When sustainability becomes a given

Stephan Ully, a specialist in technical chemistry, was responsible for the development of the Twilight Comfort fabric collection, which is completely free from PFAS and PVC.


Stephan Ully has been head of F&E ST at Sattler SUN-TEX since 2019. The R&D technician has a degree in technical chemistry as well as 20 years of professional experience in industrial companies, including 10 years in a managerial position.

What makes the Twilight Comfort collection so special, and what requirements does it fulfil?

Twilight Comfort was developed for areas of use that don’t require any flame retardant properties. When developing the textile, its appearance under transmitted light was a priority for us, and we created it using a specific blend of yarns. The colours were selected in such a way so as to provide excellent glare protection as well as permitting good transparency to the outside world. All of the fabrics were tested, as is customary for us, in an independent laboratory in accordance with EN 14501. This way we could give our partners technical data about the light to help with their planning.

When it comes to sustainability, Twilight Comfort is of course finished with a coating that meets all the privacy and glare protection requirements, without the use of PFAS.

«There is a very clear trend towards sustainability. But expectations for perfect technical properties have also risen.»

How have the requirements for the properties of the individual fabrics changed in recent years? 

There is a very clear trend towards sustainability. But expectations for perfect technical properties have also risen. Against the backdrop of increasing costs and compliance with legal regulations, this is a very challenging combination of requirements for us as developers.

What trends in textile properties can we expect in coming years?

The topic of sustainability will certainly be with us for some time before it becomes a given. In this respect, I also expect and hope that the jungle of labels and certificates will become somewhat clearer and that the market will only offer products with selected, reliable certifications that have been tested by independent institutes – and togher regulations will crack down on greenwashing.

What challenges did you face when developing PVC-free fabrics, and how did you solve them? 

We have been known for offering PVC-free privacy and glare protection products for a long time. This is why we can draw on a wealth of experience when developing new products of this kind. Particular challenges in this area include choosing the right yarns, the technical weaving density and the weave itself. It is only by optimally matching these parameters that it is possible to achieve a visually and technically outstanding product like our Twilight Comfort collection. For years we have focused on eliminating finishes containing PFAS, and Twilight Comfort is our first product range finished with completely PFAS-free coatings. So, not only PVC-free, but also PFAS-free.

For which products and building types is the Twilight Comfort collection particularly suitable?

Twilight Comfort is ideal for privacy and glare protection in vertical fabric blinds for zip-guided systems. The large width of the material (300 cm) provides a shading solution without seams. But if the installation does require a seam (areas > 300 cm), then it is extremely simple to create one – a real all-rounder and a win for textile shading in vertical fabric blinds. But Twilight Comfort is not just used for large window systems. Vertical fabric blinds are being installed more and more on balconies, as the sides to pergolas and niches to neighbours. The open weave of the fabric permits a pleasant exchange of air. You can also shut out unwanted views from the outside without shutting yourself off from the outside world.

The colour palette is simple – how did you decide on the colour selection? 

The colour palette was deliberately kept simple so it would combine well with the colours of common awning fabrics. It also intentionally tended towards the darker shades, as these ensure good transparency to the outside whilst also offering best heat protection. Because the fabric only lets in minimal IR light, the interior remains private and also shielded from the heat.

Discover the collection Twilight Comfort

Collaboration with Sattler SUN-TEX

We have been working with Sattler on the fabrics we use in our sun blinds and vertical fabric blinds for many years now. This Austrian company specialises in textile architecture and technical textiles for sun protection.

What is PFAS?

PFAS (per- and polyfluoroalkyl substances) are a group of synthetic chemicals used in a variety of products, such as textiles, packaging, and non-stick coatings as they resist water and grease. While these properties may seem useful, there are concerns about the impact PFAS have on our health and the environment.

PFAS-free products, i.e. made without these chemicals, offer several benefits:

  • Protection for our health: PFAS-free products help reduce the risk of potentially harmful exposure and protect people’s health.
  • Protection for the environment: By not using PFAS, you help reduce harmful impacts on the environment and the pollution of soils, water bodies, and living organisms.
  • Sustainability: The use of PFAS-free products supports more sustainable manufacturing and consumption practices that are consistent with protecting our environment.


By choosing PFAS-free products, you are helping to protect the health of people and nature, and promote a more environmentally conscious future

©Sattler Sun-Tex