Catamenial absorbent structures having thermally bonded layers for improved handling of menstrual fluids, and their use in catamenial pads having improved fit and comfort

• US 5,607,414 A
• Filed: 07/03/1995
• Issued: 03/04/1997
• Est. Priority Date: 10/21/1993
• Status: Expired due to Term

• Current Assignee: The Procter & Gamble Company
• Original Assignee: The Procter & Gamble Company
• Inventors: Haney, Anna R., Keeler, Sheri D., Noel, John R., Lloyd, Susan N. W., Mackey, Larry N., Lee, Yann-Per, Richards, Mark R., Hammons, John L.
• Primary Examiner(s): Weiss, John G.
• Assistant Examiner(s): ZUTTARELLI, ANTHONY
• Application Number:
  US08/479,096
• Time in Patent Office: 610 Days
• Field of Search: 604/358, 604/365-370, 604/372, 604/378, 604/379, 604/385.1
• US Class Current: 604/378
• CPC Class Codes: A61F 13/15203 Properties of the article, e.g. stiffness or absorbency chemical aspects A61L15/00
• CPC Class Codes: A61F 13/53713 the layer having a promotional function on liquid propagation in the vertical direction
• CPC Class Codes: A61F 13/53717 the layer having a promotional function on liquid propagation in the horizontal direction
• CPC Class Codes: A61F 13/53743 characterised by the position of the layer relative to the other layers
• CPC Class Codes: A61F 13/539 characterised by the connection of the absorbent layers with each other or with the outer layers
• CPC Class Codes: A61F 2013/53721 with capillary means

Abstract

Thermally bonded absorbent structures for catamenial products, in particular catamenial pads, that provide improved ability in acquiring, distributing and storing aqueous body fluids, especially menstrual fluids, as well as better fit and comfort for the user of the products. These structures comprise an optional thermally bonded secondary topsheet, a thermally bonded absorbent core having a relatively higher capillary suction primary fluid distribution layer, an optional but preferred relatively lower capillary suction secondary distribution layer, a storage layer having absorbent gelling material, and an optional fibrous "dusting" layer. These thermally bonded absorbent structures are particularly useful with catamenial pads having a primary fluid pervious topsheet selected from apertured formed film topsheets and high loft nonwoven topsheets.

Claims

1. A catamenial pad capable of acquiring, distributing and storing aqueous body fluids, which comprises:

(A) a fluid pervious topsheet selected from the group consisting of apertured formed film topsheets and high loft nonwoven topsheets;

(B) an absorbent core in fluid communication with said topsheet and having;

(1) a primary fluid distribution layer comprising a mixture of hydrophilic cellulosic fibers and thermoplastic material bonding said fibers together into a thermally bonded matrix;

(2) a fluid storage layer in fluid communication with said primary layer, and comprising from about 15 to 100% by weight of said storage layer of absorbent gelling material and from 0 to about 85% by weight of said storage layer of a carrier for said absorbent gelling material;

(D) a fluid impervious backsheet;

(E) wherein the pad has;

(1) a compressive force value in the dry state of about 300 g or less;

(2) an absolute recovery from compression value in the wet state of at least about 48 mm; and

(3) a relative recovery from compression value in the wet state of at least about 65% of the initial pad width.

2. An absorbent core for aqueous body fluids, which comprises:

(A) a primary fluid distribution layer comprising a mixture of hydrophilic cellulosic fibers and thermoplastic material bonding said fibers together into a thermally bonded matrix providing vertical wicking of from about 8 to about 20 cm of artificial menstrual fluid;

(B) a secondary fluid distribution layer in fluid communication with, and which can partition aqueous body fluids from, said distribution layer, said secondary distribution layer comprising a mixture of hydrophilic cellulosic fibers and thermoplastic material bonding said fibers together into a thermally bonded matrix providing vertical wicking of from about 1 to about 6 cm of artificial menstrual fluid;

(C) a fluid storage layer in fluid communication with said secondary distribution layer and comprising from about 15 to 100% by weight of said storage layer of absorbent gelling material and from 0 to about 85% by weight of said storage layer of a carrier for said absorbent gelling material.

3. A catamenial product which comprises a fluid pervious topsheet made from an apertured formed film or nonwoven material;

a fluid impervious backsheet; and

the absorbent core of claim 2 positioned between said topsheet and said backsheet.

4. The catamenial product of claim 3 which is selected from the group consisting of pantiliners and incontinence pads.

5. The absorbent structure of claim 2 which further comprises a fibrous layer (D) adjacent said storage layer and comprising a mixture of hydrophilic cellulosic fibers and thermoplastic material bonding said fibers together into a thermally bonded matrix.

