JP5671241B2 - Mold for annular medical device and annular medical device molded using this mold - Google Patents

Description

  The present invention relates to a mold for an annular medical device having an opening at the center of the medical device, and an annular medical device molded using the mold.

  Conventionally, eye drops have been mainly used as a method for administering ophthalmic drugs to eye tissues. However, since the amount of drugs staying in the eye tissues is smaller than the amount of eye drops, more efficient drug administration methods. Was demanded. As a result, a so-called drug delivery contact lens (DDSCL) has been developed in which a hydrogel contact lens is impregnated with a water-soluble ophthalmic drug and worn on the eye, whereby the drug is gradually released in the eye tissue.

  However, this method only impregnates the drug inside the hydrogel contact lens, and most of the drug is gradually released immediately after wearing, so the controlled release rate of the drug is controlled and the drug is continuously released. There was a further need for technology.

  As a new form of administering this ophthalmic drug to the ocular tissue, a technique is disclosed in which the hydrogel contact lens and the ophthalmic drug are ion-bonded and the drug is gradually released by ion exchange during wearing on the eye. (See Patent Document 1).

JP 2003-301014 A

  However, in the method described in Patent Document 1, since the entire eye surface is covered with a contact lens, a drug having a therapeutically effective concentration is applied to anterior ocular tissues such as cornea and aqueous humor and external ocular tissues such as tears and conjunctiva. However, the lens shape described in Patent Document 1 is sufficient for selectively transferring from the lens to the posterior ocular tissue such as the posterior retina, choroid, sclera, and vitreous. I can't say that.

  Therefore, the inventors of the present application used an annular lens having a shape having an opening at the center as a method for efficiently transferring the ophthalmic drug to the posterior segment tissue. It came to devise the method of contacting the impregnated contact lens.

  However, since this type of annular lens is usually produced by extracting the central portion of the lens by trepan processing, this method requires a high level of processing technology to obtain a lens of constant quality. There was a problem that it was not suitable for mass production.

  Further, the production of contact lenses is generally performed using a lens forming mold, and after injecting a contact lens forming polymerizable monomer into a female mold, the male mold is fitted, It is formed by polymerization by heat or ultraviolet irradiation.

  In this case, if the male and female molds are not completely fitted, a gap will occur at the mating site and burrs will occur at the edges of the molded body. Use the molded body as a contact lens. Can not do it. Further, the molding die has a problem that it is difficult to control the thickness of the contact lens obtained as a molded body when the accuracy of fitting between the male die and the female die is insufficient.

  As described above, in the production of contact lenses using a mold, it is important to improve the accuracy of the fitting part because it greatly affects the quality of the lens in which the male and female fitting states are obtained. Become.

  Then, an object of this invention is to provide the shaping | molding die of the annular medical device which can mass-produce the annular medical device which has an opening part in the center part of a medical device with fixed quality. Another object of the present invention is to provide a mold for forming an annular medical device in which burrs are not generated at the outer and inner diameter edges of the obtained annular medical device and the thickness of the annular medical device can be easily controlled. And Moreover, an object of this invention is to provide the cyclic | annular medical device obtained using this shaping | molding die.

  In order to solve the above problems, the present invention is a molding die formed by combining a female mold and a male mold and molding a medical device using a space generated between the female mold and the male mold. And forming a ring-shaped medical device having a fitting portion between the female die and the male die at two locations of an outer diameter edge and an inner diameter edge of the medical device and having an opening at the center of the medical device. The present invention provides a mold for forming an annular medical device.

  In the annular medical device mold according to the present invention, the annular medical device is formed in a lens shape having a curvature adapted to the curvature of the eye, and the female die is a forming surface corresponding to the front curve surface of the annular medical device. The male mold has a convex shape that provides a forming surface corresponding to the base curve surface of the annular medical device.

  Further, the mold for the annular medical device of the present invention uses a biting structure or a butting structure at two fitting sites of the outer diameter edge and the inner diameter edge, which are constituted by a combination of the female mold and the male mold. It is characterized by that.

