Absorbent Article Elastic Member Attachment Without Adhesive Hardening
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional disposable diapers face issues with maintaining stretchability in regions inward of side-seal sections due to adhesive hardening affecting elastic members' elasticity and softness, leading to unsuitable product quality.
Innovation Solution
A method and device for manufacturing absorbent articles where elastic members are attached to the first sheet-like member by forming joining portions that sandwich and press the elastic members, ensuring they are attached without adhesives, and overlapping these portions with side-seal sections to prevent loss of stretchability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If adhesive is used to attach elastic members to the first sheet-like member, then the elastic members can be securely attached, but the hardening of the adhesive impairs the elasticity of the elastic members and the softness of the first sheet-like member
Solution Approach 1:
The patent removes the adhesive from the attachment process entirely. Instead of using adhesive to attach the elastic members to the first sheet-like member, the invention uses a mechanical attachment method where the elastic members are sandwiched between the first and second sheet-like members and fixed through thermal bonding or ultrasonic welding of the sheets themselves, thereby eliminating the harmful hardening effect of adhesive while maintaining secure attachment
Solution Approach 2:
The patent replaces the chemical bonding mechanism (adhesive) with a mechanical bonding mechanism. The elastic members are attached through the physical interlocking and thermal/mechanical bonding of the sheet-like members that sandwich them, substituting the chemical system with a mechanical one that preserves elasticity and softness
2Object-generated harmful factors
If elastic members are attached without adhesive by sandwiching between joining portions, then the elasticity and softness are maintained, but there is a risk that end portions of elastic members may move into the inward region laterally
Solution Approach 1:
The patent performs preliminary positioning of the elastic members within the joining portions before the final bonding step. The elastic members are pre-placed and secured in the correct position between the first and second sheet-like members, and then the sheets are thermally or ultrasonically bonded to fix them in place, preventing lateral movement into the inward region
Solution Approach 2:
The patent introduces the second sheet-like member as an intermediary element that sandwiches the elastic members between itself and the first sheet-like member. This intermediary structure provides lateral constraints that prevent the elastic members from moving into the inward region while maintaining their elasticity and proper positioning
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
This approach effectively suppresses the formation of non-stretchable portions inward of side-seal sections, maintaining the intended stretchability and softness of the diaper, resulting in a more suitable product.
Implementation Method 1
the elastic members 35 that have been cut contract in the direction of transport and attempt to expand in the CD direction
Implementation Method 2
the elastic members are substantially sandwiched and pressed in the CD direction by the joining portions j
Data Source
AI summary
An absorbent article having a lateral direction, a vertical direction, and a front-rear direction that are orthogonal to each other is provided. The absorbent article includes: a first sheet-like member; a second sheet-like member; elastic members that are inserted along the lateral direction between a pair of mutually-opposing facing surfaces of the first sheet-like member and that are spaced apart in the vertical direction; joining portions that join the pair of mutually-opposing facing surfaces and that are spaced part in the lateral direction and in the vertical direction; and side-seal sections disposed at each lateral end portion of the absorbent article. The joining portions are formed on two sides of the elastic members in the vertical direction so that the elastic members are sandwiched and pressed between the joining portions on the two sides.