6. The absorbent core of claim 5 in which at least two layers (A), (B), and (D) are integrated together by thermal bonding.

7. An absorbent structure for aqueous body fluids, which comprises:

(A). a fluid acquisition layer comprising a mixture of hydrophilic cellulosic fibers and thermoplastic material bonding said fibers together into a thermally bonded matrix providing vertical wicking of from about 1 to about 6 cm of artificial menstrual fluid;

(B) a fluid distribution layer in fluid communication with, and which can acquire aqueous body fluids from, said acquisition layer, said distribution layer comprising a mixture of hydrophilic cellulosic fibers and thermoplastic material bonding said fibers together into a thermally bonded matrix providing vertical wicking of from about 8 to about 20 cm of artificial menstrual fluid;

(C) a fluid storage layer in fluid communication with said distribution layer and comprising from about 15 to 100% by weight of said storage layer of absorbent gelling material and from 0 to about 85% by weight of said storage layer of a carrier for said absorbent gelling material.

8. A catamenial product which comprises a fluid pervious topsheet made from an apertured formed film or nonwoven material;

a fluid impervious backsheet and the absorbent structure of claim 7 between said topsheet and said backsheet.

9. The product of claim 8 selected from the group consisting of pantiliners and incontinence pads.

10. The absorbent structure of claim 7 wherein said thermally bonded matrices of said acquisition layer (A) provides vertical wicking of from about 2 to about 4 cm of artificial menstrual fluid.

11. The absorbent structure of claim 10 wherein said acquisition layer (A) has a wet density in the range of from about 0.03 to about 0.07 g/cc.

12. The absorbent structure of claim 10 wherein said thermally bonded matrix of said distribution layer (B) provides vertical wicking of from about 11 to about 16 cm of artificial menstrual fluid.

13. The absorbent structure of claim 12 wherein said distribution layer (B) has a wet density in the range of from about 0.075 to about 0.15 g/cc.

14. The absorbent structure of claim 13 wherein said distribution layer (B) has a wet density in the range of from about 0.10 to about 0.15 g/cc and wherein said storage layer (C) comprises absorbent gelling material in an amount of from about 80 to about 150 gsm.

15. The absorbent structure of claim 7 which further comprises a fibrous layer (D) adjacent said storage layer and comprising a mixture of hydrophilic cellulosic fibers and thermoplastic material bonding said fibers together into a thermally bonded matrix.

16. The absorbent structure of claim 15 in which at least two of layers

(A), (B), and (D) are integrated together by thermal bonding.

17. The absorbent structure of claim 15 wherein said thermally bonded matrices of each of said layers (A), (B) and (D) are formed from a mixture of comprising from about 10 to 95% wood pulp fibers and from about 5 to about 90% thermoplastic binder fibers.

18. The absorbent structure of claim 17 wherein storage layer (C) comprises from about 30 to 100% absorbent gelling materials and from 0 to about 70% carrier.

19. The absorbent structure of claim 18 wherein storage layer (C) comprises from about 60 to 100% absorbent gelling materials and from 0 to about 40%, carrier.

20. The absorbent structure of claim 17 wherein said thermally bonded matrices of each of said layers (A), (B) and (D) are formed from a mixture comprising from about 55 to about 90% wood pulp fibers and from about 10 to about 45% thermoplastic binder fibers.

21. The absorbent structure of claim 20 wherein said thermally bonded matrix of said layer (B) is formed from a mixture having a basis weight of from about 50 to about 200 gsm and comprising from about 80 to about 90% wood pulp fibers and from about 10 to about 20% thermoplastic bicomponent binder fibers.

22. The absorbent structure of claim 20 wherein said thermally bonded matrix of said layer (B) is formed from a mixture having a basis weight of from about 80 to about 180 gsm and comprising from about 85 to about 95% wood pulp fibers and from about 5 to about 15% thermoplastic binder fibers.

23. The absorbent structure of claim 20 wherein said thermally bonded matrix of said layer (A) is formed from a mixture having a basis weight of from about 40 to about 60 gsm. and comprising from about 45 to about 90% wood pulp fibers;

up to about 30% hydrophilic nonbonding thermoplastic fibers, and from about 5 to about 50% thermoplastic bicomponent binder fibers.

24. The absorbent structure of claim 23 wherein said thermally bonded matrix of said layer (A) is formed from a mixture having a basis weight of from about 45 to about 55 gsm and comprising from about 65 to about 90% wood pulp fibers, from about 10 to about 20% hydrophilic nonbonding thermoplastic fibers, and from about 10 to about 20% thermoplastic binder fibers.

