JP6560154B2 - Mold manufacturing method and pattern sheet manufacturing method - Google Patents

Description

  The present invention relates to a mold manufacturing method and a pattern sheet manufacturing method.

  In recent years, a micro-needle array (Micro-Needle Array) has been known as a new dosage form capable of administering drugs such as insulin, vaccine (Vaccines), and hGH (human growth hormone) into the skin without pain. ing. The microneedle array is an array of biodegradable microneedles (also referred to as microneedles or microneedles) containing a drug. By affixing this microneedle array to the skin, each microneedle pierces the skin, the microneedle is absorbed in the skin, and the drug contained in each microneedle can be administered into the skin. The microneedle array is also called a transdermal absorption sheet.

  In order to produce a molded product having a fine pattern such as the microneedle array as described above, a resin-inverted mold can be formed from an original plate having a fine pattern, and the molded product can be produced from this mold. Has been done. There is a demand for improving the productivity of molded products having such fine patterns, and various proposals have been made.

  In Patent Document 1, a resin sheet having a surface shape with a fine concavo-convex structure is used, in which the gate width is 90% or more of the width of the molded sheet, and the thickness of the smallest gate thickness is 1.2 mm or less. It is disclosed that molding is performed by injection molding using a certain mold.

  Patent Document 2 describes that the stamper 1 may be formed by a method such as injection molding in which a mold is made of a resin melted in an original plate.

  Patent Document 3 discloses that a mold having a microneedle cavity is produced by injection molding.

JP-A-8-108443 JP 2013-074924 A JP 2010-094414 A

  Patent Documents 1 to 3 disclose that a molded product having a fine pattern is produced by injection molding. However, in general, in injection molding, since a resin is injected into a mold under a high pressure, a fine pattern such as a needle-like pattern formed in the mold may be damaged by the pressure of the resin.

  This invention is made | formed in view of such a situation, and it aims at providing the manufacturing method of the mold which can reduce the damage to a needle-like pattern, and the manufacturing method of a pattern sheet | seat.

  According to one aspect of the present invention, a method for manufacturing a mold includes a mold having a first mold and a second mold, the needle shape protruding into a cavity formed by clamping the first mold and the second mold. A preparatory step for preparing a mold having a first mold provided with a pattern, and clamping the first mold and the second mold, and then a weir disposed between the needle-shaped pattern and the gate communicating with the cavity And an injection step of injecting the resin from the gate to the cavity while restricting the flow of the resin to the tip portion of the needle-like pattern by the member.

  Preferably, the weir member protrudes from the surface of the mold cavity side toward the root side of the needle-like pattern.

  Preferably, the dam member is provided in the second mold.

  Preferably, in the injection process, the amount of protrusion of the weir member from the surface of the mold on the cavity side is controlled according to the injection state of the resin.

  Preferably, in the injection step, the surface on the cavity side of the mold and the weir member are flush with each other before the resin has been injected into the cavity.

  Preferably, before injecting the resin into the cavity, the needle-like pattern and the weir member overlap except for the root portion of the needle-like pattern when viewed from the resin flow direction.

  Preferably, the height of the base portion of the needle-shaped pattern is 0.1 mm or more and 1/2 or less of the height of the needle-shaped pattern.

  Preferably, the gate communicates with a resin flow channel pipe having a flow expanding portion extending in the width direction of the mold.

  Preferably, the resin is a silicone resin.

  Preferably, after the resin is filled in the cavity, the resin in the cavity is cured by heating, the first mold and the second mold are opened, and the cured resin is released from the acicular pattern. Have

  Preferably, the preparing step includes preparing a plurality of first molds having a needle-like pattern, and in the releasing step, while releasing the resin cured from one first mold from the needle-like pattern, The injection process is performed using the first mold.

  Preferably, the releasing step includes moving the peripheral portion of the cured resin in a direction away from the needle-like pattern.

  Preferably, the needle-like pattern provided in the first mold is manufactured by an electroforming method.

  According to another aspect of the present invention, a pattern sheet manufacturing method includes a step of manufacturing a mold by the above-described mold manufacturing method, a supplying step of supplying a polymer solution to the concave pattern of the mold, and drying the polymer solution. And a drying step for forming a polymer sheet, and a polymer sheet releasing step for releasing the polymer sheet from the mold.

  Preferably, the polymer solution includes a water-soluble material.

  According to the mold manufacturing method of the present invention, it is possible to reduce damage to the needle-like pattern formed on the mold.

