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BR-112023000378-B1 - Multilayer fibrous mat, cleaning product, and method for forming a multilayer fibrous mat.

BR112023000378B1BR 112023000378 B1BR112023000378 B1BR 112023000378B1BR-112023000378-B1

Abstract

MULTILAYER FIBROUS MAT, CLEANING PRODUCT, AND METHOD FOR FORMING A MULTILAYER FIBROUS MAT. A process for forming a multilayer fibrous mat with good absorbent capacity and absorbent rate is disclosed. The multilayer fibrous mat can be used as absorbent articles, including cleaning products, such as industrial wipes, food service wipes, and the like. The multilayer fibrous mat includes a first layer and a second layer, as well as a crossing zone, which has capillary pressure between the capillary pressure of the first layer and the capillary pressure of the second layer.

Inventors

  • CHARLES W. COLMAN
  • JOSEPH K. BAKER
  • ANDREW T. BAKER
  • Sridhar Ranganathan
  • Thomas Cavanaugh

Assignees

  • KIMBERLY-CLARK WORLDWIDE, INC

Dates

Publication Date
20260310
Application Date
20210331
Priority Date
20200710

Claims (18)

  1. 1. Multilayer fibrous mat (100), characterized in that it comprises: a first layer (102); a second layer (104) with a capillary pressure lower than the capillary pressure of the first layer (102); and a crossing zone (106) at an interface of the first layer (102) and the second layer (104), wherein the capillary pressure of the crossing zone (106) is between the capillary pressure of the first layer (102) and the capillary pressure of the second layer (104), wherein the crossing zone (106) comprises 5% by weight to 50% by weight of the multilayer fibrous mat.
  2. 2. Multilayer fibrous mat (100), according to claim 1, characterized in that the first layer (102), the second layer or both the first layer and the second layer are a layer formed by foam.
  3. 3. Multilayer fibrous mat (100), according to claim 1 or 2, characterized in that the multilayer fibrous mat is a cleaning product.
  4. 4. Multilayer fibrous mat (100), according to claim 1 or 2, characterized in that the multilayer fibrous mat is an absorbent article.
  5. 5. Multilayer fibrous mat (100), according to any one of claims 1 to 4, characterized in that the first layer formed by foam (102) comprises pulp fibers.
  6. 6. Multilayer fibrous mat (100), according to any one of claims 1 to 5, characterized in that the second layer formed by foam (104) comprises elastomeric polymeric fibers.
  7. 7. Multilayer fibrous mat (100), according to any one of claims 1 to 6, characterized in that the crossing zone (106) includes fibers from the first layer formed by foam (102) and fibers from the second layer formed by foam (104).
  8. 8. Multilayer fibrous mat (100), according to any one of claims 1 to 7, characterized in that the first layer formed by foam (102) has a capillary pressure greater than 33 kilopascals at 0% saturation.
  9. 9. Multilayer fibrous mat (100), according to any one of claims 1 to 8, characterized in that the second layer formed by foam (104) has a capillary pressure of less than 33 kilopascals at 0% saturation.
  10. 10. Multilayer fibrous mat (100), according to any one of claims 1 to 9, characterized in that the cleaning product exhibits an absorbent capacity measured using a Gravimetric Absorbency Testing System (GATS) according to the GATS M/K system test using the Analysis Program Version 4.3.4, of 5.5 grams of fluid per gram of wipe (g/g) or more.
  11. 11. Multilayer fibrous mat (100), according to any one of claims 1 to 10, characterized in that the cleaning product exhibits an absorbent rate measured using a Gravimetric Absorbance Testing System (GATS) according to the M/K test of the GATS system using the Analysis Program Version 4.3.4, of 1.6 ((g/g)*s0.5) or better.
  12. 12. Cleaning product, characterized in that it comprises the multilayer fibrous mat (100), as defined in any one of claims 1 to 11, wherein the second layer formed by foam (104) comprises at least 10% by dry weight of the cleaning product (100).
  13. 13. Method for forming a multilayer fibrous mat (100), characterized in that it comprises: forming a first layer formed of foam (102); and forming a second layer formed of foam (104) having a capillary pressure that is less than the capillary pressure of the first layer formed of foam (102), wherein the first layer formed of foam (102) and the second layer formed of foam (104) are formed using a head box (200); wherein the head box (200) includes at least one lamella (208), and wherein at least one lamella (208) is at least partially retracted from the head box (200).
  14. 14. Method according to claim 13, characterized in that the lamella (208) is retracted to a position sufficient to allow mixing of a portion of fibers from the first formed foam layer and a portion of fibers from the second formed foam layer in the head box (200), forming the first formed foam layer (102), the second formed foam layer (104) and a crossing zone (106).
  15. 15. Method according to claim 13 or 14, characterized in that the fibers of the first formed foam layer (102) and the fibers of the second formed foam layer (104) are supplied to a single headbox (200) as a suspension of fibers of the first formed foam layer and a suspension of fibers of the second formed foam layer.
  16. 16. Method, according to any one of claims 13 to 15, characterized in that at least one of the first formed foam layer (102) and the second formed foam layer (104) is formed using a jet velocity to fabric formation velocity ratio of 0.5:1 to 5:1.
  17. 17. Method, according to any one of claims 13 to 16, characterized in that the crossing zone (106) comprises fibers of the first layer formed by foam and fibers of the second layer formed by foam and comprises 5% by weight to 50% by weight of the cleaning product (100).
  18. 18. Method, according to any one of claims 13 to 17, characterized in that the first layer formed by foam (102) has a capillary pressure at 0% saturation greater than 33 kilopascals and/or the second layer formed by foam (104) has a capillary pressure at 0% saturation less than 33 kilopascals.

