Super-hydrophobic fiber having needle-shaped nano structure on its surface, method for fabricating the same and fiber product comprising the same

Abstract

A super-hydrophobic fiber of the present disclosure includes: a nano-needle fiber having a surface including needle-shaped nano structures; and a coating layer disposed on the surface including the nano structures, and containing a hydrophobic material. The fiber has no aging effect, and thus, is excellent in durability, and has such a large contact angle and such as small sliding angle that the fiber may not be wet with water. A method for fabricating the super-hydrophobic fiber includes: a preparation step of preparing a pre-treating fiber; an etching step of etching a surface and an inner portion of the pre-treating fiber to fabricate a nano-needle fiber having a surface on which needle-shaped nano structures are formed; and a coating step of forming a coating layer containing a hydrophobic material, and enables mass production and is performed by simple processes. Further, an article including the super-hydrophobic fiber is an article in which no liquid drop is absorbed, scarcely adsorbs a contaminant, needs not be dried, and thus, may be widely applied even to recreational articles.

What is claimed is: 
     
         1 . A super-hydrophobic fiber comprising:
 a nano-needle fiber having a surface comprising needle-shaped nano structures; and   a coating layer disposed on the surface comprising needle-shaped nano structures;   wherein the needle shaped nano structure has a height of 50 to 150 nm and a width of 5 to 20 nm, and   the surface comprising needle-shaped nano structures comprises 2 million to 4 million needle-shaped nanostructures per 1 mm 2  of an area.   
     
     
         2 . The super-hydrophobic fiber of  claim 1 , wherein the needle-shaped nano structures are formed on the outermost surface of a pre-treating fiber and at the inner surface portion which is up to 100 μm deep from the outermost surface. 
     
     
         3 . The super-hydrophobic fiber of  claim 1 , wherein the super-hydrophobic fiber is one material selected from the group consisting of polyester, polyurethane, polyamide, polyvinyl alcohol, polyvinyl chloride, polyvinylidene chloride, acrylonitrile, polypropylene, polyacryl, and a combination thereof. 
     
     
         4 . The super-hydrophobic fiber of  claim 1 , wherein the coating layer has a thickness of 5 to 100 nm. 
     
     
         5 . The super-hydrophobic fiber of  claim 1 , wherein the hydrophobic material is one selected from the group consisting of hexamethyldisiloxane (HMDSO), molybdenum disulfide (MoS 2 ), boron nitride (BN), polytetra fluoroethylene (PTFE), fluorinated diamond like carbon (F-DLC), and a combination thereof. 
     
     
         6 . The super-hydrophobic fiber of  claim 1 , wherein the super-hydrophobic fiber has a contact angle of 150 degree or more with pure water. 
     
     
         7 . The super-hydrophobic fiber of  claim 1 , wherein the super-hydrophobic fiber has a sliding angle of 3 degree or less. 
     
     
         8 . A method for fabricating super-hydrophobic fiber, the method comprising:
 a preparation step of preparing a pre-treating fiber to be subjected to super-hydrophobic treatment;   an etching step of etching an outermost surface of the pre-treating fiber and an inner surface portion which is 100 μm deep from the outermost surface to fabricate a nano-needle fiber having a surface on which needle-shaped nano structures are formed; and   a coating step of forming a coating layer containing a hydrophobic material on the surface on which nano structures of the fiber are formed.   
     
     
         9 . The method of  claim 8 , wherein he etching step is one method selected from the group consisting of plasma etching, reactive ion etching, ion-milling, electro discharge machining (EDM), and a combination thereof. 
     
     
         10 . The method of  claim 9 , wherein the plasma etching is performed for 30 sec to 90 min while a reactive gas is included, and the reactive gas is one selected from the group consisting of CF 4 , CHF 3 , C 2 F 6 , C 2 Cl 2 F 4 , C 3 F 8 , C 4 F 8 , SF 6 , O 2 , and a mixture thereof. 
     
     
         11 . The method of  claim 10 , wherein the plasma etching is performed under conditions of a pressure of 10 to 100 mTorr, an rf-power of 100 to 400 W, and a bias voltage of 300 to 500 V for 5 min to 40 min. 
     
     
         12 . The method of  claim 8 , wherein in the coating step, a coating layer containing a hydrophobic material is formed by one selected from the group consisting of Plasma Enhanced Chemical Vapor Deposition (PECVD), Atmospheric Chemical Vapor Deposition (APCVD), Low Pressure Chemical Vapor Deposition (LPCVD), Metal-Organic Chemical Vapor Deposition (MOCVD), Ultra-high vacuum Chemical Vapor Deposition (UHCVD), Atomic Layer Deposition (ALD), and a combination thereof. 
     
     
         13 . The method of  claim 8 , wherein the coating step is performed by plasma enhanced chemical vapor deposition (PECVD), and is performed under conditions of a pressure of 5 to 30 mTorr, an rf-power of 150 to 400 W, and a bias voltage of 300 to 500 V. 
     
     
         14 . The method of  claim 8 , wherein the needle-shaped nano structure has a height of 50 to 150 nm and a width of 5 to 20 nm, and comprises 2 million to 4 million needles per 1 mm 2  of a surface area of the fiber. 
     
     
         15 . The method of  claim 8 , wherein the fiber is one selected from the group consisting of polyester, polyurethane, polyamide, polyvinyl alcohol, polyvinyl chloride, polyvinylidene chloride, acrylonitrile, polypropylene, polyacryl, and a combination thereof. 
     
     
         16 . The method of  claim 8 , wherein the hydrophobic material is one selected from the group consisting of hexamethyldisiloxane (HMDSO), molybdenum disulfide (MoS 2 ), boron nitride (BN), polytetra fluoroethylene (PTFE), fluorinated diamond like carbon (F-DLC), and a combination thereof. 
     
     
         17 . A fiber product comprising:
 a nano-needle fiber having a surface comprising needle-shaped nano structures; and   a coating layer disposed on the surface comprising needle-shaped nanostructures, and containing a hydrophobic material;   wherein the needle-shaped nano structure has a height of 50 to 150 nm and a width of 5 to 20 nm, and comprises 2 million to 4 million needles per 1 mm 2  of a surface area of the fiber.   
     
     
         18 . The fiber product of  claim 17 , wherein the fiber product is one selected from the group consisting of a tent, an umbrella, shoes, a banner, a cap, a bag, a knapsack, and clothes.