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US-12622821-B2 - Absorbent article

US12622821B2US 12622821 B2US12622821 B2US 12622821B2US-12622821-B2

Abstract

A disposable absorbent article having a topsheet, a backsheet, and an absorbent core structure disposed therebetween. The absorbent core structure includes an upper nonwoven layer comprising polymer fibers and having a basis weight of from about 35 to about 85 gsm; a lower nonwoven layer comprising polymer fibers and having a basis weight of from about 10 to about 40 gsm; and an inner core layer disposed between the upper and lower nonwoven layers. The inner core layer comprises from about 50% to about 85% cellulosic fibers, by weight of the inner core layer, and from about 15% to about 50% superabsorbent particles, by weight of the inner core layer. The absorbent core structure has an average density of between about 0.045 g/cm 3 and about 0.15 g/cm 3 . The inner core layer is contained within the nonwoven layers by substantially sealing at least a left and right side region of the upper and lower nonwoven layers.

Inventors

  • Christopher Philip Bewick-Sonntag
  • John David Norcom
  • Shirdish Poondru
  • Matthew Howard Wasson
  • Rong Deng

Assignees

  • THE PROCTER & GAMBLE COMPANY

Dates

Publication Date
20260512
Application Date
20230517

Claims (20)

  1. 1 . A disposable absorbent article comprising: a topsheet; a backsheet; and an absorbent core structure disposed between the topsheet and the backsheet, wherein the absorbent core structure comprises: a. an upper nonwoven layer comprising polymer fibers and having a basis weight of from about 35 gsm to about 85 gsm; b. a lower nonwoven layer comprising polymer fibers and having a basis weight of from about 10 gsm to about 40 gsm; and c. an inner core layer disposed between the upper nonwoven layer and the lower nonwoven layer, wherein the inner core layer comprises from about 50% to about 85% cellulosic fibers, by weight of the inner core layer, and from about 15% to about 50% superabsorbent particles, by weight of the inner core layer, and wherein the absorbent core structure has an average density of between about 0.045 g/cm3 and about 0.15 g/cm3; wherein the inner core layer is contained within the upper nonwoven layer and the lower nonwoven layer by substantially sealing at least a left side region and a right side region of the upper nonwoven layer and the lower nonwoven layer at a perimeter seal; and wherein the absorbent core structure comprises a plurality of structural bond sites, wherein the structural bond sites comprise at least the upper nonwoven layer and the inner core layer throughout the structural bond site.
  2. 2 . The disposable absorbent article of claim 1 , wherein the upper nonwoven layer has a Tensile Stiffness of from about 0.3 N/mm to about 1.6 N/mm as measured according to the CD Cyclic Elongation to 3% Strain Method, and a Strain to Break of greater than 10% as measured according to in the Strain to Break Method.
  3. 3 . The disposable absorbent article of claim 1 , wherein the upper nonwoven layer has a Tensile Stiffness of from about 0.3 N/mm to about 1.6 N/mm as measured according to the CD Cyclic Elongation to 3% Strain Method, and a Strain to Break of from about 10% to about 50% as measured according to the Strain to Break Method.
  4. 4 . The disposable absorbent article of claim 2 , wherein the upper nonwoven layer has a Tensile Stiffness of from about 0.3 N/mm to about 1.0 N/mm as measured according to the CD Cyclic Elongation to 3% Strain Method.
  5. 5 . The disposable absorbent article of claim 1 , wherein the lower nonwoven layer has a Permanent Strain of about 0.005 mm/mm to about 0.013 mm/mm as measured according to the CD Cyclic Elongation to 3% Strain Method.
  6. 6 . The disposable absorbent article of claim 1 , wherein the polymer fibers of the upper nonwoven layer are selected from polyethylene terephthalate, polypropylene, polylactic acid, bicomponent fiber comprising polyethylene/polypropylene or polyethylene/polyethylene terephthalate, and combinations thereof.
