Patent Publication Number: US-2021162708-A1

Title: Anti-fog mirror apparatus

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 15/522,912, filed Apr. 28, 2017, which is a U.S. national stage application under 35 U.S.C. § 371 of PCT Application No. PCT/US15/58582, filed Nov. 2, 2015, which is a continuation-in-part of U.S. patent application Ser. No. 14/530,420, (now U.S. Pat. No. 9,409,380) filed on Oct. 31, 2014. The disclosures of the above applications are incorporated herein by reference. 
    
    
     FIELD OF THE DISCLOSURE 
     The present disclosure relates to aesthetically pleasing reflective surface coverings having anti-fog properties. 
     BACKGROUND 
     Compositions and coatings which provide anti-fog and scratch resistant surfaces are known. However, when these compositions and coatings are applied to a surface, they can adversely impact the aesthetics and/or functionality of the surface to which they are applied. For example, the application of certain anti-fog compositions and coatings result in surfaces with imperfections and/or discoloration, Surface imperfections and discoloration may not be an issue for some surfaces, e.g., containers or refrigerator doors; however, surface coverings that require a certain level of reflectivity have little tolerance for surface imperfections or discoloration. Thus, there remains a need for reflective surface coverings which avoid discoloration and surface imperfections. Embodiments of the present invention are designed to meet these needs. 
     SUMMARY 
     In some embodiments, the present invention provides a mirror apparatus comprising: a reflective substrate; and an anti-fog complex coupled to the reflective substrate, the anti-fog complex comprising: a thermally activated adhesive layer atop the reflective substrate; a first polymeric layer atop the thermally activated adhesive layer; and a second polymeric layer atop the first polymeric layer; wherein the thickness ratio between the thermally activated adhesive layer and the first thermoplastic polymeric layer is from about 1.25:1 to about 2.75:1. 
     Other embodiments of the present invention provide a mirror apparatus comprising: a reflective substrate; and an anti-fog complex comprising: a pressure sensitive adhesive layer atop the substrate; a first polymeric layer comprising a thermoplastic polymer, the first polymeric layer atop the pressure sensitive adhesive layer; and a second polymeric layer atop the first polymeric layer; wherein the thickness ratio between the pressure sensitive adhesive layer and the first polymeric layer ranges from about 0.25:1 to about 1.25:1. 
     Further embodiments provide a method of preparing a mirror apparatus comprising: a) providing a reflective substrate; b) providing a multi-layer film comprising: a protective layer; and an anti-fog complex comprising: a first polymeric layer; an adhesive layer; and a second thermoplastic polymeric layer; c) laminating the multi-layer film and the reflective substrate together to form a laminated composite; d) maintaining the laminated composite in an ambient environment for a time sufficient to permit solidification of the multi-layer film; e) removing the protective layer from the laminated composite to expose the anti-fog complex; and f) performing a post-lamination cleaning phase. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will become more fully understood from the detailed description and the accompanying drawings, wherein: 
         FIG. 1  is a front perspective view of a mirror apparatus  1  comprising a mirror according to the present invention; 
         FIG. 1A  is a cross-sectional view of a portion of the mirror according to the present invention, the portion being identified by the dotted lines in  FIG. 1  and the cross-sectional view is taken alone the II line set forth in  FIG. 1 - FIG. 1A  is not drawn to scale; 
         FIG. 2  is a cross-sectional view of a portion of the mirror according to embodiments of the present invention, the portion being identified by the dotted lines in  FIG. 1  and the cross-sectional view is taken alone the II line set forth in  FIG. 1 - FIG. 2  is not drawn to scale; 
         FIG. 3  is a side view of an multi-layered film according to the present invention— FIG. 3  is not drawn to scale; and 
         FIG. 4  is a cross-sectional view of a portion of the mirror according to other embodiments of the present invention, the portion being identified by the dotted lines in  FIG. 1  and the cross-sectional view is taken alone the II line set forth in  FIG. 1 - FIG. 4  is not drawn to scale. 
     
    
    