25. The absorbent structure of claim 23 wherein said thermally bonded matrix of said layer (D) is formed from a mixture comprising from about 85 to about 90% wood pulp fibers and from about 5 to about 10% thermoplastic bicomponent binder fibers.

26. An absorbent structure capable of acquiring, distributing and storing aqueous body fluids which comprises:

(A). a fluid acquisition layer comprising a mixture of hydrophilic cellulosic fibers and thermoplastic material bonding said fibers together into a thermally bonded matrix providing vertical wicking of from about 1 to about 6 cm of artificial menstrual fluid; and

(B) a primary fluid distribution layer comprising a mixture of hydrophilic cellulosic fibers and thermoplastic material bonding said fibers together into a thermally bonded matrix providing vertical wicking of from about 11 to about 16 cm of artificial menstrual fluid;

(C) a secondary fluid distribution layer in fluid communication with, and which can acquire aqueous body fluids from, said primary distribution layer, said secondary distribution layer comprising a mixture of hydrophilic cellulosic fibers and thermoplastic material bonding said fibers together into a thermally bonded matrix providing vertical wicking of from about 1 to about 6 cm of artificial menstrual fluid;

(D) a fluid storage layer in fluid communication with one of said primary and secondary distribution layers, and comprising from about 15 to 100% by weight of said storage layer of absorbent gelling material and from 0 to about 85% by weight of said storage layer of a carrier for said absorbent gelling material.

27. The absorbent structure of claim 26 in which at least two of layers (A), (B), (C) and (D) are integrated together by thermal bonding.

28. A catamenial product which comprises a fluid pervious topsheet made from an apertured formed film or nonwoven material;

a fluid impervious back sheet and the absorbent structure of claim 26 positioned between said primary topsheet and said backsheet.

29. The product of claim 28 selected from the group consisting of pantiliners and incontinence pads.

30. The absorbent structure of claim 26 wherein said thermally bonded matrices of said layers (A) and (C) provide vertical wicking of from about 2 to about 4 cm of artificial menstrual fluid.

31. The absorbent structure of claim 30 wherein said layers (A) and (C) have a wet density in the range of from about 0.03 to about 0.07 g/co.

32. The absorbent structure of claim 30 wherein said layer (B) has a wet density in the range of from about 0.075 to about 0.15 g/cc.

33. The absorbent structure of claim 32 wherein said layer (B) has a wet density in the range of from about 0.10 to about 0.15 g/cc and wherein said storage layer (D) comprises absorbent gelling material in an amount of from about 80 to about 150 gsm.

34. The absorbent structure of claim 26 which further comprises a fibrous layer (E) adjacent said storage layer and comprising a mixture of hydrophilic cellulosic fibers and thermoplastic material bonding said fibers together into a thermally bonded matrix.

35. The absorbent structure of claim 34 wherein said thermally bonded matrices of each of said layers (A), (B), (C) and (E) are formed from a mixture of comprising from about 10 to 95% wood pulp fibers and from about 5 to about 90% thermoplastic binder fibers.

36. The absorbent structure of claim 29 wherein storage layer (D) comprises from about 30 to 100% absorbent gelling materials and from 0 to about 70% carrier.

37. The absorbent structure of claim 35 wherein said thermally bonded matrices of each of said layers (A), (B), (C) and (E) are formed from a mixture comprising from about 55 to about 90% wood pulp fibers and from about 10 to about 45% thermoplastic binder fibers.

38. The absorbent structure of claim 37 wherein said thermally bonded matrix of said layer (B) is formed from a mixture having a basis weight of from about 80 to about 180 gsm and comprising from about 85 to about 95% wood pulp fibers and from about 5 to about 15% thermoplastic binder fibers.

39. The absorbent structure of claim 37 wherein said thermally bonded matrix of said layer (B) is formed from a mixture having a basis weight of from about 50 to about 200 gsm and comprising from about 80 to about 90% wood pulp fibers and from about 10 to about 20% thermoplastic binder fibers.

40. The absorbent structure of claim 39 wherein storage layer (D) comprises from about 60 to 100% absorbent gelling materials and from 0 to about 40%, carrier.

41. The absorbent structure of claim 37 wherein said thermally bonded matrices of each of said layers (A) and (C) are formed from a mixture having a basis weight of from about 40 to about 60 gsm. and comprising from about 45 to about 90% wood pulp fibers;

up to about 30% hydrophilic nonbonding thermoplastic fibers, and from about 5 to about 50% thermoplastic bicomponent binder fibers.

