Smart glass coating could cool glass buildings

 Researchers at the Fraunhofer Institute have developed a smart coating for building glass that can automatically darken in sunlight. This technology combines electrochromic and thermochromic materials, responding to both electrical stimuli and temperature changes. In modern buildings with extensive glass curtain walls, the coating effectively reduces indoor overheating caused by solar radiation, thereby decreasing reliance on energy-intensive air conditioning systems.

The construction industry is one of the major sources of global greenhouse gas emissions. In Germany, for example, according to statistics from the Federal Environment Agency, the building sector accounts for approximately 30% of the country's carbon dioxide emissions and 35% of its energy consumption. Buildings with large glass facades and roofs, especially office structures, experience sharp rises in indoor temperatures during strong summer solar radiation. Traditional shading devices such as blinds and curtains often compromise visual aesthetics and obstruct views. As a result, such buildings commonly rely on air conditioning for cooling, leading to high electricity consumption and an increased carbon footprint.

To address this issue, the Fraunhofer Institute for Silicate Research (ISC) and the Fraunhofer Institute for Organic Electronics, Electron Beam, and Plasma Technology (FEP) jointly led the EU-funded "Switch2Save" project. They collaborated with universities and industry partners across several European countries to advance the development and application of smart window coating technology.

In this smart coating system, the electrochromic component is based on a transparent conductive film. Applying voltage to the film triggers the migration of ions and electrons, enabling the glass to reversibly transition from transparent to dark. The thermochromic coating, on the other hand, automatically reflects solar heat when the ambient temperature reaches a specific threshold, operating without external power as a passive response mechanism.

The electrochromic elements can be integrated with sensors and a control system to monitor light intensity and temperature in real time. When values exceed set parameters, the system sends an electrical signal to the conductive film, gradually darkening the glass. This effectively blocks heat input and provides anti-glare functionality. On cloudy days or at night, the glass returns to full transparency, maximizing the introduction of natural light.

The technology has already been implemented in practical building applications. For instance, this smart glass system has been installed in the pediatric clinic of a large hospital in Athens, Greece, and an office building in Uppsala, Sweden. Researchers will conduct a year-long energy consumption monitoring study to compare electricity usage of air conditioning systems before and after retrofitting, verifying energy-saving performance under real climatic conditions.

In terms of manufacturing, the team employs wet chemical processes and vacuum coating technology. The electrochromic coating is integrated onto a flexible polymer film, while the thermochromic layer is prepared on an ultra-thin glass substrate. Roll-to-roll production methods enable economical and scalable manufacturing. The final product is only a few hundred micrometers thick and weighs less than 500 grams per square meter, making it easy to install in existing building windows without structural modifications.

Currently, the project team is focused on further enhancing the technology’s applicability. Efforts include combining electrochromic and thermochromic units to improve regulatory flexibility, developing coating processes suitable for curved glass, and expanding color options beyond gray and blue to meet diverse architectural aesthetic needs.

As global warming and the EU Green Deal advance, the demand for energy-efficient building technologies is growing rapidly. All buildings in the EU are expected to achieve carbon neutrality by 2050. Smart window technologies like Switch2Save are poised to play a key role in promoting the low-carbon transformation of the construction industry.

U-Shaped Glass: Technical Specifications and Applications

 

1. Definition & Production Process

U-shaped glass, also known as channel glass, is a building glass material manufactured from recycled glass and quartz sand. Key production stages include:

• Melting at 1470°C

• Forming via continuous rolling process

• Annealing treatment
  Optional enhancements:

• Embedded wire mesh for reinforcement

• Textured surfaces using patterned rollers

2. Classification Systems

Category	Types/Parameters
Surface Finish	Standard fine pattern, Wave pattern, Fine stripe, Thick stipple, Transparent
Mechanical Strength	Standard (≥70MPa flexural strength), Tempered (≥150MPa), Film-reinforced
Color Treatment	Clear, Color-glazed, Filmed, Sandblasted/Frosted

3. Key Technical Properties

Property	Performance Data
Optical	85% light transmission (single layer); <50% transmission (double U-section with air gap); Reduces light pollution via diffuse reflection
Thermal	U-value down to 1.84 W/(m²·K); 30% improved insulation when filled with thermal materials
Mechanical	Withstands structural deformation stresses; Vertical span up to 6 meters