     DETAILED DESCRIPTION 
     As used herein, the term “complex” refers to a plurality of components that are connected. According to the present invention, the terms “substantially” and “about” refers to +/−5% of the referenced value. According to the present invention, the term “substantially free” refers to less than 0.05 wt. % based on total weight of the referenced composition. 
     Referring to  FIGS. 1 and 1A  concurrently, a mirror apparatus  1  according to the present invention is disclosed. The mirror apparatus  1  generally comprises an annular frame  30  defining a central opening  40  and a mirror  80 . The mirror  80  is supported within the annular frame  30  and is a laminate structure that generally comprises a first major surface  82  opposite a second major surface  83 , the laminate structure comprising a reflective substrate  100  and an anti-fog complex  300 . 
     The reflective substrate  100  may comprise an upper surface  102  opposite a lower surface  103 . The reflective substrate  100  may have a thickness t 1  as measured from the upper surface  102  to the lower surface  103  of the reflective substrate  100 . The reflective substrate  100  may have a thickness t 1  ranging from about 2 mm to about 6 mm—including all values and sub-ranges there-between. The reflective substrate  100  may have a thickness t 1  ranging from about 2.5 mm to about 3.5 mm—including all values and sub-ranges there-between. The reflective substrate  100  may have a thickness t 1  ranging from about 2.75 mm to about 3.25 mm—including all values and sub-ranges there-between. In some embodiments, the reflective substrate  100  may have a thickness t 1  of about 3 mm. 
     The reflective substrate  100  may further comprise a transparent base layer  110  having an upper surface  112  opposite a lower surface  113  and a back coating  120  having an upper surface  122  opposite a lower surface  123 . The upper surface  102  of the reflective substrate  100  may comprise the upper surface  112  of the transparent base layer  110  and the lower surface  103  of the reflective substrate  100  may comprise the lower surface  123  of the back coating  120 . The upper surface  122  of the reflective back coating  120  may directly contact the lower surface  113  of the transparent base layer  110 . 
     The back coating  120  may comprise a reflective material. The transparent base layer  110  may be substantially clear and made of glass or a plastic material. For the purposes of this application, the phrases “substantially clear” or “optically clear” refers to materials having an optical transmission of at least about 90%, or even higher, and a haze value of below about 5%, or even lower. The transparent base layer  110  should be substantially clear such that the underlying back coating  120  forms a reflective surface on the lower surface  113  of the transparent base layer  110  when viewed in a direction extending from at least the upper surface  112  towards the lower surface  113  of the reflective substrate  100 . The transparent base layer  110  should be substantially clear such that the underlying back coating  120  forms a reflective surface when viewed from the first major surface  82  of the mirror  80 . Stated otherwise, a viewer should see their reflection in the reflective surface when viewing the mirror  80  in the direction of the upper surface  102  towards the lower surface  103  of the reflective substrate  100 . 
     The anti-fog complex  300  of the present invention is optically clear and comprises an upper surface  302  opposite a lower surface  303 . The anti-fog complex  300  may have a thickness t 2  as measured from the upper surface  302  to the lower surface  303  of the anti-fog complex  300 . The anti-fog complex  300  may comprise an adhesive layer  220 , a first polymeric layer  240 , and a second polymeric layer  260 . The second polymeric layer  260  may be atop the first polymeric layer  240 . The first polymeric layer  240  may be atop the adhesive layer  220 . The adhesive layer  200  may be atop the reflective substrate  100 . 
     The adhesive layer  220  may comprise an upper surface  222  opposite a lower surface  223 . The adhesive layer  220  may have a thickness t 3  as measured from the upper surface  222  to the lower surface  223  of the adhesive layer  223 . The lower surface  303  of the anti-fog complex  300  may comprise the lower surface  223  of the adhesive layer  220 . The adhesive layer  220  is optically clear. 
     The first polymeric layer  240  may comprise an upper surface  242  opposite a lower surface  243 . The first polymeric layer  240  may have a thickness t 4  as measured from the upper surface  242  to the lower surface  243  of the polymeric layer  240 . The first polymeric layer  240  is optically clear. 
     The first polymeric layer  240  may comprises a polymer selected from: polymethyl methacrylate; a polyamide; polybenzamidazole; polyethylene; polypropylene; polystyrene; polyvinyl chloride; polyethylene terephthalate; and polytetrafluoroethylene. In some embodiments, the polymer of the first polymeric layer  240  is a thermoplastic polymer. The first polymeric layer  240  may be formed from a thermoplastic polymer of polyethylene terephthalate. The first polymeric layer  240  may be substantially free of UV additives. In some embodiments, the first polymeric layer  240  may be completely free of UV additives. 
     The second polymeric layer  260  may comprise an upper surface  262  opposite a lower surface  263 . The second polymeric layer  260  may have a thickness t 5  as measured from the upper surface  262  to the lower surface  263  of the second polymeric layer  260 . The thickness t 5  of the second polymeric layer  260  may range from about 5 μm to about μm—including all values and sub-ranges there-between. The thickness t 5  of the second polymeric layer  260  may be about 10 μm. The upper surface  302  of the anti-fog complex  300  may comprise the upper surface  222  of the second polymeric layer  260 . 
     The second polymeric layer  260  comprises polyurethane. The polyurethane of the second polymeric layer may be hydrophilic. The polyurethane based layer may be formed from a resin composition comprising an isocyanate prepolymer having free isocyanate groups, and an organic solvent solution of a hydrophilic polyol and a surfactant having isocyanate-reactive functionality. In some embodiments, the hydrophilic polyol and the surfactant react with the free isocyanate groups in the isocyanate prepolymer to form the polyurethane backbone having both the hydrophilic moiety and the surfactant moiety chemically reacted therein and attached thereto. Suitable polyurethane based layers are described, for example, in U.S. Pat. No. 5,877,254. 
     In some embodiments, the surfactant has distinct hydrophilic and hydrophobic regions such that the desired interfacial tension between the surface and the condensing moisture is effectively reduced. 
     Cationic and anionic surfactants are preferred; however, non-ionic surfactants may also be useful, provided they are equipped with the reactive group functionality and exhibit the distinct hydrophilic and hydrophobic regions. In certain applications where non-ionic surfactants are used, they may be selected from ethoxylated or propoxylated alcohols, phenols, amides and amines. Non-ionic surfactants, however, are known to typically include isocyanate reactive groups such as hydroxyl groups. 
     Anionic and cationic surfactants rarely contain free, reactive groups. In some embodiments, wherein anionic and cationic surfactants are properly modified to include free reactive hydroxyl groups, or other groups which are reactive with isocyanate groups, such modifications will provide the necessary reaction site to incorporate into the polyurethane structure. 
     Ionic surfactants are preferred because they are often more effective wetting agents than non-ionic surfactants due to their ionic character. In the present invention, the surfactant anionics are free to migrate throughout the polymer complex since they are, bound to the reacted cations by electrostatic interaction rather than covalent bonding. 
     The isocyanate-reactive surfactant may be selected from an anionic surfactant, a cationic surfactant, and a mixture thereof. Although hydroxyl-bearing surfactants are preferred, a number of other reactive groups on the surfactant are contemplated, including amino, carboxyl and thiol groups. The surfactant may bear more than one or one-type of isocyanate-reactive group. The ionic surfactants are preferably quaternary cationic surfactants or anionic surfactants having hydroxyl groups in the cation portion. More preferably, the surfactant is a non-ethoxylated hydrocarbon chain with greater than 16 carbon atoms. A non-limiting list of examples of suitable anionic surfactants includes monoethanolamine salts of sulfonic acids, diethanolamine salts of sulfonic acids, triethanolamine salts of sulfonic acids and mixtures thereof. 
     Typically, anionic surfactants rarely contain free, reactive hydroxyl groups in their structure. As such, these substances must be prepared to incorporate free hydroxyl or other isocyanate-reactive groups. Hydroxylation is accomplished by neutralizing a hydroxyl bearing quaternary ammonium base such a choline hydroxide with an acid such as dodecylbenzene sulfonic acid, as further described herein in the examples. Other hydroxyl-bearing ammonium compounds include but are not limited to triethylethanol-, diethyldiethano-, and ethyltriethanolammonium salts. A non-limiting list of suitable sulfonic acids from which the salts are prepared includes dodecylbenzene sulfonic acid, napthalene sulfonic acid, lignin sulfonic acids, petroleum sulfonic acids and paraffin sulfonic acids. 
     Examples of hydroxyl-containing cationic-surfactants include, without limitation, ricinoleamidopropyl dimethylethylammonium ethosulfate, stearamidopropyl dimethylethanolammonium methasulfate and octadecylmethol diethanolammonium chloride. 
     The polyol that may be suitable for use in the present invention are of a hydrophilic character, and are capable of reacting with an isocyanate prepolymer to form a polyurethane chain. Non-limiting examples of suitable polyol for use in the present invention includes polyethylene glycol and ethylene glycol/propylene glycol copolymers and mixtures thereof. Other suitable hydrophilic polyol include polybutylene glycol, polyetheylene imine, amine-terminated polyethers and certain polyester polyol. 
     The isocyanate prepolymers contemplated for use with the present invention include those isocyanates containing reactive isocyanate groups and which are capable of forming polyurethane polymer chains as is well known to those skilled in the art. In preferred embodiments, the isocyanate prepolymer is a biuret or an isocyanurate of a diisocyanate. Most preferably, the diisocyanate is hexamethylene diisocyanate. Other useful diisocyanates include prepolymers of diisophorone diisocyanate, diphenylmethane diisocyanate, bis(methylcyclohexyl) diisocyanate and toluenediisocyanate. Blocking of the isocyanate group, for example with an oxime or phenol, and later removal of the protective group prior to reaction is also contemplated. When blocked isocyanates are employed, it is possible to use solvents or other compounds which, but for the protective group in the isocyanate, would react with and consume the isocyanate groups. 
     The second polymeric layer  260  may be substantially free of UV additives. In other embodiments, the second polymeric layer  260  is completely free of UV additives. 
     The anti-fog complex  300  of the present invention may have a thickness t 2  that is calculated as follows: 
     
