JP2008191344A - Method for manufacturing marked contact lens and marked contact lens - Google Patents

Abstract

A method of manufacturing a contact lens with a mark using laser processing is provided. In particular, it is an object of the present invention to provide a novel method for manufacturing a contact lens, which can suppress protrusions formed around the laser beam during engraving and prevent adverse effects on wearing feeling and the like.
In any one of a mold 24, a resin mold 26, and a contact lens 10, a main laser processing for forming a mark 46 corresponding to a target mark 22 with a laser beam is performed, and an outer peripheral edge portion of the mark 46 is also provided. On the other hand, by performing auxiliary laser processing with a marking depth smaller than that of the main laser processing, the height of the protrusion 58 at the outer peripheral edge portion of the marking 46 accompanying the main laser processing is suppressed.
[Selection] Figure 1

Description

  The present invention relates to a manufacturing method of a contact lens with a mark formed by attaching a mark for identification to a contact lens and a contact lens with a mark.

  Conventionally, a label is attached to the lens surface for the purpose of identifying whether the contact lens is worn on the left or right, and displaying information such as the product number, lot number, front and back, and direction of the lens. Sometimes.

  As a method of marking on the lens surface, in general, a cutting process using a mechanical tool such as a milling cutter or a needle is directly applied to the lens surface for engraving or molding of a molding die used for molding a contact lens. It is known to transfer a mark engraved on a surface to a lens surface to give a mark. For example, Patent Literature 1 (Japanese Patent Laid-Open No. 2002-08320), Patent Literature 2 (Japanese Patent Laid-Open No. 2000-199875), Patent Literature 3 (Japanese Patent Laid-Open No. 07-186290), Patent Literature 4 (Japanese Patent Laid-Open No. 08-194193). This is what is shown in the Gazette.

  However, in cutting using a mechanical tool, the strength of the contact lens or the mold is not sufficiently secured due to stress concentration on the processing surface such as the lens surface or the molding surface, and the durability of the tool Due to the decrease, it may be difficult to place the same mark on a large number of lenses.

  Therefore, in recent years, as also shown in Patent Documents 1 to 4, as one of effective means for marking a processed surface, laser processing using laser light by high-density optical energy concentration The application of is being considered. According to such processing, the laser beam output member can be engraved without touching the processing surface by irradiating the processing surface with laser light to melt or evaporate the surface, and the strength is advantageous. Can be secured. In addition, the visibility of the mark is improved by light scattering by utilizing the fact that the bottom surface of the inscription is roughened by the laser beam being irradiated at a predetermined pitch width. It is also advantageously applied to formation.

  However, in the above-described laser processing, the outer peripheral edge of the engraving is raised due to the influence of heat due to light energy, and a bulge may protrude from the processed surface. Especially in the formation of minute marks, when the depth of engraving is increased to some extent in order to ensure the target visibility, it is often the case that the scanning speed of the laser beam is lowered or the pitch width is adjusted appropriately. As a result, there is a possibility that heat concentrates on the stamp and the bulge of the outer peripheral edge portion is further increased. In contact lenses, protrusions (including protrusions) appearing on the lens surface due to such bulges may cause a feeling of foreign matter and dirt during wearing. In other words, when the protrusion becomes large, the contact pressure on the eyelid, cornea, etc. increases, and the feeling of foreign matter increases, and there is a risk that dirt will easily accumulate at the recessed corners on both sides of the protrusion.

Japanese Patent Laid-Open No. 2002-082320 JP 2000-199875 A JP 07-186290 A Japanese Patent Laid-Open No. 08-194193

  Here, the present invention has been made in the background of the circumstances as described above, and the problem to be solved is the outer peripheral edge portion of the marking accompanying the laser processing while ensuring the depth dimension of the marking. It is possible to suppress the swell of the mark, so that both the visibility of the mark given by engraving and the feeling of wear can be advantageously achieved in a balanced manner, and a novel manufacturing method of a marked contact lens and a novel It is to provide a contact lens with a structure.

  Hereinafter, the aspect of this invention made | formed in order to solve such a subject is described. In addition, the component employ | adopted in each aspect as described below is employable by arbitrary combinations as much as possible. Further, aspects or technical features of the present invention are not limited to those described below, but are described in the entire specification and drawings, or an invention that can be understood by those skilled in the art from those descriptions. It should be understood that it is recognized based on thought.

  That is, the present invention is characterized in that at least one of the concave lens inner surface and the convex lens outer surface is molded using a resin mold molded by a mold, and at least one of the lens inner surface and the lens outer surface. A method of manufacturing a contact lens with a mark, wherein a main laser processing is performed by irradiating a laser beam to a position corresponding to a target mark in any of a mold, a resin mold, and a contact lens. In addition, the auxiliary laser processing is performed on the outer peripheral edge portion of the marking with a marking depth smaller than that of the main laser processing, thereby suppressing the height of the protrusions on the outer peripheral portion of the marking accompanying the main laser processing.

  According to such a manufacturing method according to the present invention, the height of the protrusion around the marking generated along with the main laser processing for marking can be suppressed by the auxiliary laser processing. Therefore, it is possible to secure the depth of the marking by main laser processing and realize good mark visibility, while suppressing the height of the protrusion around the mark, when wearing the contact lens caused by the protrusion This makes it possible to avoid problems such as foreign matter feeling and dirt.

  In the method of the present invention, a concave mark is formed on the inner surface or the outer surface of the contact lens by performing main laser processing and auxiliary laser processing on either a resin mold or a contact lens. I can do it. It should be noted that either one of the main laser processing and the auxiliary laser processing is applied to either one of the resin mold and the contact lens, and the other one of the resin mold and the contact lens, The other of main laser processing and auxiliary laser processing can be performed.