4. Architectural Applications

• Facades:

  • Double-skin curtain wall at Shenzhen Bay Super Headquarters Base

  • Curved facade at Shanghai Expo Chile Pavilion

• Interiors:

  • Light-transmitting partitions at Wanho Haomei Art Hotel

  • Landscape screens at Ningbo Jiuzhuli Project

• Special Structures:

  • Airport terminal skylights (designed to DIN-1249)

  • Illuminated art walls at Shanghai Glass Museum

5. Installation Requirements

• Joint Design:

  • Elastic gaskets + flexible sealants

  • ±15mm joint width for thermal expansion

• Geometric Limits:

  • Max. height: 6m

  • Min. curvature radius: 500mm

  • Vertical tolerance: ≤5mm (≤5m height), ≤7mm (5-7m height)

• Structural Compliance:

  • Transfers loads to main structure via aluminum frames

  • Non-load-bearing use only

  • 10-20mm air layer mandatory in double-layer installations

The Truth Behind the 0.1% Tempered Glass Self-explosion Rate: 5 Major Project Selection Pitfalls and a Scientific Guide

 In 2025, a 1,200 square meter curtain wall at Dubai Marina Tower required emergency replacement due to spontaneous glass explosions, resulting in a direct loss of $2.3 million. Globally, there are 37 construction accidents caused by spontaneous glass explosions each year. As a project manager, do you have a true risk control plan?

1. Overturning Perceptions: The Scientific Truth Behind the Self-Explosion Rate
1.1 Visualization Experiment on the Root Cause of Self-Explosion
▷ Ordinary Soda-Lime Glass: Nickel Sulfide (NiS) Content ≥ 0.04g/㎡ → Differences in Thermal Expansion Coefficients Cause Localized Stress Concentration
▷ Ultra-Clear Glass Raw Materials: Iron Content ≤ 0.015% → 83% Reduced NiS Formation Rate (Source: Glass Journal 2025)

1.2 Comparison of Authoritative Data
Glass Type Average Self-Explosion Rate After Homogenization Treatment (HST) Hot-Dip Process Cost
Ordinary Tempered Glass 0.3%-0.4% 0.08% +$1.2/㎡
Ultra-Clear Tempered Glass 0.07% <0.01% +$0.8/㎡
💎 Key Conclusion: Ultra-clear glass combined with a two-stage HST treatment can reduce lifetime maintenance costs by 52% (calculated based on a 20-year construction cycle).
II. Five Deadly Traps in Project Procurement
Trap 1: Superstitious Devotion to "International Brands" and Ignoring Raw Material Traps
▷ Tragic Case: A landmark Southeast Asian project sourced European-branded glass. Excessive iron content in the raw materials resulted in a 0.5% spontaneous explosion rate.
▷ Scientific Circumvention: Require suppliers to provide a source report for the raw glass sand (e.g., we use Cristal Mining ultra-clear sand from Australia).

Trap 2: Failing to Clearly Define Cutting Accuracy Tolerances
[Comparison Chart: Curtain Wall Installation Results of ±0.3mm CNC Waterjet Cutting vs. ±1.2mm Conventional Cutting]
▷ Cost: A tolerance >±0.8mm results in an average installation delay of 2.3 weeks.
▷ Our Solution:
→ Italian BAVELONI CNC Cutting Line with ±0.3mm Error
→ Free CAD Drawing Optimization Services

Trap 3: Lack of Field Wind Pressure Measurement Data
▷ Mandatory Inspection Items for Hurricane Zones:
- Basic Requirement: ≥4000Pa (National Standard GB/T 15227)
- Requirement for High Wind Zones: ≥9000Pa (e.g., coastal/super-high-rise buildings)

Trap 4: Ignoring Edge Stress Concentration
[Insert Micrograph: Edge Roughness Comparison]
▷ Poor Edge Grinding → Stress Concentration Factor Increases by 300%
▷ Our Process:
→ German Bystronic Fine Grinding Line + Argon Ion Polishing
→ Edge Stress ≤12MPa (EN 12150 upper limit is 24MPa)

Trap 5: No Self-Destruction Warranty During Acceptance
▷ Unwritten Industry Rule: Most Suppliers' Warranties Only Cover "Manufacturing Defects" and Exclude the Risk of Self-Destruction
▷ Our Commitment:
→ Written Commitment: 0.1% Self-Destruction Rate Guarantee
→ 72-Hour Response for Self-Destruction Replacement
III. Joy Shing A Revolution in Glass Quality Control
China Construction Group Zhuhai Project Demonstrates
"Using our 12mm ultra-clear tempered glass:

Consumption: 86,000 m2
Lifecycle: 3 years
Self-explosion record: 0 (verified by regular thermal imaging testing)"

Float Glass: The Unsung Hero of Our Transparent World

 The windows, car windshields, phone screens, and even glass furniture you interact with daily mostly originate from one revolutionary process – float glass. It silently underpins our modern lives.