  In addition, the mold for the annular medical device of the present invention is configured by a combination of the female mold and the male mold, and one fitting part is a biting structure in two fitting parts of an outer diameter edge and an inner diameter edge. And the other fitting part is a butting structure.

  The mold for an annular medical device of the present invention is characterized in that the annular medical device is formed such that the thickness of the intermediate region is larger than the thickness of the inner edge region and the outer edge region.

  Further, in the annular medical device mold according to the present invention, the annular medical device is formed such that the inner edge region has a thickness of 0.10 to 0.30 mm and the outer edge region has a thickness of 0.15 to 0.35 mm. The intermediate region has a thickness of 0.20 to 0.40 mm.

  The present invention also provides an annular medical device having an opening at the center, which is formed using the molding die described above.

  The mold of the annular medical device of the present invention is a molding die formed by combining a female mold and a male mold, and molding a medical instrument using a space generated between the female mold and the male mold, A fitting part of the female mold and the male mold is provided at two locations of an outer diameter edge and an inner diameter edge of the medical device, and an annular medical device having an opening at the center of the medical device is formed. Therefore, an annular medical device that can efficiently deliver a drug to the posterior eye portion and that has the position and thickness of the opening portion with a certain accuracy corresponding to the design value can be easily manufactured by one molding. Therefore, there is an effect that the annular medical device can be mass-produced while maintaining a certain quality.

  In the annular medical device mold according to the present invention, the annular medical device is formed in a lens shape having a curvature adapted to the curvature of the eye, and the female die is a forming surface corresponding to the front curve surface of the annular medical device. The annular medical device conforms to the curvature of the eye and has a good wearing feeling by forming a concave surface shape that provides a forming surface corresponding to the base curve surface of the annular medical device. There is an effect that can be mass-produced.

  Further, the mold for the annular medical device according to the present invention has a biting structure or / and abutting structure at two fitting sites of the outer diameter edge and the inner diameter edge, which are constituted by a combination of the female mold and the male mold. By using this, it is possible to mass-produce an annular medical device that has a certain accuracy corresponding to the design value, such as the position and thickness of the opening, and that does not generate burrs on the outer and inner diameter edges. There is an effect that an annular medical device having a good feeling can be obtained with a certain quality.

  In addition, the mold for the annular medical device of the present invention is configured by a combination of the female mold and the male mold, and one fitting part is a biting structure in two fitting parts of an outer diameter edge and an inner diameter edge. Because the other fitting part has a butting structure, fluctuations of the female molds generated in both fitting parts due to the pressing force at the time of mating cancel each other, and the position and thickness of the opening etc. The accuracy can be further improved, and the occurrence of burrs on the outer diameter edge and the inner diameter edge can be prevented, thereby improving the quality.

  Moreover, the mold for the annular medical device of the present invention is such that the annular medical device is formed so that the thickness of the intermediate region is thicker than the thickness of the inner edge region and the outer edge region, so that There is an effect that an annular medical device having good stability can be obtained.

  Further, the mold of the annular medical device of the present invention is formed such that the inner edge region of the annular medical device has a thickness of 0.10 to 0.30 mm, and the outer edge region has a thickness of 0.15 to 0.35 mm. By forming the thickness of the region to be 0.20 to 0.40 mm, there is an effect that an annular medical device having good stability on the eyeball during wearing can be obtained.

  The annular medical device of the present invention is an annular medical device having an opening at the center, and has a configuration molded using the molding die described above, thereby efficiently delivering a drug to the posterior segment. An annular medical device having a certain accuracy corresponding to the design value of the position, thickness, etc. of the opening can be easily manufactured by only one molding process, so that the annular quality can be maintained while maintaining a certain quality. There is an effect that mass production of medical devices can be achieved.

Sectional drawing which shows the 1st aspect of the shaping | molding die of the annular medical device of this invention. The expanded sectional view which shows the internal diameter edge fitting part of the shaping | molding die in a 1st aspect. The expanded sectional view which shows the outer diameter edge fitting part of the shaping | molding die in a 1st aspect. Sectional drawing which shows the 2nd aspect of the shaping | molding die of the annular medical device of this invention. The expanded sectional view which shows the internal diameter edge fitting part of the shaping | molding die in a 2nd aspect. The expanded sectional view which shows the outer diameter edge fitting part of the shaping | molding die in a 2nd aspect. Sectional drawing which shows the medical device part in a 1st aspect. Sectional drawing which shows the medical device part in a 2nd aspect. The front view which shows an example of the annular medical device shape | molded using the shaping | molding die of this invention.

