摘要:
The present concerns a method for coating inflexible board type and predominantly wooden products (1) with a thermoplastic polymer. The method comprises extruding a molten thermoplastic polymer (T) from a die gap (2) for a molten coating film (4), which is conducted onto a product top surface of the coatable product across a line pressure point (13). The die gap lies at a distance (Q) from the line pressure point (13). The method further comprises allowing said molten coating film (4) to be in surface contact with a product top surface (5y), said surface contact being sustained by means of a surface compression generated by a static and/or dynamic pressure load (P) from a flowing medium (G) and directed towards the top surface (5y), and allowing said flowing medium to cool the coating film (4) of thermoplastic polymer from molten form to solid form while sustaining the surface compression generated by said static and/or dynamic pressure load (P).
摘要:
The invention concerns a coating apparatus for coating inflexible board type and predominantly wooden products (1) with a thermoplastic polymer. The coating apparatus comprises an extrusion die (9), which delivers a thermoplastic polymer (T) as a molten coating film (4) onto a product top surface (5y) of the product across a line pressure point (13) at a distance (Q) from the line pressure point, and supporting rolls (18a) and/or supporting rollers (18b) and/or one or more flat blocks (19) establishing a supporting platform (K), as well as a cooling section (15). The cooling section comprises a press belt (3) extending around rolls (20y and 12 or 11 and 12) set at a distance (L2) from each other and running co-directionally with the coatable product's length (L1); and between the rolls at least one cooling block (8) and/or press rolls (18) or press rollers (19), as well as compression elements (17) which are adapted to push at least some of the press rolls or the press rollers or the cooling blocks towards the supporting platform (K) with such a force (F) which generates with the press belt a pressure load (P) between the coating film (4) and the product top surface (5y), thus sustaining their mutual surface contact.