Liquid-Tight Slide Fastener With Gapped Coating
Solution Overview
Problem
Existing liquid-tight slide fasteners require high accuracy in positioning fastener elements due to through-holes, which can impair watertight properties and attachment strength if misaligned or if core sections are deformed during liquid-tight layer formation.
Innovation Solution
The solution involves forming liquid-tight layers with gaps relative to the core sections on the fastener tapes, allowing for attachment of fastener elements without through-holes, ensuring watertight properties and attachment strength regardless of element position, and using thermoplastic elastomer-based layers to maintain integrity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If through-holes are formed in fastener tapes to attach fastener elements, then attachment strength is improved, but positioning accuracy becomes difficult to control and watertight property may be impaired
Solution Approach 1:
The invention extracts and eliminates the through-holes from the fastener tape structure. Instead of forming holes through the tape to attach fastener elements, the liquid-tight layer is formed with gaps that align with the fastener element positions, allowing attachment without compromising the tape integrity or requiring precise hole alignment.
Solution Approach 2:
The liquid-tight layer is designed with localized gaps at specific positions where fastener elements will be attached, while maintaining liquid-tight coverage in other areas. This local modification provides both attachment functionality and watertight protection without requiring through-holes throughout the tape.
2Reliability
If liquid-tight layers are formed on expanded core sections, then watertight property is improved, but core sections may be deformed during layer formation
Solution Approach 1:
The liquid-tight layer is formed on the fastener tape before the fastener elements are attached. This preliminary formation allows the layer to be applied without the interference of already-attached elements, preventing deformation of core sections while ensuring complete coverage for watertight protection.
Solution Approach 2:
The invention changes the physical state and application parameters of the liquid-tight layer formation process to accommodate the expanded core sections. By controlling the layer formation conditions and material properties, the layer can be applied without exerting excessive pressure or heat that would deform the soft core sections, while still achieving effective watertight coverage.
Data Source
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AI summary
There is provided a liquid-tight slide fastener capable of sufficiently ensuring waterproof property regardless of where fastener elements are formed and capable of sufficiently ensuring attachment strength of the fastener elements to fastener tapes provided with liquid-tight layers. There is also provided a manufacturing method for the liquid-tight slide fastener. The liquid-tight slide fastener including a pair of fastener tapes (20) including a pair of tape members (21), expanded core sections (22) respectively provided on opposing tape edges of the pair of tape members (21), and liquid-tight layers (23) formed on one side of the pair of tape members (21); a pair of fastener element rows (30) respectively provided on the pair of fastener tapes (20) and comprised of a plurality of fastener elements (31); and a slider (40) that causes the pair of fastener element rows (30) to engage/disengage. The liquid-tight layers (23) are formed with gaps to the core sections (22) in a width direction of the fastener tapes (20). The fastener elements (31) are attached to the core sections (22).