  The mold for the annular medical device according to the present invention is formed so that the female device 1 and the male device 2 are combined, and the medical device 3 is formed using a space generated between the female device 1 and the male device 2. In the molding die, the fitting portions 4 and 5 of the female die 1 and the male die 2 are provided at two locations of the outer diameter edge and the inner diameter edge of the medical device 3, and are formed at the center of the medical device 3. An annular medical device 3 having an opening 3a is formed.

  Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view of a state in which a female mold 1 and a male mold 2 are fitted. The mold for the annular medical device according to the present invention has a configuration in which the fitting portions 4 and 5 of both the molds 1 and 2 are provided around the outer diameter edge and the inner diameter edge of the annular medical device 3, respectively. The obtained molded body can be an annular medical device 3 having an opening 3c at the center.

  The molding die used in the present invention is characterized by having fitting parts 4 and 5 at two locations of the outer diameter edge and the inner diameter edge of the annular medical device 3. Therefore, the mold of the present invention is required to have higher fitting accuracy than a normally used contact lens mold having only one portion of the outer diameter edge.

  The mold for the annular medical device according to the present invention preferably applies a biting structure or a butting structure to the structure of the two fitting parts 4, 5. It is more preferable that each of the biting structure and the butting structure is arranged mutually. With this structure, the mold of the present invention can dramatically improve the controllability of the shape and thickness at the fitting parts 4 and 5 of the molded body to be obtained.

  As shown in FIG. 3 (or FIG. 5), the cut-off structure refers to a structure in which the fitting part 5 (or 6) of the male mold 2 and the female mold 1 is contacted in the vertical direction. In addition, as shown in FIG. 2 (or FIG. 6), the butting structure refers to a structure in which the fitting part 4 (or 7) of the male mold 2 and the female mold 1 is contacted in the lateral direction.

  As shown in FIGS. 3 and 5, when the cut-off structure is used for the fitting part, the male mold 2 spreads the female mold 1 in the lateral direction, so that the stability in the vertical direction for controlling the thickness of the molded body is improved. It tends to be lower and the controllability of the thickness is slightly lowered. On the other hand, as shown in FIGS. 2 and 6, when the abutting structure is used, the male mold 2 spreads the female mold 1 in the vertical direction, so that a gap is easily generated in the fitting portions 4 and 7, and the burr is formed. There is a tendency that the occurrence of is slightly more likely to occur. Therefore, when the cut-off structure or the butting structure is used alone for the fitting part, it is necessary to suppress the occurrence of burrs and control the thickness of the molded body by adjusting the fitting position and the fitting pressure.

  In the embodiment shown in FIG. 1 and FIG. 4, the mold of the present invention has a biting structure and an abutting structure arranged on the outer diameter edge fitting parts 5 and 7 and the inner diameter edge fitting parts 4 and 6, respectively. Yes. These molding dies complement the drawbacks of each fitting structure and form an integral fitting structure that interlocks each other structure, so that the female die 1 receives a pressing force from each fitting structure. The occurrence of burrs can be more effectively suppressed, and the thickness of the molded body can be controlled.

  The mold according to the present invention has a biting structure as a fitting structure, or a combination of an outer diameter edge fitting portion and an inner diameter edge fitting portion when a butting structure is used. Two types of butting structures are conceivable. Further, the molding die of the present invention has a butting structure, a biting structure, and a biting structure as a combination of an outer diameter edge fitting portion and an inner diameter edge fitting portion when a fitting structure is used, and an abutting structure is used. Two types of structure-abutting structure are conceivable. As an aspect of the present invention, the embodiment shown in FIG. 1 shows a combination of a biting structure (outer diameter edge fitting portion 5) -abutting structure (inner diameter edge fitting portion 4), and in the embodiment shown in FIG. The combination of the butting structure (outer diameter edge fitting part 7) and the biting structure (inner diameter edge fitting part 6) is shown. By using these structures, the molding die of the present invention can more suitably suppress the generation of burrs and improve the thickness accuracy of the molded body.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but these do not limit the present invention.

