Insulating Glazing with Segmented Pyrolytic and Sputtered Coatings
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing insulating glazing technologies face challenges in achieving low emissivity and solar factor while maintaining neutral reflection and high visible light transmission, with limitations in improving performance due to the complexity and cost of layer systems, particularly those deposited by cathode sputtering, and the need for more efficient solutions to reduce energy consumption in buildings.
Innovation Solution
The use of a combination of pyrolytic and cathode sputtering layer systems on glass sheets, optimized by polishing the pyrolytic layers to reduce surface roughness and incorporating doped tin oxide and metal layers, along with a high proportion of krypton in the insulating gas, to achieve low thermal coefficients and controlled solar factors.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If layer systems are deposited by cathode sputtering to improve emissivity, then emissivity performance is improved, but device complexity and manufacturing cost increase
Solution Approach 1:
The patent divides the low-emissive coating into two separate glass sheets, each with its own layer system. This segmentation allows each sheet to have a simpler, more cost-effective coating while achieving the same overall emissivity performance as a single complex coating would provide.
Solution Approach 2:
The patent combines two separate glass sheets with layer systems into a single insulating glazing unit. By merging the functions of multiple simpler coatings on different sheets, the system achieves the emissivity performance of a single complex coating while reducing overall complexity and cost.
2Reliability
If more metal and dielectric layers are added to improve emissivity, then emissivity performance is improved, but manufacturing cost increases significantly
Solution Approach 1:
The patent segments the complex multi-layer system into two separate, simpler coating systems on different glass sheets. This reduces the number of layers each individual coating must have, making manufacturing more economical while maintaining overall performance.
Solution Approach 2:
The patent uses pyrolytic layer systems on one or both glass sheets, which are cheaper to manufacture than cathode sputtering systems. While pyrolytic layers have lower individual emissivity performance, the combination of multiple sheets with these cheaper layers achieves comparable overall performance at reduced cost.
3Ease of manufacture
If pyrolytic layers are used instead of cathode sputtering, then manufacturing cost is reduced, but emissivity performance deteriorates
Solution Approach 1:
The patent combines pyrolytic layer systems on one or both glass sheets with the insulating gas fill to achieve the desired thermal performance. By merging the functions of the pyrolytic coatings with the gas fill, the system compensates for the lower emissivity of individual pyrolytic layers.
Solution Approach 2:
The patent creates a composite insulating glazing system that combines multiple materials and mechanisms: pyrolytic layer systems on glass sheets, insulating gas fill, and potentially low-emissive coatings on the inner surface. This composite approach allows the system to achieve high overall performance using cost-effective pyrolytic materials.
4Loss of energy
If low-emissive coatings are applied to reduce thermal transmission, then energy efficiency is improved, but visible light transmission and reflection neutrality are compromised
Solution Approach 1:
The patent applies low-emissive coatings selectively on the inner surfaces of the glass sheets, where they face the insulated space. This localized application ensures that the coatings primarily affect thermal radiation in the infrared spectrum while having minimal impact on visible light transmission and reflection properties that users observe.
Solution Approach 2:
The patent uses pyrolytic layer systems with specific optical and thermal parameters that allow them to be selective in their function. These layers are designed to have high emissivity in the infrared range (for thermal control) while maintaining high transparency in the visible range (for light transmission), thus changing the material's properties to serve multiple functions.
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
This approach results in glazing with improved emissivity and solar factor performance, achieving thermal transmission coefficients as low as 0.85 W/m²K and solar factors below 35%, while maintaining neutral reflection and high light transmission, effectively reducing energy consumption and meeting stringent architectural glazing requirements.
Implementation Method 1
thin transparent layers acting as selective filters for the transmitted wavelengths
Implementation Method 2
low-emissive properties
Implementation Method 3
high proportion of krypton in the insulating gas
Implementation Method 4
polishing the pyrolytic layers to reduce surface roughness
Data Source
Figure 1~3
AI summary
The invention relates to insulating double glazing comprising a sheet of glass having, on the face (2) thereof, a set of so-called low-emissive layers, produced by sputtering and comprising at least one infrared-reflecting metal layer, the other sheet of glass comprising, on the face (4) thereof, one or more layers of metal oxides deposited by gas pyrolysis, the space located between the sheets being sealed and filled with insulating gas consisting of at least 86% krypton by volume and at most 5% air, said glazing having a solar factor at most equal to 35% (for sheets of clear glass with a thickness of 4 mm).