  7. 7 . The disposable absorbent article of claim 1 , wherein the polymer fibers of the lower nonwoven layer are selected from polyethylene terephthalate, polypropylene, polylactic acid, bicomponent fiber comprising polyethylene/polypropylene or polyethylene/polyethylene terephthalate, and combinations thereof.
  8. 8 . The disposable absorbent article of claim 1 , wherein the polymer fibers of the upper nonwoven layer have a fiber length of from about 10 mm to about 100 mm.
  9. 9 . The disposable absorbent article of claim 1 , wherein the polymer fibers of the upper nonwoven layer have a fiber diameter of from about 2.0 Dtex to about 10 Dtex, and the polymer fibers of the lower nonwoven layer a fiber diameter of from about 1.7 Dtex to about 5 Dtex.
  10. 10 . A disposable absorbent article comprising: a topsheet; a backsheet; and an absorbent core structure disposed between the topsheet and the backsheet, wherein the absorbent core structure has a front, middle, and back region and comprises: a. an upper nonwoven layer comprising polymer fibers and having a basis weight of from about 35 gsm to about 85 gsm; b. a lower nonwoven layer comprising polymer fibers and having a basis weight of from about 10 gsm to about 40 gsm; and c. an inner core layer disposed between the upper nonwoven layer and the lower nonwoven layer, wherein the inner core layer comprises a mixture of cellulosic fibers and superabsorbent particles; wherein the absorbent core structure comprises a plurality of structural bond sites; wherein the structural bond sites comprise at least the upper nonwoven layer and the inner core layer throughout the structural bond site, wherein the structural bond sites have a bond area of from about 2 mm 2 to about 5 mm 2 ; and wherein the total structural bond area of the absorbent core structure is from about 0.75% to about 4.5% of the absorbent core structure as measured according to the Structural Bond Sites Pattern Spacing and Area Measurement Method.
  11. 11 . The disposable absorbent article of claim 10 , wherein the average distance between the structural bond sites is from about 10 mm to about 32 mm as measured according to the Structural Bond Sites Pattern Spacing and Area Measurement Method.
  12. 12 . The disposable absorbent article of claim 10 , wherein the inner core layer has an average density of between 0.045 g/cm 3 and 0.15 g/cm 3 .
  13. 13 . The disposable absorbent article of claim 10 , wherein the inner core layer is contained within the upper nonwoven layer and the lower nonwoven layer by substantially sealing at least a left side region and a right side region of the upper nonwoven layer and the lower nonwoven layer at a perimeter seal.
  14. 14 . The disposable absorbent article of claim 10 , wherein the upper nonwoven layer and the lower nonwoven layer are closer together in the Z direction at the structural bond sites but are not melted together.
  15. 15 . The disposable absorbent article of claim 10 , wherein the absorbent article has a Dry Caliper between about 2.0 mm and about 6.0 mm as measured according to the Wet and Dry CD and MD 3-Point Method.
  16. 16 . The disposable absorbent article of claim 10 , wherein the polymer fibers of the upper nonwoven layer and the polymer fibers of the lower nonwoven layer are different.
  17. 17 . The disposable absorbent article of claim 10 , wherein the polymer fibers of the upper nonwoven layer and the polymer fibers of the lower nonwoven layer are the same.
  18. 18 . The disposable absorbent article of claim 10 , wherein the polymer fibers of the upper nonwoven layer comprise from about 70% to about 100% synthetic fibers, and from about 0% to about 40% regenerated cellulosic fibers comprising rayon.
  19. 19 . The disposable absorbent article of claim 10 , wherein the inner core layer comprises from about 55% to about 80% cellulosic fibers, by weight of the inner core layer, and from about 25% to about 35% superabsorbent particles, by weight of the inner core layer.
  20. 20 . The disposable absorbent article of claim 1 , wherein the upper nonwoven layer and the inner core layer are intermingled within the structural bond sites.