Description

FUNDAMENTALS [001] Conventional absorbent articles, including cleaning products, have been made from woven and knitted fabrics. These wipes have been used in all different types of industries, such as for industrial applications, food service applications, medical and healthcare applications, and for general consumer use. Conventional wipes can be reusable if washed properly. Disposable wipes, however, continue to gain popularity and are rapidly replacing many conventional woven or knitted products. Disposable wipes, for example, can offer many advantages. For example, disposable wipes are generally more sterile as they are usually free of debris and contaminants. Washed wipes, for example, may still contain residual debris from previous use and may also accumulate debris during the washing process. In addition, washing woven or knitted wipes can not only generate a large expense but also requires the use of large quantities of water and detergents that must be disposed of properly. Furthermore, in many applications, especially in industrial settings, conventional cleaning cloths are discarded after a single use due to the chemicals and other debris that come into contact with the cloth. [002] However, disposable wipes often suffer from a trade-off between being able to rapidly absorb water or other fluids from a surface and being able to store a large volume of fluid. For example, a wipe may be formed with a structure and fibers suitable for improving capillary pressure (which improves the force that propels the fluid into the wipe to improve the uptake rate), but such structure and fiber selection sacrifice void volume, which determines the wipe's fluid capacity. Furthermore, conventional wipes also suffer from decreased uptake rate with increasing saturation. Thus, as the liquid saturation of the wipe increases, the capillary pressure of the wipe decreases, which in turn decreases the uptake rate. [003] Furthermore, a layered wipe approach was also found to fail to produce a wipe with good collection velocity and good liquid capacity. In particular, as briefly discussed above, wipes or layers of wipes configured for improved collection velocity often exhibit high capillary pressures at low saturation, while wipes configured for high absorbent capacity exhibit very low capillary pressure, even at low saturation. However, surprisingly, when a wipe was formed with a high collection velocity layer adjacent to a high absorbent capacity layer, the interface between the layers was found to exhibit lower capillary pressure than either of the two adjacent layers, resulting in no improvement in performance, even though two separate layers were combined. In particular, it is believed that no improvement in collection velocity or absorbent capacity was observed because the fluid failed to transfer from the high absorbent layer to the high absorbent capacity layer. [004] Therefore, it would be beneficial to provide an absorbent article, such as a wipe, that improves absorbency while maintaining good fluid absorption. Furthermore, it would also be advantageous to provide a method for providing an absorbent article with a cross-zone that has a higher capillary pressure than either of the two adjacent layers. It would also be beneficial to provide a wipe with an increased fluid collection rate. Additionally, it would be advantageous to provide a wipe with improved fluid collection rate, even when the wipe is at least partially saturated. SUMMARY [005] The present disclosure is generally directed to a multi-layered fibrous mat. The multi-layered fibrous mat comprises a first layer, a second layer, and a crossover zone at an interface between the first and second layers. The second layer has a capillary pressure that is lower than the capillary pressure of the first layer, and the crossover zone has a capillary pressure between the capillary pressure of the first layer and the capillary pressure of the second layer. In one aspect, the first layer, the second layer, or both the first and second layers are a foam layer. In addition, in one aspect, the multi-layered fibrous mat is a cleaning product. Alternatively, the multi-layered fibrous mat is an absorbent article. [006] In addition, in one aspect, the first foam layer comprises pulp fibers. In a further aspect, the second foam layer comprises elastomeric polymer fibers. In one aspect, the crossover zone includes fibers from the first foam layer and fibers from the second foam layer. In another aspect, the cleaning product exhibits an absorbent capacity measured using a Gravimetric Absorption Testing System (GATS) according to the GATS test of the M/K system using the Analysis Program Version 4.3.4, of about 5.5 grams of fluid per gram of wipe (g/g) or greater. In yet another aspect, the cleaning product exhibits an absorbent rate measured using a Gravimetric Absorption Testing System (GATS) according to the GATS test of the M/K system using the Analysis Program Version