The issue of fire protection for buildings is prevalent primarily in public buildings. The building products used must be flame-resistant or non-combustible, depending on their place of use.

The topic of this presentation concerns innovative coatings for the fire protection of structural elements used in modern modular construction in order to increase their fire safety.

The developed products for painting modular building elements allow for the passive fire protection of structural elements thanks to their ability to delay the ignition of materials covered with them by reducing the spread of flames.

One of the directions we have taken in obtaining fire-retardant paint products was to replace toxic halogen systems with systems based on phosphorus compounds, which allow for their safe use in public buildings.

The focus of this study was on transparent products with short curing times. Both 1K and 2K water-borne and solvent-borne products were selected for testing.

A 2K PUR varnish based on a modified acrylic resin, a 2K epoxy varnish based on a modified epoxy resin, and a water-based varnish based on an acrylic dispersion resin were developed. A 20% addition of active flame-retardant fillers (polyphosphate and polyols derivatives) was introduced to each product.

The obtained varnishes exhibited excellent resistance to open flame exposure. The tests were conducted using a test stand to examine the ignitability of products under the influence of a small flame, in accordance with EN ISO 11925-2:2020.

In conclusion, during the research process, transparent flame-retardant varnishes for wooden substrates, both water-borne and solvent-based, were successfully developed. Careful selection of active fillers as retardants allowed the creation of user-friendly, easy-to-apply, and environmentally friendly products with high fire resistance.

This work was financially supported by the Łukasiewicz Research Network Centre (Poland), Grant number: 1/Ł-IMPiB/CŁ/2021