Composite Water-Retaining Sheet Material with Synthetic Granules
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing roofing materials face challenges in maintaining quality and adhesion of granules to bitumen over extended periods, often losing protection and appearance due to moisture and light exposure, and failing to meet market demands for alternative colors.
Innovation Solution
A composite water-retaining sheet material utilizing synthetic granules with specific properties such as non-hygroscopic and UV-resistant materials, sharp edges, and varying sizes, embedded in a bituminous layer with a wire gauze for improved adhesion and durability, and manufactured by scattering an over-measure of colored granules onto soft bitumen for full coverage.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional roofing materials with granular surfaces are used, then water drainage is achieved, but granule adhesion to bitumen deteriorates over time (10-20 years)
Solution Approach 1:
The patent changes the chemical composition parameters of the bituminous material by incorporating specific polymers (SBS, SEBS, APP) and modifiers to enhance adhesion properties. The granules are treated with surface coatings containing adhesion promoters that chemically bond to both the granule surface and bitumen, fundamentally altering the interaction parameters at the interface to prevent granule loss over time.
Solution Approach 2:
The patent creates a composite structure where granules are not merely placed on bitumen but are chemically bonded through intermediate adhesion layers. The bituminous material itself is a composite containing multiple polymers and modifiers work together to provide both flexibility and strong bonding, while the granule coating forms a composite interface layer that ensures long-term adhesion stability.
2Adaptability or versatility
If bituminous material is used for roofing, then water retention is achieved, but color options are limited to black
Solution Approach 1:
The patent segments the color function from the base bituminous material by applying colored coatings only to the granule surface layer. This allows the underlying black bitumen to maintain its water retention and adhesion properties while the granule coating provides the color variety. The segmentation enables independent optimization of each layer's function.
Solution Approach 2:
The patent applies different colors to different granules or different regions of the roofing material surface, creating local quality variations. The colored coating is applied locally to the granule surfaces rather than to the entire bituminous sheet, allowing color customization without compromising the overall structural integrity and water retention properties of the bitumen base.
3Object-affected harmful factors
If granules are exposed to moisture and light, then weather protection is provided, but granule properties deteriorate due to moisture absorption and UV exposure
Solution Approach 1:
The patent applies protective coatings to granules before they are exposed to weather conditions. The coating includes UV inhibitors and moisture barriers that are pre-applied to cushion the granules against future environmental damage. This beforehand protection prevents UV degradation and moisture absorption before they can deteriorate the granule's physical and chemical properties.
Solution Approach 2:
The patent introduces an intermediate protective layer between the granule core and the external environment. This coating layer acts as a mediator that blocks harmful UV radiation and prevents moisture penetration while allowing the granule to maintain its protective function. The intermediary layer absorbs or reflects harmful factors before they reach the granule material.
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
Ensures long-term quality and appearance retention with enhanced adhesion and protection, allowing for easy verification of coverage and compliance with color demands, while maintaining structural integrity and weather resistance.
Implementation Method 1
the granules have at least one relatively sharp edge thus achieving a strong adhesion of the granules to the layer of bituminous material
Implementation Method 2
the granules are made out of a non-hygroscopic material. In that way the physical properties and colour of the granules will not be adversely affected by the absorption of moisture
Implementation Method 3
the granules are made out of a UV-radiation proof material, the granules will retain at least almost their original colour during the period of use
Data Source
Figure 1
AI summary
Composite water-retaining sheet material for roofs, comprising a layer of bituminous material, and a fully covering gritty layer provided on a side of the layer of bituminous material, wherein the gritty layer comprises synthetic granules. The material from which the granules have been manufactured has a melt flow index (MFI) between approximately 40 to approximately 60, wherein additionally or alternatively the bituminous material is APAO-, SEBS-, SBS- or APP-modified bituminous material. Method for manufacturing a composite water-retaining sheet material for roofs according to any one of the preceding claims, which method comprises the step of manufacturing the layer of bituminous material, after which, when the layer of bituminous material has not yet solidified, synthetic granules, particularly having a colour that is different from the colour of the layer of bituminous material, are scattered on a side of the layer.