Every day, we expect our phones to handle high-definition video calls, autonomous cars to operate smoothly, and fiber internet connection to stay fast, reliable, and capable of managing massive data traffic.
Meeting these high expectations requires advanced engineering materials—such as low-dielectric glass, used in copper clad laminates (CCLs) and advanced printed circuit boards (PCBs).
As fundamental building blocks of modern electronics, CCLs and advanced PCBs depend on low-dielectric glass to deliver performance, signal integrity, and long-term reliability for today’s most demanding technology.
In this glass you’ll find boron—a key elemental component that helps manufacturers engineer low-dielectric glass with the right consistency and precision.
What is low-dielectric glass?
Low-dielectric glass is a type of insulating glass that’s designed to not conduct electricity, making it ideal for maintaining signal integrity in high-frequency electronic applications.
In CCLs and PCBs, low dielectric glass improves electrical performance by reducing the dielectric constant and signal loss. It also contributes important mechanical properties such as:
- Dimensional stability
- High tensile strength
- Excellent adhesion with resin systems (essential for multilayer PCB reliability)
Chemically, its low alkali content enhances moisture and corrosion resistance—supporting long-term durability in challenging applications such as automotive, aerospace, and high-frequency communication systems.
Specialized alternative to standard E-glass
Low-dielectric glass shares many attributes as standard E-glass, which is commonly used in CCLs and conventional PCBs. Unlike “commoditized” E-glass, low-dielectric glass is specifically engineered with a lower dielectric constant (Dk) and dissipation factor (Df).
As modern technologies drive exponential growth in data traffic and processing power, so too does demand for high-frequency signals in electronic systems.
However, higher signal frequencies increase the risk of signal attenuation and loss. Advanced materials such as low-dielectric constant (low-Dk) glass play a critical role in addressing this challenge. By reducing dielectric loss, low-Dk glass helps maintain signal integrity, enabling reliable performance of CCLs and advanced PCBs in today’s high-speed, data-intensive applications.
Beyond reducing signal loss, a lower Dk also allows for more compact circuit designs, supporting the miniaturization of electronic components—a key requirement in modern high-frequency systems.
Together, these advantages make low Dk glass essential for advanced electronic applications that demand high-speed and large-traffic data processing.
Where to find low-dielectric glass
It’s likely that you haven’t noticed dielectric glass, but it’s everywhere.
5G communication equipment
5G networks operate at much higher frequencies than previous generations, delivering faster data speeds, ultra-low latency, and increased capacity to connect multiple devices simultaneously.
As a result, we can stream 4K videos in real-time, perform remote medical operations, and connect millions of smart devices across cities.
AI and data center servers
Modern AI systems, from voice assistants to computer vision platforms, require massive datasets to move rapidly between processing units.
To function efficiently, they depend on high-speed internal connections that minimize delays and enable fast, real-time decision-making. High-frequency signals are essential to support the speed, scale, and complexity of AI applications.
Advanced automotive systems
Modern vehicles use complex electronics for driver assistance, connectivity, and autonomous functions. Low-dielectric materials help these systems transmit data quickly and reliably to help drivers stay safe on the road.
Learn more about borates in EVs
Boric oxide’s role in producing low-dielectric glass
As in conventional E-glass, dielectric glass needs low alkali content to ensure electrical stability and minimize ionic conductivity. Non-sodium borates, such as boric acid (Optibor®) and boric oxide, are typically used for this application.
Low-dielectric glass typically contains a higher B2O3 content (15-25 wt%) than E-glass. The elevated B2O3 concentration is a key compositional driver of the superior dielectric properties in low-Dk glass fiber.
To achieve this high B2O3 loading, manufacturers prefer boric oxide rather than boric acid for the melting process. Boric oxide provides better control over glass formulation and melting behavior. Using boric oxide:
- Improves melting stability: Boric oxide is water-soluble at a much slower rate than boric acid. At higher B2O3 levels, boric acid introduces significant molecular water, which increases energy consumption, boron volitivity loss, and instability during melting.
- Enhances fiber quality: Excess molecular water can overwhelm the fining process, leading to trapped fine bubbles in the fiber. These bubbles may compromise both mechanical strength and dielectric performance.
- Increases fiber yield rate: Boric oxide address challenges around uniform melt viscosity, minimizing variation during fiber drawing and improving yield rate and fiber quality consistency.
Get more details on boron in glassmaking
Driving progress through a holistic approach
At U.S. Borax, we manage the full value chain—from mining borates to refinement to producing quality boric oxide. We ensure stable feedstock, consistent quality, and trusted supply for the refractory industry.
Our boric oxide is manufactured and packaged in Boron, California, a desert region with consistently low humidity. This stable environment helps minimize the risk of caking. And our technical expertise ensures consistent product quality for customers worldwide.
For decades, the glass industry has trusted U.S. Borax as a reliable and innovative partner. We remain committed to advancing boron chemistry and supporting our customers’ needs, including advanced applications such as dielectric glass. Contact our technical team for more information.
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