       
      
       t 
       2 
       =t 
       3 
       +t 
       4 
       +t 
       5  
      
     
     The anti-fog complex  300  may be formed by the upper surface  222  of the adhesive layer  220  contacting the lower surface  243  of the first polymeric layer  240  and the upper surface  242  of the first polymeric layer  240  contacting the lower surface  263  of the second polymeric layer  260 . 
     The mirror  80  may be formed by the lower surface  263  of the second polymeric layer  260  contacting the upper surface  242  of the first polymeric layer  240 , the lower surface  243  of the second polymeric layer  240  contacting the upper surface  222  of the adhesive layer  220 , the lower surface  223  of the adhesive layer  220  contacting the upper surface  112  of the transparent base layer  110 , and the lower surface  113  of the transparent base layer  110  contacts the upper surface  122  of the back coating  120 . 
     The mirror  80  of the present invention may have a thickness to that is calculated as follows: 
     
       
      
       t 
       0 
       =t 
       1 
       +t 
       3 
       +t 
       4 
       +t 
       5  
      
     
     The mirror  80  of the present invention may comprise the lower surface  303  of the anti-fog complex  300  contacting the upper surface  102  of the reflective substrate  100 —wherein the lower surface  303  of the anti-fog complex  300  comprises the lower surface  223  of the adhesive layer  200 —such that the lower surface  303  of the anti-fog complex  300  is adhesively bonded (by the adhesive layer  220 ) to the upper surface  102  of the reflective substrate  100 . 
     Referring now specifically to the embodiments exemplified in  FIG. 2 , a mirror apparatus  1  comprising a mirror  80   a  will be described. The mirror  80   a  is similar to the mirror  80  except for the differences described herein below. The features of the mirror  80   a  that are described above with regard to the mirror  80  will not be repeated herein in the interest of brevity, it being understood that the description above with regard to the mirror  80  applies. Furthermore, features of the mirror  80   a  will be similarly numbered as similar features on the mirror  80  except that the a suffix of “a” will be used. For features of the mirror  80   a  that are numbered but not described, it should be understood that the description of the similar feature in the mirror  80  applies. 
     The present invention is directed to a mirror apparatus comprising a mirror  80   a  having an anti-fog complex  300   a  comprising an adhesive layer  220   a , a first polymeric layer  240   a , and a second polymeric layer  260   a , wherein the adhesive layer  220   a  is formed from a thermally activated adhesive composition. 
     The anti-fog complex  300   a  may have a thickness t 2a  ranging from about 250 μm to about 300 μm. In some embodiments, the anti-fog complex  300   a  has a thickness t 2a  ranging from about 255 μm to about 295 μm. In some embodiments, the anti-fog complex  300   a  has a thickness t 2a  ranging from about 260 μm to about 290 μm. In some embodiments, the anti-fog complex  300   a  has a thickness t 2a  ranging from about 265 μm to about 285 μm. In some embodiments, the anti-fog complex  300   a  has a thickness t 2a  ranging from about 270 μm to about 280 μm. In some embodiments, the anti-fog complex  300   a  has a thickness t 2a  of about 275 μm. 
     A ratio of adhesive layer  220   a  thickness t 3a  to the first polymeric layer  240   a  thickness t 4a  may range from about 1.25:1 to about 2.75:1—including all ratios and sub-ranges there-between. The ratio of adhesive layer  220   a  thickness t 3a  to the first polymeric layer  240   a  thickness t 4a  may range from about 1.25:1 to about 2.5:1—including all ratios and sub-ranges there-between. The ratio of adhesive layer  220   a  thickness t 3a  to the first polymeric layer  240   a  thickness t 4a  may range about 1.25:1 to about 2.25:1—including all ratios and sub-ranges there-between. The ratio of adhesive layer  220   a  thickness t 3a  to the first polymeric layer  240   a  thickness t 4a  may range from about 1.25:1 to about 2:1—including all ratios and sub-ranges there-between. The ratio of adhesive layer  220   a  thickness t 3a  to the first polymeric layer  240   a  thickness t 4a  may be about 1.5:1. 
     The adhesive layer  220   a  may be formed from a thermally activated adhesive composition and comprises an adhesive available from Akron Coating and Adhesives, Inc., e.g., ACA-40-004. Other suitable thermally activated adhesives are described in U.S. Pat. No. 6,753,379 to 3M Innovative Properties Company. In some embodiments, the thermally activated adhesive is in the form of a film. In some embodiments, the thermally activated adhesive is water-based. In some embodiments, the thermally activated adhesive is solvent-based. According to such embodiments, the adhesive layer  220   a  may be substantially free of UV additives. In other embodiments, the thermally activated adhesive layer may be completely free of UV additives. 
     The adhesive layer  220   a  formed from the thermally activated adhesive composition may have a thickness t 3a  ranging from about 140 μm to about 175 μm—including all values and sub-ranges there-between. 
     The first polymeric layer  240   a  may have a thickness t 3a  ranging from about 75 μm to about 125 μm—including all values and sub-ranges there-between. In some embodiments, the first polymeric layer  240   a  has a thickness t 3a  of from about 80 μm to about 120 μm—including all values and sub-ranges there-between. In some embodiments, the first polymeric layer  240   a  has a thickness t 3a  of from about 85 μm to about 115 μm—including all values and sub-ranges there-between. In some embodiments, the first polymeric layer  240   a  has a thickness t 3a  of from about 90 μm to about 110 μm—including all values and sub-ranges there-between. In some embodiments, the first polymeric layer  240   a  has a thickness t 3a  of from about 95 μm to about 105 μm—including all values and sub-ranges there-between. In some embodiments, the first polymeric layer  240   a  has a thickness t 3a  of about 100 μm. In some embodiments, the first polymeric layer  240   a  has a thickness t 3a  of about 101 μm. In some embodiments, the first polymeric layer  240   a  has a thickness t 3a  of about 102 μm. In some embodiments, the first polymeric layer  240   a  has a thickness t 3a  of 101.6 μm. 
