Method of forming a digital print with dry powder
A method and equipment to form a digital print by applying dry colourants on a surface of a panel, bonding a part of the colourants with a binder and removing the non-bonded colourants from the surface. The method of forming a digital print on a surface of a panel includes displacing the panel under a digital drop application head, applying a liquid binder with the digital drop application head on the surface; applying colourants on the liquid binder and the surface; bonding a part of the colourants to the surface with the liquid binder; removing non-bonded colourants from the surface such that a digital print is formed by the bonded colourants; and applying heat and pressure on the panel, the surface and the bonded colorants such that the colourants are permanently bonded to the surface.
1. A method of forming a digital print on a surface of a building panel, wherein the surface is a powder layer comprising a binder, the method comprising:
applying a liquid substance on the surface;
applying a dry powder on the liquid substance and the surface;
bonding a part of the dry powder to the surface with the liquid substance; and
removing non-bonded dry powder from the surface such that a digital print is formed by the bonded dry powder.
2. The method as claimed in claim 1 , wherein the powder layer further comprises fibers or wood fibres.
3. The method as claimed in claim 1 , wherein the powder layer further comprises pigments.
4. The method as claimed in claim 1 , wherein the binder in the powder layer comprises resins.
5. The method as claimed in claim 1 , wherein the binder in the powder layer comprises thermosetting resins.
6. The method as claimed in claim 1 , wherein the binder in the powder layer comprises melamine formaldehyde resins.
7. The method as claimed in claim 1 , wherein the binder in the powder layer comprises a thermoplastic material.
8. The method as claimed in claim 1 , wherein the liquid substance is transparent.
9. The method as claimed in claim 1 , wherein the liquid substance is water based.
10. The method as claimed in claim 1 , wherein the liquid substance comprises ethylene glycol.
11. The method as claimed in claim 1 , wherein the liquid substance comprises at least 75 wt % of ethylene glycol.
12. The method as claimed in claim 1 , wherein no resins are provided in the liquid substance.
13. The method as claimed in claim 12 , wherein no pigments are provided in the liquid substance.
14. The method as claimed in claim 1 , wherein no pigments are provided in the liquid substance.
15. The method as claimed in claim 1 , wherein the liquid substance comprises a viscosity increasing substance.
16. The method as claimed in claim 1 , wherein the powder layer is stabilized.
17. The method as claimed in claim 1 , wherein the dry powder comprises colorants comprising pigments.
18. The method as claimed in claim 17 , wherein the colorants comprise a wood fibre, a mineral particle, or a spray-dried resin.
19. The method as claimed in claim 1 , wherein the dry powder is applied by scattering.
20. The method as claimed in claim 1 , further comprising applying heat on the surface and the bonded dry powder.
21. The method as claimed in claim 1 , wherein the liquid substance is applied on the surface with a digital drop application head.
22. The method as claimed in claim 1 , wherein the building panel is a floor panel.