Dry adhesives and methods for making dry adhesives

Abstract

Dry adhesives and methods for forming dry adhesives. A method of forming a dry adhesive structure on a backing material, comprises: forming a template backing layer of energy sensitive material on the backing material; forming a template layer of energy sensitive material on the template backing layer; exposing the template layer to a predetermined pattern of energy; removing a portion of the template layer related to the predetermined pattern of energy, and leaving a template structure formed from energy sensitive material and connected to the substrate via the template backing layer.

1 . A method of forming a template structure, comprising the steps performed in the following sequence:
 forming a template backing layer of energy sensitive material on a backing material;   exposing the template backing layer to a predetermined pattern of energy from an energy source;   forming a template layer of energy sensitive material on the template backing layer;   applying a mask to the template layer;   exposing the template layer to an energy source; and   removing the mask and a portion of the template layer not exposed to the energy source to create a pattern of exposed energy sensitive material fiber arrays forming the template structure,   wherein the pattern of exposed energy sensitive material fiber arrays is selected from the group consisting of (i) polymer micro-scale fibers, (ii) polymer nano-scale fibers, and (iii) polymer micro- and nanoscale fibers.   
     
     
         2 . The method according to  claim 1 , wherein the step of exposing the template layer to the energy source further comprises directing the energy source at a perpendicular angle to a surface of the template backing, wherein tip surfaces of the exposed energy sensitive material fiber arrays are flat and substantially parallel with the surface of the template backing layer. 
     
     
         3 . The method according to  claim 1 , wherein the step of exposing the template layer to the energy source further comprises directing the energy source at a non-perpendicular angle to a surface of the template backing layer, wherein tip surfaces of the exposed energy sensitive material fiber arrays are flat and substantially parallel with the surface of the template backing layer. 
     
     
         4 . A method of forming a negative mold product having polymer micro- and/or nano-fiber arrays, comprising the steps performed in the following sequence:
 providing a template structure formed from energy sensitive material product having fiber arrays selected from the group consisting of (i) polymer micro-scale fibers, (ii) polymer nano-scale fibers, and (iii) polymer micro- and nanoscale fibers;   depositing a mold material into the template structure, wherein the mold material is different from a material of the template structure;   allowing the mold material to cure; and   separating the mold material from the template structure to form the negative mold product having polymer micro- and nano-fiber arrays.   
     
     
         5 . The method according to  claim 4 , wherein the fiber arrays of the template structure are oriented at a perpendicular angle to a surface of a template backing layer of the template structure, wherein tip surfaces of the fiber arrays are flat and substantially parallel with the surface of the template backing layer. 
     
     
         6 . The method according to  claim 4 , wherein the fiber arrays of the template structure are oriented at a non-perpendicular angle to a surface of a template backing layer of the template structure, wherein tip surfaces of the fiber arrays are flat and substantially parallel with the surface of the template backing layer. 
     
     
         7 . A method of forming a product having polymer micro- and/or nano-fiber arrays, comprising the step performed in the following sequence:
 providing a negative mold with negative shapes of polymer micro- and/or nano-fiber arrays;   depositing a dry adhesive material having one or more polymer micro- and/or nano-fibers into the negative mold;   allowing the dry adhesive material to cure; and   separating the dry adhesive material from the negative mold to form the product having polymer micro- and/or nano-fiber arrays.   
     
     
         8 . The method according to  claim 7 , wherein the step of depositing further comprises overfilling the negative mold to form an integral dry adhesive backing layer. 
     
     
         9 . The method according to  claim 7 , wherein the negative shapes of polymer micro- and/or nano-fiber arrays are oriented at a perpendicular angle to a surface of a template backing layer of the template structure. 
     
     
         10 . The method according to  claim 7 , wherein the negative shapes of polymer micro- and/or nano-fiber arrays are oriented at a non-perpendicular angle to a surface of a template backing layer of the template structure. 
     
