Reinforced foam in sheet form

Claim 1

A FLEXIBLE FOAMED PLASTIC PRODUCT COMPRISING A UNITARY SINGLE SHEET OF FLEXIBLE PLASTIC FOAM OF SUBSTANTIALLY UNIFORM THICKNESS AND GREAT BREADTH AND LENGTH RELATIVE TO ITS THICKNESS, SAID SHEET HAVING A UNITARY AND CONTINUOUS CELLULAR STRUCTURE THROUGHOUT WITH A RELATIVELY COARSE-PORE INTERNAL STRUCTURE THROUGHOUT ITS THICKNESS EXCEPT IMMEDIATELY ADJACENT ITS BROAD SURFACE FACES AND HAVING AT SUCH FACES A SKIN OF RELATIVELY FINE-PORE STRUCTURE INTEGRAL WITH SAID INTERNAL STRUCTURE AND FORMING A SUBSTANTIALLY SMOOTH CONTINUOUSLY ENVEN INTEGRAL SUFACE FILM RESISTANT TO PENETRATION OF SURFACE COATINGS APPLIED THERETO AND A FLEXIBLE DISCONTINUOUS REINFORCING LAYER COMPRISING SPACED FILAMENTARY REINFORCING ELEMENTS DISPOSED WITHIN SAID SHEET BETWEEN AND SUBSTANTIALLY PARALLEL TO THE BROAD FACES THEREOF, THE BODY OF SAID SHEET BEING FOAMED IN SITU INTEGRALLY THROUGH THE INTERSTICES BETWEEN SAID REINFORCING ELEMENTS AND POSSESSING SUBSTANTIALLY THE SAME PORE STRUCTURE WITHIN SUCH INTERSTICES AS ON THE OPPOSITE SIDES OF THE REINFORCING ELEMENTS.