  On the other hand, in the method of the present invention, a convex mark can be formed on the inner surface or outer surface of the contact lens by subjecting the resin mold to main laser processing and auxiliary laser processing. Not only when the mark on the lens surface is formed in a concave shape, but also when it is formed in a convex shape, if there is a concave dent that has been transferred with projections due to the main laser processing around it, it will become soiled there. The problem is that it tends to accumulate, and the uneven area becomes larger by the amount of the concave depression, which may adversely affect the feeling of wearing, but such problems can be reduced by applying auxiliary laser processing according to the method of the present invention. Or can be eliminated.

  In the present invention, as the laser beam used for main laser processing and auxiliary laser processing, various laser beams suitable for processing of lenses, molds, resin molds, and the like can be used. For example, YAG laser or carbon dioxide gas In addition to a laser, an excimer laser, a semiconductor laser, and the like, a YAG fourth harmonic laser is preferably employed.

  In laser processing by the fourth harmonic (wavelength 266 nm) using YAG as a medium, since the laser is a deep ultraviolet laser having high workability, the target shape and size can be advantageously engraved. Furthermore, based on the fact that the rate of ablation processing is higher than thermal processing compared to other lasers, thermal effects on workpieces such as lenses, molds, and resin molds are reduced, resulting in thermal energy. An increase in the height of the protrusion around the marking is further advantageously suppressed. In the fourth harmonic laser processing, a laser using YV04 or YLF as a medium can be employed in addition to YAG.

  Moreover, in the manufacturing method of the contact lens with a mark which concerns on this invention, after giving a main laser process, you may give an auxiliary | assistant laser process. According to this method, after forming a mark associated with the main laser processing, auxiliary laser processing can be performed on the target protrusion as a target, which is caused by the main laser processing.

  Alternatively, in the method for manufacturing a marked contact lens according to the present invention, auxiliary laser processing may be performed before performing main laser processing. According to this method, it is possible to suppress the occurrence of protrusions around the marking at the time of marking accompanying the main laser processing. In addition, when performing the main laser processing, it is possible to use the trace of the auxiliary laser processing performed in advance as a guide. It should be noted that after the auxiliary laser processing is performed, the main laser processing is performed and the marking is performed, and further, the auxiliary laser processing may be performed as necessary.

  In the method of manufacturing a contact lens with marks according to the present invention, it is desirable that the width dimension by the auxiliary laser processing is smaller than the width dimension of the marking by the main laser processing. Thereby, it is possible to prevent the influence of the auxiliary laser processing from becoming excessively large as compared with the main laser processing and causing the occurrence of bulges and protrusions due to the auxiliary laser processing.

  In the method for manufacturing a contact lens with a mark according to the present invention, a laser beam used for main laser processing and a laser beam used for auxiliary laser processing are output, Qsw frequency, scanning speed, irradiation angle, and the number of scans. A method in which at least one of the wavelengths is different from each other is preferably employed. As a result, the depth and width are engraved to give sufficient visibility by the main laser processing, while the auxiliary laser processing has an adverse effect that is more than effective for suppressing the occurrence of projections that cause problems by the main laser processing. It is possible to control such as avoiding it. Also, the same type of laser light is adopted as the main laser light and auxiliary laser light, and the main laser is adjusted by varying at least one of the output, the Qsw frequency, the scanning speed, the irradiation angle, the number of scans, and the wavelength. Processing and auxiliary laser processing can be continuously performed in the same laser processing apparatus without removing the workpiece.

  Moreover, in the manufacturing method of the contact lens with a mark concerning this invention, it is desirable to employ | adopt a thing with a process spot diameter of 20 micrometers or less as a laser beam used for at least auxiliary laser processing. According to such a method, even if the problem protrusion is small, the laser light can be efficiently and accurately irradiated to the protrusion. In addition, since it is possible to suppress the laser light from being irradiated to the part other than the protrusions in the lens, the laser light forms a recess in an unintended part of the lens, or the processing is caused by the concentration of the thermal energy of the laser light. The formation of new protrusions on the outer peripheral edge of the part (irradiation part) is suppressed.

  Furthermore, the feature of the present invention relating to the marked contact lens is that at least one of the lens inner surface and the lens outer surface is directly engraved by irradiating a laser beam or molding the lens surface. It is a contact lens with a mark by transferring what is engraved by irradiating a laser beam on the molding surface of the mold used, and the outer peripheral edge of the mark is irradiated with laser light. The contact lens with a mark is formed with a linear processed surface extending along the edge of the mark with a depth smaller than that of the marking.

  In such a contact lens with a mark structured according to the present invention, the processing surface having a depth smaller than the marking is formed on the outer peripheral edge of the mark, thereby ensuring the visibility of the mark and the laser. The height of the protrusions on the outer peripheral edge of the mark due to light irradiation can be suppressed, and problems such as foreign matter feeling and dirt at the time of wearing the lens can be advantageously solved.

  The mold according to this structure includes a resin mold, a mold, and other molds that can be laser-processed on the surface and that are involved in the formation of the lens surface. The surface to be laser processed may be a lens surface (lens surface), or a resin mold or a resin mold for molding a lens as a mold used to mold the lens. It may be the surface of the mold. Since this is clear from the description of the present invention relating to the manufacturing method described above, redundant description is omitted.

  Further, in the present invention relating to the above contact lens, for example, the mark is formed in a concave shape on the lens surface, and a peripheral protrusion is formed on the concave outer peripheral edge due to laser light irradiation. A configuration in which a processing surface extending in a concave cross section with respect to the tip portion of the protrusion is formed can be suitably employed. By adopting such a configuration, it is possible to provide a contact lens that can more advantageously reduce irritation of marks on the eyelids and cornea during wearing.

  Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described. First, FIG. 1 shows a contact lens 10 as an embodiment of the present invention. The contact lens 10 has a thin, generally spherical shell shape as a whole, and is worn by being superimposed on the surface of the cornea of the eyeball. In addition, wearing means wearing and using for a human body.

  More specifically, the contact lens 10 according to the present embodiment can be applied to various contact lenses such as a soft contact lens, a hard contact lens, and a disposable contact lens. Further, the contact lens 10 is made of a resin material composed of various polymerizable monomers having optical characteristics such as light transmittance, and specifically, for example, hydroxyethyl methacrylate (HEMA) or polymethyl methacrylate (PMMA). , Cellulose acetate butyrate (CAB), silicone copolymer, fluorosilicone acrylate, fluorocarbon polymer, silicone rubber and the like.

