Laminate production method
A method for producing an impregnated article comprising a cellulose layer which is impregnated with a melamine resin in order for a core impregnation to be formed is characterized in that a layer of a liquid medium having a moiety of isocyanate groups is applied to the top face and/or the bottom face of the core-impregnated cellulose layer.
1. A process for the production of a cellulose ply comprising:
impregnating a core of the cellulose ply with a melamine resin to form a core-impregnation cellulose ply; and
applying a layer made of a liquid medium having a proportion of isocyanate groups to at least one of an upper side and underside of the core-impregnated cellulose ply wherein the isocyanate groups react with either a α-cellulose in the core-impregnated cellulose ply or with the melamine resin.
2. The process as claimed in claim 1 , wherein the liquid medium is applied in the form of dispersion with from 50% to 60% solids content, the remainder being water, and is then dried to give a layer.
3. The process as claimed in claim 1 , wherein the liquid medium is applied in the form of heated hotmelt with 100% solids content and the isocyanate groups, and during the subsequent cooling spontaneously forms a layer.
4. The process as claimed claim 1 , wherein the liquid medium comprises wear-inhibiting particles.
5. The process as claimed in claim 1 , wherein a quantity of the liquid medium is from 50 g/m 2 to 300 g/m 2 .
6. The process as claimed claim 1 , wherein at least one protective covering layer is applied to the layer on the upper side.
7. The process as claimed in claim 6 , wherein the protective covering layer comprises nanoparticles to improve resistance to microscratching, and/or agents having antistatic effect and/or agents having antibacterial effect provided.
8. The process as claimed in claim 1 , wherein the melamine resin takes the form of mixture of melamine resin and urea resin.
9. The process as claimed in claim 4 , wherein the liquid medium comprises corundum particles.
10. The process as claimed in claim 1 , wherein the isocyanate groups react either with OH group of the α-cellulose in the cellulose ply or with a NH group or a methylol group of the melamine resin of the core-impregnation system of the cellulose ply.
11. The process as claimed in claim 10 , wherein solids content of the liquid medium is from 50% to 60%, with water as solvent.
12. The process as claimed in claim 10 , wherein solids content of the liquid medium is from 50% to 60%, with organic solvents or additions.
13. The process as claimed in claim 12 , wherein the organic solvents or additions are one of dispersing agents, release agents, wetting agents, and antifoams.
14. The process as claimed in claim 3 , wherein prior to the hotmelt being applied to the core-impregnated cellulose ply, the liquid medium is heated and melted and the hotmelt is applied either by using a slot die or by spray application.
15. The process as claimed in claim 3 , further comprising applying to an upper side of a dried layer of the liquid medium, or of re-hardened hotmelt, at least one protective covering layer composed of a UV lacquer, which comprises admixed nanoparticles.
16. The process as claimed in claim 10 , wherein the melamine resin is pure melamine resin.
17. The process as claimed in claim 10 , wherein the melamine resin is a melamine resin mixture made of pure melamine resin and urea resin.