  In the embodiment shown in FIG. 1, the annular medical device is an annular lens 3 that is formed in a lens shape having a curvature adapted to the curvature of the eye to be worn and has an opening 3 c at the center. The mold for the annular lens 3 is a combination of the female mold 1 and the male mold 2, and the female mold 1 has a concave shape that provides a formation surface corresponding to the front curve surface (FC surface) 3 a of the annular lens 3. The mold 2 has a convex shape that provides a formation surface corresponding to the base curve surface (BC surface) 3 b of the annular lens 3. The annular lens 3 is molded using a space generated between the female mold 1 and the male mold 2.

  In the molding die of the present invention, the fitting portions 4 and 5 of the female die 1 and the male die 2 are provided around the outer diameter edge and the inner diameter edge of the annular lens 3, and the annular lens 3 is formed only by one molding process. It is comprised so that can be shape | molded. The mold shown in FIG. 1 uses a biting structure for the outer diameter edge fitting portion 5 and uses a butting structure for the inner diameter edge fitting portion 4.

  As shown in FIG. 2, in the abutting structure, the female mold 1 and the male mold 2 are contacted in the lateral direction on the abutting surfaces 4a and 4b. The female die 1 is smoothly connected from the FC surface 3a to the abutting surface 4a formed horizontally via the curved portion 9 formed on the periphery of the inner edge region 14. In the male mold 2, the abutting surface 4b is formed horizontally from the BC surface 3b through a substantially vertical edge portion 8 that forms the inner diameter edge of the annular lens 3. The BC surface 3 b of the male mold 2 and the edge portion 8 are smoothly connected to improve the wearing feeling of the annular lens 3 together with the curved portion 9 of the female mold 1.

  The female mold 1 and the male mold 2 are formed with a monomer reservoir 10 inside the annular abutting surfaces 4a and 4b so as to remove the overflowing lens raw material.

  As shown in FIG. 3, in the biting structure, the female die 1 and the male die 2 are contacted in the vertical direction on the biting surfaces 5a and 5b. The female die 1 is smoothly connected from the FC surface 3a to the biting surface 5a formed vertically through the curved portion 9 formed on the peripheral edge of the outer edge region 16. The male die 2 has a biting surface 5b formed vertically from the BC surface 3b via a substantially horizontal edge portion 8 that forms the outer diameter edge of the annular lens 3. The BC surface 3 b of the male mold 2 and the edge portion 8 are smoothly connected to improve the wearing feeling of the annular lens 3 together with the curved portion 9 of the female mold 1.

  The female mold 1 and the male mold 2 are formed with a monomer reservoir 10 below the cylindrical biting surfaces 5a and 5b so as to remove the overflowing lens raw material. In the embodiment shown in FIG. 1, the female mold 1 is formed such that a cross section of a portion connecting the monomer reservoir 10 to the biting surface 5 a is an R-shaped convex surface. With this configuration, the biting surface 5b of the male mold 2 can gently contact the biting surface 5a of the female mold 1 in the fitting process.

  When the mold of FIG. 1 is used in the fitting part of the mold for the annular medical device of the present invention, the fitting is performed in the order of the outer diameter edge fitting part 5 and the inner diameter edge fitting part 4. In this case, the biting surface 5b of the male mold 2 spreads the biting surface 5a of the female mold 1 in the lateral direction, so that the female mold 1 is entirely spread in the lateral direction. Since it slides in the horizontal direction, fluctuations in the vertical direction occur, making it difficult to control the thickness. However, the mold shown in FIG. 1 uses the structure of the inner diameter edge fitting portion 4 as an abutting structure, and the male mold 2 pushes the female mold 1 in the vertical direction, so that the vertical direction caused by the lateral shift occurs. It became possible to buffer fluctuations. Accordingly, in the mold shown in FIG. 1, the fitting is completed without generating a gap between the outer diameter edge fitting portion 5 and the inner diameter edge fitting portion 4 and without causing a defect in thickness. The annular lens 3 having a certain accuracy corresponding to the design value, the position of the lens, the thickness of the lens, and the like that does not generate burrs on the outer diameter edge and the inner diameter edge can be obtained.

