In-line coated wood-based boards

1. A wood-based board comprising

a) a base of wood particles and/or fibres, and

b) a coating on the first and/or reverse side of the wood-based board, wherein the coating comprises

i) at least one particulate filler material, having a ratio of particle size d 80 to particle size d 20 [d 80 /d 20 ] from 0.5 to 1.0, and

ii) at least one binder.

2. The wood-based board according to claim 1 , wherein the coating is penetrated into the surface of the wood-based board.

3. The wood-based board according to claim 1 , wherein the at least one particulate filler material has

i) a particle size d 98 of <500 μm,

ii) a particle size d 80 of 0.1 to 250 μm,

iii) a median particle size d 50 of 0.1 to 150 μm, and

iv) a particle size d 20 of 0.1 to 50 μm.

4. The wood-based board according to claim 1 , wherein the surface of the coated side of the wood-based board has

i) a brightness from 50 to 100%, according ISO R457 (Tappi452) and DIN 6167,

ii) a yellowness from 2 to 70%, according ISO R457 (Tappi452) and DIN 6167,

iii) L* from 50 to 100, according to DIN EN ISO 11664-4:2012,

iv) a* from −5 to 10, according to DIN EN ISO 11664-4:2012, and

v) b* from 0 to 30, according to DIN EN ISO 11664-4:2012.

5. The wood-based board according to claim 1 , wherein the surface of the coated side of the wood-based board has

i) a maximum roughness amplitude Sz from 20 to 800 μm,

ii) an arithmetic mean roughness Sa from 2 to 80 μm, and

iii) a root mean square roughness Sq from 2 to 20 μm.

6. The wood-based board according to claim 1 , wherein the at least one particulate filler material has

i) a particle size d 98 of <500 μm,

ii) a particle size d 80 of 0.1 to 250 μm,

iii) a median particle size d 50 of 0.1 to 150 μm, and

iv) a particle size d 20 of 0.1 to 50 μm,

and the surface of the coated side of the wood-based board has

i) a brightness from 50 to 100%, according ISO R457 (Tappi452) and DIN 6167,

ii) a yellowness from 2 to 70%, according ISO R457 (Tappi452) and DIN 6167,

iii) L* from 50 to 100, according to DIN EN ISO 11664-4:2012,

iv) a* from −5 to 10, according to DIN EN ISO 11664-4:2012, and

v) b* from 0 to 30, according to DIN EN ISO 11664-4:2012, and

i) a maximum roughness amplitude Sz from 20 to 800 μm,

ii) an arithmetic mean roughness Sa from 2 to 80 μm, and

iii) a root mean square roughness Sq from 2 to 20 μm.

7. The wood-based board according to claim 1 , wherein the wood-based board further comprises a printing on the first and/or reverse side of the wood-based board on the coating of the wood-based board.

8. The wood-based board according to claim 1 , wherein the wood-based board is a fibre board product comprising a high-density fibre (HDF) board, medium-density fibre (MDF) board, low-density fibre (LDF) board, a particle board, an oriented strandboard (OSB), a hardboard or an insulation board.

9. The wood-based board according to claim 1 , wherein the wood-based board has a bending strength of >5 N/mm 2 .

10. The wood-based board according to claim 1 , wherein the wood-based board has a bending strength of 10 to 50 N/mm 2 .

11. The wood-based board according to claim 1 , wherein the wood-based board has a bending strength of 15 to 45 N/mm 2 .

12. The wood-based board according to claim 1 , wherein the wood-based board has a modulus of elasticity of >500 N/mm 2 .

13. The wood-based board according to claim 1 , wherein the wood-based board has a modulus of elasticity from 1 000 to 4 500 N/mm 2 .

14. The wood-based board according to claim 1 , wherein the wood-based board has a modulus of elasticity from 1 500 to 3 500 N/mm 2 .

15. The wood-based board according to claim 1 , wherein the wood-based board has an internal bond strength of >0.10 N/mm 2 .

16. The wood-based board according to claim 1 , wherein the wood-based board has an internal bond strength of 0.2 to 1.4 N/mm 2 .

17. The wood-based board according to claim 1 , wherein the wood-based board has an internal bond strength of 0.4 to 1.2 N/mm 2 .

18. The wood-based board according to claim 1 , wherein the wood-based board has a thickness swelling after 24 h water storage of <20%.

19. The wood-based board according to claim 1 , wherein the wood-based board has a thickness swelling after 24 h water storage from 2.0 to 15.0%.

20. The wood-based board according to claim 1 , wherein the wood-based board has a thickness swelling after 24 h water storage from 4.0 to 10%.

21. The wood-based board according to claim 1 , wherein the wood-based board has a brightness of at least 50%.

22. The wood-based board according to claim 1 , wherein the wood-based board has a brightness of at least 65%.

23. The wood-based board according to claim 1 , wherein the wood-based board has a brightness of at least 75%.

24. The wood-based board according to claim 1 , wherein the wood-based board has a brightness of at least 80%.