  The contact lens 10 has a lens central axis as an optical axis, and has a rotationally symmetric shape around the central axis. The lens outer surface is constituted by a convex lens front surface, and the lens inner surface is constituted by a concave lens rear surface. In the center portion of the contact lens 10, a circular front optical part 12 and a rear optical part 14 are formed on the front and rear surfaces of the lens, respectively.

  The rear optical unit 14 is a concave having an appropriate curvature radius with a center of curvature set behind the lens on the lens center axis so as to be substantially similar to the surface of the cornea to be mounted under wearing conditions. A base curve surface having a vertical cross-sectional shape is formed. The vertical cross-sectional shape of the base curve surface takes into account the shape of the cornea, other wearing conditions or required optical characteristics, etc., for example, the curvature radius is constant or the curvature radius changes in the circumferential direction, etc. Various substantially spherical curved concave shapes are employed.

  On the other hand, the front optical unit 12 has a curved convex surface shape that provides optical characteristics such as a desired lens power in cooperation with the base curve surface set as described above.

  The front optical unit 12 and the rear optical unit 14 form an optical zone to which optical characteristics such as an appropriate lens power for correcting vision are given. The optical part is an area where an optical effect on the wearer's eyes is expected, and the boundary between the outer peripheral part, in other words, the peripheral part (described later) is generally on the lens front surface and the lens rear surface. Each can be considered as a point of change in curvature on the longitudinal section.For example, when the lens surface of the optical part is designed with a longitudinal section shape that gradually changes in the radial direction, or the boundary has a predetermined width in the radial direction. The boundary between the optical part and the peripheral part on the lens front and back surface is shaped as a line in the case where the optical part and the peripheral part are formed by a connection region that smoothly connects the optical part and the peripheral part between the front and rear surfaces of the lens. It does not necessarily have to be clear.

  A peripheral portion and an edge zone 16 are formed on the outer peripheral portion surrounding the optical portion of the contact lens 10. The end portion 16 has an annular shape at the outermost peripheral edge portion of the contact lens 10, and has a chamfered lens front and back surfaces extending inwardly from a substantially semicircular outer peripheral end surface in the longitudinal direction of the lens. I have. Further, the lens front and rear surfaces of the end portion 16 are connected to the front and rear surface peripheral portions 18 and 20.

  Each of the front peripheral portion 18 and the rear peripheral portion 20 has an annular shape continuously extending in the circumferential direction with a predetermined radial width dimension around the lens central axis. 14 and the end portion 16, the inner peripheral edge portions of the front and rear surface peripheral portions 18 and 20 are connected to the front and rear surface optical portions 12 and 14. That is, the front peripheral portion 18 and the rear peripheral portion 20 cooperate to form a peripheral portion that is positioned on the outer peripheral side of the optical portion of the lens 10.

  A mark 22 is attached to a predetermined portion of the front peripheral portion 18. The mark 22 is attached to identify the front and rear surfaces of the lens 10 and the position of the attached portion, whether the lens 10 is for the left eye or the right eye, etc. A size, a design, etc. are not specifically limited. For example, in the mark 22 according to the present embodiment, an appropriate character or mark is formed by a concave groove opened on the front surface of the lens 10.

  Next, a specific example of a method for manufacturing the contact lens 10 with the mark 22 as described above and a detailed shape of the mark 22 in the contact lens 10 manufactured thereby will be described.

  First, a female mold 24 and a male mold (not shown) are prepared as molds. These male and female molds are a lens mold female mold 26 and a lens mold male mold 28 (see FIGS. 3 and 4) as resin molds for obtaining the target contact lens 10 by molding (polymerization). ) Are independently produced by a known resin molding method. In particular, as the molding die, brihard steel suitable for laser processing as will be described later is preferably employed, but any other metal material can be employed. Further, as thermoplastic resin materials used for the lens mold female mold 26 and male mold 28, for example, polypropylene, polyethylene, polyethylene terephthalate, polystyrene, polycarbonate, vinyl chloride, nylon, polyacetal, fluororesin, etc. are all employed. Is possible.

  As shown in FIG. 2, the female mold 24 is composed of a first mold 32 having a concave spherical resin mold molding surface 30 in the central portion, and a convex spherical resin in the central portion. A second mold 36 having a molding surface 34 is included. In particular, the convex resin mold surface 34 of the second mold 36 has a shape corresponding to the front surface of the contact lens 10 having a substantially spherical convex shape.

  Then, the first and second molds 32 and 36 are closed in the axial direction by a mold clamping device (not shown), and a molding cavity 38 is formed between the mold mating surfaces of both the molds 32 and 36. The molding cavity 38 is injected and filled with a thermoplastic resin material through a sprue or runner 40 with an injection device (not shown), for example, and then cooled and solidified, and then a molded product made of the resin material is opened between the molds 32 and 36. Take out. Thereby, a female mold 26 for lens molding (see FIG. 3) is obtained. The concave spherical lens molding surface 42 of the lens molding female mold 26 is formed by the convex resin mold molding surface 34 of the second mold 36, thereby forming a shape corresponding to the lens front surface of the contact lens 10. ing.

  On the other hand, like the female mold 24, the male mold is composed of the first and second molds, and the lens mold male is between the mold-matching surfaces of both molds. A molding cavity corresponding to the mold 28 (see FIG. 4) is formed, and the male mold 28 for lens molding is molded with the male mold for molding by the same operation as that of the female mold 24. Is. Since the structure of the male mold is substantially the same as that of the female mold 24, the male mold is not shown here. Thus, the lens molding male mold 28 is obtained by the same resin molding method as the lens molding female mold 26 using the thermoplastic resin material and the male molding mold. The convex spherical lens molding surface 44 of the lens molding male mold 28 is formed by the convex resin mold molding surface 34 of the second mold 36, so that the shape corresponding to the lens rear surface of the contact lens 10 is obtained. Has been.

