Planks and/or boards

Abstract

A board comprises a front, a back, a first longitudinal side; and a second longitudinal side; at least one of said longitudinal sides comprising a groove to facilitate the junction to another such board; wherein said board incorporates a backing layer of primarily rigid plastics material and a further layer located over said backing layer on said front being primarily of an elastomer; said elastomer extending only over said front.

1 . A board comprising:
 a front, a back, a first longitudinal side; and   a second longitudinal side; at least one of said longitudinal sides comprising a groove to facilitate the junction to another such board;   wherein said board incorporates a backing layer of primarily rigid plastics material and a further layer located over said backing layer on said front being primarily of an elastomer;   said elastomer extending only over said front.   
     
     
         2 . A board according to  claim 1 , wherein said rigid plastics material of said backing material is a rigid foam. 
     
     
         3 . A board according to  claim 1 , wherein said groove exposes rigid foamed plastics material. 
     
     
         4 . A board according to  claim 2 , wherein said layer of primarily rigid foamed plastics material has a shore D hardness of 35 to 75. 
     
     
         5 . A board according to  claim 1 , wherein said further layer has a shore A hardness of 20 to 90. 
     
     
         6 . A board according to  claim 1 , wherein said further layer has a shore A hardness of more than 35 and less than 90. 
     
     
         7 . A board according to  claim 1 , wherein said further layer is an inherently flexible layer. 
     
     
         8 . A board according to  claim 2 , wherein said layer of primarily rigid foamed plastics material is primarily polyurethane. 
     
     
         9 . A board according to  claim 8 , wherein said layer of primarily rigid foamed plastics material incorporates 20 to 50% fillers by weight. 
     
     
         10 . A board according to  claim 9 , wherein said fillers comprise one or more from the group consisting of: ground glass, pulverised fuel ash (PFA), and fibres. 
     
     
         11 . A board according to  claim 2 , wherein said layer of primarily rigid foamed plastics material incorporates reinforcing fibres. 
     
     
         12 . A board according to  claim 11 , wherein said layer of primarily rigid foamed plastics material incorporates glass reinforcing fibres. 
     
     
         13 . A board according to  claim 11 , wherein said layer of primarily rigid foamed plastics material incorporates a rice based fibre. 
     
     
         14 . A board according to  claim 2 , wherein said layer of primarily rigid foamed plastics material incorporates 30 to 60% air by volume. 
     
     
         15 . A board according to  claim 1 , wherein said further layer is primarily of polyurethane elastomer. 
     
     
         16 . A board according to  claim 1 , where said further layer is primarily of polyurea. 
     
     
         17 . A board according to  claim 15 , wherein said polyurethane elastomer incorporates no air bubbles. 
     
     
         18 . A board according to  claim 15 , wherein said polyurethane elastomer incorporates at least one filler selected from the group comprising ground glass, water scavengers, liquid fire retardants, powder fire retardants, recycled rubber, minerals and pulverised fuel ash (PFA). 
     
     
         19 . A board according to  claim 1 , further comprising a coating provided over said further layer; said coating being at least in part an aliphatic isocyanate. 
     
     
         20 . A board according to  claim 1 , wherein said backing layer and said further layer are chemically cross-linked; thereby no separate adhesive links one layer to the other. 
     
     
         21 . A board according to  claim 19 , wherein said coating and said further layer are chemically cross-linked; thereby no separate adhesive links one layer to the other. 
     
     
         22 . A board according to  claim 1 , wherein at least said further layer is homogeneous. 
     
     
         23 . A board according to  claim 1 , wherein said backing layer and said further layer act as an adhesive to one another. 
     
     
         24 . A board according to  claim 1 , further comprising multiple lateral projections on at least one longitudinal side of the board and recesses on at least one opposite longitudinal side of the board for mating engagement with the lateral projections of another board. 
     
     
         25 . A board according to  claim 1 , wherein said board is a cladding board. 
     
     
         26 . A moulding process of producing a board, comprising the steps of selecting a mould for forming a board with a side with a groove to facilitate the attachment of the board to another such board;
 forming a layer which is primarily of an elastomer;   forming a backing layer which is primarily of rigid foamed plastics material; and   preventing said groove from being covered by said elastomer.   
     
     
         27 . A method according to  claim 26 , comprising the step of starting the moulding process with an in-mould coating of aliphatic isocyanate based medium.