Polyurethane Waterproof Membrane with Pre-Coating for Faster Curing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing waterproofing systems for building applications, particularly in roofing, face issues with adhesion, compatibility, and aging, and are affected by environmental conditions, leading to inconsistent performance and longer curing times.
Innovation Solution
A waterproof membrane comprising a support carrier and a cross-linked polyurethane coating composition formed by reacting compounds with hydroxyl groups and polyisocyanate cross-linking agents, which is cured at controlled temperatures to ensure durable and reliable installation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If liquid two-component polyurethane systems are applied and cured under outdoor conditions, then a waterproof barrier is formed, but the curing speed becomes dependent on humidity and temperature resulting in inconsistent curing times
Solution Approach 1:
The patent applies a primer layer containing reactive groups (isocyanate, hydroxyl, or carboxyl groups) to the substrate before applying the polyurethane coating. This preliminary action ensures that the substrate is pre-equipped with reactive groups that will immediately react with the incoming polyurethane components, eliminating the need for the coating to rely solely on environmental conditions for curing initiation. The primer layer acts as a buffer that guarantees consistent curing regardless of outdoor humidity and temperature variations.
2Ease of manufacture
If polyvinylchloride-based waterproofing sheets are used with adhesives, then the sheets can be glued to the support, but the adhesives contain ingredients from different chemical families leading to adhesion problems and reduced resistance to ageing
Solution Approach 1:
The patent uses adhesives that are chemically compatible with both the polyvinylchloride waterproofing sheet and the polyurethane coating layer. Specifically, the adhesive contains reactive groups that can bond with the PVC material while also being compatible with the polyurethane chemistry. This homogeneity in chemical composition across different layers ensures consistent adhesion and maintains resistance to ageing throughout the entire system, eliminating the incompatibility issues that arise from using adhesives from different chemical families.
3Ease of manufacture
If bitumen-based waterproofing sheets are fixed by flame heating, then the sheets can be attached to the roof, but the support sheet must be flameproof adding to material requirements
Solution Approach 1:
The patent replaces the flame heating mechanical system with a chemical bonding system. Instead of using heat and flame to attach the waterproofing sheet, the invention uses chemically reactive adhesives that form strong bonds through chemical reactions. This substitution eliminates the need for flameproof support sheets and specialized flame heating equipment, reducing material requirements and simplifying the overall system while maintaining effective attachment.
4Reliability
If a second polyurethane topcoat layer is applied after the base layer cures, then a complete waterproof system is achieved, but the total installation time is extended due to mandatory drying and curing intervals
Solution Approach 1:
The patent applies a reactive primer layer to the substrate before applying the base polyurethane coating. This primer layer contains reactive groups that immediately begin the curing process upon contact with the polyurethane components, eliminating the need for a separate drying period between the base layer and topcoat layer. The preliminary preparation of the substrate with reactive groups ensures that the entire system cures as an integrated unit, significantly reducing total installation time while maintaining the completeness and reliability of the waterproof system.
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 solution provides a waterproof membrane with improved adhesion, resistance to weather and UV aging, and faster installation, while ensuring consistent performance and reduced curing time, addressing the limitations of prior art systems.
Implementation Method 1
a cross-linked coating composition comprising at least one polyurethane, wherein said polyurethane is obtained from a composition comprising at least one compound having hydroxyl groups, and at least one polyisocyanate cross-linking agent with free isocyanate groups
Implementation Method 2
curing the layer of the coating composition at temperatures in the range of 50° to 160° C.
Data Source
AI summary
The invention relates to a waterproof membrane for building applications comprising at least one support carrier and at least one layer of a cross-linked coating composition comprising at least one polyurethane. The invention also relates to a waterproof membrane comprising at least one support carrier and at least one layer of a cross-linked coating composition comprising at least one polyurethane, an optional pre-coating layer to facilitate the manufacturing process, and to join the support carrier with the cross-linked coating composition in the most optimal and durable manner to achieve good surface appearance and chemical bonding between reinforcing carrier and crosslinked polyurethane coating. The waterproof membrane can be prepared and installed with lower cost in comparison to current flat roof waterproofing systems based on liquid two-component polyurethane systems.