It is sectional drawing of a type | mold. It is a top view of a type | mold. It is the elements on larger scale of a type | mold. It is the elements on larger scale of another type | mold. It is the elements on larger scale of another type | mold. It is the elements on larger scale of another type | mold. It is process drawing which shows the production method of the mold by the type | mold to which a dam member can move. It is process drawing which shows the production method of the mold by the type | mold to which a dam member can move. It is process drawing which shows the production method of the mold by the type | mold to which a dam member can move. It is process drawing which shows the production method of the mold by the other type | mold to which a dam member can move. It is process drawing which shows the production method of the mold by the other type | mold to which a dam member can move. It is process drawing which shows the production method of the mold by the other type | mold to which a dam member can move. It is a schematic external view of a type | mold. It is process drawing which shows a mold release process. It is process drawing which shows a mold release process. It is process drawing which shows a mold release process. It is process drawing which shows a mold release process. It is process drawing which shows a mold release process. It is sectional drawing of the type | mold using an electroforming mold. It is sectional drawing of the type | mold using an electroforming mold. It is process drawing which shows the preparation methods of the mold which uses several 1st type | molds. It is process drawing which shows the preparation methods of the mold which uses several 1st type | molds. It is process drawing which shows the preparation methods of the mold which uses several 1st type | molds. It is process drawing which shows the preparation methods of the mold which uses several 1st type | molds. It is process drawing which shows the manufacturing method of a pattern sheet. It is process drawing which shows the manufacturing method of a pattern sheet. It is process drawing which shows the manufacturing method of a pattern sheet. It is process drawing which shows the manufacturing method of a pattern sheet. It is process drawing which shows the manufacturing method of a pattern sheet. It is process drawing which shows the manufacturing method of a pattern sheet.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. The invention is illustrated by the following preferred embodiments. Changes can be made by many techniques without departing from the scope of the present invention, and other embodiments than the present embodiment can be utilized. Accordingly, all modifications within the scope of the present invention are included in the claims.

  Here, in the drawing, portions indicated by the same symbols are similar elements having similar functions. In addition, in the present specification, when a numerical range is expressed using “˜”, upper and lower numerical values indicated by “˜” are also included in the numerical range.

<Mold production method>
Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of a mold used for injection molding, and FIG. 2 is a plan view of the mold. FIG. 3 is a partially enlarged view of the mold.

  As shown in FIG. 1, the mold 10 includes a first mold 12 and a second mold 14 that can be opened and closed. The cavity 16 is formed by clamping the first mold 12 and the second mold 14. The cavity 16 means a space part filled with resin.

  The first mold 12 is provided with a needle-like pattern 18 protruding into the cavity 16. The acicular pattern 18 refers to a state in which a plurality of acicular protrusions 18A are arranged at a predetermined number and position. The acicular protrusion 18A means a tapered shape on the distal end side, and includes a cone shape and a multistage cone shape. The multi-stage cone shape means a cone shape having side surfaces with different angles from the bottom surface to the tip.

  As will be described later, by injecting resin into the cavity 16 of the mold 10, a mold having a concave pattern that is an inverted shape of the needle-like pattern 18 is produced. The concave pattern means a state in which a plurality of concave portions extending from one surface to the other surface are arranged, and the number of concave portions, the arrangement of the concave portions, the depth of the concave portions, etc. are not limited.

  A gate 20 communicating with the cavity 16 is formed in the second mold 14. The gate 20 serves as a resin injection port into the cavity 16 of the mold 10. The gate 20 is communicated with an injection molding machine 24 through a resin flow path tube 22.

  The mold 10 of the present embodiment is disposed between the needle-like pattern 18 and the gate 20, and is the surface of the mold 10 on the side of the cavity 16 (so-called inner surface of the mold 10), here, the cavity 16 of the second mold 14. The dam member 26 protrudes from the surface on the side toward the base side of the needle-like pattern 18.

  The weir member 26 is a member that is disposed between the needle-like pattern 18 and the gate 20 that communicates with the cavity 16, and is a member that can restrict the flow of resin to the tip of the needle-like pattern 18. The shape, size, thickness, material, and the like of the weir member 26 are not limited as long as they are members that can restrict the flow of resin to the tip of the needle-like pattern 18.

  In the present embodiment, the dam member 26 is provided in the second mold 14. By providing the weir member 26 in the second mold 14 where the needle-like pattern 18 is not provided, it is possible to suppress the concentration of the resin flow of the needle-like pattern 18. As will be described later, since the weir member 26 restricts the flow of resin to the tip of the needle-like pattern 18, the resin injected into the cavity 16 from the gate 20 directly hits the tip of the needle-like pattern 18. Suppress. Since the weir member 26 relieves the pressure of the resin on the needle-shaped pattern 18, the weir member 26 prevents the needle-shaped pattern 18 from being damaged due to the pressure of the resin.

  As shown in FIG. 2, the length in the width direction of the weir member 26 is preferably longer than the width direction of the needle pattern 18. More reliably, the needle-like pattern 18 can be prevented from being damaged. Here, the width direction means a direction orthogonal to the resin flow direction when the mold 10 is viewed in plan.

  At both ends in the width direction of the weir member 26, a gap S1 is formed between the dam member 26 and the mold 10, and the gap S1 allows the resin to flow into the needle pattern 18 side when the resin is injected from the gate 20 into the cavity 16. A flow path is defined.