  The mold for the annular medical device according to the present invention can be produced by molten resin molding. The resin composition used as the material of the mold is polypropylene, polyethylene, polyethylene terephthalate, polystyrene, polycarbonate, polyvinyl chloride, polyamide, polyacetal, fluororesin, cycloolefin polymer (trade names: ZEONEX (registered trademark), ZEONOR (registered trademark) ) Nippon Zeon Co., Ltd.) and cyclic olefin copolymers (trade name: Apel (registered trademark) Mitsui Chemicals Co., Ltd.) and other known materials are used, but in consideration of moldability, polyolefins such as polypropylene and polyethylene are more preferably used. It is done.

  The melting temperature during molding is preferably a temperature suitable for the resin composition to be used, and 140 to 400 ° C., which is the melting temperature of the resin composition, is preferable. In the present invention, since polypropylene and polyethylene are preferably used, a more preferable melting temperature is 180 to 290 degrees. Moreover, it is preferable to shape | mold at the pressure at the time of shaping | molding with the pressure suitable for the resin composition to be used, and the pressure suitable for the said resin composition is 30-200 MPa, However, In this invention, polypropylene and polyethylene are used. Since it is preferably used, a more preferable pressure is 70 to 150 MPa.

  The annular lens molded using the mold of the annular medical device of the present invention is an intermediate region between the inner edge region 14 and the outer edge region 16 from the viewpoint of wearing feeling when worn on the eye and stability on the eyeball. It is preferable to form so that 15 becomes the maximum thickness. Here, the inner edge region 14 indicates a width within 0.50 mm from the inner diameter edge of the annular lens 3, preferably 0.30 to 0.50 mm, and more preferably 0.30 mm. The outer edge region 16 refers to a width within 0.50 mm from the outer edge of the annular lens 3, preferably 0.30 to 0.50 mm, and more preferably 0.30 mm. The intermediate region 15 refers to a portion of the annular lens 3 excluding the inner edge region 14 and the outer edge region 16.

  The thickness 11 of the inner edge region 14 is preferably in the range of 0.10 to 0.30 mm, more preferably in the range of 0.13 to 0.23 mm. The thickness 13 of the outer edge region 16 is preferably in the range of 0.15 to 0.30 mm, more preferably in the range of 0.17 to 0.23 mm. The thickness 12 of the intermediate region 15 is preferably in the range of 0.20 to 0.40 mm, and more preferably in the range of 0.33 to 0.38 mm. Since the annular lens 3 has the maximum thickness of the intermediate region 15, it is possible to minimize the effect of eyelid pressure due to blinking, and it is possible to prevent displacement and omission on the eyeball during wearing. In addition, since it is excellent in handling, it can be easily mounted on the eyeball.

  Further, the size of the annular lens 3 is not particularly limited as long as it does not hinder the wearing of the annular medical device and can cover the sclera surface, and the outer diameter thereof is not limited to that on the eyeball. From the viewpoint of wearability and scleral surface coverage, the thickness is preferably about 16 to 20 mm, more preferably about 18 to 20 mm.

  The inner diameter of the annular lens 3, that is, the diameter of the opening 3c is preferably about 10 to 15 mm, more preferably about 12 mm, from the viewpoint of preventing contact with the cornea of the annular medical device (corneal exposure) and long-term wearability. It is.

  The curvature of the base curve (BC) of the annular lens 3 is appropriately selected from the curvature of the sclera, but is usually 8.8 to 13 mm, preferably 10 to 12 mm.

