SiOPack® Improves Process Stability and Water Barrier Performance of Dry-Fibre Packaging

New barrier technology stabilises dry-fibre geometries under humid processing conditions and improves downstream processing in industrial filling lines.

By Dieter Schwindt, certified expert for nanotechnology and surface applications

Dry-fibre packaging is regarded as a promising approach for reducing plastic-based packaging solutions. In industrial practice, however, one key problem becomes apparent: under humid processing conditions, the materials quickly lose mechanical stability. This can lead to deformation, disruptions in machine guidance and, in the worst-case scenario, downtime in filling lines.

This is particularly critical in applications involving high humidity or direct contact with liquids, as commonly found in the food and beverage industry. Existing hydrophobisation solutions often reach their limits here, as they either impair the forming process or are not optimally scalable from an economic and process-related perspective.

Challenges of Dry Fibre in Humid Processing Environments

Dry-fibre packaging reacts sensitively to increased humidity and direct contact with water. Even under moderate climatic conditions, a significant reduction in mechanical stability may occur.

In industrial filling lines – particularly in areas exposed to moisture or direct contact with liquids – this problem becomes even more pronounced. Components may swell or lose their shape, impairing machine guidance. The consequences include disruptions in the filling line, increased reject rates and potential downtime.

In practice, such effects often result in additional cleaning cycles and the need to restart the production line – a clear economic disadvantage.

Limitations of Existing Solutions

Conventional hydrophobisation methods such as AKD can only be used to a limited extent with dry fibre. A key principle in dry-fibre processing is to leave the fibres unaffected during forming, allowing processes such as stretching and drawing to proceed fully and without restriction.

The functional barrier is therefore deliberately applied only after the forming process. In many cases, this means that an additional external coating is required.

Alternative approaches – such as the use of MFC for hydrophobisation – are known, but are often associated with increased costs and reduced process speeds. An industrially scalable solution combining stable barrier performance with good processability therefore remains a challenge.

SiOPack® as a Solution Approach

With SiOPack® technology, a coating system is available that enables a stable water barrier on fibre-based materials without affecting the forming process. The aim is to reduce moisture absorption while simultaneously improving the mechanical stability of the components during downstream processing.

Results to date show that the use of suitable barriers can achieve significant improvements:

  • reduced moisture absorption
  • improved dimensional stability of dry-fibre components
  • more stable machine guidance during downstream processing
  • lower reject rates
  • increased process reliability in filling lines

Test Results Under Practical Conditions

The results achieved during investigations demonstrate improved storage and process stability. For example, storage periods of more than 150 days under non-climatised conditions were achieved without significant losses in top-load stability.

The results indicate potential for future applications in the field of hot beverages as well as other moisture-sensitive packaging applications.

Assessment by Industry Experts

Packaging expert Stephan Halstrick from HALSTRICK Consulting Services – The Packaging Experts examined the SiOPack® barriers in his own tests and sees particular potential for improving the process stability of dry-fibre packaging:

“Particularly in dry fibre applications, moisture can lead to a rapid loss of mechanical stability. The results show that suitable barriers – such as those achieved with SiOPack® – can help provide greater stability for different dry-fibre geometries and improve downstream processing in humid filling environments.”

Presentation at interpack 2026

The presented results will be shown and discussed with a specialist audience for the first time at the interpack 2026 in Düsseldorf. The focus will be particularly on the stabilisation of dry-fibre geometries under humid processing conditions.