Production method for an absorbent fiber product and corresponding absorbent fiber product

• US 7,758,722 B2
• Filed: 03/09/2004
• Issued: 07/20/2010
• Est. Priority Date: 03/21/2003
• Status: Expired due to Fees

• Current Assignee: Matthews International GmbH (Matthews International Corporation)
• Original Assignee: Saueressig GmbH + Company KG (Matthews International Corporation)
• Inventors: Saueressig, Kilian
• Primary Examiner(s): Hug; Eric
• Assistant Examiner(s): MINSKEY, JACOB T
• Application Number:
  US10/549,765
• Publication Number:
  US 20070160835A1
• Time in Patent Office: 2,324 Days
• Field of Search: 162/192, 162/50, 162/52, 162/63, 162/101, 162/115, 162/123, 162/188
• US Class Current: 162/50
• CPC Class Codes: D21H 25/06 of impregnated or coated paper D21H25/08 takes precedence
• CPC Class Codes: Y10T 428/29 Coated or structually defined flake, particle, cell, strand, strand portion, rod, filament, macroscopic fiber or mass thereof

Abstract

The invention relates to a method for producing an absorbent fiber product, starting with a parent fiber product that comprises fibers that, on the one hand, lie at a statistical distance from one another and, on the other hand, make contact with one another at contact points. The method comprises treating the parent fiber product with a fluid medium in such a way that the fibers are at least partially wetted and the fluid medium is then rapidly evaporated by irradiation, so that the evaporation pressure generated by the evaporating fluid medium has a kinematic effect on the fibers, which increases the distance between them. In this way the risk of inadvertent, in particular, thermal damage to the fibers is eliminated. Furthermore, the intrinsic fiber structure is left unaffected, or is only affected in a controlled manner. This prevents the uncontrolled destruction of the fiber structure and a detrimental effect on the fiber product, for example, to its tear resistance when wet. Instead, the proposed method achieves an expansion of the fiber product on a microscopic scale by increasing the distance between the fibers. In a further embodiment, the intrinsic fiber structure can be controlled and affected in a targeted manner if necessary, by controlling the time period between the wetting of the fibers and the evaporation of the fluid medium.

Claims

1. A method for producing an absorbent fiber product comprising:

treating a parent fiber product with a fluid medium such that fibers of the parent fiber product are at least partially wetted, and

rapidly evaporating the fluid medium by microwave irradiation between the fibers, so that evaporation pressure generated by the evaporating fluid medium has a kinematic effect on the fibers, which increases the distance between the fibers,

wherein power density of the pulsed microwave radiation is between approximately 10³ and approximately 10⁶ W/mm².

2. The method of claim 1, wherein the parent fiber product is exposed to a fluid medium in a form selected from vapor and emulsion.

3. The method of claim 2, wherein the parent fiber product is exposed to at least one of vapor deposition and vapor saturation by the fluid medium in the form of vapor.

4. The method of claim 2, wherein the parent fiber product is one of wetted and saturated by the fluid medium in the form of an emulsion.

5. The method of claim 2, wherein the fibers are homogeneously wetted.

6. The method of claim 1, wherein the fibers contact each other at contact points, and wherein the kinematic effect on the fibers compacts the fibers at the contact points.

7. The method of claim 1, wherein the fibers are subjected to pulsed microwave radiation.

8. The method of claim 1, wherein the microwave radiation comprises wavelengths of approximately 1000 um.

9. The method of claim 1, wherein the microwave radiation comprises wavelengths that are absorbed less by the fibers than by the fluid media.

10. The method of claim 1, wherein exposure time of the pulsed microwave radiation is between approximately 1 μ

s and approximately 1000 ms.

11. The method of claim 1, further comprising adjusting a time period between the wetting of the fibers with the fluid medium and the rapid evaporation of the fluid medium so that diffusion of the fluid medium is directed towards at least one of in between and into the fibers.

12. The method of claim 1, further comprising treating, subsequent to the rapid evaporation of the fluid medium, the parent fiber product with a fluid fixative.

13. A method for producing an absorbent fiber product, comprising contacting a parent fiber product with a fluid medium such that fibers of the parent fiber product are at least partially wetted, and irradiating the fibers, so that the fluid medium between the fibers is rapidly evaporated and an absorbent fiber product is produced that has greater absorbency than the parent fiber product, wherein power density of the irradiation is between approximately 10³ and approximately 10⁶ W/mm².

14. The method of claim 13, wherein the parent fiber product is exposed to a fluid medium in a form selected from vapor and emulsion.

15. The method of claim 13, wherein the fibers are homogeneously wetted.