Borax-free corrugated board

Until this year, Boron compounds were considered essential for the adhesive properties of glues used in corrugated board production. STI Group is one of the first companies in the industry to develop a glue formula that does away with Borax and similar additives.

Starch, water, caustic soda: these are the only ingredients used to make glue at the main STI Group production plant in Lauterbach since the beginning of this year. After exhaustive testing the production team eliminated Borax, which has been declared a cause for concern by REACH, the EU chemicals regulation.

STI Group is acting in the best interests of its customers and the wider community by developing a corrugated board adhesive with no adverse impact on health or the environment. Although STI Group has never been close to the reporting threshold of 0.1 percent for Borax in its packaging and display production, it wants to completely ban the substance at all its locations.

Simply replacing Borax with another chemical was not an option. Instead, process innovation leader Hartmut Greb and his team of experts at STI Group Lauterbach examined new additive-free formulas. The result has been positive for both the company and its customers.

Less ingredients, better production

A positive spin-off is that the revised glue formula has improved processing and handling properties. Because of the change in its viscosity, the new glue is easier to apply than the old glue. ‘So far, we have not had to compromise on process speed when using the new glue,’ says Greb.

All STI Group plants are planning to switch over to borax-free glue by the end of this year. ‘Our biggest challenge will be the high-performance machines, because they are especially sensitive to changes in production parameters,’ explains Greb. ‘But we are confident of finding a solution for these as well.’