HEAT AND PRESSURE GENERATED DESIGN

1 . A method of manufacturing a building panel having a structured surface with a design that comprises colour variation in register with the structure whereby the method comprises the steps of:

applying a layer comprising a mix of fibres, binder, wear resistant particles, and a coloring substance on a carrier wherein the mix is floatable under heat and pressure; and

applying heat and pressure on the mix by a structured matrix comprising protrusions and cavities such that a controlled floating of the mix is obtained by the varying pressure distribution applied on the surface.

2 . The method according to claim 1 , wherein the binder content in the layer is adapted to the pressure such that a sufficient floating is obtained.

3 . The method according to claim 1 , wherein the binder is a resin.

4 . The method according to claim 1 , wherein the binder is a resin and the weight content of the resin is at least 40% of the layer.

5 . The method according to claim 1 , wherein the mass ratio between resins and fibres is in the range of about 130-240%.

6 . The method according to claim 1 , wherein the mass ratio between resins and fibres is about 190%.

7 . The method according to claim 1 , wherein the mass ratio between binder and the sum of the masses of the fibres and the coloring substances is higher than about 60%.

8 . The method according to claim 1 , wherein the applied temperature is higher than about 150° C. and the applied pressure is more than about 30 bar.

9 . The method according to claim 1 , wherein the layer comprises a top-layer and a sub-layer having different colour pigments which are mixed by the floating.

10 . The method according to claim 1 , wherein the panel is a floor panel.

11 . The method according to claim 1 , wherein the carrier is a wood based core.

12 . A building panel comprising a decorative surface layer connected to a core wherein the surface layer is a mix comprising fibres, coloring substance, a binder and wear resistant particles, and wherein the surface layer comprises lower parts and upper parts, wherein there is a binder concentration gradient between the lower parts and upper parts.

13 . The building panel according to claim 12 , wherein the lower parts comprises less binder than the upper parts.

14 . The building panel according to claim 12 , wherein the upper parts comprises less binder than the lower parts.

15 . The building panel according to any claim 12 , wherein the binder is a melamine resin.

16 . The building panel according to claim 12 , wherein the fibres are wood fibres.

17 . The building panel according to claim 12 , wherein the panel is floor panel

18 . A method of manufacturing a building panel having plain coloured surface whereby the method comprises the steps of:

applying a layer comprising a mix of fibres, binder, wear resistant particles, and a coloring substance, on a carrier wherein the mix is floatable under heat and pressure; and

applying heat and pressure on the mix,

wherein the mass ratio between resins and fibres is less than about 90%.

19 . The method of manufacturing a building panel according to claim 18 , wherein the mass ratio between the binder and the sum of the masses of the fibres and the coloring substances is higher than about 60%.

20 . A method of manufacturing a building panel having plain coloured surface whereby the method comprises the steps of:

applying a layer comprising a mix of fibres, binder, wear resistant particles, and a coloring substance, on a carrier wherein the mix is floatable under heat and pressure; and

applying heat and pressure on the mix,

wherein the mass ratio between the binder and the sum of the masses of the fibres and the coloring substances is higher than about 60%.

21 . The method according to 20 , wherein the binder is a resin.

23 . A building panel produced according to the method of claim 20 .