Method for making a fibrous structure comprising cellulosic and synthetic fibers

• US 7,354,502 B2
• Filed: 12/18/2003
• Issued: 04/08/2008
• Est. Priority Date: 02/06/2003
• Status: Active Grant

• Current Assignee: The Procter & Gamble Company
• Original Assignee: The Procter & Gamble Company
• Inventors: Trokhan, Paul Dennis, Phan, Dean, Lorenz, Timothy Jude, Polat, Osman
• Primary Examiner(s): FORTUNA, JOSE A
• Application Number:
  US10/740,260
• Publication Number:
  US 20040154763A1
• Time in Patent Office: 1,573 Days
• Field of Search: 162/109, 162111-113, 162/117, 162123-131, 162/146, 162/141, 162/157.1, 162204-207, 162/158, 162/116, 162/211
• US Class Current: 162/146
• CPC Class Codes: D21F 11/006 Making patterned paper
• CPC Class Codes: D21F 11/04 paper or board consisting on two or more layers
• CPC Class Codes: D21H 13/00 Pulp or paper, comprising synthetic cellulose or non-cellulose fibres or web-forming material chemical features in the manufacture of artificial fibres D01F
• CPC Class Codes: D21H 27/38 at least one of the sheets having a fibrous composition differing from that of other sheets
• CPC Class Codes: Y10T 156/1023 Surface deformation only [e.g., embossing]
• CPC Class Codes: Y10T 442/107 Comprising at least two chemically different fibers
• CPC Class Codes: Y10T 442/133 Inorganic fiber-containing scrim
• CPC Class Codes: Y10T 442/14 Including an additional scrim layer
• CPC Class Codes: Y10T 442/153 Including an additional scrim layer
• CPC Class Codes: Y10T 442/159 Including a nonwoven fabric which is not a scrim
• CPC Class Codes: Y10T 442/3707 Woven fabric including a nonwoven fabric layer other than paper
• CPC Class Codes: Y10T 442/668 Separate nonwoven fabric layers comprise chemically different strand or fiber material
• CPC Class Codes: Y10T 442/669 At least one layer of inorganic strand or fiber material and at least one layer of synthetic polymeric strand or fiber material

Abstract

A method for making a fibrous structure, the method comprising the steps of: providing a mixture of synthetic fibers and short cellulosic fibers onto a forming member so as to form one or more layers including the mixture of synthetic fibers and short cellulosic fibers; providing a plurality of long cellulosic fibers onto the mixture of synthetic fibers and short cellulosic fibers so as to form one or more layers including predominantly long cellulosic fibers; and forming a unitary fibrous structure including the one or more layers including the mixture of synthetic fibers and short cellulosic fibers and one or more layers including predominantly long cellulosic fibers.

Claims

1. A method for making a fibrous structure, the method comprising the steps of:

providing a mixture of synthetic fibers and short cellulosic fibers onto a forming member so as to form one or more layers including the mixture of synthetic fibers and short cellulosic fibers;

providing a plurality of long cellulosic fibers onto the mixture of synthetic fibers and short cellulosic fibers so as to form one or more layers including predominantly long cellulosic fibers to form an embryonic web;

forming a unitary fibrous structure including the one or more layers including the mixture of synthetic fibers and short cellulosic fibers and one or more layers including predominantly long cellulosic fibers from the embryonic web;

transferring the unitary fibrous structure to a molding member comprising a pl fluid-permeable areas present in a pattern and a plurality of fluid-impermeable areas; and

redistributing at least some of the synthetic fibers within the unitary fibrous structure by heating the synthetic fibers within the fluid-permeable areas of the molding member resulting in a pattern of micro-regions of synthetic fibers corresponding to the fluid-permeable areas of the molding member.

2. The method of claim 1 wherein the mixture of synthetic fibers and short cellulosic fibers have a fiber length ratio greater than about 1.

3. The method of claim 1, wherein the mixture of synthetic fibers and short cellulosic fibers have a fiber length ratio between about 1 and about 20.

4. The method of claim 1 wherein the mixture of and synthetic fibers and short cellulosic fibers has a coarseness value of less than about 50 mg/100 m.

5. The method of claim 1, further including the step of impressing the fibrous structure between a molding member and a pressing surface to densify portions of the fibrous structure.

