Whether wall panels contain formaldehyde depends on the product type:
- Melamine-faced panels (wood-based substrate): formaldehyde mainly comes from the substrate, then the decorative surface paper. The substrate is mostly wood fiber or veneer bonded with glue under heat and pressure — the formaldehyde comes from the adhesive (many manufacturers now use MDI formaldehyde-free glue); the surface paper is melamine-impregnated, which also introduces a small amount (formaldehyde-free melamine adhesives are now available in the industry).
- WPC / PVC panels: generally formaldehyde-free — the substrate is mainly PVC resin and calcium powder, and the surface film is bonded with PUR adhesive, which also contains no formaldehyde.
China's national standard requires wood-based panel products to meet the E0 grade for formaldehyde emission. Products from established manufacturers all meet the standard.