     The adhesive layer  220   a  formed from the thermally activated adhesive composition may comprise from about 52 wt. % to about 65 wt. % of the anti-fog complex  300   a —including all values and sub-ranges there-between. The adhesive layer  220   a  formed from the thermally activated adhesive composition may comprise from about 55 wt. % to about 59 wt. % of the anti-fog complex  300   a —including all values and sub-ranges there-between. The adhesive layer  220   a  formed from the thermally activated adhesive composition may comprise about 57 wt. % of the anti-fog complex  300   a . The adhesive layer  220   a  According to the embodiments of may comprises 58 wt. % of the anti-fog complex  300   a.    
     The first polymeric layer  240   a  may comprise from about 28 wt. % to about 48 wt. % of the anti-fog complex  300   a —including all values and sub-ranges there-between. The first polymeric layer  240   a  may comprise from about 33 wt. % to about 43 wt. % of the anti-fog complex  300   a —including all values and sub-ranges there-between. The first polymeric layer  240   a  may comprise about 38 wt. % of the anti-fog complex  300   a.    
     The second polymeric layer  260   a  may comprise from about 1 wt. % to about 10 wt. % of the anti-fog complex  300   a —including all values and sub-ranges there-between. The second polymeric  260   a  layer may comprise from about 2 wt. % to about 7 wt. % of the anti-fog complex  300   a —including all values and sub-ranges there-between. The second polymeric layer  260   a  may comprise from about 3.5 wt. % to about 5.5 wt. % of the anti-fog complex  300   a —including all values and sub-ranges there-between. The second polymeric layer  260   a  may comprise about 4.5 wt. % of the anti-fog complex  300   a.    
     Referring now specifically to the embodiments exemplified in  FIG. 4 , a mirror apparatus  1  comprising a mirror  80   b  will be described. The mirror  80   b  is similar to the mirror  80  except for the differences described herein below. The features of the mirror  80   b  that are described above with regard to the mirror  80  will not be repeated herein in the interest of brevity, it being understood that the description above with regard to the mirror  80  applies. Furthermore, features of the mirror  80   b  will be similarly numbered as similar features on the mirror  80  except that the a suffix of “b” will be used. For features of the mirror  80   b  that are numbered but not described, it should be understood that the description of the similar feature in the mirror  80  applies. 
     The present invention is directed to a mirror apparatus comprising a mirror  80   b  having an anti-fog complex  300   b  comprising an adhesive layer  220   b , a first polymeric layer  240   b , and a second polymeric layer  260   b , wherein the adhesive layer  220   b  is formed a pressure sensitive adhesive composition. 
     The anti-fog complex  300   b  may have a thickness t 2b  ranging from about 50 μm to about 125 μm—including all values and sub-ranges there-between. In some embodiments, anti-fog complex  300   b  has a thickness t 2b  ranging from about 65 μm to about 110 μm—including all values and sub-ranges there-between. In some embodiments, anti-fog complex  300   b  has a thickness t 2a  ranging from about 75 μm to about 95 μm—including all values and sub-ranges there-between. In some embodiments, the anti-fog complex  300   b  has a thickness t 2b  ranging from about 80 μm to about 90 μm—including all values and sub-ranges there-between. In some embodiments, the anti-fog complex  300   b  has a thickness t 2b  of about 86 μm. 
     A ratio of adhesive layer  220   b  thickness t 3b  to the first polymeric layer  240   b  thickness t 4b  may range from about 0.2:1 to about 1.25:1—including all ratios and sub-ranges there-between. The ratio of adhesive layer  220   b  thickness t 3b  to the first polymeric layer  240   b  thickness t 4b  may range from about 0.25:1 to about 1:1—including all ratios and sub-ranges there-between. The ratio of adhesive layer  220   b  thickness t 3b  to the first polymeric layer  240   b  thickness t 4b  my range from about 0.5:1 to about 1:1—including all ratios and sub-ranges there-between. The ratio of adhesive layer  220   b  thickness t 3b  to the first polymeric layer  240   b  thickness t 4b  may range from about 0.65:1 to about 1:1—including all ratios and sub-ranges there-between. The ratio of adhesive layer  220   b  thickness t 3b  to the first polymeric layer  240   b  thickness t 4b  may be about 0.5:1. 
     According such embodiments, the adhesive layer  220   b  is formed from a pressure sensitive adhesive composition. The pressure sensitive composition is optically clear. The pressure sensitive adhesive composition may comprise one or more acrylic polymers, vinyl polymers, mixtures, or copolymers thereof. Non-limiting examples of acrylic polymer may include homopolymers or co-polymers of one or more acrylate monomer such as C1 to C10 esters of acrylic acid. Non-limiting examples acrylate monomer may include such as butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, ethyl (meth)acrylate, methyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, t-butyl (meth)acrylate, pentyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, isononyl (meth)acrylate and 2-ethylbutyl (meth)acrylate. In some embodiments, acrylic polymer may be a copolymer of an acrylate monomer and other monomers, such as ethylene. 
