Refastenable Seams Shear Strength Control for Disposable Absorbent Pants
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Disposable absorbent pants with refastenable seams often suffer irreparable damage due to shear stress, either tearing at the seams or delamination, making them difficult to unfasten and leading to premature replacement.
Innovation Solution
The design incorporates refastenable seams with controlled shear separation strength, ensuring they unfasten before causing damage to the garment, with a shear separation strength ratio between 0.01 and 0.99 compared to the tensile strength of the outer cover, and greater than the peel separation strength, to prevent delamination and detachment of fastening components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If refastenable seams are made with strong bonding to ensure they remain fastened during wear, then the reliability of the fastening is improved, but the garment may suffer irreparable damage such as tearing or delamination when shear force is applied to unfasten them
Solution Approach 1:
The patent applies parameter changes by controlling the shear separation strength of the refastenable seam to be within a specific range (0.01 to 0.99 times the tensile strength of the outer cover). This quantitative parameter control ensures the seam is strong enough to remain fastened during normal wear but weak enough to unfasten before causing irreparable damage to the garment structure.
2Stability of the object's composition
If refastenable seams are made with high shear strength to prevent accidental unfastening, then the stability of the fastening is improved, but the ease of operation for intentional unfastening deteriorates
Solution Approach 1:
The patent resolves this contradiction by establishing an optimal parameter range for shear separation strength. The seam strength is calibrated to be sufficient for normal wear stability but controlled to allow easy unfastening when needed, achieving both stability and operational ease within the specified strength ratio range.
3Reliability
If hook and loop fasteners are used that increase in shear strength during wear and tear, then the fastening reliability is improved over time, but the difficulty of unfastening increases making the garment harder to open for checking
Solution Approach 1:
The patent addresses this issue by controlling the maximum shear separation strength parameter of the refastenable seam to remain within the specified range even after wear and tear. This ensures that while the fastening maintains reliability during use, it does not become excessively difficult to unfasten for checking, as the strength increase is bounded by the designed parameter range.
4Ease of operation
If refastenable seams are made with low shear strength to facilitate easy unfastening, then the ease of operation is improved, but the reliability of the fastening during normal wear deteriorates
Solution Approach 1:
The patent resolves this contradiction by establishing a minimum threshold for shear separation strength within the specified parameter range. The seam strength is controlled to be high enough to maintain fastening reliability during normal wear but not so high as to prevent easy unfastening when needed, achieving a balanced operational state through parameter optimization.
Data Source
AI summary
A disposable absorbent pant having refastenable seams that minimize the product's potential for tearing when forces are applied to separate the refastenable seams. More particularly, the refastenable seams have a shear separation strength that is less than a tensile or tear strength of the outer cover and/or side panels. Also, the bonding strength between a fastening component and the portion of the chassis to which the fastening component is bonded may be greater than the shear separation strength of the refastenable seams. Additionally, the shear separation strength of the refastenable seams may be greater than the peel separation strength of the refastenable seams to enable easy unfastening of the garment through the application of peel forces.