  In particular, in this embodiment, the marking 46 is formed by performing main laser processing on the resin mold molding surface 34 of the second mold 36 of the female mold 24 for the position corresponding to the mark 22 of the contact lens 10. Has been. That is, the resin mold molding surface 34 of the second mold 36 is irradiated with a laser beam to the portion corresponding to the mark formation position in the front peripheral portion 18 of the contact lens 10, so that the resin mold molding surface 34. By fusing the surface layer portion, a mark 46 having a shape corresponding to the target mark 22 is provided. For the purpose of reducing the thermal influence on the resin mold surface 34 of the second mold 36, such laser light is finely processed with good controllability and stability, and the fourth harmonic of the YAG laser. Waves are preferably used.

  Thereby, when the female mold 26 is resin-molded using the female mold 24, the marking 46 formed on the resin mold surface 34 of the female mold 24 is the female lens mold. It is transferred to the lens molding surface 42 of the mold 26. As a result, on the lens molding surface 42 of the female mold 26 for lens molding, a convex mark convex portion 48 corresponding to the mark 22 is formed at a portion corresponding to the formation position of the target mark 22 in the contact lens 10. Will be.

  Next, using the lens molding female mold 26 in which the mark convex portions 48 are formed in this way, and the lens molding male mold 28 obtained by resin molding using the male molding mold. Then, the target contact lens 10 is molded.

  For this purpose, first, as shown in FIG. 3, the lens-forming female die 26 is supported so as to open vertically upward, and a saucer-like region formed by the concave lens-forming surface 42 thereof. The polymerizable monomer 52 that is the material of the contact lens 10 is put through the injection tube 50. As the polymerizable monomer 52, various liquid monomer compositions used as raw materials for soft contact lenses, hard contact lenses and the like are appropriately employed. For example, in addition to a compound in which one or more of radically polymerizable compounds are blended, a compound composed of a macromer or a prepolymer may be used. Moreover, an appropriate crosslinking agent, a sensitizer, a thermal polymerization initiator, a photopolymerization initiator, and the like are blended with such a compound as necessary.

  Next, as shown in FIG. 4, the lens molding male mold 28 is overlapped in the axial direction (up and down in FIG. 4) from the vertical upper side of the lens molding female mold 26 to fit the mold. Then, a sealed molding cavity 54 is formed by being filled with the polymerizable monomer 52. Thereafter, the polymerization process of the polymerizable monomer 52 is performed while maintaining the mold matching state of both molds 26 and 28. As the polymerization treatment, photopolymerization or thermal polymerization is appropriately employed depending on the polymerizable monomer 52 to be employed.

  After the polymerization of the polymerizable monomer 52, the lens molding female mold 26 and the lens molding male mold 28 are opened, and the contact lens 10 made of the molded product subjected to the polymerization treatment is removed from the mold, whereby the intended contact is obtained. A lens 10 is obtained. For removing the contact lens 10, for example, the contact lens 10 attached to the lens molding surface 44 of the lens molding male mold 28 by mold opening is used, and the cylindrical portion of the lens molding male mold 28 is perpendicular to the axis. The lens molding surface 44 can be deformed by being crushed to be peeled from the lens molding surface 44, or by using an appropriate chemical.

  In the contact lens 10 thus polymerized and removed from the mold, the marking 46 formed on the resin mold surface 34 of the female mold 24 is formed on the lens molding surface 42 of the lens mold 26. Then, it is transferred to the front surface of the contact lens 10 to form a concave mark 22 having a shape corresponding to the marking 46 at the target position in the periphery of the contact lens 10. .

  By the way, when the above-described main laser processing is performed on the female mold 24 to form the marking 46, the visibility of the mark 22 transferred to the contact lens 10 is ensured, and there is particularly some wear. In order to ensure good visibility, it is required to set the depth dimension d1 of the marking 46 to be large to some extent. The depth dimension d1 of the marking 46 is appropriately set to such an extent that visibility can be ensured in consideration of the optical characteristics, thickness dimension, material, and width dimension of the marking 46, etc. Although not particularly limited, it is generally desirable that d1 = 1 to 50 μm. This is because if it is smaller than 1 μm, the visibility is difficult to be secured, whereas if it is larger than 50 μm, the strength of the lens 10 may be lowered.

  Further, the female mold 24 is subjected to auxiliary laser processing in addition to the main laser processing at the portion where the marking 46 is formed. In this auxiliary laser processing, after the main laser processing is performed on the female mold 24 or before the main laser processing is performed, a laser beam is applied to the outer peripheral edge portion of the mark 46 accompanying the main laser processing. Is done by.

  In the auxiliary laser processing, preferably, a laser beam having a processing spot diameter of 20 μm or less is applied to the outer peripheral edge of the mark formed by the main laser processing over the entire periphery of the opening peripheral edge of the concave mark 46. It is performed by irradiating at a predetermined interval (pitch). The laser beam used for the auxiliary laser processing is preferably a YAG fourth harmonic laser as in the case of the main laser processing, but at least one of the output, the Qsw frequency, the scanning speed, the irradiation angle, the number of scans, and the wavelength. The tuning is different from that of the main laser beam.

  Thereby, the concave part by auxiliary laser processing is formed with a smaller depth and width than the main laser processing. Thus, as shown in FIG. 6, a concave portion formed by auxiliary laser processing is formed at a position corresponding to the protrusion 58 expressed on the outer peripheral edge portion of the mark 46 by main laser processing. As a result, the height dimension h2 can be suppressed and the overall volume of the projection 58 formed over the entire periphery of the opening peripheral portion of the mark 46 by the main laser processing can be suppressed by the auxiliary laser processing. I can do it.