  The weir member 26 is preferably a metal having rigidity such as stainless steel. Moreover, it is preferable that the dam member 26 has a thickness that does not deform due to the pressure of resin inflow, for example, 1 mm or more.

  Next, a preferred arrangement of the needle-like pattern 18 and the weir member 26 will be described based on FIG.

  The height H1 of the needle-like protrusion 18A is, for example, in the range of 0.2 mm to 2 mm, and preferably 0.3 mm to 1.5 mm.

  The distance L between the weir member 26 and the needle-like protrusion 18A closest to the weir member 26 is preferably 0.5 mm or more and 1 mm or less. This is to avoid contact between the weir member 26 and the needle pattern 18. The distance L means the shortest distance between the weir member 26 and the needle-like protrusion 18A.

  Further, the height H2 of the cavity 16 is preferably higher in the range of 0.2 mm or more and 0.4 mm or less than the height of the needle-like protrusion 18A.

  It is preferable that the weir member 26 is upstream of the needle-like pattern 18 and overlaps except for the root portion of the needle-like pattern 18 when viewed from the resin flow direction indicated by the arrow, that is, in a projected view. With this arrangement, the weir member 26 intersects with a plane including at least the tip of the needle pattern 18. Therefore, the tip of the needle pattern 18 can be protected from the pressure of the resin and can be prevented from being damaged.

  Here, the root portion of the needle-like pattern 18 means a gap S <b> 2 from the surface on the cavity 16 side of the first mold 12 to the weir member 26. The gap S2 defines a flow path for allowing the resin to flow into the needle pattern 18 side when the resin is injected from the gate 20 into the cavity 16.

  The height (gap S2) of the root portion of the needle-shaped pattern 18 is preferably 0.1 mm or more and 1/2 or less of H1. By setting it as this range, resin can be easily flowed into the needle-like pattern 18 side. In consideration of conditions such as the viscosity of the resin and the injection speed of the resin, it is preferable to appropriately set the height of the root portion (gap S2) of the needle-like pattern 18 by injecting the resin into the cavity 16. For example, the height of the root portion (gap S <b> 2) of the needle-like pattern 18 can be set in a range from a distance at which the dam member 26 does not contact the first mold 12 to a distance less than the height of the needle-like pattern 18.

  Next, a modification of the mold 10 shown in FIG. 3 will be described with reference to FIG. As shown in FIG. 4, the mold 10 includes a first mold 12 and a second mold 14 that can be opened and closed. The cavity 16 is formed by clamping the first mold 12 and the second mold 14.

  A gate 20 communicating with the cavity 16 is formed in the second mold 14. The gate 20 serves as a resin injection port into the cavity 16 of the mold 10. The gate 20 is communicated with an injection molding machine 24 through a resin flow path tube 22.

  The first mold 12 is provided with a needle-like pattern 18 protruding into the cavity 16. The second mold 14 is provided with a weir member 26 disposed between the needle-shaped pattern 18 and the gate 20 and protruding from the surface of the second mold 14 on the cavity 16 side toward the root side of the needle-shaped pattern 18. .

  In the present embodiment, the second mold 14 includes an extension portion 22 </ b> B that extends continuously from the resin flow channel pipe 22 to the cavity 16. Resin R (not shown) is guided to the surface of the first mold 12 by the extension 22B. Therefore, it is possible to more effectively suppress the resin R from directly hitting the tip of the needle-like pattern 18.

  Next, a modification of the mold 10 shown in FIG. 3 will be described with reference to FIG. As shown in FIG. 5, the mold 10 includes a first mold 12 and a second mold 14 that can be opened and closed. The cavity 16 is formed by clamping the first mold 12 and the second mold 14.

  A gate 20 communicating with the cavity 16 is formed in the first mold 12. The gate 20 serves as a resin injection port into the cavity 16 of the mold 10. The gate 20 is in communication with the injection molding machine 24.

  The first mold 12 is provided with a needle-like pattern 18 protruding into the cavity 16. The second mold 14 is provided with a weir member 26 disposed between the needle-shaped pattern 18 and the gate 20 and protruding from the surface of the second mold 14 on the cavity 16 side toward the root side of the needle-shaped pattern 18. .

  In the present embodiment, the first mold 12 is provided with the gate 20, and the injection molding machine 24 communicates with the gate 20, so the resin R (not shown) is in a direction substantially orthogonal to the needle-like pattern 18. To the cavity 16. Since the weir member 26 protruding from the surface of the second mold 14 on the cavity 16 side toward the root of the needle pattern 18 is provided, the resin R is injected from a direction substantially orthogonal to the needle pattern 18. Even in such a case, it is possible to prevent the resin R from directly hitting the tip of the needle-like pattern 18.

  Next, a modification of the mold 10 shown in FIG. 3 will be described with reference to FIG. As shown in FIG. 6, the mold 10 includes a first mold 12 and a second mold 14 that can be opened and closed. The cavity 16 is formed by clamping the first mold 12 and the second mold 14.

