Crosslinked Polyurethane-Coated PET Fabric for Ship Traction Sails
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing paraglider sails are not suitable for maritime use due to high stresses and environmental conditions, requiring a fabric that maintains porosity and mechanical properties while being lightweight enough to support ships or vessels.
Innovation Solution
A fabric composed of multifilament continuous warp yarns and weft yarns made of poly(ethylene terephthalate) coated with crosslinked polyurethane, providing stable porosity and mechanical strength under maritime conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If paraglider sail fabrics are used for pulling ships, then the fabric must provide sufficient mechanical strength, but the fabric becomes too heavy to remain airborne
Solution Approach 1:
The patent uses a composite structure combining a polyethylene terephthalate (PET) textile base fabric with a polyurethane (PU) coating layer. This composite material provides the necessary mechanical strength for maritime applications while maintaining low weight for airborne operation. The PET textile provides tensile strength and structural integrity, while the PU coating adds durability and environmental resistance without significant weight increase.
Solution Approach 2:
The patent optimizes specific parameters including the textile coverage rate (TC) between 2.0 and 4.0, PU coating thickness between 10-50 micrometers, and PU elastomer modulus between 1-5 MPa. These parameter adjustments allow the fabric to achieve the required strength-to-weight ratio for ship towing applications while maintaining airborne capability.
2Weight of moving object
If the fabric is made lighter for airborne use, then it can remain in the air, but it loses mechanical strength and stability under maritime conditions
Solution Approach 1:
The patent applies a thin PU coating film (10-50 micrometers) on the PET textile base. This thin flexible film provides environmental protection against saltwater, UV radiation, and moisture while adding minimal weight. The coating forms a protective barrier that enhances reliability in maritime conditions without compromising the lightweight characteristic needed for airborne operation.
Solution Approach 2:
The combination of PET textile and PU coating creates a composite material where each component contributes specific properties: PET provides structural strength and lightweight characteristic, while PU provides environmental resistance and durability. This composite structure achieves both lightweight and high reliability requirements simultaneously.
3Weight of moving object
If the fabric porosity is increased to reduce weight, then the fabric becomes lighter, but it loses mechanical strength and structural integrity
Solution Approach 1:
The patent utilizes a PET textile base fabric with controlled porosity that allows lightweight construction while maintaining structural integrity. The textile structure is designed with specific coverage rate (TC 2.0-4.0) that creates an optimized pore structure, providing both weight reduction and mechanical strength through the interconnected fiber network.
Solution Approach 2:
The PU coating layer reinforces the porous PET textile structure, distributing loads across the fabric and preventing failure at weak points. The composite structure allows the textile to maintain its porous lightweight structure while the coating provides additional strength, resolving the contradiction between porosity and mechanical strength.
4Stability of the object's composition
If a rigid coating is applied to maintain porosity stability, then porosity remains stable under stress, but the fabric loses flexibility and elongation capacity
Solution Approach 1:
The patent specifies a PU elastomer modulus between 1-5 MPa, which is sufficiently low to allow the coating to flex and elongate with the fabric under dynamic loads. This parameter selection ensures the coating maintains porosity stability through consistent application thickness while preserving the fabric's flexibility and adaptability to varying wind and sea conditions.
Solution Approach 2:
The patent employs a flexible PU coating rather than a rigid coating. The flexible nature of the PU elastomer allows the coating to deform with the fabric during dynamic operation, maintaining porosity stability through uniform stress distribution while preserving the fabric's elasticity and movement capability needed for airborne traction.
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 fabric maintains porosity and mechanical strength, allowing aerial traction structures to support ships or vessels effectively while being lightweight and durable.
Implementation Method 1
a fabric, in particular for a ship traction structure, formed from continuous warp yarns and weft yarns and coated on one or both of its two surfaces with a polyurethane (PU)
Data Source
AI summary
A fabric for a ship traction structure is provided that is formed from multifilament continuous warp yarns and weft yarns and coated on one or both of its two surfaces with a polyurethane (PU), the fabric having a coverage rate TC of between 1.8 and 4, the yarns being made of poly(ethylene terephthalate) (PET) and a density of between 20 and 50 yarns/cm, in terms of warp and weft density, the polyurethane (PU) being crosslinked and polyether-, polyester-, or polycarbonate-based. The crosslinked PU is derived from crosslinking a single-component polyurethane having a modulus at 100% elongation less than or equal to 5 MPa according to standard DIN 53504, implemented in organic solvent phase and a crosslinking agent. A ship traction structure of the paraglider sail type made with such a fabric is also provided.