  More specifically, when the auxiliary laser processing is performed after the main laser processing is performed first, the stamp 46 is first formed by the main laser processing, which is caused by melting or the like of the formation portion of the stamp 46. As shown in FIG. 5, a protrusion 58 as a peripheral protrusion that protrudes from the reference surface (molding surface 34) toward the opening direction of the mark 46, as shown in FIG. Occur. Therefore, by applying auxiliary laser processing toward the position of the center of the protrusion 58 in the width direction, the tip portion of the protrusion 58 is melted or evaporated. By this auxiliary laser processing, as shown in FIG. 6, a recess 60 having a depth: d2 is formed with respect to the tip portion of the protrusion 58, and the protrusion height: h2 of the protrusion 58 is the initial height: It is made smaller than h1. Further, if necessary, the depth and width of the recess 60 with respect to the protrusion 58 are increased to an appropriate size as shown in FIG. 7 by continuing the auxiliary laser processing on the protrusion 58 continuously or intermittently. It can be made. As a result, a recess 62 having a depth: d3 larger than the recess 60 having a depth: d2 is formed, and the height of the protrusion 58 can be further reduced.

  In addition, since auxiliary | assistant laser processing processes the metal mold | die 24 for a female mold which is the target object of the same material as main laser processing, it is desirable to employ | adopt the same laser beam as a main laser and an auxiliary | assistant laser. However, as described above, the auxiliary laser processing is intended to reduce the protrusion 58 generated around the marking 46 when the marking 46 is formed by the main laser processing. By adjusting and changing at least one of the frequency, the scanning speed, the irradiation angle, the number of scans, and the wavelength, the concave portion 62 having a depth smaller than the depth of the marking 46 by the main laser processing is formed.

  For the purpose of the auxiliary laser processing as described above, in general, the height of the projection 58 is h1 and the concave portions 60 and 62 formed by the auxiliary laser processing as compared with the depth d1 of the marking 46 formed by the main laser processing. The depths d2 and d3 are reduced. Also, the width dimensions: w2, w3 of the recesses 60, 62 formed by the auxiliary laser processing are made smaller than the width dimension: w1 of the inscription 46 formed by the main laser processing. As is clear from the above description, in the present embodiment, the processing surface formed by laser processing at a depth: d3 smaller than the marking 46 by laser beam irradiation is a concave portion at the outer peripheral edge portion of the mark 22. 60 and the recessed part 62 are comprised.

  The auxiliary laser processing may be formed in a line at the tip portion (top) of the protrusion 58, or the tip portion of the protrusion 58 is irradiated with pulsed laser light in a staggered manner or a plurality of rows. It is also possible. Further, the auxiliary laser processing need not be formed over the entire circumference of the peripheral edge of the opening of the marking 46. For example, the auxiliary laser processing may be performed only on a portion where the protrusion 58 has a large protruding height on the periphery. good.

  5 to 7 show a schematic shape of the female mold 24 (second mold 36), and the bottom surface of the engraved mark 46 is substantially flat. In order to form the mark 46 of the desired width dimension: w1 and depth dimension: d1, pulsed laser light is irradiated at a predetermined interval. As a result, as shown in FIGS. 8 and 9, the bottom surface of the marking 46 is formed into an uneven shape. The uneven shape of the mark 46 is transferred to the contact lens 10 via the lens molding female die 26, and the concave bottom surface of the mark 22 is made rough, thereby improving the visibility of the mark 22. Will also contribute.

  Furthermore, the processed surface 62 formed at the tip portion of the protrusion 58 by the auxiliary laser processing is generally formed by using pulsed laser light in the same manner as the main laser processing. In addition, the depth and the width dimension are smaller in the portion processed by the auxiliary laser processing than the portion processed by the main laser processing, and therefore, the unevenness (rough surface state) on the processed surface 62 is omitted in FIG.

  In the contact lens 10 having the above-described structure, the height of the protrusion 58 accompanying the formation of the mark 46 by the main laser processing in the female mold 24 is the height of the processing surface (concave portion 62) by the auxiliary laser processing. By being restrained by the formation, the height of the projection 58 projected from the outer peripheral edge portion of the mark stamp 56 of the contact lens 10 based on the transfer of the stamp 46 can be suppressed. As a result, problems such as foreign object feeling and dirt caused by wearing the contact lens 10 due to the height of the protrusion can be advantageously solved.

  In other words, the height of the protrusion 58 accompanying the main laser processing is lowered to a desired dimension level by the auxiliary laser processing, so that the marking 46 by the main laser processing can be obtained in a desired manner without special consideration for the height of the protrusion 58. It becomes possible to process the depth dimension: d1. Therefore, the depth dimension of the mark stamp 56 transferred by the stamp 46 of the mold 24 can be set to a desired value, and the visibility of the mark 22 can be suitably secured.

  Moreover, the tip shape of the protrusion 58 formed around the marking 46 is roughened by the auxiliary laser processing, and the tip shape of the outer peripheral edge of the mark 22 of the contact lens 10 formed by the transfer is also roughened. Therefore, the visibility of the outline of the mark 22 can be further improved.

  Further, when the recess 62 serving as the processing surface is formed by auxiliary laser processing, a laser beam having a processing spot diameter of, for example, 20 μm or less is employed, which advantageously affects the thermal effect on the female mold 24. It can be suppressed. Therefore, the influence on the processed surface by the auxiliary laser processing does not become a big problem.

  Furthermore, in the present embodiment, the main laser processing is performed on the female mold 24 to form the stamp 46, and the auxiliary laser is applied to the protrusion 58 formed on the outer peripheral edge portion of the stamp 46 of the mold 24. By performing the processing, the height of the projection 58 in question is suppressed before the stamp 46 is transferred to the lens surface. Therefore, even when a large number of contact lenses 10 with marks 22 are manufactured, it is possible to save the labor of performing main laser processing and auxiliary laser processing on each contact lens 10 and to improve the productivity of the contact lens 10. Can be improved.

