Borosilicate glass - The all-rounder

Sustainability x Design I: We develop products that impress with their sustainability, design, and quality. To achieve this, we rely on selected materials, which we will present and explain in more detail in a series of blog posts.

In the first part of our series, we introduce the heart of the BELAMY bottle: our bottle made of borosilicate glass. If you paid attention in chemistry class, the term will sound familiar. You can read here what distinguishes this material from conventional glass and why we chose borosilicate.

In short

The name borosilicate glass derives from the high boron trioxide content. This makes this special glass highly temperature-resistant and enables a manufacturing process in which the product is exposed to extremely high temperatures and then suddenly cooled. This rapid temperature change compacts the material, giving it its exceptional lightness and stability. This high quality ensures exceptional durability. Furthermore, borosilicate glass is free of chemicals and BPA, making it ideal for storing beverages.

Glass is glass? Far from it!

Glass drinking bottles are becoming increasingly popular, as they offer an excellent alternative to plastic bottles, which are usually no longer usable after one use. The downside of many glass bottles, however, is their comparatively higher weight and fragility. To counteract this, BELAMY uses borosilicate glass. Because not all glass is created equal!

Commercially available bottles and other objects are typically made of soda-lime glass. Also known as regular glass, this material is the most common type of glass. Due to its chemical composition, it is correspondingly heavy. It is suitable for products that only need to withstand short-term chemical exposure and are not subject to high thermal stress. And it breaks easily.

It's a different story with glass bottles made of borosilicate glass. These can withstand even heavy impacts without breaking. Borosilicate glass is a highly chemical- and temperature-resistant glass. That's why most people remember it from chemistry class in the form of test tubes or Erlenmeyer flasks. But it's also found in households: baking dishes, casserole dishes, and other "fireproof" tableware are made from it. We, too, have discovered this wonder glass for ourselves and now use it to produce high-quality and sustainable glass and drinking bottles.

What makes borosilicate glass so special?

Borosilicate glass is also largely composed of sand. Another important component is boron. This element is also used in traditional glassmaking, but in much smaller quantities. Between 7 and 13 percent is boron trioxide, 4 to 8 percent is sodium oxide and potassium oxide, and 2 to 7 percent is aluminum oxide. This composition results in a very low coefficient of thermal expansion. Borosilicate glass is temperature-resistant up to at least 515°C – a temperature range you'll hardly ever reach in your kiln.

Borosilicate glass achieves its extremely high stability thanks to a special manufacturing process. During the manufacturing process, the borosilicate glass is exposed to extremely high temperatures and then suddenly cooled. This rapid temperature change causes the material to condense, giving it its exceptional lightness and stability.

Why borosilicate bottles?

We also take advantage of these properties. Our borosilicate glass drinking bottles offer numerous advantages over conventional glass.

1. Lighter yet stable

Conventional glass bottles are often made of extra-thick glass to make them as shatter-resistant as possible. However, this also makes them unnecessarily heavy. This isn't necessary with borosilicate glass, which, despite its light weight, is extremely stable and robust. It's therefore ideal for drinking bottles used on the go or during sports.

2. Temperature resistant - in heat and cold

Conventional glass shatters under the influence of heat. Soda-lime glass bottles should be filled with hot water, so be careful. This is not the case with borosilicate glass, which has a very low coefficient of thermal expansion. This allows it to withstand high temperatures while remaining clear and robust. Our bottles can therefore be safely cleaned in the dishwasher or filled with boiling water.

3. Abrasion and scratch resistant

Sooner or later, it happens: Your beloved glass bottle gets scratched and becomes cloudy. This can sometimes spoil your appetite for the drink inside. That's why the content of silicon dioxide and boron trioxide is significantly higher than in conventional glass. This ensures greater stability, scratch resistance, and increased transparency of the borosilicate glass. Our borosilicate glass drinking bottles won't scratch in your backpack or bag. They stay clear and beautiful and look like new for much longer.

4. Tasteless and free of harmful substances

Plastic is an absolute no-go for us when it comes to our drinking bottles. These materials not only contain many toxic substances and plasticizers, but they also leach into liquids and food, altering the taste of the contents. Drinks stored in plastic bottles for extended periods often have a strange, stale aftertaste.

Our borosilicate glass, on the other hand, is completely free of chemicals and BPA. It is essentially odorless and tasteless and has no cracks or grooves where troublesome bacteria can settle. The bottles do not absorb odors, flavors, or discoloration. The taste of the beverages remains unchanged, guaranteeing completely safe drinking pleasure.

5. Sustainable against plastic and environmental pollution

Crystal-clear water in every ocean, river, and lake: That's what we want, and to achieve it, we must rid our waterways of plastic waste. The road to achieving this seems long—but with the right attitude, we can achieve it together. An environmentally friendly drinking bottle made of borosilicate glass is a good step in this direction. The properties listed above ensure this: Its durability makes it a long-term companion and a statement against the throwaway society.

Many people still find plastic bottles practical. They are lightweight after use, or can simply be thrown away so they no longer need to be carried. Using reusable glass bottles, on the other hand, saves the environment a lot of plastic waste and prevents soil and water pollution. This applies to all types of glass bottles, of course. However, borosilicate is much more robust than conventional glass and therefore more durable. It even survives falls without being damaged. Instead of replacing them regularly, our borosilicate glass drinking bottle lasts a long time. This saves money, resources, and energy required to produce new bottles. Furthermore, borosilicate glass is 100% recyclable and can be reused infinitely without any loss of quality.

This is what makes our bottle so high quality

For these reasons, we at BELAMY deliberately opted for sturdy, heat-resistant borosilicate glass instead of conventional glass. The transparent glass showcases the diverse colors and designs particularly well. And with the dishwasher, regular cleaning is child's play. Our custom-made bamboo lid ensures a secure closure of the bottle, which is also resistant to carbon dioxide. See for yourself how the pleasant weight of 320g makes it ideal for on the go, something a conventional glass bottle can't match. Our borosilicate glass combines sustainability with practicality and, what is always our top priority, beauty!