Multi-ply Tissue Macrofolds for Wet Texture Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing paper products, such as tissues and towels, lose surface texture when wet due to fiber relaxation, leading to a flat state, which compromises their absorbency and wiping efficiency.
Innovation Solution
A multi-ply tissue product is created by attaching a ply with macrofolds to a conventional planar ply, forming a wave-like structure with a transversely oriented void, maintaining texture even when wet through the use of macrofolds that extend between attachment points, enhancing surface area and aesthetic appeal.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Shape
If embossing is used to increase surface texture, then surface texture is improved in the dry state, but the texture is lost when wetted due to fiber relaxation
Solution Approach 1:
The patent applies macrofolds - large-scale curved structures with amplitudes of at least 0.5 mm - to create permanent surface texture. These macrofolds maintain their curved shape when wetted, unlike conventional embossing, because they create structural form rather than relying solely on fiber deformation. The curvature is imposed at a scale that resists relaxation upon wetting.
Solution Approach 2:
The invention transitions from two-dimensional surface embossing to three-dimensional macrofolding by creating wave-like structures with significant amplitude and wavelength. This dimensional change from flat surface modification to volumetric folding creates texture that maintains its form when wet, as the three-dimensional structure provides mechanical stability against fiber relaxation.
2Shape
If conventional embossing is used to create surface texture, then aesthetic appearance is improved, but absorbency and wiping efficiency are compromised when wet
Solution Approach 1:
The macrofolds create permanent three-dimensional curved structures that maintain their shape when wetted, providing both aesthetic appeal and functional wiping surfaces. The large-scale curvature (amplitude ≥ 0.5 mm) ensures the texture persists in the wet state, maintaining reliability for wiping applications.
Solution Approach 2:
The invention changes the scale parameters of surface texture from conventional embossing (micrometer-scale) to macrofolding (millimeter-scale amplitude and wavelength). This parameter change creates structures that are large enough to maintain structural integrity when wet, thereby preserving wiping efficiency and absorbency.
3Area of moving object
If a multi-ply structure is created with different ply lengths, then macrofolds and surface area are increased, but manufacturing complexity increases
Solution Approach 1:
The patent segments the tissue product into multiple plies with different machine direction lengths. The first ply has MD length substantially equal to sheet length, while the second ply has MD length at least 200% of sheet length. This segmentation allows the second ply to form macrofolds between attachment points, creating increased surface area through a manageable manufacturing approach.
Solution Approach 2:
By allowing plies to extend beyond the sheet boundaries in the machine direction and forming macrofolds, the invention effectively uses the extra length to create three-dimensional wave structures. This dimensional utilization increases surface area without requiring complex manufacturing equipment, as it leverages the existing multi-ply lamination process.
Data Source
AI summary
The present invention provides multi-ply tissue products having distinctly different first and second outer surfaces or sides. The two-sidedness is generally provided by forming one of the surfaces from a tissue ply having a plurality of macrofolds and the other side from a substantially planar tissue ply. The first ply may be attached to the second ply at longitudinally spaced apart points that define a macrofold therebetween. The length of tissue between the points of attachment may form a wave-like structure having an amplitude and wavelength and having a transversely orientated void that extends from a first edge to a second edge of the tissue. The combination of these elements provides a tissue product that is both aesthetically pleasing and well suited to cleaning due to the large amount of surface area created by the macrofolds.