  However, depending on the restrictions and conditions of the manufacturing process, manufacturing equipment, etc., the outer peripheral portion of the mark is affected by the thermal energy of the laser beam after the main laser processing is performed directly on the contact lens 10 and the mark representing the mark is applied. Auxiliary laser processing may be applied to the protrusions formed on the substrate. Alternatively, the main laser processing is performed on the female mold 24 to form the marking 46, and the marking 46 having the projection 58 on the outer peripheral edge is transferred to the lens surface, and the projection formed on the contact lens 10 is applied. It is also possible to perform auxiliary laser processing. Further, as in the above-described embodiment, the main laser processing and the auxiliary laser processing are performed on the female mold 24, and the stamp 46 with the protrusion height of the outer peripheral edge portion suppressed is attached. After the mark 22 (mark mark 56) is transferred to the projection, the auxiliary laser processing is further applied to the protrusion whose protrusion height is suppressed at the outer peripheral edge portion of the mark 22 to further reduce the protrusion height. May be.

  Alternatively, the lens forming surface 42 of the lens forming female mold 26 shown in FIG. 3 is subjected to main laser processing to form a mark, and an auxiliary laser is applied to the protrusion formed around the mark. Processing may be performed to suppress the height of the protrusions. According to such laser processing, for the convex mark formed by transferring the stamp of the female mold 24 to the lens molding surface 42 of the female mold 26 in the above embodiment. On the contrary, a concave stamp is formed instead of the convex portion 48. Then, as shown in FIG. 4, by using this lens molding female mold 26, a target contact lens is formed by superposition, so that a convex mark corresponding to the marking is formed on the front surface of the contact lens. Can be formed.

  As described above, even when a convex mark is formed on the surface of the contact lens, the present invention can be advantageously applied, and thereby, the peripheral edge of the convex mark extends in a peripheral shape. It becomes possible to suppress the contour-like projections to be small, and thereby, the same effects as those of the above-described embodiment such as improvement of wearing feeling and reduction of dirt can be obtained. The formation of the convex mark in such a contact lens can be fully understood from the description of the above embodiment with reference to FIGS. 3 and 4, and can be easily performed by those skilled in the art. Here, illustration is omitted.

  The embodiment of the present invention has been described in detail above, but this is merely an example, and the present invention is not limited to a specific description in the embodiment, and is based on the knowledge of those skilled in the art. The present invention can be implemented with various changes, modifications, improvements, and the like, and any such embodiments are included in the scope of the present invention without departing from the spirit of the present invention. Needless to say.

  For example, the shape and size, number, and position of the stamp 46 representing the mark 22, the protrusion 58 on the outer peripheral edge of the mark 46, the recesses 60 to 62 attached to the protrusion 58, and the like are provided. Alternatively, the difference between the front surface and the rear surface of the resin mold for lens molding or the contact lens 10 is not limited at all, and is not limited to that illustrated.

  Specifically, in the method of manufacturing the contact lens 10 according to the above embodiment, after marking the resin mold surface 34 of the female mold 24 by main laser processing, the outer peripheral edge of the stamp 46 is marked. Auxiliary laser processing was performed on the generated protrusion 58, but as described below with reference to FIGS. 10 to 12, on the contrary, auxiliary laser processing may be performed first. Is possible. 10 to 12, members and portions having substantially the same structure as those of the above-described embodiment are denoted by the same reference numerals as those of the above-described embodiment, and detailed description thereof is omitted. .

  That is, as shown in FIG. 10, first, auxiliary laser processing is performed by irradiating a laser beam to a position corresponding to the outer peripheral edge portion of the marking 46 on the resin mold surface 34 of the female mold 24. By applying, the recessed part 64 is formed. In this specific example, in order to attach the linear marking 46 similar to that of the above embodiment, the concave portions 64 are formed at positions corresponding to the upper end portions of the both wall portions in the width direction and the upper end portions of both end portions in the longitudinal direction. To do. In addition, as the mold 24 is melted by the laser beam to form the concave portion 64 having a predetermined depth dimension: d4, the protrusion height: h3 is small on the outer peripheral edge portion and the inner peripheral edge portion of the concave portion 64, respectively. Although the protrusions 66 are formed, since the energy exerted by the auxiliary laser processing is sufficiently smaller than the energy by the main laser processing, these small protrusions 66 do not become a big problem.

  Next, a laser beam is applied to the inner side of the resin mold molding surface 34 surrounded by the recesses 64 to perform main laser processing, thereby providing a mark 46. In particular, as shown in FIG. 11, by appropriately adjusting the depth dimension d5 and the width dimension of the marking 46, the small protrusion 66 on the inner peripheral edge of the recess 64 is formed along with the formation of the marking 46. It can also be lost by melting or evaporation.

  In addition, as shown in FIG. 12, even when a laser beam by main laser processing is continuously irradiated to a predetermined portion of the mark 46 and a mark 46 having a larger depth dimension: d1 is attached, The process which consists of the recessed part 64 whose height dimension: h4 of the processus | protrusion 68 formed in the outer-periphery edge part of the marking 46 under the influence of the heat by laser processing is smaller than the marking 46 previously formed there. The height of the protrusion 68 is suppressed by the surface.

  Further, the markings and marks can be formed on the rear surface of the contact lens or its molding surface instead of or in addition to the front surface of the contact lens or its molding surface.

  Tests conducted to confirm the technical effects of the contact lens manufacturing method according to the present invention are described below as examples.

  A sample 70 made of the same material as the female mold 24 (second mold 36) used for manufacturing the contact lens 10 according to the embodiment is prepared. The material of the sample 70 is STAVAX (trademark) plated with nickel.

  By irradiating the surface of the sample 70 with laser light and performing main laser processing, a substantially straight groove-shaped mark is given. In the main laser processing, a YAG fourth harmonic laser was used as the laser beam, the Qsw frequency was 2.5 KHz, the output was 150 mW, the moving speed (scanning speed) was 10 mm / s, and the spot diameter was about 20 μm. Since the dot interval of the laser beam is obtained by dividing the scanning speed by the Qsw frequency, the dot interval is controlled by changing the setting of the scanning speed while the Qsw frequency is constant. Thereby, from the relationship between the dot interval and the spot diameter of the laser beam, for example, by applying laser processing so as to overlap the irradiated region of the laser beam by narrowing the dot interval, to increase the depth of the processing site, Depth adjustment is suitably performed, for example, by widening the dot interval of the laser light irradiation region to reduce the depth of the processing region as a whole. In this embodiment, since the spot diameter of the laser beam is about 20 μm, the Qsw frequency is 2.5 kHz, and the scanning speed is 10 mm / s, the dot interval is about 4 μm, and 75 laser beam irradiation sites are adjacent to each other. % Laser processing is applied. FIG. 13 shows an enlarged longitudinal section of the marked portion of the sample 70 obtained as a result, as Comparative Example 1.