     In some embodiments, the pressure sensitive adhesive composition is in the form of a film. The adhesive layer  220   b  may be substantially free of UV additives. In other embodiments, the adhesive layer  220   b  may be completely free of UV additives. 
     The adhesive layer  220   b  may be formed from a pressure sensitive adhesive composition and have a thickness t 3b  ranging from about 10 μm to about 40 μm—including all values and sub-ranges there-between. The adhesive layer  220   b  may be formed from a pressure sensitive adhesive composition and have a thickness t 3b  ranging from about 20 μm to about 30 μm—including all values and sub-ranges there-between. The adhesive layer  220   b  may be formed from a pressure sensitive adhesive composition and have a thickness t 3b  of about 25 μm. 
     The first polymeric layer  240   b  may have a thickness t 3b  ranging from about 35 μm to about 90 μm—including all values and sub-ranges there-between. The first polymeric layer  240   b  may have a thickness t 3b  of from about 20 μm to about 75 μm—including all values and sub-ranges there-between. The first polymeric layer  240   b  may have a thickness t 3b  of from about 25 μm to about 65 μm—including all values and sub-ranges there-between. The first polymeric layer  240   b  may have a thickness t 3b  of from about 35 μm to about 60 μm—including all values and sub-ranges there-between. The first polymeric layer  240   b  may have a thickness t 3b  of from about 45 μm to about 55 μm—including all values and sub-ranges there-between. The first polymeric layer  240   b  may have a thickness t 3b  of about 50 μm. The first polymeric layer  240   b  may have a thickness t 3b  of about 51 μm. The first polymeric layer  240   b  may have a thickness t 3b  of about 50.8 μm. 
     The adhesive layer  220   b  may comprise from about 20 wt. % to about 40 wt. % of the anti-fog complex  300   b —including all values and sub-ranges there-between. The adhesive layer  220   b  may comprise from about 25 wt. % to about 35 wt. % of the anti-fog complex  300   b —including all values and sub-ranges there-between. The adhesive layer  220   b  may comprise about 29 wt. % of the anti-fog complex  300   b . According to the embodiments of  FIG. 3 , the adhesive layer  220   b  may comprises 30 wt. % of the anti-fog complex  300   b.    
     The first polymeric layer  240   b  may comprise from about 50 wt. % to about 70 wt. % of the anti-fog complex  300   b —including all values and sub-ranges there-between. The first polymeric layer  240   b  may comprise from about 55 wt. % to about 65 wt. % of the anti-fog complex  300   b —including all values and sub-ranges there-between. The first polymeric layer  240   b  may comprise about 57 wt. % to about 59 wt. % of the anti-fog complex  300   b . The first polymeric layer  240   b  may comprise about 58 wt. % of the anti-fog complex  300   b.    
     The second polymeric layer  260   b  may comprise from about 8 wt. % to about 16 wt. % of the anti-fog complex  300   b —including all values and sub-ranges there-between. The second polymeric  260   b  layer may comprise from about 10 wt. % to about 14 wt. % of the anti-fog complex  300   b —including all values and sub-ranges there-between. The second polymeric layer  260   b  may comprise about 12 wt. % to about 13 wt. % of the anti-fog complex  300   b.    
     Referring now to  FIG. 3 , the present invention may be a multi-layer film  200   b  having an upper surface  202   b  opposite a lower surface  203   b . The multi-layer film  200   b  may comprise a top protective layer  280   b , the anti-fog complex  300   b , and, optionally, a bottom protective layer  290   b , wherein the anti-fog complex  300   b  includes the adhesive layer  220   b  formed from the pressure sensitive adhesive composition, as previously discussed. Specifically, the multi-layer film  200   b  comprises a top protective layer  280   b  positioned atop the second polymeric layer  260   b , the second polymeric layer  260   b  being positioned atop the first polymeric layer  240   b , the first polymeric layer  240   b  being positioned atop the bottom protective layer  290   b.    
     The top protective layer  280   b  may comprise an upper surface  282   b  opposite a lower surface  283   b . The top protective layer  280   b  may have a thickness t 6b  as measured from the upper surface  282   b  to the lower surface  283   b  of the top protective layer  280   b . The thickness t 6b  of the top protective layer  280   b  may range from about 10 μm to about 38 μm—including all values and sub-ranges there-between. The top protective layer  280   b  may comprise a polymer such as polyethylene terephthalate. The upper surface  202   b  of the multi-layer film  200   b  may comprise the upper surface  282   b  of the top protective layer  280   b.    
     The bottom protective layer  290   b  may comprise an upper surface  292   b  opposite a lower surface  293   b . The bottom protective layer  290   b  may have a thickness t 9b  as measured from the upper surface  292   b  to the lower surface  293   b  of the bottom protective layer  290 . The thickness t 9b  of the bottom protective layer  290   b  may range from about 10 μm to about 38 μm—including all values and sub-ranges there-between. The bottom protective layer  290   b  may comprise a polymer such as polyethylene terephthalate. The lower surface  203   b  of the multi-layer film  200   b  may comprise the lower surface  293   b  of the bottom protective layer  290   b.    
     The anti-fog complex  300   b  may comprise about 60 to about 70 wt. % of the multi-layer film  200   b . The top protective layer  280   b  and the bottom protective layer  290   b  may each comprise about 15 wt. % to about 20 wt. % of the multi-layer film  200   b.    
     The multi-layer film  200   b  may have a thickness t 7b  that is calculated as follows: 
     