Description

CROSS REFERENCE TO RELATED APPLICATIONS This application claims the benefit of U.S. Provisional Application No. 63/345,582, filed May 25, 2022, and U.S. Provisional Application No. 63/413,634, filed Oct. 6, 2022, and U.S. Provisional Application No. 63/480,335, filed Jan. 18, 2023, the entire disclosures of which are fully incorporated by reference herein. FIELD OF THE INVENTION The present invention pertains to an absorbent article with conforming features as well as improved resilient structures. BACKGROUND OF THE INVENTION Absorbent articles are widely used among consumers, e.g., diapers, training pants, feminine pads, adult incontinence pads, etc. Generally, absorbent articles such as these comprise a topsheet and a backsheet, with an absorbent core structure disposed therebetween. Historically, absorbent core structures for menstrual pad applications utilize cellulose fibers in various ways to manage the complex and varied rheological properties of menstrual fluid and vaginal discharge. The first approach included cellulose (also known as “fluff” or “pulp”) based thick absorbent cores that can be stiff, bulky, and suffer from structural collapse due to the short fiber lengths of cellulose (<2.5 mm), particularly when loaded with fluid due to cellulose fiber softening when wet. Over time, these thick cellulose rich absorbent cores have been made thinner with the inclusion of absorbent polymer materials, such as absorbent gelling material (“AGM”), to further boost their absorption properties. However, these absorbent core structures are less mechanically strong and even less able to retain their shape, particularly when loaded with liquid exudate. These absorbent core structures can form cracks and tears while in-use and bunch (a permanent deformed shape). These thinner structures tend to be even more densified (thus stiffer) and are often wrapped in a simple cellulose tissue or thin nonwoven layer to keep the AGM inside and reduce core tearing and undesirable bunching while in use. Other approaches combine these wrapped cellulose and AGM cores with an additional fluid acquisition-distribution layer (above the fluid storage core) to further improve the performance of these simple wrapped cores. This additional acquisition-distribution layer further serves to improve integrity and to some degree tearing and bunching of the wrapped core. These acquisition-distribution layers, however, are not ideal for complex viscous fluids which need to move over the boundary between these layers. To better facilitate fluid partitioning from the acquisition-distribution system to the fluid storage wrapped cellulose and AGM core, the core can be densified to increase capillarity and the ability to pull fluid effectively from the acquisition-distribution layer above. However, densifying this absorbent system comes at the cost of comfort (stiffness) and the ability of the absorbent core structure and/or absorbent article to readily conform to the wearer's unique anatomical geometry. Another material used in the absorbent core structure includes an airlaid core. Airlaid cores are typically composed of cellulose, AGM, and synthetic binder fibers to enhance wet integrity and often a surface coating of a polymer (such as latex) to reduce dust during product manufacture. Because these materials are manufactured at a separate supplier offline and need to be transported and introduced into a fast-moving production line, they are highly densified and stiff. The densification and synthetic binder fibers provide a higher wet integrity in-use and can help facilitate fluid transport from the acquisition-distribution layer to the airlaid core due to higher capillarity. However, this again can be at the cost of comfort (stiffness) and the ability to readily conform to the wearer's unique anatomical geometry due to high bending stiffness. As such, it would be beneficial to have an improved absorbent article comprising an absorbent core structure which addresses the tradeoff of comfortable conformance and wet resiliency while maintaining good absorbency properties. And, it would be beneficial to provide a method for creating such articles without sacrificing performance properties of the products. SUMMARY OF THE INVENTION Disclosed herein is a disposable absorbent article comprising: a topsheet; a backsheet; and an absorbent core structure disposed between the topsheet and backsheet, wherein the absorbent core structure comprises: an upper nonwoven layer comprising polymer fibers and having a basis weight of from about 35 gsm to about 85 gsm; a lower nonwoven layer comprising polymer fibers and having a basis weight of from about 10 gsm to about 40 gsm; and an inner core layer disposed between the upper nonwoven layer and the lower nonwoven layer, wherein the inner core layer comprises from about 50% to about 85% cellulosic fibers, by weight of the inner core layer, and from about 15% to about 50% superabsorbent particles, by weight of the