42. The absorbent structure of claim 41 wherein said thermally bonded matrices of each of said layers (A) and (C) are formed from a mixture having a basis weight of from about 45 to about 55 gsm and comprising from about 65 to about 90% wood pulp fibers, from about 10 to about 20% hydrophilic nonbonding thermoplastic fibers, and from about 10 to about 20% thermoplastic bicomponent binder fibers.

43. The absorbent structure of claim 41 wherein said thermally bonded matrix of said layer (E) is formed from a mixture comprising from about 85 to about 90% wood pulp fibers and from about 5 to about 10% thermoplastic bicomponent binder fibers.

44. A catamenial pad capable of acquiring, distributing and storing aqueous body fluids, which comprises:

(A) a fluid pervious topsheet selected from the group consisting of apertured formed film topsheets and high loft nonwoven topsheets;

(B) a fluid acquisition layer adjacent said topsheet, said acquisition layer comprising a mixture of hydrophilic cellulosic fibers and thermoplastic material bonding said fibers together into a thermally bonded matrix providing vertical wicking of from about 1 to about 6 cm of artificial menstrual fluid;

(C) an absorbent core in fluid communication with said fluid acquisition layer and having;

(1) a primary fluid distribution layer comprising a mixture of hydrophilic cellulosic fibers and thermoplastic material bonding said fibers together into a thermally bonded matrix providing vertical wicking of from about 8 to about 20 cm of artificial menstrual fluid;

(2) a secondary fluid distribution layer in fluid communication with, and which can acquire aqueous body fluids from, said primary distribution layer, said secondary distribution layer comprising a mixture of hydrophilic cellulosic fibers and thermoplastic material bonding said fibers together into a thermally bonded matrix providing vertical wicking of from about 1 to about 6 cm of artificial menstrual fluid;

(3) a fluid storage layer in fluid communication with said secondary distribution layer, and comprising from about 15 to 100% by weight of said storage layer of absorbent gelling material and from 0 to about 85% by weight of said storage layer of a carrier for said absorbent gelling material;

(4) a fibrous layer adjacent said storage layer and comprising a mixture of hydrophilic cellulosic fibers and thermoplastic material bonding said fibers together into a thermally bonded matrix;

(D) a fluid impervious backsheet.

45. The pad of claim 44 wherein said topsheet is an apertured formed film topsheet.

46. The pad of claim 44 having:

(1) a compressive force value in the dry state of about 300 g or less;

(2) an absolute recovery from compression value in the wet state of at least about 48 mm; and

(3) a relative recovery from compression value in the wet state of at least about 65% of the initial pad width.

47. The pad of claim 46 having:

(1) a compressive force value in the dry state in the range of from about 100 to about 200 g;

(2) an absolute recovery from compression value in the wet state of from about 55 to about 65 mm; and

(3) a relative recovery from compression value in the wet state of from about 75 to about 85% of the initial pad width.

48. The pad of claim 44 wherein said thermally bonded matrices of each of said layers (B) and (C)(2) provide vertical wicking of from about 2 to about 4 cm of artificial menstrual fluid.

49. The pad of claim 48 wherein said layers (B) and (C)(2) have a wet density in the range of from about 0.03 to about 0.07 g/cc.

50. The pad of claim 49 wherein said layer (C)(1) has a wet density in the range of from about 0.10 to about 0.15 g/cc and wherein said storage layer (C)(3) comprises absorbent gelling material in an amount of from about 80 to about 150 gsm.

51. The pad of claim 48 wherein said thermally bonded matrix of said layer (A) provides vertical wicking of from about 11 to about 16 cm of artificial menstrual fluid.

52. The pad of claim 51 wherein said thermally bonded matrices of each of said layers (B), (C)(1) (C)(2) and (C)(4) are formed from a mixture comprising from about 10 to 95% wood pulp fibers and from about 5 to about 90% thermoplastic binder fibers.

53. The pad of claim 52 wherein said thermally bonded matrix of said layer (C)(4) is formed from a mixture comprising from about 85 to about 90% wood pulp fibers and from about 5 to about 10% thermoplastic bicomponent binder fibers.

54. The pad of claim 52 wherein said thermally bonded matrix of said layer (C)(1) is formed from a mixture having a basis weight of from about 50 to about 200 gsm and comprising from about 80 to about 90% wood pulp fibers and from about 10 to about 20% thermoplastic bicomponent binder fibers.

55. The pad of claim 52 wherein said thermally bonded matrix of said layer (C)(1) is formed from a mixture having a basis weight of from about 80 to about 180 gsm and comprising from about 85 to about 95% wood pulp fibers and from about 5 to about 15% thermoplastic binder fibers.