6. The method of claim 1 wherein the forming member is moving at a first velocity and the method further includes the steps of:

providing a second member at a second velocity that is less than the first velocity; and

transferring the embryonic web from the forming member to the second member so as to microcontract the embryonic web.

7. The method of claim 1 wherein the unitary fibrous structure is creped, uncreped or embossed.

8. The method of claim 1 including the further step of providing latex to at least a portion of at least one surface of the unitary fibrous structure.

9. A method for making a fibrous structure, the method comprising the steps of:

providing a mixture of synthetic fibers and short cellulosic fibers onto a forming member comprising a plurality of fluid-permeable areas present in a pattern and a plurality of fluid-impermeable areas, wherein the fluid-permeable areas form a pattern of channels, the mixture provided such that at least some of the synthetic fibers are disposed in the channels;

providing a plurality of long cellulosic fibers onto the mixture of synthetic fibers and short cellulosic fibers such that the long cellulosic fibers are disposed adjacent to the synthetic fibers to form an embryonic web;

forming a unitary fibrous structure from the embryonic web;

transferring the unitary fibrous structure to a molding member comprising a plurality of fluid-permeable areas present in a pattern and a plurality of fluid-impermeable areas, wherein the fluid-permeable areas form a pattern of channels; and

redistributing at least some of the synthetic fibers by heating the synthetic fibers within the fluid-permeable areas of the molding member resulting in a pattern of micro-regions of synthetic fibers corresponding to the fluid-permeable areas of the molding member.

10. The method of claim 9 wherein the mixture of synthetic fibers and short cellulosic fibers is provided onto the forming member before the plurality of long cellulosic fibers are provided.

11. The method of claim 9 further including the step of impressing the fibrous structure between the molding member and a pressing surface to densify portions of the fibrous structure.

12. The method of claim 9 wherein the forming member is moving at a first velocity and the method further includes the steps of:

providing a second member at a second velocity that is less than the first velocity; and

transferring the embryonic web from the forming member to the second member so as to microcontract the embryonic web.

13. The method of claim 9 wherein the unitary fibrous structure is creped, uncreped or embossed.

14. The method of claim 9 including the further step of providing latex to at least a portion of at least one surface of the unitary fibrous structure.

15. The method of claim 9 wherein the mixture of synthetic fibers and short cellulosic fibers have a fiber length ratio greater than about 1.

16. The method of claim 9, wherein the mixture of synthetic fibers and short cellulosic fibers have a fiber length ratio between about 1 and about 20.

17. The method of claim 9 wherein the mixture of and synthetic fibers and short cellulosic fibers has a coarseness value of less than about 50 mg/100 m.

18. A method for making a unitary fibrous structure, comprising the steps of:

providing a first aqueous slurry comprising a mixture of synthetic fibers and short cellulosic fibers;

providing a second aqueous slurry comprising a plurality of long cellulosic fibers;

depositing the first and second aqueous slurries onto a forming member comprising a plurality of fluid-permeable areas present in a pattern and a plurality of fluid-impermeable areas, wherein the fluid-permeable areas form a pattern of channels;

partially dewatering the deposited first and second slurries to form an embryonic web comprising the plurality of long cellulosic fibers randomly distributed throughout at least one layer of the fibrous web and the mixture of synthetic fibers and short cellulosic fibers at least partially non-randomly distributed in the channels;

forming a unitary fibrous structure from the embryonic web;

transferring the unitary fibrous structure to a molding member comprising a plurality of fluid permeable areas present in a pattern and a plurality of fluid impermeable areas, wherein the fluid-permeable areas form a pattern of channels;

applying a fluid pressure differential to the unitary fibrous structure disposed on the molding member, thereby molding the unitary fibrous structure according to the pattern of channels, wherein the unitary fibrous structure disposed on the molding member comprises a first plurality of micro-regions corresponding to a plurality of fluid-permeable areas of the molding member and a second plurality of micro-regions corresponding to a plurality of fluid-impermeable areas of the molding member;

redistributing at least some of the synthetic fibers by heating the synthetic fibers within the fluid-permeable areas of the molding member resulting in a pattern of micro-regions of synthetic fibers corresponding to the fluid-permeable areas of molding member; and

transferring the unitary fibrous structure from the molding member to a drying surface.