Electrospinning apparatus and method for producing fiber assembly

Abstract

An electrospinning apparatus for depositing fibers on a target having first and second surfaces opposed to each other. The apparatus includes a discharger that discharges a material solution of the fibers towards the first surface of the target, a collector electrode containing a top portion opposed to the discharger, a holder that holds the target between the discharger and the collector electrode so that the first surface of the target is opposed to the discharger, a power supply, a shift regulator that shifts the holder in a direction parallel to the first surface of the target, a distance regulator that regulates a target distance between the top portion of the collector electrode and the second surface of the target, and a controller that controls the shift regulator and the distance regulator to produce a fiber assembly having a given deposited condition on the first surface of the target.

What is claimed is: 
     
         1 . An electrospinning apparatus for depositing fibers on a target having first and second surfaces opposed to each other, the electrospinning apparatus comprising:
 a discharger that discharges a material solution of the fibers towards the first surface of the target;   a collector electrode containing a base portion and a top portion opposed to the discharger;   a holder that holds the target between the discharger and the collector electrode so that the first surface of the target is opposed to the discharger;   a power supply that applies a voltage between the discharger and the collector electrode;   a shift regulator that shifts the holder in a direction parallel to the first surface of the target;   a distance regulator that regulates a target distance between the top portion of the collector electrode and the second surface of the target; and   a controller that controls the shift regulator and the distance regulator to produce a fiber assembly having a given deposited condition on the first surface of the target.   
     
     
         2 . The electrospinning apparatus according to  claim 1 , wherein the distance regulator regulates the target distance by moving the holder. 
     
     
         3 . The electrospinning apparatus according to  claim 1 , wherein the distance regulator changes the target distance by moving the collector electrode. 
     
     
         4 . The electrospinning apparatus according to  claim 1 , wherein a first direction extending from the discharger to the top portion of the collector electrode is unchanged, while the material solution is discharged from the discharger. 
     
     
         5 . The electrospinning apparatus according to  claim 4 , wherein the first direction is inclined to a direction perpendicular to the first surface at an acute angle of 20 degrees or less. 
     
     
         6 . The electrospinning apparatus according to  claim 1 , wherein the shift regulator shifts the holder while maintaining the target distance unchanged. 
     
     
         7 . The electrospinning apparatus according to  claim 1 ,
 wherein the first surface of the target has a deposition section allowing the fiber to be deposited and a non-deposition section surrounding the deposition section, and   wherein the holder holds the target at least partially with either one of the non-deposition section on the first surface and a section on the second surface that is opposed to the non-deposition section on the first surface.   
     
     
         8 . The electrospinning apparatus according to  claim 1 ,
 wherein the discharger defines a first flow channel for guiding the material solution to a first discharging outlet for discharging the material solution therefrom towards the target, and a second flow channel isolated from the first flow channel for guiding a gas to a second flow channel for discharging the gas therefrom towards the target, and   wherein the second discharging outlet is defined so as to surround the first discharging outlet or the first flow channel.   
     
     
         9 . A method for producing a fiber assembly, comprising steps of:
 preparing a material solution containing a raw material of fibers;   preparing a target having first and second surfaces opposed to each other;   holding the target between a discharger and a collector electrode so that the first surface of the target is opposed to the discharger, the collector electrode containing a base portion and a top portion opposed to the discharger;   electrospinning a fiber to form a fiber assembly having a given deposited condition on the first surface of the target by:   i) applying a voltage between the discharger and the collector electrode,   ii) discharging the material solution of the fibers towards the first surface of the target,   iii) shifting the target in a direction parallel to the first surface thereof, and   iv) regulating a target distance between the top portion of the collector electrode and the second surface of the target.   
     
     
         10 . The method for producing the fiber assembly according to  claim 9 , wherein the target distance is regulated by moving the holder. 
     
     
         11 . The method for producing the fiber assembly according to  claim 9 , wherein the target distance is regulated by moving the collector electrode. 
     
     
         12 . The method for producing the fiber assembly according  claim 9 , wherein a first direction extending from the discharger to the top portion of the collector electrode is unchanged, while the material solution is discharged from the discharger. 
     
     
         13 . The method for producing the fiber assembly according to  claim 12 , wherein the first direction is inclined to a direction perpendicular to the first surface at an acute angle of 20 degrees or less. 
     
     
         14 . The method for producing the fiber assembly according  claim 9 , wherein a holder holding the target is shifted while maintaining the target distance unchanged. 
     
     
         15 . The method for producing the fiber assembly according to  claim 9 , wherein
 wherein the first surface of the target has a deposition section allowing the fiber to be deposited and a non-deposition section surrounding the deposition section, and   wherein a holder holds the target at least partially with either one of the non-deposition section on the first surface and a section on the second surface that is opposed to the non-deposition section on the first surface.