56. The pad of claim 52 wherein said thermally bonded matrices of each of said layers (B), (C)(1) (C)(2) and (C)(4) are formed from a mixture comprising from about 55 to about 90% wood pulp fibers and from about 10 to about 45% thermoplastic binder fibers.

57. The pad of claim 56 wherein said thermally bonded matrices of each of said layers (B) and (C)(2) are formed from a mixture having a basis weight of from about 40 to about 60 gsm. and comprising from about 45 to about 90% wood pulp fibers;

up to about 30% hydrophilic nonbonding thermoplastic fibers, and from about 5 to about 50% thermoplastic bicomponent binder fibers.

58. A catamenial pad capable of acquiring, distributing and storing aqueous body fluids, which comprises:

(A) a fluid pervious topsheet selected from the group consisting of apertured formed film topsheets and high loft nonwoven topsheets;

(B). a fluid acquisition layer adjacent said topsheet, said acquisition layer comprising a mixture of hydrophilic cellulosic fibers and thermoplastic material bonding said fibers together into a thermally bonded matrix;

(C) an absorbent core in fluid communication with said fluid acquisition layer and having;

(1) a primary fluid distribution layer comprising a mixture of hydrophilic cellulosic fibers and thermoplastic material bonding said fibers together into a thermally bonded matrix;

(2) a secondary fluid distribution layer in fluid communication with, and which can acquire aqueous body fluids from, said primary distribution layer, said secondary distribution layer comprising a mixture of hydrophilic cellulosic fibers and thermoplastic material bonding said fibers together into a thermally bonded matrix;

(3) a fluid storage layer in fluid communication with said secondary distribution layer, and comprising from about 15 to 100% by weight of said storage layer of absorbent gelling material and from 0 to about 85% by weight of said storage layer of a carrier for said absorbent gelling material;

(D) a fluid impervious backsheet;

(E) wherein the pad has;

(1) a compressive force value in the dry state of about 300 g or less;

(2) an absolute recovery from compression value in the wet state of at least about 48 mm; and

(3) a relative recovery from compression value in the wet state of at least about 65% of the initial pad width.

59. The pad of claim 58 having:

(1) a compressive force value in the dry state in the range of from about 50 to about 300 g;

(2) an absolute recovery from compression value in the wet state of from about 48 to about 70 mm; and

(3) a relative recovery from compression value in the wet state of from about 65 to about 90% of the initial pad width.

60. The pad of claim 58 having:

(1) a compressive force value in the dry state of about 200 g or less;

(2) an absolute recovery from compression value in the wet state of at least about 55 mm; and

(3) a relative recovery from compression value in the wet state of at least about 75% of the initial pad width.

61. The pad of claim 60 having:

(1) a compressive force value in the dry state in the range of from about 100 to about 200 g;

(2) an absolute recovery from compression value in the wet state of from about 55 to about 65 mm; and

(3) a relative recovery from compression value in the wet state of from about 75 to about 85% of the initial pad width.

62. The absorbent structure of claim 61 which further comprises a fibrous layer (C)(4) adjacent said storage layer (C)(3) and comprising a mixture of hydrophilic cellulosic fibers and thermoplastic material bonding said fibers together into a thermally bonded matrix.

63. The pad of claim 62 wherein said thermally bonded matrices of each of said layers (B), (C)(1) (C)(2) and (C)(4) are formed from a mixture comprising from about 55 to about 90% wood pulp fibers and from about 10 to about 45% thermoplastic binder fibers.

64. The pad of claim 63 wherein said thermally bonded matrices of each of said layers (B), (C)(2) and (C)(4) are formed from a mixture having a basis weight of from about 40 to about 60 gsm. and comprising from about 45 to about 90% wood pulp fibers;

up to about 30% hydrophilic nonbonding thermoplastic fibers, and from about 5 to about 50% thermoplastic bicomponent binder fibers.

65. The pad of claim 63 wherein said thermally bonded matrix of said layer (C)(4) is formed from a mixture comprising from about 85 to about 90% wood pulp fibers and from about 5 to about 10% thermoplastic bicomponent binder fibers.

66. The pad of claim 63 wherein said thermally bonded matrix of said layer (C)(1) is formed from a mixture having a basis weight of from about 150 to about 200 gsm and comprising from about 80 to about 90% wood pulp fibers and from about 10 to about 20% thermoplastic bicomponent binder fibers.

67. The pad of claim 63 wherein said thermally bonded matrix of said layer (C)(1) is formed from a mixture having a basis weight of from about 160 to about 180 gsm and comprising from about 85 to about 95% wood pulp fibers and from about 5 to about 15% thermoplastic binder fibers.