Multilayer absorbent structure

• US 4,360,015 A
• Filed: 05/14/1981
• Issued: 11/23/1982
• Est. Priority Date: 05/14/1981
• Status: Expired due to Fees

• Current Assignee: The Hartford Financial Services Group, Inc.
• Original Assignee: The Hartford Financial Services Group, Inc.
• Inventors: Mayer, Nathan
• Primary Examiner(s): Rosenbaum, C. Fred
• Application Number:
  US06/263,685
• Time in Patent Office: 558 Days
• Field of Search: 128/284, 128/287, 128/290 R, 128/296, 128/156, 128/155
• US Class Current: 602/47
• CPC Class Codes: A61F 13/01029 made of multiple layers
• CPC Class Codes: A61F 13/01038 Flexibility, stretchability or elasticity
• CPC Class Codes: A61F 13/51121 characterised by the material
• CPC Class Codes: A61F 13/512 characterised by its apertures, e.g. perforations
• CPC Class Codes: A61F 13/534 having an inhomogeneous composition through the thickness of the pad A61F13/538, A61F13/539 take precedence; homogeneous cores with tissue wrapping A61F13/53
• CPC Class Codes: A61F 13/537 characterised by a layer facilitating or inhibiting flow in one direction or plane, e.g. a wicking layer A61F13/538 takes precedence
• 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 2013/00157 for burns or skin transplants A61F2013/00187 takes precedence; not adhering to the wound A61F2013/00217
• CPC Class Codes: A61F 2013/00255 with pores
• CPC Class Codes: A61F 2013/00519 for treating burn
• CPC Class Codes: A61F 2013/00604 Multilayer
• CPC Class Codes: A61F 2013/0074 containing foams
• CPC Class Codes: A61F 2013/00744 containing non-woven
• CPC Class Codes: A61F 2013/00863 with pores
• CPC Class Codes: A61F 2013/15821 characterized by the apparatus for manufacturing
• CPC Class Codes: A61F 2013/51409 being a film
• CPC Class Codes: A61F 2013/530802 characterized by the foam or sponge other than superabsorbent A61F2013/530649 takes precedence
• CPC Class Codes: A61F 2013/53445 from several sheets
• CPC Class Codes: A61F 2013/53782 with holes
• CPC Class Codes: A61F 2013/53908 with adhesive
• CPC Class Codes: A61L 15/24 : Macromolecular compounds obtained by reactions only involving carbon-to-carbon unsaturated bonds; Derivatives thereof A61L15/225 takes precedence
• CPC Class Codes: A61L 15/425 : Porous materials, e.g. foams or sponges
• CPC Class Codes: B32B 17/02 : in the form of fibres or filaments
• CPC Class Codes: B32B 2305/026 : Porous
• CPC Class Codes: B32B 2323/04 : Polyethylene
• CPC Class Codes: B32B 2375/00 : Polyureas; Polyurethanes
• CPC Class Codes: B32B 5/022 : Non-woven fabric
• CPC Class Codes: B32B 7/12 : using interposed adhesives or interposed materials with bonding properties
• CPC Class Codes: C08L 23/02 : not modified by chemical after-treatment

Abstract

A multilayer absorbent bandage and process for making the same having two absorbent layers separated by a grid material and covered on one side by an exterior layer which contacts the wound surface and on the other side by a moisture resistant barrier. The bandage is designed to maintain its structural integrity while being capable of absorbing large amounts of fluid.

Claims

1. A multilayer absorbent structure, which comprises:

(a) an exterior layer which contacts the wound surface;

(b) an absorbent cellulosic layer joined to the exterior layer;

(c) a nonabsorbent grid material which is joined on one side to the absorbent cellulosic layer and on the other side to a flexible absorbent member;

(d) said flexible absorbent member formed of a flexible sheet of sponge material containing a web of absorbent fibers disposed on the flexible sheet and extending into the flexible sheet without extending through the flexible sheet;

(e) a moisture resistant barrier layer making an outer layer which is joined to the lower side of the sponge material portion of the flexible absorbent member.

2. The absorbent structure of claim 1 wherein the exterior layer is a porous non-woven web material.

3. The absorbent structure of claim 1 wherein the exterior layer is a perforated thermoplastic material.

4. The absorbent structure of claim 1 wherein the absorbent cellulosic layer is composed of a plurality of sheets of absorbent, porous, fibrous tissue.

5. The absorbent structure of claim 1 wherein the absorbent cellulosic layer is a non-woven, loosely spaced cellulosic material.

6. The absorbent structure of claim 1, wherein the grid material has apertures between 1 and 20 openings per inch.

7. The absorbent structure of claim 1 wherein an adhesive is applied to the grid material for bonding together the absorbent cellulosic layer and the flexible absorbent member.

8. The absorbent structure of claim 1 wherein the flexible absorbent structure contains a web of rayon needle-punched into the sponge material.

9. The absorbent structure of claim 8 wherein the sponge structure is a polyurethane foam having a thickness of about 1/4 to 3/4 inch.

10. The absorbent structure of claim 1 wherein the moisture resistant barrier layer is a film of polyethylene.

11. A multilayer absorbent structure, which comprises:

(a) an exterior layer which contacts the wound surface selected from a porous non-woven web material or a perforated thermoplastic material;

(b) a non-woven, loosely spaced absorbent cellulosic layer joined to the exterior layer;

(c) a nonabsorbent grid material having between 1 and 20 openings per inch and which is joined on one side to the absorbent cellulosic layers and on the other side to a flexible absorbent member;

(d) said flexible absorbent member formed of a flexible sheet of polyurethane foam containing a web of rayon fibers disposed on the foam and extending into but not through the foam; and

(e) a moisture resistant barrier layer making an outer layer which is joined to the lower side of the sponge material portion of the flexible absorbent member.

12. A process for preparing a multilayer absorbent structure which comprises:

(a) bonding two absorbent layers to a grid material having between 1 and 20 openings per inch so that the grid material separates the two absorbent layers, said absorbent layers comprising an absorbent cellulosic layer and a flexible absorbent material formed of a flexible sheet of sponge material covered with a web of needle pressed absorbent fibers;

(b) bonding an exterior layer which is capable of transmitting fluid to the absorbent cellulosic layer; and

(c) bonding a moisture resistant barrier to the sponge material of the flexible absorbent material.

13. The process of claim 12 wherein bonding is achieved by applying an adhesive to the exterior layer and moisture resistant barrier layer in given pattern so that when these layers are bonded to the exterior surfaces of the absorbent layers only a portion of the surface of the absorbent layers is bonded, thereby leaving a sufficient amount of area available for fluid transfer.

14. The process of claim 12 wherein an adhesive is applied to the grid material by passing the grid material over an adhesive coated roll which because of the voids in the grid, coats the entire surface of the grid material.

15. The process of claim 12 wherein the five layers are pressed together in a single step.

16. The process of claim 15 wherein pressing is achieved at 12 to 60 pounds pressure per lineal inch and at temperatures from about 180°

to 300°

F.