       
      
       t 
       7b 
       =t 
       3b 
       +t 
       4b 
       +t 
       5b 
       +t 
       6b 
       +t 
       9b  
      
     
     The multi-layer film  200   b  may have the following layer organization: the lower surface  283  of the top protective layer  280  may contact the upper surface  262  of the second polymeric layer  260 , the lower surface  263  of the second polymeric layer  260  may contact the upper surface  242  of the first polymeric layer  240 , the lower surface  243  of the first polymeric layer  240  may contact the upper surface  222  of the adhesive layer  220 , and the lower surface  223  of the adhesive layer  220  may contact the upper surface  292  of the bottom protective layer  290 . 
     During application, the bottom protective layer  290  may be removed, thereby exposing the lower surface  303  of the anti-fog complex  300 , which is then brought in contact with the upper surface  102  of a reflective substrate  100 . Specifically, removing the bottom protective layer  290  exposes the lower surface  223  of the adhesive layer  200 , which may then be contacted with the upper surface  102  of the reflective substrate  100  such that the lower surface  303  of the anti-fog complex  300  is adhesively bonded (by the adhesive layer  220 ) to the upper surface  102  of the reflective substrate  100 . Before or during application of the lower surface  303  of the anti-fog complex  300  onto the upper surface  102  of the reflective substrate  100 , the adhesive layer  220  may be heated (e.g., by heated roller) to a temperature ranging from about 48° C. to about 60° C. to help facilitate the application of the pressure sensitive adhesive composition of the adhesive layer  220  onto the reflective substrate  100 . Specifically, by using the addition of heat from the heated roller at a temperature ranging from about 48° C. to about 60° C., the resulting anti-fog complex  300   b  (which uses the pressure sensitive based adhesive layer  220 ) results in superior optical properties that include the anti-fog complex  300   b  being substantially clear (i.e., “optically clear”), thereby providing a superior mirror  80 . 
     After application, downward pressure may be applied to the upper surface  283  of the top protective layer  280 . The top protective layer  280  may then be removed, thereby exposing the top surface  302  of the anti-fog complex  300  and the top surface  262   b  of the second polymeric layer  260  to the surrounding environment. The exposed upper surface  302   b  of the anti-fog complex  300  may then be cleaned by a post-lamination cleaning cycle, described further herein. 
     Other embodiments provide a method of manufacturing a mirror including an adhesive layer formed from the thermally-activated adhesive composition comprising: a) providing a reflective substrate and a multi-layer film, the multi-layer film comprising a top protective layer atop an anti-fog complex, the anti-fog complex comprising: a first polymeric layer; an adhesive layer; a second polymeric layer; b) laminating the multi-layer film and the reflective substrate together to form a laminated composite; c) maintaining the laminated composite in ambient conditions for a time sufficient to permit solidification of the multi-layer film; d) removing the top protective layer from the laminated composite to expose the anti-fog complex; and e) performing a post-lamination cleaning cycle. 
     Referring now generally to the present invention, the post-lamination cleaning phase comprises a first cleaning step and a second cleaning step. In some embodiments, the second cleaning step is performed within 24 hours after completion of the first cleaning step. In some embodiments, the second cleaning step is performed at least 24 hours after the first cleaning step is completed. 
     In some embodiments, the second cleaning step is performed 30 minutes after completion of the first cleaning step. In some embodiments, the second cleaning step is performed one hour after completion of the first cleaning step. In some embodiments, the second cleaning step is performed two hours after completion of the first cleaning step. In some embodiments, the second cleaning step is performed four hours after completion of the first cleaning step. In some embodiments, the second cleaning step is performed 8 hours after completion of the first cleaning step. In some embodiments, the second cleaning step is performed twelve hours after completion of the first cleaning step. In some embodiments, the second cleaning step is performed eighteen hours after completion of the first cleaning step. 
     In some embodiments, the second cleaning step is performed from about 30 minutes to 24 hours after completion of the first cleaning step. In some embodiments, the second cleaning step is performed from about 1 hour to 18 hours after completion of the first cleaning step. In some embodiments, the second cleaning step is performed from about 2 hours to 12 hours after completion of the first cleaning step. In some embodiments, the second cleaning step is performed from about 4 hours to 10 hours after completion of the first cleaning step. In some embodiments, the second cleaning step is performed from about 6 hours to 8 hours after completion of the first cleaning step. 
     In some embodiments, exposure of the reflective surface covering to an environment having a relative humidity of greater than about 60% causes leaching or blooming of certain elements to the surface of the reflective surface covering, resulting in a white haze on that surface. Conventional methods of preparing reflective surface coverings have, heretofore, not been able to eliminate formation of this white haze. 
     In some embodiments, the anti-fog complex may be referred to as an anti-fog matrix. In those embodiments wherein the anti-fog complex is referred to as an anti-fog matrix, it is believed that one or more components of the anti-fog matrix releases one or more elements which present on the top surface of the reflective surface covering, under certain environmental conditions. In some embodiments, it is believed that these elements reach the top surface by permeating through the first polymeric layer. In other embodiments, it is believed that the presentation of these elements on the top surface is the result of a chemical reaction between an element of the second polymeric layer and an environmental constituent, which causes the element to emanate from the first polymeric layer. 
     In some embodiments, the first cleaning step comprises applying an alcohol based composition to the anti-fog complex. In some embodiments, the alcohol based composition is manually applied to the anti-fog complex. In some embodiments, the alcohol based composition is applied to the anti-fog complex using a roller. In some embodiments, the alcohol based composition is applied to the anti-fog complex using a paint roller. 
     In some embodiments, the first cleaning step further comprises removing the alcohol based composition from the anti-fog complex. In some embodiments, the first cleaning step further comprises removing the alcohol based composition from the anti-fog complex using a towel. In some embodiments, the towel comprises a natural fiber. In some embodiments, the towel is a cloth towel. 
     In some embodiments, the first cleaning step further comprises applying an alkaline solution to the anti-fog complex. In some embodiments, the alkaline solution is an ammonia based solution. In some embodiments, the alkaline solution is manually applied to the anti-fog complex. In some embodiments, the first cleaning step further comprises removing the alkaline solution from the anti-fog complex. In some embodiments, the alkaline solution is removed from the anti-fog complex using a cellulosic substrate. In some embodiments, the cellulosic substrate is a paper towel. 
     In some embodiments, the second cleaning step comprises applying an alcohol based composition to the anti-fog complex. In some embodiments, the second cleaning step further comprises removing the alcohol based composition from the anti-fog complex. In some embodiments, the second cleaning step further comprises removing the alcohol based composition from the anti-fog complex using a towel. In some embodiments, the towel comprises a natural fiber. In some embodiments, the towel is a cloth towel. 
