Accoustical Absorption Coating and Process

Abstract

A process for dampening sound and a material for effecting that process have been developed. The process involves applying multiple layers of a coating that then transmits that sound into very small cavities. These cavities perform several functions, they further transmit the sound, they absorb some of the sound through the random cancellation of reflecting waves, and they contain sound attenuation media such as closed cell cavities and projection particles. The projection particles act in at least two ways, they perform a baffling function, and they act as sympathetic resonators. The material which has been developed to effect this process consists of a lattice structure with vacant and non vacant cavities. The non-vacant cavities contain structures and mechanisms for altering, redirecting, reflecting, and absorbing the incident acoustical waves. The invention may be extended to hot gas environments and electrically and thermally conductive surface coating applications.

1 . A sound attenuation material which comprises; A Lattice structure; said lattice structure comprising a substantially continuous framework; said framework having vacant and non vacant cavities; said structure further chemically or mechanically retaining a plurality of mechanisms for altering, attenuating, reflecting, or absorbing sound; material further comprising Projection surfaces mechanisms for projecting acoustical waves towards absorbing or attenuating means; further said projection mechanisms being retained by said lattice structure material further comprising Absorber or attenuation means  
   
   
       2 . A sound attenuation material as in  claim 1  where lattice structure is primarily resin based  
   
   
       3 . A sound attenuation material as claimed in  claim 1  where said lattice structure is completely inorganic in composition  
   
   
       4 . An article of manufacture as claimed in  claim 1  where said lattice structure is reinforced with thermal conduction means.  
   
   
       5 . A sound attenuation material as claimed in  claim 1  where Said Projection surfaces are composed of a a plurality of plate like ceramic particles selected from the group of platelet clays, platelet talcs, mica, or plate like zirconium carbide.  
   
   
       6 . A sound attenuation material as claimed in  claim 1  where said projection surfaces are composed of one of the following group: platelet clays, platelet talcs, mica, or other ceramic particles available in platelet form.  
   
   
       7 . A sound attenuation material as claimed in  claim 1  where said absorber means comprises ceramic microspheres;  
   
   
       8 . A sound attenuation material as claimed in  claim 7  where said absorber means additionally comprising extended stub tuning apparatus where such stub tuners are extended into vacant areas defined within said lattice structure; said stub tuners further being non uniform in extended length  
   
   
       9 . A sound attenuation material as claimed in  claim 8  where said stub tuner means are composed of ceramic particles having a high aspect ratio in at least two of three dimensions such as rods or plates.  
   
   
       10 . A sound attenuation material as claimed in  claim 1  where said material additionally comprising crack propagation resistance means;  
   
   
       11 . An article of manufacture as claimed in  claim 10  where said crack resistance means is thermally conductive  
   
   
       12 . An article of manufacture as claimed in  claim 10  where said crack resistance means are electrically conductive  
   
   
       13 . A sound attenuation material as claimed in  claim 10  where said crack propagation resistance means consists of fibrous reinforcement; said fibrous reinforcement also possessing sound attenuation properties.  
   
   
       14 . An article of manufacture as claimed in  claim 1  where said lattice structure is electrically conductive  
   
   
       15 . An article of manufacture as claimed in  claim 1  where one or a plurality of components including the lattice, the acoustical reflectors, and the acoustical absorbers are electrically conductive  
   
   
       16 . A Process for dampening sound involving the application of multiple layers of a coating comprising: for transmitting sound incident upon a surface; for Absorbing sound once it has been transmitted into the cavities of a coatings first absorbing portion; a second absorbing portion where said incoming sound is further transmitted said sound transmission surfaces being situated directly after said second absorbing portion; Said second absorbing portion being substantially comprised of closed cell cavities in which incoming sound is damped by its own reflection and a plurality of sound attenuation media for absorbing acoustical energy;  
   
   
       17 . A process for dampening sound as claimed in  claim 16  where said means for transmitting sound is a porous layer of loosely bound ceramic said loosely bound ceramic forming a non continuous highly porous first coating layer.  
   
   
       18 . A process for dampening sound as claimed in  claim 17  wherein said non continuous highly porous first coating layer also comprises sound redirection means  
   
   
       19 . A process for dampening sound as claimed in  claim 18  wherein said redirection means comprises plate or rod like structures;  
   
   
       20 . A process for dampening sound as claimed in  claim 19  wherein said plate or rod like structures substantially act as sympathetic resonators  
   
   
       21 . A process for dampening sound as claimed in  claim 18  wherein said plate or rod like structures substantially perform a baffling function.  
   
   
       22 . A process for dampening sound as claimed in  claim 18  where said plate or rod like structures are comprised of various forms of plate like kaolin and talc.  
   
   
       23 . A process for dampening sound as claimed in  claim 16  where said means for absorbing sound in said first absorbing portion is effected by the use of hollow ceramic particles as resonant cavities.  
   
   
       24 . A process for dampening sound as claimed in  claim 16  where said means for absorbing sound in said first absorbing portion is effected by the use of baffles formed by the positioning within said transmission means of particles performing a baffling function.  
   
   
       25 . A process for dampening sound as claimed in  claim 16  where said second absorbing portion is comprised of a porous structure with adhesive bonding means substantially integral with network formation means; said adhesive bonding means causing attachment of said second absorbing layer to a surface;  
   
   
       26 . A process for dampening sound as claimed in  24  where said surface is required to be acoustically reflective;  
   
   
       27 . A process for dampening sound as claimed in  claim 24  where said surface may additionally provide sound attenuation means;  
   
   
       28 . A process for dampening sound as claimed in  claim 16  where said second absorbing layer is comprised of any number of a plurality of substantially equivilent layers;  
   
   
       29 . A Process as claimed in  claim 16  where said lattice work enables the damping of sound in a hot gas environment  
   
   
       30 . A process as claimed in  claim 16  where one or a plurality of components including the lattice, the acoustical reflectors, and the acoustical absorbers exhibit electrical conductivity.  
   
   
       31 . A process as claimed in  claim 16  where the process additionally involves the resistance of mildew growth by application means which retains sufficient porosity to enable a permeability rating.  
   
   
       32 . A process as claimed in  claim 16  wherein the process additionally involves a resistance to flame spread  
   
   
       33 . A process as claimed in  claim 16  wherein said incident acoustical energy is alternately transformed into electrical energy through the auspices of a piezoelectric material such as barium titanate.