  A gate 20 communicating with the cavity 16 is formed in the first mold 12. The gate 20 serves as a resin injection port into the cavity 16 of the mold 10. The gate 20 is in communication with the injection molding machine 24.

  The first mold 12 is provided with a needle-like pattern 18 protruding into the cavity 16. The first mold 12 is provided with a weir member 26 disposed between the needle-shaped pattern 18 and the gate 20 and protruding from the surface of the second mold 14 on the cavity 16 side toward the root side of the needle-shaped pattern 18. .

  In the present embodiment, the first mold 12 is provided with a dam member 26, and the dam member 26 is provided with a through hole 26 </ b> A at a position corresponding to the root portion of the needle-like pattern 18. Since the resin R (not shown) is injected into the cavity 16 through the through hole 26A of the weir member 26, even when the resin R is injected from a direction substantially orthogonal to the needle-like pattern 18, the resin R It is possible to suppress direct contact with the tip of the needle pattern 18.

  Next, the mold 10 capable of adjusting the position of the weir member 26 and a mold manufacturing method using the mold 10 will be described. 7 to 9 are schematic partial cross-sectional views illustrating a method for producing a mold using a mold in which the weir member is movable. 10 to 12 are schematic partial cross-sectional views showing a method for producing a mold using another mold in which the weir member is movable.

  It is preferable that the dam member 26 provided in the mold 10 is provided so that the position can be adjusted. By adjusting the position of the weir member 26, the needle-like pattern 18 can protect the tip portion from the pressure of the resin, and the manufactured mold can be prevented from having an unnecessary step.

  As shown in FIG. 7, the weir member 26 is provided so as to be able to control the amount of protrusion from the surface of the mold 10 on the side of the cavity 16, here the surface of the second mold 14 on the side of the cavity 16. The position of the weir member 26 can be adjusted by projecting the weir member 26 into the cavity 16 or pulling it out of the cavity 16.

  In the dam member 26, a plurality of grooves 30 extending in a direction orthogonal to the moving direction are formed in parallel. A gear 32 is disposed at a position where it engages with the groove 30. The weir member 26 having the plurality of grooves 30 and the gear 32 are in a rack-and-pinion relationship.

  Therefore, the rotational movement of the gear 32 is converted into the linear movement of the weir member 26 having the plurality of grooves 30. By this operation, the weir member 26 can be protruded into the cavity 16 or pulled out from the cavity 16 by the rotation of the gear 32. Further, by adding a scale or the like to the weir member 26, the position of the weir member 26 can be grasped, and the position of the weir member 26 can be easily reproduced.

  As shown in FIG. 7, first, a mold 10 having a first mold 12 and a second mold 14 is prepared (preparation process). Next, the first mold 12 and the second mold 14 are clamped, and the resin R is injected from the injection molding machine 24 into the cavity 16 through the gate 20. In the initial stage of the injection start, the weir member 26 is arranged at a position where the height of the root portion (gap S2: not shown) of the needle-like pattern 18 is set. Resin R flows into the needle-shaped pattern 18 through a gap S1 (not shown) in the width direction between the weir member 26 and the mold 10 and a gap S2 between the weir member 26 and the first mold 12. That is, the resin R is injected from the gate 20 into the cavity 16 while restricting the flow of the resin R to the tip of the needle pattern 18 by the dam member 26 (injection process). The resin R flows in while passing between the needle-like patterns 18. The resin R is preferably a thermosetting resin, and particularly preferably a silicone resin.

  As shown in FIG. 8, the position of the weir member 26 is fixed until the resin R reaches the tip of the needle-like pattern 18.

  As shown in FIG. 9, when the resin R reaches the tip of the needle-like pattern 18, the weir member 26 is pulled out of the cavity 16 by the rotational movement of the gear 32, and the surface of the mold 10 on the cavity 16 side and the weir member 26 is adjusted to the same plane. This operation is performed before the resin R is completely injected into the cavity 16. The cavity 16 side surface of the mold 10 and the weir member 26 are flush with each other, and the resin R is filled in the entire cavity 16. “Before the injection of the resin R” means before the resin R is completely filled in the cavity 16.

  The surface of the mold 10 on the side of the cavity 16 and the weir member 26 are flush with each other when the surface of the mold 10 on the side of the cavity 16 and the weir member 26 are not stepped or in a mold that is a molded product. Including the case of having a step. By making the surface on the cavity 16 side of the mold 10 and the weir member 26 flush with each other, it is possible to avoid unnecessary steps from being formed in the mold.

  When the resin R has been injected into the cavity 16 of the mold 10, as will be described later, the resin R is cured by heating, and the cured resin is released from the mold 10.

  In the present embodiment, the case where the position of the dam member 26 is fixed until the resin R reaches the tip of the needle-like pattern 18 is shown, but the present invention is not limited to this, and depending on the injection state of the resin R, The protruding amount of the weir member 26 can also be controlled. The protruding amount means the length from the surface on the cavity 16 side of the mold 10 where the dam member 26 is disposed to the tip of the dam member 26. By controlling the protruding amount of the weir member 26, the mold can be manufactured under the optimum conditions in consideration of the viscosity of the resin R, the pressure of the resin R, and the shape of the needle pattern 18.

