Class Codes: B32B 5/02 : characterised by structural features of a fibrous or filamentary layer layer formed of metallic wires B32B15/02; layer formed of natural mineral fibres B32B19/02; layer formed of wood fibres B32B21/02
• CPC Class Codes: B32B 5/08 : the fibres or filaments of a layer being of different substances , e.g. conjugate fibres, mixture of different fibres
• CPC Class Codes: B32B 5/26 : another layer next to it also being fibrous or filamentary relative arrangement of fibres or filaments of different layers B32B5/12
• CPC Class Codes: D04H 1/413 : containing granules other than absorbent substances
• CPC Class Codes: D04H 1/4374 : using different kinds of webs, e.g. by layering webs
• CPC Class Codes: Y10T 428/24554 : including cellulosic or natural rubber component
• CPC Class Codes: Y10T 428/24562 : Interlaminar spaces
• CPC Class Codes: Y10T 428/2457 : Parallel ribs and/or grooves
• CPC Class Codes: Y10T 428/24579 : with particulate matter
• CPC Class Codes: Y10T 428/2481 : including layer of mechanically interengaged strands, strand-portions or strand-like strips
• CPC Class Codes: Y10T 442/664 : Including a wood fiber containing layer
• CPC Class Codes: Y10T 442/671 : Multiple nonwoven fabric layers composed of the same polymeric strand or fiber material
• CPC Class Codes: Y10T 442/673 : Including particulate material other than fiber
• CPC Class Codes: Y10T 442/692 : Containing at least two chemically different strand or fiber materials
• CPC Class Codes: Y10T 442/697 : Containing at least two chemically different strand or fiber materials
• CPC Class Codes: Y10T 442/698 : Containing polymeric and natural strand or fiber materials
• CPC Class Codes: Y10T 442/699 : Including particulate material other than strand or fiber material

Abstract

This invention relates to fibrous absorbent articles containing particles useful in the manufacture of disposable diapers, adult incontinence pads, sanitary napkins and the like, scrubbing pads, scouring pads and cleaning pads that contain a detergent or soap and the like, and pads that contain coffee, tea, and the like More particularly, the invention is directed to an absorbent articles having sealed lateral edges to contain loose fibers and particles within the structure. Additionally, this invention is related to airlaid methods to manufacture unitary absorbent products.

Claims

1. A fibrous web comprising:

(a) a lower stratum comprising thermoplastic fibers and matrix fibers which are cellulosic fibers or a blend of cellulosic fibers and synthetic fibers; and

(b) an upper stratum comprising thermoplastic fibers and matrix fibers which are cellulosic fibers or a blend of cellulosic fibers and synthetic fibers;

wherein a plurality of functional particle areas comprised of superabsorbent polymers are positioned between said upper stratum and said lower stratum so as to contact each of said upper and lower strata, each of said functional particle areas being separated from other functional particle areas by a seal area comprising a seal formed between said upper and said lower strata.

2. The fibrous web of claim 1 wherein said seal area is substantially free of functional parties.

3. The fibrous web of claim 1 wherein said thermoplastic fibers are bicomponent fibers.

4. The fibrous web of claim 1 wherein said functional particle area comprises superabsorbent polymers.

5. The fibrous web of claim 4 wherein said functional particle area further comprises zeolites.

6. The fibrous web of claim 1, further comprising a binder on the entire surface of the fibrous web.

7. The fibrous web of claim 1 wherein said seal is formed by the application of pressure and/or heat.

8. The fibrous web of claim 1 wherein a binder is applied onto said seal area, said binder having a binder solids concentration of from 3 to 25% by weight, based on the total weight of the binder.

9. The fibrous web of claim 8 wherein said binder is applied onto said seal area is a latex binder.

10. The fibrous web of claim 1 having a powder spillage value of not more than 1.0 mg.

11. The fibrous web of claim 1 having a peak seal strength of greater than 0.6 N.

12. The fibrous web of claim 1 having a stiffness in the seal area of less than 150 mg.

13. The fibrous web of claim 1 having a stiffness in the non-seal area of less than 200mg.

14. An absorbent article comprising:

(a) a lower stratum comprising thermoplastic fibers and cellulosic fibers or a blend of cellulosic fibers and synthetic fibers;

(b) an upper stratum comprising thermoplastic fibers and cellulosic fibers or a blend of cellulosic fibers and synthetic fibers;

(c) a functional particle area comprised of superabsorbent polymers positioned between said upper stratum and said lower stratum so as to contact each of said upper and lower strata; and

(d) a seal area comprising a seal formed between said upper and said lower strata, said seal area being substantially free of functional particles.

15. The article of claim 14 said article comprising two said seal areas, wherein said seal areas are disposed on opposing edges of said article.

16. The article of claim 14 wherein said thermoplastic fibers are bicomponent fibers.

17. The article of claim 14 wherein said functional particle area further comprises zeolites.

18. The article of claim 14 wherein said seal is formed by the application of pressure and/or heat.

19. The article claim 14, said article further comprising a binder on the entire surface.

20. The article of claim 19 wherein a binder is applied onto said seal area, said binder having a binder solids concentration of from 3 to 25% by weight, based on 100% total weight of the binder.

21. The article of claim 20 wherein said binder applied onto said seal area is a latex binder.

22. The article of claim 14 having a powder spillage value of not more than 1.0 mg.

23. The article of claim 14 having a peak seal strength of greater than0.6 N.

24. The article of claim 19 wherein said binder is present in the amount of less than 5% by weight of said article.

25. The article of claim 14 having a stiffness in the seal area of less than 150 mg.

26. The article of claim having a stiffness in the non-seal area of less than 200 mg.

27. An absorbent article comprising:

(a) a fluid pervious topsheet;

(b) a second stratum in fluid contact with said fluid pervious top sheet, said stratum comprising thermoplastic fibers and cellulosic fibers or a blend of cellulosic fibers and synthetic fibers;

(c) an upper stratum comprising thermoplastic fibers and cellulosic fibers or a blend of cellulosic fibers and synthetic fibers;

(d) a functional particle area comprised of superabsorbent polymers positioned between said upper stratum and said lower stratum so as to contact each of said upper and lower strata;

(e) a seal area comprising a seal formed between said upper and said lower strata, said seal area being substantially free of functional particles; and

(f) a fluid impervious backsheet.

28. The absorbent article of claim 27 wherein said article is selected from the group of a diaper, an adult incontinence product and s feminine hygiene product.