Stamper for microneedle sheet, production method thereof, and microneedle production method using stamper

Abstract

Microneedle sheets are produced by injecting a needle raw material into a stamper formed with a concavity in a base material. However, because the stamper concavity is very small, there is the problem that air cannot escape due to air and surface tension of the material, thereby preventing a needle from being formed in part. The present invention provides a stamper for producing a microneedle sheet. The stamper comprises a sheet-like base material including a conical concavity formed from a first surface of the sheet-like base material toward a second surface thereof; and a through-hole formed from a bottom of the concavity toward the second surface. Air can escape via this through-hole, allowing a microneedle sheet which is filled with a needle raw material as far as the bottom of the concavity to be obtained.

1 . A stamper for producing a microneedle sheet formed on a fixing substrate, the stamper comprising a sheet-like base material including:
 a conical concavity formed from a first surface of the sheet-like base material toward a second surface thereof; and   a through-hole formed from a bottom of the concavity toward the second surface.   
     
     
         2 . A method for producing a stamper for a microneedle sheet formed on a fixing substrate, the method comprising the steps of:
 forming a conical concavity from a first surface of a sheet-like base material toward a second surface of the base material; and   forming a through-hole from a bottom of the concavity toward the second surface.   
     
     
         3 . The method for producing a stamper according to  claim 2 , wherein
 the step of forming a concavity is a step of pressing an original plate having a conical convexity against the first surface of the sheet-like base material and bringing it into contact with the first surface, and wherein   the step of forming a through-hole is a step of perforating the second surface of the base material with a tip of the convexity of the original plate pressed against and brought into contact with the base material.   
     
     
         4 . The method for producing a stamper according to  claim 3 , wherein the step of pressing the original plate against the first surface and bringing it into contact with the first surface is a step of preparing the base material made of a resin, heating the original plate and pressing the heated original plate against the base material and bringing it into contact with the base material. 
     
     
         5 . A method for producing a microneedle sheet formed on a fixing substrate, the method comprising the steps of:
 forming a conical concavity from a first surface of a sheet-like base material toward a second surface of the base material;   forming a through-hole from a bottom of the concavity toward the second surface to obtain a sheet-like stamper;   injecting a needle raw material from the first surface of the stamper; and   sticking a fixing substrate on the first surface.   
     
     
         6 . The method for producing a microneedle sheet according to  claim 5 , wherein
 the step of injecting a needle raw material includes a step of first injecting a first needle raw material and then a step of injecting at least a second needle raw material.   
     
     
         7 . The method for producing a microneedle sheet according to  claim 5 , wherein
 the step of injecting the needle raw material is a step of injecting while applying a pressure to the stamper from the first surface side.   
     
     
         8 . The method for producing a microneedle sheet according to  claim 5 , wherein
 the step of injecting the needle raw material is a step of injecting while sucking the stamper from the second surface side.   
     
     
         9 . The method for producing a microneedle sheet according to  claim 6 , wherein
 the step of injecting the needle raw material is a step of injecting while applying a pressure to the stamper from the first surface side.   
     
     
         10 . The method for producing a microneedle sheet according to  claim 6 , wherein
 the step of injecting the needle raw material is a step of injecting while sucking the stamper from the second surface side.