Fibre-based materials for converters
High-performance fibre-based packaging materials for flexible converting
Low to high barrier fibre solutions designed for recyclability, performance and efficient converting
PPWR-ready fibre-based packaging materials for converters
Walki supplies unprinted fibre-based packaging materials for converters, printers and packaging manufacturers looking to transition from plastic laminates to recyclable fibre-based structures.
Our materials combine strong fibre content, reliable sealing and tailored barrier performance, enabling converters to deliver packaging that meets performance expectations and future packaging regulations.
Walki fibre-based materials are available with low, medium and high barrier properties, supporting a wide range of food and non-food packaging formats.
Designed for efficient converting and high-speed production, Walki materials provide consistent machinability and excellent print surfaces across flexo, rotogravure and offset processes.
Solutions include:
- Natural polymer coated fibre materials
- Dispersion-coated barrier materials
- Optimised PE-coated structures
- Fibre-based lidding materials
All solutions are developed to support PPWR-ready packaging portfolios and paper-stream recycling.


Our fibre-based
portfolio
A complete range of recyclable fibre materials designed to replace plastic laminates across flexible packaging and lidding applications.
Walki Natural Polymer
Plastic-free fibre materials with natural polymer coating
Natural Polymer solutions use biodegradable coatings derived from food-industry side streams, replacing fossil-based plastics.
Designed for flow-pack and secondary packaging, these materials offer heat sealing and short-term barrier protection while remaining fully compatible with fibre recycling.
Key benefits
- Plastic-free heat sealing
- Microplastic-free design
- High fibre yield in recycling
- Runs on existing flow pack lines
Walki®
EVO Seal
Dispersion-coated recyclable fibre material
Walki®EVO Seal delivers medium to high barrier performance with a typical fibre content above 90%.
The dispersion coating provides reliable grease and moisture resistance while maintaining recyclability in paper streams.
Key benefits
- High fibre content
- Reliable heat sealing
- Medium–high barrier protection
- Designed for PPWR recyclability
Walki®
Opti Seal
Optimised PE-coated fibre material
Walki®Opti Seal combines strong fibre content with an efficient polymer layer designed for paper recycling.
The optimised PE coating provides dependable moisture and grease protection with minimal plastic use.
Key benefits
- Up to 95% fibre content
- Strong seal integrity
- Excellent machinability
- Efficient repulping
Walki®
Lid
Fibre-based lidding material with high barrier
Walki®Lid is a fibre-based lidding solution designed to replace aluminium and plastic lids.
It combines coated fibre with a peelable high-barrier layer, providing excellent protection against oxygen and moisture.
Key benefits
- Metal detector compatible
- High barrier protection
- Easy peelability
- Strong sealing
- Excellent print surface
| Solution | Barrier level | Heat seal | Fibre content | Recycling stream | Typical use |
|---|---|---|---|---|---|
| Walki®Natural polymer | Low | Yes | Above 95% | Standard paper | Secondary packaging |
| Walki®Opti Seal | Medium – High | Yes | Up to 95% | Standard paper | Food & non-food |
| Walki®EVO Seal | Medium – High | Yes | Up to 90% | Standard paper | Food & non-food |
| Walki®Lid | High | Yes | Above 70% | Standard paper | Cup lids |
Barrier solutions from low to high performance
Walki fibre-based materials cover a wide range of barrier requirements, from basic protection for secondary packaging to advanced barrier performance for sensitive products. This allows converters to select the most suitable structure based on product sensitivity, shelf-life expectations and packaging format.
Low barrier solutions

Low barrier materials are designed for applications where basic protection and sealing performance are sufficient. They provide good handling strength and very high fibre content with excellent recyclability. Walki Natural Polymer solutions are ideal for secondary packaging, bundling and dust-protection, offering plastic-free heat sealing and compatibility with fibre recycling systems.
Medium barrier solutions

Medium barrier materials provide balanced protection against moisture and grease while maintaining high fibre content and efficient recyclability. Walki®Opti Seal and Walki®EVO Seal offers reliable sealing, smooth machinability and stable barrier performance with minimal polymer use. These materials are suitable for many food and non-food flexible packaging applications requiring dependable protection.
High barrier solutions