  The annular medical device 3 of the present invention is preferably a hydrogel since a water-soluble drug is included in a lens which is a medical device. That is, the polymerizable monomer used in the annular medical device 3 of the present invention is characterized by containing a so-called hydrophilic monomer having at least one hydrophilic group. As the hydrophilic monomer, a (meth) acryl group-containing monomer and a vinyl group-containing monomer can be used. Specifically, N, N-dimethylacrylamide (DMAA), 2-hydroxyethyl methacrylate (HEMA), (meth) acrylic acid, polyethylene glycol monomethacrylate, glycerol methacrylate, (meth) acryloyloxyethyl phosphate, (meth) acryloyl Oxymethyl phosphate, methacrylamidopropyltrimethylammonium chloride, N-vinylpyrrolidone (NVP), N-vinyl-N-methylacetamide, N-vinyl-N-ethylacetamide, N-vinyl-N-ethylformamide, N-vinylformamide And methacryloxyethyl succinic acid. The other polymerizable monomer that can be blended is not particularly limited as long as it is a monomer that is usually used as a contact lens material and can be used in combination with the hydrophilic monomer, but methyl methacrylate, 2-ethylhexyl methacrylate, etc. (Meth) acrylate monomers, fluorine-containing (meth) acrylate monomers such as 2-trifluoromethyl methacrylate, silicon-containing (meth) acrylate monomers such as tris (trimethylsiloxy) silylpropyl methacrylate, ethylene glycol dimethacrylate, polyethylene Examples thereof include crosslinkable monomers such as glycol dimethacrylate and trimethylolpropane trimethacrylate.

  In the embodiment shown in FIG. 4, the annular medical device is an annular lens 3 that is formed in a lens shape having a curvature adapted to the curvature of the eye to be worn and has an opening 3 c at the center. The mold for the annular lens 3 is a combination of the female mold 1 and the male mold 2, and the female mold 1 has a concave shape that provides a formation surface corresponding to the front curve surface (FC surface) 3 a of the annular lens 3. The mold 2 has a convex shape that provides a formation surface corresponding to the base curve surface (BC surface) 3 b of the annular lens 3. The annular lens 3 is molded using a space generated between the female mold 1 and the male mold 2.

  In the molding die of the present invention, the fitting portions 6 and 7 of the female die 1 and the male die 2 are provided around the outer diameter edge and the inner diameter edge of the annular lens 3, and the annular lens 3 is formed only by one molding process. It is comprised so that can be shape | molded. The molding die shown in FIG. 4 uses an abutting structure for the outer diameter edge fitting portion 7 and uses a biting structure for the inner diameter edge fitting portion 6.

  As shown in FIG. 5, in the biting structure, the female die 1 and the male die 2 are contacted in the vertical direction on the biting surfaces 6a and 6b. The female die 1 is smoothly connected from the FC surface 3a to the substantially horizontal edge portion 8 that forms the inner diameter edge of the annular lens 3 via the curved portion 9 formed on the peripheral edge of the inner edge region 14. Further, a vertical biting surface 6 a is formed at the edge end of the edge portion 8. The male mold 2 is smoothly connected from the BC surface 3 b to the vertical cut-off surface 6 b, and improves the wearing feeling of the annular lens 3 together with the curved portion 9 of the female mold 1.

  The female mold 1 and the male mold 2 are formed with a monomer reservoir 10 inside the cylindrical biting surfaces 6a and 6b so as to remove the overflowing lens raw material. In the embodiment shown in FIG. 4, the male mold 2 is formed such that the cross section of the portion connecting the monomer reservoir 10 to the biting surface 6b is an R-shaped convex surface. With this configuration, the biting surface 6a of the female die 1 can gently come into contact with the biting surface 6b of the male die 2 in the fitting process.

  As shown in FIG. 6, in the abutting structure, the female mold 1 and the male mold 2 are brought into contact in the lateral direction on the abutting surfaces 7a and 7b. The male mold 2 has an abutting surface 7b formed horizontally from the BC surface 3b via a substantially horizontal edge portion 8 that forms the outer diameter edge of the annular lens 3. The female die 1 is smoothly connected from the FC surface 3a to the peripheral portion formed substantially vertically through the curved portion 9 formed on the peripheral portion of the outer edge region 16. In addition, the female die 1 has an abutting surface 7a that is in contact with the abutting surface 7b of the male die 2 formed horizontally at the tip of the peripheral edge. The BC surface 3 b of the male mold 2 and the edge portion 8 are smoothly connected to improve the wearing feeling of the annular lens 3 together with the curved portion 9 of the female mold 1.