The Core Mystery: How Float Glass is Made

Before float glass, flat glass production was laborious and time-consuming. In 1959, UK's Pilkington Company successfully developed the float process, revolutionizing the industry.

Its secret lies in a bath of molten tin:

1. Melting Raw Materials: Sand, soda ash, and other materials melt into glass in a high-temperature furnace (around 1600°C).

2. Floating on Tin: The molten glass is poured onto the surface of the molten tin. Due to density differences, it naturally spreads out, forming an even thickness.

3. Perfect Formation: Under gravity and surface tension, the glass forms an incredibly smooth, mirror-like surface – no polishing needed! Thickness is controlled by temperature and drawing speed.

4. Annealing & Strengthening: The glass ribbon moves into a long annealing lehr for precisely controlled cooling. This removes internal stresses and significantly increases strength and stability.

5. Cutting to Size: The cooled, hardened glass ribbon is automatically cut into sheets of the required size.

The Outstanding Qualities of Float Glass

This unique process gives float glass unmatched advantages:

• Exceptional Flatness & Optical Quality: The tin-formed surface is ultra-smooth with virtually zero optical distortion, providing clear vision.

• Flexible Thickness Control: Ranges from ultra-thin (0.5mm) to ultra-thick (25mm), meeting diverse needs.

• High Purity & Uniformity: Strict material and process control minimizes bubbles/stones, ensuring high, consistent light transmission.

• Superior Cost-Effectiveness: Continuous, large-scale, automated production lowers costs, making quality glass widely accessible.

• Excellent Processability: Easily undergoes deep processing like tempering, laminating, coating, or insulating to create safety glass, energy-efficient glass, decorative glass, and more.

Ubiquitous Transparency

Float glass is everywhere in modern life:

• Architecture: Curtain walls, windows, doors, skylights – providing views and light.

• Transportation: Car windshields/windows, train/aircraft windows – ensuring safety.

• Technology: The foundation for displays in phones, tablets, TVs, etc.

• Home & Industry: Glass furniture, mirrors, solar panel covers, instrument windows.

The Future: Transparency & Sustainability

The float process continues to evolve:

• Greener: Optimizing fuels (e.g., natural gas, hydrogen), improving furnace efficiency, reducing emissions.

• Smarter: Applying automation, big data, and AI to boost efficiency and quality.

• Stronger: Developing ultra-thin, ultra-thick, ultra-clear, high-strength specialty glass.

• Recycling: Increasing the use of recycled cullet (waste glass) to save resources and energy.

Thermal cracking mechanism and engineering response of single-piece fireproof glass

Introduction

As a key material for building exterior protection, the thermal cracking behavior of glass in fire directly affects the escape of personnel and the spread of fire. This article focuses on the thermal cracking mechanism of **single-piece fireproof glass (DFB)** and analyzes its fire-resistant nature.

1. The core driving force of thermal cracking: temperature difference stress

Research has confirmed (Xie, Keski-Rahkonen, etc.) that the fundamental cause of glass cracking is the critical thermal stress caused by **uneven heating:

Ordinary soda-lime glass: critical temperature difference is only **80~90℃

6mm tempered fireproof glass**: critical temperature difference **330~380℃

10mm tempered fireproof glass**: critical temperature difference **470~590℃

When the temperature difference between the exposed area (fired) and the shielded area (frame) of the glass exceeds the threshold in a fire, the tensile stress generated exceeds the tensile strength of the glass (usually 30~50MPa), which triggers the crack.