High barrier materials provide enhanced protection against moisture, oxygen and external influences, supporting sensitive products and extended shelf life. Walki®Opti Seal, Walki®EVO Seal and Walki®Lid deliver strong barrier performance with reliable sealing and high fibre content. These solutions enable converters to replace plastic or aluminium structures while maintaining packaging performance and recyclability.
Fibre-based solutions designed for modern converting
Walki fibre-based materials combine:
- High fibre content structures
- Stable sealing windows
- Reliable barrier performance
- Smooth converting behaviour
- Excellent printability
Materials are tested on industrial and pilot equipment to ensure consistent performance on:
- VFFS lines
- HFFS lines
- Flow pack lines
- Lidding lines
Customisation
Walki offers extensive customisation options to match converting and packaging requirements. Customisation options include:
Barrier performance
- Moisture resistance
- Grease resistance
- Oxygen barrier
- Aroma protection
Material properties
- Grammage
- Thickness
- Fibre types
- Surface finish
Converting properties
- Seal strength
- Seal temperature
- Friction properties
- Stiffness
Barrier Formats
- Reel widths
- Sheet formats
- Tailored lengths

Who uses Walki fibre-based materials
Walki fibre-based materials are designed for flexible packaging converters, printing companies and packaging manufacturers producing fibre-based packaging solutions. They are also used by material distributors and traders supplying packaging substrates to brand owners. The materials support efficient converting and enable customers to deliver recyclable fibre-based packaging across food and non-food applications.

Flexible packaging converters
Producing flow packs, pouches and wraps.
Printing companies
Flexo, rotogravure and offset printing operations.
Packaging distributors and traders
Supplying materials to packaging users.
Packaging manufacturers
Producing primary and secondary packaging.
Brand owners (via converters)
Food and non-food packaging applications.
What makes Walki fibre-based materials different
Walki fibre-based materials combine high fibre content, tailored barrier performance and reliable converting behaviour in one integrated portfolio. Developed together with converters and brand owners, the materials are designed for efficient production, consistent sealing and excellent print quality, while supporting recyclability in paper streams and helping customers transition from plastic laminates to fibre-based packaging solutions.
Research & Development
Technology & Innovation Behind

Technical Competence Centres
Our fibre-based materials for converters are developed at Walki’s Technical Competence Centres in Finland, Germany and Poland, where in-house coating and extrusion expertise drives continuous innovation. By refining technologies rooted in papermaking and barrier engineering, we create high-performance fibre structures designed for efficient converting. Recyclability is built into the design from the start, ensuring strong fibre recovery and future-ready packaging solutions.

Pioneering the future of fibre-based barrier production
At Walki, we’ve brought our next-generation production line to life. Designed entirely in-house and built to set new standards in sustainable barrier materials.
This state-of-the-art line integrates dispersion technologies, enabling us to produce high-barrier fibre-based materials with a low carbon footprint, without compromising recyclability. It’s a strategic expansion of our technology base, ensuring that our fibre-based solutions meet even the strictest future regulatory requirements.
The line responds to the fast-growing demand for recyclable, fibre-based alternatives. It marks a significant step forward in our ambition to deliver high-performance materials that support a circular economy.
Walki fibre-based materials are unprinted packaging substrates made primarily from fibre, designed for converters producing flexible packaging and lidding materials. They combine barrier performance with recyclability in paper streams.
Yes. Most Walki fibre-based materials are designed to be recyclable in standard paper recycling streams, with high fibre recovery rates depending on the structure.
Walki materials are designed to support PPWR recyclability requirements, including high fibre content and compatibility with paper recycling systems.
Yes. Walki materials are designed for existing converting and packaging equipment, including VFFS, HFFS and flow pack lines.
Walki fibre-based materials are available in low, medium and high barrier. This allows converters to match packaging performance to product needs.
How can we help you today?
Please share your queries by completing the form below. Our team of experts will get in touch with you as soon as possible to assist you.