     
         11 . The method according to  claim 8 , wherein tip surfaces of the polymer micro- and/or nano-fiber arrays of the product are flat and substantially parallel with a surface of the integral dry adhesive backing layer. 
     
     
         12 . A method of forming a product having hierarchical structures of polymer micro- and/or nano-fiber arrays, comprising the step performed in the following sequence:
 forming a first layer of energy sensitive material on a backing material to form a first wafer, wherein the energy sensitive material includes polymer micro- and/or nano-fibers;   baking the first wafer;   exposing the first layer to a predetermined pattern of energy from an energy source;   forming a second layer of energy sensitive material on to the first layer to form a second wafer, wherein the second layer is a first layer of fibers, wherein the energy sensitive material includes polymer micro- and/or nano-fibers;   baking the second wafer;   exposing the second layer to a first circular array pattern of energy from an energy source energy source to form base fibers;   baking the second wafer to cure the second layer;   forming a third layer of energy sensitive material on to the second layer to form a third wafer, wherein the third layer is a second layer of fibers;   heating the third layer;   exposing the third layer to a second circular array pattern of energy from the energy source to form a second layer of fibers, wherein the second layer of fibers being smaller than the base fibers; and   removing the first and second layers not exposed to the first and second circular array patterns of energy to form the product having hierarchical structures of polymer micro- and/or nano-fiber arrays.   
     
     
         13 . The method according to  claim 12 , wherein the step of exposing the first layer to an energy source further comprises directing the energy source at a perpendicular angle to a surface of the first wafer to form polymer micro- and/or nano-fiber arrays at the perpendicular angle to the surface of the first wafer. 
     
     
         14 . The method according to  claim 12 , wherein the step of exposing the first layer to an energy source further comprises directing the energy source at a non-perpendicular angle to a surface of the first wafer to form polymer micro- and/or nano-fiber arrays at the non-perpendicular angle to the surface of the first wafer. 
     
     
         15 . The method according to  claim 12 , wherein the step of exposing the second layer to an energy source further comprises directing the energy source at a perpendicular angle to a surface of the second wafer to form polymer micro- and/or nano-fiber arrays at the perpendicular angle to the surface of the second wafer. 
     
     
         16 . The method according to  claim 12 , wherein the step of exposing the second layer to an energy source further comprises directing the energy source at a non-perpendicular angle to a surface of the second wafer to form polymer micro- and/or nano-fiber arrays at the non-perpendicular angle to the surface of the second wafer. 
     
     
         17 . The method according to  claim 12 , wherein the step of exposing the third layer to an energy source further comprises directing the energy source at a perpendicular angle to a surface of the third wafer to form polymer micro- and/or nano-fiber arrays at the perpendicular angle to the surface of the third wafer. 
     
     
         18 . The method according to  claim 12 , wherein the step of exposing the third layer to an energy source further comprises directing the energy source at a non-perpendicular angle to a surface of the third wafer to form polymer micro- and/or nano-fiber arrays at the non-perpendicular angle to the surface of the third wafer. 
     
     
         19 . A product of the process according to  claim 1 . 
     
     
         20 . A product of the process according to  claim 4 . 
     
     
         21 . A product of the process according to  claim 7 . 
     
     
         22 . A product of the process according to  claim 12 . 
     
     
         23 . The method according to  claim 1 , wherein the energy sensitive material of the template backing layer is selected from the group consisting of photoresist material, anti-reflective material, and adhesive material. 
     
     
         24 . The method according to  claim 4 , wherein the energy sensitive material of the template structure is selected from the group consisting of photoresist material, anti-reflective material, and adhesive material. 
     
     
         25 . The method according to  claim 12 , wherein the energy sensitive material of the first layer is selected from the group consisting of photoresist material, anti-reflective material, and adhesive material. 
     