     In some embodiments, the second cleaning step further comprises applying an alkaline solution to the anti-fog complex. In some embodiments, the alkaline solution is an ammonia based solution. In some embodiments, the alkaline solution is manually applied to the anti-fog complex. In some embodiments, the second cleaning step further comprises removing the alkaline solution from the anti-fog complex. In some embodiments, the alkaline solution is removed from the anti-fog complex using a cellulosic substrate. In some embodiments, the cellulosic substrate is a paper towel. 
     In some embodiments, the first cleaning step and/or the second cleaning step are automated. 
     In some embodiments, the step of laminating the multi-layer film and the reflective substrate together to form a laminated composite is performed in a cleanroom. As used herein, the term “clean room” is intended to refer to an environment having an ISO 14644-1 cleanroom standard of between ISO 1 and ISO 8. 
     In some embodiments, the laminated composite is maintained in an ambient environment for from about 48 to about 72 hours. In some embodiments, the laminated composite is maintained in an ambient environment for about 48 hours. In some embodiments, the laminated composite is maintained in an ambient environment for about 72 hours. In some embodiments, the laminated composite is maintained in an ambient environment for at least 84 hours. In some embodiments, the laminated composite is maintained in an ambient environment for at least 96 hours. 
     In some embodiments, the reflective substrate and the multi-layer film are laminated together using a hot roll laminator. In some embodiments, the reflective substrate and the multi-layer film are laminated together in a cleanroom. In some embodiments, the hot roll laminator has a run speed of between about 1 foot/minute and about 10 feet/minute. In some embodiments, the hot roll laminator has a run speed of between about 2 feet/minute and about 9 feet/minute. In some embodiments, the hot roll laminator has a run speed of between about 3 feet/minute and about 8 feet/minute. In some embodiments, the hot roll laminator has a run speed of between about 4 feet/minute and about 7 feet/minute. In some embodiments, the hot roll laminator has a run speed of between about 4 feet/minute and about 6 feet/minute. In other embodiments, the hot roll laminator has a run speed of about 3 feet/minute. In other embodiments, the hot roll laminator has a run speed of about 4 feet/minute. In other embodiments, the hot roll laminator has a run speed of about 5 feet/minute. 
     In some embodiments, the reflective substrate is inspected for defects prior to laminating the multi-layer film and the reflective substrate together. 
     In some embodiments, the multi-layer film and the reflective substrate are laminated together at a pressure of from about 10 pounds per square inch (psi) to about 40 psi. In some embodiments, the multi-layer film and the reflective substrate are laminated together at a pressure of from about 15 psi to about 35 psi. In some embodiments, the multi-layer film and the reflective substrate are laminated together at a pressure of from about 20 psi to about 30 psi. In some embodiments, the multi-layer film and the reflective substrate are laminated together at a pressure of about 25 psi. 
     In some embodiments, the multi-layer film is maintained at a tension of from about 15 pounds to about 30 pounds during the laminating step. In other embodiments, the multi-layer film is maintained at a tension of from about 20 pounds to about 25 pounds during the laminating step. 
     In some embodiments, the hot roll laminator is maintained at a temperature of from about 105° C. to about 130° C. during the laminating step. In some embodiments, the hot roll laminator is maintained at a temperature of from about 110° C. to about 125° C. during the laminating step. In some embodiments, the hot roll laminator is maintained at a temperature of from about 115° C. to about 120° C. during the laminating step. 
     Referring now generally to the present invention, the mirror  80  has a scratch/dig ratio between 120/80 and 10/5. In some embodiments, the mirror  80  has a scratch/dig ratio between 80/50 and 20/10. In some embodiments, the mirror  80  has a scratch/dig ratio between 60/40 and 40/20. The mirror  80  may have a Yellow Index Rating of greater than 3. In other embodiments, the mirror  80  of the present invention has a Yellow Index Rating of greater than or equal to 4. 
     In some embodiments, the reflective surface has a visible light reflectance of greater than 75%. In some embodiments, the reflective surface has a visible light reflectance of greater than 80%. In some embodiments, the reflective surface has a visible light reflectance of greater than 85%. In some embodiments, the reflective surface has a visible light reflectance of greater than 90%. In some embodiments, the reflective surface has a visible light reflectance of greater than 95%. In some embodiments, the reflective surface has a visible light reflectance of greater than 97.5%. In some embodiments, the reflective surface has a visible light reflectance of greater than 98%. In some embodiments, the reflective surface has a visible light reflectance of greater than 99%. 
     In some embodiments, each layer of the multi-layer film has a particular arrangement. In some embodiments, the first polymeric layer is positioned between the adhesive layer and the second polymeric layer. In those embodiments wherein the multi-layer film further comprises a protective layer, the protective layer is adjacent to the second polymeric layer. In some embodiments wherein the multi-layer film further comprises a protective layer, there are no intervening layers between the protective layer and the second polymeric layer. 
     In some embodiments, the second polymeric layer forms the top surface of the multi-layer film. In those embodiments wherein the multi-layer film comprises a protective layer, the protective layer forms the top surface of the multi-layer film. 
     In some embodiments, the first polymeric layer is positioned between the adhesive layer and the second polymeric layer, such that there are no intervening layers between the first polymeric layer and the adhesive layer. In some embodiments, the first polymeric layer is positioned between the adhesive layer and the second polymeric layer, such that there are no intervening layers between the first polymeric layer and the second polymeric layer. In some embodiments, the first polymeric layer is positioned between the adhesive layer and the second polymeric layer, such that there are no intervening layers between the first polymeric layer and the second polymeric layer or any intervening layers between the first polymeric layer and the adhesive layer. 
     In some embodiments, each layer of the anti-fog complex has a particular arrangement. In some embodiments, the first polymeric layer is positioned between the adhesive layer and the second polymeric layer of the anti-fog complex. In some embodiments, the second polymeric layer forms the top surface of the anti-fog complex. In some embodiments, the anti-fog complex does not contain any intervening layers between the first polymeric layer and the adhesive layer. In some embodiments, the anti-fog complex does not contain any intervening layers between the first polymeric layer and the second polymeric layer. In some embodiments, the anti-fog complex does not contain any intervening layers between the first polymeric layer and the second polymeric layer or any intervening layers between the first polymeric layer and the adhesive layer. 
     The invention will be described in greater detail by way of specific examples. The following examples are offered for illustrative purposes and are not intended to limit the invention in any manner. Those skilled in the art will readily recognize a variety of noncritical parameters, which can be changed or modified to yield essentially the same results. 
     EXAMPLES 
     Example 1 
     Table 1 (below) describes the results of evaluations performed on exemplary reflective surface coverings of the present invention and comparative surface coverings. All surface coverings are evaluated for discoloration, quality of lamination and functionality; and an aggregate pass/fail rating is assigned. A surface covering which does not meet the standard for discoloration, quality of lamination or functionality receives a “Fail” rating. 
     Discoloration (e.g., yellowing of the product) and quality of lamination are assessed by visual inspection; and functionality is assessed by visible light reflectance. 
     