  Further, the surface of the sample 70 is irradiated with a laser beam and subjected to main laser processing so that a substantially straight groove-shaped inscription is applied to the periphery (outer peripheral edge) of the inscription in the sample 70 with the inscription. Then, auxiliary laser processing was performed by irradiating laser light. In the auxiliary laser processing, the same YAG 4th harmonic laser as the main laser processing is adopted as the laser beam, and the dot interval is controlled to about 8 μm by changing only the scanning speed to 20 mm / s, and lasers adjacent to each other The light irradiation sites were overlapped by about 40%. As a result, the auxiliary laser processing is adjusted to reduce the depth of the processed portion as a whole by reducing the overlap of the irradiated portions compared to the main laser processing. FIG. 14 shows an enlarged vertical cross section of the sample 70 where the main laser processing and the auxiliary laser processing were performed, as a result, as Example 1.

  From the results shown in FIGS. 13 and 14, in Example 1 where the auxiliary laser processing was performed, the formation of the sharply shaped protrusions on the sample 70 was compared with Comparative Example 1 where the auxiliary laser processing was not performed. It is recognized that the state of the longitudinal section is made gentle throughout.

  Further, under the same laser light conditions as in Example 1, the surface of the sample 70 was subjected to main laser processing to give a linear marking, and the outer peripheral edge of this marking was subjected to auxiliary laser processing. . Then, the height dimension of the peripheral part on the left side (L) in the width direction of the inscription and the height dimension of the peripheral part on the right side (R) in the width direction were measured. The results are shown in Table 1 as Example 2. Further, under the same laser light irradiation conditions as in Comparative Example 1, the surface of the sample 70 was subjected to main laser processing to give a linear marking, and then the height dimension of the peripheral portion on the left side (L) in the width direction of the marking And the height dimension of the peripheral part on the right side (R) in the width direction was measured. The results are also shown in Table 1 as Comparative Example 2.

  From Table 1, it is clear that in Example 2 where the auxiliary laser processing was performed, the height of the peripheral portion of the engraving was lower than in Comparative Example 2 where the auxiliary laser processing was not performed.

  Based on the results of Examples 1 and 2, according to the contact lens manufacturing method of the present invention, it is presumed that the height of the protrusions accompanying the main laser processing can be advantageously suppressed by performing the auxiliary laser processing. .

  Next, based on the manufacturing method of the contact lens with a mark according to the present invention, a longitudinal rectangular shape having a width dimension of about 200 μm, which is necessary for manufacturing a lens having the desired visibility and wearing feeling, is obtained. An example of a procedure for forming the mark 72 is shown (see FIG. 19).

  First, as shown in FIG. 15, the main laser processing is applied to the center of the formation site of the target mark 72, and the first extending linearly in the longitudinal direction of the mark 72 (up and down in FIG. 15). A main stamp 74 is formed. In particular, in the first main engraving 74, the main laser processing is performed from one end to the other end, and from the other end to the one end, The main laser processing is performed twice so as to reciprocate the formation site between the other ends.

  Next, as shown in FIG. 16, the second main stamper in the shape of a rectangular frame is separated by a pitch of 5 μm to 10 μm outward in the width direction and in the longitudinal direction of the first main stamp 74. 76 is formed by main laser processing. In the second main stamp 76, the main laser processing is performed twice (twice) on the rectangular frame-shaped formation site.

  Further, as shown in FIG. 17, the second main stamp 76 has a width similar to that between the first main stamp 74 and the second main stamp 76 outward in the width direction and in the longitudinal direction. A third main stamp 78 having a rectangular frame shape is formed by main laser processing at a pitch. In the third main marking 78, the main laser processing is performed once (once) on the rectangular frame-shaped formation site.

  Further, as shown in FIG. 18, the fourth main mark 80 having a rectangular frame shape is separated from the main laser by separating the pitch from the third main mark 78 in the width direction and the longitudinal direction. Formed by processing. In the fourth main stamp 80, the main laser processing is performed once (one time) on the formation part of the rectangular frame shape. Further, in the same manner as the formation of the fourth main stamp 80 on the outer peripheral side of the fourth main stamp 80, the fifth to twelfth main stamps 82, 84, 86, 88, 90 whose outer dimensions are gradually increased. , 92, 94, 96 are formed by main laser processing, and the mark 72 forms an outer shape of a substantially desired size.

  After forming the marks 72 constituting the substantially desired size of the outer shape, the main laser processing from the first main stamp 74 to the twelfth main stamp 96 is repeated a desired number of times. As a result, the depth dimension of the mark 72 is formed to a target dimension.

  Furthermore, as shown in FIG. 19, it assists a protrusion (not shown) formed so as to rise on the outer peripheral edge of the twelfth main stamp 96 due to the thermal energy of the main laser processing. Apply laser processing. As a result, a first auxiliary stamp 98 having a rectangular frame shape is formed on the outer peripheral side of the twelfth main stamp 96, and the height of the protrusion on the outer peripheral edge of the twelfth main stamp 96 is reduced. In particular, in the first auxiliary marking 98, the auxiliary laser processing is performed twice (twice) on the protrusion of the outer peripheral edge portion of the twelfth main marking 96 which is a rectangular frame-shaped forming portion.

