Topologically structured polymer coating

Abstract

Sub-micron-structured (nanostructured) polymer film or coatings are made by coating a substrate with a mixture of materials. One of the materials is removed using a selective solvent, leaving pores or other nanostructure. The substrate may be grooved, providing a competing nanostructure. The coating may act as an antireflective coating, optical retarder, optical diffuser, or orientation layer.

1 - 47 . (canceled)  
     
     
         48 . A method of creating a topologically structured polymer film or coating on a substrate with a free surface facing away from the substrate, comprising 
 mixing at least two materials, wherein at least one material is not cross-linkable and the other material is,    applying the mixture to a substrate by using a coating method,    cross-linking said cross-linkable material, and    removing a substantial portion of the non-crosslinked material,    wherein the cross-linkable material is maintained in an oriented state having a molecular alignment during crosslinking.    
     
     
         49 . A method according to  claim 48 , wherein the cross-linking of the other material is effected by exposing it to light, which is optionally polarized.  
     
     
         50 . A method according to  claim 48 , wherein the cross-linkable material comprises molecules of a rod-like shape.  
     
     
         51 . A method according to  claim 48 , wherein the cross-linkable material is liquid crystalline.  
     
     
         52 . A method according to  claim 48 , wherein the non-cross-linkable material is liquid crystalline.  
     
     
         53 . A method according to  claim 52 , wherein the non-cross-linkable material is nematic liquid crystalline.  
     
     
         54 . A method according to  claim 48 , wherein the non-cross-linkable material comprises a surfactant.  
     
     
         55 . A method according to  claim 48 , wherein the orientation is imposed by an underlying orientation layer.  
     
     
         56 . A method according to  claim 55 , wherein the underlying orientation layer is a photo-oriented layer.  
     
     
         57 . A method according to  claim 48 , wherein the substrate already has an aligned structure, and the film or coating is applied thereto with an orientation which may be at from 0° to 90° to that alignment, or wherein this angle is different in different parts of the film or coating, optionally pixelwise.  
     
     
         58 . A method according to  claim 48 , wherein the cross-linking and alignment are induced by linearly polarized UV light.  
     
     
         59 . A method according to  claim 48 , wherein the two materials are dissolved in respective solvents before mixing, the solvents being mutually miscible but each being a poor solvent for the other solute.  
     
     
         60 . A method according to  claim 48 , wherein the cross-linkable material is present in 1/10 to 30 parts by weight per part of non-cross-linkable material.  
     
     
         61 . A method according to  claim 60 , wherein the cross-linkable material is present in ¼ to 4 parts by weight per part of non-cross-linkable material.  
     
     
         62 . A method according to  claim 48 , wherein the removal of the substantial portion of said one of the materials is by using a solvent inactive towards the other material.  
     
     
         63 . A topologically structured polymer film or coating on a substrate with a free surface facing away from the substrate, obtained by: 
 mixing at least two materials, wherein at least one material is not cross-linkable and at least one other material is,    applying the mixture to the substrate by using a coating method,    cross-linking said cross-linkable material, and    removing a substantial portion of the non-crosslinked material,    wherein the cross-linkable material is maintained in an oriented state having a molecular alignment during crosslinking.    
     
     
         64 . A topologically structured polymer film or coating, comprising a material which has hollows, wherein the material is crosslinked and wherein the cross-linked material has orientation having molecular alignment.  
     
     
         65 . A film or coating according to  claim 64 , wherein the crosslinked material is a liquid crystal polymer.  
     
     
         66 . A film or coating according to  claim 64 , wherein the hollows have arisen from the presence of another material which was then removed.  
     
     
         67 . A film or coating according to  claim 64 , wherein the orientation of the cross-linked material is different in different parts of the film or coating.  
     
     
         68 . A film or coating according to  claim 63 , wherein the film or coating comprises hollows at least 99% of which are smaller than 1000 nm in at least one direction parallel to the film or coating plane.  
     
     
         69 . A film or coating according to  claim 63 , wherein the film or coating comprises hollows at least 99% of which are smaller than 500 nm in at least one direction parallel to the film or coating plane.  
     
     
         70 . A film or coating according to  claim 63 , wherein the film or coating comprises hollows at least 99% of which are smaller than 200 nm in at least one direction parallel to the film or coating plane.  
     
     
         71 . A film or coating according to  claim 68 , wherein the average distance between adjacent hollows is less than 500 nm.  
     
     
         72 . A film or coating according to  claim 68 , wherein the hollows are elongated.  
     
     
         73 . A film or coating according to  claim 68 , wherein the hollows are of continuously narrowing shape from top to bottom.  
     
     
         74 . A film or coating according to  claim 63 , wherein the film or coating is optically transparent.  
     
     
         75 . A film or coating according to  claim 74 , wherein the film or coating is optically birefringent.  
     
     
         76 . A film or coating according to  claim 75  wherein the film or coating is optically birefringent such that the effective optical anisotropy of the film or coating is larger than the anisotropy of the film or coating material used.  
     
     
         77 . A film or coating according to  claim 75 , wherein the film or coating is optically birefringent such that the effective no of the film or coating is lower than no of the film or coating material used.  
     
     
         78 . A film or coating according to  claim 63 , wherein the film or coating can act as an optical diffuser.  
     
     
         79 . A film or coating according to  claim 78 , wherein the film or coating can act as an anisotropic optical diffuser.  
     
     
         80 . A film or coating according to  claim 63 , wherein the film or coating can act as a polarizer.  
     
     
         81 . A film or coating according to  claim 63 , wherein the film or coating is over-coated with an additional layer.  
     
     
         82 . A film or coating according to  claim 78 , wherein the film or coating is at least partly covered by a reflective layer that can act as a diffusing reflector.  
     
