Stiff Interlayers for Laminated Glass Impact Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional automotive glazing laminates made of soda lime glass with PVB interlayers have limited impact resistance and are prone to breakage from roadside stones and other impacts, while also being heavy and inefficient in terms of sound attenuation and fuel economy.
Innovation Solution
A thin laminated glass structure using chemically strengthened glass sheets with a composite interlayer comprising relatively stiff and soft polymer layers, where the interlayer makes up a significant fraction of the laminate thickness, providing enhanced acoustic damping and rigidity through adjustable Young's modulus and shear modulus properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional PVB interlayers are used in soda lime glass laminates, then the structure achieves low cost and ease of manufacture, but the impact resistance and durability are limited and prone to breakage
Solution Approach 1:
The patent employs a composite interlayer structure consisting of multiple polymer layers with different properties (e.g., stiff PVB layer combined with soft acoustic damping layer). This composite approach enhances impact resistance and durability while maintaining manufacturability, as each layer contributes specific functional properties that collectively improve overall laminate performance.
Solution Approach 2:
The patent modifies the interlayer properties by adjusting the Young's modulus and thickness parameters of different polymer layers. By changing these parameters, the interlayer can provide both structural support and acoustic damping functions, thereby improving reliability without significantly complicating the manufacturing process.
2Strength
If thicker glass laminates are used to improve strength and durability, then the mechanical properties are enhanced, but the weight increases which negatively affects fuel economy in vehicle applications
Solution Approach 1:
The patent uses chemically strengthened glass sheets with controlled thickness parameters (e.g., 0.7mm to 1.5mm per sheet) combined with optimized interlayer thickness and modulus. This parameter optimization allows achieving required strength and durability with thinner glass, thereby reducing weight for fuel economy while maintaining mechanical performance.
Solution Approach 2:
The composite interlayer structure provides enhanced mechanical support that compensates for using thinner glass sheets. The combination of stiff and soft polymer layers creates a composite system that maintains durability while enabling weight reduction through thinner glass components.
3Object-affected harmful factors
If the interlayer thickness is increased to improve acoustic damping, then the sound attenuation is enhanced, but the rigidity and load-bearing capacity may be compromised
Solution Approach 1:
The patent employs a composite interlayer with a multi-layer structure where stiff polymer layers (high Young's modulus) provide rigidity and load-bearing capacity, while soft polymer layers (low Young's modulus) provide acoustic damping. This composite configuration allows simultaneous achievement of both sound attenuation and structural rigidity.
Solution Approach 2:
Different regions of the interlayer are assigned different properties: stiff layers are positioned to provide structural support where needed, while soft layers are positioned to maximize acoustic damping. This local differentiation of material properties enables the interlayer to fulfill multiple functions without compromising overall performance.
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 results in a lightweight, impact-resistant, and sound-dampening glass laminate that meets automotive and architectural specifications, offering improved durability and reduced weight without compromising strength or sound-attenuating properties.
Implementation Method 1
Acoustic damping of a laminated thin glass structure is primarily determined by shear modulus and loss factor of the polymer interlayer
Implementation Method 2
the bending rigidity (load deformation properties) of the laminated thin glass structure will be largely determined by the Young's modulus of the interlayer
Data Source
AI summary
A new laminated glass structure for automotive glazing, architectural window and other applications that includes two sheets of relatively thin, optionally chemically strengthened glass, such as Corning® Gorilla® Glass, with a composite interlayer structure that includes at least one relatively stiff layer having relatively high Young's modulus of 50 MPa or higher and a relatively softer polymer layer having a relatively low Young's modulus of 20 MPa or lower.