  Further, the outer peripheral edge portion of the first auxiliary stamp 98 was formed so as to rise due to the heat energy generated by subjecting the protrusion at the edge of the twelfth main stamp 96 to the auxiliary laser processing twice. Auxiliary laser processing is performed once on the protrusion. As a result, a rectangular frame-shaped second auxiliary marking 100 formed by one auxiliary laser processing is formed on the outer peripheral side of the first auxiliary marking 98, and the height of the protrusion on the outer peripheral edge of the first auxiliary marking 98 is increased. Reduce the thickness.

  In the mark 72 according to the present embodiment, in addition to sufficiently obtaining the target visibility, no protrusion having a size that may adversely affect the wearing of the lens is found on the outer peripheral edge of the mark 72. Was recognized. Also from this, it is considered that by providing the second auxiliary stamp 100 in addition to the first auxiliary stamp 98, the height of the above-mentioned problem projection can be effectively suppressed, and an excellent wearing feeling can be obtained. It is done.

  In particular, in this embodiment, the operation of applying the same main laser processing and auxiliary laser processing to the portion where the first main stamp 74 or the second auxiliary stamp 100 is formed again is repeated a desired number of times, and the following operation is performed. It turns out that an effect is acquired. That is, since the laser irradiation energy per scan can be made relatively small, the thermal influence on the processed portion can be made small. Further, if the time until the second scanning is made longer than the thermal relaxation time of the machining site, the thermal influence on the machining site can be further reduced. Furthermore, since the processing depth per scan becomes shallow, the processing depth can be highly controlled by the number of scans. Furthermore, since the unevenness of the processed surface can be made finer due to the low energy per pulse, it is possible to form marks with good visibility by controlling, for example, the degree of light scattering It becomes.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective explanatory view showing a part of a contact lens as an embodiment of the present invention. The longitudinal cross-section explanatory drawing which shows the metal mold | die for female type | molds used for manufacture of the contact lens. The longitudinal cross-sectional explanatory drawing which shows one manufacturing process of the contact lens. The longitudinal cross-sectional explanatory drawing which shows another manufacturing process of the contact lens. The longitudinal cross-sectional explanatory drawing which expands and shows the principal part of one manufacturing process of the 2nd metal mold | die which comprises some female molds for the same type. The longitudinal cross-sectional explanatory drawing which expands and shows the principal part of another one manufacturing process of the 2nd metal mold | die. The longitudinal cross-sectional explanatory drawing which expands and shows the principal part of another one manufacturing process of the 2nd metal mold | die. FIG. 6 is an enlarged explanatory view in which a main part in FIG. 5 is cut out. FIG. 8 is an enlarged explanatory view in which a main part in FIG. 7 is cut out. The longitudinal cross-sectional explanatory drawing which expands and shows the principal part of one manufacturing process of the metal mold | die for metal mold | die used for manufacture of the contact lens as another one Embodiment of this invention. The longitudinal cross-section explanatory drawing which expands and shows the principal part of another one manufacturing process of the same metal mold | die. The longitudinal cross-sectional explanatory drawing which expands and shows the principal part of another another manufacturing process of the same metal mold | die. The measurement figure which shows the longitudinal cross-sectional shape measurement result of the contact lens as the comparative example 1 which concerns on the Example of this invention. The measurement figure which shows the longitudinal cross-sectional shape measurement result of the contact lens as Example 1 which concerns on the Example. Plane explanatory drawing which shows typically one process of forming a mark according to a manufacturing method of a contact lens with a mark in the example. Plane | planar explanatory drawing which shows another 1 process of forming the mark like a model. Plane explanatory drawing which shows another another process of forming the mark as a model. Plane explanatory drawing which shows further another process of forming the mark as a model. Plane explanatory drawing which shows another one process which forms the mark suitably for a model.

Explanation of symbols

10: contact lens, 12: front optical part, 18: front peripheral part, 22: mark, 24: female mold for molding, 26: female mold for molding, 46: stamp, 58: protrusion

Claims (8)

A marked contact lens in which at least one of a concave lens inner surface and a convex lens outer surface is molded using a resin mold molded by a mold, and at least one of the lens inner surface and the lens outer surface is marked A manufacturing method of
In any one of the mold, the resin mold, and the contact lens, a main laser processing is performed by irradiating a laser beam at a position corresponding to the target mark, and the outer peripheral portion of the mark is applied. A method of manufacturing a contact lens with a mark, characterized in that the height of a protrusion at an outer peripheral edge portion of the engraving accompanying the main laser processing is suppressed by performing auxiliary laser processing at a marking depth smaller than the main laser processing .   The manufacturing method of the contact lens with a mark of Claim 1 which performs the said auxiliary | assistant laser processing after giving the said main laser processing.   The manufacturing method of the contact lens with a mark of Claim 1 which performs the said auxiliary | assistant laser processing before performing the said main laser processing.   The manufacturing method of the contact lens with a mark as described in any one of Claims 1 thru | or 3 with a small width dimension by the said auxiliary | assistant laser processing compared with the width dimension of the marking by the said main laser processing.   The laser light used for the main laser processing and the laser light used for the auxiliary laser processing are different from each other in at least one of output, Qsw frequency, scanning speed, irradiation angle, scanning frequency, and wavelength. The manufacturing method of the contact lens with a mark as described in any one of 4.   6. The method for producing a marked contact lens according to any one of claims 1 to 5, wherein at least a laser beam having a machining spot diameter of 20 [mu] m or less is used as the laser beam used for the auxiliary laser machining. At least one of the lens inner surface and the lens outer surface is directly engraved by irradiating a laser beam, or by irradiating a laser beam onto a molding surface used for molding the lens surface. A contact lens with a mark that is marked by being transferred,
A contact lens with a mark, wherein a linear processed surface extending along an edge of the mark is formed at an outer peripheral edge portion of the mark with a depth smaller than the inscription by the laser light irradiation. .   The mark is formed in a concave shape on the lens surface, and a peripheral protrusion due to the irradiation of the laser light is formed on the outer peripheral edge of the concave shape, and a concave cross section with respect to a tip portion of the peripheral protrusion The marked contact lens according to claim 7, wherein the processed surface extending at a point is formed.

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