Moisture barrier coatings

Abstract

A barrier assembly having a flexible or rigid substrate overcoated with an all polymer multilayer stack. A multilayer on the substrate includes alternating diamond-like glass or carbon layers with polymer layers. Another multilayer includes alternating polymer layers using different types of polymers. The barrier layers can be used to mount, cover, encapsulate or form composite assemblies for protection of moisture or oxygen sensitive articles

1 . A composite assembly for protection of a moisture or oxygen sensitive article, comprising: 
 a substrate;    a first polymer layer overcoated on the substrate; and    a second polymer layer overcoated on the first polymer layer,    wherein the first polymer layer is composed of a first polymer and the second polymer layer is composed of a second polymer different from the first polymer, and wherein the second polymer comprises a plasma polymer.    
   
   
       2 . The assembly of  claim 1 , wherein the substrate comprises a rigid material or a flexible material.  
   
   
       3 . The assembly of  claim 1 , wherein the first polymer layer comprises a plasma polymer.  
   
   
       4 . The assembly of  claim 1 , wherein the first polymer layer comprises a UV cured acrylate.  
   
   
       5 . The assembly of  claim 1 , wherein the second polymer layer overcoated on the first polymer layer comprises a dyad and wherein the assembly has a plurality of the dyads overcoated on the substrate.  
   
   
       6 . The assembly of  claim 5 , further comprising an additional layer between at least two of the dyads.  
   
   
       7 . A composite assembly for protection of a moisture or oxygen sensitive article, comprising: 
 a substrate;    a polymer layer overcoated on the substrate; and    a diamond-like carbon layer overcoated on the polymer layer.    
   
   
       8 . The assembly of  claim 7 , wherein the substrate comprises a rigid material or a flexible material.  
   
   
       9 . The assembly of  claim 7 , wherein the diamond-like carbon layer comprises a coating comprising approximately 50 to 90 atomic percent carbon and approximately 10 to 50 atomic percent hydrogen, with a gram atom density of between approximately 0.20 and approximately 0.28 gram atoms per cubic centimeter, and composed of approximately 50 to approximately 90% tetrahedral bonds.  
   
   
       10 . The assembly of  claim 7 , wherein the polymer layer overcoated on the diamond-like carbon layer comprises a dyad and wherein the assembly has a plurality of the dyads overcoated on the substrate.  
   
   
       11 . The assembly of  claim 10 , further comprising an additional layer between at least two of the dyads.  
   
   
       12 . A composite assembly for protection of a moisture or oxygen sensitive article, comprising: 
 a substrate;    a polymer layer overcoated on the substrate; and    a diamond-like glass layer overcoated on the polymer layer.    
   
   
       13 . The assembly of  claim 12 , wherein the substrate comprises a rigid material or a flexible material.  
   
   
       14 . The assembly of  claim 12 , wherein the diamond-like glass layer comprises an at least substantially amorphous glass including carbon and silicon.  
   
   
       15 . The assembly of  claim 14 , wherein the diamond-like glass layer further comprises one or more components selected from the group including hydrogen, nitrogen, oxygen, fluorine, sulfur, titanium, and copper.  
   
   
       16 . The assembly of  claim 12  wherein the diamond-like glass layer comprises an oxygen depleted layer having an oxygen to silicon ratio of less than approximately 1.5.  
   
   
       17 . The assembly of  claim 12 , wherein the polymer layer overcoated on the diamond-like glass layer comprises a dyad and wherein the assembly has a plurality of the dyads overcoated on the substrate.  
   
   
       18 . The assembly of  claim 17 , further comprising an additional layer between at least two of the dyads.  
   
   
       19 . The assembly of  claim 12 , wherein the diamond-like glass layer, when approximately one micron thick, is at least 70% transmissive to radiation at substantially all wavelengths from about 400 nm to about 800 nm.  
   
   
       20 . A process for fabricating a composite assembly for protection of a moisture or oxygen sensitive article, comprising: 
 providing a substrate;    overcoating a first polymer layer on the substrate; and    overcoating a second polymer layer on the first polymer layer,    wherein the first polymer layer is composed of a first polymer and the second polymer layer is composed of a second polymer different from the first polymer.    
   
   
       21 . The process of  claim 20 , further comprising performing the step of overcoating the second polymer layer in an environment having a pressure of less than 10 mTorr and a substrate bias of greater than 500 V.  
   
   
       22 . The process of  claim 20 , wherein the overcoating the second polymer step includes overcoating a plasma polymer.  
   
   
       23 . A process for fabricating a composite assembly for protection of a moisture or oxygen sensitive article, comprising: 
 providing a substrate;    overcoating a polymer layer on the substrate; and    overcoating a diamond-like carbon layer on the polymer layer.    
   
   
       24 . The process of  claim 23 , further comprising performing the step of overcoating the polymer layer in an environment having a pressure of less than 10 mTorr and a substrate bias of greater than 500 V.  
   
   
       25 . A process for fabricating a composite assembly for protection of a moisture or oxygen sensitive article, comprising: 
 providing a substrate;    overcoating a polymer layer on the substrate; and    overcoating a diamond-like glass layer on the polymer layer.    
   
   
       26 . The process of  claim 25 , further comprising performing the step of overcoating the polymer layer in an environment having a pressure of less than 10 mTorr and a substrate bias of greater than 500 V.  
   
   
       27 . The process of  claim 25 , wherein the step of overcoating the diamond-like glass layer comprises overcoating an oxygen depleted layer having an oxygen to silicon ratio of less than approximately 1.5.