German Company Wants to Revolutionize the Glass Market

Thin glass shatters, nobody likes to carry heavy glass bottles: glass as a material has advantages and disadvantages. Thanks to a new technology, even lightweight glass can be made shatterproof and scratch-resistant – and at prices that make sense for mass production, says Michael Heidan, co-founder and Managing Director of ReViSalt GmbH. The fact is that glass is made from sand, can be recycled, and is, therefore, an environmentally friendly packaging material. Nevertheless, glass needs to become more sustainable, says Heidan.

The company, which was founded in Freiberg in Saxony, offers glass packaging manufacturers the opportunity to make glass products lighter, thinner, more shatterproof, and more energy efficient. With what Heidan calls a “disruptive technology” for rapid solidification, the glass can be chemically made harder in just a few minutes.

Chemical Speed  Strengthening

The technology of chemical speed strengthening (SCV) enables the glass industry to produce more economically and open up new markets. “Our innovation makes it possible to utilize the advantages of strengthened glass in almost all glass products for the first time. The amount of material used is reduced and the service life is increased, which saves resources and protects the environment. The reduced use of materials also leads to faster production,” explains Heidan.

Previously, the chemical strengthening process took up to 24 hours. The glass is immersed in a liquid salt bath at a temperature of 400 to 450 degrees Celsius, resulting in an exchange of potassium and sodium ions, which makes the glass stronger. The new method developed by Heidan’s team shortens this process many times over: “It takes us 5 to 10 minutes instead of 24 hours. A higher strength is achieved after 30 minutes.”

These innovations not only mean higher product quality but have also contributed to the use of thinner and lighter glass. These optimizations now make the technology available for consumer goods at reasonable prices, which can save resources and energy on a large scale, says Heidan. A 0.7-liter returnable glass bottle can now weigh 230 grams instead of the previous 600 grams thanks to the new technology. “A whole new world is emerging that we can achieve with glass,” says Heidan. He sees its potential as comparable to the invention of the refrigerator or digital photography. ReViSalt has already met with great interest in the glass industry. Heidan did not mention any customer names during the FACHPACK presentation, but it is known that the Bavarian company Heinz-Glas is one of the first customers to solidify products with the new technology.

Regeneration Material for the Salt Bath

The company has developed another innovation to make glass more sustainable: Salt bath regeneration. It solves the problem of ageing molten salt. When a quality limit is reached, the salt has to be renewed. The liquid salt is cooled from over 400 °C, disposed of at great expense and new salt has to be remelted over a period of days. Material costs and downtimes result in high process costs. The alternative developed by the Freiberg team is salt bath regeneration – the ingredients for this are a trade secret, but the application is said to be very simple: the regeneration material is dipped into the salt bath like a tea bag, remains there for 24 hours and can then be completely removed.

Background: The start-up’s vision of realizing high-strength glass for mass products took shape in 2017 when Heidan and his colleagues spoke to experts about the “Superfest Glas” from the GDR era, which was produced at VEB Sachsenglas Schwepnitz. In collaboration with the TU Bergakademie Freiberg, an initial research project was realized, the SCV technology was validated, and 2MH Glas GmbH was founded in 2019. In 2024, 2MH Glas GmbH merged with ReViSalt GmbH.

By Anna Ntemiris, editor