  The injection state of the resin R means the filling amount of the resin R into the cavity 16. The relationship between the filling amount of the resin R and the position of the tip portion of the needle pattern 18 is important.

  Further, by applying a coating (welding) of Teflon (registered trademark) on the side surface of the dam member 26 and in contact with the second mold 14, the side surface of the dam member 26 and the wall surface of the second mold 14 It is preferable that the sliding of the resin R can be made smooth and the resin R does not enter between the weir member 26 and the second mold 14.

  As shown in FIG. 10, the weir member 26 is provided so as to be able to translate in the cavity 16 in the resin flow direction. The weir member 26 is provided with three shafts 40 on the surface opposite to the surface facing the needle pattern 18.

  As shown in FIG. 11, the three shafts 40 are provided at the center of the dam member 26 and on the left and right sides thereof. The three shafts 40 penetrate the first mold 12 and protrude from the cavity 16 to the outside of the mold 10. The three shafts 40 are connected to a driving device (not shown). By the driving device, the weir member 26 is moved in the cavity 16 in a direction parallel to the resin flow direction, in a direction approaching the needle-like pattern 18 or away from the needle-like pattern 18. Further, by adding a scale or the like to the shaft 40, the position of the dam member 26 can be grasped, and the position of the dam member 26 can be easily reproduced.

  As shown in FIG. 10, first, a mold 10 having a first mold 12 and a second mold 14 is prepared, the first mold 12 and the second mold 14 are clamped, and a resin R (not shown) is used. It is injected from the injection molding machine 24 into the cavity 16 through the gate 20. In the initial stage of the injection start, the dam member 26 is disposed at a position separated from the needle-like pattern 18 by a distance L set. The resin R flows into the needle pattern 18 through the gap S1 (not shown) and the gap S2. That is, the resin R is injected from the gate 20 into the cavity 16 while restricting the flow of the resin R to the tip of the needle pattern 18 by the dam member 26. The resin R flows in while passing between the needle-like patterns 18. The position of the weir member 26 is fixed until the resin R reaches the tip of the needle-like pattern 18.

  As shown in FIG. 12, when the resin R reaches the tip of the needle-shaped pattern 18, the weir member 26 is moved away from the needle-shaped pattern 18 by the driving device in the direction opposite to the flow direction of the resin R. The weir member 26 is moved to a position in contact with the surface of the mold 10 on the cavity 16 side. This operation is performed before the resin R is completely injected into the cavity 16. The surface on the cavity 16 side and the weir member 26 are brought into contact with each other, and the resin R is filled in the entire cavity 16.

  After the resin R has been injected into the cavity 16 of the mold 10 and filled in the cavity 16, the resin R is cured by heating, and as will be described later, the cured resin R (also referred to as a mold 50) is the mold 10. It is released from.

  FIG. 13 is a schematic external view of the mold. As shown in FIG. 13, the mold 10 is connected to a resin flow channel pipe 22 having a flow expanding portion 22 </ b> A extending in the width direction of the mold 10 through a gate 20 (not shown). It is preferable to inject the resin into the mold 10 while spreading the resin in the width direction by the flow expanding portion 22A. By spreading the resin in the width direction by the flow spreading portion 22A, the pressure of the resin injected into the cavity 16 of the mold 10 can be reduced.

  Next, the mold release process will be described with reference to FIGS. 14-18 is explanatory drawing which shows a mold release process.

  As shown in FIG. 14, in order to release the cured resin R from the needle-like pattern 18, the first mold 12 and the second mold 14 that have been clamped are opened. In the mold opening, the first mold 12 and the second mold 14 are moved so as to be relatively separated from each other. The cured resin R is a mold 50 having a concave pattern before release. Hereinafter, it may be referred to as a mold 50.

  As shown in FIG. 15, the peripheral edge of the mold 50 is separated from the needle-like pattern 18 of the first mold 12. The peripheral portion of the mold 50 only needs to include at least two opposing sides when the mold 50 is viewed in plan, and may include all four sides. The peripheral edge means a region from the outer periphery of the mold 50 to the concave pattern 52.

  As shown in FIG. 16, the peripheral edge of the mold 50 is gradually separated from the first mold 12. When the mold 50 is made of a silicone resin, the mold 50 has an elastic force. Therefore, when the peripheral portion of the mold 50 is gradually separated, the mold 50 is stretched (elastic deformation).

  As shown in FIG. 17, the peripheral edge of the mold 50 is further separated from the first mold 12. Since the mold 50 that has been elastically deformed tries to return to its original shape, the mold 50 shrinks. By utilizing the shrinking force of the mold 50, the mold 50 is released from the needle pattern 18 of the first mold 12. By using the force that the mold 50 tries to shrink as the peeling force, an excessive force is not applied between the mold 50 and the needle-like pattern 18, so that it is possible to suppress mold release defects.