2. Key factors affecting cracking

| Edge processing quality | Mechanical polishing edge strength (78MPa) > rough grinding edge (56MPa), micro crack expansion strength attenuation 15%+ |

| Installation method | Point support stress concentration > frame installation; aluminum frame fire resistance > wooden frame |

| External intervention | Spray cooling will accelerate cracking when the glass temperature is > 250℃ |

| Glass type | Borosilicate glass (expansion coefficient 4×10⁻⁶/K) Thermal shock resistance Rolled soda-lime glass (9×10⁻⁶/K)

📌 Engineering warning: Fireproof glass design must reserve a safety factor K≥2.5 (refer to curtain wall specifications)

3. Technical breakthrough direction

1. Material upgrade

Borosilicate glass: low expansion + high softening point (800℃), the mainstream fire protection solution in Europe, and has broken through the bottleneck of mass production in China

Microcrystalline glass: zero expansion characteristics, temporarily limited to high-end special applications

2. Process control

Stress strengthening: surface compressive stress > 90MPa (national standard bottom line) can improve bending strength (formula: σ≈0.83σ tempering + 38)

Edge finishing: HF acid etching/mechanical polishing to reduce microcracks

3. Intelligent simulation application

Thermal-mechanical coupling simulation based on tools such as ANSYS can predict:

Stress distribution of different installation methods (see Figure 1)

Critical rupture time (error <10%)

Simulation confirms: The maximum tensile stress of framed glass is concentrated at the junction of the frame and shielding (31~32MPa)

IV. Engineering application suggestions

1. Carefully select glass type

Borosilicate monolithic fireproof glass (EN 12600/ANSI Z97.1 certification) is the first choice for high-end projects

Strictly control the discrete risk of soda-lime-silicon fireproof glass

2. Optimize installation design

Preferentially use a four-point support structure to reduce stress concentration

The shielding width needs to be verified by thermal simulation

3. Scenario protection

Avoid enabling the sprinkler system at high temperature (>250℃)

Conclusion

To understand the mechanism of thermal cracking, it is necessary to make breakthroughs in three dimensions: material nature (boron silicon > sodium calcium), process precision (edge ​​stress control), and installation science (thermal stress dispersion). With the large-scale mass production of domestic borosilicate glass and the popularization of digital simulation technology, the safety of fireproof glass will achieve a qualitative leap.

Custom toughened glass shower doors

For custom shower doors, safety-tempered glass is mandatory. It's stronger and shatters into small, blunt granules if broken, minimizing injury risk. Thickness selection is critical:

• 8mm: Most common, offers good stability.
• 6mm: Suitable for small doors or fixed panels.
• 10/12mm: Used for oversized or frameless doors, providing maximum solidity.

Optional features enhance function and aesthetics: laminated glass (extra safety), frosted/sandblasted glass (privacy), Low-E glass (heat retention).

Hole-drilling processes are vital:

1. Timing: All holes (for hinges, handles, etc.) MUST be drilled BEFORE tempering. Drilling after tempering causes instant shattering.
2. Precision: Holes require exact measurement and positioning based on design drawings, typically using specialized equipment (like CNC machines or waterjets) for accuracy.
3. Edge Treatment: Hole edges must be finely ground and polished to remove any chips or micro-cracks. This prevents stress concentration (which can cause spontaneous breakage) and ensures smooth, secure hardware installation.

In short: Choosing the correct, safe glass thickness and ensuring precise pre-tempering hole drilling and polishing are core to the safety and durability of custom shower doors.

Joy Shing Glass factory direct sales, wholesale purchase price is more favorable.

We can process glass as required, including size, shape, edge, corner, hole, groove, etc.

If you are looking for high-quality toughened glass, please contact us for quotation and sample.

Tempered Glass: The Safe & Strong Choice - Professional Manufacturing & Customization by Joy Shing Glass

     In modern architecture, home design, and industrial applications where aesthetics meet safety demands, ordinary glass often falls short. Tempered glass, renowned for its exceptional strength and unique safety properties, stands as the trusted solution. As experts in glass manufacturing, Joy Shing Glass breaks down the core advantages and types of tempered glass, delivering reliable, professional manufacturing services.

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1. Tempered Glass: More Than Just "Harder" Glass

Tempered glass (also known as toughened or safety glass) is created by subjecting high-quality float glass to a precisely controlled thermal process (heating to high temperatures followed by rapid, uniform cooling). This process builds powerful compressive stress layers within the glass, granting revolutionary properties:

Multiplied Strength:

Impact resistance 3-5 times higher than ordinary glass; bending strength 2-3 times higher.