  The female mold 1 and the male mold 2 have a space formed outside the annular butting surfaces 7a and 7b so that the overflowing lens raw material is removed.

  When the mold of FIG. 4 is used in the fitting part of the mold for the annular medical device of the present invention, the fitting is performed in the order of the inner diameter edge fitting part 6 and the outer diameter edge fitting part 7. In this case, the biting surface 6b of the male die 2 pushes the biting surface 6a of the female die 1 in the lateral direction, so that the female die 1 is entirely spread in the lateral direction, so that the outer diameter edge fitting portion 7 is expanded. Since it also slides in the horizontal direction, fluctuations in the vertical direction occur, making it difficult to control the thickness. However, the mold shown in FIG. 4 uses the structure of the outer diameter edge fitting portion 7 as an abutment structure, and the male mold 2 pushes the female mold 1 in the vertical direction, thereby causing the vertical direction generated by the lateral displacement. It became possible to buffer fluctuations. Therefore, in the mold shown in FIG. 4, the outer diameter edge fitting portion 7 and the inner diameter edge fitting portion 6 are not fitted with a gap, and the fitting is completed without causing a thickness defect. The annular lens 3 having a certain accuracy corresponding to the design value, the position of the lens, the thickness of the lens, and the like that does not generate burrs on the outer diameter edge and the inner diameter edge can be obtained.

Comparative example

  Hereinafter, in the annular medical device molded according to Examples 1 to 9 shown in Table 1, the presence or absence of burrs on the outer diameter edge and inner diameter edge of the annular lens 3 and the thickness accuracy of the annular lens 3 will be compared.

  The molding die used for comparison was made of polypropylene (Novatech PP MG3F () so that the outer diameter edge and inner diameter edge fitting structure when fitting the male mold 2 and the female mold 1 are the combinations shown in Table 1. Novatec: registered trademark) manufactured by Nippon Polypro Co., Ltd.) and molded under molding conditions of a melting temperature of 200 degrees and a pressure of 100 MPa.

  The molding method of the annular lens 3 is as follows. In the molding dies of Examples 1 to 9, as a polymerizable monomer, 2-hydroxymethyl methacrylate 98% by weight, ethylene glycol dimethacrylate 2% by weight, azobis (2,4dimethylvaleronitrile) 0 After 2% by weight was mixed well and degassed, it was dispensed into female mold 1, and male mold 2 was fitted over it. Thereafter, the copolymer obtained by heating at 70 ° C. for 8 hours in a nitrogen atmosphere is released from the resin mold, and then swelled in a 37 ° C. phosphate buffer (PBS) for 60 minutes to obtain the target annular lens 3. It was. The fitting part shape and thickness of the obtained annular lens 3 were evaluated by the following methods.

[1. Shape of fitting part of outer diameter edge and inner diameter edge]
Evaluation of the fitting part shape confirmed the shape of the outer diameter edge and inner diameter edge of the annular lens 3 using an optical microscope at a magnification of 100 times. The ratio of the annular lens in which the occurrence of burrs was confirmed with respect to the total number of the obtained annular lenses was defined as the burring rate, and the fitting conditions of Examples 1 to 9 were calculated.

(Formula 1) Burr generation rate (%)
= (Number of annular lenses in which burr was confirmed / total number of obtained annular lenses) × 100
○: Occurrence rate less than 5% △: Occurrence rate less than 10% ×: Occurrence rate 10% or more

[2. Each area thickness]
Evaluation of thickness measured the thickness of the outer edge area | region 16, the inner edge area | region 14, and the intermediate | middle area | region 15 of the annular lens 3 using a thickness measuring device (G-1A, Ozaki Seisakusho Co., Ltd.), respectively, and then measured value. The average value of was calculated. Furthermore, the error with respect to the design value of the average value of the calculated thickness was made into the error rate, and it calculated about the fitting conditions of Examples 1-9.

