Transparent plastic optical components and abrasion resistant polymer substrates and methods for making the same

Abstract

A polymer-based component formed from a synthetic thermoplastic or thermoset resin substrate, such as polymethyl methacrylate, which is resistant to warping and distortion from moisture. A composite multi-layer surface-hardening coating is formed on at least the anterior surface of the resin substrate. The component can include a composite multi-layer reflective coating to form a mirror. A protective back-coat layer is deposited on a posterior surface of the mirror. A multi-layer weather-resistant coating may optionally be applied to the anterior surface of the polymer-based mirror in order to increase the weatherability and durability of the mirror. The various layers coating the synthetic resin substrate have their moisture permeabilities selected so that substantially equal amounts of moisture permeate through to both the anterior and posterior side of the synthetic resin substrate. A sol-gel coating can be used to deposit the multi-layers in a single step by providing gradient zones of zirconia/silica while enabling a hydrophobic or a hydrophilic exterior surface.

1 - 26 . (canceled)  
   
   
       27 . A method of forming a coating on a plastic component comprising the steps of: 
 providing a synthetic resin substrate of a predetermined configuration;    preparing a liquid sol-gel having a predetermined precursor concentration of colloid particles;    applying the liquid sol-gel having a predetermined precursor concentration of colloid particles to the synthetic resin substrate until a predetermined thickness is provided;    permitting the colloid particles to migrate and orientate in the liquid sol-gel over a predetermined time period by a zeta potential to enable a subsequent formation of an abrasion resistant exterior coating and a tie-bond layer on the surface of the synthetic resin substrate having respective different concentrations of colloid particles; and    curing the liquid sol-gel to form a solid abrasion resistant exterior coating.    
   
   
       28 . The method of  claim 27  wherein the liquid sol-gel includes a polysiloxane carrier.  
   
   
       29 . The method of  claim 28  wherein the precursor includes metal oxide colloid particles that form a majority by weight concentration adjacent an exterior surface as a first layer.  
   
   
       30 . The method of  claim 29  wherein a second layer of metal oxide colloid particles form an approximately 10% concentration by weight adjacent the first layer.  
   
   
       31 . The method of  claim 30  wherein a third layer of metal oxide colloid particles form an approximately 15% concentration by weight between the second layer and the synthetic resin substrate.  
   
   
       32 . The method of  claim 31  wherein the metal oxide colloid particles are zirconia/silica.  
   
   
       33 . The method of  claim 31  wherein a cathodic chemabsorbed zirconia/silica layer is formed between the third layer and the synthetic resin substrate.  
   
   
       34 . The method of  claim 32  further including applying a predetermined pH liquid solution to the exterior coating to form one of a hydrophobic and a hydrophilic surface by causing the zirconia/silica colloid particles to be one of cathodic and anodic.  
   
   
       35 . The method of  claim 27  wherein in the step of preparing a liquid sol-gel, the following sub-steps are performed comprising: 
 mixing a partial hydrolysis of tetraethoxysilane with a solution including ZrO 2  percursor to consume all of the water to provide a ZrO 2  doped SiO 2  solution; and    dispersing the ZrO 2  doped SiO 2  solution in a polysiloxane liquid carrier.    
   
   
       36 . The method of  claim 27  wherein in the step of preparing a liquid sol-gel, the following sub-steps are performed comprising: 
 mixing a full hydrolysis of tetramethoxysilane oligomer in water with a solution including a ZrO 2  percursor in a polar solvent to provide an anatose-type ZrO 2 ; and    dispersing the anatase-type ZrO 2  solution in a polysiloxane liquid carrier.    
   
   
       37 . The method of  claim 27  wherein in the step of preparing a liquid sol-gel, the following sub-steps are performed comprising: 
 mixing sodium metasalicate with water at a balanced pH of 1;    adding zirconyl chloride while stirring;    emulsifying the mixture in ethanol;    adding hexamethylenetetramine and urea;    filter and wash with ethanol to form an anatase ZrO 2  sol-gel; and    dispersing the anatase ZrO 2  sol-gel in a polysiloxane liquid carrier.    
   
   
       38 . The method of  claim 27  further including the steps of applying a reflective layer to one side of the coated synthetic resin substrate; and 
 sealing the reflective layer.    
   
   
       39 . A method of forming a plastic component with a transparent abrasion resistant coating comprising the steps of: 
 providing a synthetic resin substrate of a pre-determined configuration;    preparing a liquid sol-gel having a predetermined precursor concentration of colloid particles;    applying a liquid sol-gel having a predetermined precursor concentration of colloid particles to the synthetic resin substrate until a pre-determined thickness is provided;    permitting the colloid particles to migrate and orientate in the liquid sol-gel by a zeta potential to enable a subsequent formation of an abrasion resistant coating layer having a majority by weight of colloid particles adjacent the exterior coating surface and a lesser weight of colloid particles adjacent the synthetic resin substrate; and    curing the liquid sol-gel to form a solid abrasion resistant coating.    
   
   
       40 . The method of  claim 39  wherein the liquid sol-gel includes a polysiloxane carrier.  
   
   
       41 . The method of  claim 39  wherein the precursor colloid particles forms an approximately 75% concentration by weight adjacent an exterior surface as a first layer.  
   
   
       42 . The method of  claim 41  wherein a second layer of colloid particles forms an approximately 10% concentration by weight adjacent the first layer.  
   
   
       43 . The method of  claim 42  wherein a third layer of colloid particles forms an approximately 15% concentration by weight between the second layer and the synthetic resin substrate.  
   
   
       44 . The method of  claim 43  wherein a cathodic chemabsorbed colloid particle layer is formed between the third layer and the synthetic resin substrate.  
   
   
       45 . The method of  claim 39  further including applying a predetermined pH liquid solution to the exterior coating to form one of a hydrophobic and a hydrophilic surface by causing the colloid particles to be one of cathodic and anodic.  
   
   
       46 . The method of  claim 45  further including applying an aqueous solution of approximately 20 percent by weight NaOH to the exterior coating to form a hydrophilic surface.  
   
   
       47 . The method of  claim 39  wherein the colloid particles include a metal oxide.  
   
   
       48 . The method of  claim 47  wherein in the step of preparing a liquid sol-gel, the following sub-steps are performed comprising: 
 mixing a partial hydrolysis of tetraethoxysilane with a solution including ZrO 2  percursor to consume all of the water to provide a ZrO 2  doped SiO 2  solution; and    dispersing the ZrO 2  doped SiO 2  solution in a polysiloxane liquid carrier.    
   
   
       49 . The method of  claim 47  wherein in the step of preparing a liquid sol-gel, the following sub-steps are performed comprising: 
 mixing a full hydrolysis of tetramethoxysilane oligomer in water with a solution including a ZrO 2  percursor in a polar solvent to provide an anatose-type ZrO 2  and dispersing the anatase-type ZrO 2  solution in a polysiloxane liquid carrier.    
   
   
       50 . The method of  claim 47  wherein in the step of preparing a liquid sol-gel, the following sub-steps are performed comprising: 
 mixing sodium metasalicate with water at a balanced pH of 1;    adding zirconyl chloride while stirring;    emulsifying the mixture in ethanol;    adding hexamethylenetetramine and urea;    filter and wash with ethanol to form an anatase ZrO 2  sol-gel; and    dispersing the anatase ZrO 2  sol-gel in a polysiloxane liquid carrier.