     
         26 . The method according to  claim 4 , wherein the step of providing a template structure formed from energy sensitive material product having fiber arrays selected from the group consisting of (i) polymer micro-scale fibers, (ii) polymer nano-scale fibers, and (iii) polymer micro- and nanoscale fibers further comprises the steps of:
 forming a template backing layer of energy sensitive material on a backing material;   exposing the template backing layer to a predetermined pattern of energy from an energy source;   forming a template layer of energy sensitive material on the template backing layer;   applying a mask to the template layer;   exposing the template layer to an energy source;   removing the mask and a portion of the template layer not exposed to the energy source to create a pattern of exposed energy sensitive material fiber arrays forming the template structure, wherein the pattern of exposed energy sensitive material fiber arrays is selected from the group consisting of (i) polymer micro-scale fibers, (ii) polymer nano-scale fibers, and (iii) polymer micro- and nanoscale fibers.   
     
     
         27 . A method of forming a negative mold product having polymer micro- and/or nano-fiber arrays, comprising the steps performed in the following sequence:
 forming a mold backing layer of energy sensitive material on a backing material;   exposing the mold backing layer to a predetermined pattern of energy from an energy source;   forming a mold layer of energy sensitive material on the mold backing layer;   applying a mask to the mold layer;   exposing the mold layer to an energy source; and   removing the mask and a portion of the mold layer not exposed to the energy source to create a pattern of exposed energy sensitive material fiber arrays forming the negative mold product, wherein the pattern of exposed energy sensitive material fiber arrays is selected from the group consisting of (i) polymer micro-scale fibers, (ii) polymer nano-scale fibers, and (iii) polymer micro- and nanoscale fibers.   
     
     
         28 . The method according to  claim 27 , wherein the fiber arrays of the negative mold product are oriented at a perpendicular angle to a surface of a template backing layer of the template structure, wherein tip surfaces of the fiber arrays are flat and substantially parallel with the surface of the template backing layer. 
     
     
         29 . The method according to  claim 27 , wherein the fiber arrays of the template structure are oriented at a non-perpendicular angle to a surface of a template backing layer of the template structure, wherein tip surfaces of the fiber arrays are flat and substantially parallel with the surface of the template backing layer. 
     
     
         30 . The method according to  claim 1 , wherein the backing material is a substrate. 
     
     
         31 . The method according to  claim 1 , wherein the backing material is a coating. 
     
     
         32 . The method according to  claim 12 , wherein the backing material is a substrate. 
     
     
         33 . The method according to  claim 12 , wherein the backing material is a coating. 
     
     
         34 . The method according to  claim 26 , wherein the backing material is a substrate. 
     
     
         35 . The method according to  claim 26 , wherein the backing material is a coating. 
     
     
         36 . The method according to  claim 27 , wherein the backing material is a substrate. 
     
     
         37 . The method according to  claim 27 , wherein the backing material is a coating. 
     
     
         38 . A method of manufacturing a product having polymer micro- and/or nano-fibers comprising the steps of:
 forming a dry adhesive backing layer of energy sensitive material on a backing material;   exposing the dry adhesive backing layer to a predetermined pattern of energy from an energy source;   forming a dry adhesive layer of energy sensitive material on the dry adhesive backing layer;   applying a mask to the dry adhesive layer;   exposing the dry adhesive layer to an energy source; and   removing the mask and a portion of the dry adhesive layer not exposed to the energy source to create a pattern of exposed energy sensitive material fiber arrays forming the product,   wherein the pattern of exposed energy sensitive material fiber arrays is selected from the group consisting of (i) polymer micro-scale fibers, (ii) polymer nano-scale fibers, and (iii) polymer micro- and nanoscale fibers.   
     
     
         39 . The method according to  claim 1 , wherein the template structure is a positive representation of a final product. 
     
     
         40 . The method according to  claim 4 , wherein the negative mold product is a negative representation of a final product. 
     
     
         41 . The method according to  claim 27 , wherein the negative mold product is a negative representation of a final product.