     
         83 . A film or coating according to  claim 82 , wherein the reflective layer can act as an anisotropic diffusing reflector.  
     
     
         84 . A film or coating according to  claim 82 , wherein the reflective layer is metallic.  
     
     
         85 . A stack or multilayer comprising two or more films or coatings according to  claim 63 .  
     
     
         86 . A film or coating according to  claim 63 , or a stack or multilayer comprising two or more films or coatings according to  claim 63 , on a substrate, wherein the substrate is optically transparent.  
     
     
         87 . An optical component comprising a substrate bearing a transparent liquid crystal polymer layer, which has hollows within its thickness spaced on average less than 500 nm apart, 99% of said hollows being less than 500 nm across and being at least twice as long as they are across, which liquid crystal polymer layer is aligned at a molecular level at 0° to 90° to an alignment of the hollows.  
     
     
         88 . An assembly comprising a layer of alignable molecules in contact with a film or coating according to  claim 63 , the molecules being aligned thereby.  
     
     
         89 . An antireflectively coated object comprising a film or coating according to  claim 63 .  
     
     
         90 . A liquid crystal cell wherein the liquid crystal molecules can adopt one of at least two different stable alignments in contact with a wall of the cell, the cell wall comprising a film or coating according to  claim 63 .  
     
     
         91 . An optical display device comprising a film or coating according to  claim 63  or a stack or multilayer comprising two or more films or coatings according to  claim 63 .  
     
     
         92 . An element for protection against forgery and/or copying, which comprises a film or coating according to  claim 63  or a stack or multilayer comprising two or more films or coatings according to  claim 63 .  
     
     
         93 . A method according to  claim 49 , wherein the light is UV light, which is optionally polarized.  
     
     
         94 . A method according to  claim 56 , wherein the underlying orientation layer is an azo dye or linearly polymerized photopolymer.  
     
     
         95 . An optical component according to  claim 87 , which is an optical retarder.  
     
     
         96 . An assembly comprising a layer of alignable molecules in contact with an optical component according to  claim 87 , the molecules being aligned thereby.  
     
     
         97 . An antireflectively coated object comprising an optical component according to  claim 87 .  
     
     
         98 . A liquid crystal cell wherein the liquid crystal molecules can adopt one of at least two different stable alignments in contact with a wall of the cell, the cell wall comprising an optical component according to  claim 87 .  
     
     
         99 . An optical display device comprising an optical component according to  claim 87 .  
     
     
         100 . A film or coating according to  claim 64 , wherein the film or coating comprises hollows at least 99% of which are smaller than 1000 nm in at least one direction parallel to the film or coating plane.  
     
     
         101 . A film or coating according to  claim 64 , wherein the film or coating comprises hollows at least 99% of which are smaller than 500 nm in at least one direction parallel to the film or coating plane.  
     
     
         102 . A film or coating according to  claim 64 , wherein the film or coating comprises hollows at least 99% of which are smaller than 200 nm in at least one direction parallel to the film or coating plane.  
     
     
         103 . A film or coating according to  claim 64 , wherein the film or coating comprises hollows and the average distance between adjacent hollows is less than 500 nm.  
     
     
         104 . A film or coating according to  claim 64 , wherein the film or coating comprises hollows and the hollows are elongated.  
     
     
         105 . A film or coating according to  claim 64 , wherein the film or coating comprises hollows and the hollows are of continuously narrowing shape from top to bottom.  
     
     
         106 . A film or coating according to  claim 64 , wherein the film or coating is optically transparent.  
     
     
         107 . A film or coating according to  claim 106 , wherein the film or coating is optically birefringent.  
     
     
         108 . A film or coating according to  claim 107 , wherein the film or coating is optically birefringent such that the effective optical anisotropy of the film or coating is larger than the anisotropy of the film or coating material used.  
     
     
         109 . A film or coating according to  claim 107 , wherein the film or coating is optically birefringent such that the effective no of the film or coating is lower than no of the film or coating material used.  
     
     
         110 . A film or coating according to  claim 64 , wherein the film or coating can act as an optical diffuser.  
     
     
         111 . A film or coating according to  claim 110 , wherein the film or coating can act as an anisotropic optical diffuser.  
     
     
         112 . A film or coating according to  claim 64 , wherein the film or coating can act as a polarizer.  
     
     
         113 . A film or coating according to  claim 64 , wherein the film or coating is over-coated with an additional layer.  
     
     
         114 . A film or coating according to  claim 110 , wherein the film or coating is at least partly covered by a reflective layer that can act as a diffusing reflector.  
     
     
         115 . A film or coating according to  claim 114 , wherein the reflective layer can act as an anisotropic diffusing reflector.  
     
     
         116 . A film or coating according to  claim 114 , wherein the reflective layer is metallic.  
     
     
         117 . A stack or multilayer comprising two or more films or coatings according to  claim 64 .  
     
     
         118 . A film or coating according to  claim 64 , or a stack or multilayer comprising two or more films or coatings according to  claim 64 , on a substrate, wherein the substrate is optically transparent.  
     
     
         119 . An assembly comprising a layer of alignable molecules in contact with a film or coating according to  claim 64 , the molecules being aligned thereby.  
     
     
         120 . An antireflectively coated object comprising a film or coating according to  claim 64 .  
     
     
         121 . A liquid crystal cell wherein the liquid crystal molecules can adopt one of at least two different stable alignments in contact with a wall of the cell, the cell wall comprising a film or coating according to  claim 64 .  
     
     
         122 . An optical display device comprising a film or coating according to  claim 64  or a stack or multilayer comprising two or more films or coatings according to  claim 64 .  
     
     
         123 . An element for protection against forgery and/or copying, which comprises a film or coating according to  claim 64  or a stack or multilayer comprising two or more films or coatings according to  claim 64.