Through-air drying apparatus and methods of manufacture

Patent metadata

Field	Value
Publication number	US-10240292-B2
Application number	US-201616060387-A
Country	US
Kind code	B2
Filing date	Feb 29, 2016
Priority date	Feb 29, 2016
Publication date	Mar 26, 2019
Grant date	Mar 26, 2019

Abstract

Unlike conventional through-air drying processes the instant invention utilizes at least two through-air driers where the first dyer is at least partially encircled by a first through-air drying fabric and the second dyer is at least partially encircled by a second through-air drying fabric. By providing each through-air dryer with its own fabric the overall drying performance may be increased. Additionally, in certain embodiments, the first and second fabrics may be different to optimize both the drying performance and/or tissue product properties.

First claim

What is claimed is:

1. A method of through-air drying a tissue web comprising the steps of transferring a wet tissue web to a first through-air drying fabric and through-air drying the wet web to a consistency of from about 40 to about 80 percent to yield a partially dewatered web; transferring the partially dewatered web to second through-air drying fabric and through-air drying the partially dewatered web to a consistency of from about 60 to about 100 percent.

2. The method of claim 1 wherein the first through-air drying fabric and the second through-air drying fabric are different.

3. The method of claim 1 wherein the first through-air dryer is operated at a temperature from about 300 to about 400° F. and the second through-air dryer is operated at a temperature from about 400 to about 500° F.

4. The method of claim 1 wherein the first through-air drying fabric has surface topography such that there is a z-directional elevation difference of about 0.2 millimeter or greater and the second through-air drying fabric is substantially flat such that the z-directional elevation difference is about 0.2 millimeter or less.

5. The method of claim 1 wherein the first through-air drying fabric comprises at least one substantially MD oriented line element and the second through-air drying fabric comprises at least one substantially MD oriented line element and wherein the substantially MD oriented line element of the first fabric is not aligned with the substantially MD oriented line element of the second fabric.

6. The method of claim 1 wherein the first through-air drying fabric has an air permeability from about 50 to about 400 CFM and the second fabric consists of a through-air drying fabric having an air permeability from about 200 to about 600 CFM.

7. The method of claim 1 further comprising the steps of transferring the partially dried web to an intermediate fabric and transferring the partially dried web from the intermediate fabric to the second through-air drying fabric.

8. The method of claim 1 wherein the partially dewatered web is dried to consistency of at least about 95 percent by the second through-air dryer to yield a dried tissue web and further comprising the steps of winding the dried tissue web into a roll.

9. The method of claim 1 wherein the partially dewatered web is dried to consistency of at least about 60 percent by the second through-air dryer to yield a partially dried tissue web and further comprising the step of adhering the partially dried web to a Yankee dryer and drying the web to a consistency of at least about 95 percent.

10. A method of manufacturing an uncreped through-air dried tissue web comprising the steps of depositing an aqueous furnish comprising cellulosic fiber on a foraminous support to form a wet tissue web; transferring the wet tissue web to a first through-air drying fabric and through-air drying the wet web to a consistency of from about 40 to about 80 percent to yield a partially dewatered web; transferring the partially dewatered web to second through-air drying fabric and through-air drying the partially dewatered web to a consistency greater than about 95 percent.

11. The method of claim 10 wherein the first through-air drying fabric and the second through-air drying fabric are different.

12. The method of claim 10 wherein the first through-air dryer is operated at a temperature from about 300 to about 400° F. and the second through-air dryer is operated at a temperature from about 400 to about 500° F.

13. The method of claim 10 wherein the first through-air drying fabric has surface topography such that there is a z-directional elevation difference of about 0.2 millimeter or greater and the second through-air drying fabric is substantially flat such that the z-directional elevation difference is about 0.2 millimeter or less.

14. The method of claim 10 wherein the first through-air drying fabric comprises at least one substantially MD oriented line element and the second through-air drying fabric comprises at least one substantially MD oriented line element and wherein the substantially MD oriented line element of the first fabric is not aligned with the substantially MD oriented line element of the second fabric.

15. The method of claim 10 wherein the first through-air drying fabric has an air permeability from about 50 to about 400 CFM and the second fabric consists of a through-air drying fabric having an air permeability from about 200 to about 600 CFM.

16. The method of claim 10 further comprising the steps of transferring the partially dried web to an intermediate fabric and transferring the partially dried web from the intermediate fabric to the second through-air drying fabric.

17. A method of manufacturing creped through-air dried tissue web comprising the steps of depositing an aqueous furnish comprising cellulosic fiber on a foraminous support to form a wet tissue web; transferring the wet tissue web to a first through-air drying fabric and through-air drying the wet web to a consistency of from about 40 to about 60 percent to yield a partially dewatered web; transferring the partially dewatered web to second through-air drying fabric and through-air drying the partially dewatered web to a consistency greater than about 60 percent.

18. The method of claim 17 wherein the first through-air drying fabric and the second through-air drying fabric are different.

19. The method of claim 17 wherein the first through-air dryer is operated at a temperature from about 300 to about 400° F. and the second through-air dryer is operated at a temperature from about 400 to about 500° F.

20. The method of claim 17 wherein the first through-air drying fabric has surface topography such that there is a z-directional elevation difference of about 0.2 millimeter or greater and the second through-air drying fabric is substantially flat such that the z-directional elevation difference is about 0.2 millimeter or less.

21. The method of claim 17 wherein the first through-air drying fabric comprises at least one substantially MD oriented line element and the second through-air drying fabric comprises at least one substantially MD oriented line element and wherein the substantially MD oriented line element of the first fabric is not aligned with the substantially MD oriented line element of the second fabric.

22. The method of claim 17 wherein the first through-air drying fabric has an air permeability from about 50 to about 400 CFM and the second fabric consists of a through-air drying fabric having an air permeability from about 200 to about 600 CFM.

Assignees

• Kimberly Clark Co

Inventors

• Hassman Mark John
• Allen Peter John
• Hada Frank Stephen
• Seymour Robert James
• Zanon Richard Allen
• Hansen Richard Mark
• Haiduk Nathan John
• Nelson Samuel August
• Sprangers Daniel Robert
• Baker Paul Timothy

Classifications

• D21H27/002

  Tissue paper; Absorbent paper (D21H21/22, D21H27/02, D21H27/20 take precedence; toilet paper A47K10/00; absorbent pads for physiological fluids A61L15/16; making on paper-making machines D21F11/00) · CPC title

• D21H27/30

  Multi-ply (for surface covering D21H27/18; making on paper-making machines D21F9/00, D21F11/00) · CPC title

• D21F5/182 Primary

  through perforated cylinders · CPC title

• D21H27/007

  relating to absorbency, e.g. amount or rate of water absorption, optionally in combination with other parameters relating to physical or mechanical properties · CPC title

• D21F5/044

  using air hoods over the cylinders · CPC title