(Formula 2) Error rate (%)
= (Average thickness value / design value) × 100
○: Design value less than ± 5% △: Design value less than ± 10% ×: Design value ± 10% or more

  In Examples 1 and 2, the burr generation rate of the fitting portion was low for both the outer diameter edge and the inner diameter edge, which was a favorable result. Further, the thickness of the intermediate region 15 is less than the target value ± 5%, and has the maximum thickness compared to the outer edge region 16 and the inner edge region 14, and shows a good result in controlling the thickness. Yes. In Examples 3 and 4, a gap is more likely to occur in the fitting portion than in Examples 1 and 2, so the rate of occurrence of burrs is slightly higher, and the accuracy is also slightly reduced in controlling the thickness. However, better results were obtained than when the line contact structure was used (Examples 5 to 9).

  In Examples 5 to 9, a line contact structure was used for one or both of the fitting portions. In Examples 5 to 9 using the line contact structure, since a gap is more likely to be generated in the fitting portion, the occurrence rate of burrs is higher than in Examples 1 to 4, and the thickness of the central portion is also implemented. As a result, the accuracy was lower than in Examples 1 to 4.

  From this comparison result, as shown in Examples 1 to 4, the mold for the annular medical device according to the present invention has a biting structure or / and an abutting structure at two fitting sites of the outer diameter edge and the inner diameter edge. More preferably, as shown in the first and second embodiments, a cut-off structure is used for one fitting site and a butting structure is used for the other fitting site.

  In addition, the shaping | molding die of the annular medical device which concerns on this invention does not exclude the structure which used the line contact structure for one or both of the fitting parts. In the molding die of the present invention in which two fitting parts are provided around, as a method for improving the accuracy of the fitting part of each of the outer diameter edge and the inner diameter edge, the two fittings are performed simultaneously. The method of forming a shaping | molding die is mentioned.

  The line contact structure is configured such that the fitting part of the female mold 1 and the male mold 2 makes the projection part of one mold abut the surface part of the other mold so that only the ridge line of the projection part contacts. For this reason, the adhesion at the time of fitting is weak, and an extremely sophisticated mold design and formation, and molding conditions for forming an extremely severe mold are required. On the other hand, in the cut-off structure or the abutting structure, since the molds are in contact with each other at the mating site (the mutual surface portions are in contact with each other at a substantially parallel or slight angle), It has become possible to easily give the same fitting accuracy as the method of forming the mold as is done.

DESCRIPTION OF SYMBOLS 1 Female type 2 Male type 4 Inner diameter edge fitting part 5 Outer diameter edge fitting part 6 Inner diameter edge fitting part 7 Outer diameter edge fitting part 8 Edge part 9 Bending part 10 Monomer reservoir

Claims (5)

A molding die formed by combining a female mold and a male mold and molding a medical device using a space generated between the female mold and the male mold,
The female part and the male part are fitted around two locations, the outer diameter edge and the inner diameter edge of the medical device,
In two fitting parts of the outer diameter edge and the inner diameter edge, one fitting part has a biting structure, and the other fitting part has a butting structure,
An annular medical device molding die for molding an annular medical device having an opening at a central portion of the medical device.   The annular medical device is formed in a lens shape having a curvature adapted to the curvature of the eye, the female die has a concave shape that provides a forming surface corresponding to the front curve surface of the annular medical device, and the male die is the The molding die for an annular medical device according to claim 1, wherein the molding die has a convex shape that provides a forming surface corresponding to a base curve surface of the annular medical device. 3. The molding tool for an annular medical device according to claim 1, wherein the annular medical device is formed such that a thickness of an intermediate region is larger than a thickness of an inner edge region and an outer edge region. In the annular medical device, the inner edge region has a thickness of 0.10 to 0.30 mm, the outer edge region has a thickness of 0.15 to 0.35 mm, and the intermediate region has a thickness of 0.20 to 0.40 mm. The mold for the annular medical device according to claim 3 , wherein the mold is formed as follows. An annular medical device having an opening in the center, the annular medical device being molded using the molding die according to any one of claims 1 to 4 .

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