Ex Parte Andre et al - Page 2

                 Appeal No. 2007-0886                                                                                  
                 Application 09/914,181                                                                                
                        Appellants’ invention relates to a process for producing an acoustical                         
                 attenuating panel for use, for example, in the attenuation of noise arising                           
                 from aircraft turbo motors (Specification 1:5-10).  The panel has four main                           
                 parts positioned in the following order:  a layer with structural properties, a                       
                 layer with acoustical properties, a cellular structure and a reflector (Br. 2).                       
                 The first two layers form a single sheet after polymerization and are referred                        
                 to collectively as the “acoustically resistive layer.”                                                
                        Independent claim 9 is illustrative of the invention:                                          
                        9.  Process for the production of an acoustical attenuating panel                              
                 comprising a cellular structure covered on one side with a reflector and on                           
                 the other side with an acoustically resistive layer with two components                               
                 respectively with an acoustical property and with a structural property,                              
                 which process comprises the following steps:                                                          
                        - emplacing on a mold of a shape appropriate to the panel to be                                
                 obtained, a layer with structural properties, constituted by filaments pre-                           
                 impregnated with a thermoplastic or thermosetting resin, by draping,                                  
                 winding or wrapping said filaments while spacing the latter, such that said                           
                 layer has a quantity of open surface of the order of 30% of the total surface                         
                 of the exposed layer,                                                                                 
                        - emplacing from above the layer with structural properties, a layer                           
                 with acoustical properties, constituted by a microporous cloth of mineral or                          
                 organic fibers a thickness of the order of a tenth of that of the layer with                          
                 structural properties;                                                                                
                        - then emplacing the cellular structure and the reflector, and                                 
                        - performing at least one step of baking in an autoclave at the end of at                      
                 least one of the said steps of emplacing.                                                             





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