Soft Nonwoven Layer With Calendering Bonds For Absorbent Articles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current methods for enhancing the softness of nonwoven web materials in disposable absorbent articles face challenges in precisely measuring and achieving softness, as it is a subjective and complex attribute influenced by tactile, auditory, and visual signals, and often come at the cost of reducing mechanical properties or increasing production costs.
Innovation Solution
A nonwoven material comprising fibers made of a composition including a first polyolefin, a second elastomeric polyolefin, and a softness enhancer additive, with calendering bonds having a specific aspect ratio, is used in absorbent articles to enhance softness while maintaining or improving tensile strength.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If conventional methods are used to enhance softness of nonwoven web materials, then softness perception is improved, but tensile strength deteriorates
Solution Approach 1:
The patent changes the physical and chemical parameters of the nonwoven material by incorporating specific polyolefin elastomers (5-20% by weight) and softness enhancer additives (0.1-5% by weight), along with creating calendering bonds with specific aspect ratios (2.5:1 or higher). These parameter changes achieve enhanced softness perception while maintaining tensile strength through optimized material composition and bonding structure.
Solution Approach 2:
The patent creates a composite material system combining multiple polyolefin types (first polyolefin, second polyolefin elastomer) with softness enhancer additives. This composite approach allows the material to exhibit both softness characteristics from the elastomer and additive components, while maintaining structural strength through the synergistic combination of different polymer phases and calibrated bonding patterns.
2Ease of manufacture
If basis weight is increased to enhance loft and softness perception, then visual and tactile softness signals are improved, but production cost increases
Solution Approach 1:
Instead of increasing basis weight, the patent changes the compositional parameters by incorporating polyolefin elastomers (5-20% by weight) and softness enhancer additives (0.1-5% by weight). These compositional changes enhance softness perception through modified fiber properties and surface characteristics without requiring additional material quantity, thereby avoiding increased production costs associated with higher basis weight.
Solution Approach 2:
The patent applies softness enhancement locally through targeted incorporation of elastomeric components and softness enhancer additives within the nonwoven structure. The calendering bonds with high aspect ratios (2.5:1 or higher) create localized soft zones that enhance perceived softness without requiring uniform increases in overall material quantity across the entire nonwoven web.
3Ease of manufacture
If softness enhancer additives are incorporated into fiber composition, then perceived softness is enhanced, but manufacturing complexity increases
Solution Approach 1:
The patent incorporates softness enhancer additives (0.1-5% by weight) into the fiber composition during the existing extrusion and forming processes. By integrating the additive incorporation into standard manufacturing operations rather than requiring separate treatment steps, the perceived softness is enhanced without proportionally increasing manufacturing complexity. The calendering process with controlled bond aspect ratios further enhances softness using existing equipment capabilities.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The solution effectively enhances the perceived softness of absorbent articles while maintaining or improving tensile strength, thus balancing cost and performance, and is applicable across various basis weights to achieve a dramatic visual 3-dimensional appearance and suitable mechanical properties.
Implementation Method 1
a composition comprising a first polyolefin, a second polyolefin that is an elastomeric polyolefin and different than the first polyolefin, and a softness enhancer additive
Implementation Method 2
The layer of fibers comprises a plurality of calendering bonds, said calendering bonds having a bond shape with a greatest measurable length and a greatest measurable width. The aspect ratio of the greatest measurable length to the greatest measurable width is at least 2.5
Data Source
Figure 1A
Figure 1B
Figure 2A
AI summary
An article having as a component a nonwoven material, which includes a layer of spunbond fibers. The fibers of the nonwoven material are made of a composition that includes a first polyolefin, a second polyolefin that is a propylene copolymer and is different from the first polyolefin and a softness enhancer additive. The layer of fibers also includes a plurality of calendering bonds with an aspect ratio of at least 2.5