Patent ID: 8511429
Filing Date: 2013-08-20
Classification: E04B

Abstract:
1. An acoustical ceiling panel comprising a flat core and an acoustically transparent face sheet adhesively attached to one of two oppositely facing major sides of the core, the core comprising a multitude of layers of corrugated fiberboard laminated together, the corrugated fiberboard layers each having a corrugated medium adhesively attached to a flat liner board, the corrugated medium forming regularly spaced flutes of curvilinear cross-section, sidewalls of the flutes being perpendicular to the face sheet, the flutes of the layers of fiberboard being arranged in parallel directions extending perpendicularly to the major faces of the core, the core having major face dimensions of 2 foot by 2 foot or 2 foot by 4 foot and a nominal thickness of about 1 inch, the face sheet being a non-woven scrim painted to achieve an air flow resistance that allows the panel to exhibit an NRC of about 0.7.