Multi-Ply Tissue Through-Air Drying and Embossing to Reduce Stiffness
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
There is a need for tissue products that balance aesthetics with improved physical attributes such as reduced stiffness, increased absorbency, and enhanced wet resiliency, while maintaining a cloth-like appearance.
Innovation Solution
The development of a multi-ply tissue product manufactured through a combination of through-air drying and embossing processes, featuring discrete non-linear embossing patterns that cover a specific percentage of the surface area, resulting in a product with reduced stiffness and improved wet resiliency and absorbency.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If conventional wet-pressing and creping processes are used, then the tissue product achieves traditional strength and smoothness, but the product suffers from high stiffness and reduced bulk
Solution Approach 1:
The patent changes the drying parameter from conventional wet-pressing to through-air drying, which removes water through air circulation rather than mechanical pressing. This parameter change reduces fiber compression and bonding pressure, resulting in lower stiffness while maintaining strength through controlled drying conditions
Solution Approach 2:
Instead of using mechanical pressing to remove water and create bonds, the invention inverts the approach by using air circulation to evaporate water. This inversion eliminates the compressive forces that cause stiffness, allowing the tissue to maintain a softer, more pliable structure while achieving adequate dryness
2Ease of operation
If through-air drying is used, then the web becomes softer and bulkier, but additional embossing converting is required to achieve aesthetic quality
Solution Approach 1:
The patent merges the embossing function into the through-air drying process itself by using patterned drying fabrics or air distribution systems that create aesthetic patterns during drying. This combination eliminates the need for separate embossing converting steps, reducing process complexity while maintaining both softness and aesthetic quality
Solution Approach 2:
The through-air drying system is designed to perform multiple functions simultaneously: it dries the tissue web, creates aesthetic patterns, and maintains softness. This multi-functionality eliminates the need for separate embossing equipment and processes, reducing overall device complexity while achieving multiple desired outcomes
3Shape
If multi-ply embossing is performed to increase bulk and aesthetics, then the product achieves cloth-like appearance, but wet resiliency and absorbency are reduced
Solution Approach 1:
The patent applies embossing patterns selectively rather than uniformly across the entire tissue surface. By creating localized aesthetic features through patterned drying fabrics, the design achieves cloth-like appearance in specific areas while leaving other regions uncompressed and highly absorbent, thereby maintaining wet resiliency and absorbency while providing aesthetic quality
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 embossed multi-ply tissue product achieves a GM Flexural Rigidity less than 600 mg*cm, improved wet resiliency, and enhanced absorbency, providing a more aesthetically pleasing and functional product compared to prior art.
Implementation Method 1
Through-air drying provides a relatively noncompressive method of removing water from the web by passing hot air through the web until it is dry
Implementation Method 2
Embossing elements on the rolls compress and/or deform the web
Data Source
Figure 1A
Figure 1B
Figure 2
AI summary
The present invention provides an embossed multi-ply tissue product that is visually pleasing and has improved physical attributes. For example, the inventive multi-ply tissue products have reduced stiffness, such as a GM Flexural Rigidity less than about 600 mg*cm, improved absorbency, such as a Residual Water (WResidual) value less than about 0.15 g, and improved wet resiliency, such as a wet elastic strain ratio greater than about 32 percent.