  As shown in FIG. 18, finally, the mold 50 and the needle-like pattern 18 of the first mold 12 are completely released, and the mold 50 having the concave pattern 52 is produced.

  As a method for separating the periphery of the mold 50 from the first mold 12, the first method is to suck the periphery of the surface opposite to the surface on which the concave pattern 52 is formed with suction means, and suction while sucking the periphery. A method of separating the means from the first mold 12 can be mentioned. The second method includes a method in which the peripheral edge of the surface on which the concave pattern 52 is formed is pushed by an ejector pin provided in the first mold 12 to separate the peripheral edge from the first mold 12. Can do.

  Next, the mold 10 using an electroforming mold will be described. 19 and 20 are sectional views of a mold using an electroforming mold. 19 shows the mold 10 in which the first mold 12 and the second mold 14 are opened, and FIG. 20 shows the mold 10 in which the first mold 12 and the second mold 14 are clamped.

  In this embodiment, the 1st type | mold 12 and the acicular pattern 18 are comprised by another member. The acicular pattern 18 is formed on the surface of the electroforming mold 60.

  As shown in FIG. 19, by opening the first mold 12 and the second mold 14 and placing the electroforming mold 60 having the needle-like pattern 18 on the surface of the first mold 12 on the cavity 16 side. The needle 10 is provided on the mold 10.

  By making the so-called mold 10 into a nested structure, for example, the electroforming mold 60 having the needle-like patterns 18 having different shapes can be easily replaced. By preparing a plurality of electroforming molds 60, molds 50 having different concave patterns 52 can be easily manufactured.

  As shown in FIG. 20, a mold having a concave pattern can be manufactured by clamping the first mold 12 and the second mold 14 and injecting resin into the cavity 16.

  When the electroforming mold 60 is placed on the first mold 12, it is preferable to suck the back surface of the electroforming mold 60. The displacement of the electroforming mold 60 can be suppressed.

  The electroforming mold 60 can be manufactured, for example, by the following electroforming method.

  An original plate having the same shape as the needle-like pattern 18 to be formed is prepared. The original plate can be produced by cutting or the like. Based on the original plate, an electroforming mold having an inverted shape of the original plate is produced. Conductive treatment is performed on the mold for electroforming.

  A cathode holding the electroforming mold subjected to the conductive treatment and an anode holding the metal pellet are immersed in an electroforming solution and energized. By separating from the mold for electroforming, the electroforming mold 60 having the needle-like pattern 18 that is the inverted shape of the mold for electroforming can be produced.

  Next, a method for producing the mold 50 using a plurality of first molds 12A and first molds 12B having the needle-like pattern 18 will be described. FIG. 21 to FIG. 24 are process diagrams showing a mold manufacturing method using a plurality of first molds.

  As shown in FIG. 21, a plurality of first molds 12A and first molds 12B having needle-like patterns 18 are prepared. The first mold 12A and the first mold 12B are fixed on the mounting surface of the turntable 64 having the rotation shaft 62 as a central axis. The mold 10 is configured such that the positions of the first mold 12A and the first mold 12B can be switched by rotating the turntable 64.

  The second mold 14 and the first mold 12A communicated with the injection molding machine 24 are clamped, and then the resin R is injected into the mold 10 and the resin R is filled into the cavity 16. The resin R is cured by heat. The first mold 12B on the turntable 64 is not filled with the resin R.

  As shown in FIG. 22, when the resin R is cured, the mold 50 is manufactured. The second mold 14 moves in a direction perpendicular to the mounting surface of the turntable 64 and away from the first mold 12A. The first mold 12A and the second mold 14 are opened.

  As shown in FIG. 23, the positions of the first mold 12 </ b> A and the first mold 12 </ b> B are switched by rotating the turntable 64 around the rotation shaft 62. The cavity 16 is formed by clamping the first mold 12B and the second mold 14.

  As shown in FIG. 24, while the mold 50 is released from the needle-like pattern 18 of the first mold 12A, the resin R is injected into the cavity 16 formed by the first mold 12B and the second mold 14 from the injection molding machine 24. Is ejected. By performing the injection process and the mold release process at different positions, the injection molding machine 24 can be used effectively, so that the throughput when producing the mold 50 can be improved. In the present embodiment, two first molds 12 (12A, 12B) have been described as an example, but three or more first molds 12 can be used.

<Pattern sheet manufacturing method>
Next, a method for producing a pattern sheet using the mold 50 produced by the above production method will be described. 25 to 30 are process diagrams for manufacturing the pattern sheet 70.

<Polymer solution supply process>
FIG. 25 shows a state where the mold 50 is prepared. The mold 50 is manufactured by the above-described mold manufacturing method. A mold 50 shown in FIG. 25 has a plurality of concave patterns 52.

  FIG. 26 is a diagram illustrating a process of supplying the polymer solution 72 to the concave pattern 52 of the mold 50.