       
         
           
               
               
               
               
             
               
                   
                 TABLE 1 
               
             
            
               
                   
                   
               
               
                   
                 Thickness 
                   
                   
               
               
                   
                 (μm) 
               
            
           
           
               
               
               
               
               
            
               
                 Example 
                 Adhesive 
                 PET 
                 Adhesive 
                 Pass/Fail 
               
               
                   
               
            
           
           
               
               
               
               
               
            
               
                 Ex. I 
                 152.4 
                 101.6 
                 A* 
                 Pass 
               
               
                 Ex. II 
                 152.4 
                 101.6 
                 A 
                 Pass 
               
               
                 Comp. Ex. I 
                 152.4 
                 50.8 
                 A 
                 Fail 
               
               
                 Comp. Ex. II 
                 152.4 
                 50.8 
                 B** 
                 Fail 
               
               
                 Comp. Ex. III 
                 152.4 
                 101.6 
                 B 
                 Fail 
               
               
                 Comp. Ex. IV 
                 177.8 
                 50.8 
                 A 
                 Fail 
               
               
                 Comp. Ex. V 
                 177.8 
                 101.6 
                 B 
                 Fail 
               
               
                 Comp. Ex. VI 
                 152.4 
                 50.8 
                 A 
                 Fail 
               
               
                 Comp. Ex. VII 
                 152.4 
                 50.8 
                 A 
                 Fail 
               
               
                 Comp. Ex. VIII 
                 152.4 
                 101.6 
                 C*** 
                 Fail 
               
               
                 Comp. Ex. IX 
                 88.9 
                 101.6 
                 B 
                 Fail 
               
               
                 Comp. Ex. X 
                 63.5 
                 101.6 
                 B 
                 Fail 
               
               
                 Comp. Ex. XI 
                 114.3 
                 101.6 
                 B 
                 Fail 
               
               
                 Comp. Ex. XII 
                 38.1 
                 101.6 
                 B 
                 Fail 
               
               
                   
               
               
                 *Thermally activated adhesive 
               
               
                 **Hot melt adhesive 
               
               
                 ***Adhesive + UV additive 
               
            
           
         
       
     
     The results described in Table 1 (above) demonstrate that exemplary reflective surface coverings of the present invention meet the quality standards for discoloration, quality of lamination and functionality, while the comparative reflective surface coverings fail to meet at least one of these quality standards. 
     Example 2 
     Reflective surface coverings prepared according to exemplary methods of the present invention and reflective surface coverings prepared in accordance with comparative methods are evaluated. The exemplary methods of the present invention included first and second cleaning steps, while the comparative methods did not. The surface coverings are visually inspected for the presence of white haze on the top surface. Remarkably, reflective surface coverings prepared by comparative methods possess a white haze on the top surface; whereas reflective surface coverings prepared in accordance with exemplary methods of the present invention are free of white haze. 
     It is intended that any patents, patent applications or printed publications, including books, mentioned in this patent document be hereby incorporated by reference in their entirety. 
     As those skilled in the art will appreciate, numerous changes and modifications may be made to the embodiments described herein, without departing from the spirit of the invention. It is intended that all such variations fall within the scope of the invention.