Transdermal administration device
A plurality of projections in a transdermal administration device each include a columnar portion extending from a first surface of a substrate, and a tapered portion extending from a top of the columnar portion. A maximum angle of an apex of the tapered portion viewed in a direction parallel with the first surface is in a range of 10° or more and 30° or less, a ratio of a length from a proximal end to a distal end of the tapered portion to a length from a proximal end to a distal end of the projection as viewed in a direction perpendicular to the first surface is in a range of 0.45 or more and 0.75 or less, and a pitch (distance between centers of closest projections), viewed in a direction perpendicular to the first surface is in a range of 50 μm or more and 350 μm or less.
1. A transdermal administration device, comprising:
a substrate having a first surface; and
a plurality of projections extending from the first surface, each projection including a columnar portion having a columnar shape extending from the first surface and a tapered portion having a tapered shape extending from a top of the columnar portion, wherein
in each of the plurality of projections,
a maximum angle of an apex of the tapered portion as viewed in a direction parallel with the first surface is in a range of 10° or more and 30° or less,
a ratio of a taper length to a projection length is in a range of 0.45 or more and 0.75 or less, wherein the projection length is a length from a proximal end to a distal end of the projection in a direction perpendicular to the first surface, and the taper length is a length of from a proximal end to a distal end of the tapered portion in a direction perpendicular to the first surface, and
a pitch, which is a distance between a center of one of the projections and a center of another projection closest to the one of the projections, is in a range of 50 μm or more and 350 μm or less, wherein the center of the projection is a center of gravity of a shape of an outline of the projection as viewed in a direction perpendicular to the first surface.
2. The transdermal administration device of claim 1 , wherein the columnar portion has a cylindrical shape and the tapered portion has a conical shape.
3. The transdermal administration device of claim 1 , wherein the columnar portion has a quadrangular prism shape and the tapered portion has a quadrangular pyramid shape.
4. The transdermal administration device of claim 1 , wherein the plurality of projections are arranged in matrix as viewed in a direction perpendicular to the first surface, and the pitch is a distance between the centers of the projections which are adjacent to each other in two directions perpendicular to each other on the first surface.
5. The transdermal administration device of claim 1 , wherein the projection is made of a material including a water-soluble polymer.
6. The transdermal administration device of claim 1 , wherein each projection of said plurality comprises (a) a first portion which includes the distal end of the projection and (b) a second portion which includes the proximal end of the projection, wherein first portions of each projection of said plurality constitute a first layer that is made of a first material, and second portions of each projection of said plurality portion of the projection and the substrate constitute a second layer that is made of a second material, which is different in composition from the first material.
7. The transdermal administration device of claim 6 , wherein the second layer comprises silicon and the first layer comprises a water soluble polymer.
8. The transdermal administration device of claim 7 , wherein the water soluble polymer is selected from carboxymethyl cellulose (CMC), methylcellulose (MC), hydroxylpropyl cellulose (HPC), hydroxypropyl methylcellulose (HPMC), polyvinyl alcohol (PVA), polyacrylic acid polymer, polyacrylic amide (PAM), polyethylene oxide (PEO), pullulan, alginate, pectin, chitosan, chitosan succinamide, and oligochitosan.
9. The transdermal administration device of claim 6 , wherein the second layer comprises silicon and the first layer comprises hydroxypropyl cellulose, chitosan succinamide or cyclic olefin copolymer.