  As a material of the polymer solution 72 that forms the pattern sheet 70, it is preferable to use a water-soluble material. As a resin polymer material of the polymer solution 72 used for manufacturing the pattern sheet 70, it is preferable to use a biocompatible resin. Such resins include sugars such as glucose, maltose, pullulan, sodium chondroitin sulfate, sodium hyaluronate, hydroxyethyl starch, proteins such as gelatin, and biodegradable polymers such as polylactic acid and lactic acid / glycolic acid copolymers. It is preferable to use it. Among these materials, gelatin-based materials have adhesiveness with many base materials, and have strong gel strength as a material to be gelled, so that they can be in close contact with the base material. When the pattern sheet 70 is released from the mold 50, the pattern sheet 70 can be released using a base material (not shown), so that it can be suitably used. Although the concentration varies depending on the material, it is preferable that the concentration of the resin polymer in the polymer solution 72 containing no drug is 10 to 50% by mass. The solvent used for dissolution may be volatile even if it is other than warm water, and alcohol such as ethanol can be used. And in the polymer solution 72, it is possible to dissolve together the medicine to be supplied into the body according to the application. The polymer concentration of the polymer solution 72 containing the drug (when the drug itself is a polymer, the concentration of the polymer excluding the drug) is preferably 0 to 30% by mass.

  As a method for preparing the polymer solution 72, when a water-soluble polymer (gelatin or the like) is used, a water-soluble powder may be dissolved in water, and a drug may be added after the dissolution. Alternatively, a water-soluble polymer powder may be put in and dissolved. If it is difficult to dissolve in water, it may be dissolved by heating. The temperature can be appropriately selected depending on the type of the polymer material, but it is preferable to heat at a temperature of about 20 to 40 ° C. as necessary. The viscosity of the polymer solution 72 is preferably 200 mPa · s or less, more preferably 50 mPa · s or less, in the case of a solution containing a drug. In a solution not containing a drug, it is preferably 2000 mPa · s or less, more preferably 500 mPa · s or less. By appropriately adjusting the viscosity of the polymer solution 72, the polymer solution 72 can be easily injected into the concave pattern 52 of the mold 50. For example, the viscosity of the polymer solution 72 can be measured with a capillary tube viscometer, a falling ball viscometer, a rotary viscometer, or a vibration viscometer.

  The chemical | medical agent contained in the polymer solution 72 will not be limited if it has a function as a chemical | medical agent. In particular, it is preferable to select from peptides, proteins, nucleic acids, polysaccharides, vaccines, pharmaceutical compounds belonging to water-soluble low molecular weight compounds, or cosmetic ingredients.

  Examples of the method for injecting the polymer solution 72 into the mold 50 include coating using a spin coater.

  A through hole is preferably formed at the tip of the concave portion of the concave pattern 52 of the mold 50. The air in the concave portion of the concave pattern 52 can be released from the through hole. Therefore, the polymer solution 72 can easily enter the recess of the mold 50. Further, this step is preferably performed in a reduced pressure state.

[Drying process]
FIG. 27 is a diagram illustrating a process of drying the polymer solution 72 to obtain a polymer sheet 74. For example, the polymer solution 72 supplied to the mold 50 can be dried by blowing air. The polymer sheet 74 means a state after the polymer solution 72 is subjected to a desired drying process. The water content of the polymer sheet 74 is set as appropriate. In addition, since it will become difficult to peel when the water content of a polymer becomes too low by drying, it is preferable to leave the water content in the state of maintaining elasticity.

  The polymer sheet 74 is formed with a needle-like pattern 76 that is an inverted shape of the concave pattern 52.

[Polymer sheet release process]
28 and 29 are views showing a state in which the polymer sheet 74 is released from the mold 50 to form a pattern sheet 70. FIG. FIG. 30 is a diagram illustrating a process of cutting the pattern sheet 70 into individual pattern sheets 70A, 70B, and 70C.

  The pattern sheet 70 released from the mold 50 is set in a cutting device (not shown), and a position for cutting the pattern sheet 70 is determined. Basically, the cutting position is determined so as to be in each of the regions 76A, 76B, and 76C having the needle-like pattern 76. As shown in FIG. 30, the pattern sheet 70 is cut into a plurality of individual pattern sheets 70A, 70B, 70C.

  25 to 30, the method for manufacturing the pattern sheet 70 using the mold 50 has been described, but the present invention is not limited to this. For example, an assembly mold in which the area of the concave pattern 52 is increased can be manufactured by bonding a plurality of molds 50. A pattern sheet can also be manufactured using an assembly mold.

  By producing the pattern sheet using the assembly mold, a pattern sheet having a large area can be produced by one production, and productivity can be improved.

  In this embodiment, the case where the polymer sheet 74 is formed by filling the polymer dissolution liquid 72 into the concave pattern 52 of the mold 50 and drying is described, but the present invention is not limited to this.