Superior thermal shock resistance, withstanding temperature differentials up to 200-250°C, minimizing the risk of thermal breakage.

Safety First:

Core Advantage! Upon forceful impact, it shatters instantly into countless small, blunt, honeycomb-like granules, drastically reducing injury risks – making it true "safety glass".

Reliable & Durable:

High strength ensures better resistance to scratches, abrasion, and everyday impacts, extending its lifespan.

> Joy Shing Glass Key Note: Once tempered, glass cannot be cut, drilled, or reworked. All customization needs (size, shape, holes) must be finalized before the tempering process – a crucial step in our professional manufacturing flow.

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2. Tempered Glass Types for Diverse Needs (All Customizable by Joy Shing Glass)

We offer a diverse range of tempered glass products to meet your specific project requirements:

1、By Strength & Safety:

Fully Tempered Glass: The Standard Choice! High strength, excellent safety (granular breakage). Widely used in doors, windows, curtain walls, shower enclosures, furniture tops, appliance panels – anywhere requiring personal safety protection. (Joy Shing Glass Core Product).

Heat-Strengthened Glass: Moderate strength (~2x ordinary glass). Breaks into larger, sharper shards – not classified as safety glass. Suitable for applications needing high flatness, moderate strength, and no strict safety         requirements, like some interior partitions or curtain walls (designed to prevent total fallout). Always confirm safety needs!

2、By Shape:

Flat Tempered Glass: The most common type, available in various thicknesses.

Bent Tempered Glass: Specialized Craftsmanship! Glass is heated, bent to a specific curve, then tempered, combining strength with elegant form. Ideal for curved facades, architectural features, premium furniture, display cases. Joy Shing Glass utilizes advanced bending/tempering technology to accurately realize your design vision.

3、By Functional Combination (Often using Tempered Glass as Base):

Tempered Laminated Glass (PVB/SGP): Tempered glass + high-strength interlayer (e.g., PVB or SGP film). Even if shattered, fragments adhere to the interlayer, preventing penetration and fallout – top-tier safety! Essential for skylights, canopies, railings, banks, and high-risk curtain walls. Joy Shing Glass offers various interlayer options for different safety grades.

Tempered Insulated Glass Unit (IGU): Tempered glass + sealed dry air/gas cavity. Exceptional thermal insulation & soundproofing! The go-to for energy-efficient building windows and curtain walls. We provide Low-E coated tempered IGUs for enhanced energy savings.

Tempered Coated Glass (Solar Control / Low-E): Surface coating applied before tempering. Controls solar heat gain, reduces radiation, boosts energy efficiency. Key for high-performance building envelopes. Joy Shing Glass offers custom coating solutions.

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3. Joy Shing Glass: Your Professional Tempered Glass Manufacturing Partner

Choosing tempered glass means choosing safety and quality. Choosing Joy Shing Glass means you get:

✅ Professional Manufacturing: Utilizing advanced tempering furnaces and strict process control to ensure every piece meets strength standards and safety reliability.

✅ Flexible Customization: Whether standard flat, complex bent shapes, large formats, or special thicknesses – we produce based on your detailed drawings and specifications (all cutting, edging, hole drilling, notching done before tempering).

✅ Quality Certification: Products comply with relevant national safety standards (e.g., GB 15763.2), with critical products carrying CCC certification.

✅ Complete Solution Provider: We supply not only premium tempered glass but also laminated tempered, insulated tempered, coated tempered, and other composite products.

✅ Reliable Supply: Stable production capacity ensures your project timelines are met.

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4. Get Started: Infuse Safety & Strength into Your Project!

Tempered glass is ubiquitous: from the sturdy curtain walls of skyscrapers to the safe shower screens in your home, from elegant furniture tops to protective panels on devices. It's the indispensable safety cornerstone of modern design.

Planning a project? Need a reliable tempered glass solution?

> > Contact the Joy Shing Glass Team Today! <<

l We'll recommend the optimal tempered glass product or combination based on your specific application (architecture, home, furniture, appliances, specialty uses), safety level requirements, performance needs (strength, energy efficiency, soundproofing, aesthetics), and budget.

l Receive expert material selection advice and technical support.

l Benefit from fast responses to your quotes and customization requests.

Choose Joy Shing Glass for professionalism, safety, and guaranteed quality. Let's build stronger, safer spaces together!