Laminated sheets prod - core has number of hollow projections

摘要

Laminate comprises a core consisting of a thermoplastic or glass cuspated sheet consisting of a series of hollow projections from each face of the median plane of the sheets. The outer tips of the projections on the ends furthest from the median plane are closed and the ends of the projections in the median plane are open. The projections form a series of pointed cusps and the core is laminated to a porous sheet. The points of the cusps on at least one face have been melted and at least partially allowed to impregnate the porous sheet and a facing sheet is fixed to the porous sheet.