  For example, a polymer solution containing a drug is filled in the concave pattern 52 of the mold 50 and dried, and then a polymer solution not containing the drug is filled in the concave pattern 52 of the mold 50 and dried, thereby forming a two-layer structure. A polymer sheet 74 can be formed.

  Further, the mold 50 may be used only once for the first time, and may be preferably disposable. When the pattern sheet 70 is used as a medicine, it is preferable to make it disposable in consideration of the safety of the manufactured pattern sheet 70 to the living body. Moreover, since it becomes unnecessary to wash | clean the mold 50 by making it disposable, the cost by washing | cleaning can be reduced. In particular, when the pattern sheet 70 is used as a pharmaceutical product, high cleaning performance is required, which increases the cleaning cost.

  The needle-like pattern 76 (regions 76A, 76B, 76C) of the pattern sheet 70 to be manufactured means a state in which a plurality of needle-like protrusions 78 are arranged at a predetermined number and position. The needle-like protrusion 78 means a tapered shape on the distal end side, and includes a cone shape and a multistage cone shape. The multi-stage cone shape means a cone shape having side surfaces with different angles from the bottom surface to the tip.

  The height of the needle-like protrusion 78 is in the range of 0.2 mm to 2 mm, and preferably 0.3 mm to 1.5 mm.

  The manufactured pattern sheet 70 having the needle-like pattern 76 is a duplicate of the mold 10 having the needle-like pattern 18. By making the shape and arrangement of the needle-like pattern 18 of the mold 10 into a desired shape, the needle-like pattern 76 of the pattern sheet 70 to be manufactured can be made a desired shape.

10 Mold 12, 12A, 12B First mold 14 Second mold 16 Cavity 18 Needle-shaped pattern 18A Needle-shaped protrusion 20 Gate 22 Resin flow pipe 22A Flow expanding section 22B Extension section 24 Injection molding machine 26 Weir member 26A Through hole 30 Groove 32 Gear 40 Shaft 50 Mold 52 Concave pattern 60 Electroforming mold 62 Rotating shaft 64 Turntable 70, 70A, 70B, 70C Pattern sheet 72 Polymer solution 74 Polymer sheet 76 Acicular patterns 76A, 76B, 76C Region 78 Acicular projection H1, H2 Height L Distance R Resin S1, S2 Clearance

Claims (13)

A mold having a first mold and a second mold, the mold having the first mold provided with a needle-like pattern protruding in a cavity formed by clamping the first mold and the second mold A preparation process to prepare,
The first mold and the second mold are clamped, and then the resin flow to the tip of the needle pattern is caused by a dam member arranged between the needle pattern and the gate communicating with the cavity. An injection step of injecting resin from the gate into the cavity while limiting,
In the method for manufacturing a mold having a
The said dam member is a manufacturing method of the mold which protrudes toward the base side of the said acicular pattern from the surface by the side of the said cavity of the said type | mold . The method for producing a mold according to claim 1, wherein the dam member is provided in the second mold. 3. The mold manufacturing method according to claim 1, wherein, in the injection step, the amount of protrusion of the weir member from the surface of the mold on the cavity side is controlled according to the injection state of the resin. The mold manufacturing method according to claim 2 , wherein, in the injection step, the surface of the mold on the cavity side and the weir member are flush with each other before the resin is injected into the cavity. Before injecting the resin into the cavity, the height of the root portion of the acicular pattern is 0.1 mm or more and 1/2 or less of the height of the acicular pattern. The method for producing a mold according to any one of claims 1 to 4 , wherein the weir member overlaps except for a root portion of the needle-like pattern when viewed from the flow direction of the resin. The mold manufacturing method according to any one of claims 1 to 5 , wherein the gate communicates with a resin flow channel pipe having a flow expanding portion that extends in a direction orthogonal to the flow direction of the resin. The method for manufacturing a mold according to any one of claims 1 to 6 wherein the resin is a silicone resin. After the resin is filled in the cavity, the resin in the cavity is cured by heating, the first mold and the second mold are opened, and the cured resin is separated from the needle-like pattern. the method for manufacturing a mold according to any one of claims 1 to 7 having a mold for releasing step. Preparing a plurality of first molds having the needle-like pattern in the preparing step;
The mold according to claim 8 , wherein in the mold releasing step, the injection process is performed using another first mold while the resin cured from one of the first molds is released from the needle-like pattern. Manufacturing method. The method for producing a mold according to claim 8 or 9 , wherein, in the releasing step, the peripheral portion of the cured resin is moved in a direction away from the needle pattern. Wherein the needle-like pattern provided on the first type, the method for manufacturing a mold according to claim 1, any one of 10 to be fabricated by electroforming. A step of producing a mold by the method of producing a mold according to any one of claims 1 to 11 ,
Supplying a polymer solution to the concave pattern of the mold;
A drying step of drying the polymer solution to form a polymer sheet;
A polymer sheet releasing step of releasing the polymer sheet from the mold;
The manufacturing method of the pattern sheet containing this. The method for producing a pattern sheet according to claim 12 , wherein the polymer solution contains a water-soluble material.

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