Fire door core assembly

Abstract

A laminated fire door including a core, containing panels or boards made from an organic material including flax, and a fibrous binder constituting a sodium silicate adhesive, is used to make a door exhibits at least a 45 minute fire rating. In accordance with a preferred form of the invention, the fire door core is formed by using a silicate adhesive, preferably sodium silicate, in the order of 25 mils (0.6 mm) to laminate together two flax boards, each having a thickness in the range of 0.625-0.875 inches (approximately 16-22 mm), with each of the laminated flax boards having a density of between 20 and 45 pounds per cubic foot (320-700 kgs/m 3 ).

1 . A fire door comprising: 
 an outer peripheral frame; and    a two panel laminate core including: 
 a first panel formed from an organic material including first and second opposing planar surfaces, said organic material including flax;  
 a second panel formed from an organic material including first and second opposing planar surfaces, said organic material including flax; and  
 a fibrous binder layer arranged between the first planar surface of the first panel and the first planar surface of the second panel, said binder layer including a silicate adhesive, wherein the first and second panels are pressed together with the binder layer sandwiched therebetween to form the two panel laminate core, said two panel laminate core being arranged within the outer peripheral frame to form a door having a fire rating of at least 45 minutes.  
   
   
   
       2 . The fire door according to  claim 1 , wherein each of the first and second panels has a thickness in the order of 0.625-0.875 inches (approximately 16-22 mm).  
   
   
       3 . The fire door according to  claim 1 , wherein the flax in the first and second panels has a density between 20 and 45 pounds per cubic foot (320-700 kgs/m 3 ).  
   
   
       4 . The fire door according to  claim 1 , wherein the fibrous binder layer is approximately 25 mils (approximately 0.6 mm) thick.  
   
   
       5 . The fire door according to  claim 1 , wherein the silicate adhesive constitutes sodium silicate.  
   
   
       6 . The fire door according to  claim 5 , wherein the sodium silicate further contains components selected from the group consisting of: talc, aluminum silicate of potash and soda, magnesium silicate, cellulose and/or inert fillers, kaolin clay, mica, perlite and/or cristaline silica.  
   
   
       7 . A two panel laminate core for a fire resistant door having a fire rating of at least 45 minutes including: 
 a first panel formed from an organic material including first and second opposing planar surfaces, said organic material including flax;    a second panel formed from an organic material including first and second opposing planar surfaces, said organic material including flax; and    a fibrous binder layer arranged between the first planar surface of the first panel and the first planar surface of the second panel, said binder layer including a silicate adhesive, wherein the first and second panels are pressed together with the binder layer sandwiched therebetween to form the two panel laminate core, said two panel laminate core being arranged within the outer peripheral frame to form a door having a fire rating of at least 45 minutes.    
   
   
       8 . The core according to  claim 7 , wherein each of the first and second panels has a thickness in the order of 0.625-0.875 inches (approximately 16-22 mm).  
   
   
       9 . The core according to  claim 7 , wherein the flax in the first and second panels has a density between 20 and 45 pounds per cubic foot (320-700 kgs/m 3 ).  
   
   
       10 . The core according to  claim 7 , wherein the fibrous binder layer is approximately 25 mils (approximately 0.6 mm) thick.  
   
   
       11 . The core according to  claim 7 , wherein the silicate adhesive constitutes sodium silicate.  
   
   
       12 . The core according to  claim 11 , wherein the sodium silicate further contains components selected from the group consisting of: talc, aluminum silicate of potash and soda, magnesium silicate, cellulose and/or inert fillers, kaolin clay, mica, perlite and/or cristaline silica.  
   
   
       13 . A method of forming a two panel fire resistant door core rated for at least 45 minutes comprising: 
 forming a first panel formed from an organic material containing flax;    forming a second panel formed from an organic material containing flax;    coating one side of at least one of the first and second panels with a silicate adhesive to form a binder layer; and    joining the first and second panels with the binder layer being sandwiched between the first and second panels.    
   
   
       14 . The method of  claim 13 , wherein joining the first and second panels constitutes cold pressing the first and second panels together to a desired thickness for the laminate core.  
   
   
       15 . The method of  claim 13 , further comprising: 
 mounting the core in an outer peripheral frame; and    applying outer sheathing panels to opposite sides of the core to form a door having a fire rating of at least  45  minutes.    
   
   
       16 . The method of  claim 13 , wherein the binder layer is rolled onto each of the first and second panels.  
   
   
       17 . The method of  claim 13 , wherein each of the first and second panels is provided with a thickness in the order of 0.625-0.875 inches (approximately 16-22 mm).  
   
   
       18 . The method of  claim 13 , wherein the binder layer is formed approximately 25 mils (approximately 0.6 mm) thick.  
   
   
       19 . The method of  claim 13 , wherein the silicate adhesive constitutes sodium silicate.  
   
   
       20 . The method of  claim 19 , further comprising: employing sodium silicate which contains components selected from the group consisting of: talc, aluminum silicate of potash and soda, magnesium silicate, cellulose and/or inert fillers, kaolin clay, mica, perlite and/or cristaline silica.